| Autor: |
R. F. Spalding, M. E. Exner |
| Rok vydání: |
1991 |
| Předmět: |
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| Zdroj: |
Nitrate Contamination ISBN: 9783642760426 |
| DOI: |
10.1007/978-3-642-76040-2_2 |
| Popis: |
Nitrate is a highly mobile ion applied as fertilizer or derived by microbiologically induced oxidation of numerous nitrogen-containing chemicals. Because of the ubiquitous nature of nitrate sources, no American state is completely immune to nitrate contamination. Yet, nationally there is a skew distribution of nitrate-contaminated ground- and surface-water areas. The hydrogeology of a generic nitrate-vulnerable ground-water system is a sand and gravel or fractured-rock aquifer overlain by an unsaturated zone devoid of retarding layers. The overfertilization and overwatering that are associated with irrigated row-cropping increase the probability of developing problem areas in these regions. Streams receiving large amounts of runoff or lateral influent seepage in highly agricultural regions are vulnerable to nitrate contamination. To a large extent nitrate problems in the eastern Corn Belt are focused on surface waters. In the humid southeast the persistence of nitrate in the subsurface may not be long enough to create nonpoint problem areas. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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