2024-03-28T14:00:49Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/270402020-11-12T08:22:29Zcom_10261_123com_10261_8col_10261_376
2010-08-12T12:14:28Z
urn:hdl:10261/27040
Evidence of sediment gravity flows induced by trawling in the Palamós (Fonera) submarine canyon (northwestern Mediterranean)
Palanques, Albert
Martín, Jacobo
Puig, Pere
Guillén, Jorge
Company, Joan B.
Sardà, Francisco
Submarine canyon
Sediment gravity flows
Trawling
Turbidity
Northwestern Mediterranean
Catalonia
14 pages, 9 figures
Three mooring arrays were deployed in the Palamós Canyon axis with sediment traps, current meters and turbidimeters installed near the bottom and in intermediate waters. Frequent sharp and fast turbidity peaks along with current speed increases were recorded, particularly at 1200m depth in spring and summer. During these events, near-bottom water turbidity increased by up to more than one order of magnitude, current velocity by two to four times and horizontal sediment fluxes by one to three orders of magnitude. When these events occurred, 9-11 days integrated downward particle fluxes collected by the near-bottom sediment trap increased by two to three times. These events were identified as sediment gravity flows triggered by trawling activities along the northern canyon wall. Sediment eroded by the trawling nets at 400-750m depth on this wall seems to be channeled through a gully and transported downslope towards the canyon axis, where the 1200m mooring was located. The sediment gravity flows recorded at the 1200m site were not detected at deeper instrumented sites along the canyon axis, suggesting that they affect local areas of the canyon without traveling long distances downcanyon. These observations indicate that trawling can generate frequent sediment gravity flows and increase sediment fluxes locally in submarine canyons. Furthermore, in addition to the various natural processes currently causing sediment gravity flows and other sediment transport events, human activities such as trawling must be taken into account in modern submarine canyon sediment dynamics studies
2010-08-12T12:14:28Z
2010-08-12T12:14:28Z
2006-02
artículo
Deep Sea Research Part I: Oceanographic Research Papers 53(2): 201-214(2006)
0967-0637
http://hdl.handle.net/10261/27040
10.1016/j.dsr.2005.10.003
eng
https://doi.org/10.1016/j.dsr.2005.10.003
closedAccess
Elsevier