Lens Michael C, Monkkonen Paavo
Assistant professor of urban planning in the University of California, Los Angeles (UCLA) Luskin School of Public Affairs.
Assistant professor of urban planning in the UCLA Luskin School of Public Affairs.
J Am Plann Assoc. 2016;82(1):6-21. doi: 10.1080/01944363.2015.1111163. Epub 2015 Dec 28.
Income segregation has risen in each of the last four decades in U.S. metropolitan areas, which can have lifelong impacts on the health, economic productivity, and behaviors of residents. Although it is widely assumed that local land use regulations-such as minimum lot sizes and growth controls-exclude low-income households from wealthier neighborhoods, the empirical research is surprisingly limited. We examine the relationship between land use regulation and segregation by income using new measures for the 95 biggest cities in the United States. We find that density restrictions are associated with the segregation of the wealthy and middle income, but not the poor. We also find that more local pressure to regulate land use is linked to higher rates of income segregation, but that more state control is connected to lower-income segregation.
Density restrictions do drive urban income segregation of the rich, not the poor, but should be addressed because rich enclaves create significant metropolitan problems. Planners at the local level need assistance from regional and state efforts to ameliorate income segregation. Inclusionary housing requirements have a greater potential to reduce income segregation than bringing higher-income households into lower-income parts of the city. Finally, comprehensive and consistent data on the impacts of local land use regulations should be collected to inform future research and planning practice.
问题、研究策略与发现:在美国大都市区,收入隔离在过去四十年中的每十年都有所上升,这可能会对居民的健康、经济生产力和行为产生终身影响。尽管人们普遍认为,诸如最小地块面积和增长控制等地方土地使用法规会将低收入家庭排除在较富裕社区之外,但实证研究却出奇地有限。我们使用针对美国95个最大城市的新指标,研究土地使用法规与收入隔离之间的关系。我们发现,密度限制与富人和中等收入人群的隔离有关,但与穷人无关。我们还发现,更多的地方土地使用监管压力与更高的收入隔离率相关,但更多的州控制则与更低的收入隔离相关。
密度限制确实会导致城市中富人与穷人的收入隔离,而非穷人间的隔离,但这一问题仍需解决,因为富人聚居区会引发严重的大都市问题。地方层面的规划者需要区域和州层面的努力来改善收入隔离。包容性住房要求在减少收入隔离方面比将高收入家庭引入城市低收入地区更具潜力。最后,应收集有关地方土地使用法规影响的全面且一致的数据,为未来的研究和规划实践提供参考。