Seasonal variations of Cinnamomum burmanii photosynthetic traits in karst hills

Vegetation restoration was an effective approach of ecosystem rehabilitation in karst area. Selecting tree species well adaptive to karst environment and ascertaining their ecophysiological traits had a vital significance. We investigated photosynthetic diurnal changes of the dominant species Cinnamomum burmanii in the four seasons on the karst hill. Both the main photosynthetic parameters, such as net photosynthetic rate, transpiration rate, stomatal conductance, water use efficiency, and some environment factors, such as photosynthetic active radiation, air temperature, relative humidity, were measured. It showed the photosynthetic traits of C. burmanii had seasonal variations to make the plant adaptive to the droughty and high temperature environment and keep high photosynthesis in karst hills. Based on exploring the photosynthetic and water use characteristcs, this study provided important theoretical foundation and scientific data for revealing the ecological adaptation mechanism of C. burmanii to karst envirionment and developing strategies of vegetation restoration in karst area.