Microbiological and geochemical studies along the new Greenland NEEM core: from authenticity to microbial diversity and activity

“该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。“这项研究将使用示踪方法来跟踪冰芯钻探和芯后松弛期间外源微生物污染的起源和程度，以确定本地微生物多样性及其与过去气候和一氧化二氮记录的关系。该项目将在北Eemian（？NEEM？）格陵兰岛的深层冰芯具体目标和方法包括：（1）采用以下方法检测不同来源微生物污染的可能来源：对钻井液进行微生物和分子分析，通过质谱法跟踪其渗透到冰中，并通过递送荧光微球来测试潜在污染物的渗透（作为微生物替代物），并通过荧光显微镜和流式细胞术分析微球涂覆的冰芯的薄切片;（2）利用高分辨率显微镜和流式细胞技术，确定不同深度的本地微生物种群与沉积气候的关系的丰度、生存能力和多样性;（3）将35，000年至45，000年期间冰中一氧化二氮的元素和同位素组成的可能异常与特定有机体的微生物原地生产联系起来。

"This award is funded under the American Recovery and Reinvestment Act of 2009(Public Law 111-5)."This study will use tracer methodologies to track the origin and extent of exogenous microbial contamination during ice-core drilling and post-core relaxation in order to ascertain the indigenous microbial diversity and its relationship to past climates and to nitrous oxide records. The project would be conducted during the drilling of the North Eemian (?NEEM?) deep ice core in Greenland. Specific objectives and methods include: (1) Testing the possible origin of microbial contamination from different sources using the following approaches: microbiological and molecular analyses of the drilling fluid, tracking its penetration into the ice by mass spectrometry, and testing the infiltration of potential contaminants by delivering fluorescent microspheres (acting as microbial surrogates) in the borehole during particular runs and analyzing thin sections of the microsphere coated ice cores by fluorescent microscopy and flow cytometry; (2) Using high resolution microscopic and flow cytometric techniques to determine the abundance, viability and diversity of the indigenous microbial populations from different depths in relationship to deposition climate; (3) Linking possible anomalies of the elemental and isotopic composition of nitrous oxide in ice dated between 35,000 and 45,000 years to microbial in-situ production by specific organisms.