交通方式可达性差距——衡量交通可持续发展的指数

Modal Accessibility Gap: an index of sustainable transportation development

交通因其消耗大量能源而在可持续发展中扮演着重要角色,为了规划交通可持续发展,有必要提出能够评估和衡量交通可持续发展的指数。利用可达性概念和地理信息系统提出交通方式可达性差距指数。该指数由人口数量、就业岗位数、商店数以及学校数等决定,根据公共交通方式和私人交通方式间可达性指数差异计算。就能源效率而言,公共交通方式比私人交通方式更能实现可持续。可达性差距指数越高意味着可持续能力越强。通过比较香港1991年和1996年的可达性差距指数,来检验交通发展的可持续性是否有所提升。最后,讨论了如何运用可达性差距指数来检验土地利用以及交通发展政策和方案,以便确定更可持续的政策和方案。

Consuming a lot of energy, transportation plays an important role in sustainable development. It is necessary to develop indicators for assessing and monitoring sustainable transportation development. The paper proposes an index of modal accessibility gap to measure and monitor sustainable transportation development based on accessibility and geographical information system （GIS）. The modal accessibility gap is calculated by finding the difference between the accessibilities indexes of transit and private cars, which is in turn determined by accessibilities to opportunities such as the number of population, jobs, shops, and schools by transit and private cars. Considering energy-efficiency, transit will achieve sustainable transportation more than private cars. A higher accessibility gap may mean more sustainable development. In the present study, the accessibility gap of Hong Kong in 1991 is compared with that in 1996 to examine whether transportation development has been more sustainable. How to use the index of accessibility gap is also discussed to test land-use and transportation development policies and scenarios to determine the more sustainable ones.