SS3.15 Physical Forcing and Pelagic-Benthic Interactions in Aquatic Systems
Date: Thursday, June 13, 2002
Time: 3:00:00 PM
Location: Oak Bay
 
MayerLM, University of Maine, Walpole, USA, Lmayer@maine.edu
Laursen, A, , University of Maine, Orono, USA, 
Townsend, D, , University of Maine, Orono, USA, 
Pettigrew, N, , University of Maine, Orono, USA, 
Wong, M, , University of Maine, Orono, USA, 
Loder, T, , University of New Hampshire, Durham, USA, 
Schoudel, D, , University of New Hampshire, Durham, USA, 
 
RIVER INPUT, STRATIFICATION, NUTRIENTS AND NUTRITIONAL SESTON IN THREE MAINE ESTUARIES
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Three adjacent estuaries - the Damariscotta, Sheepscot, and Kennebec - are alike in most respects except for ascending, order-of-magnitude increases in river input. Their hydrography, nutrient, planktonic, and particle dynamics were examined over a year. These systems ranged from stratified to well-mixed over the year. Although river input was the most important factor controlling stratification, estuarine morphology also appears important. Nutrient inputs ranged from dominantly riverine in the Kennebec to marine in the Damariscotta. The Damariscotta acts as a simple conversion chamber in which dissolved nutrients from the ocean are converted to particulates, which are largely exported back to the ocean, after feeding abundant filter-feeder populations. Labile particulate organic matter was often a major source of N from the Kennebec River. The Sheepscot appeared least able to convert nutrient inputs into biological production, perhaps due an unfavorable light regime. Planktonic production was dominated by diatoms, and provided the bulk of nutritionally useful particles for heterotrophic organisms. Buildup of detrital organic material, especially in summer, provided a pool of less easy-to-digest organic matter in the water column.