Abstract: Respiration rates of Chorthippus dubius(Zub.) were determined by use of an infrared carbon dioxide analyzer at different temperatures. All 5 nymphal instars and both sexes of adult were investigated. Results of regression analyses of dry bodyweights vs. oxygen consumption at 10-30℃ gave slope values ranging from 0.75 to 0.87. Regression analyses of oxygen consumption rates per unit of body weight showed that Krogh's formula could be applied to the nymphs in second or thirdinstars and Arrhenius' equation at the other stages. No statistically significant difference in diurnal and nocturnal respiration rates at the same temperature was observed. According to the regression equations between oxygen onsumption and temper- ature, coupled with the observations of population biomass and mean ambient air temperature, we computed the oxygen consumption by the relative population in the three plant communities. The Wightman's coefficient of 2.58 was adopted to correct the population oxygen consumption value, considering the difference of respiration of the animal in the laboratory and in the field. An oxycaloric coefficient of 20.22 (J./ml) was used to convert the oxygen consumption to calories. This resulted in the population respiration of 4.65KJ in the Aneurolepidium ehinense+Stipa grandis+Agropyron michnoi community, 3.99KJ in the Artemisia frigida community and 2.33KJ in the Aneurolepidiura chinensis community.

Key words: Chorthippus dubius——respiratory metabolism——energy expendi- ture