SS3.04 Biogeochemistry of DOC/DON in a Watershed Context
Date: Wednesday, June 12, 2002
Time: 11:45:00 AM
Location: Carson B
 
CanuelEA, Virginia Institute of Marine Science, Gloucester Pt, VA, USA, ecanuel@vims.edu
Pilon, V, L, Virginia Institute of Marine Science, Gloucester Pt, VA, USA, vpilon@vims.edu
Ederington-Hagy, M, , Virginia Institute of Marine Science, Gloucester Pt, VA, USA, mehagy@home.com
Cloern, J, E, US Geological Survey, Menlo Park CA, USA, jecloern@usgs.gov
 
SOURCES OF PARTICULATE ORGANIC MATTER IN THE SACRAMENTO-SAN JOAQUIN RIVER DELTA
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The sources and quality of carbon delivered to San Francisco Bay (SFB) are controlled by production and transformation processes occurring within the Sacramento River-San Joaquin River (SJR) Delta. A goal of this study was to identify the sources of particulate organic matter (POM) in sub-environments along the Delta- Northern SFB continuum using several classes of lipid biomarker compounds and bulk carbon and nitrogen stable isotopes. Principal components analysis revealed unique biomarker signatures for habitats within Northern SFB; marsh sites were distinguished by biomarkers representing higher plants, bacteria and microalgae while the estuarine turbidity maximum was dominated by biomarkers representing heterotrophic processes. Unique signatures were also observed for each of the rivers draining into the Delta with a stronger diatom, "fresh" algal signature evident for the SJR. In a comparison of three shallow lake sites, differences in the dominance of plant, bacterial and microalgal sources were documented. While bulk stable isotope analyses complemented biomarker analyses, their combined use provides a more powerful means for distinguishing sources in complex ecosystems.