A conceptual framework of urban forest ecosystem vulnerability

Abstract

The urban environment is becoming the most common setting in which people worldwide will spend their lives. Urban forests, and the ecosystem services they provide, are becoming a priority for municipalities. Quantifying and communicating the vulnerability of this resource are essential for maintaining a consistent and equitable supply of these ecosystem services. We propose a theory-based conceptual framework for the assessment of urban forest vulnerability that integrates the biophysical, built, and human components of urban forest ecosystems. A review and description of potential vulnerability indicators are provided. Urban forest vulnerability can be defined as the likelihood of decline in ecosystem service supply and its associated benefits for human populations, urban infrastructure, and biodiversity. It is comprised of: 1) exposure, which refers to the stressors and disturbances associated with the urban environment that negatively affect ecosystem function, 2) sensitivity, which is determined by urban forest structure and dictates the system response to forcing from exposures and the magnitude of potential impacts, and 3) adaptive capacity, which is the social and environmental capacity of a system to shift or alter its conditions to reduce its vulnerability or to improve its ability to function while stressed. Potential impacts, or losses in ecosystem service supply, are temporal in nature and require backward-looking monitoring and/or forward-looking modelling to be measured and assessed. Vulnerability can be communicated through the use of indicators, aggregated indices, and mapping. A vulnerability approach can communicate complex issues to decision-makers and advance the theoretical understanding of urban forest ecosystems.

Health impact assessment of Philadelphia's 2025 tree canopy cover goals

“…Cities worldwide are undertaking projects to preserve and increase urban greenspace 1,2 in the face of changing climates, natural disasters, invasive pests, and ongoing development pressures. 3 Researchers and practitioners view urban greening initiatives as providing ecosystem services, supporting sustainability, and promoting liveable cities. [4][5][6] Urban greenspace can be regarded as a preventive public health measure.…”

A spatio-temporal analysis of the relationship between housing renovation, socioeconomic status, and urban forest ecosystems

“…It is also a logical point for the implementation of tree protection measures to mitigate or even avoid tree decline and mortality. Urban trees and forests face a myriad of stressors and disturbances as a result of their location in cities (Steenberg et al., 2017), so municipally mandated tree protection is important, especially on privately owned residential properties where they do not have direct management access.…”

“…However, the urban forest is an exceedingly complex and heterogeneous social–ecological system that presents a wide array of management challenges. Trees and forest stands compete for space with built infrastructure in the densely settled urban landscape and an abundance of social and biophysical stressors continuously threaten tree survival and ecological function (Steenberg et al., 2017; Vogt et al., 2015). Moreover, the urban landscape is dynamic and often rapidly changing.…”

The Legacy of Hurricanes, Historic Land Cover, and Municipal Ordinances on Urban Tree Canopy in Florida (United States)

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