Potential impact of sea level rise related salinization on lowland tropical coastal peatlands

forthcoming

Sea level rise (SLR) poses risks of flooding and salinization to coastal ecosystems. At present, research on SLR impacts still heavily focuses on saline ecosystems (e.g., mangroves, saltmarshes), despite the impact of salinization being particularly dire for freshwater ecosystems. Southeast (SE) Asian coastal peatlands are freshwater wetlands playing important role in tackling the triple planetary crisis: climate change, biodiversity loss and pollution. Mainly located in low-lying coastal plains, SE Asian peatlands are highly vulnerable to the impacts of SLR. My recent research indicates that SLR-induced salinization could lead to catastrophic fires by promoting mass peat swamp forest mortality, thus increasing dead fuel availability. However, SLR impacts on SE Asian peatland ecosystem structure and functioning remain severely understudied to date. The SaLtedPeat project aims to pioneer the timely exploration of the impacts of SLR, particularly salinization, on coastal forested peatlands of SE Asia. Within this project, my team and I will explore the historical relation between SLR and severe fire occurrences in SE Asian coastal peatlands using long-term ecological studies as well as analyse the contemporary land-sea gradients in peatlands through field observations. We will mimic the impact of SLR-related salinization on peatland vegetation and peat physicochemical properties by performing a salt-addition experiment, and model changes in peatland properties and C stocks following SLR and projected precipitation changes. The SaLtedPeat project will unravel the potential (hidden) impacts of SLR on SE Asian peatlands, provide the first assessments of salinity (in)tolerance of peat swamp forests, advance knowledge on the ecosystems’ spatiotemporal variability, and estimate potential C loss following SLR. The project outputs will also assist in developing solutions to overcome the triple planetary crisis, i.e., (i) keep or grow C stocks, (ii) maintain habitat for biodiversity and (iii) avoid fire-induced air pollution.