不同覆盖方式下蓄水坑土壤温度日变化特征研究

Daily Variation of Soil Temperature in Water Storage Pit under Different Covering Means

为了研究不同覆盖方式(无覆盖,秸秆覆盖,地膜覆盖)下蓄水坑坑内土壤温度一日内随时间的变化规律,在田间利用水银温度计和直角地温计,观测了大气温度、蓄水坑坑内空气温度、距坑壁不同距离和坑底不同深度处地温一日内动态变化过程。试验结果表明:秸秆覆盖坑内土壤温度日变化相对平稳,外界低温时有增温效应,外界高温时有降温效应;无覆盖和地膜覆盖,坑内土壤温度随着距坑壁距离的不断增大,日变幅逐渐减小,渐趋稳定;地膜覆盖较秸秆覆盖和无覆盖对坑内土壤温度具有明显的增温效应;随着蓄水坑距地表深度的不断增大,坑壁土壤温度日变幅逐渐减小,趋于稳定。

In order to study the daily variation of soil temperature in water storage pit covered by different material and means,including no mulching,covered with straw and covered with plastic film,the temperature variation,including atmospheric temperature,air temperature in water storage and soil temperature at different distance to pit wall and different depth to the bottom of pit,is observed with mercury thermometer and rectangular geothermometer.The result shows that the daily variation of temperature in the pit covered with straw is relatively smooth.When outside temperature falls,the temperature in the pit does not fall;when outside temperature rises,the temperature in the pit does not rise.The daily variation range of the temperature in the pit decreases gradually with the increase of distance to pit wall;the temperature in the pit of covered with plastic film is higher than that of covered by straw and no mulching.It also decreases gradually with the increase of the depth of water storage pit to the surface.