Spatial and temporal variability of downward particle fluxes on a continental slope: Lessons from an 8-yr experiment in the Gulf of Lions (NW Mediterranean)

Flux and composition of settling particles across the continental margin of the Gulf of Lion: the role of dense shelf water cascading

“…Mean composition of the non-siliciclastic fraction was 30.0% of CaCO 3 , 3.2% of OM, and 1.5% of opal (Fig. 5), quite similar values than those reported by Heussner et al (2006) during maximum fluxes over a 8-year period (31-32% CaCO 3 , 2% OM, and 1% opal), and close to the composition of the superficial sediments from the shelf and upper slope (31% CaCO 3 , 1-4% OM, and opal nearly absent or below the detection limits, Roussiez et al, 2006). (Table 2).…”

“…However, in continental slopes, where TMF values are 3 orders of magnitude higher, the pelagic flux would represent a minimum part Martín et al, 2006;Zúñiga et al, 2009). Heussner et al (2006) reviewed this issue in the GoL area and differentiated between the lateral (resuspended plus rebound) and the pelagic component of the POC flux. They found that advected POC represents, on an annual basis, up to 90% of the total flux of POC in the Lacaze-Duthiers canyon.…”

“…Actually, experiments carried out in the Western Mediterranean Sea show differences of three orders of magnitude when comparing settling particles in the slope with the open basin, underlining the importance of continental shelves as a source of material for the adjoining slope environment Martín et al, 2006;Zúñiga et al, 2009). Suspended particles on the continental shelf are mainly advected to the slope through intermediate or bottom nepheloid layers (Durrieu de Madron and Panouse, 1996), resulting in larger particulate fluxes closer to the slope bottom Heussner et al, 1999Heussner et al, , 2006.…”

Living deep-sea benthic foraminifera from the Cap de Creus Canyon (western Mediterranean): Faunal–geochemical interactions

“…The main sources of particulate matter to the shelf waters in the Gulf of Lions are: riverine discharge, atmospheric dust transport (primarily Saharan dust), marine biological production and particle resuspension during storms and cascading events (Heussener et al, 2006). The Rhône river is the main supplier of freshwater and sediment of the Gulf of Lions.…”

Trophic state of benthic deep-sea ecosystems from two different continental margins off Iberia

“…Mechanisms of particle transfer to deep continental margins depend not only upon particle sedimentation from the upper ocean, but also upon a wide array of processes, including down slope and down canyon transport, rebound of re-suspended particles and episodic events such as sediment laden flows and DSWC Heussner et al, 2006;de Stigter et al, 2007). Altogether, these factors drive distribution and accumulation of organic matter in surface sediments of continental margins.…”