Mary Freeman
Friday, October 17, 2008 - 11:00-11:30
Streamflow regimes, described by flow volume and timing, are primary drivers of many ecological processes in streams and rivers. Alteration of flow regimes, e.g., by water diversions, impoundments, flow regulation, and changes in land use and land cover, can affect population processes that influence species persistence and thus the ability of a system to support native biodiversity. We are developing a landscape-scale modeling framework for predicting how specific changes in streamflow regimes are likely to influence aquatic communities in the upper Flint River basin, GA. The upper Flint River drains about 6800 km2 and contains substantial river shoals habitat that supports a variety of native fishes (including five endemic species), mussels (including three federally listed species) and aquatic plants. Urban growth in the headwaters, which encompass a portion of the Atlanta Metropolitan Area, and increasing demands for offstream water-use will affect future flow regimes in the upper Flint. Our modeling approach integrates flow dynamics with basin geomorphology and land use change, to provide a basis for predicting changes in fish assemblages across the basin under alternative future scenarios. We intend this as an adaptive framework, within which model components will be iteratively improved with better understanding of mechanisms linking land use, hydrology, and aquatic biota, to provide useful guidance to natural resource managers.
Keywords: AQUATIC BIODIVERSITY, WATER AVAILABILITY, PREDICTIVE MODELS