Influence of Natural Processes and Bottom Trawling in the Nepheloid Layer Structure Off Vancouver Island (British Columbia, Canada, NE Pacific)

Continental margins are transitional areas between the land and deep ocean where large amounts of particulate matter supplied, transported, ultimately deposited in sea. High-energy hydrodynamic processes such as storms, currents, or internal waves tides, well bottom trawling activities contribute to resuspension remobilization these particles. These mechanisms favor their transference from continental shelf slope maintain high concentrations water column forming nepheloid layers. The temporal evolution hydrographic structure upper off Vancouver Island (British Columbia, Canada, NE Pacific) was assessed by analyzing 4 months (from mid-August late-November 2018) sensor data Ocean Networks Canada (ONC) NEPTUNE cabled seafloor observatory. distribution during study period illustrated a well-defined turbidity consisting surface layers (SNLs) at <100 m depth associated primary secondary productivity, intermediate (INLs) 150 300 shelf-break domain, (BNLs) developed >400 depth. Moderate storm events occurred fall when more intense INLs were recorded depths. However, not all this coincidence with indicating that INL detachments modulated different sediment mechanism. Analyses fishing vessel activity revealed trawlers operated over same range INLs. Our results suggest that, combination regional presence continuous along contributes advection suspended particles, playing major role transfer