Context Urbanization is the most important form of landscape change and is increasingly affecting biodiversity and ecosystem functions. Understanding how landscape patterns change in space and time is central to the evaluation of the environmental impacts of urbanization. Objectives This research explores the spatiotemporal patterns of land use change in the Swiss urban agglomerations of Bern, Lausanne and Zurich at two characteristic spatial extents, and compares them to prominent hypotheses of urbanization patterns. Methods For each urban agglomeration, four temporal snapshots from 1980 to 2016 have been derived from the land use inventory of the Swiss Federal Statistical Office. Fractal analysis of the area–radius relationship of urban land is used to separate each agglomeration into two characteristic spatial extents according to the distance of the city center, namely the inner and outer zones. The landscape metrics and growth modes are then computed at such extents. Results The time series of landscape metrics and growth modes reveal fairly different patterns when computed in the inner and outer zones respectively. Bern and Lausanne exhibit mostly traits of coalescence stages at the inner zone while displaying many characteristics of diffusion in the outer zone. In contrast, the trends of observed in the inner and outer zones of Zurich are both reminiscent of a coalescence stages. Conclusions Fractal analysis can be a useful approach to detect characteristic extents of urban agglomerations at which distinct spatiotemporal patterns might be observed. Current models of urbanization patterns should incorporate the notion of characteristic extents more explicitly.

中文翻译：

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瑞士三个城市群城市化的时空模式：来自景观指标、增长模式和分形分析的见解

背景 城市化是景观变化的最重要形式，对生物多样性和生态系统功能的影响越来越大。了解景观模式如何在空间和时间上变化是评估城市化对环境影响的核心。目标 本研究探讨了瑞士城市群伯尔尼、洛桑和苏黎世在两个特征空间范围内土地利用变化的时空模式，并将它们与城市化模式的突出假设进行了比较。方法对于每个城市群，从瑞士联邦统计局的土地利用清单中导出了 1980 年至 2016 年的四个时间快照。利用城市用地面积-半径关系的分形分析，将每个城市群按照城市中心的距离划分为两个特征空间范围，即内带和外带。然后在这样的范围内计算景观指标和增长模式。结果 当分别在内部和外部区域计算时，景观指标和增长模式的时间序列显示出相当不同的模式。伯尔尼和洛桑在内带主要表现出聚结阶段的特征，而在外带则表现出许多扩散特征。相比之下，在苏黎世内外带观察到的趋势都让人联想到聚结阶段。结论 分形分析可以作为一种有用的方法来检测城市群的特征范围，在这些范围内可以观察到不同的时空模式。当前的城市化模式模型应更明确地纳入特征范围的概念。