重金属复合污染重构土体剖面构型构建与优化研究

Construction and optimization of heavy metals contamination in soil reconstructed sectional configuration

在重金属复合污染区,应用隔离修复技术和土体剖面重构技术,通过土地工程手段,以重构土体剖面能够含蓄次最大降雨量和灌溉水量,满足所种植作物根系延伸的同时,又可以保护隔离层结构和功能为主要目的,对重构土体剖面构型进行构建和优化研究。在综合考虑研究区土壤类型、理化性质及水分入渗、累积能力的基础上,隔离层之上最优土体剖面构型为耕作土层厚度为30cm,土壤容重约1.3g·cm^(-3),净土层厚度不低于40cm,压实系数不小于0.83,即容重不低于1.42g·cm^(-3)。

In the heavy metal compound pollution area,the isolation and restoration techniques and land profile reconstruction techniques were applied.The structure and function of the reconstruction soil profile were protected by means of accepting the sub-maximum rainfall and the irrigation water.At the same time,the reconstruction soil profile could meet the root extension of the crop planting.Under the comprehensive consideration of soil type,physical and chemical properties,soil water infiltration as well as the accumulation capacity in the study area,the optimal soil profile above isolation layer consists of the farming soil layer and the pure land layer.Specifically,the thickness of the farming soil layer should be30 cm,and its soil bulk density should be about 1.3 g·cm^(-3).Also,the pure land layer thickness should not be less than 40 cm,and its compaction coefficient should not be less than 0.83,and its bulk density should not be less than 1.42 g·cm^(-3).