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Context: Deforestation, forest degradation and intensification of farming threaten terrestrial biodiversity. As these land-use changes accelerate in many landscapes, especially in the Global South, it is vital to anticipate how future changes might impact specific aspects of biodiversity. Objectives: The objectives of this study were to model woody plant species richness in southwestern Ethiopia, for the present and for four plausible, spatially explicit scenarios of the future ('Gain over grain', 'Mining green gold', 'Coffee and conservation' and 'Food first'). Methods: We used cross-validated generalized linear models for both forest and farmland, to relate empirical data on total and forest-specialist woody plant species richness to indicators of human disturbance and environmental conditions. We projected these across current and future scenario landscapes. Results: In both farmland and forest, richness peaked at intermediate elevations (except for total species richness in farmland) and decreased with distance to the forest edge (except for forest specialist richness in forest). Our results indicate that the 'Mining green gold' and 'Food first' scenarios would result in strong losses of biodiversity, whereas the 'Gain over grain' scenario largely maintained biodiversity relative to the baseline. Only the 'Coffee and conservation' scenario, which incorporates a new biosphere reserve, showed positive changes for biodiversity that are likely viable in the long term. Conclusions: The creation of a biosphere reserve could maintain and improve woody plant richness in the focal region, by forming a cluster with existing reserves, would be a major step forward for sustainability in southwestern Ethiopia. [ABSTRACT FROM AUTHOR]

This study examines species composition, diversity and plant community distribution along environmental gradients of Tulu Lafto Forest (here after called TLF) in Horo Guduru Wollega Zone of Oromia National Regional State, western Ethiopia. Seventy-five quadrats of 400 m2 were systematically laid following altitudinal gradient. A complete list of trees, shrubs, lianas and herbs including vascular epiphytes were made from each quadrat. Environmental variables including soil samples were collected, recorded and analyzed for each quadrat. In the forest, 230 plant species belonging to 188 genera and 79 families were identified. Out of these, 16 species are endemic to the flora of Ethiopia and Eritrea and 56 were new records for Wollega (WG) floristic region. Asteraceae and Fabaceae are the top species rich plant families. Cluster analysis and ordination methods identified 3 plant community types mainly influenced by topographic, edaphic and anthropogenic factors. TLF exhibited an intermediate A fromontane type suggesting the need to revise the existing vegetation classification in the country. [ABSTRACT FROM AUTHOR]

Vegetation-environment relationships are usually studied along elevational gradient. The patterns of plant community distribution in Gole forest, Ethiopia, were studied along elevational gradient and disturbances. Disturbances were recorded following the elevational gradient. For vegetation data collection, 62 sample plots of size 20 × 20 m were established along an elevational gradient (2728–3480 m.a.s.l). Data on species composition and environmental variables were measured and recorded in each plot. The elevation of each sample plot was measured using Garmin GPS. Anthropogenic disturbances in each plot were estimated using the following scales: 0 = no disturbance, 1 = slightly disturbed, 2 = moderately disturbed, and 3 = highly disturbed. R statistical package was used for cluster and ordination analysis. Boxplots and analysis of variance were used to assess the relationships between plant communities and environmental variables. Sorensen's similarity coefficient was used to detect similarities and dissimilarities among communities. A total of 114 plant species belonging to 57 families and 94 genera were identified. Five plant community types were identified using agglomerative hierarchical cluster analysis. Every plant community had differences in composition and environmental variables. The variation in plant community distributions was significantly related to elevation and disturbance. Plant community distribution was negatively correlated with elevation (P < 0.05) and also with disturbance (P < 0.05). Sorensen's similarity index showed that there was a difference in the distribution of plant species composition among the communities. The difference in plant community distribution of Gole forest was significantly related to elevation. Disturbances also have a considerable influence on the plant communities and mitigation of disturbance should be the main measure that needs to be taken into account in conservation planning in the study area. [ABSTRACT FROM AUTHOR]

For forest ecosystem management to be effective, explicit understanding of the species diversity-environmental relationship along elevation gradient is crucial. This study aimed at identifying and describing plant communities and also documenting their species diversity. Evaluation of relationships between selected environmental variables and species diversity was another objective of this study. Systematic sampling techniques were used to collect vegetation data in a total of forty two sample plots (size=20×20 m). Within main plots, four sub-plots of 5×5 m were established at four corners and – one sub-plot of the same size in the center. These plots were used for shrub and herb diversity assessment. Within each sample plot, all plant species were documented and their scientific names were identified. Environmental variables, such as: elevation, aspect and slope, were also recorded for each main plot. Species diversity was determined using Shannon-Wiener diversity index and evenness in R statistical software. Agglomerative hierarchical clustering method was used for plant community classification. The total of 44 plant species belonging to 30 families was documented. Four plant community types were identified with different diversity, evenness and species richness. These plant communities were: Afrocurpus falcatus-Ficus sur, Maesa lanceolata-Bersama abyssinica, Vernonia myriantha-Urera hypselodendron and Croton machrostachus-Tecleanobilis occurring at average elevation of 2521, 2429, 2329, and 2364 m asl, respectively. Maesa lanceolata-Bersama abyssinica community type exhibited the highest species diversity and evenness followed by Croton machrostachus-Teclea nobilis community type showing the fact that median elevation ranges were rich in species. Elevation and slope gradient explained significant variation in species richness in the studied forest. For effective conservation of biodiversity and sustainable management of the forest ecosystem, further research on the impacts of anthropogenic disturbances and soil properties is recommended as a result of this study. [ABSTRACT FROM AUTHOR]

Introduction: Climate change will either improve, reduce, or shift its appropriate climatic habitat of a particular species, which could result in shifts from its geographical range. Predicting the potential distribution through MaxEnt modeling has been developed as an appropriate tool for assessing habitat distribution and resource conservation to protect bamboo species. Methods: Our objective is to model the current and future distribution of Oxytenanthera abyssinica (A. Richard) based on three representative concentration pathways (RCP) (RCP2.6, RCP4.5, and RCP8.5) for 2050s and 2070s using a maximum entropy model (MaxEnt) in Northern Ethiopia. For modeling procedure, 77 occurrence records and 11 variables were retained to simulate the current and future distributions of Oxytenanthera abyssinica in Northern Ethiopia. To evaluate the performance of the model, the area under the receiver operating characteristic (ROC) curve (AUC) was used. Results: All of the AUCs (area under curves) were greater than 0.900, thereby placing these models in the "excellent" category. The jackknife test also showed that precipitation of the coldest quarter (Bio19) and precipitation of the warmest quarter (Bio18) contributed 66.8% and 54.7% to the model. From the area of current distribution, 1367.51 km2 (2.52%), 7226.28 km2 (13.29%), and 5377.26 km2 (9.89%) of the study area were recognized as high, good, and moderate potential habitats of Oxytenanthera abyssinica in Northern Ethiopia, and the high potential area was mainly concentrated in Tanqua Abergele (0.70%), Kola Temben (0.65%), Tselemti (0.60%), and Tsegede (0.31%). Kafta Humera was also the largest good potential area, which accounts for 2.75%. Compared to the current distribution, the total area of the high potential regions and good potential regions for Oxytenanthera abyssinica under the three RCPs (RCP2.6, RCP4.5, and RCP8.5) would increase in the 2050s and 2070s. However, the total area of the least potential regions under the three RCPs (RCP2.6, RCP4.5, and RCP8.5) in 2050s and 2070s would decrease. Conclusion: This study can provide vital information for the protection, management, and sustainable use of Oxytenanthera abyssinica, the resource to address the global climate challenges. [ABSTRACT FROM AUTHOR]

Abstract: Aim: Past land use legacy effects—extinction debts and immigration credits—might be particularly pronounced in regions characterized by complex and dynamic landscape change. The aim of this study was to evaluate how current woody plant species distribution, composition and richness related to historical and present land uses. Location: A smallholder farming landscape in south‐western Ethiopia. Methods: We surveyed woody plants in 72 randomly selected 1‐ha sites in farmland and grouped them into forest specialist, generalist and pioneer species. First, we investigated woody plant composition and distribution using non‐metric multidimensional scaling. Second, we modelled species richness in response to historical and current distance from the forest edge. Third, we examined diameter class distributions of trees in recently converted vs. permanent farmland. Results: Historical distance was a primary driver of woody plant composition and distribution. Generalist and pioneer species richness increased with historical distance. Forest specialists, however, did not respond to historical distance. Only few old individuals of forest specialist species remained in both recently converted and permanent farmlands. Main conclusions: Our findings suggest that any possible extinction debt for forest specialist species in farmland at the landscape scale was rapidly paid off, possibly because farmers cleared large remnant trees. In contrast, we found substantial evidence of immigration credits in farmland for generalist and pioneer species. This suggests that long‐established farmland may have unrecognized conservation values, although apparently not for forest specialist species. We suggest that conservation policies in south‐western Ethiopia should recognize not only forests, but also the complementary value of the agricultural mosaic—similar to the case of European cultural landscapes. A possible future priority could be to better reintegrate forest species in the farmland mosaic. [ABSTRACT FROM AUTHOR]

This study was aimed to establish the elemental profiling and provenance of coffee samples collected from eleven major coffee producing regions of Ethiopia. A total of 129 samples were analyzed for forty-five elements using inductively coupled plasma (ICP)-optical emission spectroscopy (OES), ICP-mass spectrometry (MS) and direct mercury analyzer (DMA). Among the macro elements, K showed the highest levels whereas Fe was found to have the lowest concentration values. In all the samples, Ca, K, Mg, P and S contents were statistically significant ( p < 0.05). Micro elements showed the concentrations order of: Mn > Cu > Sr > Zn > Rb > Ni > B. Contents of the trace elements were lower than the permissible standard values. Inter-regions differentiation by cluster analysis (CA), linear discriminant analysis (LDA) and principal component analysis (PCA) showed that micro and trace elements are the best chemical descriptors of the analyzed coffee samples. [ABSTRACT FROM AUTHOR]

We studied the diversity, community composition and natural regeneration of woody species in an isolated but relatively large (> 1,000 ha) dry Afromontane forest in northern Ethiopia to assess its importance for regional forest biodiversity conservation. The principal human-induced disturbance regimes affecting this forest include logging and livestock grazing. Vegetation data were collected in 65 plots (50 m × 50 m); seedling species composition and density were determined in 10 m × 10 m nested plots. We used a cluster analysis to identify plant communities and non-metric multidimensional scaling (NMDS) ordination to investigate environmental factors that influenced the distribution of the emergent plant communities. Three plant communities were identified: a Juniperus procera-Maytenus senegalensis community, which represented a phase of the potential natural dry Afromontane forest vegetation on steep slopes with shallow soils, a Pterolobium stellatum-Celtis africana community, found on more mesic sites, and a Cadia purpurea-Opuntia ficus-indica community, typically representing severely disturbed habitats. Altitude, slope, soil depth and distance to the nearest stream, which we collectively interpreted as a moisture gradient, and forest disturbance separated the plant communities. With only 39 of the 79 recorded woody species present in the seedling layer, the forest currently faces an extinction debt of 50 per cent of the total woody species pool. Human disturbance has clearly affected plant species diversity in this forest as degraded plant communities typically lacked the commercially interesting or otherwise valuable tree species, were encroached by shrubs and in areas severely invaded by alien species. Further disturbance will most likely result in additional declines in biodiversity through local extinction of indigenous tree species. Despite the problems associated with conserving plant species diversity in small and isolated populations, this relic forest is of particular importance for regional conservation of forest biodiversity, as species with high conservation value, such as Afrocarpus falcatus, Allophylus abyssinicus and Bersama abyssinica, are still present as mature trees, and as other forest fragments in the region are two orders of magnitude smaller, and therefore more heavily impacted by small population sizes and unfavourable edge effects. Forest management should focus on avoiding further degradation, increasing natural regeneration and improving stakeholder participation. [ABSTRACT FROM AUTHOR]

Question Evergreen bushlands in Ethiopia have been inadequately studied and mapped. We address the question whether there is a transitional semi-evergreen bushland on the eastern escarpment of the Ethiopian Highlands, with unique floristic characteristics that distinguish it from the evergreen bushlands in other parts of Ethiopia and eastern Africa. Methods Based on a review of the recent descriptions of evergreen bushlands in Ethiopia, we hypothesize that there is a distinct zone of natural semi-evergreen bushland, which is restricted to the eastern and southeastern escarpment of the Ethiopian Highlands. In contrast, evergreen bushlands in other parts of Ethiopia are considered to be of a secondary nature. To test this hypothesis, we carried out qualitative vegetation surveys in 354 locations across Ethiopia and classified the vegetation in these locations based on the occurrences of indicator species. Based on this data, we created predictive distribution models of the semi-evergreen bushland in Ethiopia using various environmental distribution models. We furthermore compared the occurrences of characteristic evergreen bushland species in Ethiopia with the occurrence of these species within the evergreen bushlands in Kenya and Uganda. Results The vegetation surveys confirmed the existence of a distinct type of evergreen bushland vegetation. The transitional semi-evergreen bushland forms a transitional zone between the Acacia- Commiphora woodland and bushland and the Afromontane forest on the eastern and southeastern escarpments of Ethiopia, but is also characterized by a number of species that, within Ethiopia, are unique to this zone. Most of the characteristic species of the transitional semi-evergreen bushland are not found or only in lower densities in western Ethiopia. There is, furthermore, a limited overlap in characteristic species of the evergreen bushlands of Kenya and Uganda. Conclusions Our results provide important information on the hitherto inadequately studied semi-evergreen bushland of Ethiopia. It highlights the unique character of this part of the evergreen bushlands in Ethiopia, which we argue should be taken into account for future conservation planning. [ABSTRACT FROM AUTHOR]

Forests of SW Ethiopia constitute the native habitat of Coffea arabica and also the place where domestication of Arabica coffee started. Selection from wild populations has led to numerous landraces (farmer's varieties) and cultivars. Inter-simple sequence repeats (ISSRs) were generated from a representative set of forest coffee populations and landraces across Ethiopia. For the broad diversity assessment, nine di- and tri-nucleotide ISSR primers were applied, as chosen from a total of 102 primers tested initially. Tetranucleotide ISSR primers differed in amplifying fingerprints that could hardly be analysed due to excessive variation. Tree building analysis (NJ, UPGMA) of 84 polymorphic loci amplified for 125 C. arabica individuals provided evidence for several groups of related genotypes occurring in certain geographical areas of Ethiopia and underscored the existence of wild coffee distinct from landraces. Landraces seem to have originated in different geographical areas of Ethiopia in a stepwise domestication process. While the overall geographical signal in the dataset was weak, analysis in a Bayesian framework using the admixture model with geographical priors in STRUCTURE recovered some genetic clustering. Based on Shannon's diversity index, populations from Yayu (0.47) and Bonga (0.46) showed highest diversity, followed by individuals from Berhane Kontir (0.41). A likely scenario for the differentiation of C. arabica after an allopolyploidization event is that the hierarchical-geographical patterning of wild Coffea genotypes expected from stepwise range extension was obscured by recent or ancient gene flow. The diversity and geographical distribution of autochthonous C. arabica genotypes indicates the need for a multi-site in situ conservation approach. [ABSTRACT FROM AUTHOR]

Extensive studies of genetic diversity and population structure important for conservation of wild sorghum are yet lacking in Ethiopia, the centre of origin for cultivated sorghum. To assess both genetic diversity and the probability of gene flow between wild and cultivated types, collections of wild Sorghum bicolor were made from regions in Ethiopia where wild and cultivated sorghum coexist. Morphological data were recorded in situ for both quantitative and qualitative characters from 30 populations in five diverse geographical regions and eight agroecologies. High phenotypic diversity was observed among the wild and weedy sorghum populations. The overall standardized Shannon–Weaver diversity index (H′), computed from the frequencies of all qualitative traits, ranged from 0.47 to 0.98 with an average value of 0.76. Moreover, warm semi-arid lowland (SA2) agroecologies, which contain Tigray populations, supported the highest diversity for these traits. Subspecies verticilliflorum and drummondii (the two major subspecies of wild S. bicolor) were observed in diverse habitats throughout northern and central Ethiopia. In some areas, weedy types showed domestication traits including the absence of awns and reduced seed shattering. The existence of morphologically intermediate forms indicates that gene flow between cultivated and wild forms has likely occurred. Deployment of transgenic crop sorghum, therefore, would pose a distinct risk for transgene movement into wild Ethiopian populations. [ABSTRACT FROM AUTHOR]

Striga hermonthica, a root hemiparasitic Orobanchaceae, severely constrains grain production in sub-Saharan Africa. Host specificity and geography may play important roles in shaping the population structure of S. hermonthica, with the Rift Valley potentially presenting a significant barrier to dispersal. Genetic diversity was assessed in 12 S. hermonthica populations from locations in Ethiopia. Of these, seven populations were parasitic on sorghum, two each on tef and maize, and one on finger millet. Genetic variation was detected using four amplified fragment length polymorphism (AFLP) primer combinations. After correcting for repeatability, 385 fragments were detected across all primer combinations. The percentage of polymorphic loci was relatively high, ranging from 53.2% to 76.4%. Expected heterozygosity ranged from 0.168 to 0.279. Genetic differentiation between populations was relatively high, and all populations were significantly different from each other . FST values ranged from 0.032 to 0.293 and averaged 0.146. Genetic differences between populations could not be attributed to host specificity. Instead, geography was the main determinant of population structure. There was a correlation between geographic and genetic distance. A significant portion of the genetic variance could be apportioned on either side of the Rift Valley (5%; P = 0:001). Also, a significant geographic barrier was identified in the southern portion of the sampled region. [ABSTRACT FROM AUTHOR]

Abstract: Regeneration of seven indigenous tree species having significant ecological and economic importance was investigated in the Munessa-Shashemene dry Afromontane forest (MSF), southern Ethiopia. Densities and distributions of seedlings, saplings and trees were assessed along gradients of altitude, light and disturbance using quadrat sizes of 10×5m (for seedlings) and 20×20m (saplings and trees) following line transects. The number of individuals, frequency and height of the study species were recorded in the quadrats at every 100m drop in altitude. Seedling densities varied markedly among the species and altitudes. Mean densities (number of individuals ha−1) of seedlings ranged from zero (Polyscias fulva) to 5334 (Prunus africana), and from three (Polyscias fulva) to 102 (Podocarpus falcatus) for trees and saplings. Canonical Correspondence Analysis revealed that seedlings of Celtis africana and Croton macrostachyus were highly favored by disturbance and, hence, were concentrated in canopy gaps within the forest. Based on their population structures, the study species could be categorized into three groups: (1) Species that showed the highest proportion of individuals in the lowest height class and with a gradual decrease towards the upper height classes, which suggests good regeneration; Podocarpus falcatus, C. africana, C. macrostachys and P. africana belonged to this group. (2) Species that showed higher proportions of individuals in the lowest height class and with missing individuals in the subsequent middle height classes, indicative of hampered regeneration; Syzygium guineense and Pouteria adolfi-friederici belonged to this group. (3) Species with no individuals in the lowest and middle height classes but represented by individuals in upper height classes; P. fulva belonged to this group. The species categorized in the last two groups exhibited hampered regeneration, and P. fulva is in the verge of local extermination. High seedling densities (e.g. C. africana and P. africana) and/or adaptive defense mechanisms to herbivory (e.g. P. falcatus and C. macrostachyus) were common attributes of species, which exhibited good regeneration. Regeneration problems were largely attributed to human disturbance, lack of suitable habitat for seed germination or problems associated to seed set (seed predation or abortion). Our study indicated that P. fulva, P. adolfi-friederici and S. guineense require the highest immediate attention for conservation in the MSF. [Copyright &y& Elsevier]

Abstract: Fossil pollen grains extracted from sediments sampled from OGS-6a and OGS-7, two newly excavated Late Pliocene sites of Gona, in the Afar Depression of Ethiopia, indicate a high percentage of afromontane forest and highland taxa (36.8–43.3%), among which Podocarpus cf. gracilor is dominant (19.6–24.2%). Forest taxa typical of the afromontane phytogeographic region have also been identified in the samples. The overall pollen spectrum suggests a mosaic of open and closed habitats, with a considerable wooded environment present during the time associated with the beginnings of early hominid use of flaked stones at Gona. Here we provide details of the results from the pollen analyses. The two sites lie 4–8 m directly below a volcanic tuff dated by 40Ar/39Ar to 2.53±0.15 million years (Ma). The materials were recovered within fine-grained sediments located just above a geomagnetic polarity transition identified as the Gauss-Matuyama boundary dated close to 2.6 Ma, also corroborating the earlier age reported for the East Gona artifacts from EG-10 and EG-12. Thus, the stone artifacts, fossilized broken fauna and pollen grains from OGS-6a and OGS-7 represent archaeological materials from the world''s oldest securely dated sites, and offer insights on aspects of the palaeoenvironments around the time of the beginnings of ancestral hominid use of flaked stones, ca. 2.6 Ma. [Copyright &y& Elsevier]

Background: Ensete plant (Enset ventricosum) is a monocarpic perennial crop, found under genus Ensete. It is mainly known and planted by farmers as a drought resistant crop and staple food in the rural community of southern Ethiopia. Large numbers of enset clones are growing in a wide range of altitude. Currently, enset plant diversity and production has been endangered by devastated enset bacterial wilt disease (EBW) which is caused by Xanthomonas campestris pv. musacearum. The study aimed at to assess the spatial distribution of enset clone richness and diversity, and enset bacterial wilt disease in Yem special district of southern Ethiopia using ArcGIS geostatistical (Kriging) techniques.Results: The highest diversity was recorded in Semu Awash kebele with Shannon index of 3.38 and the lowest was in Nuba kebele an index of 2.56. The Sorenson similarity/variation indices showed that Gurmina Hangeri/Meleka and Ediya/Gurmina Hangeri each pairs of kebeles share 18 clones with index value of 0.81 and 0.67, respectively. While lowest share recorded between Laignaw (upper) Kesheli and Tachignaw (lower) Kesheli kebeles with Sorenson indices of 0.16 (only five clones in common recorded). Enset bacterial wilt disease is distributed in all sampled kebeles in varying ranges. The rate of disease prevalence, incidence and severity lies between ranges of 75-100%, 46.8-88.9%, and 36.1-81.4%, respectively. Semu Awasho and Laignaw Kesheli kebeles scored 100% prevalence while in Shemona Metelo kebele it is scored 75%.Conclusions: Therefore, the analyzed results indicate that it is necessary to compact EBW distribution and to conserve enset richness and diversity in the district for the sake of enhancing food security of farmers at household level in Yem special district. Otherwise, in the longer run the food security and enset plant species would be endanger and it may have significant impact on socio-economic development of the rural community. This study considered limited bio-physical factors for EBW analysis, we recommend in further research in the future should be conducted including other socio-biophysical factors. [ABSTRACT FROM AUTHOR]