| Abstract: |
Carbon isotope compositions of Antarctic land plants are first reported. The most interesting feature is the isotope specificity of the species. For example Usnea antarctica from different locations shows relatively narrow range of the d13C-values from 222.44 to 221.29 (7 samples), Drepanocladus sp. from 224.86 to 223.49 (8 samples), and Andreaea depressincrvis from 223.87 to 223.23 (3 samples) etc. Usually, in inhabited lands and parts of the world with rich flora and developed soil, isotopic specificity of species is masked by variations of carbon isotope composition of CO2. In Antarctic conditions influence of local sources of CO2 on the isotope composition of CO2 is appeared to be minimal. Therefore the d13C-variations inherent to individual plant physiology and biochemistry can be distinguished on the background of the stable level of the atmospheric CO2 d13C-value. The latter is best to reflect the global state of the carbon cycle.
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