A Study of Factors Influencing the Nitrogen and Phosphorus Contents of Nebraska Waters
1973
Muir, John | Seim, Edwin C. | Olson, R. A.
The purpose of this investigation was to determine magnitude and sources of nutrient N and P in Nebraska waters. Correlation studies reveal little relation between N and P concentrations of the water and agricultural use of fertilizers. Nutrient levels in the water are governed more by human and livestock densities and intensity of irrigation development than by agronomic production factors. Only at sites of intensive irrigation development on very sandy soils and with irrigation of valley positions of shallow water table has fertilizer N contributed substantially to a reduction in ground-water quality. Nutrient concentrations in streams fluctuate widely with (i) varied time and rate of organic waste intrusions and subsequent biological assimilation and (ii) major runoff events. Reservoirs on streams also have a major modifying action in reducing sediment and fertility load. The observed higher N content of streams during periods of peak flow can be attributed partially to the high N content of precipitation and its direct runoff into streams during periods of high rainfall intensity.
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