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Fire‐adapted species invading fire‐prone ecosystems in Mediterranean climate regions are difficult to control because they are equally responsive to restoration treatments. We assessed the efficacy of delaying a prescribed burn to promote the recruitment of native species in a Lowland Sand Fynbos ecosystem invaded by alien Acacia saligna. Acacia stands were felled and fallowed for 2 years before burning the slash and sowing pre‐treated fynbos seeds. We hypothesized that sowing pre‐treated fynbos seeds after fallowing cleared areas before burning would improve the regeneration of native species. Fallowing cleared areas would reduce the density of acacia seeds and post‐fire acacia recruitment while allowing felled acacia biomass to dry and decay over time leading to improved prescribed burn properties. Sowing pre‐treated fynbos seeds improved the recovery of native cover but had little effect on the recovery of native species diversity after 2 years. Although the rapid recruitment of annual native species did not affect acacia density, it might have contributed to reduced post‐fire acacia cover and allowed the native perennial species to establish. After 2 years of fallowing cleared areas, the density of acacia seeds and post‐fire acacia recruitment was reduced by ≈50% and 80% respectively. Although too dense to be outcompeted by recruited native species alone, this reduced acacia recruitment helped to decrease and delay the need for follow‐up acacia clearing as it was where burning occurred soon after felling acacia stands. The recruited native species managed to establish before the acacia emergents were removed unlike where burning occurs soon after felling and where native species were outcompeted resulting in the need for follow‐up sowing. In conclusion, building resilience against acacia resurgence by increasing the pool of sown species to recover a good cover of native species in combination with the timely removal of acacia recruits can help to scale up restoration. [ABSTRACT FROM AUTHOR]

Summary: Understanding and predicting recruitment in species‐rich plant communities requires identifying functional determinants of both density‐independent performance and interactions.In a common‐garden field experiment with 25 species of the woody plant genus Protea, we varied the initial spatial and taxonomic arrangement of seedlings and followed their survival and growth during recruitment. Neighbourhood models quantified how six key functional traits affect density‐independent performance, interaction effects and responses.Trait‐based neighbourhood models accurately predicted individual survival and growth from the initial spatial and functional composition of species‐rich experimental communities. Functional variation among species caused substantial variation in density‐independent survival and growth that was not correlated with interaction effects and responses. Interactions were spatially restricted but had important, predominantly competitive, effects on recruitment. Traits increasing the acquisition of limiting resources (water for survival and soil P for growth) mediated trade‐offs between interaction effects and responses. Moreover, resprouting species had higher survival but reduced growth, likely reinforcing the survival–growth trade‐off in adult plants.Resource acquisition of juvenile plants shapes Protea community dynamics with acquisitive species with strong competitive effects suffering more from competition. Together with functional determinants of density‐independent performance, this makes recruitment remarkably predictable, which is critical for efficient restoration and near‐term ecological forecasts of species‐rich communities. [ABSTRACT FROM AUTHOR]

Unprecedented urbanisation in the Global South is transforming natural urban landscapes, impacting on the ability of nature to provide essential ecosystem services.Within the context of pressures facing many urban natural open spaces, particularly in Africa, we used a local municipality in South Africa as a case study to (i) identify local government priorities for a natural open space system; (ii) develop an understanding of whether, and how, ecosystem services are considered by local government, and the reasons thereof; and (iii) ascertain the extent of proactive planning regarding regulating and other ecosystem services, including the temporal and spatial scales, and implications. In‐depth qualitative interviews (n = 12) were undertaken with senior municipal officials representing departments whose work impacts the environment. Municipal decision‐support documents were also analysed for any direct and/or indirect references to ecosystem services.Planning for, and management of, ecosystem services provided by natural open spaces is influenced by interwoven infrastructure, municipal service delivery and equity challenges, complex institutional constraints and poverty, with little focus on the socio‐economic opportunities and other benefits of natural open space systems. Values, perceptions and knowledge also influence the management of ecosystem services.The study contributes to understanding the opportunities and challenges for the future governance of natural open space in the Global South, which require explicit consideration in municipal planning, management and budgeting processes.Policy and management implications identified include prioritisation of the regulating functions provided by natural open space systems, pivotal to the urban resilience agenda; building on the inherent appreciation of nature features as city assets, while achieving socio‐economic upliftment; improved (on‐site) collaborative management of natural open spaces; and involvement of local government officials in the preparation and updating of environmental policies and decision‐support documents, to ensure skills and knowledge transfer and interest are entrenched in local government departments. Read the free Plain Language Summary for this article on the Journal blog. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Sustainability-focused research networks and communities of practice have emerged as a key response and strategy to build capacity and knowledge to support transformation towards more sustainable, just and equitable futures. This paper synthesises insights from the development of a community of practice on social-ecological systems (SES) research in southern Africa over the past decade, linked to the international Programme on Ecosystem Change and Society (PECS). This community consists of a network of researchers who carry out place-based SES research in the southern African region. They interact through various cross-cutting working groups and also host a variety of public colloquia and student and practitioner training events. Known as the Southern African Program on Ecosystem Change and Society (SAPECS), its core objectives are to: (1) derive new approaches and empirical insights on SES dynamics in the southern African context; (2) have a tangible impact by mainstreaming knowledge into policy and practice; and (3) grow the community of practice engaged in SES research and governance, including researchers, students and practitioners. This paper reflects on experiences in building the SAPECS community, with the aim of supporting the development of similar networks elsewhere in the world, particularly in the Global South. [ABSTRACT FROM AUTHOR]

Invasive alien species (IAS) are one of the most important factors driving extinction rates worldwide. Among the IAS, the impacts of introduced mammals on native biodiversity are most severe, with the European rabbit (Oryctolagus cuniculus) being the most problematic. Globally, European rabbits have been introduced to five continents and more than 800 islands or island groups where they are a threat to biodiversity and human livelihoods. The impacts of European rabbits on biodiversity and human livelihoods have been extensively studied across the globe. However, some regions of the world, such as the offshore islands along Africa's southern coast, have been sparsely studied. In this study, we monitored change in grazing capacity on a South African offshore island, Robben Island, following an attempt to eradicate European rabbits between 2008 and 2009. Grazing capacity on the island increased following rabbit control, driven by the recovery of palatable plant species in response to release from herbivory. There was no change in grazing capacity at sites under Eucalyptus plantations because of the inhibitory effects of the alien trees on understory vegetation dynamics. We believe that grazing capacity changes on Robben Island are indicative of potential vegetation changes on other southern African offshore islands. [ABSTRACT FROM AUTHOR]

Combined studies of the communities and interaction networks of bird and insect pollinators are rare, especially along environmental gradients. Here, we determined how disturbance by fire and variation in sugar resources shape pollinator communities and interactions between plants and their pollinating insects and birds. We recorded insect and bird visits to 21 Protea species across 21 study sites and for 2 years in Fynbos ecosystems in the Western Cape, South Africa. We recorded morphological traits of all pollinator species (41 insect and nine bird species). For each site, we obtained estimates of the time since the last fire (range: 2–25 calendar years) and the Protea nectar sugar amount per hectare (range: 74–62 000 g/ha). We tested how post‐fire age and sugar amount influence the total interaction frequency, species richness and functional diversity of pollinator communities, as well as pollinator specialization (the effective number of plant partners) and potential pollination services (pollination service index) of insects and birds. We found little variation in the total interaction frequency, species richness and functional diversity of insect and bird pollinator communities, but insect species richness increased with post‐fire age. Pollinator specialization and potential pollination services of insects and birds varied differently along the environmental gradients. Bird pollinators visited fewer Protea species at sites with high sugar amount, while there was no such trend for insects. Potential pollination services of insect pollinators to Protea species decreased with increasing post‐fire age and resource amounts, whereas potential pollination services of birds remained constant along the environmental gradients. Despite little changes in pollinator communities, our analyses reveal that insect and bird pollinators differ in their specialization on Protea species and show distinct responses to disturbance and resource gradients. Our comparative study of bird and insect pollinators demonstrates that birds may be able to provide more stable pollination services than insects. [ABSTRACT FROM AUTHOR]

Invasive alien plants (IAPs) pose a serious threat to biodiversity, agriculture, health, and economies globally. Accurate mapping of IAPs is crucial for their management, to mitigate their impacts and prevent further spread where possible. Remote sensing has become a valuable tool in detecting IAPs, especially with freely available data such as Sentinel-2 satellite imagery. Yet, remote sensing methods to map herbaceous IAPs, which tend to be more difficult to detect, particularly in shrubland Mediterranean-type ecosystems, are still limited. There is a growing need to detect herbaceous IAPs at a large scale for monitoring and management; however, for countries or organizations with limited budgets, this is often not feasible. To address this, we aimed to develop a classification methodology based on optical satellite data to map herbaceous IAP's using Echium plantagineum as a case study in the Fynbos Biome of South Africa. We investigate the use of freely available Sentinel-2 data, use the robust non-parametric classifier Random Forest, and identify the most important variables in the classification, all within the cloud-based platform, Google Earth Engine. Findings reveal the importance of the shortwave infrared and red-edge parts of the spectrum and the importance of including vegetation indices in the classification for discriminating E. plantagineum. Here, we demonstrate the potential of Sentinel-2 data, the Random Forest classifier, and Google Earth Engine for mapping herbaceous IAPs in Mediterranean ecosystems. [ABSTRACT FROM AUTHOR]