Southeast Asia (SEA) contributes approximately one-third of global land-use change carbon emissions, a substantial yet highly uncertain part of which is from anthropogenically-modified peat swamp forests (PSFs) and mangroves. Here, we report that between 2001–2022 land-use change impacting PSFs and mangroves in SEA generate approximately 691.8±97.2 teragrams of CO₂ equivalent emissions annually (TgCO₂eyr⁻¹) or 48% of region’s land-use change emissions, and carbon removal through secondary regrowth of −16.3 ± 2.0 TgCO₂eyr⁻¹. Indonesia (73%), Malaysia (14%), Myanmar (7%), and Vietnam (2%) combined accounted for over 90% of regional emissions from these sources. Consequently, great potential exists for emissions reduction through PSFs and mangroves conservation. Moreover, restoring degraded PSFs and mangroves could provide an additional annual mitigation potential of 94.4 ± 7.4 TgCO₂eyr⁻¹. Although peatlands and mangroves occupy only 5.4% of SEA land area, restoring and protecting these carbon-dense ecosystems can contribute substantially to climate change mitigation, while maintaining valuable ecosystem services, livelihoods and biodiversity.

Indonesia is the largest archipelagic country in the world, with 17,000 islands of varying sizes and elevations, from lowlands to very high mountains, stretching more than 5000 km eastward from Sabang in Aceh to Merauke in Papua. Although occupying only 1.3% of the world’s land area, Indonesia possesses the third-largest rainforest and the second-highest level of biodiversity, with very high species diversity and endemism. However, during the last two decades, Indonesia has been known as a country with a high level of deforestation, a producer of smoke from burning forests and land, and a producer of carbon emissions. The aim of this paper is to review the environmental history and the long process of Indonesian forest management towards achieving environmental sustainability and community welfare. To do this, we analyze the milestones of Indonesian forest management history, present and future challenges, and provide strategic recommendations toward a viable Sustainable Forest Management (SFM) system. Our review showed that the history of forestry management in Indonesia has evolved through a long process, especially related to contestation over the control of natural resources and supporting policies and regulations. During the process, many efforts have been applied to reduce the deforestation rate, such as a moratorium on permitting primary natural forest and peat land, land rehabilitation and soil conservation, environmental protection, and other significant regulations. Therefore, these efforts should be maintained and improved continuously in the future due to their significant positive impacts on a variety of forest areas toward the achievement of viable SFM. Finally, we conclude that the Indonesian government has struggled to formulate sustainable forest management policies that balance economic, ecological, and social needs, among others, through developing and implementing social forestry instruments, developing and implementing human resource capacity, increasing community literacy, strengthening forest governance by eliminating ambiguity and overlapping regulations, simplification of bureaucracy, revitalization of traditional wisdom, and fair law enforcement.

Reforestation in the tropics is highlighted as an important intervention to mitigate climate change globally because of its potential for high CO₂ removal rates, ranging from 4.5 to 40.7 t CO₂e ha⁻¹ yr⁻¹ during the first 20 years of tree growth. Reforestation is critical to meeting emissions’ targets of the Paris Climate Agreement, as well as achieving Indonesia’s Nationally Determined Contribution (NDC) targets. Increasing carbon stocks through forest and land rehabilitation activities (RHL) is one of the Ministry of Environment and Forestry (MoEF) five main strategies for reducing greenhouse gas (GHG) emissions from the land sector. This study focuses on reforestation opportunities to support Indonesia’s NDC in reducing GHG emissions by 2030. We identified unproductive areas of land (shrub, open land) with highly degraded conditions as potential areas for reforestation. Based on Indonesian data of land cover change, we found that reforestation activities during 2019–2030 (11 years) under a realistic, ambitious and very ambitious scenario may remove carbon up to −0.25 GtCO₂e (equal to −23 MtCO₂e yr⁻¹), −1.3 GtCO₂e (equal to −124 MtCO₂e yr⁻¹) and −2.7 GtCO₂e (equal to −247 MtCO₂e yr⁻¹), respectively. Based on international data of land cover change (Hansen et al. 2013), reforestation activities during 2019–2030, under a realistic, ambitious, and very ambitious scenario, have the opportunities to remove −17 MtCO₂e yr⁻¹, −118 MtCO₂e yr⁻¹, and −241 MtCO₂e yr⁻¹, respectively. This study demonstrates that ambitious and very ambitious scenarios of reforestation activities can significantly contribute to Indonesia’s forestry-related NDC in 2030 by reducing the Indonesia Business As Usual (BAU) emissions up to 17% and 35%.

Tropical peatlands are areas of high carbon density that are important in biosphere-atmosphere interactions. Drainage and burning of tropical peatlands releases about 5% of global greenhouse gas (GHG) emissions, yet there is great uncertainty in these estimates. Our comprehensive literature review of parameters required to calculate GHG emissions from burnt peat forests, following the international guidelines, revealed many gaps in knowledge of carbon pools and few recent supporting studies. To improve future estimates of the total ecosystem carbon balance and peatfire emissions this study aimed to account for all carbon pools: aboveground, deadwood, pyrogenic carbon (PyC) and peat of single and repeatedly burnt peat forests. A further aim was to identify the minimum sampling intensity required to detect with 80% power significant differences in these carbon pools among long unburnt, recently burnt and repeatedly burnt peat swamp forests. About 90 Mg C ha^-1 remains aboveground as deadwood after a single fire and half of this remains after a second fire. One fire produces 4.5 ± 0.6 Mg C ha^-1 of PyC, with a second fire increasing this to 7.1 ± 0.8 Mg C ha^-1. For peat swamp forests these aboveground carbon pools are rarely accounted in estimates of emissions following multiple fires, while PyC has not been included in the total peat carbon mass balance. Peat bulk density and peat carbon content change with fire frequency, yet these parameters often remain constant in the published emission estimates following a single and multiple fires. Our power analysis indicated that as few as 12 plots are required to detect meaningful differences between fire treatments for the major carbon pools. Further field studies directed at improving the parameters for calculating carbon balance of disturbed peat forest ecosystems are required to better constrain peatfire GHG emission estimates.

A strategy that has the potential to contribute to the achievement of the targets established under SDG 8 (“Decent Work and Economic Growth”) involves the development of sustainable tourism to create productive job and livelihood opportunities and to promote local culture and products. In the province of East Nusa Tenggara (NTT), Indonesia, ikat weaving is an integral part of the cultural heritage of the region, with ikat characterized by unique design motives and the use of natural dyes. Unfortunately, in some areas, the use of natural dyes is diminishing as a result of competition with synthetic dyes and the limited availability of raw materials, particularly for the production of blue dye. The development of Indigofera spp. to produce natural, plant-based blue dye has significant potential to contribute to community incomes and employment. This study outlines a strategy for developing the use of Indigofera spp. as a natural dye and describes its potential for contributing to community incomes, especially on Timor Island, NTT. The study shows that weavers currently use indigo plants that grow naturally in gardens and yards. Although the community has a tradition of using these plants, informed by local wisdom, to develop the cultivation and processing of this plant through the application of the appropriate techniques, including innovative approaches to producing indigo paste, could enable the development of Indigofera spp. cultivation on a larger scale. The study shows that the availability of suitable land is high (±370 thousand ha), with 80% of the suitable land being categorized as critical. The study proposes a development based on the analysis of strengths, weaknesses, opportunities, and threats to assess the manner in which these opportunities could be leveraged with the support and participation of local communities and other stakeholders by leveraging the culture and wisdom of the community regarding the use of Indigofera spp.