Many Toxics Program investigations include or focus directly on the occurrence, transport and ecological effects of nutrients in the environment. The major nutrients nitrogen and phosphorus typically are studied; however, this research includes any process or chemicals that enrich or otherwise affect nutrient budgets in natural as well as anthropogenically affected water resources. Nutrients from agricultural, urban, and other sources are included in these investigations. The information presented on this page cuts across lines drawn by individual investigations and projects so that information on the fate and effects of nutrients can be presented in one place.
Investigations and Research Activities
USGS scientist lowering a water-quality sampler into the Iowa River near Marengo, IA, (site ID 05453100). during the 1993 flood of the upper Mississippi River Watershed. The samples were analyzed for nutrients and pesticides.
Average annual nitrate concentrations in selected rivers during 1905-07 and 1980-96 (FS 135-00).
Science Feature Articles
- Decadal surface water quality trends under variable climate, land use, and hydrogeochemical setting in Iowa, USA: Green, C.T., Bekins, B.A., Kalkhoff, S.J., Hirsch, R.M., Liao, L., and Barnes, K.K., Water Resources Research, v. 50, no. 3, p. 2425-2443, doi:10.1002/2013WR014829 (IN PRESS).
- Challenges for mapping cyanotoxin patterns from remote sensing of cyanobacteria: Stumpf, R.P., Davis, T.W., Wynne, T.T., Graham, J.L., Loftin, K.A., Johengen, T.H., Gossiaux, D., Palladino, D., and Burtner, A., Harmful Algae (IN PRESS).
- EPA, NASA, NOAA, and USGS collaborate to develop a Cyanobacteria Assessment Network (CyAN): Schaeffer, B.A., Loftin, K.A., Stumpf, R.P., and Werdell, P.J., EOS, Transactions of the American Geophysical Union (IN PRESS).
- Dairy-impacted wastewater is a source of iodinated disinfection byproducts in the environment: Hladik, M.L., Hubbard, L.E., Kolpin, D.W., and Focazio, M.J., 2016, Environmental Science and Technology Letters, doi:10.1021/acs.estlett.6b00109 (Advanced Web release).
- Spatial and temporal variation in microcystins occurrence in wadeable streams in the southeastern USA: Loftin, K.A., Clark, J.M., Journey, C.A., Kolpin, D.W., Van Metre, P.C., and Bradley, P.M., 2016, Environmental Toxicology and Chemistry, v. 35, doi:10.1002/etc.3391 (Advanced Web release).
- Predicting characteristics of rainfall driven estrogen runoff and transport from swine AFO spray fields: Lee, B., Kullman, S.W., Yost, E.E., Meyer, M.T., Worley-Davis, L., Williams, C.M., and Reckhow, K.H., 2015, Science of the Total Environment, v. 532, p. 571-580, doi:10.1016/j.scitotenv.2015.06.051.