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，由于其对人类财产的负面影响，在极端情况下对人的生命造成负面影响，因此通常被公众视为有害的。但洪水也可以通过对生态系统服务的影响间接造福人类。这项研究的目的是确定洪水对生活在河流中的鱼类和其他动物的好处和后果。它将使用一个生态系统模型——阿尔伯塔落基山麓的一系列海狸池塘——和萨斯喀彻温河上一个大的、易受洪水侵袭的三角洲来检验一个假设，即河流的浅水淹没区比河流的自由流动部分具有更高的初级生产力，生产更多更大的鱼，拥有更长的食物链。这些好处预计将被潜在有毒微量元素的高浓度所抵消，这些微量元素是由洪水从土壤和腐烂的有机物中释放出来的。