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为了探讨富营养化与疏水性有机污染物的可能相互作用,对3种双壳类及沉积物中的PCB农度(C_(PCB))数据进行了分析。它们与沉积物中的总有机碳含量(TOC_(sed))存在相关性,而后者被认为代表了采样点的营养状态。几乎所有双壳类干重及沉积物中的C_(PCB)均与TOC_(sed)呈正线性相关。就沉积物而言,这简单地反映了这些化合物与TOC的高度亲合性,而对双壳类来说,这种相关性则不易解释。双壳类中PCB的同源物浓度间的差值也与TOC_(sed)呈正线性相关。为查明这些野外数据,利用一个模型盒来模拟贫营养、中营养、富营养和超营养海洋环境中PCB的迁移转化。计算结果正确地定性预示出沉积物中C_(PCB)的变化。当水体中营养状态由贫营养上升至超营养状态时,此模型预示PCBs的逸散度下降,而不能解释野外研究数据中观测到的双壳类中C_(PCB)升高的现象。有人已经提出双壳类中PCB类型的变化可能受水体中藻类生长动态的影响。而这将有选择地加速低氯联苯的同源物从水体中流失,因而,使它们在双壳类中的浓度下降。
In order to explore the possible interaction between eutrophication and hydrophobic organic pollutants, PCB (C_ (PCB)) data of three bivalves and sediments were analyzed. They are related to the total organic carbon (TOC sed) in the sediments, which is considered to represent the nutritional status of the sampling points. Almost all bivalve dry weight and C_ (PCB) in sediments are positively correlated with TOC_ (sed). In the case of sediments, this simply reflects the high affinity of these compounds for TOC, whereas for bivalves this correlation is not easily explained. The difference in PCB congener concentrations in bivalves also positively correlated with TOC sed. To identify these field data, a model box was used to model the migration and transformation of PCBs in poor, medium, eutrophic and supra-natal marine environments. The results of the calculation correctly indicate the change of C_ (PCB) in sediments. When the nutrient status of the water body increased from lean to hyperoxic, the model predicts a decrease in the emissions of PCBs, but can not explain the increase of C_ (PCB) in the bivalves observed in the field data. It has been suggested that changes in the type of PCBs in bivalves may be affected by the dynamics of algal growth in the water. This will selectively accelerate the depletion of the homologues of low-chlorine biphenyls from the body of water, thus reducing their concentration in bivalves.