Regional ecological security and diagnosis of obstacle factors in underdeveloped regions: a case study in Yunnan Province, China

摘要

In order to clarify regional ecological security status and formation mechanism of regional ecological security barriers in underdeveloped regions of China,we took Yunnan province as a case to evaluate its regional ecological security by using entropy matter-element model,comprehensive index and GIS spatial method,and we diagnosed its obstacle factors through obstacle degree model.We found a low overall level of regional ecological security in Yunnan.Only Kunming fell into the good level,68％ of the regions were below the critical safe level.For the vast majority of regions in Yunnan,their regional ecological security was unstable.The indexes related to per capita resources,geological and topography environment,economic,and technology were at the unsafe or dangerous level.The indexes related to urban expansion,level of income,cultivated land quality were at the level of critical safety.The indexes concerning urban management capacity,air quality and water environment were at the good or ideal level.Yunnan's regional ecological security was not good due to natural obstructive environment itself,simultaneously lower backward economic and social level restricted the ability of ecological security response to manage ragile ecological environment.The results of the composite index were roughly consistent with those of the entropy weight matter-element model.The mean values of the classification index,from high to low,were:the state index ＞ the response index ＞ the pressure index.The state index and the response index had a significant mutual promotion to each other.The regions with good composite index,state index and response index mainly distributed in the central regions of Yunnan Province.Spatial autocorrelation of regional ecological security level in Yunnan was not obvious.Water resources,economic and social development were main obstacle factors of the regional ecological security.When distinguishing with obstacle type,Kunming belonged to natural ecological environment barrier type,while other regions belonged to economic and social barrier type.