In many natural and managed forest and tree systems, pest attacks and related dieback events have become a matter of increasing global concern. Although these attacks modify the carbon balance of tree systems, their contribution to climate forcing and the relative impact of nature-based mitigation measures is seldom considered. Here, we assess the extent to which biological control protects or reconstitutes carbon sequestration capacity and storage in monoculture tree plantations globally. Specifically, we draw upon field-level assessments, niche modeling and forest carbon flux maps to quantify potential risk of carbon sequestration loss due to three globally important insect herbivores of pine and eucalyptus. Specifically, herbivory by the tree-feeding insects Sirex noctilio, Leptocybe invasa and Ophelimus maskelli conservatively reduces carbon sink capacity by up to 0.96–4.86% at the country level. For a subset of 30, 11 and nine tree-growing countries, this potentially compromises a respective 4.02%, 0.80% and 0.79% of the carbon sink capacity of their tree hosts. Yet, in the invasive range, released biological control agents can help regain lost sink capacity to considerable extent. Equally, across both the S. noctilio native and invasive range, carbon sequestration capacity is protected by resident biota to the tune of (max.) 0.28–0.39 tons of CO2 equivalent per hectare per year. Our exploratory valuation of pest-induced sequestration losses and their biodiversity-driven mitigation informs climate policy, biosecurity, and management practice.
Tag: Carbon sequestration
Mangrove-based carbon market projects: Current trends and future perspectives
Blue carbon ecosystems are among the largest carbon sinks in the world, with significant potential for carbon sequestration in their biomass, soils and sediments. Blue carbon credits offer companies the opportunity to offset their residual carbon emissions and achieve their carbon neutrality commitments. Mangrove-based carbon market projects (MbCMP) contribute greatly to the global supply of blue carbon credits in the voluntary carbon market (VCM). Thus, the current trends, challenges and opportunities intrinsic to MbCMP development, implementation and management need to be assessed on a global scale. We conducted a comprehensive systematic review and retrieved 260 articles, including 84 peer-reviewed articles and 176 gray literature from Scopus, Web of Science, Google Scholar and Google searches, from January 2010 to December 2024. In addition, we explored the databases of carbon certification standard registries to obtain up-to-date information of MbCMP. We present the results and discuss insights grouped into the following categories: (i) geographic distribution and current status of MbCMP, (ii) trends in development and growth, (iii) challenges faced, and (iv) proposed solutions to improve the quality and integrity of MbCMP. The recommendations include: (a) improving transparency and governance, (b) advancing risk management and adaptation, (c) building scientific and technical skills of stakeholders, (d) enhancing capacity building, community engagement and knowledge sharing, (e) strengthening policy support and institutions, (f) upscaling projects, (g) protecting complex and insecure land tenure systems, (h) safeguarding financial resources and equitable sharing of benefits, and (i) increasing accuracy of monitoring, reporting and verification (MRV) data. Although significant challenges remain, the reduction in global mangrove loss, driven by recent improvements in conservation, protection and restoration initiatives, provides immense optimism for the growth and sustainability of the MbCMP sector with true benefits in terms of climate change mitigation and biodiversity conservation.
A scalable, annual aboveground biomass product for monitoring carbon impacts of ecosystem restoration projects
Restoring natural ecosystems has the potential to remove billions of tons of CO2 annually through the end of the century, but rigorously measuring the climate impacts of restoration activities on the ground remains elusive. Ecosystem restoration interventions across hundreds or thousands of smallholder properties require robust above-ground biomass (AGB) products at high spatial (deca-metric: 10–30 m) resolution for annual monitoring, reporting, and verification (MRV). In addition to ongoing monitoring, historical AGB time series across the region are also necessary. Historical maps are for example needed for eligibility checks and the selection of appropriate counterfactuals, i.e., to establish a dynamic performance benchmark. We present a novel AGB product based on a recently developed foundation model leveraging progress in self-supervised learning (SSL) techniques from multi-spectral Earth Observation (EO) time series. The foundation model is non-contrastive and condenses all available spectral observations acquired within a year into a few, orthogonal and highly informative representations at 10 m (for Sentinel-2) and 30 m (for Landsat 7/8). Combined with spatially sparse Global Ecosystem Dynamics Investigation (GEDI) full-waveform measurements at two relative heights (RH95 and RH10), but otherwise without any further fine-tuning, we are able to estimate forest biomass with an RMSE of <25 Mg/ha, when validated against 38 in-situ AGB measurement sites across a range of agroforestry (cacao and oil palm) and restoration age classes. Compared to five openly available datasets – most of them not available at annual time steps – our approach reduces the RMSE by 15–55%. We demonstrate the scalability of our approach, by producing annual AGB maps covering the entire state of Para, Brazil, for the years 2013 to 2024. The approach is computationally efficient, fully self-supervised without relying on contrastive samples, and can therefore be scaled to global coverage, even under conditions of high cloudiness.
Light use efficiency (LUE) based bimonthly gross primary productivity (GPP) for global grasslands at 30 m spatial resolution (2000–2022)
The article describes production of a high spatial resolution (30 m) bimonthly light use efficiency (LUE) based gross primary productivity (GPP) data set representing grasslands for the period 2000 to 2022. The data set is based on using reconstructed global complete consistent bimonthly Landsat archive (400TB of data), combined with 1 km MOD11A1 temperature data and 1° CERES Photosynthetically Active Radiation (PAR). First, the LUE model was implemented by taking the biome-specific productivity factor (maximum LUE parameter) as a global constant, producing a global bimonthly (uncalibrated) productivity data for the complete land mask. Second, the GPP 30 m bimonthly maps were derived for the global grassland annual predictions and calibrating the values based on the maximum LUE factor of 0.86 gCm−2d−1MJ−1. The results of validation of the produced GPP estimates based on 527 eddy covariance flux towers show an R-square between 0.48–0.71 and root mean square error (RMSE) below ~2.3 gCm−2d−1 for all land cover classes. Using a total of 92 flux towers located in grasslands, the validation of the GPP product calibrated for the grassland biome revealed an R-square between 0.51–0.70 and an RMSE smaller than ~2 gCm−2d−1. The final time-series of maps (uncalibrated and grassland GPP) are available as bimonthly (daily estimates in units of gCm−2d−1) and annual (daily average accumulated by 365 days in units of gCm−2yr−1) in Cloud-Optimized GeoTIFF (~23TB in size) as open data (CC-BY license). The recommended uses of data include: trend analysis e.g., to determine where are the largest losses in GPP and which could be an indicator of potential land degradation, crop yield mapping and for modeling GHG fluxes at finer spatial resolution. Produced maps are available via SpatioTemporal Asset Catalog (http://stac.openlandmap.org) and Google Earth Engine.
Standard and Methodology for the Development and Certification of Mangrove Blue Carbon Projects in Indonesia
Mangrove blue carbon holds high economic value, making the development of investment-based projects reliant on robust standards and methodologies. The Standards and Methodologies Document for the Development and Certification of Mangrove Blue Carbon Projects in Indonesia outlines procedures for developing mangrove blue carbon projects using standards and methodologies that take into account both national regulations and internationally recognized frameworks. It details the standards for defining spatial and temporal boundaries and for carbon stock accounting for each category of mangrove blue carbon projects, presented within the context of the project development cycle.
The methodologies described include the establishment of baselines (both historical and scenario-based), calculation of greenhouse gas (GHG) emissions and removals, and approaches for integrating national and international methodologies. This document refers to several technical references such as the User Manual of the National Registry System for Climate Change Control (SRN PPI) and the Guidelines for the Certification Scheme on Greenhouse Gas Emission Reduction (SPEI), as well as national regulations including Presidential Regulation No. 98 Year 2021 and Minister of Environment and Forestry Regulation No. 21 Year 2022. In addition, it aligns with international standards such as the Verified Carbon Standard (VCS), Plan Vivo (PV), and the Emission Reduction Fund (ERF).
Financial mechanisms to support Vietnamese enterprises in investing and implementing forest carbon projects: From policy to practice
In this working paper, the authors review and analyse financial policies and mechanisms that aim to help enterprises invest and implement forest carbon projects. These include: (i) state budget expenditure policies; (ii) tax incentives; (iii) business support in investing and accessing domestic and foreign credits/grants/loans; and (iv) participation in the carbon market. The authors discuss the challenges of policy implementation and propose solutions.
Towards an effective, practical and equitable forest carbon legal framework in Vietnam: Recommendations and proposals for the Draft Decree on Forest Carbon Sequestration and Storage Services, based on a synthesis of global and Vietnamese experiences and practices
This report analyses the provisions proposed in the Draft Decree on Forest Carbon Sequestration and Storage Services (‘the Draft Decree’) and provides relevant information as well as scientific evidence in both the global and Vietnamese contexts. The aim is to help policymakers make informed adjustments that align with Vietnam’s specific circumstances while positioning the country to proactively respond to emerging trends in the future carbon market.
Prioritizing mitigation pathways in land use and food systems: A systematic framework to assess opportunities
The global food system generates substantial greenhouse gas (GHG) emissions, amounting to 13–23 GtCO₂e annually, or 23–42% (average: 31%) of the total global net anthropogenic GHG emissions. Yet, despite its importance, the food system is still rarely considered holistically in climate policies, strategies and plans. To help fill this gap, this paper develops a simple but systematic, comprehensive and integrated framework to assess and rank alternative mitigation options in land use and food systems, based on their desirability (what we should do) and feasibility (what we can do). This framework consists of 23 indicators covering the six dimensions of feasibility defined by the Intergovernmental Panel on Climate Change (IPCC), namely: the geophysical, environmental-ecological, technological, economic, sociocultural and institutional dimensions. Such a framework could help policymakers to raise the ambition of their Nationally Determined Contributions (NDCs) and climate policies by identifying and prioritizing ‘low-hanging fruits’, i.e., mitigation options that have the highest transformative potential; can be implemented the most quickly and easily; and are the best adapted to national or local conditions, priorities and needs.
Agromorphological characteristics of Irvingia gabonensis (Aubry-Lecomte ex O’Rorke) Baill. (Wild mango) and its effect on Theobroma cacao L. in traditional agroforestry systems
The study was conducted in the localities of Buyo, Duekoué, and Gueyo in western Côte d’Ivoire, within agroforestry systems that combine cocoa trees with Irvingia gabonensis. The aim was to enhance cocoa production in Côte d’Ivoire by associating it with I. gabonensis to achieve sustainable production. To achieve this goal, plots with radii of 10 and 20 m around I. gabonensis trees were established to assess diameter, height, morphological characteristics of fruits and seeds, biomass, and carbon stock. The results showed uniformity in the morphological characteristics of I. gabonensis, fruit production, biomass, and carbon stock across all localities, except for height. The vigor and pod yield of cocoa trees near I. gabonensis were reduced, likely due to lower cocoa density in its vicinity. However, its presence in cocoa plantations increased biomass production and carbon stock. I. gabonensis also stabilized the incidence of rotted and gnawed pods. Therefore, integrating I. gabonensis into agroforestry plots could be beneficial, provided that cocoa density around it is reduced to minimize its impact on cocoa vigor and yield.
Leveraging mangroves to advance climate action in Africa: Zooming in on Nationally Determined Contributions (NDCs)
Mangroves are vital for climate change adaptation and mitigation due to their efficient carbon sequestration and coastal protection roles providing often untapped opportunities for countries to enhance their national climate commitments (including the so-called Nationally Determined Contributions) under the Paris Agreement adopted at the United Nations Framework Convention on Climate Change (UNFCCC) COP21 in 2015. In Africa, several countries possess mangroves and have signed the Paris Agreement, however, the level of integration of mangrove actions into the Nationally Determined Contributions (NDCs) has not been adequately explored.
Using a systematic review methodology, 33 African countries possessing mangroves were selected and their NDCs were reviewed, scored, and ranked to assess their level of integration of mangrove ecosystems into their NDCs.
Countries like Equatorial Guinea, Nigeria, Senegal, and Sudan demonstrate commendable progress and leadership in integrating mangroves within their NDCs. However, gaps in budgetary commitments, spatial planning, and temporal specificity for mangrove actions among a majority of the countries hinder broader mangrove inclusion. The study also revealed a disconnect between research outputs and policy frameworks, where countries with increased mangrove research output in Africa failed to integrate mangrove actions into their NDCs.
To increase African countries’ resilience to climate risks and contributions to global climate goals, there is a need to increase effective collaboration between mangrove researchers, local communities, and policymakers in mangrove-possessing countries. This will bolster public education on mangroves and their inclusion of mangrove actions in their NDCs, ultimately enhancing the implementation of mangrove actions on the ground.