Ecosystems worldwide are undergoing changes of unprecedented magnitude and speed as a result of human influence. Simultaneous climate warming, eutrophication, overfishing, and exotic invasions create an urgent need to understand how stressors interact. Of the many such facets of global change, the most irreversible is extinction of biodiversity. Thus, understanding how changing biodiversity mediates ecosystem processes is central to both basic ecology and to practical prediction of global change impacts on ecosystems and the services they provide to humanity. In particular, effects of changing community composition are often mediated through trophic interactions, making the integration of food web ecology into BDEF research an important frontier in understanding the dynamics of complex natural ecosystems. Crossing this frontier will require integration of long-term time series data on multitrophic communities, experimental analyses of community interactions, and new dynamic modeling approaches.
This research builds on a decade of research in a Chesapeake Bay eelgrass (Zostera marina) ecosystem to address this goal. The proposed research brings together an experimental ecologist and a biomathematician, employing a complementary suite of experiments, analyses of continuing longterm monitoring data across three trophic levels (eight years of monthly sampling to date), and simulation modeling, to construct and parameterize a dynamic food web model of a Chesapeake Bay eelgrass community. This research will establish the Chesapeake seagrass food web as one of a small number of ecological systems in which the requisite field data and experimental characterization of interaction strengths are available for such dynamic modeling, facilitating its use as a model system for exploring problems in both general and applied ecology.
Broader impacts of this research include: (1) field research experiences for a large number of students at several levels, as well as K-12 teachers, (2) complementary integration with long-running monitoring programs for water quality, submerged vegetation, and fish assemblages, and (3) valuable long-term baseline data with which to evaluate and forecast effects on economically important estuarine ecosystems of climate warming, changes in fishing pressure, eutrophication, and other stressors.
