城市用地密度分布及其演化：形态模型和过程模型的对比

研究目的：深入分析城市用地密度的空间分布及其演化特征，揭示城市空间结构特征与发展规律。研究方法：圈层分析法，形态模型（ULD）和过程模型（GMP）。研究结果：（1）城市用地密度从城市中心向外逐渐非线性衰减，呈现反S形分布，城市中心吸引和土地资源稀缺性是其形成的主要原因；（2）快速城市化时期城市郊区增长速度快于核心区，导致城市紧凑度下降，突显了合理管控城市边界的重要性；（3）城市紧凑度在城市化过程中表现出先下降后回升趋势，反映了从分散扩张到集中利用的空间模式转变；（4）对于多中心等复杂形态城市，引入新参数可以进一步提升过程模型的拟合优度。研究结论：本文揭示了城市用地密度空间衰减的形态特征和过程机理，形态和过程模型为定量理解城市用地密度空间格局提供了有效工具。

Urban Land Density Distribution and Its Evolution: A Comparative Analysis of Morphology-oriented and Process-oriented Models

The purposes of this study are to analyze the spatial distribution and evolution of urban land density, and to elucidate the dynamics of urban spatial structure and development. The concentric circle analysis method, integrating morphology-oriented (ULD) and process-oriented models (GMP) are used to offer the insights into the changing urban landscape. The research results show that: 1) urban land density prominently displays an inverted S shap distribution, influenced mainly by the tension between central urban attraction and land scarcity. 2) During the period of rapid urbanization, suburban areas expands faster than central areas, resulting in a decline in urban compactness and underscoring the significance of effective boundary control. 3) Urban compactness demonstrates a pattern of initial decrease followed by an increase, mirroring a shift in land use from dispersed to concentrated utilization. 4) For cities with complex urban forms, such as multi-centered cities, introducing new parameters can further improve the goodness of fit of the process-oriented model. In conclusion, this study reveals the morphological characteristics and process mechanisms of the spatial decay of urban land density. Both morphology-oriented and process-oriented models provide effective tools for quantitatively understanding the spatial structural characteristics of urban land density.