Urban sprawl typically consists of low-density urban development dominated by single-family housing and automobile-oriented land use patterns. Sprawl impacts landscape structure and composition, especially along the urban periphery. However, few studies have simultaneously examined sprawl at the building level and by building type (e.g. single family, multi-family) and its relationship to forest landscapes within an urbanizing region. (1) To map and quantify 30-years of sprawl and assess its impacts on forest landscapes in southeast Michigan, a seven-county region centered on the City of Detroit (2) to investigate how different building types, densities, and distances affect forest structure. We used the Random Forests algorithm to analyze high resolution remote-sensing imagery and computed three landscape metrics of forest fragmentation and cohesion, incorporating data on built types and densities. Finally, we investigated the relationship between single-family housing sprawl and forest landscape functionality. The built-up expansion was correlated with an increase in overall tree canopy in the region. However, multilevel analysis revealed these same forest landscapes became less cohesive and more fragmented over time as a result of urban sprawl. Additional correlation tests revealed an increase in patch density and decrease in effective mesh size (meff) and patch cohesion in areas proximate to low-density single-family housing. The analysis documents how urban sprawl negatively impacts forested landscapes. Single-family housing in particular had a detrimental impact on the functionality of adjacent forested landscapes. High thematic resolution enables policy-makers and planners to identify specific policies and interventions to increase landscape functionality.

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城市扩张对密歇根州东南部森林景观的影响，1985-2015

城市蔓延通常包括以单户住宅和以汽车为导向的土地利用模式为主的低密度城市发展。蔓延影响景观结构和构成，尤其是沿城市边缘。然而，很少有研究同时研究建筑层面和建筑类型（例如单户、多户）的蔓延及其与城市化区域内森林景观的关系。(1) 绘制和量化 30 年的蔓延并评估其对密歇根州东南部森林景观的影响，密歇根州东南部是一个以底特律市为中心的七县地区 (2) 调查不同的建筑类型、密度和距离如何影响森林结构体。我们使用随机森林算法来分析高分辨率遥感图像，并计算了森林破碎化和凝聚力的三个景观指标，并结合了建筑类型和密度的数据。最后，我们调查了单户住宅蔓延与森林景观功能之间的关系。建筑的扩张与该地区整体树冠的增加有关。然而，多层次分析表明，由于城市扩张，这些相同的森林景观随着时间的推移变得不那么凝聚力和更加分散。其他相关性测试显示，在靠近低密度单户住宅的区域中，补丁密度增加，有效网格尺寸 (meff) 和补丁凝聚力降低。该分析记录了城市扩张如何对森林景观产生负面影响。单户住宅尤其对相邻森林景观的功能产生不利影响。高主题分辨率使政策制定者和规划者能够确定具体的政策和干预措施，以增加景观功能。