SS3.19 Role of Benthic Communities in the Cycling and Balance of Nitrogen in Bays and Estuaries
Date: Friday, June 14, 2002
Time: 10:45:00 AM
Location: Oak Bay
 
ChanF, Oregon State University, Corvallis, USA, chanft@bcc.orst.edu
Menge, B, A, Oregon State University, Corvallis, USA, mengeb@bcc.orst.edu
Nielsen, K, , Oregon State University, Corvallis, USA, nielsenk@bcc.orst.edu
Phillips, N, , University of California, Santa Barbara, Santa Barbara, USA, n_philli@lifesci.ucsb.edu
Daley, B, A, Cornell University, Ithaca, USA, bad11@cornell.edu
Hudson, G, , Oregon State University, Corvallis, USA, hudsong@bcc.orst.edu
 
EXCEPTIONAL PHYTOPLANKTON BIOMASS AND NUTRIENT USE EFFICIENCY IN THE NEARSHORE WATERS OF THE CALIFORNIA CURRENT SYSTEM?
image
In contrast to our understanding of mesoscale physical and biological processes in the shelf waters of the California Current System (CCS), the extent to which coastal upwelling mediates the productivity of shallow waters at the land-sea margin has remained poorly characterized. As part of a research program examining nearshore benthic-pelagic coupling in the CCS, we carried out extensive shore-based assessments of seasonal and spatial variations in nutrient and chlorophyll availability along the Oregon coast. While upwelling enhancements of nutrient supply and primary productivity is well recognized for the CCS, nearshore waters appear to represent an upper end-member system in marine productivity. Summertime chlorophyll concentrations upwards of 150 ug/l were repeatedly measured. We investigated the possible roles of riverine nutrient inputs and physical aggregation in elevating near-shore phytoplankton and seston abundance. Temperature, salinity, inorganic nutrient data, and mass balances of nitrogen pools do not point to enhancement of near-shore phytoplankton biomass by either process. Comparisons of chlorophyll and total nitrogen across other pelagic systems suggest instead that elevated phytoplankton biomass reflect exceptional nutrient use efficiency in in-situ nearshore production.