关键词: 山西省暖性草地, 碳密度, 区域差异

Abstract: Grassland in Shanxi Province is an important part in the accurate estimation of grassland carbon reserves in China. By investigating and measuring the community characteristics and carbon density of warm-temperate grassland in two climatic regions of Shanxi (including the semi-arid area in northwest Shanxi and the semi-humid area in southeast Shanxi),the regional differences of ecosystem carbon density of warm-temperate grassland in Shanxi were analyzed. The results showed that the environmental differences in different climatic regions affected the diversity of grassland plants,biomass accumulation and soil carbon input,and the main environmental factors causing the difference of carbon density in the two climatic regions were precipitation and soil organic carbon content. The average plant diversity index of northwest Shanxi was slightly higher than that in southeast Shanxi. The average aboveground biomass of northwest and southeast regions were 384.28 g·m^-2 and 522.83 g·m^-2,respectively,and the average belowground biomass were 1 411.02 g·m^-2 and 1643.81 g·m^-2,respectively,both of which were lower in the region of northwest than that in southeast Shanxi. The average carbon densities of ecosystems were 7 911.48 g·m^-2 and 9 080.43 g·m^-2 in northwest and southeast regions,respectively. The proportions of vegetation,root system and soil carbon density were 1.4%~2.1%,12.3%~24.7% and 73.6%~85.9%,respectively. The carbon density of the warm temperate shrub-tussock ecosystem in southeast Shanxi was the highest,at 10 102.23 g·m^-2.

Key words: Warm-temperate grassland, Carbon density, Regional difference