种养结合模式下土壤重金属的含量特征

Features of Heavy Metal Contents in the Planting-breeding Combinative Recycling Model

分析种养结合循环利用模式下春秋两季土壤中重金属全量和有效态含量变化,运用多元统计和GIS及地统计等方法,对试验组(施用沼液)和对照组6种土壤重金属含量进行方差、空间格局、主成分综合评价等分析。结果表明,春秋两季试验组重金属Cd、Cu和Pb全量显著低于对照组(P<0.01);As、Cr、Cd和Cu全量不同季节差异极显著(P<0.01);土壤重金属有效态含量主要受成土母质、地形地貌等结构性因素影响;不同季节试验地土壤质量得分均优于对照地。试验结果显示,长期灌溉沼液对土壤重金属积累有明显改善作用。

The variation of heavy metal total content and available content in soil were analyzed in the recycling model of planting and breeding combination. With methods of multivariate statisticals, GIS and geostatistical etc, six kinds of soil heavy metals from the experimental group（biogas slurry irrigation） and the control group were analyzed by variance, spatial distribution and PCA. The results showed that the to- tal contents of Cd, Cu and Pb in the experimental group were lower than these in the control group in spring and autumn（P 0.01）the total contents of As, Cr, Cd and Cu revealed significant difference be- tween seasons（P〈0. 01） the available content in soil were mainly affected by the structure factors such as soil parent material and landforms the soil quality in the experimental group scored higher than that in control area in seasons. The results suggested that the soil heavy metal content sedimentation could be de- creased effectively by biogas slurry irrigation.