Accumulation of trace elements by invertebrates

加拿大是镉、铜和镍等微量金属的全球主要生产国。在加拿大地盾许多矿山和冶炼厂附近的湖泊和河流中发现了高浓度的此类金属。为了进行环境风险评估，环境管理人员需要能够评估污染程度和衡量对水生生物不利影响的工具。这些工具应基于对这些污染物的化学性质和所涉生物的生物学的充分了解。我和我的学生将讨论几个对开发此类工具很重要的主题。举例来说：我们将测量金属的吸收和损失，以及这些污染物对生活在自然界中的动物的毒性影响;我们将确定生物是否主要从沉积物或水柱中获得营养物质和污染物，以便设计保护水生生物的适当标准;我们将进行旨在解释为什么一些动物在高酸性湖泊中积累很少的金属的实验。这些问题的答案和其他问题将帮助我们设计可靠的模型来预测水生生物中的金属浓度以及这些污染物对水生生物的影响。我们将使用多种方法的组合，以确保我们的结论既符合实际（实地收集和湖泊实验），又基于对潜在机制的了解（实验室实验），以便它们可以外推到其他金属，生物和水生系统。

Canada is a major global producer of trace metals such as cadmium, copper and nickel. Such metals are found in high concentrations in lakes and rivers located in the vicinity of many mines and smelters on the Canadian Shield. To conduct environmental risk assessments, environmental managers require tools that will allow them to assess contamination levels and measure adverse effects on aquatic organisms. Such tools should be based on a sound knowledge of the chemistry of these pollutants and the biology of the organisms involved. My students and I will address several topics important to the development of such tools. For example: we will measure the uptake and loss of metals as well as the toxic effects of these contaminants on animals living in nature; we will determine whether organisms obtain their nutrients and contaminants mainly from sediment or from the water column so as to design appropriate criteria for protecting aquatic life; we will conduct experiments designed to explain why some animals in highly acidic lakes accumulate little metal. The answers to these and other questions will help us design reliable models for predicting metal concentrations in aquatic organisms and the impact of these contaminants on aquatic life. We will use a combination of approaches to ensure that our conclusions will be both realistic (field collections and experiments in lakes) and based on a knowledge of underlying mechanisms (laboratory experiments) so that they can be extrapolated to other metals, organisms, and aquatic systems.