Conservation status of the elegant yellow-black bush-cricket Meruterrana elegans (Orthoptera: Phaneropterinae)—a critically endangered species on Mount Kenya

Two populations of Meruterrana elegans, a monotypic bush-cricket genus, endemic to Mount Kenya in Kenya were surveyed. The species is restricted to Cassipourea forest, a forest community vanishing rapidly on Mount Kenya and with it Meruterrana elegans, which therefore should be included to the IUCN red list of threatened species as Critically Endangered.Keywords: Red list, insects, East Afric

Aboveground Deadwood Biomass and Composition Along Elevation and Land-Use Gradients at Mount Kilimanjaro

Deadwood is an important structural and functional component of forest ecosystems and biodiversity. As deadwood can make up large portions of the total aboveground biomass, it plays an important role in the terrestrial carbon (C) cycle. Nevertheless, in tropical ecosystems and especially in Africa, quantitative studies on this topic remain scarce. We conducted an aboveground deadwood inventory along two environmental gradients-elevation and land use- at Mt. Kilimanjaro, Tanzania. We used a huge elevation gradient (3690 m) along the southern slope of the mountain to investigate how deadwood is accumulated across different climate and vegetation zones. We also compared habitats that differed from natural forsts in land-use intensity and disturbance history to assess anthropogenic influence on deadwood accumulation. In our inventory we distinguished coarse woody debris (CWD) from fine woody debris (FWD). Furthermore, we calculated the C and nitrogen (N) content of deadwood and how the C/N ratio varied with decomposition stages and elevation. Total amounts of aboveground deadwood ranged from 0.07 +/- 0.04 to 73.78 +/- 36.26 Mg ha(-1) (Mean +/- 1 SE). Across the elevation gradient, total deadwood accumulation was highest at mid-elevations and reached a near-zero minimum at very low and very high altitudes. This unimodal pattern was mainly driven by the corresponding amount of live aboveground biomass and the combined effects of decomposer communities and climate. Land-use conversion from natural forests into traditional homegardens and commercial plantations, in addition to frequent burning, significantly reduced deadwood biomass, but not past selective logging after 30 years of recovery time. Furthermore, we found that deadwood C content increased with altitude. Our study shows that environmental gradients, especially temperature and precipitation, as well as different anthropogenic disturbances can have considerable effects on both the quantity and composition of deadwood in tropical forests

Usable wild plant species in relation to elevation and land use at Mount Kilimanjaro, Tanzania

We used the broad elevational gradient of Kilimanjaro ranging from warm tropical lowland to cold Afro-alpine temperature regimes and the occurrence of natural, nearly untouched as well as of anthropogenic and heavily disturbed habitats to study how elevation and disturbance by humans affect the proportion of useful plant species in different habitat types. Of the 962 vascular plant species recorded in our 60 study plots, 563 species turned out to be listed as useful in the literature. We classified these species into six usage categories. With linear models we tested for relationships between the proportion of useful species per plot and elevation for natural habitats, and with analysis of variance we compared the proportion of useful species between plots in disturbed and natural habitats at similar elevation. The proportion of useful species for all usage categories increased from 860 to 2500 m asl and decreased with higher elevation. We also found an overall positive correlation between the number of useful plants and the species richness of our plots. Human-influenced habitats had higher proportions of useful species for all usage categories, except for construction and fuel wood usage which were higher in natural savanna and lower montane forest than in used habitats at these elevations. Given the high proportions of useful species, we conclude that preserving the biodiversity of Kilimanjaro ecosystems is indispensable for maintaining the diversity of useful plants species for the local people who rely on it for food, sustainable access to medicinal, fuel, construction and forage material

Plant water resource partitioning and isotopic fractionation during transpiration in a seasonally dry tropical climate

Lake Chala (3 degrees 19' S, 37 degrees 42' E) is a steep-sided crater lake situated in equatorial East Africa, a tropical semiarid area with a bimodal rainfall pattern. Plants in this region are exposed to a prolonged dry season, and we investigated if (1) these plants show spatial variability and temporal shifts in their water source use; (2) seasonal differences in the isotopic composition of precipitation are reflected in xylem water; and (3) plant family, growth form, leaf phenology, habitat and season influence the xylem-to-leaf water deuterium enrichment. In this study, the delta H-2 and delta O-18 of precipitation, lake water, groundwater, plant xylem water and plant leaf water were measured across different plant species, seasons and plant habitats in the vicinity of Lake Chala. We found that plants rely mostly on water from the "short" rains falling from October to December (northeastern monsoon), as these recharge the soil after the long dry season. This plant-available, static water pool is only slightly replenished by the "long" rains falling from February to May (southeastern monsoon), in agreement with the "two water worlds" hypothesis, according to which plants rely on a static water pool while a mobile water pool recharges the groundwater. Spatial variability in water resource use exists in the study region, with plants at the lakeshore relying on a water source admixed with lake water. Leaf phenology does not affect water resource use. According to our results, plant species and their associated leaf phenology are the primary factors influencing the enrichment in deuterium from xylem water to leaf water (epsilon(1/x)), with deciduous species giving the highest enrichment, while growth form and season have negligible effects. Our observations have important implications for the interpretation of delta(2)H( )of plant leaf wax n-alkanes (delta H-2(wax)) from paleohydrological records in tropical East Africa, given that the temporal variability in the isotopic composition of precipitation is not reflected in xylem water and that leaf water deuterium enrichment is a key factor in shaping delta H-2(wax center dot) The large interspecies variability in xylem-leaf enrichment (24 +/- 28 parts per thousand) is potentially troublesome, taking into account the likelihood of changes in species assemblage with climate shifts

Symbionts and changing environment: Lichen diversity and photobiont associations in tropical mountain ecosystems

Epiphytes comprise a significant component of biodiversity and biomass in tropical forests. They are ecologically important in intercepting and retaining moisture, providing habitat and food for invertebrates, and contributing fixed nitrogen into the ecosystem. Lichens are mutualistic symbioses between lichen-forming fungi (mycobionts) and algae and/or cyanobacteria (photobionts). Most lichen mycobionts are specific in their photobiont choice and the local availability of compatible photobionts may limit their ability to disperse into new habitats. The aims of this study are to 1) provide the first account of lichen symbiont diversity in tropical mountains, with focus on changes along topographic gradients, and 2) elucidate the effects of human induced environmental change to lichen symbiotic organisms, including the effects of expansion of agricultural and other disturbed ecosystems, and changing climate. The results will be a significant contribution to understanding tropical biodiversity since so far very few studies deploying modern molecular biological methods have included lichens from East Africa. Lichens, bryophytes, and free-living cyanobacteria and green algae, along the natural environmental gradient of the southern slope of Kilimanjaro including all main ecosystem types. The sampling is focused on study plots established by the KiLi project . The collected specimens will be studied microscopically, with chemical analyses, and molecular biology methods. So far we have sampled several plots within the natural savanna, maize fields, grassland, and Chagga homegardens (3–5 sampled plots each ecosystem type). The specimens have been studied microscopically. The preliminary results show, that clear differences exist in lichen biota between different plot types: lichen abundance seems to depend especially on presence/absence of woody plants, lichen species on the climate, and lichen diversity on substrate variability. In all studied plots lichens mainly occur epiphytically on shrubs and trees.Non peer reviewe

The Lichen Genus Sticta (Lobariaceae, Peltigerales) in East African Montane Ecosystems

The lichen flora of Africa is still poorly known. In many parts of the tropics, recent studies utilizing DNA methods have revealed extraordinary diversity among various groups of lichenized fungi, including the genus Sticta. In this study, East African Sticta species and their ecology are reviewed using the genetic barcoding marker nuITS and morphological characters. The studied regions represent montane areas in Kenya and Tanzania, including the Taita Hills and Mt. Kilimanjaro, which belong to the Eastern Afromontane biodiversity hotspot. Altogether 14 Sticta species are confirmed from the study region, including the previously reported S. fuliginosa, S. sublimbata, S. tomentosa, and S. umbilicariiformis. Sticta andina, S. ciliata, S. duplolimbata, S. fuliginoides, and S. marginalis are reported as new to Kenya and/or Tanzania. Sticta afromontana, S. aspratilis, S. cellulosa, S. cyanocaperata, and S. munda, are described as new to science. The abundance of new diversity detected and the number of taxa represented by only few specimens show that more comprehensive sampling of the region may be needed to reveal the true diversity of Sticta in East Africa. More generally, our results highlight the need for further taxonomic studies of lichenized fungi in the region

Ecosystem Services and Importance of Common Tree Species in Coffee-Agroforestry Systems: Local Knowledge of Small-Scale Farmers at Mt. Kilimanjaro, Tanzania

Global coffee production, especially in smallholder farming systems, is vulnerable and must adapt in the face of climate change. To this end, shaded agroforestry systems are a promising strategy. Background and Objectives: Understanding local contexts is a prerequisite for designing locally tailored systems; this can be achieved by utilizing farmers’ knowledge. Our objective is to explore ecosystem services (ESs) provided by different shade tree species as perceived by farmers and possible factors (elevation, gender, and membership in local farmers groups) influencing these perceptions. We related these factors, as well as farmers’ ESs preferences, to planting densities of tree species. Materials and Methods: During interviews with 263 small-scale coffee farmers on the southern slope of Mt. Kilimanjaro, they ranked the most common shade tree species according to perceived provision of the locally most important ESs for coffee farmers. We asked them to estimate the population of each tree species on their coffee fields and to identify the three ESs most important for their household. Results: Food, fodder, and fuelwood emerged as the most important ESs, with 37.8% of the respondents mentioning all three as priorities. Density of tree species perceived to provide these three ESs were significantly higher for farmers prioritizing these services compared to farmers that did not consider all three ESs in their top three. Albizia schimperiana scored the highest for all rankings of regulatory ESs such as coffee yield improvement, quality shade provision, and soil fertility improvement. Influence of elevation, gender, and farmer group affiliation was negligible for all rankings. Conclusions: This study shows the need to understand factors underlying farmers’ management decisions before recommending shade tree species. Our results led to the upgrade of the online tool (shadetreeadvice.org) which generates lists of potential common shade tree species tailored to local ecological context considering individual farmers’ needs