Department of Civil, Environmental and Geomatic Engineering, University College London, London, UK.
School of Civil Engineering, University of Sydney, Sydney, Australia.
J R Soc Interface. 2024 Apr;21(213):20230657. doi: 10.1098/rsif.2023.0657. Epub 2024 Apr 3.
Describing the space-time evolution of urban population is a fundamental challenge in the science of cities, yet a complete theoretical treatment of the underlying dynamics is still missing. Here, we first reconstruct the evolution of London (UK) over 180 years and show that urban growth consists of an initial phase of diffusion-limited growth, followed by the development of the railway transport network and a consequential shift from central to suburban living. Such dynamics-which are analogous to angiogenesis in biological systems-can be described by a minimalist reaction-diffusion model coupled with economic constraints and an adaptive transport network. We then test the generality of our approach by reproducing the evolution of Sydney, Australia, from 1851 to 2011. We show that the rail system coevolves with urban population, displaying hierarchical characteristics that remain constant over time unless large-scale interventions are put in place to alter the modes of transport. These results demonstrate that transport schemes are first-order controls of long-term urbanization patterns and efforts aimed at creating more sustainable and healthier cities require careful consideration of population-transport feedbacks.
描述城市人口的时空演变是城市科学的一个基本挑战，但对于其基础动力学仍然缺乏完整的理论处理。在这里，我们首先重建了伦敦（英国） 180 多年的演变过程，并表明城市增长包括扩散限制增长的初始阶段，随后是铁路运输网络的发展以及由此产生的从市中心到郊区生活的转变。这种类似于生物系统血管生成的动力学可以通过最小化的反应扩散模型来描述，该模型与经济约束和自适应运输网络相结合。然后，我们通过再现澳大利亚悉尼 1851 年至 2011 年的演变，检验了我们方法的通用性。我们表明，铁路系统与城市人口共同进化，表现出层次特征，这些特征在时间上保持不变，除非采取大规模干预措施改变交通方式。这些结果表明，交通方案是长期城市化模式的一级控制，旨在创造更可持续和更健康的城市的努力需要仔细考虑人口-交通反馈。
