Interactive Effects of Disturbance Frequency and Species Composition on Ecosystem Functioning of Intermittent Streams: a Test of Future Climate Change Scenarios

对美国大平原地区全球气候变化的预测包括干旱持续时间的增加和洪水的严重性。 这些气候变化将伴随着水生生物的丰度和分布的变化，这是由人类对景观的改变造成的。 大平原的水生研究表明，洪水和干旱对草原溪流生态系统的状况有很大影响。 然而，气候事件的变化将与水生生物多样性的变化相结合，这些变化的组合将如何影响草原溪流生态系统目前尚不清楚。 拟议的实验将模拟气候事件的变化以及鱼类和河流昆虫等主要水生生物的丰度。使用从现场实验和控制实验流设施的观察，洪水，干旱和草原溪流水生生物的多样性的影响的特点。 这些实验将测量在不同气候变化情景下的光合生产量和溪流捕获营养物质的能力。 了解草原溪流的动态对于保护和管理这些具有重要生态意义的栖息地至关重要。 此外，当健康时，这些溪流会从周围的景观中过滤营养物质，并对水质产生强烈的影响。 拟议的研究与Konza Prairie长期生态研究（LTER）网站的一般主题一致，并将允许对整个草原生态系统的气候变化的后果进行广泛的评估。 与Konza Prairie生物站实验溪流设施相关的研究也将通过允许游客直接观察溪流生物来促进公共教育。 将通过与堪萨斯州立大学学生本科生研究机会计划和目前资助的NSF-REU网站活动的合作，促进从代表性不足的群体中招募学生。

Predictions of global climate change in the Great Plains region of the U.S. include an increase in the duration of droughts and the severity of floods. These climatic changes will be accompanied by shifts in the abundance and distribution of aquatic organisms that are caused by human modifications to the landscape. Aquatic research in the Great Plains has indicated a strong influence of flooding and drought on the condition of prairie stream ecosystems. However, changes in climatic events will be coupled with changes in aquatic biodiversity, and how the combination of these changes will influence prairie stream ecosystems is currently unknown. The proposed experiments will simulate both changes in climatic events and the abundance of dominant aquatic organisms such as fish and stream-dwelling insects. Using observations from field experiments and from a controlled experimental stream facility, the effects of floods, drought, and the diversity of aquatic life in prairie streams will be characterized. The experiments will measure the amount of photosynthetic production and the ability of streams to capture nutrients under different climate change scenarios. Understanding dynamics of prairie streams is essential for the conservation and management of these ecologically important habitats. Moreover, when healthy, these streams filter nutrients from the surrounding landscape and can have strong influences on water quality. The proposed research is consistent with the general theme of the Konza Prairie Long-term Ecological Research (LTER) site and will allow broad assessment of the consequences of climate change on an entire prairie ecosystem. Research associated with the experimental stream facility at the Konza Prairie Biological Station also will facilitate public education by allowing visitors to directly observe stream organisms. Recruitment of students from underrepresented groups will be facilitated through cooperation with the Kansas State University Student Undergraduate Research Opportunity Program and the currently funded NSF-REU site activities.