Humanity’s physical disturbance of the coastal seafloor has expanded considerably in recent decades through dredging, bottom trawling and more frequent severe storms. The natural ‘leak’ in the carbon cycle from burial of vast quantities of carbon in sediments and the removal of harmful persistent organic pollutants from aquatic ecosystems are essential services provided by sediments. Largescale seafloor disturbance can potentially release previously buried carbon to water and the atmosphere and also expose humans and ecosystems to harmful pollutants. This issue has received little research attention and is a blind spot for planners and policymakers. In this project, we will use bays and estuaries in the west and northwest of Ireland as testbeds to characterize carbon at the molecular level, quantify carbon pools being released from disturbed and pristine sediments and assess whether more ancient carbon and previously buried persistent organic pollutants are being released from sediments. This project is critical and timely; if we reveal a major threat to our coastal carbon cycle and ecosystems, we will help with more effective planning of future human marine coastal activities and inform climate action plans to ensure we keep this carbon in the ground.
