Dynamic Monitoring of Vegetation Fractional Coverage Change in the West of Jilin Province Based on Remote Sensing

The spatial and temporal distributions of vegetation are fundamental to many aspects of environmental science, global change detection and resource management. In this paper, MODIS NDVI was selected as the data source to finish the extraction of vegetation fractional coverage in Jilin from 2001 to 2008 and vegetation fractional coverage (VFC) maps from different periods using the two sub-pixel model. It also makes further analysis on the reason for the changes of VFC. It shows from the results that VFC, which is best in Songyuan, decreased gradually from northeast to southwest in the study. Over the past eight years, the overall trend of VFC in the west of Jilin had changed for two times. One is from 2001 to 2005, the trend is on the decrease, the other trend is on the rise, from 2005 to 2008, and the highest had reached 77.80% in 2005. During the period, the VFC in Tongyu had decreased least, 10.55% for eight years. The main factors affecting the changes of VFC are those, the ecological restoration engineering, the precipitation, the temperature and so on.