Accession Number : ADP007338

Title :   Microbiological Weathering of Silicates in Permafrost,

Corporate Author : MOSCOW STATE UNIV (USSR) DEPT OF GEOLOGY

Personal Author(s) : Kolchugina, T. P. ; Fedosova, S. P.

Report Date : MAR 1992

Pagination or Media Count : 3

Abstract : Microorganisms are known to degradate soils in temperate region. Viable microbes have been found in permafrost-zone soils, and it is of interest to determine if these organisms can participate in silicate weathering in permafrost at low temperatures. The degradation of oligoclase and hornblende when exposed to psychrophilic bacteria Aeromonas sp. at low and average temperatures was considered in this study. A sterile glycerine solution was added to sterilized soil samples to serve as a source of carbon for the bacteria and to prevent the transition of the liquid phase to a solid state. The degradation of the oligoclase at +20, +4, and -1.5 deg C was examined after 109 days of incubation; the degradation of the hornblende at +20, +4, and -8 deg C was examined after 360 days. The bacteria grew in all variants, except the sterile controls. The bacterial number at +20 deg C was 50 times more than in other non-sterile variants. The bacteria promoted the release of Ca and Na from the oligoclase and did not promote the release of Si from this mineral. The content of the Ca in the media exceeded the content of other elements.

Descriptors :   *BACTERIA, *DEGRADATION, *PERMAFROST, *SILICATES, *SOILS, CARBON, INCUBATION, LIQUID PHASES, LIQUIDS, MEDIA, MICROORGANISMS, MINERALS, NUMBERS, PHASE, REGIONS, RELEASE, SOLIDS, TEMPERATE REGIONS, TEMPERATURE, TRANSITIONS, WEATHERING, SYMPOSIA, CALCIUM, SODIUM, USSR.

Subject Categories : Geography
      Snow, Ice and Permafrost
      Microbiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE