Abstract
Cold-water coral reefs and mounds are observed mainly on slopes and topographic highs, in areas with high current speeds. Previous investigations of the near-bed hydrodynamic regime around cold-water coral mounds at the Southwest Rockall Trough margin have revealed the presence of internal waves with a diurnal tidal frequency. Hitherto only short-term measurements existed on the particle supply to the corals and data are lacking on the seasonal variability. Bottom landers equipped with sensors recording near-bottom current dynamics were deployed at two sites in a mound area on the Southwest Rockall Trough margin, one with a dense coral cover and one without coral cover. At both sites a similar seasonal variation in internal-wave activity was recorded with high activity during winter and summer months and less dynamic conditions in spring and autumn. Increased intensity of internal-wave activity, reflected in higher average near-bottom current speed and amplitude of daily temperature fluctuations, results in higher mass fluxes as recorded in the sediment traps. On the site without coral cover, mass fluxes are two times higher, compared to the site with dense coral cover. During periods of high mass fluxes a predominance of resuspended material was observed at both sites, as indicated by reduced
Original language | English |
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Pages (from-to) | 1026-1040 |
Number of pages | 15 |
Journal | Deep-Sea Research Part 1. Oceanographic Research Papers |
Volume | 56 |
DOIs | |
Publication status | Published - 2009 |