HSD: Collaborative Research: Modeling the Spatial Dynamics and Environmental and Resource Impacts of U.S. Metropolitan Growth and Change

根据美国人口普查局发布的中期预测，从现在到2050年，美国人口可能会增加1.2亿人。在许多方面，了解未来城市增长将在哪里以及如何发生，可能比简单地知道将有多少人寻求居住在美国大都市或其附近更重要。在某种程度上，未来的空间发展模式反映了最近的过去，美国人口的大部分增长将发生在现有大都市区的边缘，其密度大大低于老城市和地区。这种分散的、郊区形式的人口和就业增长将给现有的基础设施系统、自然生态、现有的治理结构和现有的城市社区带来更大的压力，就像过去100年一样。如果人口增长的空间格局反而有利于现有的大都市中心，那么问题将会有所不同，但同样紧迫。尽管受到广泛关注，但城市扩张、邻里变化、资源流失和城市复兴的空间动态和维度，以及这些模式和动态在不同地区和大都市地区之间的差异程度，仍然知之甚少。这个跨学科的研究项目将(1)建立一个综合性的国家空间数据库，用于测量美国大都市人口增长的程度、模式以及对环境和资源的影响；(2)使用该数据库统计识别影响美国所有大陆地区和大都市区都市增长的关键和共同因素；(3)建立一系列基于gis的模型，预测和模拟美国未来人口增长的不同模式和密度；(4)探讨至少三种替代发展情景对自然景观和生态、城市能源和水的使用以及城市空气污染的主要相关因素——车辆行驶里程的影响。该项目旨在加强当代城市分析，从理论上强调交通可达性，并使其能够以理论和经验一致的方式纳入城市发展的其他因素。它还将把城市增长的理论和模型与自然景观变化的测量和分析结合起来，包括资源利用、栖息地丧失和生物多样性等问题。本研究项目的结果将使当代和未来几代城市和环境研究人员以及政策制定者能够确定影响各种城市增长形式的关键因素，并促进旨在保护城市附近土地、水、空气、能源和栖息地资源的规划工作。2005财年美国国家科学基金会人类与社会动力学（HSD）竞赛的一个奖项支持了这个项目。所有NSF理事会和办公室都参与了HSD竞赛和HSD奖项组合的协调管理。

Between now and 2050, the population of the United States likely will grow by 120 million people according to the middle-series projections published by the U.S. Census Bureau. In many ways, knowing where and how future urban growth will occur may be more important than simply knowing how many more people will seek to live in or near the nation's metropolitan areas. To the degree that future spatial development patterns mirror those of the recent past, most of the increase in the U.S. population will occur at the edges of existing metropolitan areas and at densities that are substantially below those of older cities and regions. This decentralized, suburban form of population and job growth will put ever greater pressure on existing infrastructure systems, on the natural ecology, on existing governance structures, and on existing urban communities, just as it has for the last 100 years. Should the spatial pattern of population growth instead favor existing metropolitan centers, the issues will be different though no less pressing. Despite considerable popular attention, the spatial dynamics and dimensions of urban sprawl, neighborhood change, resource loss, and urban revitalization as well as the degree to which such patterns and dynamics vary across different regions and metropolitan areas remain poorly understood. This interdisciplinary research project will (1) build a comprehensive national spatial database for measuring the extent, patterns, and environmental and resource impacts of metropolitan population growth in America; (2) use that database to statistically identify key and common factors that influence metropolitan growth across all continental U.S. regions and metropolitan areas; (3) build a series of GIS-based models for projecting and simulating alternative future patterns and densities of U.S. population growth; and (4) explore the impacts of at least three alternative development scenarios on the natural landscape and ecology, on urban energy and water use, and on vehicle miles of travel, a major correlate of urban air pollution.This project is expected to enhance contemporary urban analysis from its theoretical emphasis on transportation accessibility and allow it to incorporate other factors of urban development in both a theoretically and empirically consistent fashion. It will also integrate theories and models of urban growth with measurements and analysis of natural landscape change, including issues of resource use, habitat loss, and biodiversity. The results of this research project will enable current and future generations of urban and environmental researchers and policy makers to identify key factors that affect a range of forms of metropolitan growth and facilitate planning efforts designed to conserve near-urban land, water, air, energy, and habitat resources. An award resulting from the FY 2005 NSF-wide competition on Human and Social Dynamics (HSD) supports this project. All NSF directorates and offices are involved in the coordinated management of the HSD competition and the portfolio of HSD awards.