Mapping ecosystem service dynamic in Wuyuer River watershed, Northeast China from 1954 to 2000

摘要

Wuyuer River watershed is one of concentrative and extensive distribution area of inland wetlands in China. Wetland ecosystem plays an important role in maintain the ecological functions in the region. Integrating topographic maps in 1954, Landsat MSS, TM/ETM imagery in 2000 and GIS, spatial-temporal pattern in land-use and ecosystem services in middle and lower Wuyuer River were analyzed in this paper. Results showed that area of marsh decreased from 56.04 ×104 ha to 32.04×104 ha, while the area of cropland increase 24.94×104 ha from 1954 to 2000. The annual loss rate of marsh was -1.48% (from 1954 to 1976) and -0.76% (from 1976 to 2000) respectively. Marsh land were turned into dry grassland and degraded to saline-alkalined land. The grassland decreased 40.26×104 ha dramatically for having been opened up to cropland and degraded into hardly-used land. Due to the negative effect of the decline in wetlands and grassland, total values of Middle and Lower Wuyur River's ecosystem services lost 66.10×108 RMB ￥ with an extent of 14.67% between 1954 and 2000. The highest ecosystem service value centralized in the middle area, and decreased gradually to surrounding regions.