Acclimation of leaf respiration to temperature is rapid and related to specific leaf area, soluble sugars and leaf nitrogen across three temperate deciduous tree species

1. Rates of plant respiration are sensitive to temperature, and modulated by acclimation to prevailing temperature and adaptation to the climate of origin. 2. Our objective was to evaluate the rapidity and magnitude of acclimation of leaf respiration (R-d) to natural temperature events in field-grown tree seedlings and to assess inter- and intraspecific variation across seasons and years. 3. We measured R-d and associated traits of seedlings of three temperate deciduous species, Quercus alba L., Quercus rubra L. and Acer rubrum L., growing in a common garden in St Paul, Minnesota, USA. Seedlings of each species were derived from populations spanning their range from cool/dry (Minnesota/Wisconsin) to warm/moist (North Carolina/Louisiana) regions. 4. Measurements at a common temperature (24 degrees C) were made during consecutive cool- and warm-weather systems (differing by 7-10.5 degrees C) across two growing seasons. 5. R-d rates following the warmest temperatures were 62% lower, on average, than those following cool temperatures. There was little evidence that respiration per se, or its response to temperature, depended on adaptation to climate of origin. 6. Temperature, specific leaf area, and leaf soluble sugar and nitrogen concentrations were important predictors of R-d and together explained 77% of the variation across species and populations. 7. To predict forest CO2 exchange responses to global change accurately, parameters are needed that account for the acclimation of respiration to prevailing temperature.