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Pichi Sermolli’s work with his more than 2750 collections of plants from nearly 150 localities on the Lake Tana expedition in Ethiopia in 1937 was interrupted by World War II, but completed in 1947 at the Royal Botanic Gardens, Kew, and the British Museum (Natural History), UK. It resulted in preliminary accounts of the vegetation published 1938-40 and a taxonomically arranged account in 1951, all in Italian. Pichi Sermolli’s observations are difficult to locate due to the imperfect maps of the time, but in this book the authors have reconstructed the sequence of the collections, georeferenced the localities, and updated the identifications of the species. By reconstructing Pichi Sermolli’s observations, it is possible to draw conclusions about the vegetation and compare with a recent model of the vegetation of Ethiopia. According to this, the vegetation of the Lake Tana Basin was a complex mosaic of woodland, scrub, forest, farmland and lake shore vegetation now difficult to interpret in detail. Pichi Sermolli’s study of the vegetation in the Semien Mountains demonstrated for the first time the zonation of Ericaceous woodland and Afroalpine vegetation, within which he distinguished Carex monostachya bogs, Afroalpine grasslands with Lobelia rhynchopetalum, and stony and rocky Afroalpine vegetation. This book interprets Pichi Sermolli’s observations in English and compares them with modern knowledge of the region, partly obtained by the present authors’ own field work. It demonstrates how Pichi Sermolli’s studies form a valuable contribution to the understanding of the Ethiopian flora and vegetation.

Anacampseros specksii Dreher (Anacampserotaceae, in Flora of Ethiopia and Eritrea in Portulacaceae), was described in 2016 from plants grown from seeds collected from Bale, SE Ethiopia. The species...

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).

Question How well does the forest classification system of the 1:5,000,000 vegetation map of Africa developed by Frank White correspond with classification systems and more extensive information on species assemblages of higher resolution maps developed for Ethiopia, Kenya, Malawi, Rwanda, Tanzania, Uganda and Zambia? Methods We reviewed various national and sub-national vegetation maps for their potential in increasing the resolution of the African map. Associated documentation was consulted to compile species assemblages, and to identify indicator species, for national forest vegetation types. Indicator species were identified for each regional forest type by selecting those species that, among all the species listed for the same phytochorion (regional centre of endemism), were listed only for that forest type. For each of the national forest types, we counted the number of indicator species of the anticipated regional type. Floristic relationships (expressed by four different ecological distance measures) among national forest types were investigated based on distance-based redundancy analysis, permutational multivariate analysis of variance (PERMANOVA) using distance matrices and hierarchical clustering. Results For most of the national forests, the analysis of indicator species and floristic relationships confirmed the regional classification system for the majority of national forest types, including the allocation to different phytochoria. Permutation tests confirmed allocation of national forest types to regional typologies, although the number of possible permutations limited inferences for the Zambezian and Lake Victoria phytochoria. Two forest types from Ethiopia and Kenya did not correspond to regional forest types. Conclusions Our analysis provides support that as the classification systems are compatible, the resolution and information content of the vegetation map of Africa can be directly improved by adding information from national maps, probably leading to improved liability of its application domains. We found statistical evidence for a distinct Afromontane phytochorion. We suggest expanding the regional forest classification system with ‘Afromontane moist transitional forest’. Among the various application domains of the higher resolution maps, these maps allow for an enhanced phytochoristic analysis of eastern Africa.

Competition between neighboring plants plays a major role in the population dynamics of tree species in the early phases of humid tropical forest succession. We evaluated the relative importance of above- versus below-ground competition during the first years of old-field succession on soil with low fertility in Southern Mexico, using the premise that competition for light is size-asymmetric, unlike competition for nutrients. Plant growth is thus expected to be disproportionally impeded by larger neighbors. We studied how growth and survival of 3.5–5.5 m tall saplings of Cecropia peltata and Trichospermum mexicanum, two pioneer species that dominate the secondary forests in the study region, varied with the abundance and size of neighboring trees in 1–2 year old secondary vegetation. We found that local neighborhood basal area varied 10-fold (3 to 30 cm2 m-2) and explained most of the variation in diameter and height growth of the target saplings. Most growth variables were strongly affected by the neighbors bigger than the focal trees with no significant additive effect of the smaller neighbors, indicating asymmetric competition. Smaller neighbors did have a small but significant additive effect on the diameter growth of Cecropia saplings and stem slenderness of Trichospermum saplings. We conclude that competition for light was more important than belowground competition in this initial phase of moist tropical forest successional, despite the low soil fertility.

Livestock are the major consumers of water but also sustain millions of pastoralist and farming families. In regions where water is a scarce commodity, such as the Nile basin, there is a need for strategies to improve livestock water productivity (LWP). This study seeks to contribute to this need through a better understanding of livestock water use and productivity within the Nile basin and how this varies across the basin. We developed a spatial framework combining dynamic models of digestion in ruminants, crop water requirements (CWRs), and animal drinking water requirements to estimate spatial distribution of livestock water requirements in different livestock production systems (LPSs). We compared this with livestock production and water availability estimates within the basin. The results show that in most areas LWP is less than 0.1 USD/m3, with only few areas showing a LWP of 0.5 USD/m3 and higher. This is largely related to very low livestock meat and milk production on one hand and very variable, but, in general, low feed water productivity (fWP). Total water need for feed production was estimated to be roughly 94 billion m3, which amounts to approximately 5% of the total annual rainfall (68 billion m3 or 3.6% of total annual rainfall when excluding water for residues). Differences in LWP between systems and regions are large, suggesting considerable scope for improvements. We discuss the main factors influencing observed patterns of LWP and livestock water use and how this information can be used for developing strategies for increasing the water productivity of agricultural systems at the basin level.

As the ecology and distribution of most tree species remain poorly understood, biogeographical maps offer spatial surrogates for analysis of biodiversity patterns. We used a 1 : 250,000 potential natural vegetation map to compare the current indigenous tree species composition of 250 0.5-ha quadrats surveyed around Mount Kenya (1999– 2004) with the original species composition of ten potential natural vegetation types (PNVTs). The original 1960 vegetation map was based on intensive fieldwork and detailed aerial photographs by Trapnell et al. For each PNVT, we compiled original species lists from literature and herbarium voucher information. The percentage of species that overlap between the current list and the original list ranged from 30% to 75% for seven frequent PNVTs, but was only above 45% for dry Combretum savanna (DC). When only investigating the six to ten species with highest frequencies, these species were shared 70–100% for the four forest PNVTs, 90% for lowland Acacia-Commiphora, 67% for evergreen and semi-evergreen bushland and 50% for DC savanna. To promote agroecosystem diversification, ecological and socio-economic reasons for low current frequencies of most indigenous tree species need to be better understood.

Countries in eastern Africa have set aside significant proportions of their land for protection. But are these areas representative of the diverse range of species and habitats found in the region? And do conservation efforts include areas where the state of biodiversity is likely to deteriorate without further interventions? Various studies have addressed these questions at global and continental scales. However, meaningful conservation decisions are required at finer geographical scales. To operate more effectively at the national level, finer scale baseline data on species and on higher levels of biological organization such as the eco-regions are required, among other factors. Here we adopted a recently developed high-resolution potential natural vegetation (PNV) map for eastern Africa as a baseline to more effectively identify conservation priorities. We examined how well different potential natural vegetations (PNVs) are represented in the protected area (PA) network of eastern Africa and used a multivariate environmental similarity index to evaluate biases in PA versus PNV coverage. We additionally overlaid data of anthropogenic factors that potentially influence the natural vegetation to assess the level of threat to different PNVs. Our results indicate substantial differences in the conservation status of PNVs. In addition, particular PNVs in which biodiversity protection and ecological functions are at risk due to human influences are revealed. The data and approach presented here provide a step forward in developing more transparent and better informed translation from global priorities to regional or national implementation in eastern Africa, and are valid for other geographic regions.

The competition for water between different uses and users is increasing, particularly in the Nile basin where about 90% of the production systems comprise livestock. There is an ongoing debate on how to increase water productivity in these crop-livestock systems. This paper presents a comprehensive framework to provide policy guidance and promote action to improve returns from water investments through: (i) provision of sufficient watering points for livestock across the basin; (ii) improving water productivity through promoting water-saving technologies, ensuring system integration and control of transboundary flux of livestock diseases; and (iii) formulating participatory basin scale regulatory frameworks on water use and sharing. It also argues that improving water productivity through integrated technological, policy and institutional interventions offers an opportunity for smallholders in both upstream and downstream countries to adapt to climate and market risks.

Pastoral areas are home for more than 200 million people and provide essential environmental, economic and social services at global level. Despite the key role of grasslands for many emerging economies, these areas are historically affected by intensifying challenges, like droughts, desertification, burgeoning populations and extreme poverty. As a result of these conditions many countries in Africa, Middle East and Asia are host to a disproportionate number of the world's violent conflicts, where vulnerable pastoralist communities play a key role. The main aim of this paper is to provide an overview of the importance of pastoral areas for the security and an analysis of the role of Geomatic tools to support environmental security analysis in pastoral areas, with special consideration for the activities carried out by ILRI as part of its global mandate to eradicate poverty and insecurity through sustainable livestock production.

Both local- and landscape-scale processes drive succession of secondary forests in human-modified tropical landscapes. Nonetheless, until recently successional changes in composition and diversity have been predominantly studied at the patch level. Here, we used a unique dataset with 45 randomly selected sites across a mixed-use tropical landscape in central Panama to study forest succession simultaneously on local and landscape scales and across both life stages (seedling, sapling, juvenile and adult trees) and life forms (shrubs, trees, lianas, and palms). To understand the potential of these secondary forests to conserve tree species diversity, we also evaluated the diversity of species that can persist as viable metapopulations in a dynamic patchwork of short-lived successional forests, using different assumptions about the average relative size at reproductive maturity. We found a deterministic shift in the diversity and composition of the local plant communities as well as the metacommunity, driven by variation in the rate at which species recruited into and disappeared from the secondary forests across the landscape. Our results indicate that dispersal limitation and the successional niche operate simultaneously and shape successional dynamics of the metacommunity of these early secondary forests. A high diversity of plant species across the metacommunity of early secondary forests shows a potential for restoration of diverse forests through natural succession, when trees and fragments of older forests are maintained in the agricultural matrix and land is abandoned or set aside for a long period of time. On the other hand, during the first 32 years the number of species with mature-sized individuals was a relatively small and strongly biased sub-sample of the total species pool. This implies that ephemeral secondary forests have a limited role in the long-term conservation of tree species diversity in human-modified tropical landscapes. Both local- and landscape-scale processes drive succession of secondary forests in human-modified tropical landscapes. Nonetheless, until recently successional changes in composition and diversity have been predominantly studied at the patch level. Here, we used a unique dataset with 45 randomly selected sites across a mixed-use tropical landscape in central Panama to study forest succession simultaneously on local and landscape scales and across both life stages (seedling, sapling, juvenile and adult trees) and life forms (shrubs, trees, lianas, and palms). To understand the potential of these secondary forests to conserve tree species diversity, we also evaluated the diversity of species that can persist as viable metapopulations in a dynamic patchwork of short-lived successional forests, using different assumptions about the average relative size at reproductive maturity. We found a deterministic shift in the diversity and composition of the local plant communities as well as the metacommunity, driven by variation in the rate at which species recruited into and disappeared from the secondary forests across the landscape. Our results indicate that dispersal limitation and the successional niche operate simultaneously and shape successional dynamics of the metacommunity of these early secondary forests. A high diversity of plant species across the metacommunity of early secondary forests shows a potential for restoration of diverse forests through natural succession, when trees and fragments of older forests are maintained in the agricultural matrix and land is abandoned or set aside for a long period of time. On the other hand, during the first 32 years the number of species with mature-sized individuals was a relatively small and strongly biased sub-sample of the total species pool. This implies that ephemeral secondary forests have a limited role in the long-term conservation of tree species diversity in human-modified tropical landscapes.