HELSINGIN YLIOPISTON MAANTIETEEN LAITOKSEN TUTKIMUSRETKIRAPORTTEJA 50 ISSN

Transkriptio

1 HELSINGIN YLIOPISTON MAANTIETEEN LAITOKSEN TUTKIMUSRETKIRAPORTTEJA 50 LANDSCAPES AND LICHENS OF TAITA HILLS, KENYA Edited by Tuuli Toivonen Jouko Rikkinen Petri Pellikka 2012 ISSN EXPEDITION REPORTS OF THE DEPARTMENT OF GEOGRAPHY, UNIVERSITY OF HELSINKI 49

2 Foreword Foreword Biologists and geographers of the University of Helsinki have been carrying out field work in East Africa for several decades. Geographers organized the first student field excursion to Kenya in 1989 and visited also Taita Hills. The field excursion of January 2011 was the first to take advantage of the newly opened Taita Research Station research station of the University of Helsinki. The station was officially opened by the University rector and a large number of representatives from different scientific and administrative bodies just on the preceding week of the excursion (Fig. 1). The research station is the only overseas research station owned by the University of Helsinki and has been established to serve scientists from various fields of science. Already now, international research groups study biodiversity patterns and interactions, land use practices and land cover change, climate change implications and water resources in the region. At the University of Helsinki, at least 26 Master s theses and 7 doctoral dissertations of have dealt with issues of Taita Hills. Figure 1. H.E. Ambassador Heli Sirve and rector Thomas Wilhelmsson cutting the ribbon of the Taita Research Station. Prof. Petri Pellikka on the right. The Taita Hills area in the Taita-Taveta district is intriguing for research for several reasons. The area is characterised by distinct topographical variation: the mountainous Taita Hills at m.a.s.l raise from the Tsavo Plains. The ancient Precambrian hills belong to the Eastern Arc mountain chain (Figure 2) and they are classified as one of the world s 34 most important biodiversity hotspots. Indigenous mountain rain forest fragments on the hills accommodate a variety of endemic and threatened flora and fauna not recognizable elsewhere in Africa. Of the whole Taita-Taveta district 62% of the area is national park, thus protected. The main basis of the living in the highlands is intensive agriculture, which is the main source of livelihood for 78% of people in the district. The population has doubled within 30 years and the highest growth rates are reported among the younger age groups. The pressure on land also results in increased human-wildlife conflicts as well as land use disputes between farmers and managers of sisal plantations and national parks. The seven-day field excursion of January 2011 to the region was a joint venture of botanists, particularly lichen researchers, and geographers of the University of Helsinki. The results of the field trip are presented in the following chapters. 1

3 Foreword First, there are two chapters describing the research environment of the Taita Hills area: the impact of the newly opened research station (chapter I) and the description of the field plots of international researchers (chapter II). The vegetation characteristics of the forests, woodlands and agroforestry are presented in chapters III and IV, while chapters V-VIII provide insights on the lichens of the Taita Hills. Lichens of the area are presented in Finnish also in the pages of Stack (Pinkka) of the University of Helsinki: University of Helsinki participates in a number of research projects in East African Mountains and Taita Hills specifically. Information about the current research activities can be found e.g. from the pages of the respective research groups and the Taita Research Station ( Figure 2. Location of Taita Hills in the Eastern Arc Mountains (presented in black). The Taita Hills (03 25 S and E). Map by H. Riihimäki. In Helsinki, Petri Pellikka, Jouko Rikkinen & Tuuli Toivonen 2

4 Contents Contents Foreword... 1 Contents... 3 I. Locals and the new Station: Local knowledge about the new Research Station Terra at Wundanyi, Taita Abstract... 5 Taita Research station... 5 Method and the data... 6 Results... 7 Conclusions and lessons learnt... 9 II. Ongoing scientific work on forest ecosystems in Taita Hills area a brief description Abstract Introduction FHM and FIA-proctocol plots Belgian and Finnish plots Conclusions References III. On the vegetation composition and structure of the forests, woodlands and agroforestry areas of Taita Hills, SE Kenya Abstract Introduction Study Area Materials and methods Indigenous forests Exotic forests Woodlands Agroforestry areas Conclusions References IV. The misty Cloud forest of Taita hills Abstract Introduction What are cloud forests? Inside the cloud forest Importance of epiphytic plants Fieldwork and preliminary results from the Taita Hills References V. Some insights to the lichens of the Taita Hills Abstract Introduction Lichens on the rocks of Ngangao Acknowledgements Literature: VI. Lichen herbivory Abstract Introduction References VII. The lichen genus Coccocarpia in Taita Hills, Kenya Abstract

5 Contents Introduction Morphology and anatomy Preliminary observations from Taita Hills and Mt. Kasigau References VIII. Cyanobionts of some Lobaria, Pseudocyphellaria and Sticta species in Taita Hills, Kenya Introduction to cyanolichens Materials and Methods Cyanobionts of some Lobaria, Pseudocyphellaria and Sticta species in Taita Hills, Kenya Acknowledgements References IX. Newtonia buchananii and wood-rotting Phellinus species in the Taita Hills Introduction References TRAVEL DIARIES OF THE EXCURSION - MATKAPÄIVÄKIRJAT Excursion ensimmäinen päivä, Nairobi Sunnuntai Nairobista tutkimusasemalle Wundanyissa - Maanantai Ngagaon metsässä - Tiistai Vurialla - Keskiviikko Tsavon retki Perjantai Viimeinen päivä Taitalla Lauantai

6 I. Locals and the new Station: Local knowledge about the new Research Station Terra at Wundanyi, Taita. I. Locals and the new Station: Local knowledge about the new Research Station Terra at Wundanyi, Taita. Reeta Airaksinen Abstract This paper reports the local knowledge and attitudes towards Taita Research station at Wundanyi, Kenya. University of Helsinki established a new research station at Taita Hills in January One of the station s aims is community outreach and there was a need to canvas local knowledge of and attitudes towards the newly opened station. There were 22 locals interviewed in one day at the village of Wundanyi. This paper summons up a broad picture of the impressions and opinions that the Taita people have about Taita Research station and the type of functions it represents. Interviews served also as a promoting opportunity because there were leaflets distributed at the same time. Taita Research station The University of Helsinki (Fig. 1) established research station in Wundanyi, Kenya. It is located in south-eastern part of the country, in the Taita Hills. The forests as well as the agricultural land suffer from degradation due to population pressure, thus the complexity of natural resource management and the remnants of biodiversity have attracted and provided challenges for researchers in various disciplines. Taita Hills caters especially well for biosciences, studies in climate land cover feedback mechanisms, agricultural sciences, studies in rural development and environmental conservation etc. Research station was earlier a missionary house called Hebron. It was built in the 1980 s by the Scripture Mission. Beside mission work and place for Christian forum it served also as a guesthouse (Taita Environmental Research and Resource Arc 2011). Figure 1. Taita Research Station (left) was established in January 2011(photo by R. Airaksinen). The building was originally built as missionary station in the 1980s by Norwegian missionary Jon Jøssang (right, photo published with the authorisation from Jon Jøssang). 5

7 I. Locals and the new Station: Local knowledge about the new Research Station Terra at Wundanyi, Taita. Taita Research station Terra was opened in January The opening ceremony was held on the 12 th of January. The whole-day ceremony was honoured by dignified guests, such as the Ambassador of Finland, Rector of the University of Helsinki, Deputy Director of Kenya Forestry Service and former Minister for Foreign Affairs of Kenya. The Taita Research Station aims at facilitating multidisciplinary research and education. Taita Research Station is the first research station overseas owned by the University of Helsinki. New actions are hoped to open opportunities for research collaboration and exchange of staff and students. Community outreach is also said to be an important part of the daily work of the Taita Research Station. A holistic understanding of people and their environment has an evident cultural dimension too (Taita Environmental Research and Resource Arc 2011). Method and the data Interviewing the Locals The need to collect data about the local knowledge of the new Research Station rose from the interest to learn about local attitudes, hopes and opinions toward the new station after the opening ceremony. There was also interest of informing the local community about the newly opened station and its activities at the same time. There was a leaflet given to every person interviewed. The interview study was a half structured set of questions. The order and the formulation of the questions were same for all the interviewees. Interviewees were asked to answer freely. The main questions were: 1. Do you know what is done at the Hebron estate today? 2. How did you learn about the station? 3. Are the station s activities seen in the village life? 4. Could the research have an impact in your life? 5. What do you think about this kind of activity? The interviews were collected from the village where the station is located called Wundanyi. There were a total of 22 interviews done. The interviews were collected incidentally from the adult people in the village during one day with the help of stations local research assistant. Most of the respondents spoke English quite well but mostly questions were asked in two languages, in English and in the local language. The Data Out of 22 respondents 50 percent were women and 50 percent men. Age distribution was between years (Fig 2.). This was to be expected because the target group was adults. 59 percent of the respondents were under 40 years old. 64 percent lived at Wundanyi and 36 percent of the respondents live in other villages of the Taita region. 6

8 I. Locals and the new Station: Local knowledge about the new Research Station Terra at Wundanyi, Taita. Figure 2. Respondents age distribution % Business sector Service/office Farmer Unemployed Teacher Occupation Figure 3. Respondents distribution of occupancy. Most of the respondents (Fig. 3) were working. 41 percent were working at the business sector meaning that they were mostly vendors at the marketplace or little shops. Vendors selling food products were all retailers buying products from the local farmers at Taita region. A total of 36 percent were working at the service sector or office work. Only nine percent (two persons) were unemployed. One was a housewife and the other a college graduate looking for a job. Results About knowledge We wanted to find out if people had noticed the opening of the Station week before and if they had maybe read it on the newspapers or heard about it from friends. Thus, people were asked if they knew what was done at the Hebron estate now. Hebron estate is the name of the Station s property. As table 3 shows almost all the interviewees knew the place (95 percent). This means that only one person did not know the place at all. This is probably explained by the fact that the respondent had moved to the village under a year ago. 7

9 I. Locals and the new Station: Local knowledge about the new Research Station Terra at Wundanyi, Taita. Table 3. Knowledge about the use of the Hebron estate. Knowledge about Hebron estate % Research station 22 Guesthouse/Christian center 32 Bookstore 5 Knew the place but not what is done there 36 Never heard 5 When the interviewees were asked to define the present purpose of the Hebron estate the answers varied a lot. 36 percent of the respondents knew the place but did not know the use of it at all. Almost the same number of people (32 percent) said that it is a guesthouse or/and a Christian center which was the previous use of the place. Only 22 percent new that the Hebron estate serves as a research station now. The 22 percent who knew about the research station were asked how they had learned about the station. No one had read or seen it in the media. 15 percent had done co-operation or business with the station or the people from the station. Rest of them had heard about it from friends. They were also asked what was done at the Station. One respondent did not know what was done at the Station. Rest of them knew that research has something to do with forests, agriculture, animals, plants and nature in general. One of them said that students from abroad come here to study. The knowledge was quite general. 64 percent of the respondents had seen the stations activities in the village life. 36 percent said that they have not seen anything or noticed anything unusual. Station s activities were mostly seen when station s staff or guests had been shopping in the village (food, drinks, renovation supplies etc.). Many had seen the students or researchers in the forests of Taita. Attitudes and hopes We wanted to find out if the locals feel that the Research station could have an impact in their life and also what they think about this kind of activity. Most of the respondents did not know what is done at the Research station so there was a leaflet given and they were told on a general level about the research. After that we asked about their opinions and expectations toward the Station and the research. Overall attitude toward the Station and research was positive. 78 percent were optimistic and positive toward the Station. 22 percent of the respondents did not have any thought of how the Station could impact their life. Also, they did not have any opinion when asked what they think about this kind of activity. One of the respondents did not expect anything from the Station. 8

10 I. Locals and the new Station: Local knowledge about the new Research Station Terra at Wundanyi, Taita. Out of the respondents who were able to name impacts the Station could have, the most important benefit they could think was education. About half of the respondents pointed that the community would benefit most if they were educated at the Station and reported about the results of the researches. All of the respondents named the community as the main beneficiary. If people would get education about the nature, agriculture and forestry they would have better opportunities to act right and improve the current conditions at Taita region. Their answers reflected the real need for concrete things that could improve their current conditions at the area. Research was seen as a key factor on the way to better environment. 15 percent thought that the most important impact will be co-operation and business that the Station will bring in Wundanyi. Retailing agricultural products made the respondents at the business sector also think about the environment. Salesman thinks about the sales but when the climate change and drought hits the agriculture sector it will also hit the retailer. - Man, 35 years - Mostly it was not only business that the retailers were thinking about but the whole picture. They were quite environmentally concerned and had felt the impact of the drought to the area. People hoped that the Station could inspire people to think about the future by promoting the environment because the changes are also felt in the villages. Conclusions and lessons learnt Although I had a local research assistant to help me with the interviews, we need to remember that my presence as an outsider and culturally different person must have impacted the way people answered to my questions. People might have felt that they cannot say negative things while I am around. Still I feel that I got good and quite reliable answers from people. They were able to express their feelings and I think that because of the current environmental conditions, they were truly interested about the new Station and research work. This small-scale research offered three clear results: 1. People at the area are not aware of the new Taita Research station. Mostly people still remember the place as a guesthouse and a missionary house. They do not know the purpose of the Station and need and want information about it. 2. People are hoping that the Station will offer education and report about the results of the researches. They feel that the research should aim to concrete things that they could bring into agriculture, forestry and actions concerning environment. 3. The attitude toward the Station and research is overall positive and hopeful. This kind of activity is appreciated when the community is included in the process. This research showed that the local community needs a clear outreach from the Station. People need information and openness so that they can be merged into this project. Locals are interested in environmental subjects but there must be an effort from the Station to make a connection to them. 9

11 I. Locals and the new Station: Local knowledge about the new Research Station Terra at Wundanyi, Taita. 10

12 II. Ongoing scientific work on forest ecosystems in Taita Hills area a brief description II. Ongoing scientific work on forest ecosystems in Taita Hills area a brief description Henri Riihimäki Abstract This work describes briefly the environmental scientific work which has been done on Taita Hills, an area with a rapidly changing landscape and high biodiversity. The focus of this work is on research concerning forest ecosystems, forest vegetation, structure, dynamics and health. I compiled information about the permanent plots which have been established in the above mentioned area. These plots are an excellent tool for scientists to monitor the ongoing, rapid changes. Much of this work is based on personal communication with different researchers. Introduction Taita Hills are located on SE-part of Kenya. They are a part of the so called Eastern Arc Mountain chain, which has been considered as one of the biodiversity hot spots of the world (Rogers et al. 2008). Much of the original forest cover has been destructed and only small forest fragments remain. It has been estimated that 98 % of the original forest cover has been lost over the past 2000 years, most of it during the last 250 years (Rogers et al. 2008). Three relatively large forest areas remain; Ngangao, Mbololo and Chawia. Their size varies between 86 and 200 hectares. In addition there are less than ten smaller patches whose size is between <1 and 16 hectares (Aerts et al., 2010) Despite the dramatic changes, these forest fragments still boast a very high level of endemism, both in flora and in fauna, and are in great importance for biodiversity conservation. Monitoring the ongoing changes and their effects on biodiversity and forest structure (i.e. biomass, tree densities) is very important and permanent plots come to great importance from this perspective. According to Baker et al. (1996) long term observations from permanent plots are the most appropriate way to evaluate vegetation developments over time. With this method, one can for example clearly monitor undesirable developments caused by external influences. In addition to biodiversity, the forests are in great importance from a hydrological perspective. The mountain top forests regulate the water flow from the hill tops to the valleys and therefore they are vital to valley s municipal communities and its agriculture too. Without the forests, hydrological conditions would become extreme and this would endanger the steady supply of water and expose the areas to drought. Vegetation cover also protects the soil from erosion. Without vegetation the soil is exposed to surface water and its eroding power. It has been detected that both gully density and the length of the gullies have increased in the recent decades (Pellikka et al. 2005), which is a strong signal of a growing erosion problem. The importance of the forests is self-evident, and it is no wonder a lot of research has been done on the area. Most of the work has concentrated on the indigenous forests, but more recently exotic forest plantations and agro-forestry areas have also been subject to research (Omoro 2011, Thijs 2011a). 11

13 II. Ongoing scientific work on forest ecosystems in Taita Hills area a brief description FHM and FIA-proctocol plots Ngangao and Chawia areas have been studied by a research group led by Dr. Gerald Hertel. There are also other research areas (a total of 26 plots) on the Eastern Arc Mountains, located in Usambara and Uluguru mountains, Tanzania (Fig. 2, Madoffe et al. 2008:10). Hertel s group measured tree condition, size, species, crown condition and regeneration. Their research covers only indigenous forests, concentrating on attributes related to forest health. According to Madoffe et al. (2008:3) their goal was to make the information available to others for continuous study of Eastern Arcs forests as well as potential sites for other studies that might require information on how the forests are changing over time. Forest health was examined by three main indicators; mensuration, visual crown ratings, and tree damage. By mensuration they described the forest condition in regard to growth, regeneration, and mortality. Measured variables were the diameter at breast height (hereafter DBH), tree height, and relative crown position within the forest. Size variable results are specific for different tree species. Health of the forest was examined visually by the condition of the tree crowns and damage to the tree trunks. In visual crown rating they assessed the live crown ratio, crown density, crown dieback, and foliage transparency (for more details see Madoffe et al. 2008). Level of vigority (low, moderate or high) of the saplings inside the sub- and microplots was also evaluated. Their measuring method was developed in USA for monitoring forest health by US Forest service (USDA, 1999) and then applied with minor changes to East-African forests (Madoffe et al. 2008). First measurements in February 2000 were done according this protocol. The protocol was then changed and it became a subset of the Forest Inventory and Analysis program (USDA, 2000). This resulted to some minor changes in protocols, but did not affect the overall plot layout and basic tree measurements (Madoffe et al 2008). Plots that were established later were done according to this protocol. They concluded that the protocols were useful for tropical forests as well. In 2001 they established more plots and at the end they had 18 plots on Taita Hills area (Fig. 1). Plots that were done on the early 2000s were re-measured in September and October 2006 to see how they had changed. By re-measurements one can investigate growth dynamics and monitor the changing health conditions of the forests. For further information, see Rogers et al. (2008). Their plan is to start re-measure the plots again in 2012 for further review, three plots at a time (Rogers, 2011). Eleven of the plots are located on Ngangao and seven plots on Chawia forest fragment (Fig. 1 3). Plot locations were chosen randomly (Madoffe et al. 2008: 9). The size of the plots is one hectare each. Each of these plots has four subplots as can be seen from Fig. 2. The size of the subplots is ha each. From the subplots DBH was measured. Data was collected from tree individuals whose DBH were greater than 12.7 cm. Total basal area of the trees and their growth rates will be computed from DBHs (Rogers, 2011). The dead proportion of trees DBH was also measured in addition to living trees. 12

14 II. Ongoing scientific work on forest ecosystems in Taita Hills area a brief description Figure 1. Plot location of FHM-group and Loice Omoro. Plot location, and indigenous forest data from Siljander & Pellikka, For details about the digital elevation model data see (Pellikka et al., 2005). Inside each subplot is one microplot, where data on saplings and seedlings have been collected. Size criteria for saplings was set to cm (DBH). Limit for a coniferous seedling was a minimum length of 15 cm and DBH less than 2.54 cm. DBH on hardwood seedlings was the same, but a length criterion was set to 30 cm. More precise information about plot structure and variables from plots can be found on Madoffe et al. (2008). Mrs. Loico Omoro continued this work and measured forests with the same protocol in the years (Omoro 2011). Omoro created new plots to Mbololo, Irizi, Chawia and Ngangao Figure 2. The structure doffe et al. 2008) 13

15 II. Ongoing scientific work on forest ecosystems in Taita Hills area a brief description areas. With her work the exotic forests were taken into account as well. Subplots were created for pine, eucalyptus and cypress forests, respectively. In Mbololo new indigenous forest plots were also created in addition to the Ngangao and Chawia plots. By including Mbololo, all the major forest fragments are now under FHM surveillance (Fig. 1). Belgian and Finnish plots Indigenous forests among other forest types have been researched by mr. Koen Thijs and his students also. A total of 85 permanent indigenous plots have been established. In addition to the indigenous plots, 70 exotic forest plots have been measured (Thijs, 2011a). Their work in Taita Hills began on January 2009 and it s still ongoing. According to Thijs (2011b) the permanent plots will be revisited every five years. The indigenous plots are sized 20 x 20 meters. From these plots a thorough research has been carried out on both biotic and abiotic features. Each plot includes a subplot of 10 x 10 meters. Trees were counted and measured (DBH) from the whole plot, while shrubs were counted from the subplot only. Seedlings were counted from five different 1m 2 plots. Results are given as units per hectare. Notes from terrain features were also taken including rock, canopy, shrub, herb and litter cover. Litter thickness was measured as was soil penetration too. Any signs from human activity were also written down (harvesting, grazing of cattle, etc.) They also measured ph, conductivity (µs/cm) of the soil, and the amount of phosphorus, nitrogen and carbon in it. Hemisphere photographs were taken for leaf cover analysis and for the caulculatio of Leaf Area Index (LAI). Mr. Pekka Itkonen from University of Helsinki followed Thijs footsteps in his MSc thesis work (an unpublished manuscript; see also Chapter III). A total of 18 new plots were established (see Fig. 3). Nine of these were classified to woodland and another nine to agroforestry type. From these plots the measured variables were DBH by tree species, height of trees, shrub count, crop species (agroforestry plots), and seedlings and saplings (count and species). Plot structure was as on Thijs plots. It is worth to mention that different researchers use different land cover classifications, and different criterions for different classes (e.g. indigenous forest). 14

16 II. Ongoing scientific work on forest ecosystems in Taita Hills area a brief description Figure 3. Plot locations for Thijs (n = 165) and Itkonen (n = 18). Plot location data from Itkonen (2011, unpublished). In addition to the above mentioned plots, 600 transect points have been measured (Thijs, 2011b). Transects were located 200 meters from each other, and the distance between points was 150 meters. From these points the Belgian group measured biotic and abiotic characters and made a land cover classification (LCCS). Location of these transects is roughly in the middle of Ngangao, Chawia and Vuria forest fragments (Thijs, 2011b, Fig 3.). 15

17 II. Ongoing scientific work on forest ecosystems in Taita Hills area a brief description Conclusions A comprehensive network of permanent plots has been established on Taita Hills area by different researchers. The work began from indigenous forests and was later continued to exotic forests. The gradient of the plots is now vast and covers a large amount of the total area as we can see from Fig. 1 and Fig. 3. The coverage of the plots gives very good overview from Taita Hills different forest types now that exotic forests have been taken under research too. From these plots many several variables have been measured and described. Most of the mensuration work is related to trees, while shrub, field and ground layers and their species dynamics and ecology have gained less attention and precision in the field work that has been done. A more precise mapping of these layers could be one focus point for future researchers. Permanent plots enable monitoring over time. This type of work has already been done by Dr. Hertel s group and will be followed by Mr. Thijs group in the future. In addition to the described in situ measurements a lot of remote sensing and geoinformatic system analyses have been done on the area (see e.g. Pellikka et al., 2009 & Gonsamo, 2009). When combined with the in situ measurements we can do multiple different analyses that are very valuable. A good, detailed picture of the ground truth is needed and therefore it is very pleasing to see that the permanent plot network is so vast today. The unique nature of the area guarantees that Taita Hills, and its forests will be a hot topic in the future too. There is a huge amount of scientific work that waits to be done in the future. With the existing field and remote sensing data, and with the new facilities of University of Helsinki in Wundanyi, the opportunities for any type of future work are excellent. References Aerts R., Thijs K.W., Lehouck V., Beentje H., Bytebier B., Matthysen E., Gulinck H., Lens L., Muys B Woody plant communities of isolated Afromontane cloud forests in Taita Hills, Kenya. Plant Ecology 212, Baker. J.P., Olff, H., Willems, J.H. & Zobel, M. (1996). Why do we need permanent plots in the study of long-term vegetation dynamics? Journal of Vegetation Science 7, Gonsamo, Alemu (2009). Remote sensing of leaf area index: enhanced retrieval from closerange and remotely sensed optical observations. University of Helsinki Academic dissertation. Madoffe, Seif, Paul C. Rogers, Barbara O Connell, James Mwang'ombe, Kathy M. Tillman & Gerard Hertel (2008). Forest Health Monitoring in the Parts of the Eastern Arc Mountains of Kenya and Tanzania: a baseline report on selected forest reserves - CEPF Final report. <

18 II. Ongoing scientific work on forest ecosystems in Taita Hills area a brief description Omoro, Loice (2011). Data and plots of Taita Hills. <omoro@mappi.helsinki.fi> Personal . Pellikka, P.K.E., B.J.F. Clark, T. Sirviö & K. Masalin (2005). Environmental change monitoring applying satellite and airborne remote sensing data in the Taita Hills, Kenya. In Röder Achim & Joachim Hill (eds.). Proceedings of the 1st International Conference on Remote Sensing and Geoinformation Processing in the Assessment and Monitoring of Land Degradation and Desertification. Trier, Germany, September, 2005 Pellikka, Petri K.E., Milla Lötjönen, Mika Siljander & Luc Lens (2009). Airborne remote sensing of spatiotemporal change ( ) in indigenous and exotic forest cover in the Taita Hills, Kenya. Rogers, Paul C., Barbara O Connell, James Mwang ombe, Seif Madoffe & Gerard Hertel (2008). Forest health in the Ngangao forest, Taita Hills, Kenya: A five year assessment of change. Journal of East African Natural History Rogers, Paul C. (2011). Data and plots of Taita Hills. <p.rogers@aggi .usu.edu> Personal . Thijs, Koen (2011a). Data from Taita Hills. <Koen.Thijs@ees.kuleuven.be> Personal . Thijs, Koen (2011b). Data from Taita Hills. <Koen.Thijs@ees.kuleuven.be> Personal . USDA Forest Service (1999). Forest Health Monitoring 1999 Field Methods Guide. USDA Forest Service, National Forest Health Monitoring Program, Research Triangle Park, NC USDA Forest Service (2000). Forest Inventory and Analysis National Core Field Guide, Version 1.5. USDA Forest Service, Research Triangle Park, NC

19 II. Ongoing scientific work on forest ecosystems in Taita Hills area a brief description 18

20 III. On the vegetation composition and structure of the forests, woodlands and agroforestry areas of Taita Hills, SE Kenya III. On the vegetation composition and structure of the forests, woodlands and agroforestry areas of Taita Hills, SE Kenya Pekka Itkonen Abstract The Taita Hills region of southeastern Kenya has undergone severe fragmentation, degradation and losses of forest. Once covered with extensive indigenous forests, only small isolated remnants on hilltops remain. Exotic species have been planted in forest plantations and in the midst of cultivation, constituting agroforestry areas. Conversion of indigenous forests into exotic forests has altered the vegetation composition and structure of the forests, deteriorating important ecosystem services, such as water supply and biodiversity. When comparing the physical properties of the trees of a total of 18 woodland and agroforestry plots 0.04 ha in size, average stem densities of the plots were found to be rather equal, unlike mean tree height, diameter at breast height and tree basal area. Introduction The indigenous afromontane cloud forests of the Taita Hills have undergone considerable disturbance, degradation and deforestation during the last century due to increased population pressure and ineffective conservation management. In pre-colonial times the forests were cleared mainly for agricultural use. During the British occupation, railway construction demanded lots of firewood and timber. Heavy post-colonial population increase has further intensified the need for firewood, timber and clearing for agricultural areas and livelihoods (KFMP 1994: 39). The deforestation has been compensated by extensive plantations of exotic trees to fulfill the increasing need for timber and firewood of the local people. Although plantations have proven to be a successful way to prevent major losses in total forest area, the conversion of indigenous to exotic forests alters the original vegetation composition and structure of the forests (Wilder et al. 1998: 185; Pellikka et al. 2009: 226; Omoro et al. 2010). This, in turn, has quite dramatic ramifications on the biodiversity and other ecosystem services, such as water supply of the forests. Study Area The Taita Hills constitute the northernmost outreach of the Eastern Arc Mountains, a chain of Precambrian crystalline basement mountains, reaching from Udzungwa Mountains in southcentral Tanzania to South-Eastern Kenya (Burgess et al. 2007: ) (Fig. 1 and Fig. 2). Located in the midst of arid and semi-arid Tsavo plains (3 40 S, E), the Taita Hills stand out as verdant islands partially covered by indigenous and exotic forests, supporting and sustaining agricultural lifestyle. The surrounding plains lay at m above sea level, while the highest peak of Taita Hills, Vuria, reaches up to 2208 m. The vegetation and land use of the Taita Hills is predominantly governed by ecological zonation due to relief and spatial fluctuations in rainfall and temperatures (Seppä 1990: 7; Pellikka 2004: 75). 19

21 III. On the vegetation composition and structure of the forests, woodlands and agroforestry areas of Taita Hills, SE Kenya The rainfall pattern comprises two annual rainy seasons, being mainly affected by the positions of the Sun and the differences in air pressure between the African continent and the Indian Ocean. The longer rainy season takes place in March May, when the moist southeastern trade winds penetrate inlands, causing orographic rains. The Intertropical Convergence Zone (ITCZ) shifts northwards along with the zenith position of the Sun, which produces convection precipitation (Seppä 1990: 7). The shorter rains occur in November December. Brought by the north-eastern trade winds crossing the Horn of Africa, the short rains are not as intense as the long rains (Seppä 1990: 7). The orographic rainfall pattern results in an umbrella effect, southeastern slopes receiving more precipitation than northwestern slopes. Thus, the isohyet of 900 mm of annual rain, restricting the occurrence of indigenous cloud forest fragments, lies above 1400 m altitude at southeastern slopes and above 1700 m altitude at northwestern slopes (Pellikka et al. 2009: 222). The average annual rainfall between 1986 and 2003 in Mgange (1768 m a.s.l.) and Voi (560 m a.s.l.) was 1132 and 587 mm/a, respectively. (Pellikka et al. 2009: 222). Some years one or even both of the rainy seasons do not occur at all, or the rains might fall heavily during a short period of time. There are no dry seasons in the cloud forests at hill peaks, however, due to cloud precipitation occurring throughout the year (Pellikka et al. 2009: 222). The temperatures are affected primarily by the altitude. The annual mean temperature of Voi (560 m a.s.l.) is 24.9 Celsius, while at Wesu peak (1675 m) it is only 16.4 (Kivikkokangas- Sandgren et al. 1990: 2). Adequate precipitation and the comfortable temperatures of Taita region make it a desirable habitat compared to its surroundings. This has resulted in increasing population density and intensified land use. The steep hills are subject to cultivation of crops such as coffee, maize, mangoes, tomatoes, cassava, bananas and beans (Beentje 1988: 24). Cabbages and fodder crops, such as Napier grass, are common, too. Most advanced small-scale household farms are terraced and drenched, but some shifting cultivation is still practiced due to abandoning eroded and degraded sloping fields. 20

22 III. On the vegetation composition and structure of the forests, woodlands and agroforestry areas of Taita Hills, SE Kenya Figure 1. The Taita Hills region is located in south-eastern Kenya. The area bordered by a black rectangle is depicted in greater detail in figure 2. (Map Library 2011; WRI 2011). Figure 2. The Taita Hills rise from the surrounding Tsavo plains lying at the altitude of ca. 500 m above sea level. The highest peak of the Dabida massif, Vuria, reaches up to 2208 m. Mt.Kasigau and Sagalla are separate from the main massif (Pellikka et al. 2009; WRI 2011). 21

23 III. On the vegetation composition and structure of the forests, woodlands and agroforestry areas of Taita Hills, SE Kenya Materials and methods This report is based on literature review and field work carried out in January March A total of 18 plots were surveyed in the agroforestry and woodland areas of the Taita Hills, 9 plots in both land cover types (Fig. 3). The plot size was 20 m x 20 m (0.04 ha), and the plot locations were arbitrarily chosen to be representative and to cover the variety within the land cover types. All trees having the height of 5 m or more were identified and measured for their height and DBH (diameter at breast height i.e. 1.3 m). Shrubs (height 1 5 m) and crops were identified and counted in 10 m x 10 m subplot. Figure 3. The indigenous and exotic forests, agroforestry and woodland areas of the Taita Hills according to Pellikka et al. (2009), and the plots surveyed. The total area of the classification covers ha. The remaining indigenous forests cover only 726 ha, while exotic forests cover 1312 ha. The total coverage of woodland and agroforestry areas are 1409 ha and 1847 ha, respectively. Note that the classification does not cover Sagalla and Mt. Kasigau. 22

24 III. On the vegetation composition and structure of the forests, woodlands and agroforestry areas of Taita Hills, SE Kenya Indigenous forests The indigenous forest patches of the Taita Hills are described as remnants of the original afromontane forest. (Aerts et al. 2010: 639). In Kenya Forestry Master Plan (KFMP 1990: 42) the Taita Hills forests are classified as a part of Kenya s dry indigenous forests. Food and Agriculture Organization of the United Nations (FAO) defines indigenous forests in its country report on Kenya as follows: A group of trees whose crowns are largely contiguous and include the ecosystem that makes it up and a tree canopy cover of over 10% and the canopy is essentially of indigenous tree species growing under natural conditions and excludes planted indigenous plantation forests. (FRA 2010: 7). Niemelä s (1988: 62 63) definitions of both moist and dry lower montane forests match the observed characteristics of indigenous forests of Taita: the moist forests occur in southeastern slopes receiving mm of annual precipitation, species such as Lobelia gibberoa, Dracaena steudneri and Cyathea manniana being characteristic to them. The dry lower montane forests occur in northern and western slopes, receiving mm of precipitation a year. Indigenous forest loss The indigenous forests of the Taita Hills are nowadays restricted to three isolated remnants and nine smaller patches, but there may once have been hundreds of square kilometers of continuous cloud forest covering the Taita Hills (Pellikka et al. 2009: 221). The forests are located on the main massif, Dabida Hill, and on two isolated hills, Mount Sagalla and Mount Kasigau (Aerts et al. 2010: 641) (Fig. 2 and Fig. 3). The estimations of the area of the remaining indigenous forest vary depending on methods and definitions used. Some estimation of patch areas is presented in Table 1. According to Pellikka et al. (2009), between 1955 and 2004, the total forest area of the Taita Hills has decreased by only 2 %, but the total area of indigenous forest has diminished by no less than 50 % (total area ha in 2004). This is a result of conversion of indigenous forests into exotic forest plantations and agricultural land. Also non-forested areas have been extensively converted to exotic plantations. Table 1. The most remarkable patches of indigenous forest remaining in the Taita Hills. Area (ha) Disturbance Source of surface area Mbololo 185,0 Low Omoro et al Ngangao 124,8 Medium Pellikka et al Kasigau >100 Low Bytebier 2001 Chawia 90,5 High Pellikka et al Yale 17,8 Medium Pellikka et al Macha 5,4 Medium Pellikka et al Fururu 5,00 Medium Wilder et al Mwachora 4,50 Medium Pellikka et al Sagalla 4,00 Medium Wilder et al Ronge 1,00 Medium Wilder et al Vuria 1,0 High Wilder et al Ndiwenyi <1 High Aerts et al Kichuchenyi <1 Medium Aerts et al

25 III. On the vegetation composition and structure of the forests, woodlands and agroforestry areas of Taita Hills, SE Kenya Indigenous forest flora The most important woody indicator species of indigenous moist montane forests of Taita Hills are Tiliacora funifera, Chassalia parviflora, Ochna holstii, Craibia zimmermannii, Landolphia buchananii, Cola greenwayi, Newtonia buchananii, Tabernaemontana stapfiana, Strombosia scheffleri, Nuxia floribunda, Rauvolfia mannii, Syzygium sclerophyllum, Macaranga conglomerata, and Keetia guinenzii. The list above comprises species of trees, shrubs and lianas and is based on the results of Aerts et al. (2010). Other common indigenous species are Albizia gummifera, Phoenix Reclinata, Xymalos monospora, Syzygium guineense, Maesa lanceolata, Lepidotrichlia volkensii, Aphloia theiformis, Syzygium guineense and Cyathea manniana. Although there are differences in plant communities between patches of indigenous forests, at landscape level the isolated fragments constitute one plant community, which Aerts et al. (2010: 644) identifies as (secondary) moist montane to intermediate montane forest. This forest type is usually characterized by occurrences of Ocotea usambarensis and Podocarpus latifolius, but the Taita forests have been subject to selective logging of those and lacking large-diameter individuals of the species in question (Aerts et al. 2010: 644). The Taita Hills forests are known to have similar flora to other Eastern Arc Mountains. The vegetation of the forests can be classified either as upland moist forest or upland mist forest (Beentje 1988: 25). The Eastern Arc forests as a whole have strong affinities to the Guineo- Congolian forests of western and central Africa (Rogo & Oguge 2000: 522 cit. Lovett 1993). Ecosystem services of the indigenous forests The Taita indigenous forests - and Eastern Arc montane forests in general - are known for their high levels of endemism and biodiversity, and they are recognized as one of the world s top 25 biodiversity hotspots (Rogo & Oguge 2000: 522). At least 13 species of plants, 3 birds, 1 snake, 3 frogs, 1 monkey and 3 butterflies are known to be endemic to the Taita Hills (table 2) (Rogo & Oguge 2000: 522). Due to their high biodiversity and species richness, the forests serve as valuable gene banks (Rogo & Oguge 2000: 522). Another very important ecosystem service of the indigenous forests is acting as a water supply. The vegetation of indigenous forests intercepts moisture, reducing surface flow of water and raising ground water levels (Pellikka 2004: 80). Surface vegetation also binds the soil and thus reduces erosion significantly on the steep hills prone to land degradation. Some forests of the Taita Hills are also regarded as sacred by the local community. Disturbance of the indigenous forests The remaining Taita forest patches have undergone different levels of human-induced disturbance, such as logging, grazing and fire (table 1). The level of disturbance is high in Chawia, medium in Ngangao and low in Mbololo (Omoro et al. 2010: ). Mount Kasigau has remained undisturbed, Fururu is partly disturbed, Macha, Mwachora, Kichuchenyi and Yale are disturbed and Vuria and Ndiwenyi are heavily disturbed (Bytebier 2001: 24). Disturbances affect and alter the original species composition of the forests. Especially selective logging alters the vegetation composition and structure, for some species are more desirable for logging than others. On the other hand, disturbance may even increase species diversity. Such is the case of temporarily increased amounts of nutrients and light through canopy gaps due to fires (Hobbs & Huenneke 1992: 327). 24

26 III. On the vegetation composition and structure of the forests, woodlands and agroforestry areas of Taita Hills, SE Kenya Table 2. Plant species endemic to the Taita Hills forests, their occurrence in distinct patches and their status of vulnerability according to Beentje (1988: 32 33). Mbololo Ngangao Chawia Vuria Ronge Yale Sagalla Status Chassalia discolor ssp. teitensis x x x rare Coffea fadenii x x rare Dorstenia. sp. nov. x vulnerable Impatiens engleri ssp. teitensis x x rare Impatiens teitensis ssp. teitensis x x x rare Memecylon teitense x x vulnerable Millettia oblata ssp. teitensis x x x x rare Psychotria crassipetala x x x rare Psychotria petitii x x x x rare Psychotria sp. B x feared extinct Saintpaulia teitensis x vulnerable Ypsilopus sp. nov. x vulnerable Zimmermania ovata x vulnerable Occurrences of secondary successional species, such as Maesa lanceolata, Phoenix reclinata, Tabernaemontana stapfiana, are associated with disturbance (Chege & Bytebier 2005:233). Indicator species associated with low levels of disturbance, in turn, are Xymalos monospora, Rapanea melanophelos and Syzygium guineense (Omoro et al. 2010: 255). The selective logging of easily-transported trees has resulted in low number of small diameter class trees in Chawia, affecting the structure of the forest and preventing regeneration (Wilder et al. 1998: 183). Mbololo and Ngangao have the highest diversity and equitability indices of the forest patches, indicating low level of disturbance and a healthy diverse species composition (Wilder et al ). Although disturbed, also Sagalla and Ronge have high equitably indices. According to Wilder et al. (1998: 184) this is rather a result of low species richness than diversity. Structure of the indigenous forests According to Niemelä (1988: 63), in moist lower montane forests lianas, epiphytes and Ficus species are plenty. Lianas comprise a considerable portion of the biomass of the canopy and buttresses are common in large trees. The level of epiphyte occurrence is known to increase with increased and more continuous precipitation (Kuuluvainen 1988: 42). The high-level canopy trees found in lowland rainforests are not present: the highest trees reach m in height. Canopies usually are in two to three strata, but in Ngangao and Mbololo also four strata can be found (Wilder et al. 1998:185). This is probably due to lower rates of disturbance, allowing the mature indigenous forest remnants to reach more abundant canopy composition. As indicated in table 3, the stem densities of indigenous forest patches can vary from 300 to 1000 trees per hectare. Stem densities and basal area are strongly affected by human activity. Being the least disturbed forest, Mbololo has the highest mean basal area (77 m²/ha). According to Wilder et al. (1998: 181), the small patches are missing the large diameter trees, while Chawia is losing its small trees subjective to selective logging. Table 3. Some structural characteristics of the indigenous forest patches of the Taita Hills according to Wilder et al. (1998) and Chege & Bytebier (2005). Note that the data on Yale, Macha, Ndiwenyi and Kichuchenyi is based on only one plot on each patch. Values in parenthesis are standard deviations. The results between the two sources should be 25

27 III. On the vegetation composition and structure of the forests, woodlands and agroforestry areas of Taita Hills, SE Kenya comparable, for Chege & Bytebier (2005) claim to have followed the methods used by Wilder et al. (1998). Sagalla Ronge Mbololo Ngangao Chawia Yale Macha Ndiwenyi Kichuchenyi Mean basal area (m²/ha) Stem density (trees /ha) 386(116) 301(116) 578(148) 380(134) 297(95) Mean height canopy trees (m) Mean canopy cover (%) 57(32) 60(31) 72(34) 60(32) 51(34) Number ot tree species Plots sampled Source Wilder et al Chege & Bytebier 2005 Exotic forests Plantation of exotic trees in the Taita Hills is a quite recent phenomenon, the establishment of first plantation forests of Pinus elliottii in Sagalla dating to 1955 (Beentje 1988: 25). Other exotic species planted are cypress (Cupressus lusitanica), eucalyptus (Eucalyptus saligna), pines (Pinus caribea, P. patula), Maesopsis eminii and grevillea (Grevillea robusta). Eucalyptus, pine and cypress were planted for wood production in extensive plantations, while grevillea was planted mainly among farms. There are also plantations of black wattle (Acacia mearnsii), originally for the tannin industry (Pellikka et al. 2009: 222). The conversion of indigenous forests to exotic forests has occurred in several ways. Some plantations were established in areas where the indigenous forest had disappeared naturally (e.g. due to forest fires), but in some cases the Forest Department has conducted clearings of the indigenous forests to make way for exotic plantations (Beentje 1988: 25). Some plantations have been established in areas found unsuitable for cultivation (Pellikka 1990: 20). Hence there are terraces found in some sloping plantations, e.g. in the eastern slope of Ngangao. There have also occurred under plantings of exotic species among indigenous forests (Beentje 1988: 25). Structure and composition of the exotic forests The vegetation composition and structure of the exotic forests of the study area are not researched and documented as thoroughly as those of the indigenous forests. Usually the plantations mainly consist of one exotic species, but regeneration and under planting of the indigenous species are also present. Omoro et al. (2010: 259) has documented tree stem densities of both exotic and indigenous species in exotic forests of Ngangao, Chawia and Mbololo. The stem densities for eucalyptus and pine forests were higher in Ngangao (2000 and 843 plants/ha, respectively) and Mbololo (1103, 485) than in Chawia (706, 235). However, there were more indigenous species observed in the exotic forests of Chawia than in Ngangao or Mbololo. This may be a result of local geochemical characteristics and the lack of light due to forest denseness in Ngangao and Mbololo (Omoro et al. 2010: 262). In some exotic forests in Chawia, the regeneration of indigenous species is higher than that of the exotic species. The lower diversity in the exotic forests of Mbololo is due to less severe disturbance and fragmentation. Also high stem densities of Acacia mearnsii are common in cypress and eucalyptus forests of Ngangao (

28 III. On the vegetation composition and structure of the forests, woodlands and agroforestry areas of Taita Hills, SE Kenya and 1529 acacia plants/ha, respectively) and in eucalyptus forests of Mbololo (304 acacia plants/ha) (Omoro et al ). The high canopy trees of the exotic forests usually reaches higher than those of the indigenous forests in the Taita Hills. Especially eucalyptus can grow up to 40 m of height. The canopy structure of the exotic forests usually is homogeneous, containing only one or two strata, for the trees are planted simultaneously and having similar growth rate. Thus, it is relatively easy to make a distinction between indigenous and exotic forests from a distance with naked eye, a fact taken advantage of when classifying the forests by utilizing visual interpretation of aerial imagery. In general, the species diversity in Taita Hills is higher in indigenous forests than in exotic forests, but in Chawia the situation is the opposite (Omoro et al. 2010: 261). According to Omoro et al. (2010: 261) this may be due to the fact that the exotic plantations in Chawia have been founded on areas once covered by indigenous forest and currently integrated with indigenous forest. Thus, disturbances have probably stimulated the regeneration of secondary indigenous species, such as Tabernamontana stapfiana, Maesa lanceolata and Phoenix reclinata (Bytebier 2001: 17, 84). Woodlands The concept of woodland is somewhat ambiguous. Areas classified as woodland in Pellikka et al. (2009) cover areas ranging from dry, scarce Commiphora vegetation to stands of denser canopy cover of mixed species. There are also areas of quite dense Acacia spp. and Euphorbia spp. cover, trees reaching barely the height of 5 m and characterized with a rather dense shrub cover. Defining forest or woodland strictly according to its canopy cover of trees, and further defining tree strictly to include only plants with woody stems reaching a certain threshold height (e.g. 5 m) results in excluding areas very similar to woodland as shrubland. The definition of wooded land used in Forest Resources Assessment 2010 Country report (FRA 2010: 7) reads as follows: Land not classified as Forest, spanning more than 0.5 hectares; with trees higher than 5 meters and a canopy cover of 5-10 percent, or trees able to reach these thresholds in situ; or with a combined cover of shrubs, bushes and trees above 10 percent. It does not include land that is predominantly under agricultural or urban land use. The woodlands can thus be seen covering a rather wide continuum between open savannah vegetation and forests. According to Pellikka et al. (2009: 222) woodlands occur below the 900 mm isohyet. According to KFMP (1994: 25) woodlands, bushlands and wooded grasslands occur mainly in the arid and semi-arid areas, but are present in some potential lands, too. Characteristic to these areas are low Acacia spp., Commiphora spp. and Euphorbia spp. trees reaching only 5 to 10 m in height, usually dense and thorny shrub layer and a relatively low species richness. Some characteristics of nine surveyed woodland plots (0.04 ha) are presented in Table 4 and their locations are depicted in Fig. 3. Agroforestry areas Agroforestry means cultivation of plants with woody stems among other cultivated plants, cultivating either simultaneously or by turns (Luukkanen et al. 1988: 164). The trees planted in the fields bind the soil, prevent erosion and give shade to the crops cultivated underneath. In addition, selling trees for timber provides the farmers with a way of earning some extra 27

29 III. On the vegetation composition and structure of the forests, woodlands and agroforestry areas of Taita Hills, SE Kenya funds. The introduction of Grevillea robusta by Danish development workers has proven to be a success. Occurrences of fast- and straight-growing grevillea among farms are very common nowadays. Other trees among crops are fruit trees, such as Musa spp. (banana), Macadamia integrifolia (macadamia), Mangifera indica (mango) and Persea americana (avocado). Also Eucalyptus spp. is found on agroforestry lands, e.g. cultivated together with Napier grass (Pennisetum purpureum) used as fodder for domestic animals. The vegetation structure of the agroforestry areas of the Taita Hills varies considerably between sites. Most dense agroforestry sites would easily classify as e.g. grevillea plantations if it was not for their intensively cultivated undergrowth of crops (tree stem density >800 stems/ha), such as Capsicum sp. and Napier grass. Sites cultivated with e.g. maize (Zea mays) may have rather low stem densities ( stems/ha), trees being planted scarcely in rows on field borders (table 4). Identified tree, shrub and crop species found in total of 18 agroforestry and woodland plots are presented in Table 5. Table 4. Forest structure characteristics in 9 woodland and 9 agroforestry plots (20 m x 20 m) in the Taita Hills region. Standard deviations of mean tree height and mean tree DBH (diameter at breast height) are given in parenthesis. As the locations of the plots are arbitrary and the total count of plots is low, these results should be regarded as indicative rather than fully representative. Plot Basal area Stem density Mean tree Mean tree Plot type name (m²/ha) (trees/ha) height (m) DBH (cm) Site Agroforestry A (6.86) (13.62) Ngangao Agroforestry A (10.88) (18.29) Ngangao Agroforestry A (2.22) (4.56) Ngangao Agroforestry A (2.00) (5.25) Ngangao Agroforestry A (4.79) 27.6 (6.35) Ngangao Agroforestry A (3.08) (5.59) Ngangao Agroforestry A (5.20) (14.58) Fururu Agroforestry A (3.13) (5.32) Fururu Agroforestry A (6.59) (11.69) Fururu Woodland W (1.75) (8.71) Chawia Woodland W (2.21) (7.86) Chawia Woodland W (1.74) 9.66 (5.12) Choke Woodland W (4.23) (9.87) Choke Woodland W (1.06) (6.36) Mwakishimba Woodland W (2.06) (7.13) Mwakishimba Woodland W (1.46) (6.34) Mwakishimba Woodland W (3.32) (26.63) Longolongo Woodland W (0.60) (5.76) Longolongo Agroforestry mean Woodland mean Although the mean stem densities of the agroforestry and the woodland plots surveyed are almost similar, seem the mean tree height, tree basal area and tree DBH to have higher values in the agroforestry plots than in the woodland plots. However, the only variable with a statistically significant difference between the two plot types was plot mean tree height (p < 0.01, one-way analysis of variance). This is probably due to higher precipitation, more potential edaphic conditions and the physical properties of the tree species. The acacia, 28

30 III. On the vegetation composition and structure of the forests, woodlands and agroforestry areas of Taita Hills, SE Kenya commiphora and euphorbia spp. found in woodland plots tend to have shorter and thinner stems than Grevillea robusta, widely found in the agroforestry plots. Table 5. Tree, shrub and crop species found in 9 agroforestry and 9 woodland plots (20 m x 20 m) in Taita Hills. Note that plants with woody stems below the height of 5 m are classified as shrubs. Species found in agroforestry plots Species found in both plot types Species found in woodland plots Trees (>5 m) Shrubs (1-5 m) Crops Cupressus lusitanica Acacia mearnsii Cajanus cajan Eucalyptus sp. Albizia gummifera Capsicum sp. Ficus sycomorus Bersama abyssinica Coffea arabica Macadamia integriflora Bridelia micrantha Dioscorea sp. Macaranga capensis Clausena anisata Mannihot esculentum Malus domestica Dodonea viscosa Musa sp. Mangifera indica Eriobotrya japonica Pennisetum purpureum Ocotea kenyensis Eucalyptus sp. Persea americana Persea americana Ficus sycomorus Saccharum sp. Grewia tembensis Solanum tuberosum Maesopsis eminii Zea mays Millettia oblata ssp. Teitensis Ocotea usambarensis Pentas lanceolata Phoenix reclinata Psidium guajava Psychotria sp. Solanum incanum Grevillea robusta Lantana camara Syzygium guineense Psidium guajava Psychotria petitii Rhus natalensis Turraea robusta Vernonia brachycalyx Acacia senegal Acacia mellifera Acacia seyal Acacia senegal Commiphora africana Acacia totalis Commiphora baluensis Clausena anisata Commiphora lidensis Commiphora baluensis Commiphora schimperi Commiphra africana Dalbergia melanoxylon Dichrostachys cinerea Euphorbia usambarensis Ecobogia capensis Keetia gueinzii Ehretia teitensis Myrica salicifolia Grewia plagiophylla Psidium guajava Grewia plagiophylla Rhus natalensis Heteromorpha trifoliata Schefflera myriantha Ilex mitis Tamarindus indica Keetia gueinzii Terminalia brownii Maytenus heterophylla Vitex sp. Myrica salicifolia Zimmermania sp. Ochna holstii Ocimum gratissimum Ocimum sp. Plectranthus sylvestris Sansevieria sp. Schefflera myriantha Terminalia brownii Zimmermania sp. Conclusions The agroforestry areas and woodland areas of the Taita hills have similar stem densities, but especially tree height is lower in the woodlands. Also basal area of the trees was found to be slightly lower, indicating lower tree volume and thus lower above-ground woody biomass. Both the agroforestry areas and the woodlands cover areas widely varying in vegetation composition and structural properties. The indigenous forest loss and conversion of indigenous forests into exotic forests alters the vegetation structure and species composition of the forests, endangering the biodiversity of 29

31 III. On the vegetation composition and structure of the forests, woodlands and agroforestry areas of Taita Hills, SE Kenya the Taita Hills forests, host to at least 13 endemic plant species. In general, indigenous forests have higher species richness than exotic forests. Further fragmentation, degradation and decrease in size of the habitats endanger the existence of the endemic flora and fauna. The amount of obscure precipitation from mist and clouds depends on the surface area of vegetation. Thus, removing indigenous forest reduces the amount of obscure precipitation (Beentje 1988: 29 30), which may lead to alterations in the microclimate of the area. Some exotic species, such as eucalyptus, demand a lot of water and thus are likely to lower the ground water levels. According to Pellikka et al. (2009: 231), having lower biomass and more scarce undergrowth, the exotic plantations are not as effective carbon sinks as indigenous forests. The comparison of structural properties of the exotic and the indigenous forests in the study area suffers from the lack of data on the structural characteristics of the trees of the exotic forests. According to Omoro et al. (2010: 263), without further disturbance and under planting of exotic species, the exotic plantations may regain their indigenous state by regeneration of indigenous species. Thus, increasing indigenous forest area may be possible through conservation and planting of indigenous species. A special focus should be on the conservation management, for the indigenous forest losses have occurred mainly due to population increase and ineffective conservation (Beentje 1988: 29; Rogo & Oguge 2000: 522). The demand for fuel wood, timber, mechanical wood products and paper is anticipated to continue increasing in Kenya (KFMP: 17 22). Therefore adequate measures of planning and conservation have to be taken in order not to fulfil this demand at the cost of the indigenous forests. References Aerts, R., K. Thijs, V. Lehouck, H. Beentje, B. Bytebier, E. Matthysen, H. Gulinck, L. Lens & B. Muys (2010). Woody plant communities of isolated Afromontane cloud forests in Taita Hills, Kenya. Plant Ecology 212: 4, Beentje, H.J. (1988). An ecological and floristic study of the forests of the Taita Hills, Kenya. Utafiti 1:2, Burgess, N.D., T.M. Butynski, N.J. Cordeiro, N.H. Doggart, J. Fjeldså, K.M. Howell, F.B. Kilahama, S.P. Loader, J.C. Lovett, B. Mbilinyi, M. Menegon, D.C. Moyer, E. Nashanda, A. Perkin, F. Rovero, W.T. Stanley & S.N. Stuart (2007). The biological importance of the Eastern Arc Mountains of Tanzania and Kenya. Biological Conservation 134, Bytebier, B. (2001) Taita Hills biodiversity project report. National Museums of Kenya, Nairobi. Chege, J. & B. Bytebier (2005). Vegetation of four small forest fragments in Taita Hills, Kenya. Journal of East African Natural History Society 94, FRA = Global Forest Resources Assessment Country Report, Kenya (2010). FRA2010/107. Food and Agriculture Organization of United Nations, Forestry department, Rome. Hobbs, R.J. & L.F. Huenneke (1992). Disturbance, diversity, and invasion: implications for conservation. Conservation Biology 6, KFMP = Kenya Forestry Master Plan Development Programmes (1994). Ministry of Environment and Natural Resources, Nairobi. 30

32 III. On the vegetation composition and structure of the forests, woodlands and agroforestry areas of Taita Hills, SE Kenya Kivikkokangas-Sandgren, R., R. Paalanen & S. Tuhkanen (1990; eds.). Taita Hills kuivan savannin ympäröimät vehreät vuoret Kaakkois-Keniassa. Kehitysmaantieteen yhdistyksen toimitteita pp. Kuuluvainen, T. (1988). Trooppisen sademetsän arkkitehtuuri. In Erkkilä, A. & T. Kuuluvainen (eds.): Tropiikin metsät. Silva Carelica 12, Lovett, J.C. (1993). Eastern Arc moist forest flora. In Lovett, J.C. & S.K. Wasser (eds.): Biogeography and ecology of the rain forests of East Africa. Cambridge University Press, Cambridge. Pp Luukkanen, O., V. Kaarakka & T. Saarainen (1988). Näkökohtia kuivien trooppisten alueiden metsätaloudellisista kehityshankkeista. In Erkkilä, A. & T. Kuuluvainen (eds.): Tropiikin metsät. Silva Carelica 12, Map Library (2011). Kenya < Niemelä, T. (1988). Itä-Afrikan vuoristojen metsät ja sademetsät. In Erkkilä, A. & T. Kuuluvainen (eds.): Tropiikin metsät. Silva Carelica 12, Omoro, L., P. Pellikka & P. Rogers (2010). Tree species diversity, richness, and similarity between exotic and indigenous forests in the cloud forests of Eastern Arc Mountains, Taita Hills, Kenya. Journal of Forestry Research 21: 3, Pellikka, P. (1990). Taita Hillsin metsät. In Kivikkokangas-Sandgren, R., R. Paalanen & S. Tuhkanen (eds.): Taita Hills kuivan savannin ympäröimät vehreät vuoret Kaakkois- Keniassa. Kehitysmaantieteen yhdistyksen toimitteita 24, Pellikka, P. (2004). Taita Hills kuivan savannin ympäröimät vehreät vuoret Kaakkois- Keniassa. Turun yliopiston maantieteen julkaisuja 168, Pellikka, P., M. Lötjönen, M. Siljander & L. Lens (2009). Airborne remote sensing of spatiotemporal change ( ) in indigenous and exotic forest cover in the Taita Hills, Kenya. International Journal of Applied Earth Observation and Geoinformation 11, Rogo, L. & N. Oguge (2000). The Taita Hills forest remnants: a disappearing world heritage. Ambio 29: 8, Seppä, H. (1990). Kylien luonnonympäristöt. In Kivikkokangas-Sandgren, R., R. Paalanen & S. Tuhkanen (eds.): Taita Hills kuivan savannin ympäröimät vehreät vuoret Kaakkois-Keniassa. Kehitysmaantieteen yhdistyksen toimitteita 24, Wilder, C., T. Brooks, & L. Lens (1998). Vegetation structure and composition of the Taita Hills Forests. Journal of East African Natural History 87, WRI = World Resources Institute (2011). Download Kenya GIS Data

33 III. On the vegetation composition and structure of the forests, woodlands and agroforestry areas of Taita Hills, SE Kenya 32

34 IV. The misty Cloud forest of Taita hills IV. The misty Cloud forest of Taita hills Petri Nyqvist Abstract The mountains of Taita Hills are too low to support true alpine vegetation. However, the mountains are situated interestingly with respect to moisture concentration and rainfall. This paper gives a basic overview to tropical montane cloud forests (TMCFs) and moist Afromontane forest in Taita Hills. Introduction Taita Hills are situated near the Tanzanian border in southern Kenya. The nearest large mountain is Mount Kilimanjaro ca.110 km to the north-west. The Indian Ocean is ca. 180 km eastwards. The Taita Hills are surrounded by large arid or semi-arid areas, the Tsavo or Serengeti Plains (elevation ca m) and and, with the exception of the isolated Mt. Kasigau, there are no major mountains or highland areas between the Taita Hills and the Indian Ocean. Even the highest peaks of Taita Hills are too low to support true alpine vegetation. However, the mountains are situated interestingly with respect to moisture concentration and rainfall. Thus, even the rather low hilltops and mountain peaks the highest point in Taita Hills is Vuria (2208m) collect abundant moisture. Even tropical montane cloud forests (TMCFs) can be found on some high peaks such as Vuria. In Taita Hills all moist mountain forests have been under heavy forestry and agriculture stress for centuries. As a result, there are only remnants of the original afromontane forests on isolated hilltops and mountain peaks. All the remaining forest fragments are small and in many areas alien tree species (Eucalyptus sp, Pinus sp, Grevillea robusta etc.) have been planted for forestry purposes. The two largest forests are Mbololo (ca. 220 ha) and Ngangao (ca. 120 ha), and the dozen or so smaller forest fragments include Vuria, Chawia, among others. The epiphytic vegetation of afromontane tropical cloud forest in the Taita Hills offers an interesting research topic. These forests, even if small and fragmented, support several different vegetation types and a rich cryptogamic epiphyte flora (Fig. 1). 33

35 IV. The misty Cloud forest of Taita hills What are cloud forests? There is no single definition for cloud forests (also known as fog forests or mist forests). Usually these forests are mainly defined by their nearly constant immersion in a layer of lowlying clouds. Cloud forests are usually found between the latitudes 23 N and 23 S on moist mountain slopes at elevations between 1000 and 3000 m. In some coastal ranges, they can occur at elevations of about 1200 m, and on some small oceanic islands even as low as 500 m (Hamilton, Juvik and Scatena 1994). Annual rainfall in cloud forests may range from 500 to mm and the annual mean temperature is usually from 8 to 20 C (Häger 2006). In addition to vertical precipitation, these forests also receive water from interception and waterstripping of horizontally moving fog. This can often add hundreds of millimetres of water to the forest ecosystem and its watershed (Bruijnzeel and Hamilton 2000). Because of enduring moisture, cloud forests have very unique microclimates (Levia et al. 2011). Figure 1. Fieldwork in submountaine rain forest in Vuria: a) Author collecting samples. b) Tree ferns Cyathea manniana form a dense lower canopy in moist ravines. TMCFs are rare and represent only a small fraction of the world's remaining tropical forests: the current estimate is only ~0.26% of the entire land surface of the planet (Bubb et al. 2004). The potential TMCF area is ~ 2.5% of the worlds tropical forests, whereas actual area estimated in year 2000 was only 1.4% (Bruijnzeel et al. 2010). TMCFs are found in Africa, Southeast Asia, Oceania, South America and the Caribbean. Tropical montane cloud forests generally have high rates of endemism, and many indigenous plants and animals are only found in these forests. Their conservation priority should always be high, as they both maintain water cycles and are rich in biodiversity (Hamilton et al. 2008). 34

36 IV. The misty Cloud forest of Taita hills Globally climate change is a big concern for the future of tropical TMCFs. Some research suggests that the timing, strength, and frequency of cloud cover are currently changing due to rising sea and land temperatures. Some climate models suggest that within the next years, many cloud forests may warm up and dry at extraordinary rates (Bruijnzeel et al. 2010). In Taita Hills most of the forest cover was cleared for agriculture more than 100 years ago (Pellikka et al. 2009). The Taita forests have undergone fragmentation due to the lack of regulations and enforceable rules governing resource use (Rogo and Oguge 2000). Now only marginal remnants of afromontane forest still exist usually near hilltops and in some areas in the close vicinity of tropical cloud forests. Presently all TMCF ecosystems in the Taita Hills are threatened and are in clear need of attentive conservation. Inside the cloud forest The microclimate of tropical montane cloud forests is favorable for epiphytic plants. Concurrently, there are many epiphytic plants growing on the trunks and canopy branches of trees. The forest canopy plays an essential part in forest water balance and ecosystem functioning. Especially in TMCFs the tree canopies and epiphytic plants are important: epiphyte biomass promotes moisture interception, contributes to nutrient cycling, and provides suitable microhabitats for many invertebrates, among other organisms (Levia et al. 2011). The forest canopy is mainly formed by the uppermost layer of forest trees, but also includes all epiphytic plants that live in this canopy layer. Trees reach different heights in different forests and in some TMCFs there are several canopy layers (Bruijnzeel et al. 2010). There are several specialized plant groups that live on TMCFs trees: climbers, epiphytes, hemiepiphytes, and hemi-parasites, for example. Climbers may include vines, lianas, and/or palms, while common groups of epiphytes include bryophytes, lichens, ferns, and orchids. The hemi-epiphytes include the famous strangler figs (Ficus sp.). Epiphytic plants may live entirely on humus layers that form on branches, or spend a part, or all, of their time rooted in soil (Raunkiær 1934, Hamilton et al. 1994). Rainwater and fog reaches the canopy before other parts of the forest, but may also evaporate faster. As a result of this, climate is often quite different in the higher canopy than in the lower sections of the forest. A dense canopy affects the microclimate of the forest by reducing the amount of light and increasing the humidity (Fig. 2). The characteristics of the canopy play a central role in creating the difference you feel when walking from a hot and dry field into a cool, moist forest. At the moment we know very little about Taita mountain cloud forest canopies. As long as these ecosystems remain unexplored, they will most certainly hold undiscovered species. Importance of epiphytic plants In an important article published in 1980 the famous Hungarian botanist Tamas Pócs summarises the importance of epiphytic biomass and its effect on the water balance and humus accumulation in tropical forests of Uluguru Mountains in Tanzania. I suspect that many of the findings in this article should also hold for TMCFs in Taita Hills, even though true elfin forests are only found on the highest peak of Vuria. 35

37 IV. The misty Cloud forest of Taita hills Tamas Pócs (1980) summarized his findings as follows: The epiphytic biomass of submontane rain forest was estimated to be 2130kg/ha dry matter, while its rain intercepting capacity around 1500 l/ha. On the other hand, the epiphytic biomass of a mossy elfin forest at 2120m altitude is near 1400 kg/ha and its intercepting capacity is near l/ha during one rainfall. The aerial humus accumulation is much higher (ca kg/ha) in the elfin forest than in the submontane rain forest (ca 375 kg/ha). There is a positive correlation between the amount of surplus rainfall (the rainfall above 100 mm/month) and that of epiphytic vegetation in rain forest climates. Figure 2. a) Fog interception in Mbololo. b) Pekka Itkonen taking coordinates during fieldwork. Fieldwork and preliminary results from the Taita Hills The cloud forests of Taita Hills should obviously be preserved as forest because they are of prime importance for local water supply, erosion control and biodiversity. It is possible that the loss of these forests would be irreversible because of many complex relationships among their flora, fauna and soil. My own current research interests centre on epiphytic lichens and bryophytes, including both liverworts and bryophytes. I am especially intrigued by the large epiphyte biomass supported by Taita TMCFs, and the capacity of this epiphyte biomass to hold water and to contribute in soil formation. These interesting phenomena have general relevance from the perspective of climate change in tropics. Also some new approaches, such as defining earth microbial metagenomics from different kind of tropical forests and soils would be an interesting area of research (Committee on Metagenomics 2007). In my opinion the Taita Hills would be highly suitable for this type of research because both indigenous afromontane forests and exotic plantations can be found growing side by side. 36

38 IV. The misty Cloud forest of Taita hills During my excursion to the Taita Research Station of Helsinki University in January 2011, I collected a set of lichen and bryophyte specimens from the montane forests of the region. Since then Dr. Johannes Enroth has kindly identified most of the mosses and the liverwort specimens will soon be sent to Tamas Pócs for identification. Also many of the lichen specimens ( >300) should be identified in the near future. References Bruijnzeel, L.A., Scatena, F.N. and Hamilton, L.S. (2010) Tropical montane cloud forests. International hydrology series, Cambridge University Press. Cambridge. Bruijnzeel, L.A. & Hamilton, L.S. (2000) Decision time for cloud forests. IHP Humid Tropics Programme Series No. 13. Paris, UNESCO. Bubb, P., I. May, L. Miles, and J. Sayer (2004). Cloud Forest Agenda.Cambridge. UK: UNEP-World Conservation Monitoring Center. Hamilton, L.S., Juvik, J.O. & Scatena, F.N., eds. (1994) Tropical montane cloud forests. Ecological Studies Series, Vol New York, Berlin, London, Paris and Tokyo, Springer-Verlag. Hamilton, L.S, eds. (2008). Forests and water. FAO forestry paper, Vol Rome. Häger, A. (2006) Einfluss von Klima und Topographie auf Struktur, Zusammensetzung und Dynamik eines tropischen Wolkenwaldes in Monteverde, Costa Rica, Göttingen: Disssertation Georg August Universität Göttingen Levia, D.F. et al. eds. (2011) Forest Hydrology and Biogeochemistry: Synthesis of Past Research and Future Directions, Ecological Studies 216, Pellikka, PKE, Lotjonen M, Siljander M, Lens L (2009) Airborne remote sensing of spatiotemporal change ( ) in indigenous and exotic forests cover in the Taita Hills, Kenya. Int J Appl Earth Obs Geoinf 11: Pócs, T. (1980) The epiphytic biomass and its effects on the water balance of two rain forest types in the Uluguru mountains (Tanzania, East Africa). Acta Botanica Academiae Sientiarum Hungariae. 26: Raunkiær, C. (1934) The Life Forms of Plants and Statistical Plant Geography, being the collected papers of C. Raunkiær. Oxford University Press, Oxford. Reprinted 1978 (ed. by Frank N. Egerton), Ayer Co Pub., in the "History of Ecology Series" Rogo, L., Oguge, N. (2000) The Taita Hills Forest Remnants: A Disappearing World Heritage. A Journal of the Human Environment, 29(8): Royal Swedish Academy of Sciences Committee on Metagenomics. (2007) The New Science of Metagenomics: Revealing the Secrets of Our Microbial Planet. Committee on Metagenomics: Challenges and Functional Applications, National Research Council Further reading Niemelä, T. Tuomo (2011) Vihreä Afrikka kasveja ja kasvillisuutta. Norrlinia 23: Niemelä, T. (1988). Itä-Afrikan vuoristojen metsät ja sademetsät. In: Erkkilä, A. & T. Kuuluvainen (eds.) Tropiikin metsät. Silva Carelica 12,

39 38 IV. The misty Cloud forest of Taita hills

40 V. Some insights to the lichens of the Taita Hills V. Some insights to the lichens of the Taita Hills Annina Launis (neé Mäkelä) Abstract Lichens were collected from the Taita Hills, Kenya, during a one week period in January This work presents the collected lichens with green algae as a primary photobiont. The sample collecting was made in various forest habitats: in indigenous forests, forests with some human influence and in plantation forests. Specimens collected from the rock of the mountain Ngangao are also included. Different habitats as well as species ecology and characteristics of the area are shortly presented. Parmotrema planatilobatum is suggested as a new species to Kenya. Introduction The Taita Hills are characterized by a unique set of climatic and geological features. They rise steep from the vast plains surrounding them and connect to the Eastern Arc Mountains that form an uncontinuous chain from the eastern parts of Kenya to Tanzania. The mountains are geologically old and have sustained forests for tens of millions of years. On the slopes of these mountains numerous species have found a refugium during the climatically unfavourable periods of time. Nowadays, the area is recognized as one of the biodiversity hotspot areas in the world. The Taita Hills are a home for many endemic species of plants, birds, insects and other organisms (Pellikka 2005, Rikkinen 2010). Parmotrema taitae is a lichen species known only from the Taita Hills (Swinscow & Krog 1988). Air currents from the Indian sea provide moisture for the mountains in form of rains, clouds and mist. This, together with suitable temperature and proper amount of light, makes the area ideal for lichens. Both cyanolichens and lichens with green algae as a primary photobiont are diverse and rich in species. Many of the species are found on the other Eastern Arc mountains as well (Pellikka 2005, Rikkinen 2010). Lichen specimens (57) with green algae as a primary photobiont were collected from the Taita Hills during 19th to 22th of January Collecting was made on previously defined sample plots by randomly searching the soil, tree bark, stubs, fallen branches and twigs. The samples were dried, freezed and transported to Finland for identification and closer study. Lichens in the forests of the Taita Hills The forests of the Taita Hills are heterogeneous varying from indigenous rainforests to monocultures of Pinus and Cupressus. Nowadays, only few patches of indigenous rainforest remain in natural condition. Most of the forests have been partly colonized by introduced species such as Pinus patula, Cupressus lusitanica, Acasia mearnsii and species of Eucalyptus. These species have been brought to Taita Hills for various reasons during the past decades or centuries. The introduced species together with increasing land use have changed the area drastically. Forest fires, for example, have become much more common than to what the native species have been adapted to. 39

41 V. Some insights to the lichens of the Taita Hills Lichens have found suitable niches from all of the forest habitats in the Taita Hills, and both species diversity and lichen biomass varies notably between forests. Indigenous forests and forests with only some human impact sustain rich lichen community with large biomass. It seems that genera like Usnea, Heterodermia (Fig.1) and Parmotrema (Fig. 2) are the cornerstones of this biomass. It has been shown that lichen biomass, together with mosses, affects on the water balance of the forests and also vast lowlying areas in the watershed. Large biomass of lichens and mosses help to distribute water more constantly. In this way, natural forests pay a big role in the lives of the local population living in villages on the mountain slopes (Pellikka 2005). Figure 1. Heterodermia leucomelos is a common species in the canopy. Figure 2. Parmotrema planatilobatum is possibly new to Kenya. Parmotrema species in general are common in the canopy and on the base of well-lighted trees. A majority of the lichen specimens collected belong to the genera Heterodermia, Parmotrema, Ramalina, Teloschistes and Usnea. These genera thrive in the dense canopy of indigenous forests and forests with only little human impact. On the other hand, species of Cladonia are more common in open and dryer habitats such as plantation forests as well as on sides of forest paths. The introduced, and since widespread, Acasia mearnsii seemed to be an exellent substrate for many species of different lichen genera. Further, it is possible that some lichen species have actually been introduced to the Taita Hills together with the trees brought to the area. 40

42 V. Some insights to the lichens of the Taita Hills A few specimens of Candelaria, Hypotrachyna, Normandina, Parmelinopsis, Phaeophyscia and Punctelia were also collected. Many of these were found from well-lighted bases of mature trees at open forests or at the edges of forests. In addition, some species were found on twigs that had fallen from the dense canopy of natural forests. Some crustose lichens were collected as well, belonging to the genera Caloplaca, Lecanora and Pertusaria. The precise identification of these specimens is still under work. It seems that Parmotrema planatilobatum (Fig. 2) and possibly Cladonia didyma are new to Kenya. However, it is important to point out that these results should be more carefully looked into. Other interesting records are Hypotrachyna costaricensis and Ramalina fimbriata which are classified as rarities by Swinscow and Krog (1988). A list of all lichen specimens collected is presented in Table 1. Lichens on the rocks of Ngangao On the top of the mountain Ngangao (1957 m alt.) there are large areas of sun exposed acidic rock with sparse vegetation. Mainly due to lack of time, only a few lichen specimens were collected from this very interesting habitat. In addition to the specimens collected, the rock was rich with species of Peltula and Xanthoparmelia. One of the most common lichens growing on the rocks was Caloplaca cinnabarina that covered large areas with its conspicuously orange crustose thallus. The distribution of this species is nearly cosmopolitan and ranges from Southern United States to Africa and some areas of Asia and Australia. The genus Caloplaca is diverse with ca. 600 species worldwide, growing in various habitats on tree bark, soil, rocks and as parasites on other lichens (Nash et al. 2001). A free-living syanobacteria was collected from the rocks of Ngangao. As seen from a distance, it formed large, almost black, vertical belts on the mountain slope (Fig. 3). Microscopy showed a filamentous structure (Fig. 4) similar to that found in the genus Scytonema, among others (Friedl & Bundel 2008). Interestingly, some lichens with no cyanobacterial symbiont of their own, grew on the cyanobacterial mat. Possibly these lichens get nutrients, especially fixed nitrogen, from the free-living cyanobacteria. Extra nutrients would, indeed, be beneficial in this harsh, oligotrophic and sun exposed habitat. The lichens found growing on the cyanobacteria were probably some species of Acarospora and Aspicilia (Fig. 6). In addition, Usnea welwichiana was collected from the site. The species grew on the rock forming yellowish gray, 5 8 cm tall shrub-like thalli. Also other Usnea species greatly resembling U. welwichiana grew on exposed rock surfaces 41

43 V. Some insights to the lichens of the Taita Hills Figure 3. Syanobacteria forming a dark mat on the rock. Yellow species of Acarospora growing on it. Figure 4. Trichomes of free-living cyanobacteria possibly related to Scytonema. 42

44 V. Some insights to the lichens of the Taita Hills Figure 5. Caloplaca species typically have chemical compounds (anthraquinones) whitch react to KOH with a characteristic shade of red. The pictures show apothecial structures with an ascospore and an orange thallus of Caloplaca cinnabarina. Figure 6. Acarospora species typically produce many ascospores in each ascus. 43

45 V. Some insights to the lichens of the Taita Hills Table 1. List of the lichen species collected, with their collection site, plot number and substrate. Acarospora sp. Ngangao On exposed clifftop Aspicilia sp. Ngangao On exposed clifftop Caloplaca cinnabarina Ngangao On exposed clifftop Caloplaca sp. Fururu/Koen 8 Twig on ground Candelaria concolor Fururu/Koen 20 Twig on ground Candelariella sp.? Ngangao On base of Pinus sp., charred forest Cladonia didyma Ngangao, between 32 and 13E On base of Pinus sp. Cladonia didyma Fururu/62E On base of Acasia mearnsii Cladonia fruticulosa Chawia/18E On base of an old Eucalyptus Cladonia fruticulosa? Fururu/62E On base of?prunus africana? Cladonia macilenta s.lato Ngangao/13E On ground, Cupressus lusitanica forest Cladonia macilenta s.lato Ngangao/14E On base of Pinus patula Cladonia ramulosa s.lato Fururu/62E On base of Prunus africana Cladonia ramulosa s.lato Chawia/18E On base of Cupressus lusitanica Cladonia sp. Vuria/90 On decayed stub Cladonia sp. Vuria/93 On decayed stub Cladonia sp. Vuria/96 On base of Acasia mearnsii, rich with syanolichens Cladonia sp. Fururu/Koen 61 On dryish soil Cladonia subdelicatula Vuria/92 On base of an old, small leafed tree Heterodermia hypoleuca/magellanica Vuria/90 On base of Dracaena afromontana Heterodermia isidiophora Vuria/95 On base of Acasia mearnsii, rich with syanolichens Heterodermia isidiophora Fururu/Koen 61 On base of Cupressus lusitanica Heterodermia isidiophora Fururu/Koen 63 Twig on the ground Heterodermia japonica Vuria/91 On base of a tree with bryophytes Heterodermia leucomelos ssp. boryi Vuria/93 Twig on the ground Heterodermia leucomelos ssp. boryi Vuria/on road Twig on the road Heterodermia leucomelos ssp. boryi Fururu/Koen 21 Twig on the ground Heterodermia speciosa Vuria/90 On a fallen Macaranga Heterodermia speciosa Vuria/on road Twig on the road Hypotrachyna costaricensis Vuria/forwards plot 92 On base of Acasia mearnsii Hypotrachyna sp. Ngangao/14E On base of Pinus patula Lecanora sp. Ngangao/32 Twig on the ground Normandina pulchella Vuria/92 On base of Prunus africana, on moss Parmelinopsis minarum Vuria/90 On base of Acasia mearnsii Parmotrema austrosinense Ngangao Near the biggest Newtonia buchanii, on ground Parmotrema crinitum Ngangao/32 Twig on the ground Parmotrema hololobum Ngangao/13E On base of Cupressus lusitanica Parmotrema planatilobatum Ngangao On base of charred Pinus sp. Parmotrema planatilobatum Ngangao On base of charred Pinus patula Parmotrema sp Chawia/18E On base of an old Eucalyptus Parmotrema sp. Chawia/28I Twig on the ground Pertusaria amara Ngangao/13E On base of Cupressus lusitanica Pertusaria sp. Ngangao/32 Twig on the ground Phaeophyscia hispidula Vuria/satula On base of Cupressus lusitanica Punctelia rudecta Vuria/90 On base of Dracaena afromontana Pyrrhospora sp. Ngangao/13E On base of Cupressus lusitanica Ramalina calcarata Vuria/93 Twig on the ground Ramalina celastri Fururu/Koen 20 Twig on the ground Ramalina fimbriata Ngangao/13E On a twig on the ground Teloschistes chrysophthalmus Fururu/Koen 20 Twig on the ground Teloschistes chrysophthalmus Chawia/18E Twig on the ground Teloschistes flavicans Vuria/93 Twig on the ground Usnea sp. Ngangao On a dry twig Usnea sp. Ngangao On a dry twig Usnea sp. Vuria/94 On base of Acasia mearnsii, rich with syanolichens Usnea welwitschiana Ngangao 44 On exposed clifftop

46 V. Some insights to the lichens of the Taita Hills Acknowledgements I wish to thank the organizers prof. Petri Pellikka, prof. Jouko Rikkinen and PhD. Tuuli Toivonen for the memorable and truly mind opening expedition to the Taita Hills. I also want to thank prof. Teuvo Ahti and prof. head curator Soili Stenroos from the Botanical Museum, Finnish Museum of Natural History, for their support and identifications of the Cladonia specimens. Also, curator Leena Myllys was very kind to help me with the samples of Usnea. Literature: Brodo, I., Sharnoff, S.D., Sharnoff, S.S., Lichens of North America. Yale University. Feuerer, T. (ed.), 2010: Checklists of lichens and lichenicolous fungi. Version 1 June Checklist of the lichens and lichenicolous fungi of Kenia. Friedl, T. and Bundel, B. (2008). Chapter 2: Photobionts. In: Nash, T. H. (edi.). Lichen Biology. Cambridge University Press, Nash, T.H., Ryan, B.D., Gries, C., Bugartz, F., (eds.) Lichen Flora of the Greather Sonoran Desert Region. Vol 3. Arizona University State Herbarium. Pellikka, P Taita Hills kuivan savannin ympäröimät vehreät vuoret Kaakkois Keniassa. Turun yliopiston maantieteen laitoksen julkaisuja nro 168. Swinscow, T.D.V. & Krog, H., Macrolichens of East Africa. British Museum (Natural History). Rikkinen, J Taitan vuoristometsien kasvit. pinkka.helsinki.fi 45

47 46 V. Some insights to the lichens of the Taita Hills

48 VI. Lichen herbivory VI. Lichen herbivory Mervi Laitinen Abstract Lichen-feeding animals are scarce. Generally, lichens are pretty nutrient-poor, have low energetic value and defend themselves against herbivores. Still, some animals are able to ingest lichens. Others are generalist while others are specialist lichenivores. Lichenivorous animals are found among insects, gastropods, mites and mammals. Herbivore grazing is usually fairly minimal, but in some cases grazing can even shape the distribution patterns of lichens. Introduction Lichens are symbiotic organisms that are formed by a fungus and usually by a green alga or cyanobacterium. They often populate habitats that are harsh and therefore usually free from plant-cover. In these kinds of habitats, herbivore pressure can be directed to lichens. Hence, many lichen species defend themselves against herbivores by producing antiherbivory compounds, or by having a low nutritional value. Quite few herbivores have adapted to use lichens as a food source and generally lichens avoid extensive grazing. On the other hand, small grazing marks are often seen in nature (Gauslaa 2005). In my master s thesis, I am studying cyanolichens of the Taita Hills, Kenya. I examine the variation in grazing pressure between different lichen species and different habitats. Furthermore, I observe what kind of grazing tracks are found on lichens and in which part of the thallus they commonly occur. Lichens as a food source Lichens are sometimes heavily grazed on calcareous rocks which can be inhabited by lichenspecialist molluscs and oribatid mites that consume lichens heavily. Typically, lichens face strong grazing pressure mainly in the northern areas where they are important food source for reindeer (Rangifer tarandus)(gauslaa 2005). Reindeer are one of the few vertebrates specialized on lichen diet. In the winter time, they are able to feed exclusively on lichens because of their rumen bacteria that are able to grow in spite of the lichen compounds. Also many generalist herbivores, such as bank voles (Myodes glareolus), include lichens in their diet. Generalist herbivores do not usually tolerate lichen compounds as well as specialist lichen-feeding animals. For example usnic and stictic acid prevent voles from grazing the lichen. Since lichens with higher concentrations of nitrogen and phosphorus have generally stronger herbivore-defence, herbivores such as some slugs prefer lichens with low nutritional value. Lichen compounds can be even lethal for some animals. Poisoning by Xanthoparmelia chlorochroa has been proposed as the reason for hundreds of elks (Cervus helaphus) dying in the USA in 2004 (Nybakken et al. 2010). Among primates feeding on lichens is unusual. All lichen-feeding primates live in montane habitats, but surprisingly such primates are rare in Afromontane habitats, even though lichens are common. One African primate is Colobus angolensis which inhabits mountainous rainforests in southern Rwanda and other parts of eastern and central Africa does feed on 47

49 VI. Lichen herbivory lichens. One interesting lichenivorous primate is the snub-nosed monkey (Rhinopithecus bieti). Snub-nosed monkeys live in the temperate regions in China and include lichens in their diet through the year. Over half of their annual food consists of the lichens Parmeliaceae. In winter, when other food sources are scarce, lichens dominate the diet. They are stable fallback food for monkeys due to their year-round availability, abundance and nutritionalenergetic properties. Lichens are rich in vitamin D and comparatively easy to digest. The low protein content and lichen toxins on the other hand possibly require monkeys to feed on other, non-lichen food sources as well. Monkeys thrive on high altitudes despite of the colder temperature because there lichens are more abundant. Snub-nosed monkeys tend to form large packs and it has been suggested that the high availability of lichens keeps competition low and enables grouping (Grueter 2009). Herbivore defence Eight percent of the land surface is dominated by lichens, but still few herbivores are able to consume lichens (Nybakken et al. 2010). Several lichens have strong herbivore defence or low nutritional value; therefore food can be a limiting resource to herbivores even though lichens would be very abundant. The defences of lichens usually lie in their secondary fungal compounds. These compounds may have antimicrobial qualities as well and they might protect lichen from solar radiation. Nitrogen-rich cyanobacterial lichens on the other hand, have often low amount of lichen compounds. It has been suggested that for example most Peltigerineae lichens have lost the ability to produce secondary metabolites and they may protect themselves against herbivores with extracellular superoxide. In Peltigera canina wounding of the thallus induces superoxide production (Gauslaa 2005). Many lichen species allocate chemical herbivore defence in reproductive parts such as soralia, which produce asexual diaspores. For example, Lobaria scrobiculata has a five times higher concentration of meta-scrobiculin in the soralia compared to the other parts of the thallus. In a grazing experiment a lichen-feeding snail avoided the soralia, but when secondary compounds were removed the snail preferred these reproductive structures. Also the soralia of the lichen Pseudocyphellaria crocata are avoided by gastropods. A welldeveloped herbivore defence in diaspores probably transfers into the new young thallus and improves the fitness of the lichen. In some lichen species younger parts of the thallus have higher concentration of lichen compounds. Probably young parts are more nutrition-rich and are valuable to the fitness of the lichen (Asplund, Solhaug & Gauslaa 2010). Usually the senescent and damaged parts of the lichen have the lowest levels of secondary compounds and are therefore preferred by herbivores (Asplund, Larsson, Vatne & Gauslaa 2010). Herbivore influence on lichen communities It has been recently detected, that gastropod grazing influences the distribution of epiphytic lichens on a tree trunk and within the forest. Grazing pressure is strongest near the ground and decreases towards the treetop. Snails rarely climb very high along the trunk, with the exception of some very large slugs. Gastropod preferences for different lichen species is poorly known, but in four Lobaria species clear differences in preference have been detected. L. scrobiculata is the most palatable followed by L. amplissima. Less palatable lichens were L. pulmonaria, that has a high concentration of stictic acid, and L. virens which has an unknown defence mechanism. Gastropod preferences shape the distribution of these lichens in nature. L. scrobiculata occurs mainly in forests with low gastropod abundance and on bark 48

50 VI. Lichen herbivory with slightly lower ph because gastropods avoid acidic litter. L. amplissima is found in gastropod-rich localities, but above the lover parts of the tree trunk. L. pulmonaria and L. virens grow both near the ground and on the higher parts of the trunk. Lichens face different grazing pressure within the forest depending on the microhabitat. Gastropods can be widespread for example under more shading canopies. Herbivore grazing may have the largest effect on juvenile thalli because of their lower herbivore defence compared to mature ones. Thereby herbivores can limit the establishment phase of the lichens (Asplund, Larsson, Vatne & Gauslaa 2010). In southern Sweden and Norway the abundance of two lichens, L. scrobiculata and P. crocata preferred by gastropods, has declined strongly. The main cause of declining is probably air pollution, but herbivore grazing may have strengthened it. Also climate change and prolongation of the gastropods grazing season can well have part in the declining pattern (Asplund, Larsson, Vatne & Gauslaa 2010). Grazing marks A high proportion of the cyanolichens collected from Taita Hills have some kind of grazing marks. Usually marks are small, but occasionally grazing has caused major damage to the lichen (Fig. 1). Fairly often also the spore-producing bodies, apothecia, are grazed (Fig. 2). These parts have most likely good nutritional and energetic value. The appearance of the grazing marks varies between different herbivores and lichen species. Some herbivores eat through all the layers of the thallus without preferring preferring any particular parts (Fig. 3). Others graze only the upper parts, including the cortex and the photobiont layer (Fig. 2). Sometimes lichens are grazed from the underside where the fungal parts are situated. When the herbivore selects some parts of the thallus, it likely tries to avoid lichen compounds or seeks the most nutritious parts of the lichen. From some of the grazing marks it is possible to identify the grazer. Gastropods can be easy to identify if they leave marks from their mouth-parts called radula. Few potential lichenivores have also come along with some of the lichen samples (Fig. 4). Figure 1. Heavily grazed Lobaria. 49

51 VI. Lichen herbivory Figure 2. The upper cortex and the underlying photobiont layer have been eaten from the lichen Pseudochyphellaria. Also apothecia are grazed. Yellow medulla with lichen compounds is left untouched. Figure 3. Grazing marks on Sticta. Herbivore grazes through all layers and does not prefer any particular parts of the thallus. Also few little radula marks left by some gastropod. Figure 4. A potential lichenivorous gastropod and grazing marks on Leptogium. 50

52 VI. Lichen herbivory Conclusions Experiments have shown that some lichen secondary compounds can protect lichens against herbivores across taxonomic groups as gastropods, insects and mammals (Nybakken et al. 2010). On the other hand, sometimes herbivore pressure can be so high that it partly determines lichens distribution and can even enhance the disappearance of some species (Asplund, Larsson, Vatne & Gauslaa 2010). There have also been suggestions that some gastropods might benefit from ingesting lichen compounds. Other lichen compounds stay in the snails` bodies and could possible act as deterrents towards the snails and could possible act as deterrents towards predators (Hesbacher et al. 1995). Furthermore, lichens can be very important food source for some animals. For example, the highly endangered snub-nosed monkeys of China rely on lichens especially in winter times. The most preferred lichen species are very sensitive to air pollution what can be a major risk for the future of the monkeys (Grueter 2009). References Asplund, J., Larsson, P., Vatne, S. & Gauslaa, Y. (2010). Gastropod grazing shapes the vertical distribution of epiphytic lichens in forest canopies. Journal of Ecology 98: Asplund, J., Solhaug, K. A. & Gauslaa, Y. (2010). Optimal defence: snails avoid reproductive parts of the lichen Lobaria scrobiculata due to internal defence allocation. Ecology 91: 10, Gauslaa, Y. (2005). Lichen palatability depends on investments in herbivore defence. Oecologia 143: Grueter, C. C. (2009). Fallback foods of temperate-living primates: a case study on snubnosed monkeys. American Journal of Physical Anthropology 140: Hesbacher, S., Baur, B., Baur, A. & Proksch, P. (1995). Sequestration of lichen compounds by three species of terrestrial snails. Journal of Chemical Ecology 21: 2, Nybakken, L., Helmersen, A-M., Gauslaa, Y. & Selås, V. (2010). Lichen compoundsrestrain lichen feeding by bank voles (Myodes glareolus). Journal of Chemical Ecology 36:

53 52 VI. Lichen herbivory

54 VII. The lichen genus Coccocarpia in Taita Hills, Kenya VII. The lichen genus Coccocarpia in Taita Hills, Kenya Kaisa Jauhiainen Abstract Species of the pantropical cyanolichen genus Coccocarpia live in moist montane forests around the world. However, the number of species and their distributions are still quite insufficiently known. We have collected a total of 52 Coccocarpia specimens from different forests in the Taita Hills and Mt. Kasigau in Kenya. This material seems to include six different species of which two have not previously been reported from the region. Most of the specimens are from Mt. Kasigau, which has suffered less from human influence than the other moist forests in the region. Introduction The lichen genus Coccocarpia Pers. belongs to the family Coccocarpiaceae Henssen. It was first recognized by Persoon in By the end of 19th century, most of the currently recognized taxa in Coccocarpia had already been described. However, also during the 20th century a few new species were added to the genus. The comprehensive work in the taxonomy of Coccocarpia was done by Aino Henssen (1963), who after detailed investigations of the ascocarps, separated Coccocarpia from the Pannariaceae. In 1982 Arviddson published a worldwide monograph of Coccocarpia and recognized 21 species. Since then only a couple of new species have been described (Lücking et al. 2007; Marcano et al. 1995) totaling to the 27 species known today. The currently accepted systematic position of Coccocarpia is as follows: Kingdom: Fungi Division: Ascomycota Subdivision: Pezizomycotina Class: Lecanoromycetes Subclass: Lecanoromycetideae Order: Peltigerales W. Watson Suborder: Collematineae Miadlikowska & Lutzoni Family: Coccocarpiaceae (Mont. ex Mull. Stuttg.) Henssen Genus: Coccocarpia Pers. The genus Coccocarpia has a pantropical distribution with diversity centers in South America and Southeast Asia. Most species live in warm and humid areas, and seem to distinctly avoid dry regions. Three widely distributed species (Coccocarpia erythroxyli, Coccocarpia palmicola and Coccocarpia pellita) occur in North and South America, Africa, Asia, Australia and the Pacific. Two of these (Coccocarpia erythroxyli and Coccocarpia palmicola) have also been found in Alaska and Siberia a distribution pattern that is rather difficult to explain. Although thousands of Coccocarpia specimens were already mapped by Arvidsson (1982), the more detailed distributions of most species are still poorly known, especially in Africa. In their Macrolicens of East Africa Swinscow and Krog (1988) record seven Coccocarpia species: Coccocarpia adnata, Coccocarpia dissecta, Coccocarpia erythroxyli, Coccocarpia flavicans, Coccocarpia palmicola, Coccocarpia pellita and Coccocarpia stellata. Their 53

55 VII. The lichen genus Coccocarpia in Taita Hills, Kenya survey was based on a large collection of lichens from Ethiopia, Kenya, Tanzania and Uganda. A more recent checklist of lichens and lichenicolous fungi in Kenya (Feuerer 2010) includes the same seven species. As only one additional species (Coccocarpia myriocarpa) has since been reported from Tanzania, the total number of Coccocarpia species from East Africa is currently eight. Morphology and anatomy All Coccocarpia species found in the Taita Hills have a distinctly foliose, lobate thallus. Thalli of Coccocarpia are small to medium-sized, up to 15 cm in diameter, usually orbicular and firmly attached to the substrate by rhizines. The lobes are always dorsivental but there is marked variation in the shape and size of the lobes. The lobes provide many characteristics of potential taxonomic value, but one must be careful of using these to separate species, as they are variable and easily modified by climatic conditions and substrate (Arviddson 1982). The lobes of Coccocarpia are usually lead-grey or bluish-grey when dry, but also a diverse range of colors from whitish-grey, brownish, purplish, bluish-green to black can occasionally be seen. Additionally, wet lobes are darker in color than dry, and very often central parts of the thallus are lighter in color than lobe apices. The upper surface is smooth, but some transverse concentric ridges exist especially in larger species like Coccocarpia erythroxyli. The lower surface is matt or slightly shining and rhizinate. All rhizines are basically simple and they can vary in number from being sparse to numerous and in color from white to black. However, this variation does not seem to be of taxonomic importance (Arvidsson 1982). In narrowlobed species the rhizines are irregularly scattered, while in larger-lobed species they are mostly arranged in transverse concentric lines causing ridges to the upper surface. All Coccocarpia species in the Taita Hills have heteromerous thalli consisting of an upper cortex, an algal layer, a medulla and a lower cortex (Fig.1D). The upper cortex consists of one to three layers of parallel and periclinical hyphae running lengthwise in the lobes which are colorless in all species excluding Coccocarpia flavicans and Coccocarpia xanthorioides (Arvidsson 1982). The characteristics of the algal layer vary for each species and even within a single thallus. Hyphae in the algal layer are narrow and richly branched. Direct contacts between the photobiont and the mycobiont are not visible, although hyphae run often very close to the outer surface of the algal cells. The photobiont either forms irregular cluster of cells or a series of unbranched filaments (Fig.1B). The sizes of the individual cell in the photobiont remains fairly constant being 6 14 cm in diameter. The medulla consists of densely packed, conglutinate, horizontally aligned and parallel hyphae, which are arranged lengthwise in the lobes. Hyphae in the medulla are narrow with rectangular long cells. The thickness of the medulla is very variable ranging from 8 to100 m. The lower cortex is composed of one to three layers of periclinal, parallel hyphae running lengthwise in the lobes. The hyphae in the lower cortex are wider and the individual cells are shorter and have thicker walls than those of the medulla. Also the lower cortex hyphae are more closely joined to form a paraplectenchyma (Arvidsson 1982). Coccocarpia species are capable of vegetative and sexual reproduction. Vegetative reproduction is mainly by isidia, which are outgrowths of the thallus consisting of fungal hyphae and algal cells (Fig. 1C). Isidia are found in several species of Coccocarpia, and their presence and shape has been used to separate taxa at species level (Arvidsson 1982). The shape of isidia is usually either more or less cylindrical or flattened. The cylindrical isidia range from mm in diameter and they are usually laminal. 54

56 VII. The lichen genus Coccocarpia in Taita Hills, Kenya A B C D E F Fig. 1. Morphology and anatomy of Coccocarpia. A. Thallus lobes of Coccocarpia palmicola. Note the laminal isidia and an apothecium (upper right). B. Section of Coccocarpia thallus showing extensive algal layer and a group of rhizines (lower left). C. Thallus anatomy of Coccocarpia palmicola. Note the scale-like isidium (upper right). D. Section of Coccocarpia thallus showing the upper cortex, the algal layer, the medulla, the lower cortex and rhizines (from top to bottom). E. Section of Coccocarpia palmicola with apothecium. F. Cross section through hymenium of Coccocarpia erythroxyli. Note the three asci with fusiform spores. Isidia can vary in number from being sparse to numerous and in shape from being simple to branched, and these attributes can even vary within the same thallus. Flattened isidia are small, scale-like and grow either vertically or horizontally. They may resemble accessory lobules, which also are outgrowths of the thallus, but which show dorsiventral differentiation and eventually produce rhizines on their lower surface. 55

57 VII. The lichen genus Coccocarpia in Taita Hills, Kenya Fertile specimens of Coccocarpia produce apothecia on the upper surface. While the isidiate species are rarely fertile (Arvidsson 1982), we have found some fertile specimens from the Taita Hills (Fig. 1A). The apothecia of Coccocarpia species vary considerably in size, shape and color, and this variation is thought to mainly correlate with climatic conditions (Arvidsson 1982). The apothecia are laminal, scattered and orbicular when young, usually becoming more irregular with age (Fig.1E). Their color can vary from pale yellow to black, but this variation does not seem to be taxonomically important. The asci and paraphyses form a hymenium, the thickness of which varies between species. There are usually eight ascospores in each ascus. The spores are non-septate and hyaline, spherical, narrowly ellipsoidal or fusiform, thin-walled and often with two oil drops (Fig.1 F). In addition to apothecia, also pycnidia are produced. They tend to be frequent in species that are commonly fertile and sparse in the isidiate taxa (Arvidsson 1982). The pycnidia are rounded or bottleshaped and produce small, unicellular conidia (pycnospores). Preliminary observations from Taita Hills and Mt. Kasigau Professor Jouko Rikkinen, the author and other students have collected cyanolichens in Kenya in 2009, 2010 and Their collections include a total of 52 Coccocarpia specimens from different forests in the Taita Hills and Mt. Kasigau. The majority of specimens have been collected from Mt. Kasigau (32), but some specimens have also been found from other remnant forests, namely from Mwachora (2), Fururu (1), Chawia (4), Vuria (7) and Mbololo (1). In addition, a few specimens were collected from a small stand of indigenous trees at the summit of Shomoto Hill (5) near the TAITA Research Station. The identification of the specimens is still in process but we have tentatively identified five species: Coccocarpia erythroxyli, Coccocarpia flavicans, Coccocarpia palmicola, Coccocarpia pellita, Coccocarpia rottleri and one taxon (Coccocarpia sp.), which may represent an undescribed species. Table 1. The number of Coccocarpia specimens collected from different forests in the Taita Hills and Mt. Kasigau. Fururu Chawia Mbololo Mt. Kasigau Mwachora Vuria Shomoto Hill Coccocarpia erythroxyli 6 7 Coccocarpia flavicans 6 Coccocarpia palmicola Coccocarpia pellita Coccocarpia rottleri 2 Coccocarpia sp. 1 6 Further investigations on thallus anatomy and DNA work will probably help to elucidate the species identity of the unidentified taxon. As pointed out by Arvidsson (1982), the morphology of a Coccocarpia species often shows considerable variation due to different habitat variables. Also environmental factors might thus explain some unique features observed in the unidentified taxon. One should point out that the taxon in question is not the same lichen illustrated in Rikkinen (2010, Fig. 2A) and then tentatively identified as a Coccocarpia species in closer analysis that lichen turned out to be a Pannaria species (cf. Pannaria fulvescens (Mont.) Nyl.). 56

58 VII. The lichen genus Coccocarpia in Taita Hills, Kenya Indigenous moist montane forests provide favorable habitats for many tropical cyanolichens and Coccocarpia species are no exception (Arvidsson 1982). Such forests provide many shady and moist environments, where Coccocarpia species can be found growing on tree trunks among epiphytic bryophytes. Tree bark is the primary substrate to most of Coccocarpia, but they can also grow on rocks, leaves, on top of other lichens and in some cases even among mosses on the ground (Arvidsson 1982). Several lines of evidence indicate that the primary habitat of many Coccocarpia species may actually be in the well illuminated higher canopy of mature forests and thus sampling on shady forest floor cannot give a full picture of their overall distribution and abundance. With the exception of Mt. Kasigau, all Coccocarpia species in the Taita Hills region seem to be relatively rare. This may reflect the overall loss and fragmentation of the moist montane forests in the region. The area of indigenous forests in the Taita Hills has diminished approximately 98% over the last 200 years, mainly due to the deforestation of the land for agricultural purposes (Mwang ombe 2005). The relatively high number of Coccocarpia species in Mt. Kasigau may be partly explained by the remoteness the relatively large forest on Mt. Kasigau has managed to maintain its biological diversity better than smaller forest fragments in the Taita Hills. On the other hand, many Coccocarpia specimens in Mt. Kasigau were found in dry montane forests at relatively low elevations. So, the local distributions and habitat preferences of the different Coccocarpia species remain far from clear. Remarkably, our material includes several fertile specimens of isidate Coccocarpia species. As already mentioned, fertile specimens of isidiate species are usually rare (Arvidsson 1982). For example, the numerous lichens analyzed by Wang and coworkers from South Korea (2007) and Oksanen from China (2008) did not include any fertile specimens of isidiate species. Wang et al. (2007) even suggested that the presence or absence of apothecia could be used as a taxonomic character in the genus. However, a similar lack of apothecia in isidiate species is not evident in our material from the Taita Hills. We have found apothecia or apothecial initials in several isidiate species: in four specimens each of Coccocarpia palmicola and Coccocarpia sp., in three specimens of Coccocarpia flavicans and in one specimen of Coccocarpia pellita. Apothecia are also present in eight Coccocarpia erythroxyli specimens, this species being non-isidiate and more commonly fertile. Our new findings may indicate that Coccocarpia populations in different tropical regions rely on different forms of reproduction. Such differences might naturally have important implications for genetic diversity and rates of evolution. The photosynthetic partners in the lichen symbiosis can be a green alga and/or a cyanobacteria. The latter are also capable of nitrogen fixation in addition to photosynthesis. The taxonomy of cyanobacterial lichen photobionts and their free-living counterparts was traditionally based on morphological characters, as well as details in cell anatomy and cell division. For a long time it was thought that the cyanobacterial photobionts in Coccocarpia would belong to the genus Scytonema (Arviddson 1982), but recently this has been challenged by the findings of Lücking and coworkers (2009). Based on DNA studies, they found that the lichenized photobionts of Coccocarpia actually belong to a novel, previously unrecognized cyanobacterial lineage they named Rhizonema. Our upcoming analysis of the cyanobacterial photobionts of Coccocarpia species from the Taita Hills will undoubtedly shed more light into this interesting question. 57

59 VII. The lichen genus Coccocarpia in Taita Hills, Kenya References Arviddson, L. (1982). A monograph of the lichen genus Coccocarpia. Opera Botanica 67, Feuerer, T. (2010). Checklist of lichens and lichenicolous fungi of Kenya < Read Henssen, A (1963). Eine Revision der Flechtenfamilien Lichinaceae und Ephebaceae. Symbolae Botanicae Upsalienses 18, Lüking, R., A. Aptroot, J. L. Chaves, H. J. Sipman & L. Umana (2007). A first assessment of the TICOLICHEN biodiversity inventory in Costa Rica: The genus Coccocarpia (Peltigerales: Coccocarpiaceae). Bibliotheca lichenologica 95, Lüking, R., J. D. Lawrey, M. Sikaroodi, P. M. Gillevet, J. Luis Chaves, H. J. M. Sipman & F. Bungartz (2009). Do lichens domesticate photobionts like farmers domesticate crops? Evidence from a previously unrecognized lineage of filamentous cyanobacteria. American journal of Botany 96, Marcano, V. & A. Morales Mendez (1995). El genero Coccocarpia Pers. (Ascomicetes liquenizados) en Venezuela. Tropical bryology 10, Mwang ombe, J. (2005). Restoration and Increase of Forest Connectivity in Taita Hills: Survey and suitability assessment of exotic plantations for restoration. Project Report 13 pp. 0 Oksanen, M. (2008). Coccocarpia-suku Hunanin maakunnassa, Kiinassa. Unpublished Master's thesis 71 pp. Department of Biological and Environmental Sciences, University of Helsinki. Rikkinen, J. (2010). Cyanolichens of the Taita Hills and Mt. Kasigau. In: Johansson, T., Pellikka, P. & Sorvali, J. (eds.) Safari Njema an interdisciplinary field expedition to South- East Kenya. Expedition Reports of Department of Geography 46, University of Helsinki. Swinscow, T.D.V. & H. Krog (1988). Macrolichens of East Africa. 390 pp. British Museum (Natural History), London. Wang, X. Y., X. L. Wei, K. S. Han, Y. J. Koh & J. Hur (2007). Taxonomic study on the lichen genus Coccocarpia (Lecanorales, Ascomycota) in South Korea. Mycobiology 35,

60 VIII. Cyanobionts of some Lobaria, Pseudocyphellaria and Sticta species in Taita Hills, Kenya VIII. Cyanobionts of some Lobaria, Pseudocyphellaria and Sticta species in Taita Hills, Kenya Ulla Kaasalainen Introduction to cyanolichens Lichens are symbiotic associations between a fungus (mycobiont) and a photosynthetic partner (photobiont) which may be a green alga or cyanobacterium (cyanobiont). It is estimated that 13% of all lichen species have cyanobacterial symbionts, and the most common cyanobacterial genus in lichen symbioses is Nostoc (Rikkinen 2002). Several studies on cyanolichens have shown that mycobionts differ in cyanobiont selection (Paulsrud et al. 1998, 2000; Rikkinen et al. 2002; Lohtander et al. 2003; Myllys et al. 2007; Elvebakk et al. 2008, Fedrowitz et al. 2011). Some of the fungal species associate with only a small number of cyanobacterial strains while other are more promiscuous, and the identity of the cyanobiont strain seems to be determined by the fungal species rather than geographical origin of the specimen. This study examines cyanobiont selectivity in several species of Lobaria, Pseudocyphellaria, and Sticta collected from nine different forest patches in Taita Hills, Kenya. trna Leu (UUA) intron Our current genetic marker, the trna Leu (UAA) intron, has been successfully used in many cyanolichen studies (e.g. Paulsrud et al. 1998, 2000; Costa et al. 2002; Summerfield and Eaton-Rye 2006, Fedrowitz et al. 2011). Most of the sequence variation in the intron is confined to certain regions. For example the hypervariable P6b region consists of heptanucleotide repeats, which can be of type Class 1 or Class 2. In both cases, the repeats form the stems in the secondary structure, separated by not pairing loops. The length of the P6b region can also vary because of insertions and deletions (indels) of single or multiple heptanucleotide repeats or insertion of other elements not corresponding to the heptanucleotide repeat motif (Paulsrud and Lindblad 1998; Costa et al. 2002). In this study all the lichen species analysed have Nostoc cyanobionts with a Class 1 repeat motif in their P6b region. Materials and Methods Lichen specimens were collected from nine fragments of indigenous montane forest in Taita Hills: Chawia, Kasigau, Macha, Mbololo, Mwachora, Ngangao, Shomoto Hill, Vuria, and Yale. The lichens specimens discussed here have been preliminarily identified as Lobaria retigera, Pseudocyphellaria crocata, Sticta fuliginosa, S. limbata, S. sublimbata, and S. weigelii. Also two Leptogium cyanescens and two Sticta dichotoma specimens were found to house identical or very closely related Nostoc genotypes and were thus included in the data set. The DNA extraction, PCR, sequencing, sequence editing, and aligning of the trna Leu intron sequences were performed as described in Fedrowitz et al The trna Leu intron haplotype network was compiled with Network (Bandelt et al. 1999) and edited with CorelDrawX4. 59

61 VIII. Cyanobionts of some Lobaria, Pseudocyphellaria and Sticta species in Taita Hills, Kenya Cyanobionts of some Lobaria, Pseudocyphellaria and Sticta species in Taita Hills, Kenya 112 trna Leu (UUA) intron sequences represented 19 different haplotypes (Figure 1). The longest sequence was 416 bp and the shortest 337 bp, and most of the length variation was due to differences in the P6b-region. According to our data, Pseudocyphellaria crocata associates with some unique Nostoc haplotypes that are not found in any other cyanolichen species in the montane forests of Taita Hills. They show high sequence similarity and are distinguished from many other Nostoc haplotypes in having a long unique indel in the P6b region. Also Lobaria retigera appears to be quite selective with only two highly similar genotypes being detected from this lichen species. However, in contrast to the situation observed in P. crocata, L. retigera shares the more common cyanobiont haplotype with several species of Sticta. All the other lichen species dealt with here, i.e. Leptogium cyanescens, Sticta dichotoma, S. fuliginosa, S. limbata, S. sublimbata, and S. weigelii share a variable selection of different Class 1 type trna Leu intron haplotypes. No spatial trends are obvious in the distribution of specific trna Leu intron haplotypes: haplotypes acquired from lichen specimens collected from different forests occur in different parts of the haplotype network and many haplotypes were present in several different forest fragments. In summary and in good congruence with the results of previous studies on the symbiont specificity of cyanolichens, the identity of the Nostoc cyanobiont is not site dependent, but is more determined by the species identity of the lichen mycobiont. Some mycobiont species depend on their own Nostoc haplotypes, while others seem to exploit a common pool of appropriate cyanobionts. In other words, the mycobionts of tropical cyanolichens in the Taita Hills differ in their cyanobiont utilizing strategies. 60

62 VIII. Cyanobionts of some Lobaria, Pseudocyphellaria and Sticta species in Taita Hills, Kenya Figure 1. Haplotype network compiled from trna Leu (UUA) intron of the lichen cyanobionts collected from Taita Hills. Inside each box are the specimens from which the same trna Leu haplotype was acquired. The collection location and the number of specimens (in parenthesis) are mentioned after the species. The number of nucleotide differences is shown next to each connecting line. The bold line shows the places of the longer indels.

63 VIII. Cyanobionts of some Lobaria, Pseudocyphellaria and Sticta species in Taita Hills, Kenya Acknowledgements Great thanks to Jouko Rikkinen for the collection and identification of the lichen samples and Rachel Strickman for help with the lab work. References Bandelt H-J, Forster P, Röhl A (1999) Median-joining networks for inferring intraspecific phylogenies. Mol Biol Evol 16:37-48 Costa JL, Paulsrud P, Lindblad P 2002: The cyanobacterial trna Leu (UUA) intron: Evolutionary patterns in a genetic marker. Molecular Biology and Evolution 19: Elvebakk A, Papaefthimiou D, Robertsen EH, Liaimer A 2008: Phylogenetic patterns among Nostoc cyanobionts within bi- and tripartite lichens of the genus Pannaria. Journal of Phycology 44: Fedrowitz, K., Kaasalainen, U. & Rikkinen, J. 2011: Genotype variability of Nostoc symbionts in three epiphytic Nephroma species in a boreal forest landscape. The Bryologist 114: Lohtander K, Oksanen I, Rikkinen J 2003: Genetic diversity of green algal and cyanobacterial photobionts in Nephroma (Peltigerales). Lichenologist, 35: Myllys L, Stenroos S, Thell A, Kuusinen M High cyanobiont selectivity of epiphytic lichens in old growth boreal forest of Finland. New Phytologist 173: Paulsrud P and Lindblad P 1998: Sequence variation of the trnaleu intron as a marker for genetic diversity and specificity of symbiotic cyanobacteria in some lichens. Appl. Environm. Microb. 64: Paulsrud P, Rikkinen J, Lindblad P 1998: Cyanobiont specifity in some Nostoccontaining lichens and in a Peltigera aphthosa photosymbiodeme. New Phytologist 139: Paulsrud P, Rikkinen J, Lindblad P Spatial patterns of photobiont diversity in some Nostoc-containing lichens. New Phytologist 146: Rikkinen, J Cyanolichens: An evolutionary overview. Pages in: Cyanobacteria in Symbiosis. A. N. Rai, B. Bergman, and U. Rasmussen, eds. Kluwer Academic Publisher, Dordrecht, The Netherlands. Rikkinen J, Oksanen I, Lohtander K Lichen guilds share related cyanobacterial symbionts. Science 297:357. Summerfield TC and Eaton-Rye JJ 2006: Pseudocyphellaria crocata, P. neglecta and P. perpetua from the Northern and Southern Hemispheres are a phylogenetic species and share cyanobionts. New Phytologist 170:

64 IX. Newtonia buchananii and wood-rotting Phellinus species in the Taita Hills IX. Newtonia buchananii and wood-rotting Phellinus species in the Taita Hills Anna Norberg Abstract Newtonia buchananii (Baker) G. Gilbert & Boutique is one indigenous tree species in the montane forests of the Taita Hills. According to studies in the Usambara Mountains, Tanzania, several species of wood-decaying fungi of the genus Phellinus grow on N. buchananii. One species was also identified from the Taita Hills and identified as Phellinus gilvus. Excessive human influence and fungal pathogens may pose a serious threat to the indigenous N. buchananii in Taita forests. Introduction Newtonia buchananii (Baker) G. Gilbert & Boutique is one of the many indigenous tree species found in the Taita Hills, Kenya. The species prefers moist montane forests with an intact canopy (Redhead 1981), like the remaining mist forests in the Taita Hills. Unfortunately Taita forests have been severely fragmented and large areas have been cleared for agriculture, charcoal production and firewood collection (Beentje,1988; Collins and Clifton 1984). Exotic plantation forests of pine (Pinus spp.), cypress (Cupressus lusitanica) and eucalyptus (Eucalyptus sp.) have not really helped to preserve many of the indigenous forest species in the Taita Hills. Plantation forests, which were mainly planted in the 1960s 1980s, were established to encourage softwood production, to protect the remaining indigenous forest, and also to decrease soil erosion (Rogo & Oguge 2000). Unfortunately many of these goals were not achieved, and due to growing land use pressures and lack of enforcement, human disturbance of indigenous forests has continued or even increased. Thus, the species compositions of many Taita forests have experienced notable changes (Omoro et al. 2010). Human influence has also reduced the prevalence of N. buchananii, which is a tree species strongly dependent on growth conditions prevailing in natural forests. What are not as self-evident are the various effects on other species, such as epiphytic plants and wood-rotting fungi which live on this particular tree species. For example, there seem to be no published records of the fungi that grow on N. buchananii in the Taita Hills. However, Niemelä and Mrema (2002) have examined the polypore fungi (decay-causing poroid Basidiomycetes) of N. buchananii in the Usambara Mountains, Tanzania. The Usambara Mountains are located roughly 150 km southwest of the Taita Hills. Both are part of the Eastern Arc mountain chain. 63

65 IX. Newtonia buchananii and wood-rotting Phellinus species in the Taita Hills During the field course in January 2011, I examined the diversity of polyporous fungi in the Taita Hills and found an interesting Phellinus species growing on a massive individual of Newtonia buchananii the Mother Tree of the Ngangao forest. Some Phellinus species from East Africa Phellinus newtoniae Niemelä & Mrema Phellinus newtoniae is a large, 10 to 25 cm wide, perennial polypore (Niemelä & Mrema 2002). The basidiocarp surface is variably dark brown coloured. The pore surface is cinnamon brown with round, unevenly distributed and small pores, (5) 6 8 per mm. The colour of the context varies from golden yellow in young fruit bodies to cinnamon brown in old ones. P. newtoniae has a dimitic hyphal system and the septa do not have clamp connections. There are no cystidia or setae. The basidiospores are subglobose, (4.8) (6.3) x (4.4) (5.8) µm, thick-walled, pale brown in CB, yellow-brown in IKI, red-brown in KOH and young, still hyaline spores are also CB+ (Niemelä & Mrema 2002) This species was recently described by Niemelä & Mrema from the Mazumbai Forest Reserve in the West Usambara Mountains. The holotype was collected from living N. buchananii. While the species seems to grow mainly on N. buchananii, there is also one record from Agarista (Agauria) salicifolia (Niemelä & Mrema 2002). Phellinus cf. rimosus (Berk.) Pilát Phellinus cf. rimosus is a perennial, pileate and solitary polypore (Ryvarden & Johansen 1980). The pileus is umbonate, smooth and golden yellow when young, but thick, triquetrous, up to 20 cm wide and greyish brown when old (Niemelä & Mrema 2002). The fruit body first remains non-poroid for many years, but after developing, the pore surface of the fungus is a bit darker than the edge and there are 6 to 8 pores per mm. The context is usually very thick and yellow- to brass-brown. Phellinus cf. rimosus grows on various hosts and is widespread in Europe, Africa, Asia and Australia (Ryvarden & Johansen 1980). The young stage of the polypore was described for the first time by Niemelä & Mrema (2002).The hyphal system of the fungus is dimitic and without clamp connections. There are no cystidia nor setae present. Basidiospores are subglobose, brown, (5.1) (6.2) x (4.4) (5.6) µm with thick walls, CB-, yellow-brown in IKI and red-brown in KOH. Phellinus fastuosus (Lév.) Ryvarden The basidiocarps of Phellinus fastuosus are perennial and solitary or slightly imbricate (Ryvarden & Johansen 1980). The shelf-shaped or triquetrous, up to 18 cm wide pilei are cigar brown, with a sepia or black-brown upper surface (Niemelä & Mrema 2002). The pore surface and context layer are both dark cinnamon brown. The context is thin compared to the tube layer and there is a visible crust. The pores are round and there are 6 to 8 pores per mm. The hyphal system is dimitic and without clamp connections (Niemelä & Mrema 2002). No cystidia nor setae are present and the basidiospores are subglobose and brown, (4.9 ) ( 6.1) x (4.4 )

66 IX. Newtonia buchananii and wood-rotting Phellinus species in the Taita Hills (5.4) µm. The walls of mature spores are thick and CB-, although when very young the spores are hyaline and CB+. Phellinus fastuosus is a pantropical species and seems to be rather common in East- Africa (Ryvarden & Johansen 1980). Phellinus callimorphus (Lév.) Ryvarden Phellinus callimorphus is perennial, thin, flat and conchate (Niemelä & Mrema 2002). The pileus is usually less than 1 cm thick and up to 7 cm wide and 10 cm long (Ryvarden & Johansen 1980). The upper surface of the basidiocarp is cigare brown and there is a clear sterile margin at the edge, distinct from the underside (Niemelä & Mrema 2002). The pore surface is dark umber brown and pores round, 8 to 10 per mm. The context is soft and homogenous, cinnamon or clay buff. The hyphal system of P. callimorphus is dimitic and there are some crystal-bearing hyphae present at tube mouths (Niemelä & Mrema 2002). Hymenial setae are often abundant (Ryvarden & Johansen 1980). The setae are brown, acuminate, thick-walled, often with a swollen belly, (21 ) ( 33) x (5 ) ( 8) µm (Niemelä & Mrema 2002). The basidiospores are ellipsoid, thin-walled, hyaline, often with the apiculus arising closer to the ventral side, (3.3 ) ( 4.5) x ( 3.3) µm, IKI- and CB-. Phellinus callimorphus is a common species with a wide host range: it grows on indigenous broadleaved trees and also on exotic angio- and gymnosperm trees (Niemelä & Mrema 2002). There are collections from Madagascar, Rwanda (Ryvarden & Johansen 1980) and Tanzania (Niemelä & Mrema 2002). Phellinus gilvus (Schwein. : Fr.) Pat. Phellinus gilvus is an annual or short-lived perennial of some years (Niemelä & Mrema 2002). The pilei are shelf-shaped and up to 9 cm wide. The colour of the upper surface varies from pale brown to cinnamon or dark brown. The colour of the pore surface is similar or a bit darker than that of the upper surface. There are 9 to 11 pores per mm. The context is thin, cinnamon coloured and corky soft. The hyphal system is dimitic and crystal-bearing hyphae occur often, but not always, at tube mouths (Niemelä & Mrema 2002). Hymenial setae are brown, pointy and narrow, (17) ( 30) x 4 6 (7) µm. Basidiospores are ellipsoid, (3) (4.7) x (2.1) (3.1) µm, thin-walled and hyaline. Phellinus gilvus grows on angiosperms (Ryvarden & Johansen 1980), mainly on dead tree trunks, stumps and large fallen branches (Niemelä & Mrema 2002). This pantropical species is common in East-Africa and also found in the warmer parts of the temperate zone (Ryvarden & Johansen 1980). Phellinus sublaevigatus (Cleland & Rodway) P. K. Buchanan & Ryvarden Phellinus sublaevigatus is a perennial species. The fruit bodies are resupinate and usually up to 1 cm thick, but sometimes up to 4 cm (Niemelä & Mrema 2002). When present the sterile upper surface is dark vinaceous or greyish brown, the pore surface is umber to clay buff, paler when not actively growing, and has 6 to 8 pores per mm. There are distinct annual layers in the context. The hyphal system is indistinctly 65

67 IX. Newtonia buchananii and wood-rotting Phellinus species in the Taita Hills dimitic (Niemelä & Mrema 2002). Brown, sharp-pointed and narrow hymenial setae, (14) (31) x (3.5) (7.5) µm, are abundant in some sections but almost absent in others. Basidiospores are subglobose, (5) (8.2) x (4.3) (7.4) µm, thick-walled, hyaline, strongly dextrinoid and CB+, often deteriorated. Phellinus sublaevigatus was reported from Africa by Niemelä and Mrema (2002). The species has also been found from Australia (Buchanan & Ryvarden 1993). Phellinus wahlbergii (Fr.) D. A. Reid Phellinus wahlbergii is a perennial species with shelf-shaped or triquetrous basidiocarps (Niemelä & Mrema 2002). The fungus can sometimes become very large with age, but typical basidiocarps are up to 8 cm wide. The upper surface is dark cinnamon, the ore surface slightly darker and with 5 to 7 pores per mm. The context is thin and corky soft, cinnamon coloured. The hyphal system is dimitic and crystalbearing hyphae are common at tube mouths (Niemelä & Mrema 2002). The redbrown hymenial setae are subulate or narrow ventricose with a sharp, straight or hooked apex. The setae are (29) (50) x (6) (11) µm. Basidiospores are subglobose, (3.8) (5.5) x (3.1) (4.2) µm, hyaline, IKI-, and slightly CB+. Phellinus wahlbergii grows on angiosperms in Africa, South-Eastern-Asia and Australia (Ryvarden & Johansen 1980). In East-Africa, it has been reported from at least from Kenya, Ethiopia (Ryvarden & Johansen 1980), and Tanzania (Niemelä & Mrema 2002). Methods Field inventory Fungal specimens were collected during excursions to the local forests in the Taita Hills. Previously marked sample plots in four forests (Ngangao, Vuria, Fururu and Chawia) were studied in some detail. As it was the dry season in the area and the forests were relatively dry, the fungal basidiocarps were not abundant. In order to obtain a moderate amount of specimens, also some fungi between sample plots were collected. Mature specimens of N. buchananii trees were scarce in the forests since the uppermost canopy layer was missing in many parts. However, some such trees were found and the fungi growing on them sampled. After the field excursions, the fungal specimens were dried in an Evermat dryer for one night. After returning to Finland, at the Botanical Museum of Helsinki University, the specimens were kept in a freezer (in approximately -18 C) for two weeks to avoid potential contamination of herbarium collections by insects and other invertebrates. Species identification African polypores have not been intensively studied. Accordingly, species identification is often difficult and uncertain at best it is probable that some of the 66

68 IX. Newtonia buchananii and wood-rotting Phellinus species in the Taita Hills species presently recognized will be eventually divided in several taxa, and the systematics of the fungi will change in other ways. It is revealing that the best guide to the polypore flora of East Africa is still A preliminary Polypore Flora of East Africa by Ryvarden and Johansen (1980). The book was published over 30 years ago and the authors already then underlined that the treatment should be taken as a preliminary edition. Another difficulty lies in the accurate identification of polypore substrates. It is challenging to determine the substrate on which the collected fungus grew since the substrate is often partly or almost completely decomposed. Even living trees are often challenging to identify since the canopy is often high and it is hard to see which leaves belong to which trunk. For this report, one Phellinus-species collected from an old living N. buchananii (known as the Mother Tree in Ngangao forest) was studied in order to identify one of the wood-decaying fungus species growing on N. buchananii in the Taita Hills, and also to get a feeling of the work load involved in identifying all the collected specimens from the area. The macrological traits features of the freshly collected fungus were written down from the fresh specimens immediately after it was collected and the microscopical analysis was done from the dry herbarium specimens at the Helsinki Botanical Museum with the help of docent Tuomo Niemelä. The species found on N. buchananii was Phellinus gilvus (Schwein. : Fr.) Pat. As already described, there is a level of uncertainty in the delimitation of this species from some closely related Africa taxa, including P. gilvus, P. callimorphus, and P. senex (Nees & Mont.) Imaz. Within P. gilvus there is some variation between different collections (Niemelä & Mrema 2002). Two groups have been tentatively identified: collections from the Mazumbai, West Usambara mountains, Tanzania, present a montane variety, which has shorter spores (L= µm) than the lowland variety, corresponding to the original description of the species. The spore width is the same in both varieties. As it is possible that P. gilvus is in fact a complex of sibling species, we determine the fungus as Phellinus gilvus (coll.). Obviously, the Phellinus species of Africa require a more extensive study with systematic sampling. Discussion Wood-rotting fungi and especially polypores, including Phellinus species, are the primary causes of living tree trunk degradation, i.e., butt- and heart-rot in living trees (Corner 1983, Masuka 1991, Mswaka 1991, Mrema & Nummelin 1998). All Phellinus species cause white-rot. In other words, the fungi produce cellulase and lignase and degrade all components of wood cell walls (Gilbertson 1981). Several studies have shown that stem cracks provide entry points for fungal pathogens resulting in infecting a living tree (Bostock & Stermer 1989). Even though studies also show that vegetative structures like basal sprouts and trunk injuries are capital 67

69 IX. Newtonia buchananii and wood-rotting Phellinus species in the Taita Hills causes of stem cracks in living trees (Butin & Shigo 1981), also drought stress is a crack triggering mechanism (Day 1954). According to Kramer (1983) the tree species with shallow root systems such as N. buchananii experience water deficiency more easily than trees with more deep-growing roots, and the water deficit may cause cracking in the trees. Mrema & Nummelin (1998) studied differences in stem cracking and ultimately the occurrence of pathogenic infection in N. buchananii in a forest reserve and in more disturbed forests. They found that the harsh dry periods experienced by trees in disturbed forests may have had an effect on the ability of pathogens to infect the living trees via stem injuries. Even though more studies in disturbance ecology are needed, the extensive rot in Newtonia buchananii seems to represent one threat to the montane forests in the West Usambara Mountains (Mrema & Nummelin 1998). As N. buchananii is a climax tree species the death of old individuals tend to create large gaps in the forest canopy (Mrema & Nummelin 1998). Because of extensive rot, the rate of gap formation may have accelerated beyond rates characteristic of healthy rain forests. In disturbed forest it is possible that N. buchananii is in a danger of local extinction. It is quite possible, that also the remaining N. buchananii trees in the forest of Taita Hills could suffer from the same problem involving environmentally induced stem cracks and fungal decay, which could seriously threaten the future of the species in the region. References Beentje, H. J. (1998). An ecological and floristical study of the forests of the Taita Hills, Kenya. Utafiti 1, Collins, M. & Clifton, M. (1984). Threatened wildlife in the Taita Hills. Swara 7, Corner, E. J. H. (1983). Ad Polyporaceas I. Beiheft Nova Hedwigia 75, Bostock, R. M. & Stermer (1989). Perspectives on wound healing resistance to pathogens. Annual Review of Pythopathology 27, Bryce, J. M. (1967). The commercial timbers of Tanzania. Tanzania Ministry of Agriculture and Co-operatives, Forest Division, Moshi. 173 s. Buchanan, Pk. K. & Ryvarden, L. (1993). Type studies in the Polyporaceae 24, species described by Cleland, Rodway and Cheel. Australian Systematic Botany 6, Butin, H. & Shigo, A. L. (1981). Radial shakes and frost cracks in living oak trees. USDA Forest Service, Northeastern Forest Experiment Station, Research Paper NE 478. Day, W. R. (1954). Drought cracks of conifers. Forestry Commission UK, Forest Record 26. Kramer, P. J. (1983). Water Relations of Plants. Academic Press, New York. Masuka, A. J. (1991). Aphyllophorales in pine and eucalypt plantations in Zimbabwe, their taxonomy and ecology. Thesis, University of Zimbabwe. Mrema, F. A. & Nummelin, M. (1998). Stem cracks and decay in Newtonia buchananii trees in the Mazumbai Forest Reserve, West Usambara Mountains, Tanzania. Journal of East African Natural History 87,

70 IX. Newtonia buchananii and wood-rotting Phellinus species in the Taita Hills Mswaka A. Y. (1991). A mycofloristic survey of the Polyporaceae s. lato of indigenous forest habitats in Zimbabwe. Thesis, University of Zimbabwe. Niemelä, T. & Mrema, F. A. (2002). Newtonia buchananii and its fungal decayers in natural stands. Karstenia 42, Omoro, L. M. A., Pellikka, P. K. E. & Rogers (2010). Tree species diversity, richness, and similarity between exotic and indigenous forests of Eaastern Arc Mountains, Taita Hills, Kenya. Journal of Forestry Research 21(3), Redhead, J. F. (1981). The Mazumbai forest, an island of lower montane rain forest in the West Usambaras. African Journal of Ecology 19, Rogo, L. & Oguge, N. (2000). The Taita Hills forest remnants: a disappearing world heritage. Ambio 29, Ryvarden, L & Johansen, I.. (1980). A preliminary polypore flora of East-Africa. Fungiflora, Oslo. 69

71 70 Matkapäiväkirjat travel diaries

72 Matkapäiväkirjat travel diaries TRAVEL DIARIES OF THE EXCURSION - MATKAPÄIVÄKIRJAT

73 Matkapäiväkirjat travel diaries Excursion ensimmäinen päivä, Nairobi Sunnuntai Pekka Itkonen Olimme saapuneet Tuuli Toivosen kanssa edellisenä iltana, lauantaina 15.1., Nairobiin, missä Jomo Kenyattan lentokentällä meitä vastassa oli paikallinen yhteistyökumppani Ken. Ken toivotti meidät tervetulleeksi maahansa ja kuljetti meidät autollaan Anglican Church of Kenya Guesthouseen, joka sijaitsee reilun kilometrin päässä ydinkeskustasta lounaaseen, Uhuru Parkin länsipuolella. Lentokentältä keskustaan johtava tie sivuaa paikoin Nairobin kansallispuistoa, joten jos olisimme olleet liikkeellä päiväsaikaan, eivät aidantakaiset kirahvihavainnot olisi olleet kuulemma lainkaan tavattomia. Saapuessamme ACK Guesthouseen olimme ainoat seurueemme jäsenet paikalla. Retken vastaavat professorit Petri Pellikka ja Jouko Rikkinen sekä Tino Johansson liittyisivät seuraamme sunnuntaina/maanantaina, jolloin suuntaisimme kohti Taitavuoria. Petri, Jouko ja Tino olivat viettäneet jo edeltävän viikon Wundanyissa sijaitsevan Taitavuorten tutkimusaseman avajaisjuhlallisuuksissa, asema kun oli siirtynyt hiljattain käytännössä Helsingin yliopiston alaisuuteen. Seurueen biologianopiskelijoiden oli määrä saapua sunnuntai-illan lennoilla, maantieteilijät Henri Riihimäki ja Reeta Airaksinen olivat matkailleet edellisviikon Kenian itärannikolla Mombasan seutuvilla ja saapuivat Nairobiin varhain sunnuntaiaamuna. Sunnuntain ohjelmaan osallistuivat siis maantieteen opiskelijat Henri Riihimäki, Reeta Airaksinen ja Pekka Itkonen sekä FT Tuuli Toivonen. Ajoneuvon kuljettajana ja paikallisolojen asiantuntijana toimi Mr. Ken. Aamiaisen jälkeen seurueemme suuntasi The David Sheldrick Wildlife Trustiin, elefanttien ja sarvikuonojen orpokotiin. Vierailuaikaan paikalla oli jo paljon kuulijoita, ja koska saavuimme hieman viime tingassa, osa esitelmöinnistä meni valitettavasti ohi korvien epäsuotuisan kuuntelupaikan vuoksi. David Sheldrickin säätiö on perustettu vuonna Toiminta keskittyy enimmäkseen yhteistyöhön Tsavon kansallispuiston kanssa, jonne elefantit ja sarvikuonot sijoitetaan niiden ollessa kyllin vanhoja ja vahvoja. Säätiö toimii myös aktiivisesti julkisessa keskustelussa ottaen kantaa luonnonsuojelun kiistanalaisiin puheenaiheisiin. Moni orpokotiin päätyneistä elefanteista on menettänyt emonsa salametsästäjien ampumana norsunluukaupan vuoksi. Eräs säätiön toiminnan keskeisistä kohdista onkin aktiivinen kampanjointi norsunluutuotteita vastaan. Nuori elefantti on hyvin riippuvainen emostaan ja tämän äidinmaidosta, joten orpokodissa elefantinpoikasia ruokitaan äidinmaidonkorvikkeella. Luonnossa elefanttiemot suojaavat poikasiaan liialta auringolta ja tallovat maata pehmittääkseen sopivan makuupaikan poikaselleen. Orpokodin työntekijät suojelevatkin pienimpiä aurinkovarjoin, levittelevät niiden päälle aurinkorasvaa ja asettelevat patjoja pikkuelefanteille makuualustoiksi. 72

74 Matkapäiväkirjat travel diaries Kuva 1. The David Sheldrick Wildlife Trustin työntekijät hoitavat orpoja elefantteja. Orpokodista siirryimme African Fund for Endangered Wildlife kansalaisjärjestön ylläpitämään Giraffe Centreen, jossa pääsimme näkemään läheltä hyvin uhanalaisia Rothschildin kirahveja, joita elää vain Itä-Afrikan savanneilla. Järjestön tavoitteena on suojella Rothschildin kirahveja, ja se onkin onnistunut toiminnassaan tuottamalla useita lisääntymiskykyisiä kirahvipariskuntia Kenian kansallispuistoihin. Giraffee Centerissä pääsimme syöttämään kirahveille ravintopellettejä käsistämme ja jopa suistamme. Kirahvit käyttävät syödessään kieltään taitavasti ja niiden sylki on antiseptistä, joten suuteleminen kirahvin kanssa ei ole niin sotkuista ja ällöttävää kuin luulisi. Juuri antiseptisen sylkensä vuoksi kirahvi on ainoa laji, joka pystyy käyttämään ravinnokseen akaasian lehtiä, sillä piikkien suuhun repimät haavat paranevat nopeasti syljen ansiosta. Kirahvin sydän painaa noin 11 kg, joka pumppaa verta erittäin kovalla paineella ympäri sen elimistöä. Tämän vuoksi kirahvit eivät voi nukkua pää alhaalla, sillä päähän kertynyt veri aiheuttaisi vakavia vaurioita. Kirahvit nukkuvatkin oppaan esitelmöinnin mukaan vain 5 30 minuuttia vuorokaudessa. Joskus seisaaltaan, joskus kontallaan, pää jatkuvasti ylhäällä. Pahimmat kirahvin luontaiset viholliset ovat hyeena ja leijona. Saalistajien on oltava kuitenkin tarkkana, sillä napakasti potkaistessaan kirahvi pystyy tappamaan aikuisen leijonan yhdellä iskulla. 73

75 Matkapäiväkirjat travel diaries Kuva 2. Rothschildin kirahvi Daisy syö pellettejä kädestä. Kuva 3. Vapaaehtoiset saivat jopa suudella Daisya. Luonnonsuojeluaiheisen päivän päätteeksi tutustuimme Nairobin kaupunkiin, johon saimme perspektiiviä tutkailemalla kaupunkirakennetta 105-metrisen, 30-kerroksisen 74

76 Matkapäiväkirjat travel diaries Kenyatta International Conference Centerin katolta. Kyseinen rakennus komeilee myös sadan shillingin setelissä. Katolta avautuivat upeat näkymät ympäri Nairobin, ja paljaallakin silmällä erotti selvästi muun muassa Nairobin kansallispuiston, Ngong Hillsin ja Afrikan suurimman slummin, Kiberan. Ken kävelytti meitä Nairobin ydinkeskustassa, jossa katukuvaa hallitsevat korkeat hallintorakennukset. Nairobi on tunnettu maineestaan yhtenä maailman vaarallisimmista kaupungeista, mutta viiden hengen seurueena liikkuminen päiväsaikaan kaupungin keskustassa ei missään vaiheessa vaikuttanut vähääkään vaaralliselta. Kuva 4. Henri, Ken, Reeta ja Tuuli Kenyatta International Conference Centerin edustalla Nairobissa. 75

77 Matkapäiväkirjat travel diaries Kellon tullessa puoli viisi Henri ja Reeta suuntasivat hotellille elpymään edellisyön matkastaan Mombasasta Nairobiin. Päätimme Tuulin kanssa vielä suunnata National Museum of Kenyaan, vaikka tiesimmekin, että visiittimme jää korkeintaan tunnin mittaiseksi. Useista mielenkiintoisista näyttelyistä mieleenpainuvimpia olivat nisäkäsnäyttely ja Turkanajärven fossiilit, etenkin maailmankuulu pystyihmisen fossiili Turkanan poika. Illan tullessa suuntasimme Tuulin kanssa taksilla takaisin hotellille, josta lähdimme piakkoin läheisen hotellin ravintolaan syömään illallista koko suomalaisseurueellamme. Retkeläisten lisäksi seurassamme illastivat Helsingin yliopiston evolutionäärisen paleontologian professori Mikael Fortelius ja Luonnontieteellisen keskusmuseon johtaja Leif Schulman. Biologian opiseklijoista tässä vaiheessa paikalla oli ainoastaan Petri Nyqvist, myöhemmin illalla hotellille saapuisivat heistä loputkin: Anna Norberg, Kaisa Jauhiainen, Anniina Mäkelä, Mervi Laitinen ja Ulla Kaasalainen. 76

78 Matkapäiväkirjat travel diaries Nairobista tutkimusasemalle Wundanyissa - Maanantai Anna Norberg Kenttäkurssin ensimmäinen varsinainen kurssipäivä alkoi Nairobissa aurinkoisena, ja innokkaat kurssilaiset heräilivät auringon noustessa kuuden jälkeen ehtiäkseen aamupalalle ennen lähtöä. Yö oli vietetty mukavasti hostellissa ja päivä tulisi kulumaan pitkälle autossa istuskellen määränpäänä Wundanyi ja kurssin tuleva tukikohta eli yliopiston kenttäasema. Lähtö viivästyi hieman, kun oppaamme Ken juuttui aamuruuhkaan matkallaan hostellille. Kahden kilometrin matkaan kului reilu puoli tuntia. Kenialainen ruuhka on omaa luokkaansa, ainakin näin suomalaisen silmin. Matkaan päästään lähtemään kello Seuraava hidastetta ei tarvitse kauaa odotella: seuraavan pysähdyksen yhteydessä huomataan, ettei aseman auton takakonttia saada takaisin kiinni. Lukossa on jotain vikaa. Aurinko paistaa kirkkaalta taivaalta ja alkaa tulla kuuma. Onneksi Ken on käytännön miehiä ja selvittää lukko-ongelman, ja matka jatkuu kohti bensa-asemaa ja tavaratalo Nakumatia. Ostosten jälkeen päästään vihdoin suuntaamaan ulos kaupungista ja aloittamaan varsinainen matkanteko kohti Wundanyita. Kaupungin slummiutuneilla laita-alueilla näemme alueen asukkaiden ja asumusten lisäksi muun muassa vuohia tien vierustoilla ja kuskin iloksi myös tietä ylittävän lammaslauman. Kuva 1. Nakumatista saimme mukaan tarbittavat matkaeväät. Muutakin olisi ollut kaupan. 77

79 Matkapäiväkirjat travel diaries Nairobista kaakkoon suuntaavaa tie on Kenian mittakaavassa erittäin hyväkuntoinen. Keltanokan silmin on ajokulttuuri melkoisen hurjan näköistä ja tuntuista: tiukkoja ohituksia, iloisen värisiä mutta isoja rekkkoja toinen toisensa jälkeen ja kuoppainen tie. Onneksi äiti ei ole näkemässä tätä. Professori Pellikka viihdyttää takapenkillä hikoilevia kurssilaisia opettamalla hieman kiswahilin perusteita. Ndio tarkoittaa kyllä, la tarkoittaa ei, asante on yhtä kuin kiitos ja karibu tervetuloa! Ajettuamme jonkin aikaa, alkaa ympärillä näkyä kaikenlaista jännittävää. Ensimmäiset kirahvit bongattiin kello 11:40 ja vain hetkeä myöhemmin strutsipari ja termiittipesät herättävät innostusta. Simban kylän kohdalla pysähdytään ostamaan pari tomaattipussia tien vieressä passissa olevilta vihannesmyyjiltä. Matkan aikana pysähdytään vielä pari kertaa hieman jaloittelemaan ja ehkä muutama matkamuistokin tarttui innokkaimmille jo mukaan taukopaikkojen matkamuistomyyjiltä. Paviaaneja ja seeproja saadaan ihailla aivan tien vieressä ja kohta näkyy horisontissa jo Taitavuoret. Päämäärä lähestyy! Ennen Wundanyihin menoa käydään vielä kääntymässä Voin kaupungissa, joka on asemaan nähden lähin kaupunki. Sitten nokka kohti länttä ja ajelemaan viimeiset kilometrit kuoppaista tietä pitkin kohti asemaa. Vihdoin perillä! Hämärän alkaessa jo kohta laskeutua ovat kaikki autot päässeet turvallisesti aseman pihalle parkkiin. Vastassa on aseman henkilökuntaa: Granton ja Mwadime, jotka toivottavat koko porukan sydämellisesti tervetulleeksi. Huoneisiin asettumisen jälkeen on illallisen aika ja tulevien päivien ohjelman läpikäynti. Pitkän, kuuman ja uuvuttavan päivän jälkeen kurssilaiset ovat valmiita menemään ajoissa nukkumaan, eikä Afrikan pilkkopimeä yö kirkkaine tähtitaivaineen vaikeuta unen saantia laisinkaan aseman mukavissa sängyissä. 78

80 Matkapäiväkirjat travel diaries Ngagaon metsässä - Tiistai Reeta Airaksinen Hyvin levätyn yön jäljiltä aamu kuuden herätys ei tuntunut liian pahalta. Ensimmäinen kokonainen päivä tutkimusasemalla on käsillä ja tunnelma aamupalalla on innostunut. Ensimmäinen metsäpäivä oli tarkoitus aloittaa ennen kahdeksaa ja paluu asemalle olisi hämärän laskeutuessa. Reppuihin pakatut pähkinät ja hedelmät pitäisivät tutkijamme polulla sinne asti. Ensimmäisen päivän pakkaaminen aiheutti keskustelua. Kuinka kuuma tulee? Kuinka paljon vettä tarvitaan mukaan? Ovatko näytepussit ja näytteenkeruulaitteistot mukana? Kenellä on kompassi ja GPS? Lopulta lähdön hetki koitti Päivän tarkoituksena oli tutustua metsäalueeseen, etsiä belgialaisten sinne perustamia plotteja eli tutkimusalueita, kerätä niiltä jäkäliä ja muita kasvinäytteitä biologeille sekä ottaa maantieteilijöiden toimesta hemisfäärikuvia. Saavuimme Ngagaon metsäalueelle, metsänhoitajan majalle, noin 1800 metrin korkeudelle hivenen huonokuntoista tietä. Meitä oli tervehtimässä Kenya Forest Servicen Sylvester kahden assistenttinsa kanssa. He kertoivat omasta, endeemisiin lintulajeihin liittyvästä tutkimuksestaan ja toivottivat meidät tervetulleeksi alueelle. Ngagaon metsäalue on sekametsää, jossa vuorottelevat luonnonlajit, kuten Taber montana sekä eksoottiset, istutetut lajit, kuten erilaiset männyt ja sypressit. Metsän aluskasvillisuus vaihteli riippuen valtalajista. Luonnonlajien alueella aluskasvillisuus oli monipuolista ja runsasta, kun taas mäntyjen ja eukalyptusten kohdalla aluskasvillisuus muuttui kuin veitsellä leikaten niukaksi, kuivaksi kankaaksi, jossa havunneulasmatto loi suomalaisen metsän tunnelmaa. Metsäpeitteen antama varjo sekä korkeutemme meren pinnasta piti lämpötilan metsän siimeksessä miellyttävänä, jopa ajoittain viileänä. Hei kun altistuimme vähänkin suoralle auringon paisteelle, lämpötila nousi huomattavasti. Metsäalueen vaihtelevat korkeuserot hengästyttivät reippaita tutkijoitamme. Alueen alkuperäisiä lajeja on kaadettu rahan toivossa 1900-luvun alkupuolella ja nyt Ngagaossa on enää siellä täällä suuria, lankkujuurisia, isolatvuksisia puuyksilöitä muistuttamassa entisistä ajoista, jolloin alue oli ollut monikerroksista sumusademetsää. Hakkuutöistä oli metsässä muistona syviä sahauskuoppia, joiden avulla massiivisia puita on päästy sahaamaan. Alkuperäislajiston raju hakkaaminen ja istutettujen lajien levinneisyys omalta osaltaan aiheuttavat Taitalla kuivuutta, johon paikalliset ovat havahtuneet elinolojen huonontuessa jatkuvasti. Löysimme ensimmäisen plotin 09.45, jossa saimme harjoitella, miten plotilta kerätään näytteitä ja miten hemisfäärikuvia otetaan. Tämä näytelmä tulisi seuraavan viiden päivän aikana toistumaan lukuisia kertoja. Hemisfäärikuvien ottaminen oli kokonaisuudessaan minulle tuntematon prosedyyri. Kuva otetaan hemisfäärilinssillä eli puolipallolinssillä, joka kattaa 180 astetta. Kuvia otetaan keskeltä plottia sekä jokaisesta plotin kulmasta plotin ollessa neliön mallinen. Plotilta mitattiin myös rinteen kaltevuus klinometrillä sekä rinteen viettosuunta kompassilla. Hemisfäärikuva-aineistolla pyritään mallintamaan metsän lehtipinta-alaa eli kuinka paljon metsä pystyy yhteyttämään. 79

81 Matkapäiväkirjat travel diaries Liikkuminen biologien kanssa on hidasta. Vähintäänkin yksi pylly on jatkuvasti pystyssä kannon tai puskan äärellä ja eipä aikakaan kun ihastunut huudahdus on houkuttanut paikalle jo muutaman pyllyn lisää. Kuvaaminen, kerääminen ja yleinen ihmettely ja lajien tunnistaminen ottaa oman aikansa, joten metsässä liikkumisen tuntinopeus ei ollut päätä huimaavaa. Saavutimme korkeimman kohdan Tätä ennen pysähdyimme ihmettelemään kasvien lisäksi myös aikoinaan asutettua luolaa. Korkeimmalta kohdalta maisema avautui alueen parhaalle maatalousalueelle, laaksoon jossa viljellään erilaisia kaaleja ja maissia, joita viedään myytäviksi jopa Mombasaan asti. Siellä korkeuksissakin äänimaisemassa vallitsi ihmisen toiminnan tuomat äänet. Kukot kiekuivat, moottorisaha surisi, ihmisten nauru ja juttelu kiiri laaksossa lehmien ammunnan siivittämänä. Voimakas mekaaninen ääni lähti maissin jauhamiseen käytettävästä Posho-myllystä. Täältä jatkoimme kulkuamme noin 16 hehtaarin kokoisen palaneen metsäalueen läpi kohti eväskallioita. Eväskallioillamme on paikallisten keskuudessa myös toinen käyttötarkoitus. Nuoret rakastavaiset karkaavat tänne seurustelemaan ahtaiden asumisolojen ja pienten kyläyhteisöiden valvovan silmän alta. Rentouttavan evästuokion jälkeen lähdimme kohti päivän viimeisiä plotteja. Matkan varrella kävelimme koulun pihan läpi, jossa oli iso lauma lapsia huutamassa How are youta. Suuri lapsijoukko liikkui ryhmänä meitä kohti ja perääntyi kiljuen aina jos joku heille vastasi tai lähti kävelemään heitä kohti. Olimme ilmeisen hauskaa seurattavaa naurun määrästä päätellen. Autoille palaaminen tapahtui kullakin omaan tahtiin. Sillä joukkomme erkani loppumatkasta toisistaan. Ansiokkaan metsässä juoksemisen, kartan väärinpäin pitämisen ja sisäisen suuntavaiston avulla kaikki kuitenkin löysivät lopulta autoille. Pyörähdimme päivän lopuksi vielä Wundaniyn kylän keskustassa hedelmätorilla ja kauppa-asioilla. Väsyneet mutta näytteistä ja kokemuksista onnelliset opiskelijat ja professorit olivat silmin nähden tyytyväisiä valmiiksi katettuun illallispöytään. Illan kruunasi monelle ensimmäinen kokemus suomalaisesta saunasta Keniassa. Kuva 1. Ensikosketus Taitan metsiin saatiin Ngangaolla. 80

82 Matkapäiväkirjat travel diaries Vurialla - Keskiviikko Annina Launis Keskiviikko aamu sarasti kirkkaana ja kauniina Taitavuorten tutkimusasemalla. Tuttuun tapaan ympäröivältä asutukselta kantautuvat äänet, kukot ja lehmät, herättivät uuteen päivään. Yö oli ollut huoneessamme yllättävän kylmä ja heräsin kietoutuneena monenmoisiin vaatteisiin ja peitteisiin. Aamutoimet ja maastovalmistelut kävivät tänä aamuna jo varsin joutuisasti, jonkinmoisella rutiinilla, ja kaurapuurokin muistutti enemmän Suomessa totuttua. Aamuauringon jo lämmittäessä pakkauduimme kahteen autoon ja suuntasimme paikallisen oppaan kanssa kohti Vuria vuorta. Kuva 1. Aamun kajo Taitavuorten tutkimusasemalla, kello kuudelta. Vuria on Taitavuoriston korkein huippu, 2208m, ja sen päältä avautuu näköala laajalle alueelle. Aamu oli ainutlaatuisen kirkas - niin kirkas, että Tanzanian rajalla nouseva Kilimanjaro näkyi ajaessamme ylös Vurialle johtavaa tietä. Myöhemmin päivällä tasagoilta nouseva kosteus ja pilvet peittivät lumihuippuisen vuoren. Parkkeerasimme autot vuoren keskirinteen tienoille ja jatkoimme matkaa jalan. Ensimmäinen näytteenkeruupaikka oli Satula-nimisessä puoliaukeassa paikassa. Alueella oli muutamia hyvin vanhoja puita, kuten Maesa lanceolata ja Cupressus lusitanica. Valo ja kosteusolosuhteet olivat suotuisat runsaalle syanojäkälälajistolle ja suvut Sticta, Pseudocyphellaria ja Leptogium olivat paikalla hyvin edustettuina. Puilla viihtyi myös erilaisia karvejäkäliä, muun muassa Parmotrema-suku, sekä rustojäkäliä (Ramalina). 81

83 Matkapäiväkirjat travel diaries Näytepussien täytyttyä Satulassa siirryimme ylemmäs vuoren rinteeseen, kosteanrehevälle näytealalle numero 90. Myös tämä alue oli syanojäkälille sopiva elinympäristö. Alueella oli varttuneita puita ja lahopuuta, muun muassa suurilehtinen Macaranga capensis. Kenttä- ja pensaskerrosta hallitsivat pikkumähkä (Selaginella kraussiana), saniaiset ja Lobelia gibberoa, Suomen rantavesistä tutun nuottaruohon suurikasvuinen sukulainen. Metsän pohja oli kostea ja siinä virtasi pieni puro. Kuva 2: Annan leppoisa hetki näytealalla 90. Runsaasta jäkälälajistosta innostuneina kiipesimme kohti vuoren huippua. Matkalla pysähdyimme kahdelle näytealalle, numeroille 91 ja 92. Näistä ensimmäinen oli kostea notkelma, jonka hallitseva laji oli saniaispuu (Cyathea manniana). Sen sammaleisilla rungoilla viihtyi retkueelle uusi syanojäkäläsuku Peltigera, nahkajäkälät, joita kasvaa yleisenä myös Suomessa. Lajin kiiltävän sileä yläpinta ja (tumma)suoninen alapinta ohuine ritsoidineen kuului Peltigera dolichorrhiza lajille. Ylempänä rinteessä sijaitseva näytealue 92 oli hyvin erilainen. Alue oli puoliavoin, vanhojen pienilehtisten puiden hallitsema valoisa metsäalue. Syanojäkäliä oli runsaasti: Peltigera-, Leptogium-, Coccocarpia-, Parmeliella-, Pannaria- ja Sticta - suvut olivat alueella kaikki edustettuina. Alueelta löytyi myös mielenkiintoinen Normandina -suku, jonka systemaattinen sijoittuminen Ascomycota -kaaressa on epäselvä. Lounaspaikkamme oli erityisen hienolla paikalla Vuria -vuoren huipulla, mistä näköala kantoi yli Taita Tavetan alankojen aina Tanzanian vuoristoihin saakka! Alhaalla näkyi savannialueita, muun muassa Luma luonnonpuisto. Lähialueen maankäyttö mosaiikkimaisine viljelyalueineen oli myös selkeästi havaittavissa. Kasvitieteilijän olo oli paikalla oikein kotoisa: eväitä syötiin kanervan varjossa (Erica mannii), karhunsammalten päällä (ehkä Polytrichum commune), pienten Lobelioiden keinuessa tuulessa. 82

84 Matkapäiväkirjat travel diaries Kuva 3: Kaisa kuvaa kaitafilmillä lounaspaikallamme, Vuria-vuoren huipulla. Siirtyessämme alaspäin vuorelta pysähdyimme kolmella varsin luonnontilaisella metsäalueella. Vurian metsät ovat suojeltuja, mutta alueella on varsin runsaasti vieraslajeja, kuten Cupressus lusitanica ja Acasia mearnsii. Vieraslajit, metsähakkuut ja metsäpalot ovat kuivattaneet ja köyhdyttäneet ekosysteemejä, osaltaan mistä johtuen vettä ei enää riitä alarinteille. Syanojäkäliä näytealoilta kuitenkin löytyi varsin mukavasti, päivän uusina sukuina Lobaria (keuhkojäkälät) ja Erioderma. Viimeisen näytealan (nro.94) vanhalta Acasia mearnsii puulta löytyi laaja kirjo eri jäkäliä: Sticta, Lobaria, kaksi Cladonia lajia (Torvijäkälät), Pseudocyphellaria, isoja Usnea- eli naavakasvustoja, Pannaria ja erilaisia karvejäkäliä. Totesimmekin brittien alueelle istuttaman, nahan parkitsemiseen käytetyn, puulajin olevan varsin sopiva kasvualusta useille jäkäläsuvuille. 83

85 Matkapäiväkirjat travel diaries Fururun metsissä ja jalkapallokentällä Torstai Tuuli Toivonen Torstain aamu valkeni jälleen upean aurinkoisena, tyynenä ja lämpimänä. Edessä oli viimeinen maastotyöpäivä ja illalla tiedossa jalkapallo-ottelu paikallista joukkuetta vastaan. Aamiaisen jälkeen pakkasimme maastokamppeemme jo tottuneesti autoihin ja suuntasimme kohti Fururun metsää. Autot jäivät tien varteen ja jatkoimme jonossa taivaltaen viljelysmaiden halki ylös vuoren rinnettä ihaillen rinteeltä aukeavia maisemia. Kuva 1. Polku Fururulle kulki mutkitellen viljelysten halki. Fururun rinteiltä löysimme odotusten mukaisesti pienen alkuperäismetsän laikun, jossa tutustuimme kasvillisuuteen Joukon ja Petrin johdolla. Metsässä oli hiljaista ja valo siivilöityi metsän pohjalle kauniisti lehvien läpi. Paljon emme silti pysähtyneet ihailemaan, vaan suuntasimme ploteillemme eksoottisen mäntymetsän puolelle. Homma oli jo huomattavasti nopeampaa kuin ensimmäisinä päivinä. Enää ei kameroita ja jalustoja juuri turhaan veivattu ja biologien jäkäläsilmät olivat hyvin virittyneet skannaamaan kiinnostavia kohtia maastossa. Vain valmiiksi merkittyjen plottimerkkien etsintä tuotti haastetta. Onneksi kokeneet ja paikalla aiemmin töitä tehneet avustajat tiesivät mitä etsiä ja suunnilleen mistä plottien pitäisi löytyä. Jyrkissä rinteissä työ sujui välillä rutiinista huolimatta hitaasti ja toisten hikoillessa kameranjalkojen pituutta säätäessä, oli osalla porukasta aikaa köllötelllä hetki maata peittävällä karikematolla. 84

86 Matkapäiväkirjat travel diaries Kuva 2. Henkka (oikealla) ja Pekka eksoottisen metsän plotilla. Jyrkät rinteet ja plottien löytäminen aiheuttivat suurimmat haasteet kenttätyöhön. Mittaukset ja puiden laskut sujuivat viimeisenä kenttätyöpäivänä jo rutiinilla. Pidimme lounastauon huipun kallioilla ja saimme tilaisuuden päivittää kannettavalla koneella myös alueelta tehtyä ilmakuvatulkintaa. Maastotyön merkitys tuli jälleen selväksi, kun pääsimme korjaamaan parin neliömäisen kohteen luokituksen kartalla: Eiväthän ilmakuvasta tulkitut suorakaiteet olleetkaan taloja, vaan kalliosta irronneita ja alas pudonneita lohkareita! Laskeuduimme alas Fururulta toista rinnettä viljelysalueiden halki hiekkatielle. Joukko lapsia oli palaamassa koulusta ja saimme kävelyymme hetkeksi hauskaa seuraa. Edessä oli vielä pieni pisto pois tieltä: Keskellä maissipeltoja, parin sadan metrin päässä tiestä oli metsälaikku, jonka Petri tunsi. Suuntasimme puiden keskelle ja löysimme valtavan lohkareen alta pyhän paikan: kylän pääkalloluolan, johon kylän tärkeiden ihmisten pääkallot kuoleman jälkeen kuulemma kuljetettiin kunniakulkueessa. 85

87 Matkapäiväkirjat travel diaries Kuva 3. Pyhästä metsästä Fururun juurelta löytyi pääkallo poikineen. Pääkalloluolalta suuntasimme takaisin kohti autoja. Matkalla oli pieni aaltopeltikattoinen puoti, josta saimme Fantat kaikille halukkaille. Sitten karautimme takaisin asemalle valmistautumaan illan peliin Taitan joukkuetta vastaan. Kentälle tallustellessamme tunnelma oli iloisen jännittynyt, ainakin jalkapalloa taitamattomien keskuudessa. Kaikkien pelipanosta tarvittiin, sillä pelikonkareita oli vain kourallinen. Saimme vahvistusta Kenistä ja parista paikallisesta ja peli lähti hyvässä hengessä käyntiin. Me saimme punavalkoraidalliset paidat ja paikallisjengi oli sinisissään. Myös paikallisporukka oli sekajoukkue: täälläkin naiset pelaavat! Pekan muistikuvat tiivistävät hyvin tunnelmat kentällä: Taitan porukka antoi ystävällisesti meidän voittaa ottelun. Professori Petri Pellikka viimeisteli mieleenpainuvasti voittomaalin hemisfäärivalokuvaaja Pekka Itkosen oikealta laidalta lähettämästä keskityksestä. Jäkäläasiantuntija Petri Nyqvist kummasteli olosuhteita - kentällä oli lehmän jätöksiä. Kentän laidallakaan ei oltu toimettomina. Kamerat saivat paikalliset koululaiset villeiksi. Temppuilut ja komeat irvistykset tallentuivat muistikorteille konekivääritahtia, kun heput saivat kamerat omiin käsiinsä. Auringon laskiessa nousimme takaisin asemalle, limsan virvoittamina ja iloisina. Hyvä päivä! 86

88 Matkapäiväkirjat travel diaries Kuva 4. Jalkapallokatsomossa ei tarvinnut olla yksin. Kamerat houkuttivat paikalliset pojat paikalle ja Mervi ja Anniina joutuvat vähän väistelemäänkin. Kuva 5. Ottelun päätteeksi varsinkin voittajaporukan hymy oli herkässä. 87

89 Matkapäiväkirjat travel diaries Tsavon retki Perjantai Henri Riihimäki Perjantaina ohjelmassa oli varmasti monen mielestä tutkimusretkemme kohokohta päiväretki Tsavon kansallispuistoon. Tsavon kansallispuisto on jaettu hallinnollisesti kahteen eri osaan, itäiseen ja läntiseen. Me vierailimme itäisessä Tsavossa, joka on suurin Kenian luonnonpuistosta kattaen km 2 kokoisen alueen. Alue vastaa kooltaan yli kolmannesta koko Belgian pinta-alasta, joten pienestä tontista ei ole kyse. Retkueemme sulloutui kolmeen maastoautoon, ja lähdimme matkaan auringon pikkuhiljaa lähestyessä horisonttia. Ensitöiksemme kävimme tankkaamassa autot ja nostamassa käteistä sisäänpääsymaksua varten. Ongelmitta ei selvitty, sillä korttiautomaatti piti professori Rikkisen luottokortista siinä määrin, että päätti pitää sen omanaan. Vaikeuksien ja pienoisen kiireenkin kautta selvisimme portille, tarkalleen kello 06.59, auringon pilkottaessa hieman horisontin yläpuolella. Paras aika villieläinten näkemiseen on huhujen mukaan heti aamusta, tai juuri ennen auringonlaskua. Tällöin ilma on suhteellisen viileää ja eläimet aktiivisimmillaan. Tino, joka toimi yhtenä kolmesta autokuskista, lähti hakemaan autoseurueellemme ajolupaa sekä maksamaan puiston pääsymaksuja. Samalla näimme jo ensimmäiset merkit villieläimistä luonto oli läsnä. Autoseurueemme, johon kuuluivat itseni ja kuskimme lisäksi Pekka, Tuuli sekä Reeta, odotti malttamattomana sisäänpääsyä. Tavoitteena oli bongata ns. Big Five eläimet: elefantti, sarvikuono, puhveli, leijona ja leopardi sekä tietenkin liuta muita eksoottisia eläimiä. Automme vihdoin lipuessa porteista sisään ensimmäisenä meitä tervehtivät mangustit, jotka vartioivat reviiriään kiviröykkiön päältä. Viereisessä pöheikössä käyskenteli kaksi vesiantilooppia ja aamutaivaalla näkyi vielä täyden kuun rippeet. Astuimme avaraan luontoon. Kaksi muuta kuskia, Ken ja Jouko, lähtivät seurueineen posottamaan kohti horisonttia kuin Safari-rallissa konsanaan. Sen sijaan meidän seurueemme otti rauhallisemman strategian, ja lähdimme etenemään kaikessa hiljaisuudella hieman kävelyvauhtia nopeampaa ajaen. Suurin toiveemme oli nähdä leijona, sillä ovathan juuri Tsavon alueen leijonat kaikista leijonista pelätyimpiä. Vuonna 1898 Tsavon alueella rakennettiin Kenian ja Ugandan välistä rautatietä. Kymmeniä ihmisiä menetti tuolloin henkensä leijonien hyökkäyksissä ennen kuin kuulut Tsavon ihmissyöjät saatiin tapetuiksi. Legenda kuitenkin säilyi elossa, ja juuri siksi mekin metsästimme leijonaa, yli sata vuotta myöhemmin. Kuskimme Tino, jolla oli jo lukuisia safareita takanaan, tunsi erilaisia villieläimiä hyvin. Ensimmäisen gasellin osuessa silmiimme Tino tähdensi sen olevan Grantin gaselli. Lisäksi näimme matkallamme keihäsantilooppeja, seeproja, pahkasikoja sekä norsuja. Eräässä kohdassa näimme nämä kaikki eläimet samaan aikaan. Kameroiden suljin lauloi hoosiannaa. Oma lukunsa olivat lukuisat erilaiset linnut joita näkyi sekä lennossa, että akaasiapuiden oksilla päivystämässä. Näimmepä myös yhden matelijan, yli metrin mittaisen liskon, mutta lajista meillä ei ollut tietoa. Hieno se silti oli! 88

90 Matkapäiväkirjat travel diaries Kuva 1. Keihäsantilooppeja matkanvarrelta, taustalla näkyy seeproja. Päivän edetessä poutapilviä alkoi kerääntyä taivaalle. Ilma oli varjossakin reilusti yli 30 C asteista, ja kuumuus autossa melkoinen. Tuuli ja Reeta päättivät kokeilla matkustamista auton katolla, ja pitivätkin sitä erittäin mieluisana kokemuksena, sillä näköesteitä ei ollut ja ilmavirta viilensi oloa mukavasti. Keskipäivän aikaan, ilman ollessa paahtavimmillaan, oli meidänkin hyvä pitää taukoa, sillä myös eläimet tekevät niin. Suuntasimme kohti läheistä joenrantaa, jossa tarjolla olisi kylmiä virvokkeita sekä varjoa. Matkalla törmäsimme professori Rikkisen autoseurueeseen, jolla jälleen kerran oli puhjennut rengas. Jouko yritti tavoittaa Ken(ian) MacGyveria radiopuhelimitse: Ken, we have a flat tyre just after the lions. Leijonia!? Olimme näemmä hetkeä aikaisemmin kuvanneet kirahveja ja kuivunutta joenuomaa, tietämättä että kuvaamiemme pusikoiden takana makasi kolme leijonaa! Ken ei vastannut, ja meidän autossamme ei ollut ylimääräistä vararengasta. Tilanne oli kutkuttava. Tilanneanalyysin tehtyämme päätimme lähteä kohti taukopaikkaa, jossa kerroimme Kenille, että Jouko tarvitsisi apua renkaan kanssa leijonat saivat odottaa. Jäimme pitämään taukoa, kun Ken lähti pelastamaan tilannetta. Noin tuntia myöhemmin virvokkeet oli nautittu, mieli oli virkeä ja rengas vaihdettu. Autokuntamme lähti kohti leijonapaikkaa. Siirryimme Pekan ja Reetan kanssa auton katolle ja tärisevin käsin odotimme leijonia, ja siellähän ne olivat. Onneksemme leijonat eivät keskipäivällä liiku juuri ollenkaan, joten varsinaista vaaraa meille ei luultavasti ollut. Kuvia silti otimme kuin viimeistä päivää. Kuva 2. Odotettu kohtaaminen Tsavon leijonien kanssa. Myöhemmin meitä sivistettiin kertomalla, että auton katolla ei saa matkustaa. Varmaan ihan syystäkin 89

91 Matkapäiväkirjat travel diaries Tässä vaiheessa päivässämme oli jäljellä tehokasta peliaikaa noin nelisen tuntia. Lähdimme kohti virtahepoja ja krokotiilejä, joita ei valitettavasti niiden takuupaikasta tällä kertaa näkynyt, vaikka jostain mutkan takaa virtahepojen pitämä meteli kyllä kuului. Joella peseytymässä ollut elefantti oli hauska näky. Loppuiltapäivästä näimme paljon kirahveja, seeproja ja norsuja sekä erilaisia antilooppeja ja gaselleja. Pienin tapaamamme antilooppi oli dikdik, jonka säkäkorkeus on vain noin senttimetrissä, joten kovin kookkaasta sorkkaeläimestä ei ole kysymys. Retkemme Tsavossa lähestyi päätöstään. Viime metreillä ajoimme valtavien norsulaumojen ohi. Norsuja käveli laskevan auringon värjäämällä tasangolla kymmenittäin, ellei sadoittain. Näky oli vaikuttava, ja oli mukava saada onnistuneelle retkelle arvoisansa päätös. Vielä meitä onnekkaampia olivat Kenin autokunnassa olleet. Ken oli bongannut autostaan puussa makoilevan leopardin, joka lienee kaikista päivän eläimistä harvinaisimpia ja halutuimpia bongauksia. Kirjauduimme ulos puistosta ja pysähdyimme huoltoasemalle ostamaan juotavat. Tämän jälkeen suuntasimme jälleen kohti Tsavon kansallispuistojen välissä olevia Taita-vuoria, ja siellä odottavaa illallista. Kuva 3. Elefantteja käyskenteli paljon Tsavon tasangoilla. Kuva 4. Keskipäivän paahteessa lämpötila lähenteli + 40 celsiusastetta 90