Acronym ABIDES
Category
Fisheries
Title Assesment of bottom-trawling impacts in deep-sea sediments Programme National Programme
Instrument (FP6)
Contact Type (FP7)
Strand (Interreg)
NA
Theme (FP7)
Activity Area (FP6)
Regional Area (Interreg)
Action (COST)
NA
Specific Programme (FP7)
NA
Funding source National Coordinator NA Coordinator email NA
Coordinator institution
CSIC - Spanish National Research Council (Spain)
Institutions involved
UNICA - University of Cagliari (Italy) ,
Start year 2016 End year 2018 Funding (€) € 235,950 Website NA Summary The proposed research project focuses on the study of contemporary sedimentary processes associated to the impact of bottom trawling activities on the deep seafloor. The disturbance of deep-sea environments caused by this fishing practice is considered to be notably higher than all other anthropogenic pressures combined, given its intensity, recurrence and wide geographical distribution. Although the impacts of trawling on coastal and shelf environments have been investigated in the past from the sedimentary point of view, up to date, very few studies have addressed the role of this fishing practice on slope environments, where background energy levels controlling natural sedimentary processes are generally low and where the associated benthic ecosystems are less resilient and more vulnerable. Therefore, the main goal of this project is to improve our knowledge of the contemporary sediment erosion, transport and accumulation processes driven by this anthropogenic activity, with the aim to assess the magnitude of the associated impacts in continental slope environments and to provide support for mitigation efforts towards the development of sustainable fisheries. To accomplish this, during the project we will record time series of currents, suspended sediment concentrations and particle fluxes by means of several instrumented mooring deployments nearby present heavily trawled sites. At the same time, we will collect hydrographic data and bottom and suspended sediment samples during scheduled oceanographic cruises in open-slope and submarine canyon regions, following a cross-margin approach based on the bottom trawling footprint during the past 10 years. Additionally, we will conduct a morphological and seabed habitat characterization of the continental slope regions that have (and have not) been intensively trawled during decades, both at small- and large-scale with the aim to evaluate the “seafloor integrity”. The main study area will be the nw Mediterranean continental margin, where a bottom trawling fishery has been operating for decades and a good knowledge of the current bottom-trawling footprint exists. The proposed specific objectives of the project are: 1) to monitor the near-bottom sediment transport processes within trawled submarine canyon environments and identify the contribution of this anthropogenic activity to the sediment fluxes; 2) to identify the formation and evolution of bottom and intermediate nepheloid layers in the water column, as indicators of preferential paths for trawling-induced particle resuspension and advection; 3) to evaluate the surface sediment erosion generated by trawling in the upper continental slope region and determine cross-margin trends caused by the presence of major fishing grounds; 4) to investigate changes in sediment accumulation rates within submarine canyon axes and evaluate the formation of anthropogenic depocenters; 5) to quantify the role of bottom trawling activities in the alteration of organic carbon budgets in the sedimentary record; 6) to determine the small-scale morphological changes and the impact caused by trawling gear on the seafloor habitats through direct visual observations; and 7) identify large-scale morphological changes caused by persistent trawling activities over major fishing grounds of the study area using detailed swath multibeam bathymetries, as well in other trawled regions along the Spanish continental margin where bathymetric information already exists.
Keywords
Sustainability;
Trawling;
Physical disturbance;
Environmental impact;
Marine Region
53
Northern Spain (GSA 6)
49
Gulf of Lions (GSA 7)
2
Marine Region Map
