Disproportionate Importance of Edge Habitat for Ecosystem Functoning in Deep Oligotrophic Lakes

边缘栖息地对深层少营养湖泊生态系统功能的不成比例的重要性爱达荷州大学NSF初学者赠款(0528531)，2005年8月3日人类活动极大地改变了湖泊的许多方面；尤其是，来自化肥和污水的营养物质会鼓励滋扰藻类，移除树木可以减少遮荫，并减少掉到水面上的昆虫数量，在那里它们被湖泊动物吃掉。虽然湖岸可能构成了受人类干扰的一个相对较小的湖泊区域，但这一近岸区域往往可能是鱼类和其他动物繁殖和觅食的最关键的栖息地。在这里，将通过检查湖泊动植物组织中自然出现的稳定同位素来评估近岸环境的重要性；碳同位素可以表明生长主要是由近岸还是开阔水域的食物资源支持的，氮同位素与生物体在“食物链”中的位置有关。稳定同位素还可以帮助区分助长滋生藻类生长的不同营养污染物，以便管理人员能够更有效地进行有针对性的监测和控制。对海岸线的干扰可能会在湖的其他部分出现污染之前很久就影响生态系统的功能。管理人员越来越多地呼吁控制近岸污染，尽管局部性干扰在整个湖泊范围内的后果尚未得到很好的了解。这项研究将提供关于近岸环境在构建动植物群落中的作用的关键信息，并帮助确定湖泊管理和保护工作的优先顺序。

Disproportionate importance of edge habitat for ecosystem functioning in deep oligotrophic lakesStephanie E. Hampton, University of IdahoNSF Starter Grant (0528531), 3 August 2005Human activities greatly alter many aspects of lakeshores; in particular, nutrients from fertilizers and sewage can encourage nuisance algae, and tree removal can decrease shading as well as reduce the number of insects that fall to the water surface where they are eaten by lake animals. While the lakeshore may constitute a relatively tiny area of the lake disturbed by humans, this nearshore area frequently may be the most critical habitat for breeding and feeding by fish and other animals. Here the importance of nearshore environments will be evaluated through examination of naturally occurring stable isotopes in tissues from lake animals and plants; carbon isotopes can indicate whether growth is mainly supported by nearshore or open water food resources, and nitrogen isotopes relate to an organism's position in the "food chain". Stable isotopes can also help differentiate among different nutrient pollutants that fuel growth of nuisance algae, such that managers can more effectively target monitoring and control. Disturbance to the shoreline can affect ecosystem functioning long before the rest of the lake appears polluted. Managers increasingly call for controls on nearshore pollution, although lake-wide consequences of localized disturbances are not yet well understood. This research will provide critical information on the role of nearshore environments in structuring plant and animal communities and help prioritize management and conservation efforts in lakes.