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Indonesia's tropical peatlands are crucial global carbon stores but have been heavily degraded in recent decades. We present seven principles for equitable and resilient tropical peatland restoration in Central Kalimantan, Indonesia, host to 19% of Indonesia's tropical peatland area, where local livelihoods, cultural practices, and indigenous social relations remain closely connected. Our collaborative methods employed a Delphi survey and focus group discussions with researchers from various disciplines to develop a shared vision for restoration. This vision served as a boundary object during interviews with diverse stakeholders involved in peatland restoration in Central Kalimantan, allowing for refinement and adaptation of the vision and the development of principles to achieve it. The principles emphasize inclusive and collaborative decision‐making, planning, and implementation; site‐specific approaches adapted to local social and ecological conditions; and ensuring the informed consent of and fair benefit distribution to all local social groups. They also emphasize a holistic, integrated, and long‐term approach to restoration that considers multiple aspects, including hydrological function, vegetation regeneration, fire prevention, locally appropriate livelihood benefits, inclusive governance, and adaptive management practices. These principles serve as a starting point for resilience‐oriented social‐ecological restoration practice and policy formulation, aiming to facilitate equitable, effective, and resilient tropical peatland restoration outcomes. [ABSTRACT FROM AUTHOR]

Climate warming has been linked to shrub expansion in alpine regions and the decomposition of shrub leaf litter and subsequent release of nutrients has been proposed as a mechanism to facilitate shrub growth. We quantified the rate of alpine shrub leaf litter decomposition (measured as mass loss) over the course of a year in four locally occurring alpine shrub species that grow across four alpine summits. We measured a range of environmental attributes at the study sites, and via a standard litter bag approach, we evaluated the effects of site elevation, the depth of litter bag deployment, the removal time, the species‐specific leaf area (SLA) and the accumulated growing degree days at each site on the total per cent and rate of litter decomposition (as mass loss). The higher elevation sites were cooler with more snow days than the lower sites. Soil moisture was higher early in the snow‐free season at the higher elevation sites. Linear mixed effect models indicated no significant effects of elevation on total and rate of litter decomposition, but there were significant positive effects of deployment depth and removal time and a significant negative effect of species SLA. There were significant negative relationships between the rate of decomposition and growing degree days, as decomposition slows through time. The modelled mean rates of shrub litter decomposition for each species indicated that there would be more and faster decomposition if winter and early spring conditions were to persist for a whole year, compared with the modelled rates of average annual conditions persisting for a whole year. Our results indicate that Australian alpine shrub litter decomposes readily, with the highest rates of decomposition occurring soon after deployment, which in this study was after a snowy winter at the start of the growing season in spring. [ABSTRACT FROM AUTHOR]

Peatlands are found on all continents, covering 3% of the global land area. However, the spatial extent and causes of metal enrichment in peatlands is understudied and no attempt has been made to evaluate global patterns of metal enrichment in bog and fen peatlands, despite that certain metals and rare earth elements (REE) arise from anthropogenic sources. We analyzed 368 peat cores sampled in 16 countries across five continents and measured metal and other element concentrations at three depths down to 70 cm as well as estimated cumulative atmospheric S deposition (1850–2009) for each site. Sites were assigned to one of three distinct broadly recognized peatland categories (bog, poor fen, and intermediate-to-moderately rich fen) that varied primarily along a pH gradient. Metal concentrations differed among peatland types, with intermediate-to-moderately rich fens demonstrating the highest concentrations of most metals. Median enrichment factors (EFs; a metric comparing natural and anthropogenic metal deposition) for individual metals were similar among bogs and fens (all groups), with metals likely to be influenced by anthropogenic sources (As, Cd, Co, Cu, Hg, Pb, and Sb) demonstrating median enrichment factors (EFs) > 1.5. Additionally, mean EFs were substantially higher than median values, and the positive correlation (< 0.40) with estimated cumulative atmospheric S deposition, confirmed some level of anthropogenic influence of all pollutant metals except for Hg that was unrelated to S deposition. Contrary to expectations, high EFs were not restricted to pollutant metals, with Mn, K and Rb all exhibiting elevated median EFs that were in the same range as pollutant metals likely due to peatland biogeochemical processes leading to enrichment of these nutrients in surface soil horizons. The global patterns of metal enrichment in bogs and fens identified in this study underscore the importance of these peatlands as environmental archives of metal deposition, but also illustrates that biogeochemical processes can enrich metals in surface peat and EFs alone do not necessarily indicate atmospheric contamination. [ABSTRACT FROM AUTHOR]

Savanna ecosystems comprise 22% of the global terrestrial surface and 25% of Australia (almost 1.9 million km2) and provide significant ecosystem services through carbon and water cycles and the maintenance of biodiversity. The current structure, composition and distribution of Australian savannas have coevolved with fire, yet remain driven by the dynamic constraints of their bioclimatic niche. Fire in Australian savannas influences both the biophysical and biogeochemical processes at multiple scales from leaf to landscape. Here, we present the latest emission estimates from Australian savanna biomass burning and their contribution to global greenhouse gas budgets. We then review our understanding of the impacts of fire on ecosystem function and local surface water and heat balances, which in turn influence regional climate. We show how savanna fires are coupled to the global climate through the carbon cycle and fire regimes. We present new research that climate change is likely to alter the structure and function of savannas through shifts in moisture availability and increases in atmospheric carbon dioxide, in turn altering fire regimes with further feedbacks to climate. We explore opportunities to reduce net greenhouse gas emissions from savanna ecosystems through changes in savanna fire management. [ABSTRACT FROM AUTHOR]

Bog peat soils have been accumulating at Wellington Plain peatland, Victoria, Australia for the last 3300 years. Now, dried peat soils are common adjacent to bog peats. The 14C basal age of dried peat is not different from the 14C basal age of bog peat, which supports the theory that dried peat formed from bog peat. A novel application of 210Pb dating links the timing of this change with the introduction of livestock to Wellington Plain in the mid-1800s. Physical loss of material appears to have been the dominant process removing material as bog peats drained to form dried peats, as indicated by the mass balances of carbon and lead. This research has implications for the post-fire and post-grazing restoration of bogs in Victoria's Alpine National Park, and the contribution of peat soils to Australia's carbon emissions. [ABSTRACT FROM AUTHOR]