The Geomicrobiology of Vostok Ice: Implications for Life in Lake Vostok

最近的研究揭示了南极冰盖下的一些冰下湖泊。位于冰面下四公里的沃斯托克湖是这些湖泊中最大的，面积近一万平方公里，深度超过六百米。大约一千五百万年前，一个永久的冰盖覆盖了这个湖，使它与大气隔绝。这一跨学科项目将研究下列问题：深层冰川和吸积冰的物理应力；笼状物对湖内气体动力学的作用；吸积冰中微生物的来源；与冰结合的微生物的生理状态；冰柱(散装和冰脉内)的地球化学；以及在冰晶体基质的三重连接处形成的冰脉中的活微生物。总而言之，这项研究的结果将提供有关迄今收集到的最深冰的新信息，并允许对沃斯托克湖内的条件进行界定。考虑到从沃斯托克湖获取未受污染的样本需要付出巨大的财政和后勤努力，在尝试对实际的湖水进行采样之前，必须了解上覆冰内的条件，据推测，上覆冰为湖水提供营养物质和生物种子。收集到的信息将为无菌样本回收系统的开发和实施提供关键背景。这项跨学科研究的结果将使人们能够对沃斯托克湖的物理、化学和生物特性做出有意义的假设。

Recent studies have revealed a number of subglacial lakes beneath the Antarctic ice sheet. Lake Vostok, lying four kilometers beneath the ice surface is the largest of these lakes with a surface area near 10,000 square kilometers and a depth exceeding six hundred meters. A permanent ice sheet covered the lake about fifteen million years ago, isolating it from the atmosphere. This interdisciplinary project will examine the following: the physical stresses in deep glacial and accretion ice; the role of clathrates on gas dynamics within the lake; the origin of microbes in accretion ice; the physiological state of ice-bound microbes; the geochemistry of the ice column (bulk and within ice veins); and living microbes in ice veins that form at triple junctions in the ice crystal matrix. Collectively, results from this study will provide new information on the deepest ice yet collected and allow boundaries to be placed on conditions within Lake Vostok. Considering the enormous financial and logistic effort that will be required to obtain uncontaminated samples from Lake Vostok, it is imperative that conditions within the overlying ice, which presumably supplies the nutrients and biological seed to the lake, be understood before any attempt is made to sample the actual lake water. Information collected will provide critical background for the development and implementation of a sterile sample recovery system. Results from this interdisciplinary study will allow meaningful hypotheses to be drawn regarding the physical, chemical and biological properties of the Lake Vostok.