Assessment of natural forest ecosystem services in Buerjin County, Xinjiang.

We evaluated the value of natural forest ecosystem services, based on seven ecological services (ten indices) of water conservation, soil conservation and fertility maintenance, CO2 fixation and O2 generation, nutriment accumulation, air purification, biodiversity protection, and forest recreation, with the use of Type I inventory data of natural forests in Buerjin County of Xinjiang in 2001, 2006, and 2011.Results showed that the average area of natural forests is 77 047.98 ha with 72 927.76 ha in 2001, 77 872.02 ha in 2006, and 82 816.27 ha in 2011. The average volume of natural forests was 17.511 3 million m3, 16.755 5 million m3 in 2001, 17.627 6 million m3 in 2006 and 18.150 7 million m3 in 2011. The average annual value of natural forest ecosystem services in Buerjin County was 5.034 billion RMB from an estimate of 4.180 billion in 2001 5.172 billion in 2006 and 5.750 billion in 2011. Among the various ecosystem services, the largest value is attributed to biodiversity protection, accounting for 35.59% . In contrast, the greatest increase was in the value from forest recreation, which was 36 times higher in 2006 than in 2001. The values of ecosystem services of various forest types correspond with the size of their areas. This suggests that the area, volume and value of natural forest ecosystem services in Buerjin County have significantly increased after implementing natural forest protection projects.