Peatlands Cover Just 3% of Earth but Hold the Key to Climate Action, Scientists Say

Peatlands may be among the most overlooked ecosystems on the planet, yet their importance to the global climate system is difficult to overstate. Covering just three percent of the Earth's land surface, these waterlogged landscapes store approximately twice as much carbon as all the world's forests combined, making them one of the most powerful natural carbon sinks in existence. Now, a landmark study published in Communications Earth and Environment has identified the most pressing unanswered scientific questions about peatlands, providing a comprehensive roadmap to guide future research and policy. Led by researchers from the University of Exeter and involving scientists from institutions around the world, the paper argues that addressing these knowledge gaps is essential for effective climate action in the decades ahead.

Peatlands form over thousands of years as dead plant material accumulates in waterlogged conditions where decomposition is slowed by the lack of oxygen. This process creates thick layers of organic soil, known as peat, that can reach depths of several meters. The carbon stored in these deposits has accumulated over millennia, representing an enormous reservoir of ancient atmospheric carbon dioxide that has been locked away from the climate system. Globally, peatlands are estimated to contain between 500 and 700 gigatons of carbon, roughly equivalent to 60 years of current global fossil fuel emissions. When peatlands are drained, burned, or otherwise degraded, this carbon is released back into the atmosphere, transforming these ecosystems from carbon sinks into significant carbon sources.

Despite their outsized importance, peatlands remain among the least studied and least protected ecosystems on Earth. The new study identified key research priorities through a collaborative process involving more than 200 peatland scientists, policymakers, and land managers from over 40 countries. The resulting list of priority questions spans topics ranging from basic peatland ecology and hydrology to the socioeconomic dimensions of peatland conservation and restoration. Among the most urgent questions is how tropical peatlands, which are concentrated in Southeast Asia, the Congo Basin, and the Amazon, will respond to continued warming and land use change. Tropical peatlands store vast amounts of carbon but are under severe threat from agricultural expansion, particularly for palm oil and pulpwood plantations.

The study also highlights critical uncertainties about the role of peatlands in methane emissions. While intact peatlands are net carbon sinks over long timescales, they are also significant natural sources of methane, a greenhouse gas that is approximately 80 times more potent than carbon dioxide over a 20 year period. Understanding the balance between carbon storage and methane release is essential for accurately assessing the net climate impact of peatland conservation and restoration efforts. Some research suggests that rewetting drained peatlands, while beneficial for long term carbon storage, can temporarily increase methane emissions as waterlogged conditions are restored. The scientists stress that more detailed monitoring and modeling are needed to resolve these complexities and provide clear guidance to policymakers.

Restoration of degraded peatlands has emerged as one of the most cost effective strategies for climate change mitigation, but the science underpinning restoration practices remains incomplete. The study notes that while there is growing political momentum behind peatland restoration, with countries such as the United Kingdom, Germany, and Indonesia launching major rewetting programs, the ecological outcomes of these efforts vary widely depending on local conditions. Questions about which restoration techniques work best in different peatland types, how long it takes for restored peatlands to recover their carbon sink function, and what happens to biodiversity during the restoration process remain largely unanswered. The researchers emphasize that without a stronger evidence base, well intentioned restoration efforts risk falling short of their climate goals or producing unintended consequences.

The paper concludes with a call for substantially increased investment in peatland science, monitoring, and international cooperation. The researchers note that peatlands have historically received a fraction of the research funding and policy attention devoted to forests, despite their comparable importance as carbon stores. They argue that closing the knowledge gaps identified in the study could unlock significant climate benefits while also supporting biodiversity, water quality, and the livelihoods of communities that depend on peatland ecosystems. With global temperatures continuing to rise and pressure on peatlands intensifying from both climate change and human land use, the window of opportunity to protect these remarkable ecosystems is narrowing rapidly.