The protection, management and restoration of vegetated ecosystems on land and in the ocean (‘natural climate solutions’) can be a useful strategy for reducing net greenhouse gas emissions to help limit global warming. Their potential contribution to reducing net emissions has led to the development of policies and financial incentives for their protection and restoration. These have in turn created a set of expectations among some stakeholders, and interest in expanding these to encompass other ecosystems. However, there are specific rules about how abatement is calculated in international policy and climate finance, and the frameworks and terminology associated with them are often complex. This can be a barrier to stakeholders who want to leverage the potential of natural climate solutions, sometimes leading to incongruence between realised and anticipated benefits. In this article, we attempt to outline some of the key international policy and carbon market frameworks for coastal ‘blue carbon’ ecosystems, and the extent to which different ecosystems are accommodated. Currently, among the coastal ecosystems, only mangrove forests, seagrass meadows, and tidal marshes are typically considered in international policy and carbon market frameworks. The defining feature of these ecosystems is that the foundation species are plants that grow in sediment (soil). They are the only coastal ecosystems currently included in IPCC guidelines for national greenhouse gas inventories, and in compliance and voluntary carbon markets. There is interest in potentially including other marine ecosystems, such as kelp forests and unvegetated tidal flats, into carbon accounting frameworks, but there are unresolved questions about whether sequestration and storage of carbon by these ecosystems meets the rigorous standards required. Voluntary carbon markets have greater flexibility than mechanisms linked to national greenhouse gas inventories, and so might be early implementers of expanding methods to include other ecosystems. Incorporating coastal ecosystems into national greenhouse gas inventory is a useful action countries can take that will likely help generate incentives for protection and restoration of these important ecosystems.
Tag: Carbon sequestration
How do REDD+ projects contribute to the goals of the Paris Agreement?
Hundreds of projects to reduce emissions from deforestation and forest degradation and enhance carbon stocks (REDD+) are implemented globally, many by non-governmental organizations (NGOs) or for-profit companies. Yet, at the global level, the Paris Agreement focuses on jurisdictional (national and subnational) REDD+. We ask: (1) How much can REDD+ projects contribute to achieving national and international climate objectives? (2) What are the issues in integrating REDD+ projects into national carbon accounting? Our snapshot of 377 REDD+ projects covering 53 million ha in 56 countries is based on data from the International Database on REDD+ Projects (ID-RECCO) supplemented with new data on projects’ accounting methods. The number of new REDD+ projects declined steadily from 45 new projects in 2011 to five in 2019. We examined 161 certified projects that started between 2007 and 2017; 96 of these could sell carbon credits in voluntary carbon markets by 2020 and spent on average 4.7 (± 2.4) years between project start and sales in voluntary carbon markets. Globally, REDD+ projects claim to reduce an average of 3.67 tCO2e/ha annually. This figure – combined with projects limited coverage – implies that projects need to be upscaled more than 40x to fulfil the potential contribution of tropical and subtropical forests towards limiting global warming to well below 2oC. Compared to the national carbon accounting methods, most projects in Colombia, Indonesia and Peru (63 of 86) use at least one different carbon accounting parameter. Carbon accounting inconsistencies across levels need to be addressed. Overall, the argument for REDD+ projects lies in the emissions reductions they can achieve, diversifying participation in REDD+ and providing non-carbon benefits to local communities, potentially leading to broader support for climate action.
Long-term accumulation of macro- and secondary elements in subtropical treatment wetlands
The Everglades Stormwater Treatment Areas (STAs) are a complex of large constructed wetlands that are an integral component of the State and Federal efforts to restore the Everglades ecosystem. The overall objective of this study was to determine the accumulation rates of macro-elements including carbon (C), nitrogen (N), phosphorus (P), sulfur (S), and associated secondary elements including calcium (Ca), magnesium (Mg), aluminum (Al), and iron (Fe) in two Everglades STAs over their periods of operation. The study was conducted in STA-2 with parallel flow-ways consisting of emergent aquatic vegetation (EAV) and submerged aquatic vegetation (SAV) and the Western flow-way of STA-3/4 with EAV and SAV cells operated in series. Elemental accumulation rates were determined in the unconsolidated surficial sediments (floc) and recently accreted soil (RAS) that have accumulated on top of the antecedent soil over the 14- and 10-yr periods of operation for STA-2 and STA-3/4, respectively. Flow-ways with SAV were more efficient than EAV in accreting mineral matter, resulting in increased bulk density and higher accumulation rates of elements. Average C accumulation in the floc and RAS of SAV flow-ways was 320 g·m−2·yr−1 with approximately equal proportions of inorganic and organic C, while in the EAV flow-ways accumulation rates of C ranged from 116 to 147 g·m−2·yr−1 with mostly organic C. Phosphorus accumulation rates were approximately 2–3 times higher in SAV than in EAV flow-ways. Differences in accumulation of elements between SAV and EAV were largest for Ca with 17–42 times more Ca in SAV than EAV systems. This suggests that in the SAV systems, possible occlusion of macro-elements and metals during CaCO3 precipitation facilitated accretion of material with high mineral content. In EAV, biomass turnover and associated biotic processes regulated organic matter accumulation rates. The spatial accumulation patterns of P, C, and N in the EAV areas of STA-2 and STA-3/4 were similar to those observed in the EAV areas of the natural wetlands in Water Conservation Areas, suggesting that constructed wetland systems function similarly to natural wetlands dominated by EAV areas in retaining and storing macro- and secondary elements.
Combined effects of shade and drought on physiology, growth, and yield of mature cocoa trees
Climate models predict decreasing precipitation and increasing air temperature, causing concern for the future of cocoa in the major producing regions worldwide. It has been suggested that shade could alleviate stress by reducing radiation intensity and conserving soil moisture, but few on-farm cocoa studies are testing this hypothesis. Here, for 33 months, we subjected twelve-year cocoa plants in Ghana to three levels of rainwater suppression (full rainwater, 1/3 rainwater suppression and 2/3 rainwater suppression) under full sun or 40 % uniform shade in a split plot design, monitoring soil moisture, physiological parameters, growth, and yield. Volumetric soil moisture (ϴw) contents in the treatments ranged between 0.20 and 0.45 m3m−3 and increased under shade. Rainwater suppression decreased leaf water potentials (ѱw), reaching −1.5 MPa in full sun conditions indicating severe drought. Stomatal conductance (gs) was decreased under the full sun but was not affected by rainwater suppression, illustrating the limited control of water loss in cocoa plants. Although pre-dawn chlorophyll fluorescence (Fv/Fm) indicated photoinhibition, rates of photosynthesis (Pn) were highest in full sun. On the other hand, litter fall was highest in the full sun and under water stress, while diameter growth and carbon accumulation increased in the shade but was negatively affected by rainwater suppression. Abortion of fruits and damage to pods were high under shade, but dry bean yield was higher compared to under the full sun. The absence of interactions between shade treatments and rainwater suppression suggests that shade may improve the performance of cocoa, but not sufficiently to counteract the negative effects of water stress under field conditions.
Natural and anthropogenic impacts on mangrove carbon dynamics: a systematic review protocol
The mangrove ecosystem serves as a vital habitat for coastal flora and fauna while playing a crucial role in storing and sequestering carbon as part of global carbon cycles. Therefore, it is imperative to evaluate the carbon dynamics, encompassing storage
Carbon stocks of Geramo forest, the western escarpment of the rift valley of Ethiopia
Forests play a vital role in the global carbon balance and combating global climate change by sequestering and retaining carbon from the atmosphere in their biomass and soil. Thus, this study aims to estimate the carbon stocks in the biomass and soil along with various environmental factors in the Geramo forest in southern Ethiopia. Ninety-six plots (20 × 20 m2) were laid at a distance of 250 m along 16 line transects that were laid 300 m apart. Five 1 × 1 m2 subplots (4 at the corner and 1 at the center) were laid inside each main plot for LHG and soil data collection. The results revealed that the estimated total carbon stocks and mean carbon stock densities of the study forest were 57994 Mg h−1and 604 ± 344 Mg h−1, respectively, with a mean CO2 equivalent of 2217 ± 1262 Mg h−1. This result indicates the remarkable role of the Geramo forest in carbon stock and sequestration potential compared with other remnant forests in Ethiopia. Thus, the Geramo forest plays a crucial role in climate change mitigation through carbon sequestration, and hence, this forest can generate carbon credits as financial benefits to the nearby population in the future. The results also revealed that anthropogenic disturbances were negatively associated with the carbon stocks of the forest. Therefore, sustainable forest conservation activities are needed to conserve forest resources, protect the forest from growing anthropogenic disturbances, and sustain its current global climate change mitigation and adaptation benefits.
Applying volcanic ash to croplands – The untapped natural solution
A nature-based soil security solution is proposed. In countries with active volcanoes, such as Indonesia, volcanic ash could be used to supply nutrients and reduce CO2 from the atmosphere. The weathering can draw CO2 from the atmosphere; in addition, volcanic ash with 0% carbon can turn into soils with around 10% organic carbon. In Indonesia, soils of volcanic origin cover about 31.7 million ha or 17% of its land area. Frequent volcanic eruptions made volcanic ash or tephra readily available. However, tephra is not widely used and has not been adequately investigated as a soil amendment to sequester carbon. This paper calculates the magnitude and opportunity of CO2 drawdown potential from volcanic materials produced annually in Indonesia. In years with significant volcanic eruptions, the subsequent withdrawal will be 100–200 Mt CO2 or 20–40% of the country’s fossil fuel emission. The CO2 captured when volcanic materials weather is part of the global carbon cycle and is influenced by land-use decisions. Currently, volcanic ash is often eroded and rapidly transferred to aquatic systems. In relevant landscapes, actively managing this untapped resource is more feasible than external basalt applications as volcanic ashes do not need to be ground, can soak up significant amounts of carbon from the atmosphere, and build fertile soils that supply an abundance of nutrients to achieve food and soil security. Volcanic ash needs to be included in carbon accounting and its management could be part of emission reduction strategies.
Carbon Sequestration Potential of Agroforestry Systems in Degraded Landscapes in West Java, Indonesia
When restoring degraded landscapes, approaches capable of striking a balance between improving environmental services and enhancing human wellbeing need to be considered. Agroforestry is an important option for restoring degraded land and associated ecosystem functions. Using survey, key informant interview and rapid carbon stock appraisal (RaCSA) methods, this study was conducted in five districts in West Java province to examine potential carbon stock in agroforestry systems practiced by smallholder farmers on degraded landscapes. Six agroforestry systems with differing carbon stocks were identified: gmelina (Gmelina arborea Roxb.) + cardamom (Amomum compactum); manglid (Magnolia champaca (L.) Baill. ex Pierre) + cardamom; caddam (Neolamarckiacadamba (Roxb.) Bosser) + cardamom; caddam + elephant grass (Pennisetum purpureum Schumach.); mixed-tree + fishpond; and mixed-tree lots. Compared to other systems, mixed-tree lots had the highest carbon stock at 108.9 Mg ha−1. Carbon stock variations related to species density and diversity. Farmers from research sites said these systems also prevent soil erosion and help to restore degraded land. Farmers’ adoption of agroforestry can be enhanced by the implementation of supportive policies and measures, backed by scientific research.
Reduction of global warming potential vis-à-vis greenhouse gases through traditional agroforestry systems in Rajasthan, India
Tree-based systems in arid region of India are an integral part of livelihood and environment security. Traditionally, the maintenance of scattered trees on farm to reap several tangible and intangible benefits is a way of life. Presently, these systems are often known as low-hanging fruit and become a key weapon to fight climate change evil by offsetting greenhouse gas (GHG) emission through carbon sequestration. Therefore, to quantify the offsetting potential of GHG emission and area occupied by these tree-based systems in Rajasthan was undertaken. The study was carried out into two major aspects: estimation of agroforestry area using satellite remote sensing data, and to estimate the carbon sequestration potential of existing agroforestry by using dynamic CO2FIXv3.1 model for a simulation period of 30-years in five districts (20% sampling), namely, Bikaner, Dausa, Jhunjhunu, Pali and Sikar from Rajasthan, India. The estimated area under agroforestry in Rajasthan was 1.49 million ha. The findings revealed that the major tree species existing on farmer’s field were Prosopis cineraria, Tecomella undulata, Capparis decidua, Acacia tortilis, Prosopis juliflora, Azadirachta indica and Ziziphus mauritiana with an observed number of trees in selected districts varied from 1.40 to 14.90 ha−1(with average tree density of 9.71 ha−1). The total biomass (tree + Crop) varied from 2.22 to 19.19 Mg ha−1, whereas the total biomass carbon ranged from 1.00 to 8.64 Mg C ha−1. The soil organic carbon ranged from 4.51 to 16.50 Mg C ha−1. The average estimated carbon sequestration and mitigation potential of the agroforestry were 0.26 Mg C ha−1 year−1and 0.95 Mg CO2 eq ha−1 year−1 on farmers’ field of Rajasthan. At the state level, the reduction of GHG emission potential of agroforestry was found to be 1.42 million tonnes annually, which helps to cut carbon footprint and achieve targets of Paris agreement.
Carbon Stock Assessment in Peatland in North Kalimantan
The aim of the project is to assess and provide data on the aboveground and belowground carbon stock at the plot level in the peatland of North Kalimantan. In particular, the assessment is focused on areas that are not under any concessions or permit for management (non-permit) of secondary forest and shrub. The data is crucial as the basis for estimating carbon emission from land use/cover and land use/cover changes.