秸秆覆盖对盐渍土水分状况的影响

EFFECTS OF STRAW MULCH ON SALINE SOIL WATER REGIME

在３种质地（砂壤、轻壤、中壤）、３种盐化程度（中度盐化、重度盐化、盐土）的土壤上进行了秸秆覆盖条件下的水分运动的模拟试验，结果表明秸秆覆盖可明显降低土壤水分蒸发，与不覆盖相比，覆盖１．５ｔ／ｈｍ２土壤水分蒸发减少量，砂壤中度盐化土为２６．８７％，砂壤重度盐化上为３９．２４％，轻壤重度盐化土为３９．３１％，轻壤盐土为４０．２０％，中壤重度盐化土为４０．２４％，中壤盐上为５５．５６％。覆盖６．７５ｔ／ｈｍ２土壤水分蒸发减少量，砂壤中度盐化土为６９．０９％，砂壤重度盐化土为７１．１８％，轻壤重度盐化土为７５．９４％，轻壤盐土为７３．８６％，中壤重度盐化土为７４．２５％，中壤盐土为８８．１３％，并且覆盖量在１．５～６．７５ｔ／ｈｍ２的范围内，土壤水分蒸发量随着覆盖量的增加而逐渐减少。

Simulation experiment of straw mulch was made on the soils with different soil texture(sandy loam, light loam, medium liam) and different soil salinity (medium salinity, strong salinity,saline soil) .The objectives of this research are to study the pursuing effects and efficiency of strawmulch on soil water evaporation reducing and try to find a new way of amelioration of coastal salinesoils.The results indiCated that straw mulch could significantly reduce soil water evaporation. As thequantity of straw increased from 1.5 t/hm2 to 6.75t/hm2, the evaporation of soil water decreased,sandy loam soil with medium salinity from 40% to 70%; sandy loam soil with strong salinity from39.24% to 71. 18%; ligth loam soil with strong salinity from 39.31% to 74.25%; ligth loam salinesoil from 40.20% to 73.86%; medium loam soil with strong salinity from 40.24% to 74. 25%,medium loam saline soil from 55.56% to 88. 3%.The efficiency of straw mulch on controlling soil water evaporation was difference differ different soil textures. Soil salinity also had effected on efficiency of straw mulch too. The results indicatedthat the efficiency of mulch on soil with medium salinity is highest, soil with strong salinity rankedsecond and the saline soil last.