宽地膜覆盖条件下土壤温度场特征

宽地膜覆盖对土壤温度有明显的正效应。通过对新疆奎屯地区某地宽地膜覆盖条件下地温场动态的分析，可知膜间、膜边、膜中和揭膜4种处理下的土壤表层5cm处的温度（以下称表层土温）都可以拟合为时间的正弦函数；温度的日变化特征可以用8：00，16：00，20：00三个时刻来简要表征；种植季节内表层土壤最高温度、表层土温最大变幅及平均表层土温的最大值均发生在膜中，其后依次为膜边，膜间与揭膜；膜中、露地和膜间的不同深度地温在一日内和种植季节内均有一个变化过程；一日内地温度变幅与深度关系可拟合成指数函数。

Field Characters of Soil Temperature Under the Wide Plastic Mulch

Wide plastic film mulch has demonstrated obvious positive effect on soil temperature. A field experiment was conducted in Kuitun, Xinjiang, to investigate soil temperature dynamics for four scenarios: three within the mulch (clearance, middle and side), and one with the mulch removed. The variation of upper layer soil temperatures (5 cm deep) can be fitted as a sine function, and the daily variation can be characterized by three measurements at 8:00,16:00 and 20:00. For the upper layer soil in the planting season, the maximum temperature, maximum temperature fluctuation, and maximum average temperature all occurred under the middle of the mulch, which was followed in turn by the side and clearance of the mulch, and with the mulch removed. Soil temperatures of clearance, middle and side at different depths have their variation both in a day and in seasons. For different soil depths, the amplitude of temperature daily variation can be approximated as an exponential function of the depth.