Collaborative Research: The Biogeochemical Evolution of Dissolved Organic Matter in a Fluvial System on the Cotton Glacier, Antarctica

合作研究：南极洲科顿冰川河流系统中溶解有机物的生物地球化学演化

• 批准号: 0839027
• 负责人: Diane McKnight
• 金额: $ 30.7万
• 依托单位: University of Colorado at Boulder
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-01 至 2012-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0839027&HistoricalAwards=false
• 关键词: Collaborative; Research; Biogeochemical; Evolution; Dissolved

Dissolved organic matter (DOM) comprises a significant pool of Earth's organic carbon that dwarfs the amount present in living aquatic organisms. The properties and reactivity of DOM are not well defined, and the evolution of autochthonous DOM from its precursor materials in freshwater has not been observed. Recent sampling of a supraglacial stream formed on the Cotton Glacier in the Transantarctic Mountains revealed DOM that more closely resembles an assemblage of recognizable precursor organic compounds, based upon its UV-VIS and fluorescence spectra. It is suggested that the DOM from this water evolved over time to resemble materials present in marine and many inland surface waters. The transient nature of the system i.e., it reforms seasonally, also prevents any accumulation of the refractory DOM present in most surface waters. Thus, the Cotton Glacier provides us with a unique environment to study the formation of DOM from precursor materials. An interdisciplinary team will study the biogeochemistry of this progenitor DOM and how microbes modify it. By focusing on the chemical composition of the DOM as it shifts from precursor material to the more humified fractions, the investigators will relate this transition to bioavailability, enzymatic activity, community composition and microbial growth efficiency. This project will support education at all levels, K-12, high school, undergraduate, graduate and post-doc and will increase participation by under-represented groups in science. Towards these goals, the investigators have established relationships with girls' schools and Native American programs. Additional outreach will be carried out in coordination with PolarTREC, PolarPalooza, and if possible, an Antarctic Artist and Writer.

溶解的有机物（DOM）包含地球有机碳的大量池，使生物生物体中存在的数量相形见war。 DOM的性质和反应性尚未很好地定义，并且尚未观察到自动dom在其淡水中的前体材料中的演变。最近在跨抗山脉棉质冰川上形成的冰川上流的采样显示DOM与基于其UV-VIS和荧光光谱的可识别前体有机化合物的组合更相似。提出，这种水的DOM随着时间的流逝而演变为类似于海洋和许多内陆地表水中的材料。系统的瞬时性质，即季节性改革，也可以防止大多数地表水中存在的难治性DOM的任何积累。因此，棉花冰川为我们提供了一个独特的环境，可以研究前体材料的DOM形成。跨学科团队将研究该祖细胞DOM的生物地球化学以及微生物如何修改它。通过关注DOM的化学成分，因为它从前体材料转移到更谦卑的部分，研究人员将将这种过渡与生物利用度，酶活性，社区组成和微生物生长效率联系起来。该项目将支持各个级别的教育，K-12，高中，本科生，研究生和大赛，并将增加代表性不足的科学群体的参与。为了实现这些目标，调查人员已经与女子学校和美国原住民计划建立了关系。额外的外展将与Polartrec，Polarpalooza以及南极艺术家和作家协调进行。