阿克苏地区土壤温度特征分析

Characteristics of soil temperature variations in Akesu

利用阿克苏地区10个自动站2006-2008年逐时9层土壤温度观测资料,从不同的时空尺度分析其变化特征。结果发现:阿克苏地区0～20cm土壤温度存在明显的日变化,其深度每增加5cm,土壤温度最高值和最低值的出现时间分别依次向后延迟1～2小时。浅层土壤温度随深度增加日变化逐渐减小;深层土壤温度无明显日变化,且各层之间温差很小。土壤温度年变化曲线随土壤深度增加振幅减小,土壤温度最高值出现的时间随土层深度的增加而逐渐滞后,出现"右倾"现象。冬、夏季土壤温度的垂直梯度较大,而在冬夏季转换时期深层土壤温度的垂直梯度变化很小,分布均匀。阿克苏地区9层年平均土壤温度的空间分布基本类似。年平均地面最高土壤温度的分布与太阳辐射分布基本一致,随纬度的增加而减小;年平均最低土壤温度无明显的地域分布规律。自动站资料弥补了人工定时观测资料的不足,提供了土壤温度的逐时变化和深层土壤的时空分布特征,使我们能够更加全面的了解土壤温度的时空分布特征,为确定作物适宜播种期和调整种植结构提供一定的科学依据。

Based on the soil temperature data obtained from AWS in Akesu（2006-2008）,variation features of soil temperature in different depth on different sites were analyzed.The results show that： the variation of daily mean ground temperature above 20cm has a one-year period.The phase of soil temperature variation in deeper layer is lagged behind that of the shallower layer.Diurnal soil temperature decreases and the maximum temperature is lagged with the soil depth increased.Vertical gradient spatial of ground temperature is bigger in summer and winter,vertical gradient spatial of ground temperature from 0cm to 80 cm is small when cold season and warm season changes.The change of yearly climate can be shown in 80cm depth.Distribution of ground temperature from 0cm to 320cm is same basically.Contour of mean highest ground temperature is coincide with solar radiation.Mean lowest ground temperature has no obvious change in space distribution.