• Energy Research

Abstract Ecosystem restoration is increasingly employed as a nature-based solution to a range of crises. Decisions over restoration must balance limited resources, land constraints, and competing demands. Peatlands in Southeast Asia have been heavily impacted by agricultural expansion over the past three decades, with Indonesia now accounting for a substantial proportion of degraded tropical peatlands globally. Using spatial linear programming, we focus on prioritizing peatland restoration sites in Indonesia for fire risk reduction, climate change mitigation, species conservation, and cost-effectiveness. The study finds that restoring peatlands at 1 km2 planning units can generate multiple co-benefits such as reduced fire risks by 6%–37%, attenuated extinction risks of peatland specialist bird species and mitigated climate change potential of 0.002–0.36 Pg CO2e yr−1. These benefits were reduced but still of comparable magnitude when larger areas of planning (defined by village and catchment boundaries) were used. The results, although indicative, support tropical peatland restoration as a cost-efficient strategy for mitigating climate change, reducing fire, conserving biodiversity, and supporting sustainable development that can be offset by carbon prices of USD 2–37/Mg CO2e.

COVID-19 has changed the permeability of borders in transboundary environmental governance regimes. While borders have always been selectively permeable, the pandemic has reconfigured the nature of cross-border flows of people, natural resources, finances and technologies. This has altered the availability of spaces for enacting sustainability initiatives within and between countries. In Southeast Asia, national governments and businesses seeking to expedite economic recovery from the pandemic-induced recession have selectively re-opened borders by accelerating production and revitalizing agro-export growth. Widening regional inequities have also contributed to increased cross-border flows of illicit commodities, such as trafficked wildlife. At the same time, border restrictions under the exigencies of controlling the pandemic have led to a rolling back and scaling down of transboundary environmental agreements, regulations and programs, with important implications for environmental democracy, socio-ecological justice and sustainability. Drawing on evidence from Southeast Asia, the article assesses the policy challenges and opportunities posed by the shifting permeability of borders for organising and operationalising environmental activities at different scales of transboundary governance.

10.25540/g460-wgdf

AbstractAimDetermine the extent to which remote, high‐altitude (Afroalpine) aquatic ecosystems in tropical Africa have been impacted by global and regional‐scale environmental change processes.LocationTwo volcanic crater lakes (Bisoke and Muhavura) in the Afroalpine zone, Albertine (Western) Rift, central Africa.MethodsSediment cores were collected from Bisoke and Muhavura lakes and dated using radiometric techniques. A range of sediment‐based proxies was extracted from the cores and quantified. Sedimentary data were subjected to statistical analyses that contributed to the identification of influential environmental variables and their effects on diatom assemblages, the determination of variations in spatial beta diversity and estimates of the rate of compositional turnover over the last c. 1,200 years.ResultsSediments from the two sites provide evidence of the sensitivity of remote, Afroalpine aquatic ecosystems to perturbation. Climate variability has been a major driver of ecological change, particularly at Bisoke Lake, throughout the c. 1,200‐year‐long record, while Muhavura Lake has been directly impacted by and recovered from at least one volcanic eruption during this time. The effects of climatic warming from the mid‐ to late 19th century and especially from the late 20th century, possibly accentuated by atmospheric deposition‐driven nutrient enrichment, appear increasingly in lockstep. Effects include changes in diatom community composition, increased productivity and compositional turnover, and biotic homogenization (reduced spatial beta diversity) between the two sites.Main conclusionsThe two Afroalpine sites record changes in atmospheric conditions and their effects on diatom assemblage composition, particularly over the last c. 150 years. Drivers of these changes have the potential to disrupt ecosystems at lower altitudes in the Albertine Rift, including biodiverse areas of forest, and across tropical Africa more widely.