CORP Author |
Illinois State Water Survey Div., Champaign.; Illinois Univ. at Urbana-Champaign.; Department of Agriculture, Washington, DC.; Department of the Interior, Washington, DC.; Environmental Protection Agency, Washington, DC. |
Abstract |
This report presents data summaries from two networks. Contour maps present NTN data. Concentration and deposition maps present MDN data. The line graphs presenting AIRMoN concentrations over time are not available in this report. The NTN maps portray spatial variability in the concentration and deposition of selected acids, nutrients, and base cations on regional and national scales. Only sites that meet prescribed data completeness criteria are included. In 1997, 165 sites met these criteria. Annual concentration or deposition values are printed next to each site. The concentrations are volume-weighted averages. The MDN maps show the concentration and deposition of total mercury in precipitation. Only sites meeting prescribed data completeness criteria are included. In 1997, 21 sites met these criteria. Annual concentration or deposition is printed next to each site. The concentrations are volume-weighted averages. |