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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 (r 2  = .41) in species composition than altitude did (r 2  = .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., (© 2018 John Wiley & Sons Ltd.)

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]

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]

Distributions of potential ranges of plant species are not yet fully known in Ethiopia where high climatic variability and vegetation types are found. This study was undertaken to predict distributions of suitable habitats of Pouteria adolfi‐friederici and Prunus africana under current and two future climate scenarios (RCP 4.5 and RCP 8.5 in 2050 and 2070) in Ethiopia. Eleven environmental variables with less correlation coefficients (r < 0.7) were used to make the prediction. Shifting in extents of habitat suitability and effects of elevation, solar radiation and topographic position in relation to the current and future climatic scenarios were statistically analysed using independent t‐test and linear model. We found decreasing area of highly suitable habitat from 0.51% to 0.46%, 0.36% and 0.33%, 0.24% for Prunus africana and 1.13% to 1.02%, 0.77% and 0.76%, 0.60% for Pouteria adolfi‐friederici, under RCP 4.5 and RCP 8.5 by 2050 and 2070 respectively. Moist and dry afromontane forests are identified as the most suitable habitat for both species. Overall, our results suggest that climate change can promote dynamic suitable habitat niches under different future climate scenarios. Therefore, biodiversity conservation strategies should take into account habitat suitability dynamics issues and identify where to conserve species before implementing conservation practices. [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]

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]

In wide-ranging species, the genetic consequences of range shifts in response to climate change during the Pleistocene can be predicted to differ among different parts of the distribution area. We used amplified fragment length polymorphism data to compare the genetic structure of Arabis alpina, a widespread arctic-alpine and afro-alpine plant, in three distinct parts of its range: the North Atlantic region, which was recolonized after the last ice age, the European Alps, where range shifts were probably primarily altitudinal, and the high mountains of East Africa, where the contemporary mountain top populations result from range contraction. Genetic structure was inferred using clustering analyses and estimates of genetic diversity within and between populations. There was virtually no diversity in the vast North Atlantic region, which was probably recolonized from a single refugial population, possibly located between the Alps and the northern ice sheets. In the European mountains, genetic diversity was high and distinct genetic groups had a patchy and sometimes disjunct distribution. In the African mountains, genetic diversity was high, clearly structured and partially in accordance with a previous chloroplast phylogeography. The fragmented structure in the European and African mountains indicated that A. alpina disperses little among established populations. Occasional long-distance dispersal events were, however, suggested in all regions. The lack of genetic diversity in the north may be explained by leading-edge colonization by this pioneer plant in glacier forelands, closely following the retracting glaciers. Overall, the genetic structure observed corresponded to the expectations based on the environmental history of the different regions. [ABSTRACT FROM AUTHOR]

Species tend to shift their suitable habitat both altitudinally and latitudinally under climate change. Range shift in plants brings about habitat contraction at rear edges, forcing leading edge populations to explore newly available suitable habitats. In order to detect these scenarios, modeling of the future geographical distribution of the species is widely used. Vachellia negrii (Pic.-Serm.) Kyal. & Boatwr. is endemic to Ethiopia and was assessed as vulnerable due to changes to its habitat by anthropogenic impacts. It occurs in upland wooded grassland from 2000–3100 m.a.s.l. The main objective of this study is to model the distribution of Vachellia negrii in Ethiopia by using Maxent under climate change. Nineteen bioclimatic variables were downloaded from an open source. Furthermore, topographic position index (tpi), solar radiation index (sri) and elevation were used. Two representative concentration pathways were selected (RCP 4.5 and RC P8.5) for the years 2050 and 2070 using the Community Climate System Model (CCSM 5). A correlation analysis of the bioclimatic variables has resulted in the retention of 10 bioclimatic variables for modeling. Forty-eight occurrence points were collected from herbarium specimens. The area under curve (AUC) is 0.94, indicating a high-performance level of the model. The distribution of the species is affected by elevation (26.4%), precipitation of the driest month (Bio 14, 21.7%), solar radiation (12.9%) and precipitation seasonality (Bio15, 12.2%). Whereas the RCP 8.5 has resulted in decrease of suitable areas of the species from the current 4,314,153.94 ha (3.80%) to 4,059,150.90 ha (3.58%) in 2050, this area will shrink to 3,555,828.71 ha in 2070 under the same scenario. As climate change severely affects the environment, highly suitable areas for the growth of the study subject will decrease by 758,325 ha. The study's results shows that this vulnerable, endemic species is facing habitat contraction and requires interventions to ensure its long-term persistence. [ABSTRACT FROM AUTHOR]