Groundwater-transported dissolved organic nitrogen exports from coastal watersheds

K.D. Kroeger; Marci L. Cole; I. Valiela

doi:10.4319/lo.2006.51.5.2248

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USGS · 70028395

Groundwater-transported dissolved organic nitrogen exports from coastal watersheds

K.D. Kroeger·Marci L. Cole·I. Valiela

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Abstract

We analyzed groundwater-transported nitrogen (N) exports from 41 watershed segments that comprised 10 Cape Cod, Massachusetts watersheds to test the hypotheses that chemical form of N exports is related to land use and to length of flow paths through watersheds. In the absence of human habitation, these glacial outwash-plain watersheds exported largely dissolved organic N (DON) but at relatively low annual rate. Addition of people to watersheds increased rates of both total dissolved N (TDN) and DON export through groundwater. Percent of TDN as DON in groundwater was negatively related to path length of groundwater through aquifers, but %DON was not significantly related to population density on the watersheds. DON was often the dominant form of N exported from the watersheds, even at high population densities. Our results suggest that natural sources are not entirely responsible for organic N exports from watersheds, but, instead, a substantial portion of anthropogenic N introduced to watersheds is exported as DON. This finding is in disagreement with previous results, which suggest that anthropogenic N is exported from watersheds largely as NO 3- and that DON exported from watersheds is from natural sources.

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Limnology and Oceanography Article

Source-reported bounding extent: 41.50446357504803° to 41.96357478222518° latitude; -70.73684692382812° to -70.125732421875° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

K.D. Kroeger, Marci L. Cole, I. Valiela. 2006-09-14. Groundwater-transported dissolved organic nitrogen exports from coastal watersheds. https://doi.org/10.4319/lo.2006.51.5.2248

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