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Thesis (M.S.)—University of Nebraska—Lincoln, 1969. Department of Department of Agronomy.


Copyright, the author. Used by permission.


Many of the fine textured, deep loess-derived soils of eastern Nebraska may have considerable accumulations of residual nitrate nitrogen after several years of legumes or heavy fertilization.

Most soil tests for nitrogen do not accurately evaluate the subsurface accumulation of Nitrogen (N), and the resulting uncertainty in fertilizer recommendations may contribute to the problem of nitrate accumulation. The economic consequences in terms of fertilizer costs are obvious.In addition, the leaching of nitrates into the groundwater and well water may be a future hazard to man and animals.

The purpose of this study was (1) to measure the recovery of N from specific depths as great as 6 feet; and (2) to determine what influence residual soil nitrogen levels have on the recovery of the isotope from these depths.

Advisor(s): Gary A. Peterson, R. A. Olson