Duplin River seston variability Dr. Merryl Alber University of Georgia

Dept. of Marine Sciences University of Georgia Athens Georgia 30602-3636 USA

malber@uga.edu https://marsci.uga.edu/directory/people/merryl-alber https://orcid.org/0000-0002-9467-4449 Georgia Coastal Ecosystems LTER Project

Dept. of Marine Sciences University of Georgia Athens Georgia 30602-3636 USA

gcelter@uga.edu https://gce-lter.marsci.uga.edu/ Dr. Merryl Alber University of Georgia

Dept. of Marine Sciences University of Georgia Athens Georgia 30602-3636 USA

malber@uga.edu https://marsci.uga.edu/directory/people/merryl-alber https://orcid.org/0000-0002-9467-4449 Principal investigator 1994-01-01 2004-12-31 Dr. Merrilee Thoresen University of Georgia

Graduate research assistant 1994-01-01 2004-12-31 2026

M. Thoresen (Ph.D. student, UGA) and M. Alber (UGA) conducted an experiment to examine the quantity and quality of seston in the Duplin River, Georgia, and how it varied over different temporal and spatial scales. Average suspended particulate material (SPM), particulate organic carbon (POC), and chlorophyll a concentrations were significantly higher at the mouth (327.6 mg L-1, 5.0 mg L-1, 19.9 µg L-1) than at the headwaters (93.4 mg L-1, 1.6 mg L-1, 9.4 mg L-1). The quality of the seston was lower at the mouth with significantly higher carbon to nitrogen and POC to chlorophyll a ratios, but the seston was detrital-dominated throughout the inlet. Significant differences in seston characteristics were observed over tidal cycles at the mouth only, but all sites exhibited differences over lunar (spring tides greater than neap) and seasonal (spring and summer maxima) cycles. These differences were most consistent for SPM but were observed at some stations for other characteristics as well. Seston variability was greatest at the mouth at any temporal scale, but when compared within each site, the two sites closest to the mouth exhibited variability on tidal and lunar scales that was comparable to or even greater than seasonal scales, whereas at the up-river sites seasonal variability was the greatest.

Question 2: How do the spatial and temporal patterns of biogeochemical processes, primary production, community dynamics, decomposition, and disturbance vary across the estuarine landscape, and how do they relate to environmental gradients? (more information)

LTER NSF Duplin River Georgia GCE chlorophyll particulate organic carbon seston suspended particulate material Overall geographic extent of the research project -81.301987 -81.263124 31.486493 31.410854 1994-01-01 2004-12-31

National Science Foundation grant number OCE-99821339 and NOAA NERRS graduate student fellowship

estuary marsh complex Duplin River - Duplin River transect used for GCE quarterly hydrographic monitoring surveys. Nominal profiling stations are defined at various locations along the Duplin River west of Sapelo Island, Georgia. -81.301987 -81.263124 31.486493 31.410854 Thoresen, M. 2004. Temporal and spatial variation in seston available to oysters and the contribution of benthic diatoms to their diet in the Duplin River, Georgia. Ph.D. Dissertation, University of Georgia, Athens, Georgia. 220 pp. http://gce-lter.marsci.uga.edu/public/files/pubs/Thoresen_Merrilee_PhD_2004.pdf Thoresen, M. and Alber, M. 2003. Presentation: POC concentrations over different scales of variability in a tidal inlet (Duplin River, Georgia). Southeastern Estuarine Research Society meeting. March 2003, Atlantic Beach, NC. Thoresen, M. and Alber, M. 2003. Poster: Temporal and spatial dynamics of seston in the Duplin River: Implications for oyster food resources. LTER All-Scientists Meeting. September 2003, Seattle, WA. Thoresen, M. and Alber, M. 2000. Presentation: Tidal dynamics of particulate material in the Duplin River (Sapelo Island National Estuarine Research Reserve): An evaluation of the YSI 6025 chlorophyll probe. The National Estuarine Research Reserve Annual Workshop. National Estuarine Research Reserve, Oct 01, 2000, Williamsburg, Virginia.