不同覆盖方式对新疆棉田土壤温度和水分的影响

Effect of Different Coverings on Soil Temperature and Soil Moisture Content in Cotton Field in Xinjiang

土壤温度和水分是棉花生长的重要环境因子，通过测定不同覆盖下土壤温度的变化发现，覆膜对土壤的增温效应主要表现在棉花生长前期，5月份不同程度的覆膜可使土壤温度增加0．9～2．3℃，秸秆覆盖土壤温度比无覆盖情况低3．6～6．5℃。土壤温度最大日变幅与深度可拟合成对数函数关系，且两者间有很好的相关性。在整个观测过程中秸秆和地膜覆盖对土壤都有很好的保水作用，窄膜、宽膜、全膜以及秸秆覆盖条件下土壤含水量较之裸露地可分别提高0．15％～5．01％，0．19％～5．26％，1．34％～7．71％和0．47％～4．55％。但是，覆盖秸秆在棉花的生长过程中对株高几乎没有提高作用，而不同面积的覆膜对棉花株高均有显著的促进作用。

Effects of different coverings on soil temperature and soil moisture content, which are the important environmental factors affecting cotton growth are different. After measuring soil temperature under different coverings, it is found that the temperature increase of soil covered with plastic film occurs mainly at the early stage of cotton growth, and soil temperature can be increased by 0. 9 - 2.3℃ at different covering modes in May. Temperature of soil covered with straw is 3.6 - 6.5 ℃ lower than that without covering. The maximum daily change extent and depth of soil temperature can be fitted into a logarithmic function, and there is a good correlation between them. Both plastic film mulch and straw mulch have good water retention in soil. Moisture content of soil covered with narrow and wide plastic film, completely covered with plastic film and with straw can be increased by 0.15% -5.01% , 0.19% -5.26% , 1.34% -7.71% and 0. 47% -4.55% respectively. There is almost no effect of straw mulch on cotton plant height, but the effect of plastic film on increasing cotton plant height is significant.