9317968 Correll This study explores the effects of geology, land use distribution, and weather on discharges of water, sediment, nitrogen, phosphorus, and silicate from watersheds throughout the Chesapeake Bay. Past measurements of discharges from 29 watersheds in the Coastal Plain and Piedmont provinces have revealed dramatic differences relating to both geology and land use. The proposed work will expand the study to include watersheds in the Ridge and Valley and Appalachian Plateau regions of the Chesapeake watershed, and will increase the numbers and types of watersheds compared. %%% Relating landscape structure to nutrient discharges is a primary objective. Computerized geographic information systems are used to quantify geographic patterns, identify indices of landscape structure that relate to nutrient discharge, and develop models to predict discharges. These efforts will be expanded to cover a broader geographical scale. Results from data at different levels of spatial resolution will be compared to explore how knowledge from small-scale, fine-grain studies extrapolates to large-scale. coarse-grain analyses. %%% These watershed studies and geographic analyses will provide basic knowledge on landscape function and the factors controlling nutrient fluxes. The study will develop methods for linking nutrient discharge measurements, GIS, and landscape models to extrapolate predictions of nutrient flux to regional scales. This will provide essential knowledge for predicting nutrient discharges to Chesapeake Bay.
