Investigation And Analysis On The Biomass And Carbon Density Of Grassland In Kashgar And Kezhou Region

Grassland is an important ecosystem and occupies an important place in carbon cycle. This paper study carbon density of 4 types of grassland in Kashgar and Kezhou region using field survey and laboratory analysis. The main results of as follows:(1)Aboveground biomass range from 51.97g/m2 to 121.27g/m2 and there isn’t significant difference between four types of grasslands. In the sampling sites of lowland saline meadow and temperate desert which shrub grow, shrub biomass account for 26~96% and 15~95% of aboveground biomass respectively. So coefficient variation of aboveground biomass in lowland saline meadow and temperate desert is higher than that of alpine desert steppe and temperate desert steppe. For lowland saline meadow, alpine desert steppe, temperate desert steppe and temperate desert, litter biomass account for 17.58%, 5.74%, 9.94% and 10.74% of aboveground biomass respectively. So litter has important contribution to aboveground biomass in grassland. The herb biomass has a significant linear correlation with precipitation, but not with temperature.There is a higher belowground biomass(BGB) in alpine desert steppe than temperate desert and lowland saline meadow. There is positive correlation between belowground biomass and mean annual precipitation(MAP), but negative correlation between belowground biomass and mean annual temperature(MAT). MAP and MAT can account of 15%, 23% of spatial variety on grassland BGB in Kashgar and Kezhou region respectively. BGB is the principal to total biomass. For lowland saline meadow, alpine desert steppe, temperate desert steppe and temperate desert, BGB account for 90.71%、97.74%、97.34% and 80.24% of total biomass respectively.(2)Temperate desert(10.43kg/m2) has lower significant total carbon density than lowland saline meadow, alpine desert steppe, temperate desert steppe and temperate desert. There isn’t significant difference between lowland saline meadow, alpine desert steppe, temperate desert steppe and temperate desert, ranging from 22.21 kg/m2 to 29.42 kg/m2.Lowland saline meadow(18.11 kg/m2) and temperate desert steppe(19.45 kg/m2) have higher soil inorganic carbon than temperate desert(7.91 kg/m2) and alpine desert steppe(13.93 kg/m2).For lowland saline meadow, alpine desert steppe and temperate desert steppe, soil inorganic carbon increases slightly when depth is increased. But for temperate desert, this trend is opposite.Alpine desert steppe(10.97 kg/m2) and temperate desert steppe(10.06 kg/m2) have higher soil organic carbon. Soil organic carbon in lowland saline meadow and alpine desert steppe first increases then decline with depth increasing, but for temperate desert steppe and temperate desert, soil organic carbon increases with depth increasing.For lowland saline meadow, alpine desert steppe, temperate desert steppe and temperate desert, soil inorganic carbon account for 81.54%, 58.80%, 66.11% and75.84% of soil total carbon respectively. So soil inorganic is of great significance to carbon storage and deserve further research.(3)Soil carbon pool is the principal to carbon pool of grassland ecosystem. Primary carbon storage distribute in soil and root, especially in soil. For lowland saline meadow, alpine desert steppe, temperate desert steppe and temperate desert, soil carbon density has 37.78、20.38、33.36 and 39.70 times than biomass respectively; carbon storage in soil account for 97.42%,95.32%,97.09% and 97.54% carbon storage respectively.