•Mangrove conversion to shrimp ponds generates substantial carbon loss.•The carbon loss from mangrove conversion was mainly due to depletion of soil carbon stocks.•Shrimp production in converted ...mangroves resulted in high land use carbon footprint.
Mangroves provide a number of important ecosystem services to humanity but their persistence is threatened from deforestation, conversion, and climate change. The Mahakam Delta was once among the largest mangrove forests in Southeast Asia comprising 2% of Indonesia’s total mangroves. Currently, about 62% of this extensive mangrove in the Mahakam Delta has been lost mainly due to conversion into aquaculture. To understand the impacts of mangrove conversion on carbon losses and therefore their values in climate change mitigation, we sampled 10 intact mangroves and 10 abandoned shrimp ponds to quantify: (1) the total ecosystem carbon stocks; (2) potential CO2 emissions arising from mangrove conversion to shrimp ponds; and (3) the land use carbon footprints of shrimp production. The mean ecosystem carbon stocks in shrimp ponds (499 ± 56 Mg C ha−1) was less than half of the relatively intact mangroves (1023 ± 87 Mg C ha−1). This equates to a potential annual emission factor over 16 years following mangrove conversion of 120 Mg CO2e ha−1 yr−1, which is similar with the total carbon loss from land conversion in freshwater tropical peat swamp forests. Inclusion of C losses from land use/cover change in a life cycle analysis (i.e., the land use carbon footprint) resulted in an estimated 2250 kg CO2-e emitted for every kg of shrimp produced in mangrove-converted ponds. Conversion of mangroves to shrimp ponds in the Mahakam Delta resulted in a carbon loss equivalent to 226 years of soil carbon accumulation in natural mangroves. Conservation of mangroves are of great value for inclusion in climate change mitigation strategies because of their large carbon stocks, the large carbon emissions generated from land use, and the potentially long period of time required to recover carbon stocks following abandonment.
Mangrove forests are important carbon sinks, and this is especially true for Indonesia where about 24% of the world's mangroves exist. Unfortunately, vast expanses of these mangroves have been ...deforested, degraded or converted to other uses resulting in significant greenhouse gas emissions. The objective of this study was to quantify the climate change mitigation potential of mangrove conservation and restoration in Indonesia. We calculated the emission factors from the dominant land uses in mangroves, determined mangrove deforestation rates and quantified the total emissions and the potential emission reductions that could be achieved from mangrove conservation and restoration. Based on our analysis of the carbon stocks and emissions from land use in mangroves we found: (1) Indonesia's mangrove ecosystem carbon stocks are among the highest of any tropical forest type; (2) mangrove deforestation results in greenhouse gas emissions that far exceed that of upland tropical deforestation; (3) in the last decade the rates of deforestation in Indonesian mangroves have remained high; and (4) conservation and restoration of mangroves promise to sequester significant quantities of carbon. While mangroves comprise only ≈2.6% of Indonesia's total forest area, their degradation and deforestation accounted for ≈10% of total greenhouse gas emissions arising from the forestry sector. The large source of greenhouse gas emissions from a relatively small proportion of the forest area underscores the value for inclusion of mangroves as a natural climate solution. Mangrove conservation is far more effective than mangrove restoration in carbon emissions reductions and an efficient pathway to achieve Indonesia's nationally determined contribution (NDC) targets. The potential emission reduction from halting deforestation of primary and secondary mangroves coupled with restoration activities could result in an emission reduction equivalent to 8% of Indonesia's 2030 NDC emission reduction targets from the forestry sector.
Mangroves are recognized valuable components of natural climate solutions (NCS) that would facilitate meeting nationally determined contributions (NDC) targets. Protection of extant mangroves coupled with efforts to restore degraded/deforested mangrove areas to become net carbon sinks would facilitate mangroves playing an outsized role in meeting Indonesia's commitment to reducing greenhouse emissions.
Mangroves sequester large quantities of carbon (C) that become significant sources of greenhouse gases when disturbed through land-use change. Thus, they are of great value to incorporate into ...climate change adaptation and mitigation strategies. In response, a global network of mangrove plots was established to provide policy-relevant ecological data relating to interactions of mangrove C stocks with climatic, tidal, plant community, and geomorphic factors. Mangroves from 190 sites were sampled across five continents encompassing large biological, physical, and climatic gradients using consistent methodologies for the quantification of total ecosystem C stocks (TECS). Carbon stock data were collected along with vegetation, physical, and climatic data to explore potential predictive relationships. There was a 28-fold range in TECS (79–2,208 Mg C/ha) with a mean of 856 ± 32 Mg C/ha. Belowground C comprised an average 85% of the TECS. Mean soil depth was 216 cm, ranging from 22 to >300 cm, with 68 sites (35%) exceeding a depth of 300 cm. TECS were weakly correlated with metrics of forest structure, suggesting that aboveground forest structure alone cannot accurately predict TECS. Similarly, precipitation was not a strong predictor of TECS. Reasonable estimates of TECS were derived via multiple regression analysis using precipitation, soil depth, tree mass, and latitude (𝑅² = 0.54) as variables. Soil carbon to a 1 m depth averaged 44% of the TECS. Limiting analyses of soil C stocks to the top 1 m of soils result in large underestimates of TECS as well as in the greenhouse gas emissions that would arise from their conversion to other land uses. The current IPCC Tier 1 default TECS value for mangroves is 511 Mg C/ha, which is only 60% of our calculated global mean. This study improves current assessments of mangrove C stocks providing a foundation necessary for C valuation related to climate change mitigation. We estimate mangroves globally store about 11.7 Pg C: an aboveground carbon stock of 1.6 Pg C and a belowground carbon stock of 10.2 Pg C). The differences in the estimates of total ecosystem carbon stocks based on climate, salinity, forest structure, geomorphology, or geopolitical boundaries are not as much of an influence as the choice of soil depth included in the estimate. Choosing to limit soils to a 1 m depth resulted in estimates of <5 Pg whereas those that included the soil profile >1 m depth resulted in global carbon stock estimates that exceeded 11.2 Pg C.
Mangroves are an important ecosystem that provides valuable social, economic, and environmental services. Indonesia has placed mangroves on its national priority agenda in an important effort to ...sustainably manage this ecosystem and achieve national climate commitments. However, mangrove management is faced with complex challenges encompassing social, ecological, and economic issues. In order to achieve the government’s commitments and targets regarding mangrove restoration and conservation, an in-depth study on and critical review of mangrove management in Indonesia was conducted herein. This work aimed to provide a comprehensive analysis of the challenges and strategic recommendations for sustainable mangrove management in Indonesia. SWOT analysis was carried out to understand the strengths, weaknesses, opportunities, and threats related to mangrove management in Indonesia. To address these gaps, we reviewed the existing policies, current rehabilitation practices, environmental challenges, and research and technology implementations in the field. We found that strategies on mangrove ecosystem protection, such as improving the function and value of mangrove forests, integrating mangrove ecosystem management, strengthening political commitments and law enforcement, involving all stakeholders (especially coastal communities), and advancing research and innovations, are crucial for sustainable mangrove management and to support the national blue carbon agenda.
Abstract
Indonesia offers a dramatic opportunity to contribute to tackling climate change by deploying natural climate solutions (NCS), increasing carbon sequestration and storage through the ...protection, improved management, and restoration of drylands, peatlands, and mangrove ecosystems. Here, we estimate Indonesia’s NCS mitigation opportunity for the first time using national datasets. We calculated the maximum NCS mitigation potential extent using datasets of annual national land cover, peat soil, and critical lands. We collated a national emissions factor database for each pathway, calculated from a meta-analysis, recent publications from our team, and available literature. The maximum NCS mitigation potential in 2030 is 1.3 ± 0.04 GtCO
2
e yr
−1
, based on the historical baseline period from 2009–2019. This maximum NCS potential is double Indonesia’s nationally determined contribution (NDC) target from the forestry and other land use sector. Of this potential opportunity, 77% comes from wetland ecosystems. Peatlands have the largest NCS mitigation potential (960 ± 15.4 MtCO
2
e yr
−1
or 71.5 MgCO
2
e ha
−1
yr
−1
) among all other ecosystems. Mangroves provide a smaller total potential (41.1 ± 1.4 MtCO
2
e yr
−1
) but have a much higher mitigation density (12.2 MgCO
2
e ha
−1
yr
−1
) compared to dryland ecosystems (2.9 MgCO
2
e ha
−1
yr
−1
). Therefore, protecting, managing, and restoring Indonesia’s wetlands is key to achieving the country’s emissions reduction target by 2030. The results of this study can be used to inform conservation programs and national climate policy to prioritize wetlands and other land sector initiatives to fulfill Indonesia’s NDC by 2030, while simultaneously providing additional co-benefits and contributing to COVID-19 recovery and economic sustainability.
Mangrove forest in Lubuk Kertang Village, West Brandan sub-district has been converted around 20 ha annually (1996–2016) into various non-forest land use. Rehabilitation can be a solution to restore ...the condition of the ecosystem so that it can resume its ecological and economic functions. This paper discusses the evaluation of mangrove rehabilitation carried out by planting 6000 propagules in December 2015 and 5000 seedlings in May 2016 with Rhizophora apiculata species in abandoned ponds. Monitoring was carried out every 6 months from 2016 to 2022. In the restored area, 11 true mangrove species and 3 associated mangrove species were found. The percentage of plants that survived after seven years was 69.42% for planting using propagules and 86.38% for planting with seedlings. The total biomass carbon stocks stored by 7-year-old plants using propagules was 51.18 Mg ha−1, while the carbon stored by planting using seedlings was 56.79 Mg ha−1. Soil carbon stocks at the planted site with propagules were 506.89 ± 250.74 MgC ha−1, and at the planted site with seedlings were 461.85 ± 102.23 MgC ha−1. The total ecosystem carbon stocks (including aboveground carbon) in the planted site using propagules were 558.07 MgC ha−1, while planting using seedlings were 518.64 MgC ha−1. The dataset and findings on the carbon storage evaluation of mangrove rehabilitation will be useful for blue carbon research community and policymakers in the context of the climate change mitigation strategy for Indonesia.
This paper provides an overview of the implementation and obstacles of watershed management, and the alternative solutions based on a synoptic review of related studies and experiences across ...Indonesia. The review found that problems in the institutional aspect were hierarchical confusion, discrepancy, and asynchrony among regulations, and weak (participation, synchronization, and coordination) among watershed management stakeholders. The weaknesses in the planning stage are integration among sectors, a lack of community participation, and limited readiness to integrate watershed planning into regional planning. Stakeholders’ involvement is also a critical factor in successful implementation of degraded watershed rehabilitation, including in peatland and mangrove areas. Failure should be minimized by providing adequate information on degraded watershed characteristics, appropriate species choices, and effective mechanical construction for soil and water conservation. Community participation as the main factor in driving watershed management should be achieved by strengthening public awareness of the importance of a sustainable watershed and providing access for the community to be involved in each stage of watershed management. Another problem is data gaps which are essential to address from the planning to evaluation stages. The gaps can be bridged by using remotely sensed data and by applying hydrological-based simulation models. Simplified criteria for watershed assessment may also be required, depending on site-specific issues and the watershed scale.
Tidal floods are one of the threats that occur in coastal areas. The impact is felt for the community, as well as other impacts felt for the surrounding ecosystem, namely the mangrove population, ...where tidal floods that continue to occur can have a serious impact on the community and mangrove vegetation because they can threaten the sustainability of the mangroves. This research uses GIS to map tidal flood inundation areas and determine their relationship with biophysical factors. Spearman correlation is used to determine the relationship between points in tidal flood areas and biophysical factors such as elevation, slope, distance from rivers and distance from the beach. The research results show that the four variable factors are related to the point of tidal flood inundation. Distance from the river greatly influences the tidal flood point in Medan Belawan District, with a correlation coefficient value of -0.100. This is because rivers act as a medium for the entry of water from the sea without any obstacles to entering the land, so when the river flow reaches its carrying capacity, sea water immediately overflows into residential areas.
Abstract
Peat fires on cleared and drained tropical peatlands continue to cause tremendous damage to their ecological functions, contribute to global warming, and reduce in health of local ...communities, where the fire incidents in 2019 and 2020 correlated with weather conditions. The research aims to determine and clarify the correlation between rainfall dynamics and the occurrence and severity of peat fires in degraded tropical peatlands in South Sumatra, Indonesia. The research was conducted by recording rainfall Indonesian Agency for Meteorology, Climatology, and Geophysics (BMKG) data, surface and peat fuel, and peat fire area primer data from 2019 to 2020. The results show that two types of weather correlate with the size of the burned area in the Ogan Komering Ilir (OKI) regency. Temporal rainfall distribution, quantity, and duration a determining factor for the transition of surface fires to peat fires, especially in the role they play in the hydrology and moisture conditions of peat and surface fuels. This study will present the effect of rainfall in the dry and wet dry seasons on peatland fires and the extent of peat fires that occurred in two years.
Background
Mangrove ecosystems exhibit significant carbon storage and sequestration. Its capacity to store and sequester significant amounts of carbon makes this ecosystem very important for climate ...change mitigation. Indonesia, owing to the largest mangrove cover in the world, has approximately 3.14 PgC stored in the mangroves, or about 33% of all carbon stored in coastal ecosystems globally. Unfortunately, our comprehensive understanding of carbon flux is hampered by the incomplete repertoire of field measurement data, especially from mangrove ecosystem-rich regions such as Indonesia and Asia Pacific. This study fills the gap in greenhouse gases (GHGs) flux studies in mangrove ecosystems in Indonesia by quantifying the soil CO
2
and CH
4
fluxes for different land use types in mangrove ecosystems, i.e., secondary mangrove (SM), restored mangrove (RM), pond embankment (PE) and active aquaculture pond (AP). Environmental parameters such as soil pore salinity, soil pore water pH, soil temperature, air temperature, air humidity and rainfall are also measured.
Results
GHG fluxes characteristics varied between land use types and ecological conditions. Secondary mangrove and exposed pond embankment are potential GHG flux sources (68.9 ± 7.0 and 58.5 ± 6.2 MgCO
2
e ha
− 1
yr
− 1
, respectively). Aquaculture pond exhibits the lowest GHG fluxes among other land use types due to constant inundation that serve as a barrier for the release of GHG fluxes to the atmosphere. We found weak relationships between soil CO
2
and CH
4
fluxes and environmental parameters.
Conclusions
The data and information on GHG fluxes from different land use types in the mangrove ecosystem will be of importance to accurately assess the potential of the mangrove ecosystem to sequester and emit GHGs. This will support the GHG emission reduction target and strategy that had been set up by the Indonesian Government in its Nationally Determined Contributions (NDC) and Indonesia’s 2030 Forest and Other Land Use (FOLU) Net Sink.