9412113 Boynton This is a project to investigate mechanisms by which production at higher trophic levels in influenced by inputs from adjacent watershed, ocean and atmosphere, using Chesapeake Bay as a study site. The proposed research builds on previous LMER studies (PROTEUS), which focused on how inputs from adjacent systems affect primary projection and recycling processes, to examine the consequences of those processes for fish and other secondary producers in this estuary. The investigators hypothesize that the relatively high rates of secondary production characterizing estuarine ecosystems are attributable, in part, to the pulsing nature of materials and energy inputs and the resulting physical structures and biological patchiness, which act as sites of greatly enhanced activity. The researchers will conduct an ambitious field program which has been designed to examine: 1) how fine-scale distributions (as well as regionally integrated values) of physical and biological properties and processes respond to interannual variations in inputs from terrestrial and oceanic margins; and 2) how physical structures and biological patches influence production and trophic structure of the estuarine ecosystem. A suite of numerical models and comparative analyses will be executed to; (1) integrate field observations; (2) contrast differences between processes measured at coarse and fine scales; and (3) investigate factors regulating trophic structure and secondary production at specific sites. To accomplish these goals the investigators will utilize several new technologies (e.g. rapidly towed CTD, fluorescence, acoustic and optic sensors, aerial remote sensing, real-time in-situ moorings) which have emerged that enable reliable estimates of secondary production and insights into the details of interactions between planktonic assemblages and physical structures. Over the past decade, research attention has focused on the question of how changes in the inputs of nutrients to estuaries creat e regional and interannual variations in primary production, algal biomass, and nutrient recycling. The understanding of these connections in Chesapeake Bay is at a state where researchers can now focus on the next obvious puzzle in estuarine ecology: what makes estuaries so efficient in the transfer form primary to secondary production and how is secondary production related to energy and material inputs from the land, air and ocean.
