GEOCHEMICAL MONITORING O F ANTARCTIC LAKES AND THEIR ECOSYSTEMS

• Main Author: Genki I. Matsumoto
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Antarctic; Orga; Antarc*
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.566.754; http://polaris.nipr.ac.jp/~penguin/polarbiosci/issues/pdf/1994-Matsumoto.pdf

Abstract: The monitoring of climatic changes, water quality, human activity, biomass, biological composition and biological activity in Antarctic lakes and their ecosystems is discussed from a geochemical viewpoint. The changes in lake water levels, ice thickness and the periods of total melting and freezing of lake ice probably reflect climatic changes at the lake sites. Temperature, electric conductivity, pH, dissolved oxygen and redox potential in lake waters could be monitored continuously. Total organic carbon and petroleum-derived hydrocar-bons (such as gasoline, diesel fuels and lubricating oils) could be reflecting human activity in Antarctic lakes near research stations. Chlorophyll-a and/or fatty acid concentrations in lake waters may be useful as markers of biomass. Direct microbial observation by naked eye and/or microscope, culture of orga-nisms, and measurement of biomarkers such as hydrocarbons, fatty acids and sterols are important to monitor biological composition in the lake. Also, 16s rRNA profile may be a useful marker of biological composition. Uptake of 14C labeled compounds and/or DNA synthesis probably reflect biological activity. Normal alkenoic acid/n-alkanoic acid ratios may reflect the degree of degrada-tion of organic matter in the lake. Trandcis-CIA:, alkenoic acid ratios could be used as a starvation or stress lipid index in natural environments. 1.