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The vegetation of the plateaux of the Gerire Hills, of unique geology, represents an outlier of the Transitional semi-evergreen bushland of the eastern escarpment of the Ethiopian highlands...

We assess progress toward the protection of 50% of the terrestrial biosphere to address the species-extinction crisis and conserve a global ecological heritage for future generations. Using a map of Earth's 846 terrestrial ecoregions, we show that 98 ecoregions (12%) exceed Half Protected; 313 ecoregions (37%) fall short of Half Protected but have sufficient unaltered habitat remaining to reach the target; and 207 ecoregions (24%) are in peril, where an average of only 4% of natural habitat remains. We propose a Global Deal for Nature—a companion to the Paris Climate Deal—to promote increased habitat protection and restoration, national- and ecoregion-scale conservation strategies, and the empowerment of indigenous peoples to protect their sovereign lands. The goal of such an accord would be to protect half the terrestrial realm by 2050 to halt the extinction crisis while sustaining human livelihoods.

The impact of climate change on ecosystems, especially at the species level, is already being observed across the world. To assess potential future climate change effects on species, scientists often use species distribution modelling (SDM). The estimation of likely changes in the distribution of species under future climate conditions is a crucial first step towards the mitigation and management of future species losses or habitat shifts. Considering this, the aim of the present study is to predict the effect of climate change on a valuable threatened tree species, Mangifera sylvatica Roxb., of Bangladesh using Maximum Entropy. The current potential distribution as by the model suggests that around 5% of the study area is highly suitable wild mango habitat, with between 6% and 11% being moderately suitable. Under the RCP 4.5 scenario, the net decrease in suitable habitat is predicted to be 7% by 2070. Under the RCP 8.5 scenario, the model predicts that the total area suitable for mango will reduce by 12% by 2050, disappearing altogether by 2070. Therefore, urgent measures are required for the conservation of M. sylvatica in Bangladesh. The application of the species distribution model may provide policymakers and conservationists with a useful tool for the prediction of future distribution (at both local and regional scales); of poorly known species with high preservation concerns. The approach used in this study can provide a rapid assessment of the future conservation status of other important forest tree species in Bangladesh to improve our understanding of the vulnerability under changing climate.

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.

Forest and woodland landscape restoration is a key undertaking of renewed interest for forestry and conservation practitioners, but is hampered by the lack of information on the distributions of tree species and of patterns of intra-specific genetic variation. Through the first meta-analysis of its type, we here tested the utility of a high-resolution potential natural vegetation (PNV) map for eastern Africa (vegetationmap4africa) for supporting restoration activities by comparison with 20 molecular marker genetic datasets, identified through literature review and other sources, for ten indigenous tree species. Our analysis indicated that site suitability and stability values from PNV-based ecological niche modelling involving current and past climate scenarios were positively related to population genetic diversity values revealed by molecular markers, supporting the value of PNV maps for the practical planning of restoration activities accounting for anthropogenic climate change. Furthermore, population pairwise genetic divergence was strongly positively correlated with population pairwise geographic distances for most datasets, indicating generalizable sampling implications for tree genetic resource conservation in the region. Population pairwise genetic divergence was however not well explained by sampling across PNV and wider physiognomic types, possibly due to molecular markers’ adaptive neutrality and high rates of recombination in trees, among other factors. Patterns of neutral molecular marker variation are thus no substitute for trials of adaptive variation for confirming or refuting the utility of vegetation boundaries in defining tree planting zones. We discuss the importance of results for eastern Africa and more widely.

A new species of Kalanchoe, K. hypseloleuce Friis & M. G. Gilbert, was found during field work in Ethiopia in 2015, and is established here. It is characterised by its tall stature (2 – 3 m), entire, sessile, lanceolate leaves and pure white flowers with abaxially minutely papillose corolla lobes (otherwise, the plant is glabrous). It is not obviously related to any previously known species, but an earlier, incomplete specimen has been cited as K. prittwitzii Engl. in the literature. K. hypseloleuce was collected on limestone in Acacia-Commiphora woodland and bushland at c. 1400 m a.s.l. It occurs in the southern part of the eastern Ethiopian escarpment in the Arsi and Eastern Harerghe zones of the Oromo Regional State. K. hypseloleuce is documented with images and maps, its climate envelope has been modelled, and a conservation assessment made. With the current level of threat, this could be Vulnerable to Near Threatened (VU-NT). Given the threat from habitat degradation is not imminent, we recommend the species to be listed as Near Threatened (NT).