Influences of fence on soil microbial biomass carbon and nutrient in mountain desert grassland

The combined methods of soil investigation sampling and lab analysis were explored on desert grassland in the North slope of Bogurda mountain. The variations of soil microbial biomass carbon and nutrient were analyzed under the free grazing and fence to investigate the influence of long-term fencing on soil quality. The results showed that, compared with free grazing, the content of soil organic carbon, available nitrogen, available potassium, and Olsen-P of fence for seven years significantly increased in the 0-10 cm layer, and the content of total nitrogen significantly increased in the 10-20 cm layer. The soil microbial biomass carbon content of fence for seven years significantly exceeded that of free grazing at the same soil layer(P0.05). Soil microbial biomass carbon was more sensitive to fence which could be used as a sensitive indicator to measure changes of soil organic carbon.