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.

洪水是一种自然事件，通常被公众认为是有害的，因为它们对人类财产甚至在极端情况下对人类生命产生负面影响。但洪水也可以通过对生态系统服务的影响来间接造福人类。这项研究的目的是确定洪水对河流中的鱼类和其他动物的好处和后果。 它将使用一个模型生态系统——阿尔伯塔省落基山山麓的一系列海狸池塘——以及萨斯喀彻温河中一个容易发生洪水的大型三角洲，来检验河流浅水淹没区初级生产力较高的假设。 ，与河流自由流动的河段相比，生产更多、更大的鱼类，并且拥有更长的食物链。这些好处预计会被较高浓度的潜在有毒微量元素所抵消，这些微量元素是由于洪水从土壤中释放出来的以及腐烂的有机物而产生的。 我的实验室将在新旧海狸池塘中进行定量采样，以与自由流动​​的河段进行比较，并开发模型来预测洪水周期各个阶段藻类、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，并评估微量元素的暴露途径。在萨斯喀彻温河三角洲，我们将收集大型老鱼，并使用老化结构的新微采样技术（微铣削、激光烧蚀电感耦合等离子体质谱法）来询问个体鱼过去的摄食、生长和生存以及它们接触微量元素的情况。与河流水文条件有关的要素。 通过增加我们对洪水脉冲的积极和消极影响的了解，它将有助于为围绕通过大坝拆除和湿地重建和保护恢复自然水流状况的辩论提供信息。