Research On Land Use Optimization Around Transit Station Based On High Resolution Satellite Image

With the rapid development of cities and transportation infrastructure,problems such as shortage of land resource and low efficiency of land use have emerge and grown increasingly serious.As the backbone of transportation infrastructure,rail transit system plays a significant role in coordination between transportation infrastructure and land use,and addressing urban development problems.In this paper,experiment of land use information extraction was performed based on high resolution satellite image and detailed study was carried out on current situation of land use around one urban transit station.Major work are as follows:(1)Method for the extraction of floor area ratio of the classified buildings was proposed and was applied on a WorldView-3 satellite image.First,principal component transformation and multi-classification-level multiresolution segmentation using weighted mean square method were performed successively.Next,based on features,which are the first principal component,the second principal component,length to width ratio,main direction,border index and rectangular fit,object samples were selected according to stratified proportional sampling and systematic sampling and then were put into the training of Naive Bayesian Network classifier.Finally,trained classifier was used to extract the floor area ratio of residential,business and commercial,and industrial types of buildings.Results showed that the average accuracy for shadow area method is 93.90%and 85.19%for shadow length method and shadow area method is more effective than shadow length method.Meanwhile,the proposed method for the extraction of floor area ratio of the classified buildings was validated.(2)Case study was taken on subway station Changyang.First,passenger travel surveys were done in subway station Changyang and its neighboring stations.Next,on the foundation of survey data,three reasonable catchments of walking,cycling and bus were calculated and discounted according to road network around the station,and then the potential catchment under the Voronoi diagram was settled.Finally,current situations of land use layout,building density and floor area ratio in the regions along the line and perpendicular to the line of core catchment(R=300m),direct catchment(R=742m)and secondary catchment(R=1000m)were analyzed respectively.Results indicated two conclusions:1)Usually the shape of rail transit station is irregular;2)The classification of Changyang station does not coincide with commercial service type.Its land use layout does not reach the ideal layout.Unbalanced land use development of different degree exists in various regions.(3)Multi-object optimization model for land use was established under the core concept of Transit Oriented Development.By optimization toolbox of MATLAB,the optimization model was applied in three catchments.Results suggested that there is large room for the improvement of land use in all catchments of Changyang station.It is recommended that unused land should be made the most to develop into environmental quality and commercial service related land use types so that the regional development of Changyang can be in line with the development planning.