Benthic cyanobacteria in lakes and rivers: distribution, abundance, implications

湖泊和河流中的底栖蓝藻：分布、丰度、影响

• 批准号: 41839-2010
• 负责人: Cattaneo, Antonia
• 金额: $ 1.82万
• 依托单位: Université de Montréal
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2014
• 资助国家: 加拿大
• 起止时间: 2014-01-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=544889
• 关键词: Benthic; cyanobacteria; lakes; rivers; distribution

Both the scientific community and the media have recently focused on planktonic cyanobacteria because they greatly affect the use of lakes and rivers for the purposes of recreation and water consumption. Benthic species and stages are mostly ignored because they are only visible when they rise to the water surface. Nevertheless, there is increasing evidence that benthic cyanobacteria play an important role in carbon and nitrogen fixation. Moreover, they may affect the trophic chain and the water supply by interacting with invertebrates, initiating harmful planktonic blooms and releasing toxins and odour-producing metabolites. In this research, I propose to 1) quantify the still poorly understood role of physical and chemical water characteristics on the distribution and abundance of benthic cyanobacteria and 2) examine the implications of their presence for water resources. I will pursue these objectives in two environments where benthic cyanobacteria are especially relevant: A) We recently reported the presence of a significant amount of the noxious filamentous cyanobacterium Lyngbya wollei in the fluvial lakes of the St. Lawrence River, where it covers roughly 50 km2 of the river bottom. This research aims to model the temporal and spatial dynamics of L. wollei proliferation. This knowledge will be important in the management of the St. Lawrence River, as the commercial and recreational fishery may already be affected by the reduction in aquatic vascular plants and associated invertebrates linked to the spread of L. wollei. The release of toxins and taste and odour compounds may increase treatment costs for water filtration plants serving a population of several million. B) Cyanobacterial blooms are increasingly observed in several lakes of the Laurentian region north of Montréal, despite low nutrient concentrations. We will test whether these blooms initiate in the littoral zone, where benthic stages may start their growth by taking advantage of the increased nutrient supply at the sediment-water interface resulting from land development around the lakes. An understanding of the mechanisms underlying harmful blooms in recreational lakes will help preserve the quality of these important elements of Canada's heritage and water resources.

科学界和媒体最近都把注意力集中在浮游蓝藻上，因为它们极大地影响了湖泊和河流的娱乐和水的消耗。底栖生物的种类和阶段大多被忽略，因为它们只有在上升到水面时才可见。然而，越来越多的证据表明，底栖蓝藻在碳和氮固定中起着重要作用。此外，它们可能通过与无脊椎动物相互作用而影响营养链和供水，引发有害的浮游生物繁殖并释放毒素和产生气味的代谢物。在这项研究中，我建议1)量化仍然知之甚少的物理和化学水特征对底栖蓝藻的分布和丰度的作用，2)检查它们的存在对水资源的影响。我将在两个底栖蓝藻特别相关的环境中追求这些目标：A)我们最近报道了在圣劳伦斯河的河流湖泊中存在大量有毒丝状蓝藻Lyngbya wollei，它覆盖了大约50平方公里的河底。本研究旨在建立沃尔氏乳杆菌增殖的时空动态模型。这方面的知识对圣劳伦斯河的管理很重要，因为商业和休闲渔业可能已经受到水生维管植物和相关无脊椎动物减少的影响，这些植物和无脊椎动物与wollei的传播有关。毒素、味道和气味化合物的释放可能会增加为数百万人口服务的水过滤厂的处理成本。B)尽管营养物质浓度较低，但在montracimal北部的Laurentian地区的几个湖泊中越来越多地观察到蓝藻繁殖。我们将测试这些水华是否始于沿海地区，在那里底栖生物阶段可能通过利用湖泊周围土地开发导致的沉积物-水界面增加的营养供应开始生长。了解休闲湖泊中有害水华的潜在机制将有助于保护加拿大遗产和水资源中这些重要元素的质量。