Impacts of bottom trawling on carbon cycling in the seafloor: a case study in the NW Mediterranean Sea

Fisheries play a vital role in providing food to communities worldwide. However, demersal fisheries in particular, which operate along the seafloor, have significant impacts on marine ecosystems. In addition to the threat posed to fish populations and benthic communities, the continuous contact of trawling gear also affects sedimentary biogeochemical processes, releasing carbon through mixing and erosion. Marine sediments on continental margins are important carbon sinks, sequestering carbon away from the atmosphere over long timescales. However, the fate of the carbon disturbed via bottom trawling remains largely unknown. Here I will discuss a case study investigating the impacts of bottom trawling on sedimentary carbon cycling in Palamós Canyon in the northwest Mediterranean Sea. In addition to more traditional methods, we apply radiocarbon and stable carbon isotope measurements and chemical characterization to sediments and porewaters in order to assess the biogeochemical implications of disturbing the seafloor.