基于地理信息系统技术的学校周边食物环境研究

Study on school surround food environment based on geographic information system technology

目的基于地理信息系统(geographic information systems,GIS)探索学校周边食物环境研究方法,为我国学校周边食物环境评价提供参考依据。方法根据现有研究中食物环境评价指标和高德地图兴趣点(POI)分类编码形成学校周边食物环境评价指标。利用高德地图应用程序接口(API)获取学校周边食物供应环境的POI数据,利用ArcGIS平台转换为食物环境点数据。于2021年11月选取北京市5个区的25个学校进行试用,分析学校周边食物环境状况。采用Stata 13.0进行Kruskal-Wallis秩和检验,采用Dunnett’s t检验进行两两比较。结果将便利店、超市、菜市场、快餐店、中餐厅、外国餐厅和甜品店7个指标作为学校周边食物环境评价指标,以被评价学校为中心构建200、800、1200和1500 m的周边圆形缓冲区。北京市处于中心城区、郊区和远郊区的学校周边800 m范围内的便利店数量中位数分别为19、10和0个,中心城区的便利店数量明显多于远郊区,差异有统计学意义(P<0.05)。在学校周边1500 m范围内,中心城区、郊区和远郊区的快餐店数量中位数分别为128、89和9个,中餐厅数量中位数分别为351、218和51个,外国餐厅数量中位数分别为50、17和0个,甜品店数量中位数分别为18、12和0个,中心城区4类餐饮服务店铺数量均明显多于远郊区,差异均有统计学意义(P<0.05)。结论该研究建立的方法和评价指标可以科学、有效地获取学校周边食物环境信息,并能对不同区域学校周边的食物环境进行定量分析。

Objective To establish the method for evaluating the school surround food environment(SSFE)on geographic information system(GIS)technology,and provide the basis for evaluating the school surround food environment.Methods The SSFE evaluation indicators were formed according to the food outlets described in the published research and the Amap point of interest(POI)classification code,the Application Programming Interface(API)of Amap was used to obtain the POI data in SSFE,which were transfered to the data of food environment points with ArcGIS platform.In November 2021,25 schools from 5 different districts in Beijing were selected as the subjects to analyze the SSFE situation.Kruskal-Wallis rank test was used to analyze the data.Dunnett’s t test was used for pairwise comparison.The used software was Stata 13.0.Results Seven indicators(convenience stores,supermarkets,wet market,fast food restaurants,Chinese restaurants,foreign restaurants and dessert shop)served as the evaluation indicators of SSFE,the circular buffer zones of 200 meters,800 meters,1200 meters and 1500 meters of sampled schools were built.In the buffer zones of 800 meters,the numbers(medians)of convenience stores near schools in central urban,suburban and exurban areas of Beijing were 19,10 and 0,respectively;the number of convenience stores in central urban area was significantly more than that in exurban area(P<0.05);in the buffer zones of 1500 meters,the numbers(medians)of fast food restaurants near schools in central urban,suburban and exurban areas were 128,89 and 9,respectively;the numbers(medians)of Chinese restaurants near schools in central urban,suburban and exurban areas were 351,218 and 51,respectively;the numbers(medians)of foreign restaurants near schools in central urban,suburban and exurban areas were 50,17 and 0,respectively;the numbers(medians)of dessert shops near schools in central urban,suburban and exurban areas were 18,12 and 0,respectively;the number of 4 types of eating and drinking establishments in central urban area was significantly more than that in exurban area(P<0.05).Conclusion The evaluation method and indicators established in present study can obtain the information of SSFE scientifically and efficiently,and can be used to analyze the SSFE evaluation in different areas.