Science Serving Maryland's Coasts

Nicole Carlozo, St. Mary's College of Maryland

Class Year: 

Project Title: 

Water Chemistry Fluctuations in Response to Human Population and Land use in the Delaware River, Hudson River, and Chesapeake Basins


Anthropogenic activities, including deforestation, waste water output, agricultural land use, developed land use, and atmospheric deposition, all contribute towards river nitrogen and phosphorus concentrations. Water quality data from USGS for 8 subbasins within the Hudson River basin, the Delaware River basin, and the Chesapeake basin was analyzed with 2000 population data from the US Bureau of the Census and 2001 land cover data from the National Land Cover Database. Population density, percent developed land, and percent agriculture varied concentrations of N and P in rivers, reducing water quality within the basins. Forests, agriculture, and developed lands were the most prominent land uses within all basins. Long term regressions show minor improvement in water quality during 1970-2005, despite attempts to reduce anthropogenic impacts. Short-term regressions show similar improvement from 1995-2005. The 1995-2005 time-frame was wetter than the long-term mean at every basin site, and water yield increased as site latitude increased due to mean temperature and evapotranspiration. Human presence on land still has large negative effects on water quality.