[Evaluation of the forest ecosystem service values in Qinling, China]

Landsat TM images of Mt. Qinling in 1984, 2000, 2005, and 2014 were used to extract land use and land cover type by a supervised classification method in ERDAS software. Equivalent factor of ecosystem service value per unit area was revised regionally in temporal and spatial dimensions, and then was modified pixel by pixel using the vegetation coverage. Forest ecosystem service values from 1984 to 2014 were calculated with RS and GIS techniques, and the results were tested by the sensitivity index. The results showed that from 1984 to 2014, forest area accounted for 77% of the study area, and the area changes in cultivated land and construction land were the most obvious. The total ecosystem service value of Mt. Qinling increased annually and by a total of 1.68×10¹⁷ yuan during the study period. The forest ecosystem service value (its growth rate was the biggest) contributed 93.8% of the overall ecosystem service value, while water and grass ecosystem service value contributed 1.6% and 1.3%, respectively. The ecosystem service value tended to increase with increasing distance from the study area boundary, which was consistent with the spatial distribution and per-unit ecosystem service value of land use types in Mt. Qinling. The annual rate of change of each ecosystem service value was insignificant. Among the four ecosystem functions, the service value of regulation accounted for 62.7%-65.8% of the total ecosystem service value, and the service value of climate regulation showed the most dramatic increase by 4.91×10¹⁶ yuan over the study period. The sensitivity index was <1, which indicated that the modified service value index was stable and the calculated results were reliable. Overall, the forest ecosystem service value in Mt. Qinling was very large, and strengthening forest protection would be an effective measure for maintaining the stability of the Mt. Qinling ecosystem.