Under the surface: Bioturbation as a driver of ecological interactions involved in methane and nitrous oxide cycling and implications to coastal carbon sinks

This 4-year project seeks to quantify how bioturbation—the activity of burrowing animals in sediments—drives the dynamics of methane (CH4) and nitrous oxide (N2O) emissions in coastal ecosystems, and its implications for the capacity of benthic habitats to act as carbon (C) sinks. Our work is organized into 4 work packages (WPs) to address this from multiple scales and dimensions.

WP1 explores bioturbation´s role in promoting CH4 ebullition and its escape from microbial filters, an important mechanism explaining why costal ecosystems are hotspots for marine CH4 and N2O emissions.

WP2 delves into the effects of bioturbation on microbial processes that control CH4 and N2O cycling in marine sediments employing mesocosm experiments to quantify the interactions between fauna and microbes.

WP3 builds on this by incorporating virus-bacteria interactions´ influence on CH4 and N2O dynamics, and how they are driven by bioturbation.

Finally, WP4 focuses on different coastal habitats, assessing bioturbation´s broader effects on GHG dynamics in situ and the efficacy of these ecosystems in C sequestration.

By integrating ecological, biogeochemical, and molecular methods, the project aims to provide novel insights into the role of bioturbation in coastal CH4 and N2O dynamics and how it mediates how benthic ecosystems sequester C.

It will to refine our understanding of coastal ecosystems´ role in global C cycling and inform strategies for enhancing the resilience and of coastal habitats.