Benthic-pelagic coupling and Cladophora problems in large lakes

大型湖泊中的底栖-中上层耦合和刚毛藻问题

• 批准号: 355447-2007
• 负责人: Smith, Ralph
• 金额: $ 6万
• 依托单位: University of Waterloo
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2008
• 资助国家: 加拿大
• 起止时间: 2008-01-01 至 2009-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=402538
• 关键词: Benthic; pelagic; coupling; Cladophora; problems

Since the invasion of the Great Lakes by zebra mussels, many coastal areas have suffered from excessive growth of algae. The algae wash up on and foul beaches and shorelines, which effectively prevents recreational use. The algae also cause expensive interruptions to supplies of cooling and drinking water, and the decaying mats harbour potentially harmful bacteria. These problems would normally be associated with excessive levels of the key nutrient phosphorus, yet phosphorus concentrations in the lakes are generally low. We will undertake studies of how the algae manage to obtain the phosphorus they need to become a problem, and what management actions might be taken. We will use a section of the Lake Ontario north shore to test the theory that mussels enable the growth of algae by harvesting phosphorus from the water and then releasing it again near the bottom in a form the algae can use. Measurements of algal and mussel production will be combined with a three dimensional model that will allow us to calculate the relative importance of local phosphorus sources (e.g. storm drains and sewers) to the algal problem. The model will allow us to predict the effectiveness of potential management actions (e.g. further reductions in lake-wide phosphorus loading) and estimate targets for remedial action. The work will also increase our fundamental understanding of nearshore ecology in the Great Lakes as they continue to experience biological invasions and other stresses.

自从斑马贻贝入侵五大湖以来，许多沿海地区都受到藻类过度生长的影响。藻类冲刷并污染海滩和海岸线，这有效地阻止了娱乐用途。藻类还会造成冷却和饮用水供应的代价高昂的中断，而且腐烂的垫子里藏有潜在的有害细菌。这些问题通常与关键营养物质磷的水平过高有关，但湖泊中的磷浓度通常较低。我们将研究藻类如何设法获得它们成为问题所需的磷，以及可能采取的管理措施。我们将使用安大略湖北岸的一段水域来测试这一理论，即贻贝通过从水中捕获磷，然后以藻类可以利用的形式在接近底部的地方再次释放磷，从而促进藻类的生长。对藻类和贻贝产量的测量将与一个三维模型相结合，该模型将使我们能够计算当地磷源(例如雨水管和污水渠)对藻类问题的相对重要性。该模型将使我们能够预测潜在管理行动的有效性(例如，进一步减少全湖磷负荷)，并估计补救行动的目标。这项工作还将增加我们对五大湖近岸生态的基本了解，因为它们继续经历着生物入侵和其他压力。