蚯蚓对土壤污染的指示作用及其强化修复的潜力

Earthworms As Bioindicators of Soil Pollution And Their Potential for Remediation of Contaminated Soils

从三个方面综述了蚯蚓对土壤污染的指示作用:(1)通过调查污染区土壤中蚯蚓种群的数量和结构反映土壤污染情况;(2)利用蚯蚓进行生态毒理风险评价,指示污染物对土壤生态系统可能造成的危害;(3)利用蚯蚓监测土壤污染。并阐述了蚯蚓对重金属的主要耐性机制:(1)脂质过氧化保护酶系统缓解氧化胁迫;(2)分隔、固定作用;(3)螯合解毒作用;(4)溶酶体和细胞质粒抑制重金属活性。同时,分析了蚯蚓强化污染土壤修复的潜力,认为蚯蚓可以通过改善土壤理化性质、增强微生物活性、改变污染物的活性等强化污染土壤的生物修复过程。

The ways in which earthworms perform as bioindicators of soil pollution are reviewed as follows: (1) Earthworm population in contaminated sites reflects the degree of soil pollution as a whole; (2) For ecotoxicologial risk assessment, earthworms serve as an important indicator for potential pollutants damaging the soil eco-system ; (3) Earthworms act as an early warning system in monitoring changes in soil pollution. The main mechanisms of earthworms' resistance to metal pollutants are also elaborated: (1) its lipid antioxidative enzyme system helps relieve the stress of oxidation; (2) Compartment and immobilization of metals; (3) Process of chelating and detoxicification; (4) Lysosome and cellular plasmid are activated to restrain activity of heavy metals. Meanwhile, the potential of earthworms to enhance soil bioremediation is discussed and it is believed that earthworms do so by improving physical and chemical characteristics, activating microbes, changing bioavailability of pollutants in soil.