CableN2O · Effect of cable bacteria on N2O greenhouse gas emissions from aquatic sediments.

Nitrous oxide (N2O) is a critical greenhouse gas (GHG) and contributes to stratospheric ozone depletion. Although several microbial key players have been identified as enrolled in natural N2O production, large amounts of N2O have been produced by an overlooked and undefined process. A recent study showed the first experimental proof for N2O production by an overlooked abiotic process in sediment, stimulated by Fe(II). Recently discovered cable bacteria are globally occurring and change sediment geochemistry, providing Fe(II) and possibly nitrite, ideal precursors for N2O formation. Therefore, we hypothesis that cable bacteria stimulate N2O formation. This project, CableN2O aims to quantify the effect of cable bacteria on N2O emissions from sediments, its regulating factors, and environmental relevance in lab and field studies. The project's goals will be attained by interdisciplinary training of state-of-the-art biogeochemical techniques combined with a multidisciplinary approach based on traditionally applied methods in Geochemistry, Electromicrobiology, and Molecular Ecology. Hence, the project will primarily provide new insights on the role of cable bacteria on N2O formation, strengthening European excellence in this research field.