Paulo van Breugel

An ecoregion-based approach to protecting half the terrestrial realm

Abstract 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 Earths 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.

Succession of Ephemeral Secondary Forests and Their Limited Role for the Conservation of Floristic Diversity in a Human-Modified Tropical Landscape

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.

Environmental Gap Analysis to Prioritize Conservation Efforts in Eastern Africa

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.

A meta-analysis of molecular marker genetic datasets for eastern Africa trees supports the utility of potential natural vegetation maps for planning climate-smart restoration initiatives

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.

The Gerire Hills, a SE Ethiopian outpost of the transitional semi-evergreen bushland: vegetation, endemism and three new species, Croton elkerensis (Euphorbiaceae), Gnidia elkerensis (Thymelaeaceae), and Plectranthus spananthus (Lamiaceae)

ABSTRACT 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, about 160 km from continuously distributed vegetation of this type. In the lowland surrounding the hills is deciduous Acacia-Commiphora bushland, typical of the Somalia-Masai region. Unpublished data from a 1937 Italian expedition documents past existence of Juniperus procera on the plateaux. Three new narrowly endemic species are described here from recently collected material: Croton elkerensis Friis & M.G. Gilbert (Euphorbiaceae), Gnidia elkerensis Friis & Sebsebe (Thymelaeaceae), and Plectranthus spananthus A.J. Paton, Friis & Sebsebe (Lamiaceae). Three previously described species from the hills, Blepharispermum obovatum Chiov. (Asteraceae), Aloe elkerriana Dioli & T.A.McCoy (Aloaceae) and Euphorbia bertemariae Bisseret & Dioli (Euphorbiaceae), are narrow endemics. The species most similar to the bushland endemics occur in a range of vegetation types and phytochoria in East Africa south of Ethiopia or more widespread in Africa. The species most similar to the succulent endemics occur elsewhere in semi-evergreen bushland on limestone at the mountain range in northern Somalia. The Gerire Hills endemics are considered Vulnerable (VU) or Least Concern (LC) given the differing threats to their respective habitats.

Kalanchoe hypseloleuce (Crassulaceae), a new species from eastern Ethiopia, with notes on its habitat

SummaryA 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).