EFFECTS OF TILLAGE AND CROP-ROTATION ON PHYSICAL-PROPERTIES OF A LOAM SOIL

Advances in the development of non-residual herbicides have increased the interest in minimum tillage systems as an alternative to conventional cultivation. This study compared the effects of conventional tillage (CT), minimum tillage (MT) and zero-till (ZT) with continuous winter wheat, winter wheat-summerfallow, and winter wheat-barley-summerfallow on various properties of a Brown Chemozemic loam. Saturated hydraulic conductivity (HC), soil moisture retention, bulk density (BD) and infiltration rate of the soil were measured. The effects of crop rotation by tillage or crop rotation on these soil physical properties were not significant after 8 years of tillage. In general, the BD of the soil under ZT was greater than that under CT in the tillage zone and was lower below the tillage zone. The HC of ZT soil was less than that of CT soil in the tillage zone and greater below the tillage zone. Infiltration rates were not different among the tillage treatments. Although significant differences in some soil properties occurred among tillage treatments, these differences were likely to be too small to affect crop production.