Nitrogen loading in coastal watersheds of New Hampshire: An application of the SPARROW model

Abstract

In coastal New Hampshire as well as throughout the world there has been an increase in Nitrogen (N) loading to coastal areas. N is considered the limiting nutrient in coastal waters and can lead to eutrophication. Understanding the sources of coastal inputs is difficult because of the many possible sources of N are found in the watershed and few are adequately sampled. Modeling is an important tool in understanding the sources of N in a watershed. In this research, the New England SPARROW (Spatially Referenced Regression on Watershed Attributes) will be applied to predict nitrogen loading in the Exeter, Oyster, Lamprey, Cocheco and Salmon Falls watersheds in coastal New Hampshire. By applying the same regression techniques for all of New England to data collected from the NH Coastal region a more accurate model was developed. The NH Coastal model predicts more accurately and better defines the source variables in the region