Positive biodiversity-ecosystem function relationships (BEFRs) have been widely documented, but it is unclear if BEFRs should be expected in disturbance-driven systems. Disturbance may limit competition and niche differentiation, which are frequently posited to underlie BEFRs. We provide the first exploration of the relationship between tree species diversity and biomass, one measure of ecosystem function, across southern African woodlands and savannas, an ecological system rife with disturbance from fire, herbivores and humans.We used > 1000 vegetation plots distributed across 10 southern African countries and structural equation modelling to determine the relationship between tree species diversity and above-ground woody biomass, accounting for interacting effects of resource availability, disturbance by fire, tree stem density and vegetation type.We found positive effects of tree species diversity on above-ground biomass, operating via increased structural diversity. The observed BEFR was highly dependent on organismal density, with a minimum threshold of c. 180 mature stems ha −1 . We found that water availability mainly affects biomass indirectly, via increasing species diversity.The study underlines the close association between tree diversity, ecosystem structure, environment and function in highly disturbed savannas and woodlands. We suggest that tree diversity is an under-appreciated determinant of wooded ecosystem structure and function.

National education policies are increasingly regulated by international agendas, for example the Agenda 2030 for Sustainable Development (SD). However, in order to put such policies into practice, social actors like teachers and teacher educators must include them in their practices. In this context, this study stems from the following research question: how does initial teacher education (ITE) promote the SD Agendas (2030 and 2063 for Africa)? The approach to this question is carried out through a case study focused on an Angolan teacher education higher education institution, in its graduate course for future secondary school biology teachers. The main aims of this study are (i) to characterize how ITE includes SD and (ii) to suggest ways to improve SD, particularly focusing on students’ future professional needs. Data were gathered from document analysis (the pedagogical curriculum plan of the course; titles and abstracts of final-year future biology teachers’ essays) and an interview with the course director of the biology teaching program of the Angolan institution. Content analysis of the gathered evidence was based on a three-dimensional framework: (a) SD goals (SDG) and the curriculum; (b) teacher education principles; and (c) current Angolan curricular perspectives. Results show that although the Pedagogical curriculum plan and the formative path, from the interviewee’s point of view, do not explicitly integrate SDG and its challenges for biology ITE, the majority of essays analyzed are locally contextualized and in a number of cases articulated with some of the 17 SDG. Suggestions for inclusion of SDG in ITE and for teacher education research are put forward.

Seasonally dry woodlands are the dominant land cover across southern Africa. They are biodiverse, structurally complex, and important for ecosystem service provision. Species composition and structure vary across the region producing a diverse array of woodland types. The woodlands of the Huíla plateau in southwest Angola represent the extreme southwestern extent of the miombo ecoregion and are markedly drier than other woodlands within this ecoregion. They remain understudied, however, compared to woodlands further east in the miombo ecoregion. We aimed to elucidate further the tree diversity found within southwestern Angolan woodlands by conducting a plot-based study in Bicuar National Park, comparing tree species composition and woodland structure with similar plots in Tanzania, Mozambique, and the Democratic Republic of Congo. We found Bicuar National Park had comparatively low tree species diversity, but contained 27 tree species not found in other plots. Plots in Bicuar had low basal area, excepting plots dominated by Baikiaea plurijuga. In a comparison of plots in intact vegetation with areas previously disturbed by shifting-cultivation agriculture, we found species diversity was marginally higher in disturbed plots. Bicuar National Park remains an important woodland refuge in Angola, with an uncommon mosaic of woodland types within a small area. While we highlight wide variation in species composition and woodland structure across the miombo ecoregion, plot-based studies with more dense sampling across the ecoregion are clearly needed to more broadly understand regional variation in vegetation diversity, composition and structure.

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