云南省元谋干热河谷土壤水分的动态变化

用波谱分析法的研究结果表明,当地旱雨季土壤含水量差异较大:旱季土壤含水量<凋萎湿度,土壤水分严重亏缺。因受降水量的影响,土壤含水量呈周期为1a的波动变化。用谐波分析法还计算了各层次土壤含水量的谐波展开式,由此可预报土壤含水量变化趋势。

DYNAMIC VARIATION OF SOIL WATER IN YUANMOU DRY-HOT VALLEY, YUNNAN PROVINCE

The variation rules of soil water have been studied by the long-term observation on 2 soil types, i. e. typic dry red soils and vertic dry red soils in Yuanmou Dry-Hot Valley, Yunnan Province. The average contents of soil water varied greatly between dry and rainy seasons. During dry season the soil water contents are generally lower than wilting percentage,and relative water-holding capacity and guarantee rate of available water are low. It is obvious that the soil water is seriously deficient. The fluctuation of soil water contents was dealed with, employing Wave Spectral Analysis Method. The results showed that the soil water contents fluctuated pronouncedly with the period of one year due to inferior water-regulating capacity of soils,in addition,strongly influenced by the local climate,especially the precipitation. Further,by use of Harmonic Analysis Method,the Harmonic Equations of soil moisture contents of each soil layer within the soil depth of 60cm have been determined. As a result,the change tendency of soil water can be forecast.