不同降雨强度下剖面土壤电导率的空间变异研究

Spatial variability of soil electrical conductivity under different precipitation intensity

应用传统统计学和地统计学方法,分析了重庆市中梁山坡耕地土壤电导率在无雨、小雨、中雨和大雨4种降雨强度下的空间分布特征,并分析了不同降雨强度下土壤电导率与相关参数的相关性。结果表明：在一定条件下,土壤孔隙水电导率和土壤含水率是影响土壤电导率的主要因素;土壤电导率具有明显空间变异性,不同降雨强度下同一土层电导率差异显著,不同土层间土壤电导率差异显著;对不同降雨强度下土壤电导率的变异函数理论模型拟合精度较高,无雨条件下,土壤电导率空间具有中等或强烈空间相关性,自相关域最大,不同降雨强度下0～10cm土层土壤电导率结构比为0,10～30、30～50 cm土层结构比均有不同程度下降。

Spatial variability of soil electricity conductivity（EC） in slope farmland of Zhongliang Mountain under different precipitation intensity（no rain,light rain,miderate rain and heavy rain） was analyzed by classical statistics and geo-statistics,and the correlation of soil EC and related parameters were also processed.The results showed that in some condition,soil EC of pore water and soil water content were the two major factors affecting soil EC.The soil EC was significantly different from each other in both the same soil layer under different precipitation intensity and the soil profile.The fitting precision of semi-variance of soil EC was as high as acceptable.There was a moderate or strong spatial correlation with largest autocorrelation range of soil EC under no rain condition.The C0/（C＋C0）of soil EC in 0～10 cm soil layer was 0,while 10-30 cm and 30-50 cm of soil layer had a different degree of decreasing under rain condition.