Respiration rate of arctic plants as related to the production process.

This work deals with two intertwined questions: (1) what are the factors underlying equally high respiration rates of arctic plants at low temperature and of temperate zone plants at 20–25°C and (2) whether this respiration feature would explain small size of the northern plants. In an attempt to answer these questions, we collected various hypotheses scattered in the current literature and experimentally examined the respiration- growth relationships by analyzing plant productivity characteristics in three representative species inhabiting Wrangel Island (lat. 71°N). The results show that the components of the production process stay in accord in the arctic plants so that their productivity characteristics at low temperatures are nearly the same as in the temperate zone plants at higher temperatures. Hence, respiration cannot account for small size of the northern plants. Upon the experimental results and general concepts for regulation of respiration, we conclude that the intense respiration of plants inhabiting cold climate regions is caused by higher metabolic demands for energy and intermediates under the northern conditions. The enhanced metabolic demands of plants at low temperature represent the main factor of intense respiration. [ABSTRACT FROM AUTHOR]