Most forest carbon projects have “mixed, negligible or negative impacts” on ecological integrity
“Results highlight fundamental shortcomings of these climate solutions that limit their ability to safeguard healthy ecosystems and sequester carbon.”
A new study, published in Nature Climate Change, looks at whether carbon projects aimed at reducing emissions from deforestation also benefit forest ecosystems. Here’s the abstract:
Reducing deforestation is proposed as a global climate action, yet it remains unclear whether carbon projects based on such interventions also maintain forests’ ecological conditions. Here we evaluate 133 projects against matched controls using five ecological-integrity indicators, to show that most projects have mixed, negligible or negative impacts relative to control areas. Results highlight fundamental shortcomings of these climate solutions that limit their ability to safeguard healthy ecosystems and sequester carbon.
The study was written by Kelly Ong, Tao Chen, Zhimin Chen, and Yiwen Zeng of the Nanyang Technological University in Singapore, and Carlos T. Pérez-Brito of the World Bank.
The researchers compiled data for 196 forest carbon projects. They compared the project areas with matched controls in the surrounding areas in the same biome. They excluded a 10-kilometre zone around each project area to account for local-scale leakage (where forest destruction is displaced from the project area, to the area immediately around the project).
Of the 196 projects, the authors write, “133 achieved good post-matching balance (standardized mean differences (SMD) <0.25) and were large enough to support pixel-level matching and were retained for analysis”. This number was subsequently reduced to 116 projects for which the researchers had “sufficient data to make direct comparisons between avoided deforestation project areas and unprotected forests”.
They used five indicators to evaluate the ecological integrity of each project in comparison to control areas:
biodiversity intactness index (community-level response to human
pressures),
forest landscape integrity index (measures anthropogenic
pressures and degradation intensity),
forest fragmentation (quantifies structural fragmentation based on patch configuration),
canopy height (vertical structure and forest age),
and GHG net flux (indicator of ecosystem function and carbon permanence).
Mixed, negligible or negative impacts
Of the 116 projects, only nine (8%) showed positive effects across all five ecological-integrity indicators.
29 projects (25%) showed positive effects for at least one ecological-integrity indicators, with all remaining indicators showing no significant differences. “This can be attributed to the carbon-centric design of most accounting frameworks,” the researchers write, “which prioritizes carbon storage over maintenance of ecological integrity.”
13 projects (11%) in New South Wales, Australia show no significant differences in any ecological-integrity indicators. The authors note that these projects are in areas with “low agricultural productivity and limited human activity”. In other words, these forest carbon projects faced very low risk of deforestation.
46 projects (40%) show a mix of positive, negative, and non-significant results over the five ecological-integrity indicators.
19 projects (16%) showed “poorer ecological conditions than the surrounding unprotected forests”.
The authors point out that,
[C]arbon finance can sometimes exacerbate existing social tensions, reinforcing the need for strong safeguards. For example, the Purus Project (VCS963) in Brazil faced unresolved land tenure issues and lacked formal regulatory mechanisms to manage disputes, undermining enforcement capacity and community support despite achieving Climate, Community and Biodiversity certification. These challenges contributed to continued deforestation and conflict, limiting ecological gains despite carbon finance inflows.
The authors conclude that forest carbon projects “can maintain ecological integrity under specific conditions” but “their performance is inconsistent overall”.
Oddar Meanchey as an example of “ecological integrity”?
The authors write that improved ecological integrity is “often linked to approaches that emphasize community engagement, local participation and livelihood-improvement programmes”.
More broadly, success also depends on governance conditions, including secure land tenure, effective regulatory frameworks and socio-political contexts shaped by population pressures and conflict.
That seems reasonable.
However, as an example of these approaches, the authors refer to the Oddar Meanchey REDD project in Cambodia.
The project has completely failed to prevent deforestation. Large areas of community forests that were part of the REDD project were cleared by the Cambodian military. In 2014, Shalmali Guttal of Focus on the Global South sent a series of photographs of the destruction to REDD-Monitor:
The Oddar Meanchey REDD project consisted of 13 community forest areas. Of these, only one succeeded in preventing deforestation.
Timothy Frewer wrote his PhD dissertation at the University of Sydney on the Oddar Meanchey project, conducting almost 300 interviews as part of his research. Frewer notes that the one community forest that prevented deforestation is run by a “charismatic monk” who “governs the forest in a near-despotic fashion”.
The authors of the new study in Nature Climate Change refer to a 2014 paper written by Ian Baird of the University of Wisconsin-Madison to support their claims about the Oddar Meanchey project involving community engagement and local participation.
But Baird’s paper is quite critical of the Oddar Meanchey project. Baird notes that “one of the main structural weaknesses of the project is that it has not been able to provide locals with secure long-term tenure, or access, over forests, only 15-year agreements that provide limited community control”.
These agreements could be revoked at any time by the Forest Administration and villagers “have to organize community forests following the FA’s framework”. Baird adds that, “Communal land tenure for agricultural lands has not been established in Oddar Meanchey . . . ”.
Baird also writes that “there have been considerable problems” with the REDD project, including the clearing of “large amounts of forests in the REDD project area” by the Cambodian military, “causing so much damage to the forest that some feared the whole REDD project could be derailed as a result”.
Baird concludes that,
[I]f we assess this project using the concepts of access and exclusion, it can be concluded that it has been unsuccessful, as communities have not achieved secure long-term access to their resources, and they are having increasingly serious problems excluding others from encroaching on their forests.
The Oddar Meanchey REDD project has not sold any carbon credits since 2015. The project’s status is currently listed on Verra’s registry as “Late to verify.”