RESPIRATORY ACTIVITY OF SOME LICHEN SPECIES - REPRESENTATIVES OF THE ANTARCTIC FLORA
M. A. Shelyakin1, M. P. Andreev2, G. N. Tabalenkova1, T. K. Golovko1
1Institute of Biology of Komi Scientific Centre of the Ural Branch of RAS, Syktyvkar, Russia
2Komarov Botanical Institute of RAS, Saint Petersburg, Russia
Keywords: лишайники, Антарктида, дыхание, азот, температура, lichens, Antarctica, respiration, nitrogen, temperature
Abstract
The data on the respiratory activity of 12 species of Antarctic lichens are presented. It was founded that respiration of the foliose lichens was more intensity then that fruticose lichens. The lichen respiration rate correlated positively with nitrogen content in the biomass, and depended on temperature. The thalli O2 uptake rate was increased of 2.2-2.4 times with the increasing of temperature from 5 to 15 °С. The reaction of respiration to further rise of temperature was species-specific. The decrease in the temperature coefficient of respiration ( Q 10) with an increasing temperature to 35 °С was most pronounced in the well adapted to Antarctic conditions of the endemic species Usnea aurantiaco-atra . The calculations showed that in summer daily, the lichens are able to lose in respiration the amount of substrate equivalent to 0.8-1.4 % of the thallus dry biomass. The total respiration cost of the lichen maintenance under snow during the winter can reach of 30-35 % from their biomass. The results extend our knowledge on the Antarctic lichens, and prediction their response to climatic change.
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