蚯蚓活动对重金属在土柱中淋溶行为的影响

采用土柱淋溶方法,以溴离子为示踪离子,研究了蚯蚓活动形成的土壤大孔隙对铜和锌离子在土柱中迁移行为的影响.运用平衡和非平衡对流-弥散模型对溴离子和铜、锌离子在不同土柱中的穿透曲线进行拟合.结果表明,蚯蚓活动形成的蚯蚓孔能够产生明显的优势流现象,这种优势流极大地加快了重金属离子在土柱中垂直向下迁移的速度.非平衡对流-弥散模型能很好地预测溴离子和铜、锌离子在蚯蚓孔土柱中的流出趋势,而平衡对流-弥散模型适合于预测溶质在对照（匀质）土柱中的流出趋势.

EFFECT OF EARTHWORM ACTIVITY ON THE TRANSPORT OF HEAVY METAL IN SOIL COLUMNS

Effects of earthworm activity on the soil macropore and preferential solute transport were investigated by applying a bromide tracer. The preferential flow of heavy metals(Cu2 and Zn2 )was evaluated by equilibrium and non-equilibrium convective-dispersion equation(CDE). Results suggested that macropore formed by earthworm induced a great preferential flow and enhanced the vertical transport of heavy metals. Non-equilibrium CDE could be used to describe the transport of Br-, Cu2 and Zn2 in both homogeneous and heterogeneous soil columns, while the equilibrium CDE was only valid for homogeneous condition.