Starting from Jane Jacobs’ critiques and largely promoted and emphasized by New Urbanism, land mixed use (LMU) has become prevalent worldwide. It is believed to be an efficient approach to shaping a higher level of vitality in the economy, equality in society, and quality in the environment. To reveal the differences of this effect at distinct spatial scales, this study selected the two most related outcomes of LMU—resident population distribution and changes—to investigate the LMU impacts. A novel framework is developed to quantify the interactive impact of pairwise LMU-related factors at multiple scales, and the geographical detector is applied to identify the relationship between resident population distribution/changes and LMU. Taking the Jiading District of Shanghai as a pilot case, the framework was applied and tested. The results showed LMU affected resident population distribution distinctively from 600 m to 3000 m grid scales. The grid scale of 1800 m, approximately ten blocks, is revealed to be the optimal scale for discussing LMU with the selected factors. Also, these factors play different roles at different spatial scales. Some factors strongly affect the resident population distribution only when working with other factors. The study emphasized the crucial role of scale in LMU and suggested an open framework to support the decision making and policy making in planning for a better performance of smart growth and sustainability via LMU. It can help researchers obtain the optimal scale for the LMU plans with different sets of factors and identify the key factors in various contexts. Thus, this framework also contributes to supporting other practices of land mixed use beyond our study region.

中文翻译：

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土地混合利用对常住人口的多尺度效应——一种新颖的互动空间因素解释框架

从Jane Jacobs的批评开始，并在新城市主义的大力推动和强调下，土地混合利用（LMU）已经在世界范围内流行起来。它被认为是塑造更高水平的经济活力、社会平等和环境质量的有效途径。为了揭示这种效应在不同空间尺度上的差异，本研究选择了LMU最相关的两个结果——常住人口分布和变化——来调查LMU的影响。开发了一种新颖的框架来量化多个尺度上成对的 LMU 相关因素的交互影响，并应用地理检测器来识别常住人口分布/变化与 LMU 之间的关系。以上海市嘉定区为试点，对该框架进行了应用和测试。结果表明，LMU对600 m至3000 m网格尺度的常住人口分布影响显着。1800 m 的网格规模（大约十个区块）被揭示是讨论 LMU 与所选因素的最佳规模。此外，这些因素在不同的空间尺度上发挥着不同的作用。有些因素只有与其他因素共同作用才能对常住人口分布产生强烈影响。该研究强调了规模在 LMU 中的关键作用，并提出了一个开放的框架来支持决策和政策制定，以通过 LMU 实现更好的智能增长和可持续发展。它可以帮助研究人员获得具有不同因素集的 LMU 计划的最佳规模，并确定不同背景下的关键因素。因此，该框架也有助于支持我们研究区域之外的其他土地混合利用做法。