Are There Perennial and Light-Independent Microbial Processes on Supraglacial Ecosystems?#

冰上生态系统是否存在常年且不依赖光的微生物过程？

• 批准号: NE/V012991/1
• 负责人: Arwyn Edwards
• 金额: $ 79.6万
• 依托单位: Aberystwyth University
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FV012991%2F1
• 关键词: There; Perennial; Light; Independent; Microbial

Life thrives even on the sun-kissed surfaces of glaciers. But does life on ice survive in the darkened depths of Arctic winters and sediments?We know glacier surfaces are home to active microbial ecosystems. We know that in summer these photosynthesis-driven ecosystems fix carbon and darken ice as solar energy is converted to dark organic carbon. As a result, ecosystems on glaciers influence the fate of glaciers in our warming world. Until now, biogeochemists have assumed ecosystems on glaciers are only active when nourished with sunlight and nutrients in liquid meltwater in the brief melting season of summer. This constraint has framed our understanding of glacier surface ecology to the extent that the absence of evidence for active microbial processes on glaciers in winter has been considered evidence of their absence. But we now have year-round data which robustly challenges the assumption life is only active in summer. Our pilot data also reveals methane producers for the first time on ice surfaces. This project therefore tests the simple but powerful idea that glacier surface habitats are perennially active, resulting in unexpected sources of greenhouse gases.Our project proposes to address three interlinked major knowledge gaps in our understanding of glacier ecology. Firstly, we need to know what lives through the winter, secondly, we need to know what lives in thick accumulations of sediments on ice, and finally we need to know how the microbial life forms surviving through darkness influence carbon and nutrient cycles on glaciers. Our project's overall hypothesis is that glacier surfaces host light-independent microbial metabolic activities, thus allowing microbial activities in unexpected conditions with neglected contributions to nutrient cycles and greenhouse gas production. In this project we will go the High Arctic glaciers of Svalbard in every season to compare their microbial communities in the depths of polar night, the cold of the winter, the spring thaw and the height of summer. At each glacier we will collect samples for molecular analyses and measure microbial activities. We will conduct experiments to reveal how the microbes survive in these conditions, and how they interact with the carbon and nutrient cycles of the glaciers. We combine our fieldwork with carefully-controlled incubation experiments in cold labs in the UK, US and Norway. By doing this, we will have a clear picture for the first time of how life survives all seasons on Arctic glaciers and what this means for the ecology of Arctic glaciers as they face an uncertain future in the warming Arctic.

即使是在阳光普照的冰川表面，生命也能茁壮成长。但是，冰上的生命能在北极黑暗的冬季和沉积物中生存吗？我们知道冰川表面是活跃的微生物生态系统的家园。我们知道，在夏季，这些光合作用驱动的生态系统固定碳，并使冰变暗，因为太阳能转化为黑暗的有机碳。因此，冰川上的生态系统影响着我们这个变暖世界中冰川的命运。到目前为止，地球化学家们一直认为，冰川上的生态系统只有在夏季短暂的融化季节里，在阳光和液态融水中的营养物质的滋养下才会活跃。这一限制框架了我们对冰川表面生态学的理解，以至于没有证据表明冬季冰川上存在活跃的微生物过程，这被认为是它们不存在的证据。但我们现在有了全年的数据，有力地挑战了生命只在夏季活跃的假设。我们的试验数据还首次揭示了冰面上的甲烷生产者。因此，这个项目测试简单但强大的想法，冰川表面栖息地常年活跃，导致意想不到的温室气体来源。我们的项目提出解决我们对冰川生态学的理解中三个相互关联的主要知识差距。首先，我们需要知道什么可以度过冬天，其次，我们需要知道什么生活在冰层上厚厚的沉积物中，最后，我们需要知道在黑暗中生存的微生物生命形式如何影响冰川上的碳和营养循环。我们的项目的总体假设是，冰川表面承载着不依赖于光的微生物代谢活动，从而允许微生物在意想不到的条件下活动，而忽略了对营养循环和温室气体产生的贡献。在这个项目中，我们将在每个季节去斯瓦尔巴特群岛的高北极冰川，比较它们在极夜深处的微生物群落，冬季的寒冷，春季的解冻和夏季的高峰。在每个冰川，我们将收集样品进行分子分析和测量微生物活动。我们将进行实验，以揭示微生物如何在这些条件下生存，以及它们如何与冰川的碳和营养循环相互作用。我们联合收割机结合我们的实地考察与精心控制的孵化实验在寒冷的实验室在英国，美国和挪威。通过这样做，我们将第一次清楚地了解生命如何在北极冰川上的所有季节生存，以及这对北极冰川的生态意味着什么，因为它们在变暖的北极面临着不确定的未来。

项目成果

Icescape-scale metabolomics reveals cyanobacterial and topographic control of the core metabolism of the cryoconite ecosystem of an Arctic ice cap.

冰景规模代谢组学揭示了蓝藻和地形对北极冰盖冰晶生态系统核心代谢的控制。

• DOI: 10.1111/1462-2920.16485
• 发表时间: 2023
• 期刊: Environmental microbiology
• 影响因子: 5.1
• 作者: Gokul JK

Active and dormant microorganisms on glacier surfaces.

• DOI: 10.1111/gbi.12535
• 发表时间: 2023-03
• 期刊: Geobiology
• 影响因子: 3.7