15 Earth Biogeochemistry (Posters)

Thursday, 31 March 2016
8:00 AM - 5:30 PM
Exhibit Hall

ELEMENTAL STOICHIOMETRY, AND NUTRIENT AND MINERAL FLUXES IN THE SANTA BARBARA BASIN OVER THE PAST TWO DECADES

Paper number: 15-8
Program: Theme Sessions
Time: 8:00 AM – 5:30 PM

Authors

Abstract

Nutrient composition plays an important role in plankton speciation and therefore marine biological production. In regions dominated by upwelling, the composition and magnitude of nutrients upwelled into surface waters not only influences surface food web dynamics, but also the composition and magnitude of particles that reach deep waters, are remineralized, and even sequestered in deep sediments. The Santa Barbara Basin off the coast of Southern California is an area that encounters seasonal upwelling due to strong northwesterly winds that occur along the west coast of the United States. Several studies suggest that plankton community structure has undergone a large scale shift in the year 2000 due to changes in upwelling intensity or upwelling water concentrations. To determine long term and annual shifts in particulate mineral and nutrient fluxes in this location, total mass, particulate carbon, nitrogen, and phosphorus, as well as carbonate and opal were measured in sediment trap continuously deployed at 500 m since 1993. Fluxes will be analyzed with respect to season, long term trends, and elemental stoichiometry. Preliminary results suggest significant increases in opal and particulate nutrient fluxes over the past decade, coincident with large scale increases in harmful algal blooms in Santa Barbara Basin surface waters.

Geological Society of America Abstracts with Programs. Vol. 48, No. 3

doi: 10.1130/abs/2016SE-273542

© Copyright 2016 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.