Using a non-steady state bioaccumulation model to investigate bioenergetic processes in aquatic food webs.

目前的污染物生物积累模型假设在其环境中生物体之间实现稳态动力学。然而，这些模型不能解释在物种之间和物种内部观察到的化学体负荷的可变性。我们已经证明，稳态假设对更疏水的有机污染物是无效的，我们预测许多水生生物在其生命周期内对许多化学物质不会达到稳态，因为在基础代谢中花费的时间基本上没有能力消除化学物质。需要非稳态模型来解释在鱼类种群中观察到的污染物负荷的巨大个体差异。我们建议解决多氯联苯和汞身体负荷的个体差异是否与化学吸收或消除的差异有关。此外，我们将使用非稳态方法来确定观察到的鱼类化学物质积累的纬度模式是否与基础代谢（越冬）所花费的时间有关。这些新的非稳态模型的发展和验证将提供关于调节自然种群个体变异的过程的关键信息，并将提供观测到的纬度梯度的生态机制，在这些纬度梯度中，北极种群积累的化学物质浓度高于热带种群，尽管热带国家仍在使用许多值得关注的化学物质。

Current models of contaminant bioaccumulation assume that steady state kinetics are achieved between an organism at its environment. These models do not, however, explain the variability in chemical body burdens observed among and within species. We have demonstrated that steady state assumptions are invalid for the more hydrophobic organic pollutants, and we predict that many aquatic organisms will not achieve steady state for many chemicals within their life time as a result of the time spent at basal metabolism when essentially there is very little capacity to eliminate chemicals. Non-steady state models are required to explain the large individual differences in contaminant burdens observed within fish populations. We propose to resolve if individual differences in PCB and Hg body burdens are related to differences in chemical uptake or elimination. Furthermore, we will use a non -steady state approach to determine if the observed latitudinal patterns of chemical accumulation in fish are related to the amount of time spent at basal metabolism (overwintering). Development and verification of these novel non- steady state models will provide critical information on the processes the regulate individual variability in natural populations and will also provide an ecological mechanism for the latitudinal gradients observed where arctic populations accumulate higher chemical concentrations than tropical populations even though many of the chemicals of concern remain in use in tropical countries.