Abstract: Aims Forest is an important pool of carbon in terrestrial ecosystems. Woody tissues contribute much biomass, and their
respirations influence carbon fixation. Stem respiration is an important component of the carbon budget of forest stands.
Stem respiration has been studied in temperate and boreal zones, but seldom has been reported for tropical rain forests. Our
objective was to investigate the characteristics of stem respiration and the response of stem respiration to temperature in
11 common trees in Xishuangbanna tropical seasonal rainforest.
Methods We made in situ chamber measurements of stem respiration using an Li-820 infrared CO₂ gas analyzer (IRGA) from March
2005 to February 2006. Our custom-built polyvinyl chloride (PVC) chamber sealed to the stem by thin neoprene gaskets. Stem
respiration rates were measured on south and north sections at 1.3 m height, and stem temperatures were recorded at 1 cm
depth.
Important findings Stem respiration rates of all species had similar seasonal patterns and were higher in the wet season and
lower in the dry season. There were significant differences in stem respiration rates among species, ranging from 0.823 to
2.727μmol•m^-2•s^-1. Stem respiration rates on the south and north sections were similar for the same species. Significant
exponential correlations w ere observed between stem respiration rates and stem temperatures (0.55＜R²＜0.9 2). Q₁₀ values
for stem respiration among species ranged from 1.90 to 3.03, somewhat higher than the range (1.6-2.38) reported in previous
studies.