Trends and seasonal patterns of nitrogen and phosphorus concentrations and loads in two Mississippi Alluvial Plain watersheds following nutrient reduction efforts

As part of the Clean Water Act, Section 319 authorizes funding that is distributed to Mississippi Department of Environmental Protection Agency to address nonpoint sources of pollution in the state of Mississippi. For this project, Weighted Regressions on Time, Discharge, and Season (WRTDS) models (Hirsch and others, 2010) were used to perform a trend analysis on nitrogen and phosphorus concentrations and fluxes. The analysis was performed on both annual and daily timescales at 6 locations in Mississippi: (1) Harris Bayou, (2) Overcup Slough Tributary 2, (3) Porter Bayou -- Shaw, (4) Porter Bayou -- Stephensville, (5) Porter Bayou Tributary, and (6) Richies Bayou. This data release includes 24 comma-separated value (csv) files containing data used in the analysis. The csv files are organized into 6 .zip files, one for each study site. Within each .zip file, there are 4 csv files with data for: (1) annual nitrogen (site name_annual_nitrogen.csv), (2) daily nitrogen (site name_daily_nitrogen.csv), (3) annual phosphorus (site name_annual_phosphorus.csv), and (4) daily phosphorus (site name_daily_phosphorus.csv).