Collaborative Research: Biogeochemistry of Dissolved Organic Matter in Pony Lake, Ross Island

溶解有机物(DOM)是水生生物系统中重要的化学成分，因为它是微生物的重要碳源，吸收阳光中的有害辐射，能够与金属络合，并参与重要的生物地球化学反应。这项研究将调查位于罗斯岛罗伊德角的南极沿海小池塘--Pony Lake中DOM的生物地球化学循环。因为这个地方没有高等植物，所以这个湖里所有的DOM都来自微生物。因此，小马湖是研究物理、化学和微生物过程对DOM池的组成和特征的影响的理想地点。最后，小马湖也是收集国际腐植物质协会(IHSS)富里酸标准的理想地点。与其他IHSS标准不同的是，该标准不包含从高等陆地植物中提取的DOM成分。为了更好地了解物理影响的作用，该项目将研究DOM池在夏季从有冰到无冰的演变过程中的变化，以及DOM与观测到的湖泊中优势微生物群落更替的关系。科学家还将监测冰向开阔水域过渡期间可能发生的微生物丰度、多样性和生产力的变化。这项研究将提供关于微生物多样性和DOM生物地球化学之间关系的迫切需要的信息。当科学家在实地和实验室时，中学理科学生将通过互联网积极参与这个项目。

Dissolved organic matter (DOM) is a significant chemical component in aquatic systems because it acts as an important carbon source for microorganisms, absorbs harmful radiation in sunlight, is able to complex metals, and can participate in important biogeochemical reactions. This study will investigate the biogeochemical cycling of DOM in a small coastal Antarctic pond, Pony Lake, located on Cape Royds, Ross Island. Because there are no higher plants present at this site all of the DOM in this lake is derived from microorganisms. Thus, Pony Lake is an ideal site to study the effect of physical, chemical, and microbial processes on the composition and character of the DOM pool. Finally, Pony Lake is also an ideal site to collect an International Humic Substances Society (IHSS) fulvic acid standard. Unlike other IHSS standards, this standard will not contain DOM components derived from higher land plants. To better understand the role of physical influences, the project will study the changes in the DOM pool as the lake evolves from ice-covered to ice-free conditions during the summer, as well as the relationship of DOM to the observed turnover of dominant microbial communities in the lake. Scientists will also monitor changes in microbial abundance, diversity, and productivity that may occur during the ice to open-water transition period. This research will provide much needed information regarding the relationship between microbial diversity and DOM biogeochemistry. Middle school science students will be active participants in this project through the Internet, while scientists are in the field, and in the lab.