DIURNAL AND SEASONAL CO2 EXCHANGE ON CLEAR DAYS IN A TROPICAL SEASONAL RAINFOREST OF XISHUANGBANNA Variation in net CO2 exchange, gross primary production and its affecting factors in the planted pasture ecosystem in Sanjiangyuan Region of the Qinghai-Tibetan Plateau of China Annual Carbon Dioxide Flux Variations of Alpine Shrub Ecosystem in the Qinghai-Tibet Plateau Effects of CO2 storage flux on carbon budget of forest ecosystem. CO2 fluxes and their driving factors over alpine meadow grassland ecosystems in the northern shore of Qinghai Lake, China Effects of reclamation on net ecosystem CO2 exchange in wetland in the Yellow River Delta, China