HR: 1340h
AN: B23A-0926    [Abstracts]
TI: Extreme Environments in Tierra del Fuego, Argentina
AU: * Schultz, C
EM: cschultz@mail.arc.nasa.gov
AF: San Jose State University, Geology Department, 1 Washington Square, San Jose, CA 95192-0102, United States
AU: D'Antoni, H
EM: hdantoni@mail.arc.nasa.gov
AF: NASA Ames Research Center, Earth Science Division, MS 239-20, Moffett Field, CA 94035-1000, United States
AU: Burgess, S
EM: sburgess@mit.edu
AF: San Jose State University, Geology Department, 1 Washington Square, San Jose, CA 95192-0102, United States
AU: Zamora, J
EM: jeanette.zamora@gmail.com
AF: National Hispanic University, 14265 Story Road, San Jose, CA 95127, United States
AU: Skiles, J
EM: jskiles@mail.arc.nasa.gov
AF: NASA Ames Research Center, Earth Science Division, MS 239-20, Moffett Field, CA 94035-1000, United States
AB: The upper timberline of the Andes Cordillera on the island of Tierra del Fuego at the tip of South America is an environment subject to extreme conditions. In order to further understand this environment, ecosystem parameters were measured within two transects of the Andes at Glaciar Martial and Cerro Guanaco. The measurements included pH, soil temperature, soil moisture, nitrogen, sodium and potassium concentration, chlorophyll absorbance, and irradiance in the ultraviolet range (200-400 nm). These data comprise a survey that serves as a baseline for an intensive research program. Chlorophyll concentration and soil data were within the range of our observations at several other sites, from Lapataia Bay on the southwestern boundary with Chile, through the eastern end of Lake Fagnano. However, unusual levels of solar irradiance were found in the open sites of both transects while those in the forest exhibited lower UV values, suggesting strong absorption and/or reflection by the forest canopy. High levels of UV radiation damage important biomolecules and may be partially responsible for the presence of life forms such as the krummholz belt in the upper timberline. These UV values may be due to the effects of global ozone depletion and the ozone hole. The low temperatures, strong winds, snow and ice-covered soil and especially the exposure to UV radiation make this area an extreme environment for life.
DE: 0315 Biosphere/atmosphere interactions (0426, 1610)
DE: 0426 Biosphere/atmosphere interactions (0315)
SC: Biogeosciences [B]
MN: 2007 Fall Meeting