文蛤对重金属Cu的富集与排出特征

Accumulation and elimination of Meretrix meretrix to copper

中文关键词: 文蛤  铜  富集  排出  双箱动力学模型

英文关键词: Meretrix meretrix  Copper  Accumulation  Elimination  Two-compartment kinetic model

中文摘要:

      将文蛤暴露在不同浓度（0.005、0.010、0.025、0.05 mg/L）Cu2+溶液里35d后，移入自然海水代谢45d，测定文蛤体内Cu含量变化，研究文蛤对Cu2+的富集和排出能力。富集试验结果表明，4个处理组中暴露溶液Cu2+浓度与文蛤死亡数、死亡峰值出现时间无相关；0.025、0.05 mg/L处理组文蛤体内Cu含量增加显著；平均富集速率最高达1.765 mg/kg•d；文蛤富集Cu达到平衡时间与Cu2+浓度相关性不大。排出试验结果表明，0.025、0.05mg/L处理组文蛤体内Cu含量降低显著；最高排出率达88.7%。应用双箱动力学模型分析显示，0.01、0.025、0.05mg/L 处理组中富集参数k1、k2、BCF均随着暴露水体Cu2+浓度的增加呈先增加后减小；Cu在文蛤体内的生物半衰期较短；富集平衡状态下CAmax随着外部水体Cu2+浓度的增大而增大，基本正相关。

英文摘要:

      To investigate the capability of accumulation and elimination of Cu2+ in clam，Meretrix meretrix were exposed to different concentrations of Cu2+ for 35 days and then transferred and cultured in the natural seawater for 45d. Copper content in the tissue of M.meretrix was determined and the results showed that mortality and death peak time correlated insignificantly with Cu2+ concentration; the content of copper increased markedly in the 0.025 and 0.05 mg/L treatment group with the highest average accumulation rate of 1.765 mg/kg•d; no correlation was found between the steady-state time and concentration of Cu2+. The elimination experiment showed an obvious decrease in copper content in both 0.025 and 0.05 mg/L treatments, with the highest rate of elimination of 88.7%.According to the two-compartment kinetic model, uptake rate constant (k1), extracting rate constant(k 2) and bioconcentration factor (BCF) firstly increased and then decreased with the increase of Cu2+ in the 0.01,0.025 and 0.05 mg/L treatment group; BCF of copper was relatively small in M.meretrix; the maximal metal contents in test organism(CAmax) at steady-state was positively correlated with Cu2+ concentration in the test solution.