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The Benefits and Limits of Urban Tree Planting for Environmental and Human Health

Pataki, Diane E.; Alberti, Marina; Cadenasso, Mary L.; Felson, Alexander J.; McDonnell, Mark J.; Pincetl, Stephanie; Pouyat, Richard V.; Setala, Heikki; Whitlow, Thomas H. (2021). The Benefits and Limits of Urban Tree Planting for Environmental and Human Health. Frontiers In Ecology And Evolution, 9.

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Abstract

Many of the world's major cities have implemented tree planting programs based on assumed environmental and social benefits of urban forests. Recent studies have increasingly tested these assumptions and provide empirical evidence for the contributions of tree planting programs, as well as their feasibility and limits, for solving or mitigating urban environmental and social issues. We propose that current evidence supports local cooling, stormwater absorption, and health benefits of urban trees for local residents. However, the potential for urban trees to appreciably mitigate greenhouse gas emissions and air pollution over a wide array of sites and environmental conditions is limited. Consequently, urban trees appear to be more promising for climate and pollution adaptation strategies than mitigation strategies. In large part, this is due to space constraints limiting the extent of urban tree canopies relative to the current magnitude of emissions. The most promising environmental and health impacts of urban trees are those that can be realized with well-stewarded tree planting and localized design interventions at site to municipal scales. Tree planting at these scales has documented benefits on local climate and health, which can be maximized through targeted site design followed by monitoring, adaptive management, and studies of long-term eco-evolutionary dynamics.

Keywords

Outdoor Thermal Comfort; Improved Public-health; Carbon Storage; Ecosystem Services; Air-quality; Rainfall Interception; Vegetation; Cover; Design; Impact; Urban Ecology; Forestry; Sustainability; Policy; Climate Mitigation; Climate Adaptation; Ecosystem Disservices

Terrestrial Carbon Stocks across a Gradient of Urbanization: A Study of the Seattle, WA Region

Hutyra, Lucy R.; Yoon, Byungman; Alberti, Marina. (2011). Terrestrial Carbon Stocks across a Gradient of Urbanization: A Study of the Seattle, WA Region. Global Change Biology, 17(2), 783 – 797.

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Abstract

Most of our global population and its CO2 emissions can be attributed to urban areas. The process of urbanization changes terrestrial carbon stocks and fluxes, which, in turn, impact ecosystem functions and atmospheric CO2 concentrations. Using the Seattle, WA, region as a case study, this paper explores the relationships between aboveground carbon stocks and land cover within an urbanizing area. The major objectives were to estimate aboveground live and dead terrestrial carbon stocks across multiple land cover classes and quantify the relationships between urban cover and vegetation across a gradient of urbanization. We established 154 sample plots in the Seattle region to assess carbon stocks as a function of distance from the urban core and land cover [urban (heavy, medium, and low), mixed forest, and conifer forest land covers]. The mean (and 95% CI) aboveground live biomass for the region was 89 +/- 22 Mg C ha-1 with an additional 11.8 +/- 4 Mg C ha-1 of coarse woody debris biomass. The average live biomass stored within forested and urban land covers was 140 +/- 40 and 18 +/- 14 Mg C ha-1, respectively, with a 57% mean vegetated canopy cover regionally. Both the total carbon stocks and mean vegetated canopy cover were surprisingly high, even within the heavily urbanized areas, well exceeding observations within other urbanizing areas and the average US forested carbon stocks. As urban land covers and populations continue to rapidly increase across the globe, these results highlight the importance of considering vegetation in urbanizing areas within the terrestrial carbon cycle.

Keywords

Urbanization & The Environment; Carbon Cycle; Carbon In Soils; Climate Change Prevention; Population & The Environment; Land Cover; Cities & Towns -- Environmental Conditions; Seattle (wash.); Washington (state); Climate Change; Development; Mitigation; Pacific Northwest; Urban; United-states; Woody Debris; Storage; Growth; Responses; Fluxes; Co2; Sequestration; Landscape; Forests

Urban Driven Phenotypic Changes: Empirical Observations and Theoretical Implications for Eco-Evolutionary Feedback

Alberti, Marina; Marzluff, John; Hunt, Victoria M. (2017). Urban Driven Phenotypic Changes: Empirical Observations and Theoretical Implications for Eco-Evolutionary Feedback. Philosophical Transactions Of The Royal Society Of London. Series B, Biological Sciences, 372(1712).

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Abstract

Emerging evidence that cities drive micro-evolution raises the question of whether rapid urbanization of Earth might impact ecosystems by causing systemic changes in functional traits that regulate urban ecosystems' productivity and stability. Intraspecific trait variation-variation in organisms' morphological, physiological or behavioural characteristics stemming from genetic variability and phenotypic plasticity-has significant implications for ecological functions such as nutrient cycling and primary productivity. While it is well established that changes in ecological conditions can drive evolutionary change in species' traits that, in turn, can alter ecosystem function, an understanding of the reciprocal and simultaneous processes associated with such interactions is only beginning to emerge. In urban settings, the potential for rapid trait change may be exacerbated by multiple selection pressures operating simultaneously. This paper reviews evidence on mechanisms linking urban development patterns to rapid phenotypic changes, and differentiates phenotypic changes for which there is evidence of micro-evolution versus phenotypic changes which may represent plasticity. Studying how humans mediate phenotypic trait changes through urbanization could shed light on fundamental concepts in ecological and evolutionary theory. It can also contribute to our understanding of eco-evolutionary feedback and provide insights for maintaining ecosystem function over the long term. This article is part of the themed issue 'Human influences on evolution, and the ecological and societal consequences'.

Keywords

Peromyscus-leucopus Populations; Rapid Evolution; Urbanization; Biodiversity; Adaptation; Dynamics; Birds; Environment; Mechanisms; Morphology; Eco-evolution; Ecosystem Function; Urban Ecology; Ecosystems; Plastic Properties; Urban Environments; Evolution; Phenotypic Plasticity; Feedback; Urban Development; Biological Evolution; Plasticity; Environmental Impact; Nutrient Cycles; Environmental Changes; Productivity; Human Influences; Ecological Effects; Urban Areas; Genetic Variability; Physical Characteristics

Triggering a Climate Change Dominated Anthropocene: Is it Common Among Exocivilizations

Savitch, Ethan; Frank, Adam; Carroll-Nellenback, Jonathan; Haqq-Misra, Jacob; Kleidon, Axel; Alberti, Marina. (2021). Triggering a Climate Change Dominated Anthropocene: Is it Common Among Exocivilizations? Astronomical Journal, 162(5).

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Abstract

We seek to model the coupled evolution of a civilization and its host planet through the era when energy harvesting by the civilization drives the planet into new and adverse climate states. In this way, we ask if triggering Anthropocenes of the kind humanity is experiencing might be a generic feature of planet-civilization evolution. This question has direct consequences for both the study of astrobiology and the sustainability of human civilization. Furthermore, if Anthropocenes prove fatal for some civilizations then they can be considered as one form of a Great Filter and are therefore relevant to discussions of the Fermi Paradox. In this study, we focus on the effects of energy harvesting via combustion and vary the planet's initial chemistry and orbital radius. We find that in this context, the most influential parameter dictating a civilization's fate is their host planet's climate sensitivity, which quantifies how global temperatures change as CO2 is added to the atmosphere. Furthermore, this is in itself a function of the planet's atmospheric CO2 level, so planets with low levels of CO2 will have high climate sensitivities and high probabilities of triggering climate change. Using simulations of the coupled nonlinear model combined with semi-analytic treatments, we find that most planets in our initial parameter space experience diminished growth due to climate effects, an event we call a climate-dominated Anthropocene.

Keywords

Habitable Planets; Complex Life; Evolution; Earth

Carbon Consequences of Land Cover Change and Expansion of Urban Lands: A Case Study in the Seattle Metropolitan Region

Hutyra, Lucy R.; Yoon, Byungman; Hepinstall-Cymerman, Jeffrey; Alberti, Marina. (2011). Carbon Consequences of Land Cover Change and Expansion of Urban Lands: A Case Study in the Seattle Metropolitan Region. Landscape And Urban Planning, 103(1), 83 – 93.

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Abstract

Understanding the role humans play in modifying ecosystems through changing land cover is central to addressing our current and emerging environmental challenges. In particular, the consequences of urban growth and land cover change on terrestrial carbon budgets is a growing issue for our rapidly urbanizing planet. Using the lowland Seattle Statistical Metropolitan Area (MSA) region as a case study, this paper explores the consequences of the past land cover changes on vegetative carbon stocks with a combination of direct field measurements and a time series of remote sensing data. Between 1986 and 2007, the amount of urban land cover within the lowland Seattle MSA more than doubled, from 1316 km(2) to 2798 km(2), respectively. Virtually all of the urban expansion was at the expense of forests with the forested area declining from 4472 km(2) in 1986 to 2878 km(2) in 2007. The annual mean rate of urban land cover expansion was 1 +/- 0.6% year(-1). We estimate that the impact of these regional land cover changes on aboveground carbon stocks was an average loss of 1.2 Mg C ha(-1) yr(-1) in vegetative carbon stocks. These carbon losses from urban expansion correspond to nearly 15% of the lowland regional fossil fuel emissions making it an important, albeit typically overlooked, term in regional carbon emissions budgets. As we plan for future urban growth and strive for more ecologically sustainable cities, it is critical that we understand the past patterns and consequences of urban development to inform future land development and conservation strategies. (C) 2011 Elsevier B.V. All rights reserved.

Keywords

Sprawl; Growth; Carbon Cycle; Emissions; Land Cover; Urbanization; Seattle; Vegetation; Carbon; Carbon Sinks; Case Studies; Cities; Ecosystems; Forests; Fossil Fuels; Humans; Land Use; Planning; Remote Sensing; Time Series Analysis

GPS-Based Exposure to Greenness and Walkability and Accelerometry-Based Physical Activity

James, Peter; Hart, Jaime E.; Hipp, J. Aaron; Mitchell, Jonathan A.; Kerr, Jacqueline; Hurvitz, Philip M.; Glanz, Karen; Laden, Francine. (2017). GPS-Based Exposure to Greenness and Walkability and Accelerometry-Based Physical Activity. Cancer Epidemiology Biomarkers & Prevention, 26(4), 525 – 532.

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Abstract

Background: Physical inactivity is a risk factor for cancer that may be influenced by environmental factors. Indeed, dense and well-connected built environments and environments with natural vegetation may create opportunities for higher routine physical activity. However, studies have focused primarily on residential environments to define exposure and self-reported methods to estimate physical activity. This study explores the momentary association between minute-level global positioning systems (GPS)-based greenness exposure and time-matched objectively measured physical activity. Methods: Adult women were recruited from sites across the United States. Participants wore a GPS device and accelerometer on the hip for 7 days to assess location and physical activity at minutelevel epochs. GPS records were linked to 250mresolution satellitebased vegetation data and Census Block Group-level U.S. Environmental Protection Agency (EPA) Smart Location Database walkability data. Minute-level generalized additive mixed models were conducted to test for associations between GPS measures and accelerometer count data, accounting for repeated measures within participant and allowing for deviations fromlinearity using splines. Results: Among 360 adult women (mean age of 55.3 +/- 10.2 years), we observed positive nonlinear relationships between physical activity and both greenness and walkability. In exploratory analyses, the relationships between environmental factors and physical activity were strongest among those who were white, had higher incomes, and who were middle-aged. Conclusions: Our results indicate that higher levels of physical activity occurred in areas with higher greenness and higher walkability. Impact: Findings suggest that planning and design policies should focus on these environments to optimize opportunities for physical activity. (C) 2017 AACR.

Keywords

Built Environments; Health Research; Breast-cancer; Obesity; Neighborhood; Validation; Validity; Walking; Risk; Energetics

Transitions In Urban Waterfronts: Imagining, Contesting, And Sustaining The Aquatic/terrestrial Interface

Taufen, Anne; Yocom, Ken. (2021). Transitions In Urban Waterfronts: Imagining, Contesting, And Sustaining The Aquatic/terrestrial Interface. Sustainability, 13(1).

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Abstract

Urban waterfronts represent hybrid locations of ecological, economic, and social zones of transition and dispersal, spatially reified between land and water. Yet, through advancements in technology and the emergence of globally linked economies, the structure and function of urban waterfronts as economic and industrial drivers is becoming increasingly complex. As cities seek to redevelop their waterfronts in response to these changes, recent research and scholarship has focused on understanding the ecological, social, and economic benefits derived from urban waterfronts. This research reveals that their benefits are unevenly distributed among local and regional populations as sites of accumulated inequity and inaccessibility that are generative for only a relatively small percentage of the people living in a metropolitan area. Set within this paradoxical nexus, this paper frames a call to scientists, planners, academics, and waterfront activists to expand urban waterfront research from an indicator and benefits model to incorporate three conceptual tools for better understanding key dimensions of waterfront reclamation within the context of green infrastructure research: urban hybridity, functional performance and hierarchies of access. We explore these key dimensions in relation to the waterfront redevelopment of Tacoma, Washington, USA. By acknowledging the hybridity of urban waterfronts, we illustrate that their relative performance and accessibility require ongoing empirical study and practical intervention. Our theoretical explorations plot some of the potential areas of investigation for examining the structural and functional transitions of urban waterfronts as critical locations for green infrastructure development for the 21st century.

Keywords

Place Attachment; Community Participation; Cities; Justice; Indicators; Challenges; Resilience; Governance; Space; Urban Waterfronts; Complexity; Urban Hybridity; Functional Performance; Hierarchies Of Access; Public Access; Stormwater Management; Infrastructure; Reclamation; Green Aspects; Waterfront Development; Urban Areas; Terrestrial Environments; Waterfronts; Economics; Hierarchies; Redevelopment; Regulation; Dispersal; Economic Activity; Shorelines; Regions; Terrestrial Ecosystems; Sustainable Development; Structure-function Relationships; Ports; Rivers; Metropolitan Areas; Urbanization; United States--us

Protecting the Idyll but Not the Environment: Second Homes, Amenity Migration and Rural Exclusion in Washington State

Kondo, Michelle C.; Rivera, Rebeca; Rullman, Stan, Jr. (2012). Protecting the Idyll but Not the Environment: Second Homes, Amenity Migration and Rural Exclusion in Washington State. Landscape And Urban Planning, 106(2), 174 – 182.

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Abstract

Researchers are beginning to take notice of amenity migration processes and their impacts in exurban areas of the U.S. Our research explores second-home owners as contributors to processes of amenity migration. Using a mixed-method approach combining spatial data and interview analyses, we investigate both the structural and behavioral aspects of amenity migration in San Juan and Okanogan counties of Washington State. Results indicate that second-home owners' desire for privacy and escape is reflected in patterns of spatial isolation among second homes in the study area. These patterns have potentially significant ecological effects. Second-home owners also seek to protect their investments by supporting regulations which support their version of a rural idyll. Therefore, policy-makers should be wary of strategies to promote regulations which promote aesthetic rather than social and ecological function. (C) 2012 Elsevier B.V. All rights reserved.

Keywords

Land-use; Colorado Mountains; Political Ecology; Landscape Change; United-states; Gentrification; Residents; Attitudes; Growth; West; Amenity Migration; Second Homes; Mixed-method Research

Planning For The Future Of Urban Biodiversity: A Global Review Of City-scale Initiatives.

Nilon, Charles H.; Aronson, Myla F. J.; Cilliers, Sarel S.; Dobbs, Cynnamon; Frazee, Lauren J.; Goddard, Mark A.; O’Neill, Karen M.; Roberts, Debra; Stander, Emilie K.; Werner, Peter; Winter, Marten; Yocom, Ken P. (2017). Planning For The Future Of Urban Biodiversity: A Global Review Of City-scale Initiatives. Bioscience, 67(4), 331 – 341.

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Abstract

Cities represent considerable opportunities for forwarding global biodiversity and sustainability goals. We developed key attributes for conserving biodiversity and for ecosystem services that should be included in urban-planning documents and reviewed 135 plans from 40 cities globally. The most common attributes in city plans were goals for habitat conservation, air and water quality, cultural ecosystem services, and ecological connectivity. Few plans included quantitative targets. This lack of measurable targets may render plans unsuccessful for an actionable approach to local biodiversity conservation. Although most cities include both biodiversity and ecosystem services, each city tends to focus on one or the other. Comprehensive planning for biodiversity should include the full range of attributes identified, but few cities do this, and the majority that do are mandated by local, regional, or federal governments to plan specifically for biodiversity conservation. This research provides planning recommendations for protecting urban biodiversity based on ecological knowledge.

Keywords

Sustainability; Urban Planning; Urban Biodiversity; Urban Ecology (biology); Water Quality; Air Quality; Biodiversity Conservation; Ecosystem Services; Governance; Policy Regulation; Green Infrastructure; Climate-change; Human Health; Cities; Opportunities; Metaanalysis; Framework; Richness

Coping on the Inside: Design for Therapeutic Incarceration Interventions – A Case Study

Wagenfeld, Amy; Winterbottom, Daniel. (2021). Coping on the Inside: Design for Therapeutic Incarceration Interventions – A Case Study. Work-a Journal Of Prevention Assessment & Rehabilitation, 68(1), 97 – 106.

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Abstract

BACKGROUND: Adjusting to incarceration is traumatic. An under-utilized strategy understood to buffer and counteract the negative impacts of incarceration are nature interventions. OBJECTIVE: Outcomes of an interdisciplinary design studio course focused on developing masterplans for a women's prison in the Pacific Northwest (US) are presented. Course objectives included comprehension and application of therapeutic and culturally expressive design principles to increase the benefits of environmental design within a carceral setting; collaboration, developing a deeper, more representative understanding of how design processes can improve the lives of marginalized populations; and enhancing design skills, including at masterplan and schematic scale using an iterative process and reflection. METHODS: A landscape architect, occupational therapist, and architect teaching team, with support from architects and justice specialists facilitated an elective design studio course to redesign the Washington Corrections Center for Women campus. RESULTS: In a ten-week academic quarter, six student design teams created conceptual masterplans for therapeutic outdoor spaces at the Washington Corrections Center for Women. Students presented their plans to prison staff, current and ex-offenders, and architects and landscape architects in practice, and then received positive feedback. CONCLUSION: Despite well-documented need for and value of nature interventions to improve health and wellbeing for everyone regardless of circumstance or situation, the project awaits administrative approval to move forward to installation.

Keywords

Recovery; Exposure; Health; Correctional Institutions; Environmental Justice; Therapeutic Outdoor Environments; Interdisciplinary Academic Design Studio