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Recent advances in the application of spectral bands from satellite observations and machine learning algorithms (MLA) in the Google Earth Engine (GEE) cloud-computing platform have been demonstrated to enhance the accuracy of mapping forest resources. This study presents a novel method for mapping the natural distribution of highland bamboo (Oldeania alpina) using spectral bands and three machine learning algorithms, namely random forest, gradient tree boosting, and classification and regression tree. First, spectral bands, vegetation indices and textural features including contrast, entropy and inverse difference moment were derived from the Sentinel-2 elevation data. Second, observations were categorized as the dry season (December-February), short rainy season (March-May), main (long) rainy season (June-August), wet season (September-November) and annual composite. Third, the machine learning algorithms were tested using 1882 ground control points collected from field and high spatial resolution images. Finally, the best-performing machine learning algorithm was used to classify and map bamboo forests. The five land cover categories identified were bamboo stands, natural forest, other vegetation, non-vegetated areas and water bodies. The result shows that the random forest classifier is a robust algorithm with an overall accuracy of 94% considering all the annual composite's spectral, vegetation and textural variables. The highland bamboo coverage (91 km2) in the Andracha district provided valuable insights. Bamboo stands were mostly distributed in the southern and southeastern parts of the district. Here, we show that image compositing and multiple input parameters using machine learning techniques can overcome challenges facing land cover classification, which can hinder accurate mapping of Afromontane forests. We conclude that the incorporation of vegetation indices and textural features in land cover classification increases accuracy of mapping natural highland bamboo coverage and distribution. The application of this new method is a promising prospect not only in Ethiopia but also in Afromontane forests elsewhere in Africa. [ABSTRACT FROM AUTHOR]

Climate change impacts are posing greater risks to biodiversity, food security, and livelihood in Africa, specifically in arid and semi‐arid environments. In Ethiopia, the genus Balanites Del., which belongs to the monogeneric family called Balanitaceae, has the multipurpose B. aegyptiaca and B. rotundifolia. However, these species are overlooked and endangered by climate change, and their species distributions are not well documented and understood in Ethiopia. Therefore, this study aimed to model the habitat suitability of these two species using current occurrence data, climate, and landscape data and predict their distribution under climate change. Occurrence points of B. aegyptiaca (n = 224) and B. rotundifolia (n = 80) were collected from field surveys and herbarium. Bioclimatic (WorldClim.v2), soil, and landscape variables were used in the ensemble species distribution models (SDMs) using six algorithms (GLM, GAM, BRT, RF, MARS, and SVM). The ensemble SDMs under the current climate showed that the Central Ethiopian Rift Valley is highly suitable habitats for B. aegyptiaca accounting for an area of 114,517 km2, and the Southern Ethiopian Rift Valley is highly suitable habitats for B. rotundifolia accounting for an area of 41,373 km2. The performance of ensemble SDM under the current climate for B. aegyptiaca showed 0.95 AUC, 0.80 TSS, 0.79 COR, and 0.87 deviance; and that of B. rotundifolia with 0.90 AUC, 0.80 TSS, 0.80 COR, and 0.50 deviance. Temperature annual range (Bio07) and precipitation seasonality (Bio15) for B. aegyptiaca; and precipitation of driest quarter (Bio17) and annual precipitation (Bio12) for B. rotundifolia are the most key bioclimatic variables that affect their distributions. The ensemble SDMs under SSP2‐45 and SSP5‐85 (HadGEM3‐GC31‐LL) climates showed that the highly suitable areas will remain suitable for both species (B. aegyptiaca with 116,934 km2 area cover (ΔA = +2.1%) and 125,757 km2 area cover (ΔA = +7.5%) and B. rotundifolia with 29,547 km2 area cover (ΔA = −28.6%) and 50, 894 km2 area cover (ΔA = +23%), respectively). The findings of this study implicated that the Ethiopian Rift Valley region in general for B. aegyptiaca and the Southern Rift Valley of Ethiopia for B. rotundifolia are suitable areas for conservation and sustainable use of the species. [ABSTRACT FROM AUTHOR]

Organic matter in sedimentary archives is abundantly used to reconstruct paleoenvironmental and climate histories. Thereby, distinguishing between the terrestrial and aquatic origin of sedimentary organic matter is often a prerequisite for robust interpretations. In this case study, we use published data for modern plants and topsoils to identify the terrestrial versus aquatic source of n-alkane and sugar biomarkers in two afro-alpine sediment archives (Lake Garba Guracha and Depression B4) in the Bale Mountains, Ethiopia. The results of our comparative approach show that the long-chain n-alkanes C29, C31, and C33 in the sedimentary archives yielded patterns similar to those typical for the potential terrestrial input. By contrast, the relative abundances of the sedimentary mid-chain n-alkanes C23 and C25, and at least partly C27, are significantly increased compared to the plants and topsoils. This suggests that they are primarily produced by aquatic macrophytes and micro-organisms. The Paq ratio (C23 + C25)/(C23 + C25 + C29 + C31) is validated as a suitable source identification proxy in our study area. The sugar biomarkers xylose (xyl) and arabinose (ara) are abundant in the plant and topsoil samples. By comparison, high relative abundances of fucose (fuc) and rhamnose (rham) are generally only observed in sediments. This indicates that these sugar biomarkers are primarily produced by aquatic macrophytes or micro-organisms. Therefore, the ratio (fuc + rham)/(ara + xyl) is a suitable sugar biomarker proxy for organic matter source identification. The relative abundances of galactose and mannose are systematically decreasing and increasing, respectively, from leaves over O-layers to Ah-horizons. Furthermore, they are not significantly different from the abundances found in the sediments. This hinders terrestrial versus aquatic source identification using galactose and mannose. [ABSTRACT FROM AUTHOR]

Environmental transformations are the results of land-use and land-cover (LULC) changes. This study aims to investigate the LULC changes and associated factors in the Este District in northwestern Ethiopia, for the last four decades (the 1980s to 2020s). The land-use and land-cover classes were analyzed using supervised classification techniques in ERDASS IMAGINE 2015 and ArcGIS 10.3.1, categorizing the Landsat satellite images for 1984, 2000, and 2018 into six cover classes: settlement, forests-shrublands, cropland, grassland, bare land, and water body. We used a historical Google map, topo-sheets, and ancillary data to verify the classification accuracies for 1984, 2000, and 2018, respectively. The climate and demographic data were obtained from the Ethiopian Meteorological Station and Ethiopian Statistical Agency, respectively. In addition, data from key informant interviews and focus group discussions were also used to understand the local community experiences and perceptions toward LULC changes. The values of each LULC class were correlated with the demographic and climatic variables, using simple correlation analysis to evaluate the impact of demographic and climatic conditions on LULC changes. The analysis indicated that the least and largest classes of LULC in Este District were water bodies (mean cover = 1.9 km2) and croplands (mean cover = 791.7 km2), respectively. Cropland coverage increased by 2% in 2000, then decreased by 11% in 2018. Between 1984 and 2018, the grasslands and settlements increased by 22% and 0.5%, respectively. Half of the bare land and one-tenth of the forests-shrublands also decreased over the last four decades (the 1980s to 2020s). As a result, the original croplands and forests–shrublands classes (11% each) before 2000 were converted into new grasslands and croplands after 2018, respectively. The study indicated that precipitation, solar radiation, and population growth are the potential drivers, and the perceptions of local communities are nearly in line with the statistical analysis results. Alternative income sources, such as tourism and carbon trading and the participation in afforestation programs, could reverse the situation in the study area. [ABSTRACT FROM AUTHOR]

This study aimed to understand the impact of shrub encroachment on native species in the Guassa Community Conservation Area in Ethiopia. We assessed the soil seed bank composition and density across different elevations and aspects, and management systems within the area. The vegetation was stratified and eight blocks were selected across a range of elevation (<3350 m and >3350 m) and aspect (northeast, northwest, southeast, southwest). Within each block we established twenty 5m x 5m plots for a total of 160. We then collected soil samples from five subplots (1 m x 1 m) at three depths (0–3 cm, 3–6 cm and 6–9 cm) for a total of 480 samples, which were established in pots in greenhouse. We calculated species abundance by totaling the number of seedlings that emerged from each sample. To determine the variability in the abundance of Festuca macrophylla and Helichrysum splendidum in the soil seed bank along altitudinal gradient, we used two-way ANOVA using SAS statistical software version 9.0.1. Shannon diversity index was used to determine species diversity in the soil seedbank. After counting all the seeds, we identified 74 plant species represented in the soil seedbank which belong to 55 genera and 23 families. Eleven species are endemic to Ethiopia. At the lower elevation range, the effects of aspect (P <0.0088) and soil depth (P <0.005) are not significant to determine the abundance of seeds of H. splendidum and F. macrophylla. But when the factors are segregated, both aspect and soil depth play a significant role (p<0.0001) regarding the abundance of the seeds of the competing species at lower elevation. At higher elevation, only the effect of soil depth is significant (P<0.0001) for determining the abundance of H. splendidum. Soil depth and aspect have no significant effects on soil seed bank abundance at this elevation. [ABSTRACT FROM AUTHOR]

Background: Ethiopia is endowed with much plant diversity. The insignificant number of studies on wild edible plants with their ethnobotanical perspectives indicated that this plant diversity comprised only hundreds of wild edible plants used to supplement food sources for the local community under different conditions. There still need to be further investigations throughout the country when compared to the total area and cultural diversity of the country. However, they are seriously under pressure due to different natural and human influences. Therefore, the study was conducted to document underutilized wild edible plants along with their associated indigenous knowledge and explore threats to them in Midakegn District. Methods: A questionnaire survey, semi-structured interviews, a market survey, score ranking, and focused group discussions were employed for data collection. Statistical analysis of ethnobotanical knowledge mean variation between different informant groups was computed by using one-way ANOVA in the IBM SPSS Statics version 24 package. Results: A total of fifty underutilized wild edible plants belonging to 39 genera and 30 families were collected, recorded, and documented. The families Moraceae (four), Fabaceae, Flacourtaceae, Myrtaceae, Rosaceae, and Tiliaceae (each three) represented the highest number of species. It comprised shrubs (44%), trees (36%), herbs (18%), and epiphytes (2%). Fruits (62.3%) were found to be the most frequently used and mostly taken raw, fresh, or dried. These edible resources were consumed to supplement staple foods (67.3%), whereas 25% were used as emergency foods. The majority of species (96%) had multiple uses in addition to their edibility. A significantly higher (P < 0.05) number of underutilized wild edible plants were cited by males than females, by key informants than generals, elders than youngsters, illiterate than literate, and poorer than other wealth class groups of the community. Priority rankings indicate that agricultural expansion, fuel wood harvest, overgrazing, and selective harvesting are the most threatening factors to underutilized wild edible plants. Conclusions: Fifty underutilized wild edible plants, along with their associated indigenous knowledge, were recorded. Local people utilize them for supplementing staple food, as emergency food, to get relief, trust, and chew during drought. But they are mainly threatened by different human activities in the study area. [ABSTRACT FROM AUTHOR]

Conventional wisdom states that genetic variation reduces disease levels in plant populations. Nevertheless, crop species have been subject to a gradual loss of genetic variation through selection for specific traits during breeding, thereby increasing their vulnerability to biotic stresses such as pathogens. We explored how genetic variation in Arabica coffee sites in southwestern Ethiopia was related to the incidence of four major fungal diseases. Sixty sites were selected along a gradient of management intensity, ranging from nearly wild to intensively managed coffee stands. We used genotyping‐by‐sequencing of pooled leaf samples (pool‐GBS) derived from 16 individual coffee shrubs in each of the 60 sites to assess the variation in genetic composition (multivariate: reference allele frequency) and genetic diversity (univariate: mean expected heterozygosity) between sites. We found that genetic composition had a clear spatial pattern and that genetic diversity was higher in less managed sites. The incidence of the four fungal diseases was related to the genetic composition of the coffee stands, but in a specific way for each disease. In contrast, genetic diversity was only related to the within‐site variation of coffee berry disease, but not to the mean incidence of any of the four diseases across sites. Given that fungal diseases are major challenges of Arabica coffee in its native range, our findings that genetic composition of coffee sites impacted the major fungal diseases may serve as baseline information to study the molecular basis of disease resistance in coffee. Overall, our study illustrates the need to consider both host genetic composition and genetic diversity when investigating the genetic basis for variation in disease levels. [ABSTRACT FROM AUTHOR]

Echinops kebericho is a narrow‐range multipurpose medicinal plant confined to Ethiopia. Intense land use change and overharvesting for traditional medicine have resulted in narrow distributions of its populations. It is a threatened species with a decreasing population trend. This study aims to map its potential distribution, which is key to guide conservation efforts and sustainable use. We modeled the potential distribution of E. kebercho using the maximum entropy model (MaxEnt) employing 11 less correlated predictor variables by calibrating the model at two complexity levels and replicating each model 10 times using a cross validation technique. We projected the models into the whole of Ethiopia and produced binary presence–absence maps by classifying the average map from both complexity levels applying three threshold criteria and ensembling the resulting maps into one for the final result. We mapped suitable habitat predicted with high certainty and identified local districts where E. kebericho can be cultivated or introduced to enhance its conservation. We estimated that E.kebercho has about 137,925 km2 of suitable habitat, mainly concentrated in the western highlands of the Ethiopian mountains. Our models at both complexity levels had high average performances, AUC values of 0.925 for the complex model and 0.907 for the simpler model. The variations in performance among the 10 model replicates were not remarkable, an AUC standard deviation of 0.040 for complex and 0.046 for simple model. Although E. kebericho is locally confined, our models predicted that it has a remarkably wider potential distribution area. We recommend introducing E. kebericho to these areas to improve its conservation status and tap its multiple benefits on a sustainable basis. Locally confined threatened plants and animals likely have wider potential distributions than their actual distributions and thus similar methodology can be applied for their conservation. [ABSTRACT FROM AUTHOR]

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Bamboos provide a number of ecosystem services, including the provision of a permanent carbon (C) sink. The present study was undertaken in the Sheka forest, currently recognized as a UNESCO Biosphere Reserve. The objectives of this study were to: (1) develop species- and site-specific allometric models for biomass estimation and (2) quantify the carbon storage capacity of highland bamboo stands. A total of 12 plots each measuring 10 m x 10 m were established at a distance of 200 m in the forest. 96 culms were harvested for the development of biomass estimation equations. Litter samples were collected in 1 m x 1 m subplots, while soil samples were collected at 0–10, 10–20, 20–40, and 40–60 cm soil depths for determination of soil organic carbon (SOC) contents. The estimated mean DBH, basal area and plant height were 7.0 cm, 53.2 m2 ha−1 and 12.9 m, respectively. The study has established allometric scaling of plant height with stem diameter in highland bamboo. It has also established that the allometric model is superior to commonly used non-linear H-DBH models. Aboveground biomass was estimated at 93 Mg ha−1 with mean C stocks of 43.7 Mg ha−1. The estimated below-ground biomass was 18.6 Mg ha−1 with C stocks of 8.7 Mg ha−1. The C stocks in the litter layer were estimated at 1.57 Mg ha−1. Average soil C storage was estimated at 388.12 Mg ha−1 within the 0–60 cm soil depth. In total, the natural highland bamboo stands store approximately 442.1 Mg C ha−1. The estimated C stocks were comparable with values reported for bamboos in Ethiopia and elsewhere. It is concluded that natural highland bamboo stands play a significant role as carbon sinks. The insights gained in this study are expected to be applicable to Afromontane ecosystems where highland bamboo occurs in Africa. Highland bamboo (Oldeania alpina) is a conspicuous element of Afromontane vegetation in Africa We developed models for estimating biomass carbon (C) stocks in highland bamboo stands We estimated biomass C stock of highland bamboo stands at 52.5 Mg ha−1 and litter C at 1.6 Mg ha−1 Soil organic C stock of highland bamboo stands was 388.1 Mg ha−1 Total system C in highland bamboo stands was over 442 Mg ha−1 [ABSTRACT FROM AUTHOR]

Epiphytes colonize canopy trees, provide substantial ecosystem services in production and nutrient cycling, contribute as energy sources, shelter and breeding sites for pollinating birds, bats and ants. Despite this, information on their diversity is patchy. Therefore, this study was investigated vascular epiphytes diversity in Kafa biosphere reserve and nearby coffee agroecosystem. Seventy-two matured trees were systematically selected and assessed for standardized, rapid and representative assessment of vascular epiphytes. 10 × 10 m plots were established at each selected tree understory and each tree was climbed using single rope technique. Characteristics of the phorophytes such as tree height, diameter at breast height, bark rugosity, tree vertical zones and crown architecture were measured. Statistical analyses mainly generalized linear mixed model, canonical analysis and Principal component analysis in R program were used for data analysis. A total of 63 species belonging to 24 genera and 13 families were recorded. Orchidaceae was the dominant family followed by Piperaceae, Polypodiaceae and Lycopodiaceae in terms of species richness and frequency, whereas families such as Adiantaceae, Oleandraceae and Vittariaceae were poorly represented. Species richness and frequency of Vascular epiphytes were significantly lower (P = 0.003) on remnant trees as compared with forest trees. We postulate that changes in microclimate resulting from habitat fragmentation can cause significant reduction in these canopy dwelling and structurally dependent organisms. Conservation of forests with large but slow growing old trees was crucial to maintain habitat specialist vascular epiphytes. [ABSTRACT FROM AUTHOR]

Climate warming threatens the future sustainability of mountains, and tropical mountains are particularly threatened with loss of biodiversity and associated ecosystem services. Conservation biologists increasingly turn to habitat suitability models to guide the establishment and assessment of protected area networks to protect the highest number of species, yet this focus often neglects the values, attitudes, and beliefs of the people living around protected areas. If we consider protected areas as dynamic social–ecological systems, habitat suitability modeling for conservation planning must pay greater attention to the role of biocultural diversity, rather than biodiversity alone. Here, we describe a conservation assessment of the Afroalpine grassland ecosystem in the northern highlands of Ethiopia. We use a cultural keystone species known as guassa grass (Festuca macrophyhlla) to focus our modeling efforts and evaluate the potential distribution of this endemic species in relation to current national and community-based protected areas. Our model performed highly according to the area under the curve (AUC = 0.96), yet nearly 80% of highly suitable guassa habitat falls outside the range of our training data and thus must be interpreted conservatively. We found that guassa grass distribution is primarily limited by low mean temperature in the warmest quarter (BIO10, 36.7%), high precipitation in the wettest quarter (BIO16, 21%), and low precipitation in the driest quarter (BIO17, 15.6%). As climate change causes rapid warming at high elevations and alters rainfall patterns in the Ethiopian highlands, we urge managers to carefully monitor the changing populations of guassa grass to evaluate whether the species is experiencing an extinction debt. We also recommend four additional areas as potential community-based conservation areas, with government and NGO support for peer-to-peer communication networks. Spatially explicit modeling may be a valuable tool to determine whether these existing and proposed protected areas can sustain future populations of guassa grass. [ABSTRACT FROM AUTHOR]

Continuing climate change may cause shifts in the adaptive ranges of plant species. But this impact is less understood for many species in the tropics. Here, we examined the distribution of the current and future potential suitable habitats of two native forest spices Piper capense and Aframomum corrorima. We have used MaxEnt software to predict the current and future suitable habitats of these species. Two future climate change scenarios, that is, middle (Representative Concentration Pathway [RCP 4.5]) and extreme (RCP 8.5) scenarios for years 2050 and 2070, were used. A total of 60 and 74 occurrence data of P. capense and A. corrorima, respectively, and 22 environmental variables were included. The effects of elevation, solar radiation index (SRI) and topographic position index (TPI) on suitable habitats of these species were tested using linear model in R. Precipitation of the driest quarter, SRI and TPI significantly affect future suitable habitats of P. capense and A. corrorima. Furthermore, there are significant elevational shifts of suitable habitats for both species under future scenarios (P < 0.001). These novel suitable habitats are located in moist Afromontane and Combretum-Terminalia vegetations. Our results suggest that conservation planning for these species should consider climate change factors including assisted migration. [ABSTRACT FROM AUTHOR]

Background: The study aimed at documenting the indigenous and local knowledge and use of traditional medicinal plants for treating human and livestock ailments in Dawuro Zone of Ethiopia. Methods: A survey was conducted among traditional healers and native administrators through discussion, interviews, and field observations. The snowball sampling technique was used to select 384 traditional healers in purposefully selected 50 villages spanning seven districts for face-to-face individual interviews. The chi-square test was applied to establish associations between traditional healers' demographics, the distance between the village site and the nearest natural forest and a health center, and SPSS V.20 software was used for the analysis. Results: The traditional healers of the study area reported the use of 274 traditional medicinal plant species belonging to 217 genera and 82 families. Asteraceae (11.68%), Fabaceae (9.49%), and Lamiaceae (9.12%) were the foremost frequently used families. Herb species (54.8%) and leaves (65%) were predominantly sourced from the wild environment. The quantity of medicinal plants used (x2 = 278.368, df = 20, P = 0.000) and years of (experience in) traditional healing using herbs (x2 = 76.358, df = 10, P = 0.000) varied with distance from the natural forests. The service charge for healing had strong positive association (x2 = 24.349, df = 5, P = 0.000) with healer's age (x2 = 309.119, df = 184, P = 0.000) and educational level (x2 = 851.230, df = 598, P = 0.000) with distance of traditional healer's residence from the medical institution. The agricultural activities, urbanization, low or no charge for the healing service, the secrecy and oral transfer of the knowledge, and the demand for medicinal and other multiple purposes species were some of the factors threatening the resource and the associated knowledge as well as the service in the study area. Conclusion: There are diversified traditional medicinal plants applied for healthcare of the community and domestic animals of the study area. The source of remedies mostly depends on herbs of natural forests, and the leaf was the most frequently used plant part. Developing conservation intervention and sustainable systems of utilization is needed for multipurpose medicinal plants. Finally, integrating with modern system and formalizing, legalizing, and capacitating the traditional medicine practitioners are needed for access of primary healthcare systems to rural communities. [ABSTRACT FROM AUTHOR]

This research was done in Arsi-Bale Massif remnant vegetation of southeast Ethiopia to investigate vascular plant diversity and endemism in forest patch, riverine, and grazing land-use types. A total of 126 quadrats, each with 900 m2 (30 m × 30 m), were selected systematically along the altitudinal gradient. Shannon Weiner Diversity index and R Package 3.2 were applied to analyze species composition and diversity, whereas the similarity ratio among land use and other related vegetation was determined using Sorensen's index. From the study, 382 vascular plant species under 223 genera and 92 families were identified. The growth forms revealed that there were 118 woody (26 trees, 10 lianas, and 82 shrubs) and 239 herbaceous species of plant. Of these, 216, 165, and 154 species are shared by riverine, forest patch, and grazing land-use types, respectively. Asteraceae with 68 species was the most dominant family in the present study, followed by Poaceae, Lamiaceae, and Cyperaceae with 30, 21, and 13 species, respectively. Forty-four endemic species were documented in this study. According to the IUCN Red List, 22 species were not evaluated; 10 species were least concerned; 1 species was endangered; and 1 species was vulnerable, while 4 species have been categorized as not threatened. The highest similarity was observed between grazing and riverine land-use types; this may be due to the presence of many adjacent plots in both land use, associated mechanisms of adaptation, and requirements for species occurrence. Moreover, the floristic composition similarity of the study area in comparison with other vegetation types of Ethiopia shows variation (Ss = 0.223–0.526), maybe due to climatic variation, ecological distance, and disturbances. Generally, the total diversity and evenness of the studied remnant vegetation were 2.917 and 0.948, respectively. This lower diversity value clearly indicates that there are many human-induced factors deteriorating the plant species of the studied vegetation. Therefore, the concerned body of the government should work with local farmers to conserve the remaining plant species including many endemic species by developing appropriate conservation and management plans. [ABSTRACT FROM AUTHOR]

Highland bamboo (Oldeania alpina formerly Arundinaria alpina or Yushania alpina) is a species of significant conservation value in Afromontane ecosystems across Africa. It also plays a significant role in the livelihoods of local communities. However, global climate change is anticipated to alter its ecological niche, leading to range shifts and possible habitat contractions. This study aimed to identify potentially suitable habitats for highland bamboo in Ethiopia, determine the resilience of the species under climate change, and establish the environmental factors affecting its habitat. Species distribution modeling (SDM) was implemented in the SDM R package using 231 georeferenced presence records together with climate, topographic, and soil data. To assess climate change risks to the species, predictive models were developed assuming climate scenarios for 2061–2080 under two shared socio-economic pathways (SSPs), namely, SSP2-45 and SSP5-85. The results indicated that highland bamboo mainly grows in high elevation areas with altitudes of 2100–3100 m asl with mean annual temperatures of 11.5–19.3 °C, annual precipitation of 873–1962 mm, precipitation of the driest quarter of 36–147 mm, soil pH of 5.6, and soil CEC of 30.7 cmolc/kg. The current potentially suitable habitat for this species in Ethiopia was estimated at 61,831.58 km2, with the majority of habitats being in the southern and southwestern parts of the country. Our models predicted that the suitable habitat will shrink by 13.4% under the SSP5-85 scenario, while potential new suitable areas for this species were identified under the SSP2-45 scenario. Future vulnerable areas were mostly found in central Ethiopia. Based on the predictions, we conclude that most of the suitable habitats for highland bamboo will remain suitable between the years 2061 and 2080. [ABSTRACT FROM AUTHOR]

Tropical agroforestry systems provide farmers with resources for their livelihoods, but are also well‐recognized as refuges for biodiversity. However, the relationship between yield and biodiversity might be negative in these systems, reflecting a potential trade‐off between managing for increased yield or biodiversity. The potential for synergies will depend partly on the shape of the biodiversity–yield relationship, where a concave relationship suggests a faster decline in biodiversity with increasing yields than a linear or convex shape.We studied the relationship between biodiversity (plant species richness and composition) and coffee yield along a gradient of management in south‐western Ethiopia, coffee's native range. We inventoried species richness and community composition of woody plants, herbaceous plants and bryophytes at 60 sites. We also measured coffee management‐related variables and assessed coffee yield for 3 consecutive years at each site.Species richness of woody plants had a concave relationship with coffee yield, that is, tree richness declined fast initially before levelling out at higher yields, whereas there was no relationship between coffee yield and species richness of herbaceous plants or bryophytes. Species composition of woody plants, herbaceous plants and bryophytes all had a concave relationship with coffee yield.From a methodological perspective, we found that multi‐year data on yield were necessary to reliably assess the relationship between biodiversity and yield, and that the number of coffee shrubs or coffee dominance were poor proxies for yield when trying to capture the biodiversity–yield relationship.Synthesis and applications. The concave relationship between biodiversity components (species richness and composition) and yield suggests that there is a strong conflict between the goals of increasing production and conserving biodiversity. However, it is important to recognize that this pattern is largely driven by the very low‐yielding sites in natural forests. Here, even minor intensification of coffee management seems to rapidly erode biodiversity. Along the rest of the productivity gradient, there was generally no negative relationship between yield and biodiversity, implying opportunities for developing strategies for increasing yields without biodiversity loss. [ABSTRACT FROM AUTHOR]

Low-altitude lakes in eastern Africa have long been investigated and have provided valuable information about the Late Quaternary paleohydrological evolution, such as the African Humid Period. However, records often suffer from poor age control, resolution, and/or ambiguous proxy interpretation, and only little focus has been put on high-altitude regions despite their sensitivity to global, regional, and local climate change phenomena. Here we report on Last Glacial environmental fluctuations at about 4000 m asl on the Sanetti Plateau in the Bale Mountains (SE Ethiopia), based on biogeochemical and palynological analyses of laminated lacustrine sediments. After deglaciation at about 18 cal kyr BP, a steppe-like herb-rich grassland with maximum Chenopodiaceae/Amaranthaceae and Plantago existed. Between 16.6 and 15.7 cal kyr BP, conditions were dry with a desiccation layer at ~ 16.3 cal kyr BP, documenting a temporary phase of maximum aridity on the plateau. While that local event lasted for only a few decades, concentrations of various elements (e.g. Zr, HF, Nb, Nd, and Na) started to increase and reached a maximum at ~ 15.8–15.7 cal kyr BP. We interpret those elements to reflect allochthonous, aeolian dust input via dry northerly winds and increasingly arid conditions in the lowlands. We suggest an abrupt versus delayed response at high and low altitudes, respectively, in response to Northern Hemispheric cooling events (the Heinrich Event 1). The delayed response at low altitudes might be caused by slow negative vegetation and monsoon feedbacks that make the ecosystem somewhat resilient. At ~ 15.7 cal kyr BP, our record shows an abrupt onset of the African Humid Period, almost 1000 years before the onset of the Bølling–Allerød warming in the North-Atlantic region, and about 300 years earlier than in the Lake Tana region. Erica pollen increased significantly between 14.4 and 13.6 cal kyr BP in agreement with periodically wet and regionally warm conditions. Similarly, intense fire events, documented by increased black carbon, correlate with wet and warm environmental conditions that promote the growth of Erica shrubs. This allows to conclude that biomass and thus fuel availability is one important factor controlling fire events in the Bale Mountains. [ABSTRACT FROM AUTHOR]

Context: Human disturbances can have large impacts on forest structure and biodiversity, and thereby result in forest degradation, a property difficult to detect by remote sensing. Objectives: To investigate spatial variation in anthropogenic disturbances and their effects on forest structure and biodiversity. Methods: In 144 plots of 20 × 20 m distributed across a forest area of 750 km2 in Southwest Ethiopia, we recorded: landscape variables (e.g., distance to forest edge), different human disturbances, forest structure variables, and species composition of trees and epiphyllous bryophytes. We then first assessed if landscape variables could explain the spatial distribution of disturbances. Second, we analysed how forest structure and biodiversity were influenced by disturbances. Results: Human disturbances, such as coffee management and grazing declined with distance to forest edges, and penetrated at least a kilometer into the forest. Slope was not related to disturbance levels, but several types of disturbances were less common at higher elevations. Among human disturbance types, coffee management reduced liana cover and was associated with altered species composition of trees. The presence of large trees and basal area were not related to any of the disturbance gradients. Conclusions: Although most anthropogenic disturbances displayed clear edge effects, surprisingly the variation in the chosen forest degradation indices were only weakly related to these disturbances. We suggest that the intersection between edge effects and forest degradation is very context specific and relies much on how particular societies use the forests. For example, in this landscape coffee management seems to be a key driver. [ABSTRACT FROM AUTHOR]

While top‐down control plays an important role in shaping both natural and agricultural food webs, we lack insights into how top‐down control effects vary across spatial scales. We used a multi‐scale survey of top‐down control of coffee pests and diseases by arboreal ants to examine if colony location creates a small‐scale mosaic in top‐down control around trees and if the strength of that control varies between sites at the landscape scale. We investigated pest and disease levels on coffee shrubs at different distances from shade trees with and without a Crematogaster spp. ant colony in 59 sites along a coffee management intensity gradient in southwestern Ethiopia. Within sites, ants significantly suppressed herbivory and coffee leaf rust at distances less than 10 m from nesting trees. Top‐down control varied between sites, with stronger top‐down control of free‐feeding herbivory near ant colonies at sites with lower management intensity and stronger top‐down control of a skeletonizer at sites with higher canopy cover. We conclude that the strength of top‐down control by ants is highly heterogeneous across spatial scales, as a consequence of the biology of the predator at the small scale and herbivore density or changes in herbivore–ant interactions at the landscape scale. [ABSTRACT FROM AUTHOR]

Questions: In some fire-prone ecosystems, bryophytes play a crucial role by providing the surface fuel that controls the fire return interval. Afroalpine heathlands are such an ecosystem, yet almost nothing is known about the bryophytes in this system. We do not know the level of species richness, or if there is a successive accumulation of species over time, or if some species are adapted to specific phases along the successional gradient, for example early-successional species sensitive to competition. Location: Afroalpine heathlands in Ethiopia. Methods: We made an inventory of all bryophytes in 48 plots of 5 m × 5 m, distributed along a chronosequence from 1 to 25 years post fire. The heathlands are located between 3500 m and 3800 m a.s.l. and are managed by traditional pasture burning with fire intervals of 8–20 years. Results: We found in total 111 taxa of bryophytes. Post-fire mortality was almost 100%. The youngest plots had only a few cosmopolitan species often found after fire. Initially, species richness increased monotonically while starting to level off around 15 years after fire, when many plots had around 30 species and a high cover of Breutelia diffracta, which is a key ground-living species, important as surface fuel. Most species were found with sporophytes, a pattern even stronger for the most frequent species. Conclusions: Interestingly, bryophyte diversity is already remarkably high by only 15 years after total eradication. The relatively slow accumulation of species in the first years after fire suggests that dispersal in space, and not time, is the major mechanism by which sites regain their diversity (i.e. spore banks play a smaller role than colonization of wind-borne spores). This indicates that the high species richness is built up through colonization from surrounding heathlands, and perhaps also from higher-altitude alpine grasslands and lower-altitude forests, and that the bryophyte diversity in this system is maintained by the traditional fire and grazing management. [ABSTRACT FROM AUTHOR]

The hydrogen isotopic composition of leaf wax–derived n-alkane (δ2Hn-alkane) and oxygen isotopic composition of hemicellulose–derived sugar (δ18Osugar) biomarkers are valuable proxies for paleoclimate reconstructions. Here, we present a calibration study along the Bale Mountains in Ethiopia to evaluate how accurately and precisely the isotopic composition of precipitation is imprinted in these biomarkers. n-Alkanes and sugars were extracted from the leaf and topsoil samples and compound–specific δ2Hn-alkane and δ18Osugar values were measured using a gas chromatograph–thermal conversion–isotope ratio mass spectrometer (GC–TC–IRMS). The weighted mean δ2Hn-alkane and δ18Osugar values range from − 186 to − 89‰ and from + 27 to + 46‰, respectively. Degradation and root inputs did not appear to alter the isotopic composition of the biomarkers in the soil samples analyzed. Yet, the δ2Hn-alkane values show a statistically significant species dependence and δ18Osugar yielded the same species–dependent trends. The reconstructed leaf water of Erica arborea and Erica trimera is 2H– and 18O–enriched by + 55 ± 5 and + 9 ± 1‰, respectively, compared to precipitation. By contrast, Festuca abyssinica reveals the most negative δ2Hn-alkane and least positive δ18Osugar values. This can be attributed to "signal–dampening" caused by basal grass leaf growth. The intermediate values for Alchemilla haumannii and Helichrysum splendidum can be likely explained with plant physiological differences or microclimatic conditions affecting relative humidity (RH) and thus RH–dependent leaf water isotope enrichment. While the actual RH values range from 69 to 82% (x̄ = 80 ± 3.4%), the reconstructed RH values based on a recently suggested coupled δ2Hn-alkane –δ18Osugar (paleo–) hygrometer approach yielded a mean of 78 ± 21%. Our findings corroborate (i) that vegetation changes, particularly in terms of grass versus non–grassy vegetation, need to be considered in paleoclimate studies based on δ2Hn-alkane and δ18Osugar records and (ii) that the coupled δ2Hn-alkane –δ18Osugar (paleo–) hygrometer approach holds great potential for deriving additional paleoclimatic information compared to single isotope approaches. [ABSTRACT FROM AUTHOR]

Ethiopia aims to restore 15 million ha degraded forests and woodlands, but effects on the potentially contrasting goals of long-term carbon storage, biodiversity and sustainable livelihoods are unknown. To quantify the effects of grazing exclusion on vegetation and fire behaviour, we established six 30 × 30 m fenced exclosures with grazed controls, in a mesic wooded savanna. Experimental burns were done after 1.5 years. Tree seedlings were few but more common inside fences. Field layer cover and biomass increased inside fences, and grass species increased in numbers and cover. Fire intensity was higher inside fences, killing shrubs and saplings but not mature trees. Interviews confirmed that overgrazing has resulted in "cool fires", causing shrub encroachment. High-intensity fires occurred in the 1980s after a zoonotic disease killed most livestock. Short-term increase in carbon storage through fire and grazing exclusion may lead to loss of pasture, and in the long-term increased wildfire risk. [ABSTRACT FROM AUTHOR]

East Africa is an underrepresented region in respect of monitoring the stable isotopic composition of precipitation (δ18Oprec and δ2Hprec). In 2017, we collected precipitation samples from ten weather stations located along an altitudinal transect ranging from 1304 to 4375 m a.s.l. The δ18Oprec and δ2Hprec values varied from –8.7 to +3.7 ‰ and –38 to +29 ‰, respectively. The local meteoric water line is characterised by a lower slope, a higher intercept and more positive d-excess values (δ2H = 5.3 ± 0.2 * δ18O + 14.9 ± 0.9) compared to the global meteoric water line. Both altitude and amount of precipitation clearly correlate with our isotope data. However, the δ18Oprec and δ2Hprec values show at the same time a seasonal pattern reflecting rainy versus dry season. More enriched isotope values prevailed shortly after the end of the dry season; more depleted isotope values coincided with high precipitation amounts recorded in May, August and September. Moreover, HYSPLIT trajectories reveal that during the dry season water vapour originates primarily from the Arabian Sea, whereas during the wet season it originates primarily from the Southern Indian Ocean. These findings challenge the traditional amount effect interpretation of paleoclimate isotope records from East Africa and rather point to a previously underestimated source effect. [ABSTRACT FROM AUTHOR]

Distantly related lineages of the enigmatic giant rosette plants of tropical alpine environments provide classical examples of convergent adaptation. For the giant senecios (Dendrosenecio), the endemic landmarks of the East African sky islands, it has also been suggested that parallel adaptation has been important for within-lineage differentiation. To test this hypothesis and to address potential gene flow and hybridization among the isolated sky islands, we organized field expeditions to all major mountains. We sampled all currently accepted species and all but one subspecies and genotyped 460 plants representing 109 populations. We tested whether genetic structuring corresponds to geography, as predicted by a parallel adaptation hypothesis, or to altitudinal belt and habitat rather than mountains, as predicted by a hypothesis of a single origin of adaptations. Bayesian and Neighbor-Net analyses showed that the main genetic structure is shallow and largely corresponds to geography, supporting a hypothesis of recent, rapid radiation via parallel altitude/habitat adaptation on different mountains. We also found evidence for intermountain admixture, suggesting several long-distance dispersals by wind across vast areas of unsuitable habitat. The combination of parallel adaptation, secondary contact, and hybridization may explain the complex patterns of morphological variation and the contradicting taxonomic treatments of these rare enigmatic giants, supporting the use of wide taxonomic concepts. Notably, the within-population genetic diversity was very low and calls for increased conservation efforts. [ABSTRACT FROM AUTHOR]

Today, on the Sanetti Plateau in the Bale Mountains of Ethiopia, only fragmented patches of Erica species can be found at high altitudes (between 3900 and 4200 m a.s.l.). However, it is hypothesized that during the later part of the last glacial period and the early Holocene the plateau was extensively covered by Erica shrubs. Furthermore, it is assumed that the vegetation was later heavily destroyed by human-induced fire and/or climate change phenomena. The objective of this study is to contribute to paleovegetation reconstructions of the Sanetti Plateau by evaluating the potential of stable isotopes (δ13 C and δ15 N) and sugar biomarkers for distinguishing the dominant plant species, including Erica , and the soils below the plants. In a companion paper (Lemma et al., 2019a) we address the same issue by evaluating lignin-derived phenols and leaf-wax-derived n -alkane biomarkers. The stable carbon (δ13 C) and nitrogen (δ15 N) isotope values of the plant samples range from -27.5 ‰ to -23.9 ‰ and -4.8 ‰ to 5.1 ‰, respectively. We found no significant δ13 C and δ15 N differences between the dominant plant species. Mineral topsoils (A h horizons) yielded more positive values than plant samples and organic layers (O layers), which reflects mineralization processes. Moreover, the δ15 N values became generally more negative at higher altitudes. This likely indicates that the N cycle is more closed compared to lower altitudes. δ15 N maxima around 4000 m a.s.l. point to fire-induced opening of the N cycle at the chosen study sites. Erica species yielded the lowest overall total sugar concentration (ranging from 58 to 118 mg g -1), dominated by galactose (G) and mannose (M). By contrast, Festuca species revealed much higher total sugar concentrations ranging from 104 to 253 mg g -1 , dominated by the pentose sugars arabinose (A) and xylose (X). Although a differentiation between Erica versus Festuca, Alchemilla and Helichrysum is possible based on (G + M) / (A + X) ratios, Erica cannot be unambiguously distinguished from all other plant species occurring on the Sanetti Plateau. In addition, plant-characteristic (G + M) / (A + X) sugar patterns change during soil organic matter formation in the A h horizons. This can be likely attributed to degradation effects and soil microbial build-up of galactose and mannose. In conclusion, soil degradation processes seem to render sugar biomarker proxies unusable for the reconstruction of the past extent of Erica on the Sanetti Plateau, Bale Mountains, Ethiopia. This finding is of relevance beyond our case study. Kurzfassung: Das Sanetti Plateau in den Bale Bergen Äthiopiens ist in seinen höheren Lagen (zwischen 3900 und 4200 m ü. NN) durch das fragmentarische Vorkommen von Erica geprägt. Möglicherweise kam Erica während des Spätglazials und dem Frühholozän dagegen flächendeckend auf dem Plateau vor und wurde erst im Laufe des Holozäns durch Klimaveränderungen und menschlich verursachte Feuer zurückgedrängt. Das Ziel unserer Studie war es herauszufinden, ob sich die im Untersuchungsgebiet dominant vorkommenden Pflanzenarten einschließlich Erica und die sich unter der jeweiligen Vegetation entwickelten Böden anhand ihrer Stabilkohlenstoff- und Stickstoffisotopien (δ13 C und δ15 N) sowie ihrer Zucker-Biomarkermuster chemotaxonomisch unterscheiden lassen. In einem Begleitartikel (Lemma et al., 2019a) verfolgen wir dasselbe Ziel anhand von Lignin-bürtigen Phenolen und Blattwachs-bürtigen n -Alkan-Biomarkern. Die δ13 C und δ15 N-Werte für die untersuchten Pflanzen reichen von -27,5 ‰ bis -23,9 ‰ bzw. von -4,8 ‰ bis +5,1 ‰ und weisen keine signifikanten Unterschiede zwischen den dominanten Pflanzenarten auf. Positivere δ13 C und δ15 N-Werte in den A h Horizonten im Vergleich zu den Pflanzenproben und O-Lagen lassen sich mit der Mineralisations-bedingten Anreicherung von 13 C und 15 N in Böden erklären. Tendenziell negativere δ15 N-Werte mit zunehmender Höhe spiegeln vermutlich wider, dass der N-Kreislauf klimatisch bedingt in größeren Höhen zunehmend geschlossen ist. Lokale δ15 N Maxima in etwa 4000 m Höhe können sehr gut mit der hier feuerbedingten Öffnung des N-Kreislaufs erklärt werden. Erica weist mit 58 bis 118 mg g -1 die niedrigsten Zucker-Konzentrationen auf; es dominieren die Zucker Galactose und Mannose (G und M). Im Gegensatz dazu variieren die Zucker-Konzentrationen im weit verbreitet vorkommenden Gras der Gattung Festuca zwischen 104 und 253 mg g -1 ; hier dominieren die Zucker Arabinose und Xylose (A und X). Obwohl Erica anhand des (G + M) / (A + X) Verhältnisses von Festuca , Alchemilla und Helichrysum chemotaxonomisch unterschieden werden kann, gilt dies nicht für weitere untersuchte Pflanzenarten wie Kniphofia und Lobelia. Darüber hinaus offenbaren die Datenreihen Pflanze – O-Lage – A h -Horizont, dass die zum Teil pflanzencharakteristischen (G + M) / (A + X) Verhältnisse systematischen Veränderungen unterliegen. Dies kann vermutlich auf Degradation und den bodenmikrobiellen Aufbau von Galaktose und Mannose zurückgeführt werden und legt nahe, dass weder anhand von δ13 C und δ15 N, noch anhand von Zuckerbiomarkern eine verlässliche Rekonstruktion der Vegetation auf dem Sanetti Plateau möglich ist. [ABSTRACT FROM AUTHOR]

Erica is a dominant vegetation type in many sub-afroalpine ecosystems, such as the Bale Mountains in Ethiopia. However, the past extent of Erica is not well known and climate versus anthropogenic influence on altitudinal shifts are difficult to assign unambiguously, especially during the Holocene. The main objective of the present study is to chemotaxonomically characterize the dominant plant species occurring in the Bale Mountains using lignin phenols and n -alkane biomarkers and to examine the potential of those biomarkers for reconstructing vegetation history. Fresh plant material, organic layer and mineral topsoil samples were collected along a northeastern and a southwestern altitudinal transect (4134–3870 and 4377–2550 m a.s.l., respectively). Lignin-derived vanillyl, syringyl and cinnamyl phenols were analyzed using the cupric oxide oxidation method. Leaf-wax-derived n -alkanes were extracted and purified using Soxhlet and aminopropyl columns. Individual lignin phenols and n -alkanes were separated by gas-chromatography and detected by mass spectrometry and flame ionization detection, respectively. We found that the relative contributions of vanillyl, syringyl and cinnamyl phenols allow us to chemotaxonomically distinguish contemporary plant species of the Bale Mountains. Erica in particular is characterized by relatively high cinnamyl contributions of >40 %. However, litter degradation strongly decreases the lignin phenol concentrations and completely changes the lignin phenol patterns. Relative cinnamyl contributions in soils under Erica were <40 %, while soils that developed under Poaceae (Festuca abyssinica) exhibited relative cinnamyl contributions of >40 %. Similarly, long-chain n -alkanes extracted from the leaf waxes allowed for differentiation between Erica versus Festuca abyssinica and Alchemilla , based on lower C 31 / C 29 ratios in Erica. However, this characteristic plant pattern was also lost due to degradation in the respective O layers and A h horizons. In conclusion, although in modern-day plant samples a chemotaxonomic differentiation is possible, soil degradation processes seem to render the proxies unusable for the reconstruction of the past extent of Erica on the Sanetti Plateau, Bale Mountains, Ethiopia. This finding is of high relevance beyond our case study. Kurzfassung: Erica prägt als dominante Pflanzengattung viele Subafro-alpine Ökosysteme, so auch die Bale Berge in Äthiopien. Das Ausmaß der flächenhaften Ausdehnung von Erica in der Vergangenheit ist jedoch unklar, genauso wie die klimatische versus menschliche Verursachung solcher Vegetationsänderungen insbesondere im Holozän. Das Ziel dieser Studie war es herauszufinden (i) ob sich die dominante Vegetation in den Bale Bergen anhand von ligninbürtigen Phenolen und blattwachsbürtigen n -Alkanbiomarkern chemotaxonomisch unterscheiden lässt und (ii) ob diese Biomarker das Potential haben zur Vegetationsrekonstruktion im Untersuchungsgebiet beizutragen. In einem Begleitartikel (Mekonnen et al., 2019) verfolgen wir dasselbe Ziel, jedoch anhand von Stabilkohlenstoff- und Stickstoffisotopen sowie Zuckerbiomarkern. Untersucht wurden Pflanzenproben, O-Lagen und A h Horizonte entlang eines Nord- und eines Südwest-Höhentransektes (3870–4134 m bzw. 2550–4377 m ü. NN). Die ligninbürtigen Phenoleinheiten Vannilly, Syringyl und Cinnamyl wurden mittels der Kupferoxidationsmethode gewonnen; die n -Alkane wurden mittels Soxhlet extrahiert und über Aminopropylsäulen aufgereinigt. Die Quantifizierung der Ligninphenole und n -Alkane erfolgte mittels Gaschromatographie – Massenspektrometrie bzw. Gaschromatographie – Flammenionisationsdetektion. Die Ergebnisse zeigen, dass sich die dominanten Pflanzenarten in den Bale Bergen anhand ihrer Vanillyl, Syringyl und Cinnamyl Einheiten chemotaxonomisch unterscheiden lassen. So weist insbesondere Erica charakteristischerweise relativ hohe Cinnamyl-Anteile von >40 % auf. Vermutlich degradationsbedingt nimmt jedoch in der Reihe Pflanze – O-Lage – A h Horizont nicht nur die Ligninkonzentration stark ab, sondern auch die Ligninmuster ändern sich völlig. Dadurch weisen Böden unter Erica Cinnamyl-Anteile <40 % auf, während Böden die sich unter der dominanten Grasart Festuca abyssinica entwickelt haben Cinnamyl-Anteile von >40 % aufweisen. Auch anhand der Alkanbiomarker ist eine chemotaxonomische Unterscheidung zumindest zwischen Erica versus Festuca abyssinica und Alchemilla möglich. Als Proxy dient hier das Verhältnis von C 31 zu C 29. Allerdings führt auch hier Degradation in der Reihe Pflanze – O-Lage – A h Horizont zum Verlust des charakteristischen Alkanmusters. Obwohl sich rezentes Pflanzenmaterial chemotaxonomisch unterscheiden lässt, zwingt dies zur Schlussfolgerung, dass Degradationseffekte bei der Rekonstruktion von Erica im Untersuchungsgebiet der Bale Berge in Äthiopien anhand von ligninbürtigen Phenolen und blattwachsbürtigen Alkanbiomarkern nicht unberücksichtigt bleiben dürfen. Dieser Befund ist über unsere Fallstudie hinaus von hoher Relevanz. [ABSTRACT FROM AUTHOR]

Abstract: Species are often controlled by biotic factors such as competition at the warm edge of their distribution range. Disturbances at the treeline, disrupting competitive dominance, may thus enable alpine species to utilize lower altitudes. We searched for evidence for range expansion in grazed, fire‐managed Ethiopian subalpine Erica heathlands across a 25‐year chronosequence. We examined vascular plant composition in 48 plots (5 × 5 m) across an altitudinal range of 3,465–3,711 m.a.s.l. and analyzed how community composition changed in relation to increasing competition over time (using a Shade index based on Erica shrub height and cover) and altitude. Species‘ habitats and altitudinal ranges were derived from literature. Time since fire explained more variation (r2 = .41) in species composition than altitude did (r2 = .32) in an NMDS analysis. Community‐weighted altitudinal optima for species in a plot decreased strongly with increasing shade (GLM, Standardized Regression Coefficient SRC = −.41, p = .003), but increased only weakly with altitude (SRC = .26, p = .054). In other words, young stands were dominated by species with higher altitudinal optima than old stands. Forest species richness increased with Log Shade index (SRC = .12, p = .008), but was unaffected by altitude (SRC = −.07, p = .13). However, richness of alpine and heathland species was not highest in plots with lowest Shade index, but displayed a unimodal pattern with an initial increase, followed by a decrease when shading increased (altitude was not significant). Our results indicate that disturbance from the traditional patch burning increases the available habitat for less competitive high‐altitude plants and prevents tree line ascent. Therefore, maintaining, but regulating, the traditional land use increases the Afro‐alpine flora's resilience to global warming. However, this system is threatened by a new REDD+ program attempting to increase carbon storage via fire suppression. This study highlights the importance of understanding traditional management regimes for biodiversity conservation in cultural landscapes in an era of global change. [ABSTRACT FROM AUTHOR]

Background: Traditional management regimes and knowledge systems of forest resources have shaped forests throughout the world where materials from individual species are harvested in a sustainable manner. To comprehend this, the vegetation of Hugumburda-Gratkhassu Forest was described and related to anthropogenic factors. Methods: Three ethnobotanical research methods were used to collect indigenous knowledge of the local inhabitants related to conservation and utilization of forest resources. Direct matrix ranking was conducted to discover local attitudes on species preference for multiple use. During this work, the 46 most important tree and shrub species were selected based on recommendations of local guides and key informants to determine the range of uses obtained from each species. Through paired comparison, activities supposed to be the major cause of degradation of the forest were adopted. Pairs of activities were then established from the relation n (n-1)/2. Each respondent was then asked to select an activity that he considered being a major problem to management of the forest. Semi-structured interviews were used to obtain information from sixty local informants to address community attitudes towards forest management and utilization. Results: The result obtained from direct matrix ranking showed; that 20 out of 46 plant species compared had the highest scores and rank, indicating that these species are the most important and are exploited by the local communities for multiple purposes. The paired comparison exercise revealed logging for construction materials to be the major threat to the forest due to cutting of large volume of wood for construction of churches, health centers, schools and new houses. Juniperus procera, Olea europaea ssp. cuspidata, Rhus glutinosa, Flcus sur, Hagenla abysslnlca, Cassipourea malosana and Acacia etbaica were the most selected and exploited plant species for these purposes. Conclusions: Survival of protected areas depends on the support of local communities, rather than on fences, fines, or even force. The local communities in the study area have a rich indigenous ecological knowledge to suggest appropriate solutions for improvement of the forest resources. Thus the old tradition of isolating forests from the community has to be avoided and the basic needs and traditional rights of the communities over the uses of forest resources should be recognized. [ABSTRACT FROM AUTHOR]

One hundred and thirty-nine taxa of mosses are reported from the montane forest zone of southwest Ethiopia. Of these, 53 taxa are new country records andMeteoriopsis reclinata(Müll.Hal.) M.Fleisch.exBroth. is, in addition, new to Africa. Most of the new records are of species also found in Uganda, Kenya or Tanzania, but there are some surprises, such asFabronia perciliataMüll.Hal. with the closest location in South Africa and Namibia,Entodontella cameruniaeBroth. previously known only from West Africa andBryomaltaea obtusifolia(Hook.) Goffinet, otherwise reported only from the Democratic Republic of the Congo. We list all taxa and give a short account of their frequency and in which habitat and on which substrate they grow. That such a large proportion of the species are new to the country suggests that Ethiopia is bryologically very under-explored, and that further exploration will reveal many additional species. In particular, the remnant forests of southwest Ethiopia are likely to be of great importance as bryophyte hotspots. [ABSTRACT FROM PUBLISHER]

Aim Local extinction after habitat modifications is often delayed, leading to an extinction debt. Our first aim was to develop a conceptual model for natural and human-mediated habitat improvements after a disturbance that may waive part of the predicted extinction debt. Second, we wanted to test this model on the distribution of epiphytic plants on trees that had been isolated in the agricultural matrix after forest clearing, around which coffee subsequently had been planted with a possible improvement of the microclimate. Location Bonga, Southern Nations, Nationalities and Peoples Region (SNNPR), Ethiopia. Methods We studied 50 trees that had been isolated for periods ranging from a few years to half a century after clearing. The trees were now located in the agricultural landscape at different distances from intact Afromontane forests. Fourteen trees in the forests were used as references. Each tree was inventoried for all vascular epiphytic plants, mosses and liverworts. Results Time since clearance had a direct negative effect on number of forest specialist species via delayed extinctions and the detected large extinction debt of both bryophytes and vascular plants continued to be paid over several decades. However, time since clearance had an indirect positive effect on number of forest indicator species via the reappearance of shade from coffee planted surrounding the trees, even if the waiving effect on the extinction debt was rather small. Additionally, trees at further distances from the forest edge had fewer forest-associated species. Main conclusions Our results show that the ability of agroecological landscapes to foster forest biodiversity may be overestimated if meta-community processes over time and space are not taken into account. However, the possibility of initiating counteracting processes that modify the level of expected local extinctions should be evaluated more often to find ways of improving conditions for biodiversity in human-modified landscapes. [ABSTRACT FROM AUTHOR]

High tropical mountains harbour remarkable and fragmented biodiversity thought to a large degree to have been shaped by multiple dispersals of cold-adapted lineages from remote areas. Few dated phylogenetic/phylogeographic analyses are however available. Here, we address the hypotheses that the sub-Saharan African sweet vernal grasses have a dual colonization history and that lineages of independent origins have established secondary contact. We carried out rangewide sampling across the eastern African high mountains, inferred dated phylogenies from nuclear ribosomal and plastid DNA using Bayesian methods, and performed flow cytometry and AFLP (amplified fragment length polymorphism) analyses. We inferred a single Late Pliocene western Eurasian origin of the eastern African taxa, whose high-ploid populations in one mountain group formed a distinct phylogeographic group and carried plastids that diverged from those of the currently allopatric southern African lineage in the Mid- to Late Pleistocene. We show that Anthoxanthum has an intriguing history in sub-Saharan Africa, including Late Pliocene colonization from southeast and north, followed by secondary contact, hybridization, allopolyploidization and local extinction during one of the last glacial cycles. Our results add to a growing body of evidence showing that isolated tropical high mountain habitats have a dynamic recent history involving niche conservatism and recruitment from remote sources, repeated dispersals, diversification, hybridization and local extinction. [ABSTRACT FROM AUTHOR]

The scattered eastern African high mountains harbor a renowned and highly endemic flora, but the taxonomy and phylogeographic history of many plant groups are still insufficiently known. The high-alpine populations of the Geranium arabicum/kilimandscharicum complex present intricate morphological variation and have recently been suggested to comprise two new endemic taxa. Here we aim to contribute to a clarification of the taxonomy of these populations by analyzing genetic (AFLP) variation in range-wide high-alpine samples, and we address whether hybridization has contributed to taxonomic problems. We identified only two genetic groups. One corresponded to G. kilimandscharicum, which has been reported as exclusively high-alpine and confined to the eastern Rift mountains in East Africa. The other corresponded to G. arabicum, reported from lower altitudes on the same mountains as well as from a wide altitudinal span in Ethiopia and on the western Rift mountains in East Africa. The four populations analyzed of a recently described species from the Bale Mts in Ethiopia were admixed, indicating that they result from recent long-distance dispersal of G. kilimandscharicum from East Africa followed by hybridization with local G. arabicum in naturally disturbed habitats. Some admixture between the two genetic groups was also inferred on other mountains, supporting earlier suggestions of introgression based on morphology. We did not find support for recognition of the recently suggested new subspecies of G. arabicum in Ethiopia. Interestingly, the high-alpine G. kilimandscharicum lacked clear geographic structuring, suggesting a recent history of colonization of the different mountains or extensive intermountain gene flow. [ABSTRACT FROM AUTHOR]

The expansion of pollinator-dependent crops, especially in the developing world, together with reports of worldwide pollinator declines, raises concern of possible yield gaps. Farmers directly reliant on pollination services for food supply often live in regions where our knowledge of pollination services is poor. In a manipulative experiment replicated at 23 sites across an Ethiopian agricultural landscape, we found poor pollination services and severe pollen limitation in a common oil crop. With supplementary pollination, the yield increased on average by 91%. Despite the heterogeneous agricultural matrix, we found a low bee abundance, which may explain poor pollination services. The variation in pollen limitation was unrelated to surrounding forest cover, local bee richness and bee abundance. While practices that commonly increase pollinators (restricted pesticide use, flower strips) are an integral part of the landscape, these elements are apparently insufficient. Management to increase pollination services is therefore in need of urgent investigation. [ABSTRACT FROM AUTHOR]

Human population expansion and associated degradation of the habitat of many wildlife species cause loss of biodiversity and species extinctions. The small Simen Mountains National Park in Ethiopia is one of the last strongholds for the preservation of a number of afro-alpine mammals, plants and birds, and it is home to the rare endemic Walia ibex, Capra walie. The narrow distribution range of this species as well as potential competition for resources with livestock, especially with domestic goat, Capra hircus, may compromise its future survival. Based on a curated afro-alpine taxonomic reference library constructed for plant taxon identification, we investigated the diet of the Walia ibex and addressed the dietary overlap with domestic goat using DNA metabarcoding of faecal samples. Faeces of both species were collected from different localities in the National Park. We show that both species are browsers, with forbs, shrubs and trees comprising the largest proportion of their diet, supplemented by grasses. There was a considerable overlap in dietary preferences. Several of the preferred diet items of the Walia ibex (Alchemilla sp., Hypericum revolutum, Erica arborea and Rumex sp.) were also among the most preferred diet items of the domestic goat. These results indicate that there is potential for competition between the two species, especially during the dry season, when resources are limited. Our findings, in combination with the expected increase in domestic herbivores, suggest that management plans should consider the potential threat posed by domestic goats to ensure future survival of the endangered Walia ibex. [ABSTRACT FROM AUTHOR]

The flora on the isolated high African mountains or 'sky islands' is remarkable for its peculiar adaptations, local endemism and striking biogeographical connections to remote parts of the world. Ages of the plant lineages and the timing of their radiations have frequently been debated but remain contentious as there are few estimates based on explicit models and fossil-calibrated molecular clocks., We used the plastid region maturaseK ( matK) and a Caryophylloflora paleogenica fossil to infer the age of the genus Lychnis, and constructed a data set of three plastid ( matK; a ribosomal protein S16 ( rps16); and an intergenic spacer ( psbE-petL)) and two nuclear (internal transcribed spacer ( ITS) and a region spanning exon 18-24 in the second largest subunit of RNA polymerase II ( RPB2)) loci for joint estimation of the species tree and divergence time of the African representatives., The time of divergence of the African high-altitude Lychnis was placed in the late Miocene to early Pliocene. A single speciation event was inferred in the early Pliocene; subsequent speciation took place sporadically from the late Pliocene to the middle Pleistocene., We provide further support for a Eurasian origin of the African 'sky islands' floral elements, which seem to have been recruited via dispersals at different times: some old, as in Lychnis, and others very recent. We show that dispersal and diversification within Africa play an important role in shaping these isolated plant communities. [ABSTRACT FROM AUTHOR]

The naturally fragmented habitat on the tallest African mountains provides a good model system to study vicariance, dispersal, and hybridization. Many mountains are separated by lowland that likely was unsuitable for high-alpine plants even during cold climatic periods. We explore the relative importance of these processes using two endemic sister species: the widespread Ethiopian/eastern East African Carex monostachya and the mainly western East African C. runssoroensis. These bog-forming sedges co-occur in some mountains and are hypothesized to hybridize. The two species were distinctly differentiated for genome-wide amplified fragment length polymorphisms (AFLPs), also in one mountain where they co-occur. However, the plants from another mountain showed strong signals of admixture. The results suggest initial divergence into one western and one northern/eastern lineage, followed by long-distance dispersal resulting in secondary contact zones. In addition within species genetic diversity was clearly structured with distinct genetic groups on some, but not all mountains. Differentiation levels varied considerably and did not always correspond to the extent of lowland habitat between mountains. The narrow Rift Valley in the otherwise nearly contiguous highlands in Ethiopia appears to present a much stronger barrier to dispersal than the extensive lowlands separating Ethiopia from East Africa. This may be a general pattern since it has been documented also for other afro-alpine species. [ABSTRACT FROM AUTHOR]

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The major focus of ecological restorations has been on understanding local factors. However, landscape factors such as dispersal limitation of individuals or propagules across the surrounding matrix can also constrain the restoration progress. We investigated to what extent native woody species colonize and thrive in plantations, focusing on both the role of local factors such as grazing and canopy cover as well as on landscape factors. We recorded all native tree and shrub species in 60 small Eucalyptus plantations embedded in an open agricultural landscape at 0.1-12 km from a remnant continuous forest in central Ethiopia. We found a total of 1,571 individuals of native woody plants belonging to 55 species. Number of such species in a plantation increased significantly with the height of the grass sword indicating their sensitivity to grazing. Moreover, the number of woody species in the patches decreased significantly with distance to the forest. Our results illustrate the need for regulating the grazing pressure for a successful regeneration of native species in Eucalyptus plantations. In addition, sowing or planting native trees will be necessary in most plantations, as only few remnant natural forests that could act as seed sources occur across the Ethiopian highlands. Another main obstacle might be the prohibition of selling timber of native trees, which indirectly discourage farmers from letting native trees regenerate. Thus, the increasing cover of Eucalyptus seen across the country will not automatically foster a recovery of native woody plant biodiversity, even if managed to optimize local environmental conditions. [ABSTRACT FROM AUTHOR]

Mass-flowering plant species are often pollinated by social bees that are able to use the abundant resource by recruiting workers from their colonies. In this study we surveyed pollinators on the mass-flowering perennial crop coffee (Coffea arabica) in its native range in Ethiopia. Previous studies in areas where coffee is introduced often find the social honeybee, Apis mellifera, to be the dominant pollinator. In those areas, the bee-species composition visiting coffee varies with a higher bee diversity closer to forest or in less modified habitats. We surveyed pollinators of coffee under different shade-tree structures, by collecting hoverflies and bees landing on coffee flowers in 19 sites in south-west Ethiopia. We found the native honeybee (A. mellifera) to be the dominant visitor of coffee flowers in all sites. Honeybee abundance was not affected by the local shade-tree structure, but was positively affected by the amount of coffee flower resources. Other pollinators were positively affected by complex shade-tree structures. To conclude, the honeybee is clearly the dominant pollinator of coffee in Ethiopia along the whole shade-tree structure gradient. Its high abundance could be a consequence of the provision of traditional bee hives in the landscape, which are colonized by wild swarming honeybees. [ABSTRACT FROM PUBLISHER]

Shaded coffee has been highlighted for its potential to conserve biodiversity, and thus perhaps also a diversity of natural enemies that could control pest organisms. In southwestern Ethiopia, coffee is grown in shade both in contiguous forests and in forest patches with native trees surrounded by open fields. We hypothesized that coffee grown in contiguous forests, which is the natural habitat for coffee ( Coffea arabica) and its interacting organisms, would have less pest damage due to high protection by natural enemies. We surveyed pests on coffee plants in plots within contiguous forests (10 sites) and in forest patches (21 sites). In general, the variation in number of damaged or attacked leaves by individual insect or fungal pests was larger between plants than between plots, which suggests that very local conditions or processes are important. The spatial signals were generally weak. Coffee rust and coffee blotch miner tended to have lower infestation rates in accordance with our hypothesis, while fruit flies in ripe berries were more abundant in forest patches closer to contiguous forest. Based on interviews, olive baboons showed a clear dependency on contiguous forest habitat and were regarded as a problem only in contiguous forests and forest patches close to contiguous forests. In conclusion, we found no support for a generally stronger top-down control on coffee pests in sites within, or with connectivity to, contiguous moist afromontane forests in the native range of coffee. [ABSTRACT FROM AUTHOR]

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The flora on the afro-alpine sky islands is renowned for extreme fragmentation, representing a unique natural experiment in biogeography. Here we address the roles of isolation and gene flow, in particular across the narrow Rift Valley (the RV barrier) that cuts through the Ethiopian Highlands (EH), and across the vast low-lying landscape that separates EH from the East African mountains (the EH-EA barrier). We inferred the history of two species with different dispersal mechanisms, but with similar geographic ranges and habitats based on Amplified fragment length polymorphisms (AFLPs). Contrary to our predictions, we found that the populations from opposite sides of the RV barrier were less similar than those from opposite sides of the EH-EA barrier, and that only the supposedly short distance-dispersed species ( Trifolium cryptopodium) showed a strong signal of secondary gene flow across the RV barrier. In the wind-dispersed Carduus schimperi, we rather found an evidence for the gene flow between differentiated populations inhabiting different EA mountains. Both species harbored little genetic diversity but considerable genetic rarity in several individual mountains, suggesting long-term isolation and bottlenecks during climatically unfavorable periods. Our genetic data corroborate a division of C. schimperi into three subspecies, but with new delimitation of their ranges, and of T. cryptopodium into two intraspecific taxa. Our findings support the idea that stochasticity may play a major role in shaping extremely fragmented ecosystems such as the afro-alpine. After initial colonization of different mountains, periods of isolation may alternate with unpredictable episodes of intermountain gene flow. [ABSTRACT FROM AUTHOR]

Phylogeographic studies in the high mountains of Africa are hampered by the limited material available, resulting in insufficient knowledge of taxonomic variation within and among closely related species. Here, we address genetic and morphological variation in three grass species, of which one ( Deschampsia angusta) has been reported as narrowly endemic and vulnerable whereas Deschampsia cespitosa and Koeleria capensis are widely distributed also outside the afro-alpine region. We used amplified fragment length polymorphisms (AFLPs) to assess genetic structuring and diversity in material collected during recent field expeditions and included additional herbarium material in morphometric analyses. The plants identified as the endemic D. angusta were genetically very similar to those identified as D. cespitosa from the same mountain (Mt Ruwenzori), forming a single coherent genetic group in STRUCTURE analysis. The plants identified as D. angusta seem to represent extremes of continuous gradients of morphological variation within a single, variable species, D. cespitosa. We found that the afro-alpine material of Deschampsia consists of three genetically very distinct groups corresponding to the three mountains investigated, suggesting persistence in isolated afro-alpine refugia during one or more glacial cycles. In contrast, we found no clear genetic structure in K. capensis. This species harbored very little genetic diversity in all six mountain areas examined, and little genetic rarity except in the Ethiopian Simen Mts. This pattern may be explained by recent colonization of the afro-alpine region from a single source population or possibly by extensive recent gene flow combined with bottlenecks. We found, however, some differentiation between different K. capensis populations from Mt Kilimanjaro, corresponding to two described varieties. This study demonstrates the need for further taxonomic exploration of the enigmatic flora of the isolated afro-alpine 'sky islands' and highlights that different species may have conspicuously different phylogeographic histories. [ABSTRACT FROM AUTHOR]

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Of all feeding guilds, understorey insectivores are thought to be most sensitive to disturbance and forest conversion. We compared the composition of bird feeding guilds in tropical forest fragments with adjacent agro-ecosystems in a montane region of south-west Ethiopia. We used a series of point counts to survey birds in 19 agriculture and 19 forest sites and recorded tree species within each farm across an area of 40 × 35 km. Insectivores (~17 spp. per plot), frugivores (~3 spp. per plot) and omnivores (~5 spp. per plot) maintained species density across habitats, while granivores and nectarivores increased in the agricultural sites by factors of 7 and 3 respectively. Species accumulation curves of each guild were equal or steeper in agriculture, suggesting that agricultural and forest landscapes were equally heterogeneous for all bird guilds. Counter to most published studies, we found no decline in insectivore species richness with forest conversion. However, species composition differed between the two habitats, with certain forest specialists replaced by other species within each feeding guild. We suggest that the lack of difference in insectivorous species numbers between forest and agriculture in this region is due to the benign nature of the agricultural habitat, but also due to a regional species pool which contains many bird species which are adapted to open habitats. [ABSTRACT FROM PUBLISHER]

Floristic composition and vegetation structure were described for the woodland vegetation around Dello Menna, Bale zone, southeast Ethiopia. A total 50 (20 m × 20 m) quadrats were sampled to identify and describe plant community types, species diversity, richness and evenness and to relate the identified plant community types with some environmental factors and describe the population structure of woody plant species. In each quadrat, data on species identity, abundance, height and Diameter at Breast Height (DBH) of woody plant species, altitude and slope were recorded. Vegetation classification was performed using PC - ORD software package. Sorensen's similarity coefficient was used to detect dissimilarities among communities. Shannon - Wiener diversity index, species richness and Shannon's evenness were computed to describe species diversity of the plant community types. Results show that a total of 171 vascular plant species representing 53 families were recorded. Fabaceae is the dominant family represented by 13 genera and 26 species (15%) followed by Asteraceae, Lamiaceae and Anacardiaceae with eight species each (4.6%). Based on the results of vegetation classification, three plant communities ( Dalbergia microphylla community, Grewia bicolar- Acacia brevispica community, and Combretum molle-Combretum collinum community) are recognized and described. Species richness, diversity and evenness varied among the plant communities. Species richness and diversity exhibit a bell - shaped pattern along altitude. Species turn over among communities more or less follow altitudinal gradients. Tukey's pairwise comparison of means among the plant community types shows significant variations in altitude, implying that altitude is one of the most important factors determining the distribution of plant communities. The community Dalbergia microphylla type exhibits the highest species richness and diversity. Analysis of population structure of the dominant species reveals various patterns. Future research directions and recommendations are suggested for the sustainable utilization of the vegetation. [ABSTRACT FROM AUTHOR]

Ethiopia has diverse topographic features and climatic conditions with a diverse flora. The liverwort flora of southwest Ethiopia is practically unknown, despite a favourable climate and the occurrence of suitable ecosystems such as montane rainforests. During an ecological study of diversity patterns of bryophytes and vascular plants in relation to land use, we recorded many bryophyte species. In this paper we report the finding of 89 species of liverworts, and give short ecological notes and describe the distribution (locally and in Africa) for each species. Of these, 51 species are newly reported from Ethiopia. It is thus obvious that Ethiopia is considerably richer in liverworts than might be expected from previous checklists. [ABSTRACT FROM AUTHOR]