Comparison of Photosynthetic Characteristics of 4 Dominant Tree Species in Maotai Liquor Production Area

4 dominant tree species in the Maotai liquor production area were analyzed their photosynthetic characteristics of diurnal variation in summer and winter by using a portable photosynthesis system LI－6400, and then evaluated the acclimation of these species to environment. The results showed that net photosynthesis rate (Pn) of tree species were higher in morning than those in afternoon, but dark respiration rate (Rd) and light use efficiency (LUE) had not evident changingregular.Diurnal mean values of Pn were higher in Cyclobalanopsis glauca than those in Indocalamus tessellatus, Koelreuteria bipinnata and Broussonetia papyrifera in summer. In contrast, Diurnal mean value of Pn were higher in K. bipinnata than those in C. glauca, I. tessellatus and B. papyrifera in winter. Gross Pn in summer and winter was the highest for C. glauca (690μmol/ (m2·s)) and was the lowest for B. papyrifera (535μmol/ (m2·s)). Gross Rd in K. bipinnata was higher than those in C. glauca, I. tessellatus, B. papyrifera. Gross LUE was the lowest for C. glauca. According to the parameters of photosynthetic physiology, the acclimation of these species to environment was Cglauca＞Kbipinnata＞Itessellatus＞Bpapyrifera.