Metal bioaccumulation and cellular fractionation in an epigeic earthworm (Lumbricus rubellus): The interactive influences of population exposure histories, site-specific geochemistry and mitochondrial genotype

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• 作者：Jane Andre ; Stephen R. Stü ; rzenbaum ; Peter Kille ; A. John Morgan ; Mark E. Hodson
• 关键词：Earthworms ; Pb & ; Zn ; Subcellular fractionation ; Field & ; lab exposures ; Genotyping
• 刊名：Soil Biology & Biochemistry
• 出版年：2010
• 出版时间：September 2010
• 年：2010
• 卷：42
• 期：9
• 页码：1566-1573
• 全文大小：382 K

文摘

Subcellular fractionation techniques were used to describe temporal changes (at intervals from T₀ to T₇₀ days) in the Pb, Zn and P partitioning profiles of Lumbricus rubellus populations from one calcareous (M_DH) and one acidic (M_CS) geographically isolated Pb/Zn-mine sites and one reference site (C_PF). M_DH and M_CS individuals were laboratory maintained on their native field soils; C_PF worms were exposed to both M_DH and M_CS soils. Site-specific differences in metal partitioning were found: notably, the putatively metal-adapted populations, M_DH and M_CS, preferentially partitioned higher proportions of their accumulated tissue metal burdens into insoluble CaPO₄-rich organelles compared with naive counterparts, C_PF. Thus, it is plausible that efficient metal immobilization is a phenotypic trait characterising metal tolerant ecotypes. Mitochondrial cytochrome oxidase II (COII) genotyping revealed that the populations indigenous to mine and reference soils belong to distinct genetic lineages, differentiated by 13 % , with 7 haplotypes within the reference site lineage but fewer (3 and 4, respectively) in the lineage common to the two mine sites. Collectively, these observations raise the possibility that site-related genotype differences could influence the toxico-availability of metals and, thus, represent a potential confounding variable in field-based eco-toxicological assessments.