The potential of carbon sink in alpine meadow ecosystem on the Qinghai-Tibetan Plateau

To evaluate the potential effects of vegetation change on soil carbon storage on the Qinghai-Tibetan Plateau.We examined the soil organic carbon content of natural alpine meadow,degraded meadow,artificial pasture and farmland,and estimated the potential of carbon sequestration of the latter three types based on former natural alpine meadow.The results showed that the four vegetation types have a great difference in potential of carbon storage of 0—40 cm soil layer:(1) the carbon storage in natural alpine meadow was the highest with 17098 g C/m2,and were 5637,3823 and 1567 g C/m2 for degraded meadow,artificial pasture and farmland,respectively;(2) soil organic carbon content and density in degraded meadow and artificial pasture were significant lower than those in natural meadow and farmland;(3) root carbon storage mainly concentrated in the 0—20 cm topsoil,and the natural alpine meadow was 3.6—5 times higher than other three vegetation types.The results suggested that,there is a huge potential of carbon sink in alpine ecosystem on the Qinghai-Tibetan Plateau.