Lumped Parameter Models for Predicting Nitrogen Transport in Lower Coastal Plain Watersheds
hl recent years physically based comprehensive disfributed watershed scale hydrologic/water quality models have been developed and applied 10 evaluate cumulative effects of land arld water management practices on receiving waters, Although fhesc complex physically based models are capable of simulating the impacts ofthese changes in large watersheds, they are often prohibitive for regular applications because of excessive input data requirements and because of uncertainties in both the model proccsscs and input data. This task is beyond practical reality for policy makers and managers who need 10 make decisions about multiple watersheds with limircd rime and resources. Nevertheless important decisions need to be made with regard to nutrient and water managetnent practices at the field and watershed scales. Models are needed to make decisions that reflect our current understanding of the system yet require input parameters that can b$ readily determined with a minimum of uncertainty.