Evaluation Of Ecological Security In Jinshajiang Area In Central Yunnan Province Based On RS And GIS

The deterioration of the ecological security situation in China has caused great restriction on the sustainable development of social economy,so the maintenance of ecological security has become a major event in front of us.Ecological security is the foundation of national security,and it is also the research focus in the field of ecology and geology and other areas.Jinsha River is the source of the Yangtze River,its ecological security not only affects the social and economic development of the Jinshajiang area in central Yunnan Province,but also has a great impact on the middle and lower reaches of the socio-economic development.Therefore,the evaluation of ecological security in the Jinshajiang area in central Yunnan Province is conducive to further understand the safety state of the local ecological environment system,and also to provide a guarantee for the sustainable development of regional ecological environment and social economy.It is of great significance.In this study,using the Landsat series of remote sensing images,social statistics data and field survey data in 1988,1996,2000,2005,2010 and 2015,and supported by RS,GIS and GPS,and combining the actual situation of the Jinshajiang area in central Yunnan Province and the data reliability and accessibility,and according to the pressure-hidden risk-response model which was established through the principle of ecological security evaluation and the pressure-state-response framework,16 characteristic indexes were selected to construct the evaluation index system of ecological security that are obtained from the aspects of stress,hidden trouble and response.And the evaluation index system of ecological security can reflect the state of ecological security in Jinshajiang area in central Yunnan Province from the corresponding level and scale.The weight of the evaluation index system was determined by using the Analytic Hierarchy Process(AHP),the entropy method and the comprehensive index method.The ecological security of the Jinshajiang area in central Yunnan Province from 1988 to 2015 was evaluated quantitatively.The main contents and conclusions are as follows:(1)Using the Analytic Hierarchy Process,the entropy method and the comprehensive index method to determine the weight of the evaluation index system,the weighting values of the stress factors,the hidden risk factors and the response factors are 0.2828,0.0738 and 0.6434 respectively.From the weighting values of the evaluation index system,the response factors has the greatest contribution to the ecological security of the study area,followed by the stress factors,and finally the hiadden risk factors,which can provide direction for taking specific measures to protect the ecological security direction of the Jinshajiang area in central Yunnan Province.It should start by relieving the pressure of the ecological environment in the Jinshajiang area in central Yunnan Province,supplemented by mitigating the hidden dangers of the ecological environment and guiding the national response to the protection of ecological environment policy.(2)After standardized treatment of the index data of Jinsha river in central Yunnan Province,the ecological security comprehensive index values of the total ecosystem assessment system of Jinshajiang area in central Yunnan Province at six points of the 1988,1996,2000,2005,2010and2015 were 25.58849,20.22379,22.27450762,20.35786847,21.40643 and 21.55728 respectively by using spatial superposition and weighted summation method.From the time point,the ecological security index value of Jinshajiang area in central Yunnan Province was declining in volatility,and ecological security has always belonged to the ecologically fragile area in extremely unsafe state.However,after 2005,the ecological security situation gradually improved,and the gaps of the ecological security situation in each county of the Jinshajiang area in central Yunnan Province were gradually narrowed,and the ecological security situation of the whole region gradually converged,which is beneficial to the corresponding counter measures to improve the ecological environment of the whole Jinshajiang area in central Yunnan Province.(3)The ecological security index values of the pressure subsystem,the hidden danger subsystem and the response subsystem were calculated respectively.The calculated results were as follows: the ecological secueity comprehensive index values of pressure subsystem of the six points were 9.44954375,14.17359163,12.49034908,13.79916977;and the ecological security index values of the hidden danger subsystem were 10.14792,7.064268,8.900081,8.061351,8.206549 and 8.835166;and the ecological security index values of the response subsystem is 34.45328,24.39253,28.10912,24.65113,25.38232 and 27.06323.The results show that the index values of the pressure subsystem was slightly undulating at all time points,but the overall increased in the period from 1988 to 2015.The ecological security index values of the hidden danger subsystem showed the state of “decreasing-increasing-decreasing – increasing”,and overall decreased.The ecological security index values of the response subsystem in 2005 as the turning point showed the state of “decreasing-increasing”,and the situation of ecological environment which was continued to be damaged in the Jinshajiang area in central Yunnan Province was improved year by year after 2005.In general,the eco-environmental load in the Jinshajiang area in central Yunnan Province is increasing and the vulnerability is more and more strong,but the state of ecological environment is improved and the self-recovery ability of the ecosystem is enhanced.(4)The changes of the comprehensive index values of ecological security from large to small in the seven counties in the Jinshajiang area in central Yunnan Province from 1988 to 2015 were Luquan County(8.384896),Dayao County(6.620817),Dongchuan District(1.357159)Yuanmou County(-4.25271),Wuding County(-5.34766),Yongren County(-21.5185),Huize County(-13.4624).The results show that the spatial differences of ecological security development in the Jinshajiang area in central Yunnan Province from 1988 to 2015 are obvious,and the ecological environment of the three counties that are Luquan County,Dayao County and Dongchuan District has been improved,and the ecological environment of Luquan County was the biggest;and the ecological security situation of the four counties and districts of Yuanmou County,Wuding County,Yongren County and Huize County was further deteriorated,and effective measures are immediately needed to protect and improve the local ecological environment.