Start date:
Late October
End date:
Early February
Dry Valleys, Taylor Valley, Lake Hoare, Taylor Glacier, Commonwealth Glacier
Principle Investigator:
Dr Steven K Schmidt
University of Colorado
Cryoconite is a combination of dust and microbial material that can absorb solar radiation and cause localized melting when deposited on glacial surfaces. These melt areas, called cryoconite holes, become hosts to ice-bound microbe communities. Low temperatures in the Dry Valleys cause ice lids to form over the holes and entomb the communities. These lids can persist for decades. The holes melt internally each summer, and during very warm summers the ice lid can melt enough to create an open ecosystem that allows transfer of biological material and potential reorganization of the community. Through field sampling and creation of experimental cryoconite holes, researchers will investigate how the stochastic processes that guide microbial community assembly will affect patterns in biodiversity and ecosystem processes in the Dry Valleys.
Team members will travel by helicopter to field camps in the McMurdo Dry Valleys. Their primary objectives are to sample naturally occurring cryoconite holes, and to test methods of creating experimental holes. The group will work out of Lake Hoare fixed camp for the month of November. They will make helicopter day trips to sample Taylor and Commonwealth glaciers, collect microbial mat material at Green Creek, and to sample and drop equipment at their primary site, Canada glacier. They will access Canada glacier by foot and will conduct numerous sampling and experimental activities there. These activities will include: sampling naturally occurring cryoconite holes, using a hand auger to collect small ice cores and create artificial experimental holes, introducing local sediments to the experimental holes, deploying data loggers in some holes, and monitoring and sampling the experimental holes. In December, the group will return to McMurdo Station to process samples in the Crary laboratory. Laboratory activities will include: isolating microbial sediments from ice cores, incubations, DNA extractions, microscopy, and other biogeochemical analyses. The group will return to Lake Hoare fixed camp for two stays of four days each in December and January to monitor and sample the developing experimental cryoconite holes on Canada glacier.