1 Interrill Soil Erosion as Affected by Tillage Methods under Cotton in Greece

The effect of reduced tillage, cover crop and planting direction on soil erosion was investigated in sloping cotton field in Larissa, Central Greece. The treatments were three tillage methods: conventional tillage using a plough, reduced tillage using a heavy cultivator, and reduced tillage using a disk harrow, with and without cover crop and tillage and planting of cotton to the contour or to the slope. Winter wheat or vetch was used as cover crops, drilled in autumn. Soil properties measured were dry bulk density, aggregate stability and water infiltration. Rain intensity, runoff and quantities and texture of soil sediment during rainy periods were also measured. The results showed that runoff was affected by all studied parameters. Ploughing significantly increased soil loss but the presence of a winter cover crop significantly reduced these losses in all rain events. Soil losses during winter were three times higher using conventional tillage without cover crop compared to the same tillage system with cover crop. Use of reduced tillage to the contour with cover crop reduced soil loss under 1 t/ha-yr, the accepted soil formation rate. Rain kinetic energy is correlated to soil loss. Soil losses were qualitatively most important in the ploughed plot as the clay content of the sediment was significantly higher than the initial soil