Monitoring forest and its ecosystem services value changes in Tonghua City using Landsat TM images

Based on Landsat TM remote sensing images and geoinformatical information system (GIS) technology, forestland information in the year 1986 and 2008 of Tonghua City of Jilin, China was obtained with the method of interactive interpretation. The temporal and spatial dynamic characteristics of the forest land change were analyzed during the whole study period. Forest ecosystem services value changes in Tonghua City using selected forest ecosystem services value index were evaluated. The results showed that the total area of the forestland in Tonghua decreased slightly during the past 23 years. Forestland increased, while the shrubs, sparse forestland, the other forestland decreased. The shift route of forest land gravity center showed that the consistency existed in the moving direction and the malconformation existed in the moving distance. In the functions of forest ecosystem services value, the soil conservation and fertilizer conservation value illustrated a reducing trend, while the other services value increased.