Dynamic evaluation of ecological security and analysis of obstacle factors in karst tourist destinations：An example of Guilin City

Based on the ecological security theory, this paper makes a dynamic evaluation of ecological and analysis of obstacle factors in karst tourist destinations. Using the PSR model, an index system for evaluation of ecological security in karst tourist destinations is established. Using the fuzzy synthesis, the real situations of ecological security of Guilin City in 2004-2013 are analyzed as an example. The results show that the Guilin's ecological security status from 2004 to 2013 exhibited a trend from decline to gradual rise and then keeping steady, and overall upward. During this period, the unsafe level in Guilin reduced, while the critical safety level increased, with fluctuations of small amplitude, which means that the obstacle factors of Guilin ecological security were gradually decreasing and its ecosystem had a major potential of development. However, the pressure on Guilin's ecosystem is increasing year by year, implying that a caution to the trend to deteriorate in the future. The main obstacle factors of the ecological security in Guilin are the growth rate of tourism, tourist economy density and level of comprehensive utilization of the land for tourism, tourism income per capita and the proportion of environmental protection in GDP. Therefore, this study suggests the following measures to maintain the ecological security of Guilin: controlling amount of tourism, enhancing use efficiency of tourism resources, and establishing a monitoring system of the tourism environment. 