The size and the spatial distribution of the carbon sink of Qinghai-Tibetan plateau, is still uncertain. In China, therefore, China FLUX has been initiated using eddy covariance technique, based on CERN (China Ecological Research Net). Moreover, observations and analyses have already been conducted on the flux value of CO2/H2O and energy between three different types of vegetation and the atmosphere at the Haibei Research Station of Alpine Meadow Ecosystem, the Chinese Academy of Sciences in the North of Qinghai-Tibetan plateau. This paper mainly summarizes research advances about the characters of carbon source/sink and carbon spatio-temporal variation for alpine meadow ecosystem on Qinghai-Tibetan plateau as well as conducts some analysis of related researches in the future.
1. Carbon balance of alpine meadow ecosystem carbon
Despite the large difference in time between carbon uptake and release (carbon uptake < release time), the Kobresia humilis meadow and shrub meadow were carbon sink (78.5～192.5gCm-2yr-1and 58.5～75.5gCm-2yr-1, respectively), while swamp meadow’s annual atmospheric release is16.10～76.73gCm-2yr-1. This is probably because the ecosystem respiration at our site was confined significantly by low temperature and small biomass and usually soil moisture was not limiting factor for carbon uptake. This proves that the Kobresia humilis meadow and the shrub meadow have relatively low potential for CO2 uptake and release compared to C4 grasslands, a number of lowland grasslands, and forests. Moreover, swamp meadow has relatively high release potential.