多机场体系的概念内涵、识别方法与实证研究

Concept and identification of multiple airport systems:A geographical empirical research

通过对多机场体系概念内涵的解析,基于机场与区域空间关系的视角,构建了多机场体系量化甄别的两步搜索法,并提出了多机场体系界定的关键技术参数。基于机场-都市圈距离模拟优化阈值(70km)识别的全球多机场体系空间格局研究发现:①全球共有59个多机场体系,其业务规模在全球民航运输中占有重要地位;多机场体系内的机场数量多为2个或3个,其中“一主一辅"布局模式占据主导,(航空)港-城的平均车程时间为39.35min。②多机场体系呈现出多核空间布局特征,主要分布在沿海发达地区或大洲/国家尺度的区域性中心;多机场体系的运输规模、机场数量、港-城距离等特征表现出一定的空间异质性。③在空间指向上,多机场体系呈现出中心地指向性和海洋指向性的特征。

Multiple/multi-airport system(MAS),that is,a set of significant airports that serve commercial transport in a metropolitan region regardless of ownership or political control of the individual airports,plays a key role in commercial aviation.According to this definition,there are 3 keywords to describe MAS:1)a set of two or more significant airports,2)that serve commercial traffic,and 3)within a metropolitan region.Therefore,MAS is a typical cross-border(or cross-regional)major infrastructure,which can serve more than one city,namely metropolitan area.However,recent studies'MAS identification method is mainly based on the administrative boundary or the spatial/temporal distance between airports.These methods fail to capture the crossborder characteristic,in addition to the typology of airport and city from a spatial perspective,resulting in the identification bias.After sorting out the concept of MAS,this study proposes a two-step search method to identify MAS.Specifically,the first step is to search for a neighboring primary city with the primary airport as the center,and the second step is to search for significant airports within a specific radius centered on the primary city(i.e.,potential center of metropolitan area)obtained in the previous step.With the help of the Annual World Airport Traffic Dataset 2019 and World Cities Database,this study identified the MAS worldwide in 2018 based on the two-step search method.Then,it analyzed the geography of MAS worldwide and its relationship with the place's attributes through geo-visualizing MAS worldwide.The findings are as follows.First,the two-step search method works well,reflecting the relationship between the airport and the metropolitan area.Second,at the metropolitan scale,the maximum reasonable distance between the airport and the primary city can be 70 km;at the city scale,the ultimate reasonable distance between the airport and the city may be 30 km.Third,59 MAS worldwide in 2018,including 142 civil transport airports,played an essential role in global civil aviation transportation.MAS carries 39.68%of the global throughput,including 3.379 billion passengers and 61 million tons of freight(or air cargo).The average number of airports in the MAS is 2.41.MAS typically contains a large airport with a smaller significant airport.The average airport-city journey time is 39.35 min.Forth,the geography of MAS shows a multicore structure,with most of MAS distributed in coastal areas and regional centers.The detailed characteristics of MAS,such as the transportation volume,the number of airports,and the ground distance between airports and metropolitan area,also shows prominent regional features.Fifth,serval factors,including air transport demand,socio-economic factors,and natural conditions,are jointly related to the geography of MAS.Our findings will pave the way for future research on MAS from a geographic perspective,such as the interaction between MAS and place.