Co-Evolution of Precambrian Life and the Environment

前寒武纪生命与环境的共同进化

• 批准号: 249565-2013
• 负责人: Konhauser, Kurt
• 金额: $ 4.88万
• 依托单位: University of Alberta
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=570649
• 关键词: Co; Evolution; Precambrian; Life; Environment

Throughout Earth's history the availability of trace elements in seawater has been controlled by long-term geological processes, such as the gradual cooling of the upper mantle, changing styles of volcanism and continental composition, and the punctuated accumulation of atmospheric oxygen that fostered oxidative weathering reactions. The idea that these events may have directed microbial evolution at the enzymatic level over billions of years is relatively recent, but incredibly profound because microbiological innovations ultimately determined Earth's habitability for the more complex organisms that followed. Much of my current research programme is focused on resolving seawater composition in deep geological time, with an aim of better understanding of the co-evolution of Earth's Precambrian environment and biosphere. The basis for this research will be the coupling of field and laboratory studies. The field component consists of the collection and analyses of three contrasting marine sediments; (i) banded iron formations, (ii) black shales, and (iii) stromatolitic carbonates. Each lithology has individually been used with great success to decipher temporal variations in seawater composition. However, what has never been attempted before is an integration of datasets to provide a comprehensive picture of the paleo-nutrient landscape that, as today, should have varied along an ocean transect. I will focus on two specific time intervals: the (1) Eoarchean (4.0-3.7 Ga) when life first evolved, and (2) Neoarchean-Paleoproterozoic (2.7-2.3 Ga) when Earth first became oxygenated. The lab component will focus on designing experiments to compliment those field studies. Specifically, my goal is to (i) ascertain how ancient marine plankton survived in oceans with elevated metal concentrations and lethal influxes of ultraviolet radiation, (ii) use a combination of geochemical modelling, proteomics and genomics to elucidate the importance of bioactive metals in the origins of bacterial metallo-enzymes, and (iii) refine existing complexation models via synchrotron radiation techniques to determine the molecular mechanisms for trace metal uptake into primary BIF minerals and stromatolites in order to calibrate our rock record data.

在整个地球的历史中，海水中的微量元素的可用性受到长期地质过程的控制，例如上地幔的逐渐冷却，火山和大陆构成的变化，以及大气氧的标点积累，从而促进了氧化氧化式效果反应。这些事件可能在数十亿年以内的酶促水平上指导微生物进化的想法相对较新，但非常深刻，因为微生物创新最终确定了地球对随后更复杂的生物的可居住性。我当前的许多研究计划都集中在深层地质时期解决海水组成，以更好地了解地球前寒武纪环境和生物圈的共同发展。这项研究的基础将是现场和实验室研究的耦合。现场成分包括收集和分析三个对比的海洋沉积物； （i）带状的铁地层，（ii）黑色页岩和（iii）层状碳酸盐。每种岩性已经单独使用，以巨大的成功来破译海水组成的时间变化。但是，以前从未尝试过的是数据集的整合，以提供古营养景观的全面图景，如今，该景观应该在海洋界面有所不同。我将重点关注两个特定的时间间隔：生命首次发展时（1）eoarchean（4.0-3.7 ga），以及（2）Neoarchean-Paleoperoperozoic（2.7-2.3 GA），当地球首次被氧化时。实验室组件将着重于设计实验，以补充这些现场研究。具体而言，我的目标是（i）确定古老的海洋浮游生物如何在金属浓度升高和紫外线辐射的致命涌入的海洋中生存，（ii）使用地球化学建模，蛋白质组织和基因组学的结合来阐明生物活性金属在生物活性范围内的重要性，在综合型综合物中，（III IIIIIIIIIIIIIIIIIIIIIIIIII）（IIIIII IIIIIIIIIIIIIIII）确定痕量金属摄取到原代BIF矿物质和基质石的分子机制的技术，以校准我们的岩石记录数据。