GALLERY OF MAPS

• Patterns of risk of nitrate contamination of groundwater. (95 K GIF)

• NAWQA study units where nitrate concentrations in ground water were significantly higher beneath agricultural areas than beneath undeveloped areas. (10K GIF)

• NAWQA study units where nitrate concentrations in surface water were significantly higher downstream from agricultural areas than from undeveloped areas. (10K GIF)

• Centers of urban population, 1990. (24 K GIF)

• Population change by county in the coterminous United States from 1970 to 1990. (21 K GIF)

• Estimated nonpoint-source inputs of nitrogen applied in commercial fertilizer, 1987. (14K GIF)

• Estimated nonpoint-source inputs of phosphorus applied in commercial fertilizer, 1987. (14K GIF)

• Estimated nonpoint-source inputs of nitrogen in animal manure, 1987. (15K GIF)

• Estimated nonpoint-source inputs of phosphorus in animal manure, 1987. (15 GIF)

• Estimated atmospheric deposition of nitrogen in the United States. (10K GIF)

U.S. Department of the Interior, U.S. Geological Survey Maintainer: Kerie Hitt (kjhitt@usgs.gov) Last update: 17:47:41 Mon 09 Jul 2001 Privacy Statement || Disclaimer || Accessibility URL: http://water.usgs.gov/nawqa/nutrients/maps.html