MICROPHYTOBENTHIC PRIMARY PRODUCERS IN CALCAREOUS SANDS: PATTERNS IN ABUNDANCE
Calcareous permeable sands account for 40 % of the global continental shelf, yet their role in global biogeochemical cycles is debated. Our ongoing work evaluates and supplements current knowledge on the abundance of sedimentary microphytobenthos (MPB) and their impact on benthic primary productivity and redox cycling. We report methodological improvements in sample processing that enhance extraction of chlorophyll a (Chl a)a) from calcareous sands by 39 %, confirming that these sands host some of the most abundant MPB populations encountered in sedimentary environments, in excess of 1 g m-2 Chl a, or more than 30× those found in estuarine sediments or siliceous sands. Moreover, high abundances are not restricted to the surface layers 1-2 cm below the sediment-water interface, but extend well below this depth and may enhance abundance estimates in calcareous sands by an order of magnitude. We briefly address the physical and ecological processes that may drive these high abundances, e.g., porewater advection, cell filtration, motility, burial, etc.
Hannides, A. K., University of Hawaii, USA, firstname.lastname@example.org
Glazer, B. T., University of Hawaii, USA, email@example.com
Sansone, F. J., University of Hawaii, USA, firstname.lastname@example.org
Time: 16:00 - 18:00
Location: Poster/Exhibit Hall
Presentation is given by student: No