Climate-Induced Shifts in Alpine Diatom Communities: Linking Neoecological and Paleoecological Approaches to Incorporate Responses to Trophic Forcing

硅藻是一类对环境变化敏感的微小藻类。落基山脉中部和北部湖泊沉积物中的硅藻化石表明，在20世纪期间，各种环藻物种有所增加。这种增加通常被归因于气候变化，但其中涉及的机制尚未得到测试。为了破译气候变化改变硅藻群落结构的机制，古生态分析将与实验方法相结合。来自湖泊沉积物的化石记录将与树木年轮一起被用来提供关于过去2000年气候趋势的信息。将使用一系列实验室和现场实验来评估与气候有关的参数驱动这些硅藻变化的机制。拟议工作的更广泛影响包括更好地了解高山湖泊对气候变化的反应；其中许多湖泊位于国家公园和森林中，具有很高的美学和娱乐价值。这项研究将解决冰川国家公园确定的几个研究需求，因此它可能会为公园管理者提供关键信息。萨罗斯将在2009年冰川国家公园科学与历史会议上发表演讲，公众将出席该会议。调查人员还将编制一份关于结果的资源公告，作为公园气候变化系列活动的一部分。这项研究还将为两名研究生和九名本科生提供培训。

Diatoms are a class of microscopic algae that are sensitive to environmental changes. Diatom fossils from lake sediments in the central and northern Rocky Mountains indicate that various Cyclotella species have increased during the 20th century. This increase is often attributed to climate change, but the mechanisms involved have not yet been tested. To decipher the mechanisms by which climate change has altered diatom community structure, paleoecological analyses will be coupled with experimental approaches. Fossil records from lake sediments will be used along with tree rings to provide information on climate trends over the last 2000 years. A series of laboratory and field experiments will be used to assess the mechanisms by which climate-related parameters drive changes in these diatoms. The broader impacts of the proposed work include a greater understanding of the response of alpine lakes to climate change; many of these lakes are located in national parks and forests and have high aesthetic and recreational value. This research will address several research needs identified by Glacier National Park, hence it will potentially provide critical information to park managers. Saros will speak at Glacier National Park's 2009 Science & History Conference, which is attended by the public. The investigators will also develop a Resource Bulletin on the results as part of the park's series on climate change. This research will also provide training for two graduate and nine undergraduate students.