| Abstrakt: |
Soil loss reductions by residue cover (mulch) under field conditions were verified by deriving a mulch factor for no‐till, chisel plowing plus disking, and spring sweep tillage using anchored and unanchord corn (Zea maysL.) and soybean [Glycine max(L.) Merr.] residues on a 4.5% slope 10.5 m long on Russell silt loam soil. A mulch factor was also derived for sweep tillage using anchored wheat residue on a 6.5% slope Martinsville loam soil, for simulated slope lengths of 35, 60, 85, 110, and 135 m. Both soils are Typic Hapludalfs. The studies were conducted using simulated rainfall and field plots. A crop residue mulch was relatively more effective than roughness alone in reducing soil loss on smoother soil surfaces and on the longer slopes. Corn residue was more effective in reducing erosion than soybean residue, and residues partially incorporated into the soil were more effective in reducing soil loss than residues loose on the surface. The findings showed that the b‐value in the mulch factor (Fm)‐% residue cover (M) equation Fm= e‐bMvaried appreciably depending on roughness, and type and incorporation of the residue. |
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