Abstract: The eastern Qinghai-Tibet Plateau is an ecologically fragile region. Studies on the ecological security of landscape pattern in this region are helpful for promoting the sustainable development of the ecosystems and improving the stability of the Qinghai-Tibet Plateau ecosystem. In this study, the land use data of 2000, 2005, 2010, and 2015 in eastern Qinghai-Tibet Plateau were used to analyze the ecological security change based on landscape pattern. The remote sensing images were interpreted and classified by means of remote sensing technology, and the land use change was analyzed. Furthermore, the spatiotemporal variations of landscape pattern were analyzed by constructing landscape disturbance index and landscape security index. The results showed that: (1) Water body, grassland, urban and rural area, industrial and mining area, and residential area in research region showed an increasing trend, while woodland, cropland and unused land showed a decreasing trend. (2) Grassland and woodland were the dominant landscape, while urban and rural area, industrial and mining area, and residential area had higher interference, fragmentation and separation degrees. The ecological security of unused land, cropland and woodland decreased, while that of urban and rural area, industrial and mining area, residential area and waterbody increased. (3) Cropland, grassland, waterbody, urban and rural area, industrial and mining area, residential area, and unused land had always stayed in the heavy warning level, while woodland was at a relatively safe level. The overall ecological security in eastern QinghaiTibet Plateau rose first and then fell slightly, indicating that the ecological environment in this region was gradually improved and then slightly disturbed. Measures improving the ecological environment should be taken to further enhance the ecological security.

Key words: land use, landscape pattern, ecological security, eastern Qinghai-Tibet Plateau.