耕作方式对土壤水动态变化及夏玉米产量的影响

    Effects of Tillage Practices on the Variation of Soil Moisture and the Yield of Summer Maize

    • 摘要: 一个连续2年的田间耕作试验在夏玉米生长期内完成,分析对比3种不同耕作方式对土壤水动态变化过程及对作物产量的影响。耕作扰动对土壤水动态变化的影响是明显的,夏玉米生长初期免耕下的表层土壤持有较高的水分,这归因于土壤非耕扰动、冬小麦残茬覆盖以及耕层土壤孔隙尺度分布的变化;另一方面,深松土壤受到耕作活动的强烈干扰,苗期耕层土壤蓄水明显小于传统耕作。耕作方式对土壤水差异的影响伴随着作物的生长发育过程显著减弱。深松耕作对作物根系生长发育状况及作物增产效果的作用是十分显见的。

       

      Abstract: Field experiments from 1996 to 1997 growing seasons were conducted to determine the effects of conventional tillage (CT), no tillage (NT) and subsoiling tillage (ST) practices on the soil water situation and the crop yield. Compared with the conventional tillage method, no tillage practice maintained higher soil water storage in the upper profile during the early part of the growing season. The gain was attributed to decreased evaporation losses caused by a straw stables cover and undisturbance of the surface soil under no tillage condition, as well as a change in pore size distribution in the untilled soil. On the other hand, storage in the subsoiling soil was obviously less than that of the conventional tillage soil because soil physical properties in the deep tilled soils were largely altered. As growing up of summer maize, few differences in soil water distribution were observed among the three tillage methods. The effects of different tillage methods on increase of crop yield were evident.

       

    /

    返回文章
    返回