Soil organic matter (SOM) plays an essential role in biologically-mediated nutrient availability. There is, however, a lack of functionally-defined measures of SOM. We analysed C and N in particle-size, density and size-density fractions of SOM in order to identify the measures of SOM most affected by maize and legume cropping systems. Soil was collected after the eighth cropping season (4 years) from an experiment on a Kandic Rhodustalf in Kenya. Total organic C and N in whole soil (WS) were not significantly (P < 0.05) different among seven cropping systems; however, the dry wt, N content and C content of several measured SOM fractions differed among these cropping systems. The SOM fraction most affected by cropping systems was the light fraction obtained by flotation of a sand-size fraction in a silica suspension (150–3000 m and < 1.13 g cm3) and referred to as LL. The LL fraction represented 0.08% of the WS weight and accounted for 1.7 and 1.4% of the WS total organic C and N, respectively. The next SOM fraction most affected by the cropping systems was the light fraction separated by flotation of WS in NaI (density = 1.7 g cm3) and referred to as NAL. A greater (P < 0.05) dry wt of the LL fraction and greater amounts of C and N in the LL and NAL fractions resulted from either the rotation of cowpea (Vigna unguiculata) with maize or the seasonal addition of Gliricidia sepium prunings to continuous maize, than from the continuous cropping of maize with removal of crop residues. The results suggest that the LL and NAL fractions merit further examination as sensitive measures of differences in SOM.
Tag: carbon
Follow the money: Can REDD+ finance compete with established and emerging land investments in Mai-Ndombe, Democratic Republic of Congo?
Climate finance is often considered an avenue of transformational change to address deforestation. However, financial dynamics influencing forests extend beyond climate related initiatives; forest landscapes are subject to a myriad of actors and interests. This paper examines if and how REDD+ finance can lead to transformative decisions in a complex political landscape of competing land uses, interests, and financial flows in Mai-Ndombe, Democratic Republic of Congo (DRC). We employ a critical global political economy perspective to investigate inequality within global forest governance. We use a telecoupling framing combined with open-source research methods to examine public information and databases on company ownership and structures, to capture flows of finance and commodities. Our study demonstrates that, in Mai-Ndombe, climate finance incentives have limited influence in the presence of dominant interests and investments in extractive activities; particularly when mining, livestock, timber, and carbon concessions overlap, and oil exploration permits are in use by state and private sector actors. REDD+ strategies in the DRC inadvertently reinforce historical inequalities by focusing on local interventions; this overlooks persistent power relations that are visible in discursive practices, financial flows, and incentive structures centering around extractive land uses. The methods and data in this paper provide insights into how finance and investments in both climate change mitigation and industrial land use are driving land-use change and inadvertently reinforcing inequality. We encourage funders, policymakers, and researchers at the intersection of climate and forests to move beyond oversimplified narratives of who is to blame for deforestation, and instead trace the financial flows to examine who actually benefits.
New species-specific allometric models for above- and below-ground biomass and carbon content of young mangroves
Mangroves restoration plays a vital role in climate change mitigation, with carbon sequestration capability as a key indicator. However, most existing allometric models used for biomass estimation are developed from mature trees and are unsuitable for young mangroves due to limitations in the availability of predictor variables. These models rely on diameter at breast height (DBH) to predict biomass, making them inapplicable for young mangroves in the early restoration phase, which do not yet have a measurable DBH. This study develops species-specific allometric equations for estimating aboveground (AGB) and belowground biomass (BGB) of young mangroves across four species: Bruguiera gymnorrhiza, Kandelia candel, Rhizophora apiculata, and Rhizophora mucronata. Samples were collected using destructive methods along with structural measurement to develop species-specific allometric models using simple power equation and compared with existing models. Biomass distribution was highest in the stem, followed by branches and stilt-roots, then lowest in roots. Carbon content was relatively uniform among different tree components, except for lower values in roots. AGB proportion generally exceeded BGB, except in R. apiculata, with root-to-shoot ratios ranging from 0.43 to 1.31. The best AGB and BGB models showed high goodness of fit (Adj R² = 0.94–0.95 and 0.83–0.97, respectively). Validation showed species-specific performance varied among AGB models (RMSE = 0.07–0.20; MAPE = 0.15–0.25) and among BGB models (RMSE = 0.04–0.43; MAPE = 0.13–0.40). Compared to existing allometric models for mangrove saplings, these new models enhance biomass estimation accuracy for young mangroves that are essential in restoration monitoring and complement existing equations suited for mature trees. Notably, this study provides the first allometric model for K. candel in Indonesia and includes BGB estimates, which are still limited in mangroves research.
Spatiotemporal variation in Coffea canephora leaf traits and iWUE in Congo Basin forests
Understanding how plant traits vary across space and time is critical for predicting responses to environmental change. This study analyzed 179 herbarium samples of Coffea canephora collected between 1900–60 and 2016–21 across the Congo Basin. Researchers measured morphological traits (specific leaf area [SLA], stomatal size [S], stomatal pore size [SPS], stomatal density [SD], maximum diffusive conductance [gcmax]) and physiological traits (δ¹³C, δ¹⁸O isotopes, intrinsic water-use efficiency [iWUE]). Results revealed significant spatiotemporal variation: SLA and stomatal size increased over the past century, while SPS, SD, gcmax, δ¹³C, and iWUE decreased. Morphological traits reflected long-term environmental adaptation, whereas physiological traits responded to short-term drivers such as atmospheric CO₂ and precipitation. Trait correlations highlighted functional trade-offs: SLA was negatively correlated with iWUE, while S, SD, and gcmax were positively associated. These findings suggest a decoupling between morphology and physiology that may constrain photosynthetic performance under future climate change. Herbarium-based multitrait approaches prove valuable for reconstructing long-term plant responses and climate sensitivity in tropical understorey species.
Demystifying the Romanticized Narratives About Carbon Credits From Voluntary Forest Conservation
Carbon offset projects aimed at avoiding deforestation and forest degradation, generally labeled “REDD+,” are frequently promoted as a pivotal tool to mitigate climate change, promising to offer additional co-benefits for biodiversity and local communities. Despite this optimism, most positive impacts claimed by these initiatives in the voluntary carbon market (VCM) lack empirical support and are instead based on the hopeful narratives of stakeholders with clear conflicts of interest. We critically examine the scientific theories, concepts, and evidence regarding VCM’s REDD+ projects, highlighting limitations on the quantification of their purported benefits that are inherent to the current design of carbon markets. Independent studies consistently point to shortcomings in the rigor and credibility of crediting methodologies and other procedures, which market players have been slow or reluctant to address. There is accumulating evidence that projects’ climate and social impacts are often exaggerated due to a range of technical and practical shortcomings. We hope this work clarifies widespread misconceptions associated with REDD+ projects in the VCM and assists organizations and policymakers in their efforts to meaningfully mitigate climate change.
Carbon markets and food systems
Carbon markets are increasingly recognized as a central instrument of international climate cooperation, yet their potential to support the decarbonization of food systems remains largely untapped. Food systems—spanning agriculture, land use and land-use change and forestry, energy, industry, and waste—account for around one third of global anthropogenic greenhouse gas emissions, while offering substantial mitigation opportunities across production, value chains, and consumption. This paper provides one of the first comprehensive assessments of how food-system-related mitigation activities are represented in international carbon markets. Drawing on an original merged database covering more than 9,200 projects from both UNFCCC mechanisms (notably the Clean Development Mechanism) and major independent standards, it analyses nearly 4.9 GtCO₂e of issued carbon credits through a food- system lens. The study introduces a simplified typology of project scopes and types and examines the geographical, sectoral, and technological distribution of food-system-related projects. It shows that while food systems account for a significant share of credits—especially in independent mechanisms— carbon market activity remains highly concentrated geographically and skewed toward a limited number of project types, notably large-scale REDD+ and refrigeration projects. By contrast, major sources of food-system emissions at the farm gate and along food value chains—such as livestock methane, rice cultivation, food loss and waste, and household energy use—remain largely overlooked. The paper discusses the implications of these gaps for the environmental integrity and effectiveness of carbon markets and highlights the need for adapted methodologies, improved integration of small-scale projects, and greater alignment between compliance and voluntary markets. It concludes by outlining how carbon markets could more effectively contribute to food-system decarbonization while supporting sustainable development and food security.
i-Mangrove Blue Carbon Dashboard: A mangrove-based climate solutions mapping tool to support high-integrity blue actions
Key messages
- Indonesia holds one of the world’s largest opportunities for mangrove-based climate mitigation, with over 300,000 ha of degraded mangrove areas and cumulative historical emissions of 257 Mt CO₂e resulting from 24 years of mangrove loss during 2001–2024.
- Aquaculture-driven conversion remains the largest source of mangrove carbon emissions, generating emission factors higher than those from mangrove deforestation and highlighting crucial priorities for targeted intervention.
- The i-Mangrove Blue Carbon Dashboard provides the first fully integrated, transparent and spatially explicit measurement, reporting and verification (MRV) system for mangrove loss drivers, carbon emissions and restoration potential opportunity across Indonesia, forming a scientific foundation for high-integrity climate actions.
- High-integrity climate actions through mangrove blue carbon in Indonesia are potentially viable, with annual mitigation potential reaching approximately 12.24 Mt CO₂e yr–1 from avoided emissions and targeted restoration efforts.
- Adoption of the i-Mangrove Blue Carbon Dashboard strengthens implementation of Nationally Determined Contributions (NDCs), enables credible blue carbon markets and guides cost-effective investments by governments, donors and project developers.
- The dashboard provides foundational data that can be integrated into Indonesia’s carbon market infrastructure, including potential applications under Indonesia Carbon Exchange (IDX Carbon).
CIFOR-ICRAF COP30. Calls to Action
2024 marked the first year in which global temperatures exceeded the 1.5 °C threshold set by the Paris Agreement. Extreme weather and related disasters are no longer exceptional; they have become part of our daily reality. Rising heat, drought and fires are already impacting millions of lives and livelihoods, while pushing some of the world’s largest forest carbon sinks toward becoming net carbon sources.
Moving ahead with REDD: issues, options and implications
Aspecto Técnicos de las Acciones Nacionales de Mitigación Apropiada (NAMA) para los sistemas ganaderos en la región de América Latina y el Caribe [Technical aspects of Nationally Appropriate Mitigation Actions (NAMAs) for livestock systems in Latin Americ
This document provides important information about the main technical aspects of livestock NAMAs, as well as the challenges they face and some recommendations that will help them to improve. It is focused in nine countries of the LAC region(Mexico, the Dominican Republic, Guatemala, Honduras, Costa Rica, Colombia, Argentina, Uruguay and Paraguay); but more specifically in five of them, where climate actions in the cattle sector are best documented (Costa Rica, Colombia, Guatemala, Honduras and Uruguay). Based on the key aspects of organization, logic and mitigation goals, the most relevant technical aspects of the NAMA proposals were reviewed to suggest guidelines and orientation for the technical design, and for the implementation of those initiatives. The study was developed between November 2018 and February 2019, by reviewing and analyzing secondary information and consulting(remotely) with key informants from each country evaluated.