Skip to main content
U.S. flag

An official website of the United States government

Nitrogen budgets of the Long Island Sound estuary

November 22, 2019

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 × 106 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/(m2year). 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.

Publication Year 2020
Title Nitrogen budgets of the Long Island Sound estuary
DOI 10.1016/j.ecss.2019.106493
Authors Penny Vlahos, Michael Whitney, Christina Menniti, John R. Mullaney, Jonathan Morrison, Yan Jia
Publication Type Article
Publication Subtype Journal Article
Series Title Estuarine, Coastal and Shelf Science
Index ID 70217731
Record Source USGS Publications Warehouse
USGS Organization New England Water Science Center