Natural vs. trawling-induced water turbidity and suspended sediment transport variability within the Palamós Canyon (NW Mediterranean)

Abstract Increases of water turbidity and suspended sediment transport in submarine canyons have been associated with high-energy events such as storms, river floods dense shelf cascading (DSWC), occasionally bottom trawling along canyon flanks rims. To assess the variations on column Palamós Canyon linked to both natural trawling-induced processes, an autonomous hydrographic profiler, well a near-bottom current meter turbidimeter were deployed axis (929 m depth) from February June 2017, covering closure (February) activities (March-June). Periods enhanced during mostly storms DSWC events, transporting turbid waters into canyon. In absence displayed low concentrations (~ 0.3 mg L − 1 ) until season began, when particulate matter detachments, ranging between > 3.8 , observed at depths where grounds are found. During closure, high fluxes (35–44 g 2 s sporadically registered ~ 920 depth major storm event. Smaller but more frequent increases (0.1–1.4 recorded activities. Despite these smaller fluxes, 30 days continuous activity transported total amount 40 kg similar magnitude that generated by event (50 ). Since is practiced daily basis throughout year, much larger contribution anthropogenically derived can be expected.