河北黄壤中铅和铬(Ⅵ)对赤子爱胜蚓的毒性效应  

Toxic effects of lead and chromium(Ⅵ)on the earthworm(Eisenia fetida)in Hebei soils

作　　者：张聪 王志新 刘新会[2] 袁晓娟 ZHANG Cong;WANG Zhixin;LIU Xinhui;YUAN Xiaojuan(China Offshore Environmental Services Co.Ltd.,Tianjin,300452,China;School of Environment,Beijing Normal University,Beijing,100875,China)

机构地区：[1]中海石油环保服务(天津)有限公司,天津300452 [2]北京师范大学环境学院,北京100875

出　　处：《环境化学》2021年第6期1683-1690,共8页Environmental Chemistry

基　　金：国家重点研发计划(2019YFC1804604)资助.

摘　　要：通过向供试土壤(河北黄壤)中添加Pb(NO_(3))_(2)和K_(2)Cr_(2)O_(7)模拟受污染土壤,分别研究了Pb(NO_(3))_(2)和K_(2)Cr_(2)O_(7)对赤子爱胜蚓(Eisenia fetida)体内超氧化物酶(superoxide dismutase,SOD)、过氧化物酶(peroxidase,POD)和过氧化氢酶(catalase,CAT)活性的影响及赤子爱胜蚓对土壤中铅和铬的富集.研究结果表明,土壤中Pb(NO_(3))_(2)和K_(2)Cr_(2)O_(7)浓度和暴露时间均对蚯蚓体内Pb和Cr含量产生明显影响.暴露7 d和21 d后,蚯蚓体内Pb含量随土壤中Pb(NO_(3))_(2)浓度的增加而增加;蚯蚓体内Pb富集系数均小于1,说明赤子爱胜蚓对土壤中的Pb仅有吸收,而没有富集作用;蚯蚓体内Cr富集系数均远大于1,说明赤子爱胜蚓对土壤中的Cr具有很强的富集作用.蚯蚓对Cr的富集量要远远大于Pb,这说明赤子爱胜蚓对不同重金属的富集能力是不同的,其对重金属的富集具有一定的选择性.在测试浓度范围内(Pb(NO_(3))_(2):0-1000 mg·kg^(−1),K_(2)Cr_(2)O_(7):0-90 mg·kg^(−1)),土壤中Pb(NO_(3))_(2)和K_(2)Cr_(2)O_(7)对赤子爱胜蚓体内SOD、POD和CAT活性均产生了显著的影响,暴露1 d后,Pb(NO_(3))_(2)对蚯蚓体内3种抗氧化酶活性呈现激活作用,暴露21 d后,蚯蚓体内POD和CAT活性均随土壤中Pb(NO_(3))_(2)和K_(2)Cr_(2)O_(7)浓度的增加而降低;除此之外,3种抗氧化酶活性出现时高时低的波动,呈现不同程度的激活或抑制作用,表明其活性与土壤中Pb(NO_(3))_(2)和K_(2)Cr_(2)O_(7)浓度的剂量-效应关系不显著.Effects of Pb(NO_(3))_(2) and K_(2)Cr_(2)O_(7) on activities of three antioxidative enzymes,superoxide dismutase(SOD),peroxidase(POD)and catalase(CAT)in the earthworm,Eisenia fetida,were investigated with Hebei soils by adding Pb(NO_(3))_(2) and K_(2)Cr_(2)O_(7).The effects of earthworm accumulation of lead(Pb)and chromium(Cr)were also studied.The results showed that the heavy metal level in the soil and the exposure time both influenced the contents of Pb and Cr in the earthworm.The Pb level in the earthworm increased with increasing Pb(NO_(3))_(2) concentration in the soil after 7-days and 21-days exposure.The bioconcentration factors of Pb in the earthworms were all lower than 1,which indicated that earthworms could only absorb part of Pb rather than accumulate them.The bioconcentration factors of Cr in the earthworms were all higher than 1 after 7-days and 21-days exposure,which indicated that earthworms had strong chromium accumulation ability.The accumulation of Cr was much higher than that of Pb,suggesting that Cr could be taken up more easily by earthworms than Pb and earthworms are selective about the accumulation of heavy metals.Pb(NO_(3))_(2) and K_(2)Cr_(2)O_(7) both caused significant effects(activation or inhibition)on activities of three antioxidative enzymes.Pb(NO_(3))_(2) induced the activities of the three antioxidant enzymes in earthworms after 1-day exposure,and the POD and CAT activities decreased with the increase of Pb(NO_(3))_(2) and K_(2)Cr_(2)O_(7) concentrations in the soils after 21-day exposure.Besides,the unpredictable trends of SOD,POD and CAT activities indicating that there was no significant dose-response relationship between the activities and the concentrations of Pb(NO_(3))_(2) and K_(2)Cr_(2)O_(7) in the soils.

关 键 词：铅 铬 河北黄壤 赤子爱胜蚓 生物富集 超氧化物酶SOD 过氧化物酶POD 过氧化氢 酶CAT 

分 类 号：X171.5[环境科学与工程—环境科学] X53