Simulating carbon accumulation and loss in the central Congo peatlands

Area of Science:

• Earth and Environmental Sciences
• Climate Science
• Ecology

Background:

• Central Congo Basin peatlands store approximately 29 billion tonnes of carbon.
• Understanding peat carbon dynamics and climate change vulnerability is limited.

Purpose of the Study:

• To model peat carbon accumulation and loss in a tropical peatland.
• To identify key controls on peatland carbon dynamics.
• To assess the vulnerability of peat carbon stores to climate shifts.

Main Methods:

• Development of the DigiBog_Congo model for tropical peatland simulation.
• Simulation of peat carbon accumulation and loss over ~20,000 years.
• Comparison of model age-depth curves with palaeoenvironmental reconstructions.

Main Results:

• Model simulations align well with palaeoenvironmental data.
• Surface wetness and slow anoxic decay are primary controls on peat accumulation.
• A drying phase ~5200 years BP led to significant carbon loss (57% of stock) over millennia.

Conclusions:

• Rainfall variability alone can trigger catastrophic, long-term peat carbon loss.
• Tropical peatlands are highly vulnerable to climate change-induced drying.
• The model provides a framework for assessing future climate and land-use impacts on peat carbon.