This team will be able to provide a new understanding of the biogeochemical processes allowing survival of a non-photosynthetic microbial community isolated for a prolonged period of time. This study gathers a synergistic, multidisciplinary team of scientists, biologists, organic and inorganic geochemists, hydrologist, limnologist and sedimentologist. Alternatively, if this encapsulated ecosystem did not exploit its resources, it must be receiving energy from an unknown process that geochemical and microbiological analyses will help constrain.during times of thinner ice covers through stream input, aeolian deposition and subsequent fallout through the ice, and in situ photoautotrophy). This ecosystem derives its resources from ancient pools resulting from its prior coupling with the surface (e.g.An ecosystem exists in the main brine body of Lake Vida.This study will have as a guiding premise: In this study, it is proposed to enter for the first time the main brine body below the thick ice of Lake Vida and perform in situ measurements, collect samples of the brine column, and collect sediment cores from the lake bottom for detailed geochemical, sedimentological, and microbiological analyzes The results will allow the characterization of present and past life in the lake, assessment of modern and past sedimentary processes, and determination of the lake’s history. Samarkin, personal communication), 2) unusual geochemistry including anomalously high ammonia (nearly 4 mM), and iron concentrations (0.3 mM), 3) high microbial counts (106 to 107 cells per milliliter), 4) active bacteria (evidence of protein production), 5) a population of microbes including an unusual proportion (99%) of ultramicrobacteria, and 6) a microbial community that is unique even compared to other Dry Valley Lakes. Samples of brine collected in November 2005 from 16.5 m down in the ice cover contain 1) the highest nitrous oxide levels of any natural water body on Earth (Dr. Thick sediment layers high in the ice cover fully block light penetration, insuring that any ecosystem in the brine is not currently photosynthetic. It is also known that this brine has been isolated for 2,800 years. However, it is known that this lake has a ~20 m ice cover overlaying a brine of unknown depth with at least 6 times seawater salinity and temperatures below -10 ✬ year-round. Lake Vida is the largest lake of the McMurdo Dry Valleys, and yet remains one of the least studied. We’ve created these pages for you to learn about our research and adventures. This leads to a unique situation where a thick ice cover on Lake Vida requires occurrence of warm summers (and therefore more stream flow). In the summer, new water coming in from glacial streams cannot get under the ice and so it flows on top and freezes. In fact, the ice cover is so thick that water trapped under the ice is completely isolated from other environments. Unlike those lakes, Vida has an ice cover year round. Lake Vida is not a lake like those of Wisconsin or Michigan. This started a series of investigations on the history and physics behind the formation of this unusual lake, as well as on the potential for life in the brine, and how it survives. However, in 1995, ground penetrating radar surveys revealed a very salty liquid layer (a brine) underlying a 20 m (66 foot) ice cover. It was originally thought to be an ice block lake – frozen solid. Lake Vida, in the McMurdo Dry Valleys of East Antarctica, is one of the largest lakes in the region. Then, as now, the South Pole would have been subjected to four months of unyielding darkness during the Antarctic winter.Geochemistry and Microbiology of the Extreme Aquatic Environment in Lake Vida, East Antarctica They also hint something about how such a thing could have been possible.īy the team's estimates, thanks to the creeping drift of continental plates the drill site would have been several hundred kilometres closer to the South Pole back when dinosaurs still roamed. The implications of this unprecedented find don't just tell us polar plant life existed way back when. "The numerous plant remains indicate that the coast of West Antarctica was, back then, a dense temperate, swampy forest, similar to the forests found in New Zealand today," says palaeoecologist Ulrich Salzmann from Northumbria University in the UK. Microscopic analyses also found evidence of pollen and spores, all pointing to the preserved remains of an ancient rainforest that existed in Antarctica approximately 90 million years ago, eons before the landscape was transformed into a barren province of ice. Back on land, scans described an intricate network of fossilised plant roots.
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