The effects of no-tillage practice on soil physical properties
No-tillage (NT) is now widely recognized as a variable concept for practicing sustainable agriculture. The objectives of this study were to summarize the effects of no-tillage on soil physical properties and outline the environment capability of no-tillage practice. The effect of no-tillage on soil bulk density was a debated question, and in order to make it comparable, the study conditions (soil texture, climate conditions, planting system, straw covering conditions on soil surface, soil water content and the notillage practiced period) were first addressed. Total porosity, a measure of the porous space left in the soil for air and water movement, was inversely related to bulk density. When the conventional tillage practices were used, the volume of soil macropores (>0.05 cm) was higher than that under no-tillage practice. With time, it decreased greatly, but the conventional tillage treatment still kept the lead. As a result of soil agitation, the soil aggregate rate under conventional tillage cropland was generally lower than that under the no-tillage practiced cropland. The studies of no-tillage on soil temperature and on crop yield also have conflicting results because of the absence of systemically long term monitoring, and there was little information on the effects of no-tillage on crop quality. Therefore, future perspectives of no-tillage research were put forward.
Key words: No-tillage, conventional tillage, soil physical property, yield.