Directory

Start date:
2010
End date:
2010
Locations:
Lake Vida
Principle Investigator:
Dr. Peter Doran
Organisation:
University of Illinois Chicago
Lake Vida remains one of the least studied lakes in the McMurdo Dry Valleys. Researchers know that the lake has about 20 meters of ice cover over a brine that is at least seven times the salinity of seawater and below -10º C year-round. Thick sediment layers in the ice cover fully block light penetration, ensuring that any ecosystem in the brine is not photosynthetic. Samples of brine collected in 2005 from 16.5-meters down in the ice cover contain: 1) The highest nitrous-oxide levels of any natural water body; 2) anomalously high ammonia and iron; 3) high microbial counts; 4) active bacteria (indicates protein production); 5) a microbe population including an unusual proportion of ultramicrobacteria; and 6) a microbial community unique even compared to other Dry Valleys’ lakes. In this study, researchers plan to enter, for the first time, the lake’s main brine body and perform in-situ measurements, collect brine samples, and take sediment cores from the lake bottom for geochemical and microbiological analyses. 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.