| The report of the 19 th CPC National Congress pointed out that "ecological and environmental protection is related to the millennium plan for the sustainable development of the Chinese nation.At present,we should speed up the reform of ecological and environmental protection system,as well as the construction of a new and beautiful China,establishing firm socialist values of ecological and environmental protection,promoting the formation of a new pattern of modernization with the harmonious development of man and nature." Tibet is an important green ecological barrier for building the "two screens and three belts" of China.There are abundant grassland resources in Tibet,which are exceededly important for consolidating the ecological security pattern.However,with most grasslands locating at alpine areas,the ecological environment in Tibet is extremely fragile,To consolidate the ecological security pattern,we should constantly optimize the scheme,as well as strengthen the grassland ecological construction and protection.The International Institute for Applied Systems Analysis(IIASA)put forward the definition of generalized ecological security in 1989,that is,ecological security covers the security status of three subsystems: economy,society and nature,which are interrelated and inseparable,being combined into an artificial composite system to help people avoid hazards about life,stability,health,basic rights,survival guarantee,necessary resources,environmental adaptation as well as social order.Ecological vulnerability and risk are the essence of ecological security,in which ecological vulnerability is at the core.Therefore,vulnerability measurement is the most powerful guarantee to reduce ecological risk and consolidate ecological security.Taking the grassland in Tibet as the research object,this paper evaluates the current situation and dynamic change of ecological security in Tibet and seven cities(districts)based on the ecological footprint model,summarizing the existing problems of grassland ecological security as well as discussing the influencing factors in Tibet,puting forward policy suggestions through theoretical mechanism and Grey Relational Degree.The study has great reference value for grassland ecological security analysis in other ecologically fragile areas.The study includes the following steps and conclusions.Firstly,it summarises and comments on the current research status of ecological footprint,grassland ecological security at home and abroad,combing the relevant concepts and theoretical basis;Secondly,based on the concept of heat per unit area and "provincial hectare",the grassland balance factor of Tibet and the yield factor of seven cities(districts)in the ecological footprint model are modified.The results show that during the study period,the grassland balance factor of Tibet is basically maintained at about 0.2.Lhasa has the the largest yield factor,while the main pastoral areas,such as Nagqu maintains a low level;Thirdly,the ecological footprint model is used to calculate the grassland ecological profit and loss,footprint intensity,ecological pressure index of Tibet from2003 to 2018 and seven cities(districts)from 2009 to 2018.Through the analysis of the current situation of grassland ecological security,it is found that the evaluation result of every indicator is different:on the one hand,the grassland in Tibet is still in the state of ecological surplus,and the ecological pressure index is "very safe",but the ecological surplus continues to decrease,and the ecological pressure index has increased,On the other hand,the intensity of ecological footprint is shrinking,showing that the grassland restoration ability is strengthened and the resource utilization efficiency is improved,which is conducive to the consolidation of ecological security pattern;Among the seven cities(districts),there are the largest grassland ecological surplus and the smallest ecological pressure in the region Ngari.Nyingchi city has the highest grassland resource utilization efficiency and the strongest sustainability of the ecological security pattern.According to the above analysis,the existing problems of grassland ecological security in Tibet are put forward: from the perspective of time dimension,the overall grassland ecological pressure in Tibet increases;From the perspective of spatial dimension,the grassland restoration capacity of Nagqu,Ngari and other major pastoral areas in northern Tibet is relatively weak,so that the ecological and economic benefits need to be improved.As a consequnence,measures should be taken to protect and manage them.Fourthly,it studies the influence mechanism of grassland ecological security in Tibet.It is considered that animal husbandry economic development,social development,grassland resource storage and utilization,grassland ecological environment protection and construction can have a certain impact on grassland ecological security in Tibet;Fifth,empirical research on the influencing factors of grassland ecological security in Tibet.The entropy weight method is used to canculate the grassland ecological profit and loss,ecological footprint intensity and ecological pressure index,which obtains the comprehensive evaluation index of grassland ecological security in the reference sequence from 2010 to 2017.It is found that the grassland ecological security in Tibet has increased steadily after 2013.The prediction results of GM(1,1)Model show that the grassland ecological security in Tibet Autonomous Region has decreased slowly from 2018 to 2022,it is in a stable situation on the whole.The results show that the development of animal husbandry economy,as well as the protection and construction of grassland ecological environment are the main factors affecting grassland ecological security in Tibet Autonomous Region;Finally,based on the impact mechanism analysis in Chapter 3 and the empirical analysis in Chapter 5,this paper puts forward corresponding policy suggestions for the problems of grassland ecological security in Tibet.More vigorous development of grassland industry,seasonal animal husbandry and modern animal husbandry should be taken seriously;Adhere to ecological public welfare projects,industries with national characteristics,science,technology and education;To improve grassland ecological economic system and compensation mechanism;To strengthen the prevention and control of rodents,promoting artificial grass planting. |
