Primary Production in Arctic Ecosystems: Interacting Mechanisms of Adjustment to Climate Change"

本研究的目的是分析温度，光照和养分的可利用性在调节北极冻原生态系统初级生产力的几个层次的生态组织和在不同的时间尺度的作用。 这项研究是围绕三个一般性假设的机制reeulating初级生产的调整，以应对短期和长期的气候变化。 其基本思想是，在不同的生态组织层次和不同的时间尺度上，不同的机制控制着对气候的反应。 为了对气候变化对初级生产的影响作出有用的预测，需要更好地了解这些相互作用的气候变化调整机制之间的关系。 为了检验这三个一般假设，这项为期五年的研究计划将集中在阿拉斯加图里克湖潮湿的草丛苔原的一系列综合实地实验。 要研究的机制包括在生理水平上操作的机制（例如，这些因素包括：植物生长因子（光合作用）、植物整体水平（储存和再循环、分配变化和生物量周转）、物种和生态类型水平（对养分利用效率和生长率的限制）以及整个生态系统水平（气候对土壤养分供应的控制）。 该项目是国际苔原实验（ITEX）的一部分。 该项目由北极系统科学计划（ArcSS）资助。 作为长期生态研究（LTER）和陆地生态系统全球变化（GCTE）计划的一部分，与在图里克湖和其他北极地区工作的其他生态学家合作将增加这项研究的应用和影响。

The aim of this research is to analyze the role of temperature, light, and nutrient availability in regulating primary production of arctic tundra ecosytems at several levels of ecological organization and at different time scales. The research is organized around three general hypotheses about the mechanisms reeulating adjustments of primary production in response to short- and long-term variation in climate. The basic idea is that different mechanisms control the responses to climate at different levels of ecological organization and at different time scales. In order to obtain useful predictions of the effects of climate change on primary production, a better understanding of relationships between these interacting mechanisms of adjustment to climate change is needed. To test the three general hypotheses, this five-year program of research will focus on an integrated series of field experiments in moist tussock tundra at Toolik Lake, Alaska. The mechanisms to be studied include those operating at the physiological level (e.g., photosynthesis), the whole-plant level (storage and recycling, changes in allocation and biomass turnover), the species and ecotype levels (constraints on nutrient use eficiency and growth rates), and the whole-ecosystem level (climate controls on soil nutrient supply). This project is part of International Tundra Experiment (ITEX). It is funded within the Arctic System Science (ARCSS) Program. Collaboration with other ecologist working at Toolik Lake and at other arctic sites as part of the Long-Term Ecological research (LTER) and Global Change in Terrestrial Ecosystems (GCTE) programs will increase the application and impact of this research.