Table_1_Beauty or Blight? Abundant Vegetation in the Presence of Disinvestment Across Residential Parcels and Neighborhoods in Toledo, OH.DOCX

Urban vegetation can generate social and ecological benefits, so vegetation abundance is commonly treated as a proxy for greater benefits. A repeated finding in environmental justice research related to urban vegetation is that commonly marginalized populations live in neighborhoods with less vegetation. However, urban vegetation can function as amenity or disamenity depending on the context and the characteristics of the vegetation. In areas of disinvestment, overgrown vegetation may indicate neglect and lead to negative social outcomes. For example, previous research in the shrinking city of Toledo, Ohio, showed that areas with concentrated residential vacancy and high representation of traditionally marginalized populations also had relatively high vegetation abundance. This can be largely attributed to spontaneous, weedy vegetation in areas of concentrated vacancy. Equal vegetation cover therefore should not necessarily be equated with environmentally just outcomes. Here, we used several high-resolution data sets to study the relationships among vegetation abundance, vegetation quality, and property parcel occupancy on residential land in Toledo. Our results demonstrate that vacant residential land had more abundant vegetation than comparable occupied parcels according to two common metrics (tree canopy cover and the normalized difference vegetation index). Compared to occupied parcels, vacant parcels also had higher rates of blight associated with overgrown vegetation, as recorded during a citywide ground-based survey of property conditions. There were more vacant parcels overall in areas of disinvestment, and on a per-parcel basis, vacant parcels in these high-vacancy areas were also greener relative to nearby occupied parcels than vacant parcels in low-vacancy areas. This indicates that vacant parcels play a disproportionately large role in greening on residential land in areas of disinvestment. These results reinforce the idea that simply quantifying vegetation abundance may be insufficient for understanding urban social-ecological outcomes. Incorporating parcel occupancy data along with multiple strands of information about vegetation type and condition provides context to understand where abundant vegetation functions as amenity vs. disamenity. These perspectives are especially relevant in shrinking cities like Toledo where legacies of urban socioeconomic change have produced widespread areas of disinvestment and land abandonment.

城市植被可产生社会与生态效益，因此植被丰度常被用作衡量效益提升的替代指标。在与城市植被相关的环境正义（environmental justice）研究中，一项反复被证实的结论是：长期处于社会边缘的群体往往居住在植被覆盖较少的社区。然而，城市植被的属性会随情境及植被自身特征的不同，兼具宜人设施（amenity）与不宜人设施（disamenity）的双重功能。在投资匮乏的区域，植被过度生长可能意味着区域疏于管理，进而引发负面社会效应。例如，此前针对美国俄亥俄州托莱多这座收缩型城市（shrinking city）开展的研究显示，住宅空置率集中且传统边缘群体占比偏高的区域，其植被丰度也相对更高。这一现象在很大程度上可归因于空置地块集中区域自发滋生的杂草类植被。因此，单纯的植被覆盖均等未必等同于环境正义的结果。本研究依托多套高分辨率数据集，针对托莱多市住宅用地的植被丰度、植被质量与地块占用率三者间的关联展开分析。研究结果表明，依据两项常用指标——树冠覆盖率（tree canopy cover）与归一化差异植被指数（normalized difference vegetation index）——测算，空置住宅地块的植被丰度均高于可比的已占用地块。通过全市范围的物业状况实地调查记录可知，相较于已占用地块，空置地块因植被过度滋生引发的物业失修破败率也更高。投资匮乏区域的空置地块整体占比更高；按单地块统计，相较于低空置率区域的空置地块，高空置率区域内的空置地块相比周边已占用地块的绿化程度也更高。这意味着在投资匮乏区域，空置地块在住宅用地绿化中发挥了远超其占比的作用。上述研究结果进一步印证了一个观点：仅量化植被丰度或不足以全面理解城市社会生态系统的运行结果。将地块占用数据与植被类型、植被状况的多维度信息相结合，才能为判断植被丰度究竟发挥宜人设施还是不宜人设施的功能提供情境依据。这类研究视角在托莱多这类收缩型城市中尤为关键——这类城市的社会经济变迁遗留问题已导致大范围区域出现投资匮乏与土地弃置现象。