The Research Of Rational Population Scale Based On The Comprehensive Carrying Capacity Of Xi'an

Since China's reform and opening up,rapid accumulation of economy and industry made the attraction which urban to population and resources strengthen gradually.With the unlimiuted expansion of city scale,the urban problems appeared continuously such as the deficiency of urban resources provision,the decrease of the living environment,the increase of living cost,and inadequate bearing capacity of the city is one of the reasons for this phenomenon.This article selected xi?an,the megacity,as research object,took 2014 as research samples,studied the concept and connotation of urban comprehensive capacity,and discussed the relationship between urban comprehensive capacity and city size,and constructed the evaluation index system of urban comprehensive capacity.On this basis,this article forecasted urban comprehensive capacity in xi?an 2020,discussed the reasonable scale of xi'an,and put forward suggestions and measures for improving the bearing capacity of urban comprehensive which aimed at the lake of of xi 'an resources environmental utilization and the social economic development.On the basis of collecting large data,this Paper got the following conclusions with combining xi "an empirical analysis and passing by the research of qualitative and quantitative.1.The urban comprehensive capacity in xi'an is low.The comprehensive score of xi "an comprehensive carrying state in 2014 is 1.55 through the research of qualitative and in a state of severe overload.2.The lack of available water resources limited the size of the xi "an city seriously.The study found that xi 'an per capita water resources is below the national average remotely,even below the internationally recognized serious poverty line.Available water resources is smaller relatively,that impacted the ability which water was supplied to people life and economic development in xi'an directly,and limited the population growth and the development of water industry,impacted the expansion of city scale indirectly.3.The lack of land resources relatively impacted the development of urban.The Qinling mountain in the south and south-east of xi'an occupied about half of the urban land area,the north was Weihe river,the west was large ancient sites of Chang'an city and so on in Han dynasty,These limited the choice of urban construction land in xi"an seriously,made the available construction land resources in xi 'an is smaller relatively,the expansion of surrounding land is more difficult,limited the expansion of city scale.4.The population scale of city is 8990?9070 thousands of xi'an in 2020.According to research,in 2020,the population scale of the resources environmental bearing capacity is 8816.4?9484.7 thousands,and bearing capacity of social economy is the population scale of the bearing capacity of Spending of social security and employment is under 9073.1 thousands.Two threshold crossing each other,but some indexes of resources environmental bearing capacity under social economy bearing capacity,so it would be produce some bad effect in future.