不同深度秸秆覆盖对滴灌棉田土壤水盐运移的影响

为探索滴灌条件下秸秆覆盖对棉田土壤水盐运动的影响,设置表层覆盖、地表下30cm覆盖和无覆盖3种处理,进行对比试验研究,结果表明,秸秆覆盖通过对土壤水分的影响间接影响了土壤盐分的运移和分布。在30cm处覆盖秸秆主要对30cm以上土壤的水分和盐分产生影响,对35cm以下的影响和表层覆盖比较接近。采用秸秆覆盖对土壤水分和盐分水平方向的运移具有一定影响,无覆盖在前期、中期和后期土壤表层盐分均最高。30cm处覆盖秸秆阻碍了35cm以下土壤毛管水的上升,从而阻止了盐分的上升。采用秸秆覆盖后,特别是在30cm深度采用秸秆覆盖,对于调控土壤水、盐变化,抑制土壤盐分上移具有积极作用。

Effect of Different Depth Straw Mulching on Soilwater Movement and Salt Transport under Saline-alkali Drip Irrigation for the Cotton

To investigate the influence of soil water movement and salt transport by the straw mulching under the drip irrigation,three treatments were establishment to compare and experiment including surface straw mulching,straw mulching at depth of 30cm from surface and no straw mulching,the results show.The straw mulching indirectly affects transportation and distribution of soil salinity through the influence of soil moisture.The straw mulching at depth of 30 cm from surface mainly affects about above 30 cm water moisture and salinity of the soil,which has the relatively approach effects on the surface mulching and below the 35 cm.To adopt the straw mulching has a certain influence on the level direction transportation of soil moisture and soil salinity,the soil surface salt content of no straw mulching respectively is maximal in the evaporation process from the early stage to later period.The rising of the soil capillary water below the depth of 35 cm was obstructed through mulching the straw at the depth of 30 cm,and then the rising of salinity was obstructed.After adopting the straw mulching,especially adopting the straw mulching at the depth of 30 cm from surface,it has positive effects on controlling the variation of soil water-salt and repressing the soil salt up.