Terrestrial and Aquatic Carbon Dynamics in Tropical Peatlands under Different Land Use Types: A Systematic Review Protocol

Peatlands are both responding to and influencing climate change. While numerous studies on peatland carbon dynamics have been published in boreal and temperate regions for decades, a much smaller yet growing body of scientific articles related to tropical peatlands has recently been published, including from previously overlooked regions such as the Amazonian and Congo basins. The recent recognition of tropical peatlands as valuable ecosystems because of the organic carbon they accumulate in their water-saturated soils has occurred after most of them have been drained and degraded in Southeast Asia. Under disturbed conditions, their natural carbon storage function is shifted to an additional carbon source to the atmosphere. Understanding the effect of land-use change and management practices on peatlands can shed light on the driving variables that influence carbon emissions and can model the magnitude of emissions in future degraded peatlands. This is of primary importance as other peatland-covered regions in the tropics are at risk of land-use and land-cover changes. A systematic review that synthesizes the general understanding of tropical peatland carbon dynamics based on the published literature is much needed to guide future research directions on this topic. Moreover, previous studies of biogeochemical cycling in tropical peatlands have largely focused on terrestrial stocks and fluxes with little attention given to document lateral and downstream aquatic export through natural and artificial drainage channels. Here, we present a systematic review protocol to describe terrestrial and aquatic carbon dynamics in tropical peatlands and identify the influence of land-use change on carbon exchange. We described a set of literature search and screening steps that lay the groundwork for a future synthesis on tropical peatlands carbon cycling. Such an evidence-based synthesis using a systematic review approach will help provide the research community and policymakers with consistent science-based guidelines to set and monitor emissions reduction targets as part of the forestry and land-use sector