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Nitrogen Loading from Selected Long Island Sound Tributaries from 1995 to 2016

January 20, 2022

This dashboard application displays information from the following U.S. Geological Survey data release:

Mullaney, J.R., 2020, Nitrogen concentrations and loads and seasonal nitrogen loads in selected Long Island Sound tributaries, water years 1995-2016: U.S. Geological Survey data release,

This U.S. Geological Survey application displays data on nitrogen concentrations and loads (fluxes) for multiple nitrogen species and river discharge data collected from October 1994 to September 2016 (water years 1995 to 2016). Data on flow and nitrogen concentrations were analyzed using the USGS EGRET R package (Hirsch and DeCicco, 2015) and the method of WRTDS (Weighted Regression on Time Discharge and Season) by Hirsch and others (2010). Output data were used in an analysis of nitrogen budgets of the Long Island Sound estuary (Vlahos and others, 2020).

Data and outputs are summarized for water-quality data collected at 18 water-quality monitoring stations in the Long Island Sound watershed. Specific data displayed in this application include calculated annual nitrogen concentrations and loads by water year, calculated annual flow-normalized nitrogen concentrations and loads by water year (for sites with 20 or more years of data), and calculated annual seasonal loads of each nitrogen constituent by calendar year. The water year used by the U.S. Geological Survey runs from October 1 through September 30 and is designated by the year in which it ends.

Daily mean river discharge data and sampled nitrogen concentration data for each water-quality monitoring site are available as files accessible with R statistical software from the original data release at: