三峡水库小江流域消落区土壤的理化性状

2009年5月、7月和9月对小江流域上游至下游消落区的5个断面的土壤理化性状进行监测。结果表明,土壤容重、孔隙度、pH、有机质、全氮和全磷的总体平均值分别为1.47g/cm3、45%、7.33、16.42g/kg、0.79g/kg和0.59g/kg,变化范围分别为1.15～1.68g/cm3、37.0%～61.0%、4.04～8.72、6.64～35.69g/kg、0.40～1.42g/kg和0.36～0.94g/kg。高程150m处的土壤容重均值在7月下降、9月增加,160m处的土壤容重均值在7月增加较多,9月变化不大;不同高程处的孔隙度均值变化与土壤容重变化呈相反的变化趋势;高程160m处土壤有机质在7月有所下降,9月变化不大;各高程土壤全氮和全磷总体呈7月升高、9月下降趋势。并对消落区土壤理化性状变化的影响因素进行了初步分析。

Soil Physical and Chemical Properties in Water-level-fluctuation Zone in Xiaojiang Watershed in Three Gorges Reservoir

In 2009,fixed-location monitoring for soil physical and chemical properties was made in water-level-fluctuation zone in Xiaojiang Watershed at 5 investigation sites from the upper reaches to the lower reaches in May,July and September.The results showed that the mean values and variation ranges of bulk density,total porosity,pH,Organic Matter（OM）,TN and TP were 1.47（1.15-1.68）g/cm3,45%（37.0%-61.0%）,7.33（4.04-8.72）,16.42（6.64-35.69）g/kg,0.79（0.40-1.42）g/kg and 0.59（0.36-0.94）g/kg respectively.At the elevation of 150 m,the mean value of soil bulk density decreased in July and increased in September;at the altitude of 160 m,mean value of soil bulk density increased in July and changes little in September;basically,the mean value change of soil total porosity at different elevation was opposite to soil bulk density.At the elevation of 160 m,the mean value of soil OM decreased in July,and changed little in September;Soil TN and TP at each elevation tended to increase in July and decline in September.At last,preliminary analysis of influence factors causing soil physical and chemical properties changes in water-level-fluctuation zone was carried out.