Cu^2+、Pb^2+与2种除草剂单一及复合污染对蚯蚓的急性毒性

Acute Toxicity of Single and Compound Pollution of Cu2+,Pb2+and Two Herbicides to Earthworm

[目的]旨在探讨Cu^2+、Pb^2+与2种除草剂单一及复合污染对蚯蚓的急性毒性。[方法]以赤子爱胜蚓为材料,采用滤纸法测定不同浓度Cu^2+、Pb^2+与草甘膦、草铵膦单一及复合污染对蚯蚓的急性毒性。[结果]单一污染试验结果显示:Cu^2+、Pb^2+、草甘膦和草铵膦对蚯蚓急性毒性48 h-LC50分别为1.287、16.344、118.311、238.713μg/cm^2。Cu^2+和Pb^2+对蚯蚓的毒性比草甘膦和草铵膦更大,草甘膦和草铵膦对赤子爱胜蚓表现为低毒。复合污染试验结果显示,在低浓度草甘膦、草铵膦胁迫下,草甘膦、草铵膦可以降低Cu^2+、Pb^2+对蚯蚓的毒性;在高浓度草甘膦、草铵膦胁迫下,添加Cu^2+、Pb^2+可以降低草甘膦、草铵膦对蚯蚓的毒性。[结论]Cu^2+、Pb^2+与草甘膦、草铵膦复合后对蚯蚓的毒性降低是由于拮抗作用。

[Aims]This study aims to reveal the effect of acute toxicity of single and compound pollution of Cu^2+,Pb^2+,and glyphosate,glufosinate-ammonium to earthworms(Eisenia fetida).[Methods]The single and joint acute toxicity of Cu^2+,Pb^2+,glyphosate and glufosinate-ammonium to earthworms was determined by filter paper method.[Results]The results of single pollution experiment showed that the 48 h-LC50 of Cu^2+,Pb^2+,glyphosate and glufosinate-ammonium to earthworms were 1.287,16.344,118.311 and 238.713μg/cm^2,respectively.The toxicity of Cu^2+and Pb^2+to earthworms is higher than those of glyphosate and glufosinate-ammonium,indicating that the acute toxicity of glyphosate and glufosinate-ammonium was low to earthworms.The results of compound pollution experiment showed that under the stress of low concentration of glyphosate and glufosinate-ammonium,glyphosate and glufosinate-ammonium could reduce the toxicity of Cu^2+and Pb^2+.Under the stress of high concentration of glyphosate and glufosinate-ammonium,the added Cu^2+and Pb^2+could decrease the toxicity of glyphosate and glufosinate-ammonium,to earthworms.[Conclusions]The toxicity decrease of Cu^2+,Pb^2+combined with glyphosate and glufosinate-ammonium is ascribed to antagonism.