Temp-spatial Distribution Of Chinese Population And Changes Over 75 Years

The population is the main body of the society, has the characteristics of multiple social relations and complex, it exists in a certain space and time, with distinct characteristics of the time and space.Of all the social factors in the life with the process of population development is relevant, like social activities, social relations, social phenomena and social problems.For thousands of years, temp-spatial distribution of population China is changing, the changes of population phenomenon also happens in everyday life.As a Geographical Information System(GIS) subject of workers, We should be more analysis of time and space distribution of population change from the time axis.In order to analyze the temp-spatial distribution characteristics of population and population changes. In this paper, based on the 5 census data( 1935, 1964, 1982, 2000, 2010),county and the municipal administrative division data as data source. on the basis of data analysis,with the method of GIS spatial analysis, quantitative analysis of temp-spatial distribution of population in our country and the population characteristics of temp-spatial changes in 75 years.This paper studies on the temp-spatial distribution of the population is mainly from the following aspects, an index of population spatial expansion intensity(PSEI) were introduced which was calculated by means of the equal-fan ananlysis method in 16 directions, Analysis of each period in our country, the differences of population distribution in different areas,and the major expansion directions were East and Southeast of china. With a population center of gravity model to analyze the integration of time and space distribution of population.According to the geographical proximity will merge adjacent point on the curve of the center of gravity, will our country population density grade of moderate,and summarize our country population distribution area types. The Lorenz curve method was used to analyze the imbalance of population distribution in 1935-2010, the distribution proportion of the population and area is about 20% of the population distribution in 80% of the land area, 80% of the population distribution in 20% of the land area. Statistical population and land area, analysis of population distribution in northwest-southeast Hu Huanyong line for 75 years.The southeast of Hu Huanyong line of the population is dense, but the population proportion in decline.The northwestof Hu Huanyong line of the population issparse,but the population proportion in increase.The average annual growth rate of population, the Hu Huanyong line northwest population with an average annual growth rate higher than the southeastern Hu Huanyong line.This paper studies on population changes mainly from the following aspects, using population center of gravity model to calculate five times the population center of gravity in 1935-2010. And compare the migration ofpopulation center of gravity,it is concluded that population center of gravity has been constantly moving in 1935-2010. The overall characteristics of migration to the southwest, It also shows that the distribution of the population is in constant change.In order to quantitatively analyze the spatial distribution of population is changing. In this paper, by drawing the Lorenz curve of population density, based on the Douglas-Peucker method to depict the 5 population density of the dividing line,realized the quantitative expression of temp-spatial changes of population. Analysis of 5 population density boundary, the temp-spatial distribution of population in 75 years the overall characteristics to the west change in past 75 years,and the change of the county are summarized. The population density of the dividing line is divided into 5 sections,each section of the population density of boundary changes, and summarizes the changes. Changes of the largest province- Ningxia as the research object to select the appropriate temp-spatial changes of population, a detailed analysis of the temp-spatial changes of population in Ningxia province and the causes. The main conclusions of this paper are:(1)The population gravity center model, that 75 years of China’s population distribution has obvious local agglomeration.The population gravity center model, that 75 years of China’s population distribution has obvious local agglomeration. In addition, 75 years of China’s population gravity center is constantly changing, the migration of population gravity center in a certain extent also assisted demonstrates the change of temp-spatial distribution of the population.(2) Lorenz curve, clearly confirmed that the imbalance of population distribution in China. In 75 years, the population distribution is not balanced development of the situation, keep 20% of the population living in 80% of the land area, that is to say 80% of the population living in 20% of the land area.(3)With the extension of city realized the quantitative expression of city population expansion direction, that 75 years China’s population growth direction without regularity,but the downstream area of Yangtze River and in the downstream area of the Yellow River as the largest regional of population expansion in our country.(4)Based on the Lorenz curve, Douglas-Peucker algorithm to achieve the quantitative expression of demographic transition, temp-spatial distribution of population shows the change trend and to the west,and summarized the changes of section and the county. In 75 years, Ningxia Province, as the population of the temp-spatial variation of the largest province. This paper gives a detailed explanation of the causes of population change in Ningxia ’s social and economic development and national policy guidance, etc.