Tillage Effects on Characteristics of Soil Water under Winter-wheat in North China

摘要

Tillage performs an important task in preparing a good seedbed for crop growth.Conventional tillage usually leads to more soil evaporation, which results in inadequate soil water contents. Minimum tillage could reduce soil evaporation and enhance soil moisture. In this paper, attempts are made to determine the effects of different tillage practices on soil moisture characteristics and physical properties under winter-wheat in Luancheng Ecological Station, China. For winter-wheat, tillage treatments comprised conventional tillage (CT),rotary tillage (RT), and minimum tillage (MT). Summer-corn was planted before winterwheat harvest with no tillage. Soil cores of plough layer were collected for measuring soil bulk density, soil water retention curve. Soil water retention curve was simulated with the model of Van Genuchten. Soil water content of plough layer was measured by TDR. Soil bulk density was 10% higher in MTr (ridge of MT) than that of in MTf (furrow of MT). Bulk density increased with increasing depth and time. Using a simulation equation for soil water retention, the water holding capacity was calculated. Within the range 2.5- 4.2 of the pF, the soil moisture of MTr was the highest. At the pF value of 2.5, the soil moisture of 0.05 m soil was 0.32, 0.29, 0.31, 0.26 m3 m-3 for MTr,MTf,RT and CT, respectively. The water holding capacity of MT was 11.23%, 4.18% and 24.78% greater than MTf , RT and CT, respectively. At the pF value of 4.2, the soil moisture at 0-5 cm layer of MT was 0.20, which was 15.63%, 11.42% and 35.52% higher than that of MTf, RT and CT. Soil moisture of the plough layer was recorded by TDR, and that of MT was the highest and CT the lowest in the winter-wheat growth period.