Nitrogen budgets of the Long Island Sound estuary

Penny Vlahos; Michael Whitney; Christina Menniti; John R. Mullaney; Jonathan Morrison; Yan Jia

doi:10.1016/j.ecss.2019.106493

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Nitrogen budgets of the Long Island Sound estuary

Penny Vlahos·Michael Whitney·Christina Menniti·John R. Mullaney·Jonathan Morrison·Yan Jia

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Abstract

Nitrogen (N) inputs to coastal ecosystems have significant impacts on coastal community structure. In N limited systems, increases in N inputs may lead to excess productivity and hypoxia. Like many temperate estuaries, Long Island Sound (LIS), a major eastern U.S. estuary, is a N limited system which has experienced seasonal hypoxia since the 1800s. This study is the first effort to constrain the total N cycle in this estuary. The approach utilizes data collected over the last two decades in the LIS time series with hydrodynamic model results to generate both monthly and annual N budgets between 1995 and 2016. Of the total N that is delivered to LIS through rivers and atmospheric inputs, 40% is exported to the adjacent continental shelf on the order of 10.8 ± 8.9 × 10 6 kg N/year. Of this export, 41% is dissolved organic N, 29% is particulate organic N, 32% is nitrate + nitrite, and −3% is ammonium. The remaining 60% of the N delivered to LIS is either buried in sediments or lost through denitrification. This inferred internal loss rate is equivalent to 5.4 g N/(m 2 year). This study serves as an example of the significant inter-annual variations that estuarine budgets undergo as efforts to understand coastal biogeochemical cycles move forward.

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Estuarine, Coastal and Shelf Science Article

Source-reported bounding extent: 40.77638178482896° to 41.413895564677304° latitude; -73.8720703125° to -71.4605712890625° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

Penny Vlahos, Michael Whitney, Christina Menniti, John R. Mullaney, Jonathan Morrison, Yan Jia. 2020. Nitrogen budgets of the Long Island Sound estuary. https://doi.org/10.1016/j.ecss.2019.106493

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