| Autor: |
Terry, R. V., Powers, W. L., Olson, R. V., Murphy, L. S., Rubison, R. M. |
| Zdroj: |
Journal of Environmental Quality; January 1981, Vol. 10 Issue: 1 p22-26, 5p |
| Abstrakt: |
A field experiment was performed to determine effects various application rates of beef feedlot runoff had on the NO3‐N concentration of a shallow aquifer. A randomized complete block design with 3 blocks and 5 application rates (0.0, 2.5, 5.1, 7.6, 10.2 cm) was used each irrigation. Treatments were applied after precipitation had produced sufficient runoff. A dual well system (shallow and deep wells in each plot) was sampled every month for 3 years and the collected water was analyzed for NO3‐N. Graphical and statistical examinations of the data indicated shallow well NO3‐N concentrations in block 3 were high (up to 46 mg/liter) and extremely variable. Statistical analyses performed on means from 12 quarters showed only one significant treatment effect in the seventh quarter. However, during most quarters the highest application rate showed the lowest concentration of NO3‐N in the ground water. The dual well system revealed parallel fluctuations in shallow and deep wells, indicating that some changes in NO3‐N resulted from a regional phenomenon rather than from applied treatments. |
| Databáze: |
Supplemental Index |
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