ISSN:
1432-2137
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mathematics
Notes:
Zea mays L.) and soybean [Glycine max (L.) Merr.] yield predictions were within 15 and 20%, respectively, of those measured. Using the macropore option, (constant cracking) greatly improved the prediction of chemical losses to seepage. Annual runoff simulated for corn and soybean under conventional and no-till systems was adequately predicted. The model underpredicted large runoff events and overpredicted runoff events that occurred after long dry periods when soil cracking was a dominant factor. The model overpredicted NO- 3N concentrations in runoff but underpredicted concentrations in near-surface soils. Predicted and measured atrazine [6-chloro-N-ethyl-N′-(1-methylethyl)-1,3,5-triazine-2,4-diamine] and alachlor [2-chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl)acetamide) concentrations in surface runoff compared well, particularly when the computed runoff was close to that measured. In this study, the model was run using the option of constant cracking in the soil. To improve the predictions of agrichemical losses to runoff and seepage, RZWQM should include the capability to predict variable soil cracking based on soil moisture.
Type of Medium:
Electronic Resource
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