Ecological benefits and toxicological consequences of flooding in river ecosystems

河流生态系统洪水的生态效益和毒理学后果

• 批准号: 434943-2013
• 负责人: Jardine, Timothy
• 金额: $ 1.97万
• 依托单位: University of Saskatchewan
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=574039
• 关键词: Ecological; benefits; toxicological; consequences; flooding

Floods are natural events that are often perceived by the public as uniformly harmful because of their negative effects on human property and in extreme cases, human life. But floods can also indirectly benefit humans via their influence on ecosystem services. The goal of this research is to determine the benefits and consequences of flooding for fish and other animals that live in rivers. It will use a model ecosystem - a series of beaver ponds in the Rocky Mountain foothills of Alberta - and a large, flood-prone delta in the Saskatchewan River to test the hypothesis that shallow, flooded areas of the river have higher rates of primary productivity, produce more and larger fish and have longer food chains than free-flowing sections of the river. These benefits are expected to be offset by higher concentrations of potentially toxic trace elements that result from their liberation from soils and decaying organic matter by floodwaters. My lab will use quantitative sampling in new and old beaver ponds to draw comparisons to free-flowing river reaches and develop models that predict changes in algal, invertebrate and fish productivity at various phases of the flood cycle. Stable isotope ratios of carbon and nitrogen will be used to examine the transfer of algal and detrital organic matter to invertebrates and fishes and assess exposure pathways for trace elements. In the Saskatchewan River delta, we will collect large, old fish and use new microsampling techniques of ageing structures (micromilling, laser ablation inductively-coupled plasma mass spectrometry) to interrogate the past feeding, growth and survival of individual fish and their exposure to trace elements in relation to hydrological conditions in the river. By increasing our understanding of both positive and negative effects of the flood pulse, it will help inform the debate surrounding the restoration of natural flow regimes via dam removal and wetland re-establishment and protection.

洪水是自然事件，由于其对人类财产的负面影响以及在极端情况下，公众经常被公众认为是统一的有害事件。但是洪水也可以通过影响人类对生态系统服务的影响间接受益。这项研究的目的是确定洪水对居住在河流中的鱼类和其他动物的益处和后果。 它将使用一个模型生态系统 - 艾伯塔省落基山山麓的一系列海狸池塘，以及萨斯喀彻温省河中的大型，容易发生洪水的三角洲，以测试假设该假设，即河流的浅水地区具有更高的原发性生产率，产生更大的鱼类，并且具有更长的食物链，并且比河流较长的食物链更长。预计这些好处将被较高的潜在有毒痕量元素浓度所抵消，这些元素是由于它们从土壤中解放而导致的，并腐烂了洪水的有机物。 我的实验室将在新的和旧的海狸池塘中使用定量抽样来对自由流动的河流覆盖率进行比较，并开发模型，以预测洪水周期各个阶段的藻类，无脊椎动物和鱼类生产力的变化。碳和氮的稳定同位素比率将用于检查藻类和碎屑有机物向无脊椎动物和鱼类的转移，并评估痕量元素的暴露途径。在萨斯喀彻温省河三角洲，我们将收集大型的老鱼，并使用新的微采样技术（微米，激光消融有效耦合的血浆质谱法）来询问过去的鱼类及其在河流中的水文条件中的亲子元素的喂养，生长和生存。 通过我们对洪水脉搏的积极和负面影响的理解，这将有助于通过大坝去除以及湿地的重新建立和保护来弥补自然流动制度的辩论。