Discovering Land Of Different Functions Using Crowd Sourcing Geospatial Data

With the acceleration of the global urbanization process,the urban land use has been dysfunction.It directly affects the social development and ecological environmental quality of the city.At the same time,The “National new urbanization development plan(2014-2020)”also clearly pointed out that to optimize the city spatial structure,upgrade the city center functions.Therefore,the classification of urban functional land not only helps to promote and improve the development of existing urban land classification research theory,but also can optimize the urban spatial pattern,improve the functional composition of the central city,promote the rational layout of urban space and comprehensive utilization of development policy to provide support.At present,the domestic and foreign research scholars continue to transform the research perspective and focus on the study of urban land use.The research on the internal spatial structure of the city has also made many achievements,but most of these achievements are obtained from using remote sensing data as the basic data source.There are a number of problems,such as data acquisition is difficult,expensive,low timeliness,classification method complex and low accuracy.The research on the theory of urban land use in China is still not mature,which focuses on the study of urban land use function from the analysis of residents’ travel behavior.Therefore,this paper based on the open and free public source data: geographic data to identify and divide the urban functional land.Based on the data of Beijing OSM road network in 2016,points of interest data in 2017 and basic geographical conditions monitoring data in 2016,Four-ring regional functional land of Beijing was classified.The main contents and results are as follows:(1)This paper presents a method for identifying and dividing urban functional land based on public source geography data.First,the partition of the study area is realized by OSM road network data.Then,based on the definition of urban functional land,the method of urban functional land division is created based on the point of interest.This paper takes Beijing as an example to divide the functional land.The results show that the total accuracy of the research result is 77% and the Kappa coefficient is 0.72.Therefore,this method not only improves the accuracy of urban functional land recognition,but also solves the problem that the existing research data is low in timeliness and difficult to obtain,while avoiding complicated steps using remote sensing data and the trajectory data pedestrians land division function.In addition,this research method can also help urban planners and the public to better understand the complex spatial structure of the city,to provide guidance and reference for the city planning and construction,to provide important decision support for the planning of commercial service facilities,public service facilities,traffic land.(2)The spatial structure of the city a within the four-ring area of Beijing is analyzed.The results show that the urban functional layout in Beijing has the following characteristics: the urban landscape land is mainly in Dongcheng District and Xicheng District.The public management and public service area is mainly in Haidian District,Chaoyang District is mainly based on commercial service land,and the distribution of industrial land in Fengtai District more.In general,the regional function of Beijing four ring is clear,functional layout is more reasonable.At the same time,the paper analyzes the degree of mixed utilization of functional land in the city,and draws the conclusion that the mixed degree of other functions in the city is higher than that of landscape land in Beijing.Some countermeasures and suggestions are put forward for the above research results to provide And to provide decision support and guidance for urban spatial structure adjustment and land space optimization.