Gypsum Dose-Response in Peat Microbial Communities

A GGR-Peat Flexible Fund Project

Led by: RSPB. Project partners: FWAG SW and Moor SW Ltd.

Degraded or drained peatlands emit high levels of carbon dioxide as exposed organic material decomposes. Rewetting curbs these emissions, but wet peat naturally emits methane, a potent greenhouse gas. Effective peatland management therefore requires approaches that support carbon sequestration while also limiting methane production.

This project examines sulphate addition—delivered as gypsum—as a method for shifting microbial activity away from methane production. Although the mechanism is known, the amount of sulphate needed to achieve low-methane conditions, and how this varies with peat chemistry, remains unclear.

The research will determine dose-response relationships between sulphate levels and microbial community outcomes across different peat types. Findings will clarify how peatland greenhouse gas balances are likely to vary regionally and will help prevent unnecessary or excessive sulphate additions. This evidence will support effective, targeted strategies to manage wet peatlands for greenhouse gas removal.