Environmental and biological controls of urban tree transpiration in the Upper Midwest

Science.gov (United States)

Peters, E. B.; McFadden, J.; Montgomery, R.

2009-12-01

Urban trees provide a variety of ecosystem services to urban and suburban areas, including carbon uptake, climate amelioration, energy reduction, and stormwater management. Tree transpiration, in particular, modifies urban water budgets by providing an alternative pathway for water after rain events. The relative importance of environmental and biological controls on transpiration are poorly understood in urban areas, yet these controls are important for quantifying and scaling up the ecosystem services that urban trees provide at landscape and regional scales and predicting how urban ecosystems will respond to climate changes. The objectives of our study were to quantify the annual cycle of tree transpiration in an urban ecosystem and to determine how different urban tree species and plant functional types respond to environmental drivers. We continuously measured whole-tree transpiration using thermal dissipation sap flow at four urban forest stands that were broadly representative of the species composition and tree sizes found in a suburban residential neighborhood of Minneapolis-Saint Paul, Minnesota. A total of 40 trees, representing different species, plant functional types, successional stages, and xylem anatomy, were sampled throughout the 2007 and 2008 growing seasons (April-November). At each site we monitored soil moisture, air temperature, and relative humidity continuously, and we measured leaf area index weekly. Urban tree transpiration was strongly correlated with diurnal changes in vapor pressure deficit and photosynthetically active radiation and with seasonal changes in leaf area index. We found that plant functional type better explained species differences in transpiration per canopy area than either successional stage or xylem anatomy, largely due to differences in canopy structure between conifer and broad-leaf deciduous trees. We also observed inter-annual differences in transpiration rates due to a mid-season drought and longer growing

Urban warming drives insect pest abundance on street trees.

Directory of Open Access Journals (Sweden)

Emily K Meineke

Full Text Available Cities profoundly alter biological communities, favoring some species over others, though the mechanisms that govern these changes are largely unknown. Herbivorous arthropod pests are often more abundant in urban than in rural areas, and urban outbreaks have been attributed to reduced control by predators and parasitoids and to increased susceptibility of stressed urban plants. These hypotheses, however, leave many outbreaks unexplained and fail to predict variation in pest abundance within cities. Here we show that the abundance of a common insect pest is positively related to temperature even when controlling for other habitat characteristics. The scale insect Parthenolecanium quercifex was 13 times more abundant on willow oak trees in the hottest parts of Raleigh, NC, in the southeastern United States, than in cooler areas, though parasitism rates were similar. We further separated the effects of heat from those of natural enemies and plant quality in a greenhouse reciprocal transplant experiment. P. quercifex collected from hot urban trees became more abundant in hot greenhouses than in cool greenhouses, whereas the abundance of P. quercifex collected from cooler urban trees remained low in hot and cool greenhouses. Parthenolecanium quercifex living in urban hot spots succeed with warming, and they do so because some demes have either acclimatized or adapted to high temperatures. Our results provide the first evidence that heat can be a key driver of insect pest outbreaks on urban trees. Since urban warming is similar in magnitude to global warming predicted in the next 50 years, pest abundance on city trees may foreshadow widespread outbreaks as natural forests also grow warmer.

Urban tree species show the same hydraulic response to vapor pressure deficit across varying tree size and environmental conditions.

Directory of Open Access Journals (Sweden)

Lixin Chen

Full Text Available The functional convergence of tree transpiration has rarely been tested for tree species growing under urban conditions even though it is of significance to elucidate the relationship between functional convergence and species differences of urban trees for establishing sustainable urban forests in the context of forest water relations.We measured sap flux of four urban tree species including Cedrus deodara, Zelkova schneideriana, Euonymus bungeanus and Metasequoia glyptostroboides in an urban park by using thermal dissipation probes (TDP. The concurrent microclimate conditions and soil moisture content were also measured. Our objectives were to examine 1 the influence of tree species and size on transpiration, and 2 the hydraulic control of urban trees under different environmental conditions over the transpiration in response to VPD as represented by canopy conductance. The results showed that the functional convergence between tree diameter at breast height (DBH and tree canopy transpiration amount (E(c was not reliable to predict stand transpiration and there were species differences within same DBH class. Species differed in transpiration patterns to seasonal weather progression and soil water stress as a result of varied sensitivity to water availability. Species differences were also found in their potential maximum transpiration rate and reaction to light. However, a same theoretical hydraulic relationship between G(c at VPD = 1 kPa (G(cref and the G(c sensitivity to VPD (-dG(c/dlnVPD across studied species as well as under contrasting soil water and R(s conditions in the urban area.We concluded that urban trees show the same hydraulic regulation over response to VPD across varying tree size and environmental conditions and thus tree transpiration could be predicted with appropriate assessment of G(cref.

Urban tree species show the same hydraulic response to vapor pressure deficit across varying tree size and environmental conditions.

Science.gov (United States)

Chen, Lixin; Zhang, Zhiqiang; Ewers, Brent E

2012-01-01

The functional convergence of tree transpiration has rarely been tested for tree species growing under urban conditions even though it is of significance to elucidate the relationship between functional convergence and species differences of urban trees for establishing sustainable urban forests in the context of forest water relations. We measured sap flux of four urban tree species including Cedrus deodara, Zelkova schneideriana, Euonymus bungeanus and Metasequoia glyptostroboides in an urban park by using thermal dissipation probes (TDP). The concurrent microclimate conditions and soil moisture content were also measured. Our objectives were to examine 1) the influence of tree species and size on transpiration, and 2) the hydraulic control of urban trees under different environmental conditions over the transpiration in response to VPD as represented by canopy conductance. The results showed that the functional convergence between tree diameter at breast height (DBH) and tree canopy transpiration amount (E(c)) was not reliable to predict stand transpiration and there were species differences within same DBH class. Species differed in transpiration patterns to seasonal weather progression and soil water stress as a result of varied sensitivity to water availability. Species differences were also found in their potential maximum transpiration rate and reaction to light. However, a same theoretical hydraulic relationship between G(c) at VPD = 1 kPa (G(cref)) and the G(c) sensitivity to VPD (-dG(c)/dlnVPD) across studied species as well as under contrasting soil water and R(s) conditions in the urban area. We concluded that urban trees show the same hydraulic regulation over response to VPD across varying tree size and environmental conditions and thus tree transpiration could be predicted with appropriate assessment of G(cref).

Urban forest biomass estimates: is it important to use allometric relationships developed specifically for urban trees? 

Science.gov (United States)

M.R. McHale; I.C. Burke; M.A. Lefsky; P.J. Peper; E.G. McPherson

2009-01-01

Many studies have analyzed the benefits, costs, and carbon storage capacity associated with urban trees. These studies have been limited by a lack of research on urban tree biomass, such that estimates of carbon storage in urban systems have relied upon allometric relationships developed in traditional forests. As urbanization increases globally, it is becoming...

Growing quality of life: urban trees, birth weight, and crime

Science.gov (United States)

John Kirkland; Geoffrey Donovan

2011-01-01

City dwellers can find many reasons to value neighborhood trees. The urban greenery provides relief from the built environment that many find appealing. In fact, a previous study found that a tree in front of a home increased that home's sales price by more than $7,000. Two new studies explore the measurable effects that urban trees and green spaces have a human...

Roles of Urban Tree Canopy and Buildings in Urban Heat Island Effects: Parameterization and Preliminary Results

Science.gov (United States)

Loughner, Christopher P.; Allen, Dale J.; Zhang, Da-Lin; Pickering, Kenneth E.; Dickerson, Russell R.; Landry, Laura

2012-01-01

Urban heat island (UHI) effects can strengthen heat waves and air pollution episodes. In this study, the dampening impact of urban trees on the UHI during an extreme heat wave in the Washington, D.C., and Baltimore, Maryland, metropolitan area is examined by incorporating trees, soil, and grass into the coupled Weather Research and Forecasting model and an urban canopy model (WRF-UCM). By parameterizing the effects of these natural surfaces alongside roadways and buildings, the modified WRF-UCM is used to investigate how urban trees, soil, and grass dampen the UHI. The modified model was run with 50% tree cover over urban roads and a 10% decrease in the width of urban streets to make space for soil and grass alongside the roads and buildings. Results show that, averaged over all urban areas, the added vegetation decreases surface air temperature in urban street canyons by 4.1 K and road-surface and building-wall temperatures by 15.4 and 8.9 K, respectively, as a result of tree shading and evapotranspiration. These temperature changes propagate downwind and alter the temperature gradient associated with the Chesapeake Bay breeze and, therefore, alter the strength of the bay breeze. The impact of building height on the UHI shows that decreasing commercial building heights by 8 m and residential building heights by 2.5 m results in up to 0.4-K higher daytime surface and near-surface air temperatures because of less building shading and up to 1.2-K lower nighttime temperatures because of less longwave radiative trapping in urban street canyons.

Biophysical control of whole tree transpiration under an urban environment in Northern China

Science.gov (United States)

Lixin Chen; Zhiqiang Zhang; Zhandong Li; Jianwu Tang; Peter Caldwell; et al

2011-01-01

Urban reforestation in China has led to increasing debate about the impact of urban trees and forests on water resources. Although transpiration is the largest water flux leaving terrestrial ecosystems, little is known regarding whole tree transpiration in urban environments. In this study, we quantified urban tree transpiration at various temporal scales and examined...

Water, heat, and airborne pollutants effects on transpiration of urban trees

International Nuclear Information System (INIS)

Wang Hua; Ouyang Zhiyun; Chen Weiping; Wang Xiaoke; Zheng Hua; Ren Yufen

2011-01-01

Transpiration rates of six urban tree species in Beijing evaluated by thermal dissipation method for one year were correlated to environmental variables in heat, water, and pollutant groups. To sort out colinearity of the explanatory variables, their individual and joint contributions to variance of tree transpiration were determined by the variation and hierarchical partitioning methods. Majority of the variance in transpiration rates was associated with joint effects of variables in heat and water groups and variance due to individual effects of explanatory group were in comparison small. Atmospheric pollutants exerted only minor effects on tree transpiration. Daily transpiration rate was most affected by air temperature, soil temperature, total radiation, vapor pressure deficit, and ozone. Relative humidity would replace soil temperature when factors influencing hourly transpiration rate was considered. - Highlights: → Heat, water, pollutants effect on transpiration was evaluated by partitioning method. → Urban tree transpiration was mainly affected by combined effects of these variables. → The heat and water variables affected transpiration of urban trees. → The urban air pollution merely acts as an antagonistic factor. - Heat and water related environmental variables affected transpiration of urban trees and ozone was an added yet minor stress factor.

Declining urban and community tree cover in the United States

Science.gov (United States)

David J. Nowak; Eric J. Greenfield

2018-01-01

Paired aerial photographs were interpreted to assess recent changes (c. 2009–2014) in tree, impervious and other cover types within urban/community and urban land in all 50 United States and the District of Columbia. National results indicate that tree cover in urban/community areas of the United States is on the decline at a rate of about 175,000 acres per year, which...

Functional traits of urban trees: Air pollution mitigation potential

DEFF Research Database (Denmark)

Grote, Rüdiger; Samson, Roeland; Alonso, Rocío

2016-01-01

In an increasingly urbanized world, air pollution mitigation is considered one of most important issues in city planning. Urban trees help to improve air quality by facilitating widespread deposition of various gases and particles through the provision of large surface areas as well as through...... are manifested depends on species-specific tree properties: that is, their "traits". We summarize and discuss the current knowledge on how such traits affect urban air pollution. We also present aggregated traits of some of the most common tree species in Europe, which can be used as a decision-support tool...... their influence on microclimate and air turbulence. However, many of these trees produce wind-dispersed pollen (a known allergen) and emit a range of gaseous substances that take part in photochemical reactions - all of which can negatively affect air quality. The degree to which these air-quality impacts...

Carbon storage and sequestration by trees in urban and community areas of the United States

International Nuclear Information System (INIS)

Nowak, David J.; Greenfield, Eric J.; Hoehn, Robert E.; Lapoint, Elizabeth

2013-01-01

Carbon storage and sequestration by urban trees in the United States was quantified to assess the magnitude and role of urban forests in relation to climate change. Urban tree field data from 28 cities and 6 states were used to determine the average carbon density per unit of tree cover. These data were applied to statewide urban tree cover measurements to determine total urban forest carbon storage and annual sequestration by state and nationally. Urban whole tree carbon storage densities average 7.69 kg C m −2 of tree cover and sequestration densities average 0.28 kg C m −2 of tree cover per year. Total tree carbon storage in U.S. urban areas (c. 2005) is estimated at 643 million tonnes ($50.5 billion value; 95% CI = 597 million and 690 million tonnes) and annual sequestration is estimated at 25.6 million tonnes ($2.0 billion value; 95% CI = 23.7 million to 27.4 million tonnes). -- Highlights: •Total tree carbon storage in U.S. urban areas (c. 2005) is estimated at 643 million tonnes. •Total tree carbon storage in U.S. urban and community areas is estimated at 1.36 billion tonnes. •Net carbon sequestration in U.S. urban areas varies by state and is estimated at 18.9 million tonnes per year. •Overlap between U.S. forest and urban forest carbon estimates is between 247 million and 303 million tonnes. -- Field and tree cover measurements reveal carbon storage and sequestration by trees in U.S. urban and community areas

Urban Crowns: crown analysis software to assist in quantifying urban tree benefits

Science.gov (United States)

Matthew F. Winn; Sang-Mook Lee Bradley; Philip A. Araman

2010-01-01

UrbanCrowns is a Microsoft® Windows®-based computer program developed by the U.S. Forest Service Southern Research Station. The software assists urban forestry professionals, arborists, and community volunteers in assessing and monitoring the crown characteristics of urban trees (both deciduous and coniferous) using a single side-view digital photograph. Program output...

Carbon Sequestration by Urban Trees

DEFF Research Database (Denmark)

Fares, Silvano; Paoletti, Elena; Calfapietra, Carlo

2017-01-01

Carbon dioxide (CO2) is the most prominent component of anthropogenic greenhouse gas emissions, resulting mainly from fuel combustion in the built environment – for activities such as heating of buildings, urban mobility and cooking. The concentration of near-surface CO2 in cities is affected by ....... In this chapter, we review the most recent studies and highlight emerging research needs for a better understanding of present and future roles of urban trees in removing CO2 from the atmosphere....

Sustaining America's urban trees and forests: a Forests on the Edge report

Science.gov (United States)

David J. Nowak; Paula B. Randler; Eric J. Greenfield; Sara J. Comas; Mary A. Carr; Ralph J. Alig

2010-01-01

Close to 80 percent of the U.S. population lives in urban areas and depends on the essential ecological, economic, and social benefits provided by urban trees and forests. However, the distribution of urban tree cover and the benefits of urban forests vary across the United States, as do the challenges of sustaining this important resource. As urban areas expand...

Assessment of ecosystem services provided by urban trees: public lands within the Urban Growth Boundary of Corvallis, OR

Science.gov (United States)

Public lands within the Urban Growth Boundary of Corvallis, Oregon contain a diverse population of about 440,000 trees that include over 300 varieties and have an estimated tree cover of 31%. While often unrecognized, urban trees provide a variety of “ecosystem services” or dire...

A modeling study of the impact of urban trees on ozone

Science.gov (United States)

David J. Nowak; Kevin L. Civerolo; S. Trivikrama Rao; Gopal Sistla; Christopher J. Luley; Daniel E. Crane

2000-01-01

Modeling the effects of increased urban tree cover on ozone concentrations (July 13-15, 1995) from Washington, DC, to central Massachusetts reveals that urban trees generally reduce ozone concentrations in cities, but tend to increase average ozone concentrations in the overall modeling domain. During the daytime, average ozone reductions in urban areas (1 ppb) were...

Modeling the Ecosystem Services Provided by Trees in Urban Ecosystems: Using Biome-BGC to Improve i-Tree Eco

Science.gov (United States)

Brown, Molly E.; McGroddy, Megan; Spence, Caitlin; Flake, Leah; Sarfraz, Amna; Nowak, David J.; Milesi, Cristina

2012-01-01

As the world becomes increasingly urban, the need to quantify the effect of trees in urban environments on energy usage, air pollution, local climate and nutrient run-off has increased. By identifying, quantifying and valuing the ecological activity that provides services in urban areas, stronger policies and improved quality of life for urban residents can be obtained. Here we focus on two radically different models that can be used to characterize urban forests. The i-Tree Eco model (formerly UFORE model) quantifies ecosystem services (e.g., air pollution removal, carbon storage) and values derived from urban trees based on field measurements of trees and local ancillary data sets. Biome-BGC (Biome BioGeoChemistry) is used to simulate the fluxes and storage of carbon, water, and nitrogen in natural environments. This paper compares i-Tree Eco's methods to those of Biome-BGC, which estimates the fluxes and storage of energy, carbon, water and nitrogen for vegetation and soil components of the ecosystem. We describe the two models and their differences in the way they calculate similar properties, with a focus on carbon and nitrogen. Finally, we discuss the implications of further integration of these two communities for land managers such as those in Maryland.

Vulnerability Analysis of Urban Drainage Systems: Tree vs. Loop Networks

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Chi Zhang

2017-03-01

Full Text Available Vulnerability analysis of urban drainage networks plays an important role in urban flood management. This study analyzes and compares the vulnerability of tree and loop systems under various rainfall events to structural failure represented by pipe blockage. Different pipe blockage scenarios, in which one of the pipes in an urban drainage network is assumed to be blocked individually, are constructed and their impacts on the network are simulated under different storm events. Furthermore, a vulnerability index is defined to measure the vulnerability of the drainage systems before and after the implementation of adaptation measures. The results obtained indicate that the tree systems have a relatively larger proportion of critical hydraulic pipes than the loop systems, thus the vulnerability of tree systems is substantially greater than that of the loop systems. Furthermore, the vulnerability index of tree systems is reduced after they are converted into a loop system with the implementation of adaptation measures. This paper provides an insight into the differences in the vulnerability of tree and loop systems, and provides more evidence for development of adaptation measures (e.g., tanks to reduce urban flooding.

Economic Valuation of Urban Trees: Ribnjak Park Case Study, Zagreb

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Karlo Beljan

2015-06-01

Full Text Available Background and Purpose: Population growth, urbanisation and technological development are creating a growing need for urban forests and parks, which are becoming green oases for recreation and relaxation. Apart from the sociological and economic components, urban forest valuation is presented through tourism, the market value of main and secondary forest products, and the growing value of real estate in the vicinity of green areas. Environmental economics explores the optimal ratio between the costs and the benefits received from the investment in the environment. The aim of this research is monetary valuation of urban trees. Materials and Methods: A Danish model for tree value determination was applied in Ribnjak Park as a case study. The model is based on tree growing costs and the present value. It is limited by the subjective aesthetic tree value estimation, but it is used in Europe because of its practicality. Individual tree value estimation is used because of the tree damage from vehicles or new residential buildings. The method is suitable for individual trees or groups of trees, but it is not appropriate for forest stands. Twenty random selected trees from nine different tree species have been analysed in the park. Diameter at breast height, tree height, expected age, aesthetic value and location were recorded for each tree. Furthermore, ecological, social and health tree values were taken into account separately with the calculation of points. Results: According to the evaluation, the average monetary value of one tree in Ribnjak Park is 542 EUR. The average diameter at breast height is 57.86 cm with the average age of 96.14 years. Plane trees have the highest value in comparison to other sampled species. Conclusions: Tree values vary depending on age, dimension or aesthetic values. The disadvantage of this method is in the estimation of very old tree value and in high involvement of personal estimation, which creates an opportunity

The Urban Forest and Ecosystem Services: Impacts on Urban Water, Heat, and Pollution Cycles at the Tree, Street, and City Scale.

Science.gov (United States)

Livesley, S J; McPherson, G M; Calfapietra, C

2016-01-01

Many environmental challenges are exacerbated within the urban landscape, such as stormwater runoff and flood risk, chemical and particulate pollution of urban air, soil and water, the urban heat island, and summer heat waves. Urban trees, and the urban forest as a whole, can be managed to have an impact on the urban water, heat, carbon and pollution cycles. However, there is an increasing need for empirical evidence as to the magnitude of the impacts, both beneficial and adverse, that urban trees can provide and the role that climatic region and built landscape circumstance play in modifying those impacts. This special section presents new research that advances our knowledge of the ecological and environmental services provided by the urban forest. The 14 studies included provide a global perspective on the role of trees in towns and cities from five continents. Some studies provide evidence for the cooling benefit of the local microclimate in urban green space with and without trees. Other studies focus solely on the cooling benefit of urban tree transpiration at a mesoscale or on cooling from canopy shade at a street and pedestrian scale. Other studies are concerned with tree species differences in canopy interception of rainfall, water uptake from biofilter systems, and water quality improvements through nutrient uptake from stormwater runoff. Research reported here also considers both the positive and the negative impacts of trees on air quality, through the role of trees in removing air pollutants such as ozone as well as in releasing potentially harmful volatile organic compounds and allergenic particulates. A transdisciplinary framework to support future urban forest research is proposed to better understand and communicate the role of urban trees in urban biogeochemical cycles that are highly disturbed, highly managed, and of paramount importance to human health and well-being. Copyright © by the American Society of Agronomy, Crop Science Society of

Trees and the City: Diversity and Composition along a Neotropical Gradient of Urbanization

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Rubén Ortega-Álvarez

2011-01-01

Full Text Available In this study we assessed tree species richness, density, and composition patterns along a gradient of urbanization of a megacity. Our results show that total, native, and exotic tree densities were highest in green areas where larger spaces are considered for greening purposes. Conversely, total, native, and exotic tree species richness were highest in land uses with intermediate levels of urban development (residential, residential-commercial areas. Not finding highest tree species richness in less developed urban areas suggests that cultural factors may shape the array of species that are planted within cities. Supporting this, tree composition analyses showed that green areas are comprised of different tree species when compared to the rest of the studied urban land uses. Thus, our results suggest that, to increase the ecological quality of cities, residents and managers should be encouraged to select a greater variety of trees to promote heterogeneous green areas.

Carbon storage and sequestration by trees in urban and community areas of the United States.

Science.gov (United States)

Nowak, David J; Greenfield, Eric J; Hoehn, Robert E; Lapoint, Elizabeth

2013-07-01

Carbon storage and sequestration by urban trees in the United States was quantified to assess the magnitude and role of urban forests in relation to climate change. Urban tree field data from 28 cities and 6 states were used to determine the average carbon density per unit of tree cover. These data were applied to statewide urban tree cover measurements to determine total urban forest carbon storage and annual sequestration by state and nationally. Urban whole tree carbon storage densities average 7.69 kg C m(-2) of tree cover and sequestration densities average 0.28 kg C m(-2) of tree cover per year. Total tree carbon storage in U.S. urban areas (c. 2005) is estimated at 643 million tonnes ($50.5 billion value; 95% CI = 597 million and 690 million tonnes) and annual sequestration is estimated at 25.6 million tonnes ($2.0 billion value; 95% CI = 23.7 million to 27.4 million tonnes). Published by Elsevier Ltd.

Calculating the green in green: What's an urban tree worth?

Science.gov (United States)

Gail Wells; Geoffrey Donovan

2010-01-01

For urban dwellers, trees soften a city’s hard edges and surfaces, shade homes and streets, enhance neighborhood beauty, filter the air, mitigate storm runoff, and absorb carbon dioxide. Trees may even reduce crime and improve human health. However, these benefits have not been well quantified, making it difficult for urban planners and property owners to weigh their...

Intra-Urban Variability in Elemental Carbon Deposition to Tree Canopies

Science.gov (United States)

Barrett, T. E.; Ponette-González, A.; Rindy, J. E.; Sheesley, R. J.

2017-12-01

Urban areas cover biomass combustion, EC is a powerful climate-forcing agent and a significant component of fine particulate matter in urban atmospheres. Thus, understanding the factors that govern EC removal in urban areas could help mitigate climate change, while improving air quality for urban residents. EC particles can be removed from the atmosphere in precipitation (wet and fog deposition) or they can settle directly onto receptor surfaces (dry deposition). Only limited measurements indicate that EC deposition is higher in urban than in rural and remote regions. However, EC deposition likely exhibits considerable intra-urban variability, with tree canopies serving as potentially important sinks for EC on the cityscape. The goal of this research is to quantify spatial variability in total (wet + dry) EC deposition to urban tree canopies in the Dallas-Fort Worth Metroplex. Using a stratified non-random sampling design, 41 oak trees (22 post oak (Quercus stellata) and 19 live oak (Quercus virginiana)) were selected near (100 m) for measurements of throughfall (water that falls from the canopy to the forest floor). Additionally, 16 bulk rainfall samplers were deployed in grassy areas with no canopy cover. Results from one rain event indicate a volume weighted mean concentration of 83 µg EC L-1 in post oak throughfall, 36 µg EC L-1 in live oak throughfall, and 4 µg EC L-1 in bulk rainfall. Total EC deposition to oak tree canopies was 2.0 ± 2.1 (SD) mg m-2 for post oak and 0.7 ± 0.3 mg m-2 for live oak. Bulk rainfall deposition was 0.08 ± 0.1 mg m-2. Our preliminary findings show that trees are effective urban air filters, removing 9-25 times more EC from the atmosphere than rainwater alone. Resolving surface controls on atmospheric EC removal is key to developing and assessing near-term climate and air quality mitigation strategies.

Fungal diseases of tree stands under urbanized conditions of Moscow

Directory of Open Access Journals (Sweden)

Smirnova Oksana G.

2013-01-01

Full Text Available Phytosanitary and ecological estimation of tree-stands has been con­ducted at the Forest Experimental Station of Moscow Agricultural Academy and parks of Northeast of Moscow in 2007-2011. Fomes fomentarius was proved to be a very serious pathogen of trees under conditions of Moscow, Piptoporus betulinus, Phellinus igniarius, and Fomitopsis pinicola also occurred and caused damage to trees. This rather bad phytosanitary situation depends on alarming ecological situation in Moscow. At the Forest Experimental Station of Moscow Agricultural Academy a number and cover of lichens decreased. In general, all trees in Moscow are in dynamic equilibrium with the urbanized environment. In connection with this, the following classification of tree-stands was proposed for the urbanized environment: 1 - healthy trees, 2 - affected trees which can be managed, 3 - dry woods, 3a - very diseased. Many tree-stands in investigated regions of Moscow are found to belong to the groups 2 and 3c. All tree-stands must be carefully monitored and managed in order to provide a well-timed decision on the support system for preservation of trees as ‘lungs of city’ and avoid unpredictable tree falling which put people and traffic at risk.

Street trees reduce the negative effects of urbanization on birds.

Science.gov (United States)

Pena, João Carlos de Castro; Martello, Felipe; Ribeiro, Milton Cezar; Armitage, Richard A; Young, Robert J; Rodrigues, Marcos

2017-01-01

The effects of streets on biodiversity is an important aspect of urban ecology, but it has been neglected worldwide. Several vegetation attributes (e.g. street tree density and diversity) have important effects on biodiversity and ecological processes. In this study, we evaluated the influences of urban vegetation-represented by characteristics of street trees (canopy size, proportion of native tree species and tree species richness)-and characteristics of the landscape (distance to parks and vegetation quantity), and human impacts (human population size and exposure to noise) on taxonomic data and functional diversity indices of the bird community inhabiting streets. The study area was the southern region of Belo Horizonte (Minas Gerais, Brazil), a largely urbanized city in the understudied Neotropical region. Bird data were collected on 60 point count locations distributed across the streets of the landscape. We used a series of competing GLM models (using Akaike's information criterion for small sample sizes) to assess the relative contribution of the different sets of variables to explain the observed patterns. Seventy-three bird species were observed exploiting the streets: native species were the most abundant and frequent throughout this landscape. The bird community's functional richness and Rao's Quadratic Entropy presented values lower than 0.5. Therefore, this landscape was favoring few functional traits. Exposure to noise was the most limiting factor for this bird community. However, the average size of arboreal patches and, especially the characteristics of street trees, were able to reduce the negative effects of noise on the bird community. These results show the importance of adequately planning the urban afforestation process: increasing tree species richness, preserving large trees and planting more native trees species in the streets are management practices that will increase bird species richness, abundance and community functional aspects and

Chicago's urban forest ecosystem: Results of the Chicago Urban Forest Climate Project. (Includes executive summary). Forest Service general technical report (Final)

International Nuclear Information System (INIS)

McPherson, E.G.; Nowak, D.J.; Rowntree, R.A.

1994-06-01

Results of the 3-year Chicago Urban Forest Climate Project indicate that there are an estimated 50.8 million trees in the Chicago area of Cook and DuPage Counties; 66 percent of these trees rated in good or excellent condition. During 1991, trees in the Chicago area removed an estimated 6,145 tons of air pollutants, providing air cleansing valued at $9.2 million dollars. These trees also sequester approximately 155,000 tons of carbon per year, and provide residential heating and cooling energy savings that, in turn, reduce carbon emissions from power plants by about 12,600 tons annually. Shade, lower summer air temperatures, and a reduction in windspeed associated with increasing tree cover by 10 percent can lower total heating and cooling energy use by 5 to 10 percent annually ($50 to $90 per dwelling unit). The projected net present value of investment in planting and care of 95,000 trees in Chicago is $38 million ($402 per planted tree), indicating that the long-term benefits of trees are more than twice their costs

Variability in urban soils influences the health and growth of native tree seedlings

Science.gov (United States)

Clara C. Pregitzer; Nancy F. Sonti; Richard A. Hallett

2016-01-01

Reforesting degraded urban landscapes is important due to the many benefits urban forests provide. Urban soils are highly variable, yet little is known about how this variability in urban soils influences tree seedling performance and survival. We conducted a greenhouse study to assess health, growth, and survival of four native tree species growing in native glacial...

Data quality in citizen science urban tree inventories

Science.gov (United States)

Lara A. Roman; Bryant C. Scharenbroch; Johan P.A. Ostberg; Lee S. Mueller; Jason G. Henning; Andrew K. Koeser; Jessica R. Sanders; Daniel R. Betz; Rebecca C. Jordan

2017-01-01

Citizen science has been gaining popularity in ecological research and resource management in general and in urban forestry specifically. As municipalities and nonprofits engage volunteers in tree data collection, it is critical to understand data quality. We investigated observation error by comparing street tree data collected by experts to data collected by less...

Data management for urban tree monitoring -- software requirements

Science.gov (United States)

Deborah J. ​Boyer; Lara A. Roman; Jason G. Henning; Matthew McFarland; Dana Dentice; Sarah C. Low; Casey Thomas; Glen. Abrams

2016-01-01

The creation of this report was organized by the Pennsylvania Horticultural Society (PHS) and the USDA Forest Service Philadelphia Field Station to explore how technology could be used to support the longterm systematic monitoring of urban trees by trained professionals, student interns and volunteers; assist with tree planting and maintenance data processes; and...

Science in the city: Urban trees, forests, and people

Science.gov (United States)

Kathleen L. Wolf

2016-01-01

The article, intended for professional and manager audiences, is an overview of current research in urban forestry. Topics include tree science, forest risks, forest management and assessment, ecosystem services, and urban socio-ecological systems (including governance and stewardship).

Biophysical control of whole tree transpiration under an urban environment in Northern China

Science.gov (United States)

Chen, Lixin; Zhang, Zhiqiang; Li, Zhandong; Tang, Jianwu; Caldwell, Peter; Zhang, Wenjuan

2011-05-01

SummaryUrban reforestation in China has led to increasing debate about the impact of urban trees and forests on water resources. Although transpiration is the largest water flux leaving terrestrial ecosystems, little is known regarding whole tree transpiration in urban environments. In this study, we quantified urban tree transpiration at various temporal scales and examined the biophysical control of the transpiration pattern under different water conditions to understand how trees survive in an urban environment. Concurrent with microclimate and soil moisture measurements, transpiration from C edrus deodara(Roxb)Loud ., Zelkova schneideriana Hend.-Mazz., Euonymus bungeanus Maxim., and Metasequoia glyptostroboides Hu et cheng was measured over a 2-year period using thermal dissipation probe (TDP) techniques. The average monthly transpiration rates reached 12.78 ± 0.73 (S.E.) mm, 1.79 ± 0.16 mm, 10.18 ± 0.55 mm and 19.28 ± 2.24 mm for C. deodara, Z.schneideriana, E. bungeanus and M. glyptostroboides, respectively. Transpiration rates from M. glyptostroboides reported here may need further study as this species showed much higher sap flows and greater transpiration fluctuation under different environmental conditions than other species. Because of deep soil moisture supply, summer dry spells did not reduce transpiration rates even when tree transpiration exceeded rainfall. While vapor pressure deficit ( VPD) was the dominant environmental factor on transpiration, trees controlled canopy conductance effectively to limit transpiration in times of water stress. Our results provide evidence that urban trees could adopt strong physiological control over transpiration under high evaporative demands to avoid dehydration and can make use of water in deeper soil layers to survive summer dry spells. Moreover, urban trees have the ability to make the best use of precipitation when it is limited, and are sensitive to soil and air dryness.

Including public-health benefits of trees in urban-forestry decision making

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Geoffrey H. Donovan

2017-01-01

Research demonstrating the biophysical benefits of urban trees are often used to justify investments in urban forestry. Far less emphasis, however, is placed on the non-bio-physical benefits such as improvements in public health. Indeed, the public-health benefits of trees may be significantly larger than the biophysical benefits, and, therefore, failure to account for...

Stewardship matters: Case studies in establishment success of urban trees

Science.gov (United States)

Lara A. Roman; Lindsey A. Walker; Catherine M. Martineau; David J. Muffly; Susan A. MacQueen; Winnie Harris

2015-01-01

Urban tree planting initiatives aim to provide ecosystem services that materialize decades after planting, therefore understanding tree survival and growth is essential to evaluating planting program performance. Tree mortality is relatively high during the establishment phase, the first few years after planting. Qualitative assessments of programs with particularly...

Ozone uptake by adult urban trees based on sap flow measurement

International Nuclear Information System (INIS)

Wang Hua; Zhou Weiqi; Wang Xiaoke; Gao Fuyuan; Zheng Hua; Tong Lei; Ouyang Zhiyun

2012-01-01

The O 3 uptake in 17 adult trees of six urban species was evaluated by the sap flow-based approach under free atmospheric conditions. The results showed very large species differences in ground area scaled whole-tree ozone uptake (F O 3 ), with estimates ranging from 0.61 ± 0.07 nmol m −2 s −1 in Robinia pseudoacacia to 4.80 ± 1.04 nmol m −2 s −1 in Magnolia liliiflora. However, average F O 3 by deciduous foliages was not significantly higher than that by evergreen ones (3.13 vs 2.21 nmol m −2 s −1 , p = 0.160). Species of high canopy conductance for O 3 (G O 3 ) took up more O 3 than those of low G O 3 , but that their sensitivity to vapour pressure deficit (D) were also higher, and their F O 3 decreased faster with increasing D, regardless of species. The responses of F O 3 to D and total radiation led to the relative high flux of O 3 uptake, indicating high ozone risk for urban tree species. - Highlights: ► O 3 uptake by urban trees varied considering contrasting species and study period. ►The responses of G O 3 to microclimate lead to relative high O 3 uptake by urban trees. ►Many urban species are susceptible to O 3 damage. ►The annual O 3 uptake in our study is greatly less than that from modeling approaches. ►The difference suggests considering the species-specific flux in O 3 risk assessment. - Sap flow-based O 3 uptake among urban species suggests high capacity and variation of ozone uptake, as well as potentially detrimental effects to urban species.

Geospatial Technologies and i-Tree Echo Inventory for Predicting Climate Change on Urban Environment

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Sriharan, S.; Robinson, L.; Ghariban, N.; Comar, M.; Pope, B.; Frey, G.

2015-12-01

Urban forests can be useful both in mitigating climate change and in helping cities adapt to higher temperatures and other impacts of climate change. Understanding and managing the impacts of climate change on the urban forest trees and natural communities will help us maintain their environmental, cultural, and economic benefits. Tree Inventory can provide important information on tree species, height, crown width, overall condition, health and maintenance needs. This presentation will demonstrate that a trees database system is necessary for developing a sustainable urban tree program. Virginia State University (VSU) campus benefits from large number and diversity of trees that are helping us by cleaning the air, retaining water, and providing shade on the buildings to reduce energy cost. The objectives of this study were to develop campus inventory of the trees, identify the tree species, map the locations of the trees with user-friendly tools such as i-Tree Eco and geospatial technologies by assessing the cost/benefit of employing student labor for training and ground validation of the results, and help campus landscape managers implement adaptive responses to climate change impacts. Data was collected on the location, species, and size of trees by using i-Tree urban forestry analysis software. This data was transferred to i-Tree inventory system for demonstrating types of trees, diameter of the trees, height of the trees, and vintage of the trees. The study site was mapped by collecting waypoints with GPS (Global Positioning System) at the trees and uploading these waypoints in ArcMap. The results of this study showed that: (i) students make good field crews, (ii) if more trees were placed in the proper area, the heating and cooling costs will reduce, and (iii) trees database system is necessary for planning, designing, planting, and maintenance, and removal of campus trees Research sponsored by the NIFA Grant, "Urban Forestry Management" (2012-38821-20153).

Urban tree effects on fine particulate matter and human health

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David J. Nowak

2014-01-01

Overall, city trees reduce particulate matter and provide substantial health benefits; but under certain conditions, they can locally increase particulate matter concentrations. Urban foresters need to understand how trees affect particulate matter so they can select proper species and create appropriate designs to improve air quality. This article details trees'...

Mapping Urban Tree Canopy Cover Using Fused Airborne LIDAR and Satellite Imagery Data

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Parmehr, Ebadat G.; Amati, Marco; Fraser, Clive S.

2016-06-01

Urban green spaces, particularly urban trees, play a key role in enhancing the liveability of cities. The availability of accurate and up-to-date maps of tree canopy cover is important for sustainable development of urban green spaces. LiDAR point clouds are widely used for the mapping of buildings and trees, and several LiDAR point cloud classification techniques have been proposed for automatic mapping. However, the effectiveness of point cloud classification techniques for automated tree extraction from LiDAR data can be impacted to the point of failure by the complexity of tree canopy shapes in urban areas. Multispectral imagery, which provides complementary information to LiDAR data, can improve point cloud classification quality. This paper proposes a reliable method for the extraction of tree canopy cover from fused LiDAR point cloud and multispectral satellite imagery data. The proposed method initially associates each LiDAR point with spectral information from the co-registered satellite imagery data. It calculates the normalised difference vegetation index (NDVI) value for each LiDAR point and corrects tree points which have been misclassified as buildings. Then, region growing of tree points, taking the NDVI value into account, is applied. Finally, the LiDAR points classified as tree points are utilised to generate a canopy cover map. The performance of the proposed tree canopy cover mapping method is experimentally evaluated on a data set of airborne LiDAR and WorldView 2 imagery covering a suburb in Melbourne, Australia.

Cooling and energy saving potentials of shade trees and urban lawns in a desert city

International Nuclear Information System (INIS)

Wang, Zhi-Hua; Zhao, Xiaoxi; Yang, Jiachuan; Song, Jiyun

2016-01-01

Highlights: • We developed a numerical framework incorporating trees in an urban canopy model. • Shade trees have more prominent energy saving potential than urban lawns. • The trade-off between water-energy is a key for urban landscape management. • Urban vegetation can significantly alleviate outdoor thermal stress. - Abstract: The use of urban vegetation in cities is a common landscape planning strategy to alleviate the heat island effect as well as to enhance building energy efficiency. The presence of trees in street canyons can effectively reduce environmental temperature via radiative shading. However, resolving shade trees in urban land surface models presents a major challenge in numerical models, especially in predicting the radiative heat exchange in canyons. In this paper, we develop a new numerical framework by incorporating shade trees into an advanced single-layer urban canopy model. This novel numerical framework is applied to Phoenix metropolitan area to investigate the cooling effect of different urban vegetation types and their potentials in saving building energy. It is found that the cooling effect by shading from trees is more significant than that by evapotranspiration from lawns, leading to a considerable saving of cooling load. In addition, analysis of human thermal comfort shows that urban vegetation plays a crucial role in creating a comfortable living environment, especially for cities located in arid or semi-arid region.

Nesting tree characteristics of heronry birds of urban ecosystems in peninsular India: implications for habitat management.

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Roshnath, Ramesh; Sinu, Palatty Allesh

2017-12-01

Wetland ecosystems, particularly the mangrove forest, are the primary wild habitat of heronry birds. However, urban ecosystems have become a favorite breeding habitat of these birds. To provide inputs into the habitat management for conservation of these birds, we investigated the quantitative and qualitative characteristics of nesting trees of heronry birds in the urban environment of the North Kerala region of peninsular India. Census on nesting trees was done in 3 major microhabitats of the urban ecosystem: avenues of national highways and towns, nonresidential plots, and residential areas apart from the mangrove islets in the peri-urban locality. The study found that 174 trees of 22 species hosted 1,928 heronry bird nests in the urban habitats; mangrove forests, although plentiful in the study area, hosted only about 20% of the total nests encountered in the study. Rain trees Samanea saman (43.7%) were the most available nesting tree. The greatest number of nests and nesting trees were encountered on the roads of urban areas, followed by nonresidential areas and residential areas. The differences in the observed frequencies of nesting trees in 3 microhabitats and in 3 types of roads (national highways > state highways > small pocket road) were significant. Canopy spread, girth size, and quality of the trees predicted the tree selection of the heronry birds in urban environments. Therefore, we recommend proper management and notification of the identified nesting trees as protected sites for the conservation of herorny birds.

Health and climate related ecosystem services provided by street trees in the urban environment.

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Salmond, Jennifer A; Tadaki, Marc; Vardoulakis, Sotiris; Arbuthnott, Katherine; Coutts, Andrew; Demuzere, Matthias; Dirks, Kim N; Heaviside, Clare; Lim, Shanon; Macintyre, Helen; McInnes, Rachel N; Wheeler, Benedict W

2016-03-08

Urban tree planting initiatives are being actively promoted as a planning tool to enable urban areas to adapt to and mitigate against climate change, enhance urban sustainability and improve human health and well-being. However, opportunities for creating new areas of green space within cities are often limited and tree planting initiatives may be constrained to kerbside locations. At this scale, the net impact of trees on human health and the local environment is less clear, and generalised approaches for evaluating their impact are not well developed.In this review, we use an urban ecosystems services framework to evaluate the direct, and locally-generated, ecosystems services and disservices provided by street trees. We focus our review on the services of major importance to human health and well-being which include 'climate regulation', 'air quality regulation' and 'aesthetics and cultural services'. These are themes that are commonly used to justify new street tree or street tree retention initiatives. We argue that current scientific understanding of the impact of street trees on human health and the urban environment has been limited by predominantly regional-scale reductionist approaches which consider vegetation generally and/or single out individual services or impacts without considering the wider synergistic impacts of street trees on urban ecosystems. This can lead planners and policymakers towards decision making based on single parameter optimisation strategies which may be problematic when a single intervention offers different outcomes and has multiple effects and potential trade-offs in different places.We suggest that a holistic approach is required to evaluate the services and disservices provided by street trees at different scales. We provide information to guide decision makers and planners in their attempts to evaluate the value of vegetation in their local setting. We show that by ensuring that the specific aim of the intervention, the

Automatic object recognition and change detection of urban trees

NARCIS (Netherlands)

Van der Sande, C.J.

2010-01-01

Monitoring of tree objects is relevant in many current policy issues and relate to the quality of the public space, municipal urban green management, management fees for green areas or Kyoto protocol reporting and all have one thing in common: the need for an up to date tree database. This study,

Quantifying Tree and Soil Carbon Stocks in a Temperate Urban Forest in Northeast China

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Hailiang Lv

2016-09-01

Full Text Available Society has placed greater focus on the ecological service of urban forests; however, more information is required on the variation of carbon (C in trees and soils in different functional forest types, administrative districts, and urban-rural gradients. To address this issue, we measured various tree and soil parameters by sampling 219 plots in the urban forest of the Harbin city region. Averaged tree and soil C stock density (C stocks per unit tree cover for Harbin city were 7.71 (±7.69 kg C·m−2 and 5.48 (±2.86 kg C·m−2, respectively. They were higher than those of other Chinese cities (Shenyang and Changchun, but were much lower than local natural forests. The tree C stock densities varied 2.3- to 3.2-fold among forest types, administrative districts, and ring road-based urban-rural gradients. In comparison, soil organic C (SOC densities varied by much less (1.4–1.5-fold. We found these to be urbanization-dependent processes, which were closely related to the urban-rural gradient data based on ring-roads and settlement history patterns. We estimated that SOC accumulation during the 100-year urbanization of Harbin was very large (5 to 14 thousand tons, accounting for over one quarter of the stored C in trees. Our results provide new insights into the dynamics of above- and below-ground C (especially in soil during the urbanization process, and that a city’s ability to provide C-related ecosystem services increases as it ages. Our findings highlight that urbanization effects should be incorporated into calculations of soil C budgets in regions subject to rapid urban expansion, such as China.

TREE CANOPY COVER MAPPING USING LiDAR IN URBAN BARANGAYS OF CEBU CITY, CENTRAL PHILIPPINES

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J. A. Ejares

2016-06-01

Full Text Available This paper investigates tree canopy cover mapping of urban barangays (smallest administrative division in the Philippines in Cebu City using LiDAR (Light Detection and Ranging. Object-Based Image Analysis (OBIA was used to extract tree canopy cover. Multi-resolution segmentation and a series of assign-class algorithm in eCognition software was also performed to extract different land features. Contextual features of tree canopies such as height, area, roundness, slope, length-width and elliptic fit were also evaluated. The results showed that at the time the LiDAR data was collected (June 24, 2014, the tree cover was around 25.11 % (or 15,674,341.8 m2 of the city’s urban barangays (or 62,426,064.6 m2. Among all urban barangays in Cebu City, Barangay Busay had the highest cover (55.79 % while barangay Suba had the lowest (0.8 %. The 16 barangays with less than 10 % tree cover were generally located in the coastal area, presumably due to accelerated urbanization. Thirty-one barangays have tree cover ranging from 10.59–-27.3 %. Only 3 barangays (i.e., Lahug, Talamban, and Busay have tree cover greater than 30 %. The overall accuracy of the analysis was 96.6 % with the Kappa Index of Agreement or KIA of 0.9. From the study, a grouping can be made of the city’s urban barangays with regards to tree cover. The grouping will be useful to urban planners not only in allocating budget to the tree planting program of the city but also in planning and creation of urban parks and playgrounds.

Modelling short-rotation coppice and tree planting for urban carbon management - a citywide analysis.

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McHugh, Nicola; Edmondson, Jill L; Gaston, Kevin J; Leake, Jonathan R; O'Sullivan, Odhran S

2015-10-01

The capacity of urban areas to deliver provisioning ecosystem services is commonly overlooked and underutilized. Urban populations have globally increased fivefold since 1950, and they disproportionately consume ecosystem services and contribute to carbon emissions, highlighting the need to increase urban sustainability and reduce environmental impacts of urban dwellers. Here, we investigated the potential for increasing carbon sequestration, and biomass fuel production, by planting trees and short-rotation coppice (SRC), respectively, in a mid-sized UK city as a contribution to meeting national commitments to reduce CO 2 emissions.Iterative GIS models were developed using high-resolution spatial data. The models were applied to patches of public and privately owned urban greenspace suitable for planting trees and SRC, across the 73 km 2 area of the city of Leicester. We modelled tree planting with a species mix based on the existing tree populations, and SRC with willow and poplar to calculate biomass production in new trees, and carbon sequestration into harvested biomass over 25 years.An area of 11 km 2 comprising 15% of the city met criteria for tree planting and had the potential over 25 years to sequester 4200 tonnes of carbon above-ground. Of this area, 5·8 km 2 also met criteria for SRC planting and over the same period this could yield 71 800 tonnes of carbon in harvested biomass.The harvested biomass could supply energy to over 1566 domestic homes or 30 municipal buildings, resulting in avoided carbon emissions of 29 236 tonnes of carbon over 25 years when compared to heating by natural gas. Together with the net carbon sequestration into trees, a total reduction of 33 419 tonnes of carbon in the atmosphere could be achieved in 25 years by combined SRC and tree planting across the city. Synthesis and applications . We demonstrate that urban greenspaces in a typical UK city are underutilized for provisioning ecosystem services by trees and

iTree-Hydro: Snow hydrology update for the urban forest hydrology model

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Yang Yang; Theodore A. Endreny; David J. Nowak

2011-01-01

This article presents snow hydrology updates made to iTree-Hydro, previously called the Urban Forest Effects—Hydrology model. iTree-Hydro Version 1 was a warm climate model developed by the USDA Forest Service to provide a process-based planning tool with robust water quantity and quality predictions given data limitations common to most urban areas. Cold climate...

Assessing the ecosystem service of air pollutant removal by urban trees in Guangzhou (China).

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Jim, C Y; Chen, Wendy Y

2008-09-01

In Chinese cities, air pollution has become a serious and aggravating environmental problem undermining the sustainability of urban ecosystems and the quality of urban life. Besides technical solutions to abate air pollution, urban vegetation is increasingly recognized as an alternative ameliorative method by removing some pollutants mainly through dry deposition process. This paper assesses the capability and monetary value of this ecosystem service in Guangzhou city in South China. The results indicated an annual removal of SO(2), NO(2) and total suspended particulates at about 312.03 Mg, and the benefits were valued at RMB90.19 thousand (US$1.00=RMB8.26). More removal was realized by recreational land use due to a higher tree cover. Higher concentration of pollutants in the dry winter months induced more removal. The lower cost of pollution abatement in China generated a relatively subdued monetary value of this environmental benefit in comparison with developed countries. Younger districts with more extensive urban trees stripped more pollutants from the air, and this capacity was anticipated to increase further as their trees gradually reach final dimensions and establish a greater tree cover. Tree cover and pollutant concentration constitute the main factors in pollutant removal by urban trees. The efficiency of atmospheric cleansing by trees in congested Chinese cities could be improved by planting more trees other than shrubs or grass, diversifying species composition and biomass structure, and providing sound green space management. The implications for greenery design were discussed with a view to maximizing this ecosystem service in Chinese cities and other developing metropolises.

Monitoring the Soil Water Availability of Young Urban Trees in Hamburg, Germany

Science.gov (United States)

Titel, Selina; Gröngröft, Alexander; Eschenbach, Annette

2017-04-01

In large cities numerous trees have to be planted each year to replace died off or cut down trees or for greening of constructed roads and newly built quarters. The typical age of planted trees is between five and fifteen years. Often the planting takes place in special planting pits to stimulate the tree growth under the restricted urban conditions. Consequently, trees are surrounded by different soil substrates: the soil from the nursery in the root ball, the special planting pit substrate and the surrounding urban soil which is often anthropogenic influenced. Being relocated in the city, trees have to cope with the warmer urban climate, the soil sealing and compaction and the low water storage capacity of the substrate. All factors together increase the probability of dry phases for roadside trees. The aim of this study is to monitor the soil water availability at sites of planted roadside trees during the first years after planting. Therefore, a measuring design was developed, which works automatically and takes the complex below ground structure of the soil into account. This approach consists of 13 soil water tension sensors inside and outside of each planting pit up to one meter depth connected to a data logger. The monitoring devices will finally be installed at 20 roadside trees (amongst others Quercus cerris, Quercus robur, Acer platanoides 'Fairview') in Hamburg, Germany, to identify phases of drought stress. The young trees were mainly planted in spring 2016. Data of the first year of measurements show, that the water tension varied between the different soil substrates and the depth. In the first year of tree growth in the city, soil in the tree root ball became significantly drier than the surrounding soil material. In late summer 2016 the water tension in the topsoil had the potential to cause drought stress below some trees.

The Effect of Tree Spacing and Size in Urban Areas: Strategies for Mitigating High Temperature in Urban Heat Islands

Science.gov (United States)

Berry, R.; Shandas, V.; Makido, Y.

2017-12-01

Many cities are unintentionally designed to be heat sinks, which absorb the sun's short-wave radiation and reemit as long-wave radiation. Long time reorganization of this `urban heat island' (UHI) phenomena has led researchers and city planners into developing strategies for reducing ambient temperatures through urban design. Specifically, greening areas have proven to reduce the temperature in UHI's, including strategies such as green streets, green facades, and green roofs have been implemented. Among the scientific community there is promoted study of how myriad greening strategies can reduce temperature, relatively limited work has focused on the distribution, density, and quantity of tree campaigns. This paper examines how the spacing and size of trees reduce temperatures differently. A major focus of the paper is to understand how to lower the temperature through tree planting, and provide recommendations to cities that are attempting to solve their own urban heat island issues. Because different cities have different room for planting greenery, we examined which strategies are more efficient given an area constraint. Areas that have less available room might not be able to plant a high density of trees. We compared the different experimental groups varying in density and size of trees against the control to see the effect the trees had. Through calibration with local weather stations, we used a micrometeorology program (ENVI-Met) to model and simulate the different experimental models and how they affect the temperature. The results suggest that some urban designs can reduce ambient temperatures by over 7 0C, and the inclusion of large form trees have the greatest contribution, by reducing temperatures over 15 0C. The results suggest that using specific strategies that combine placement of specific tree configurations with alternative distribution of urban development patterns can help to solve the current challenges of UHI's, and thereby support management

The Role of Native Tree Species on Leaf Breakdown Dynamics of the Invasive Tree of Heaven ( Ailanthus altissima) in an Urban Stream

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Swan, C.; Healey, B.

2005-05-01

Anthropogenic disturbance of ecosystem processes is increasingly being explored in urban settings. One profound impact is the striking increase in the distribution of invasive plant species. For example, Tree of Heaven (Ailanthus altissima, TOH), introduced into the U.S. from Asia in 1784, is a successful colonist of recently deforested habitats. As a result, remnant patches in urban ecosystems have become overrun with this tree species, excluding native species via fast growth and allelopathy. While suffering from human-induced degradation, urban streams still support food webs that function to process riparian-derived organic matter (e.g., leaves, wood). The purpose of this study was to (1) estimate leaf litter breakdown of native tree leaves and those of TOH in an urban stream, (2) study the detritivore feeding rate of the same leaf species, and (3) determine if increasing native species richness of leaf litter can alter breakdown of TOH leaves. Field manipulations of leaf pack composition were done in a highly urbanized stream (>30% upstream urban land use) in Baltimore County, Maryland, USA. This was complimented by a series of laboratory feeding experiments employing similar leaf treatments and local shredding invertebrate taxa. Breakdown of TOH alone was extremely rapid, significantly exceeding that of all native tree species employed. Furthermore, mixing TOH with native tree species, red maple and white oak, substantially reduced TOH decay compared to decay of TOH alone. However, supporting laboratory studies showed that TOH was a preferred resource by shredding invertebrates over all native species. Subsequent analysis of the structural integrity of all leaf species revealed that TOH was the least resistant to force, possibly explaining the counterintuitive decrease of TOH decay in mixtures. We interpret this as meaning the stream invertebrates, while preferring to consume TOH, appeared not to influence TOH decay in mixtures with native species. Instead

Tree diversity in southern California’s urban forest: the interacting roles of social and environmental variables

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Meghan eAvolio

2015-07-01

Full Text Available Socio-economic and environmental drivers are important determinants urban plant richness patterns. The scale at which these patterns are observed in different regions, however, has not been explored. In arid regions, where forests are not native, the majority of the urban forest is planted, and trees are presumably chosen for specific attributes. Here, we investigate the role of spatial scales and the relative importance of environmental versus socio-economic drivers in determining the community structure of southern California’s urban forest. Second, we assess the usefulness of ecosystem service-based traits for understanding patterns of urban biodiversity, compared with species composition data. Third, we test whether resident preferences for specific tree attributes are important for understanding patterns of species composition and diversity. We studied tree communities in 37 neighborhoods in three southern California counties (Los Angeles, Orange, and Riverside. The urban forest in southern California is very diverse with 114 species. Using multiple regression analyses we found socio-economic drivers were generally more important than environmental and the strength of the relationship between urban forest community structure and socio-economic drivers depended on whether we were analyzing within or across counties. There was greater tree richness in wealthier neighborhoods compared with less affluent neighborhoods across all counties and Orange County, but not in Los Angeles or Riverside counties alone. We also found a greater proportion of residential shade trees in hotter neighborhoods than in cooler neighborhoods, which corresponds with survey results of residents’ preferences for tree attributes. Ultimately our study demonstrates that the species richness and functional traits of urban tree communities are influenced by managers’ and residents’ preferences and perceptions of urban tree traits.

The feasibility of remotely sensed data to estimate urban tree dimensions and biomass

Science.gov (United States)

Jun-Hak Lee; Yekang Ko; E. Gregory McPherson

2016-01-01

Accurately measuring the biophysical dimensions of urban trees, such as crown diameter, stem diameter, height, and biomass, is essential for quantifying their collective benefits as an urban forest. However, the cost of directly measuring thousands or millions of individual trees through field surveys can be prohibitive. Supplementing field surveys with remotely sensed...

Impact of urban environmental pollution on growth, leaf damage, and chemical constituents of Warsaw urban trees

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Waldemar Chmielewski; Wojciech Dmuchowski; Stanislaw Suplat

1998-01-01

In the last 10 years, 3.5 percent of the tree population died annually in PolandÕs largest and most polluted cities, which is a problem of economic importance. Dieback of streetside trees in Warsaw is a long term process. It is an effect of biological reactions of trees to unfavorable conditions in the urban environment, particularly air and soil pollution and water...

Residential building energy conservation and avoided power plant emissions by urban and community trees in the United States

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David J. Nowak; Nathaniel Appleton; Alexis Ellis; Eric Greenfield

2017-01-01

Urban trees and forests alter building energy use and associated emissions from power plants by shading buildings, cooling air temperatures and altering wind speeds around buildings. Field data on urban trees were combined with local urban/community tree and land cover maps, modeling of tree effects on building energy use and pollutant emissions, and state energy and...

Assessing the Cooling Benefits of Tree Shade by an Outdoor Urban Physical Scale Model at Tempe, AZ

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Qunshan Zhao

2018-01-01

Full Text Available Urban green infrastructure, especially shade trees, offers benefits to the urban residential environment by mitigating direct incoming solar radiation on building facades, particularly in hot settings. Understanding the impact of different tree locations and arrangements around residential properties has the potential to maximize cooling and can ultimately guide urban planners, designers, and homeowners on how to create the most sustainable urban environment. This research measures the cooling effect of tree shade on building facades through an outdoor urban physical scale model. The physical scale model is a simulated neighborhood consisting of an array of concrete cubes to represent houses with identical artificial trees. We tested and compared 10 different tree densities, locations, and arrangement scenarios in the physical scale model. The experimental results show that a single tree located at the southeast of the building can provide up to 2.3 °C hourly cooling benefits to east facade of the building. A two-tree cluster arrangement provides more cooling benefits (up to 6.6 °C hourly cooling benefits to the central facade when trees are located near the south and southeast sides of the building. The research results confirm the cooling benefits of tree shade and the importance of wisely designing tree locations and arrangements in the built environment.

Trees grow on money: Urban tree canopy cover and environmental justice

Science.gov (United States)

Kirsten Schwarz; Michail Fragkias; Christopher G. Boone; Weiqi Zhou; Melissa McHale; J. Morgan Grove; Jarlath O' Neil-Dunne; Joseph P. McFadden; Geoffrey L. Buckley; Dan Childers; Laura Ogden; Stephanie Pincetl; Diane Pataki; Ali Whitmer; Mary L. Cadenasso; Steven Arthur. Loiselle

2015-01-01

This study examines the distributional equity of urban tree canopy (UTC) cover for Baltimore, MD, Los Angeles, CA, New York, NY, Philadelphia, PA, Raleigh, NC, Sacramento, CA, and Washington, D.C. using high spatial resolution land cover data and census data. Data are analyzed at the Census Block Group levels using Spearman’s correlation, ordinary least squares...

Influence of Environmental Pollution on Leaf Properties of Urban Plane Trees, Platanus orientalis L.

Science.gov (United States)

Pourkhabbaz, Alireza; Rastin, Nayerah; Olbrich, Andrea; Langenfeld-Heyser, Rosemarie

2010-01-01

To investigate whether leaves of plane trees (Platanus orientalis) are damaged by traffic pollution, trees from a megacity (Mashhad, Iran) and a rural area were investigated. Soil and air from the urban centre showed enrichment of several toxic elements, but only lead was enriched in leaves. Leaf size and stomata density were lower at the urban site. At the urban site leaf surfaces were heavily loaded by dust particles but the stomata were not occluded; the cuticle was thinner; other anatomical properties were unaffected suggesting that plane trees can cope with traffic exhaust in megacities. PMID:20577871

Residents’ Support Intentions and Behaviors Regarding Urban Trees Programs: A Structural Equation Modeling-Multi Group Analysis

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Zheng Zhao

2018-01-01

Full Text Available Urban trees are more about people than trees. Urban trees programs need public support and engagement, from the intentions to support to implement actions in supporting the programs. Built upon the theory of planned behavior and Structural Equation Modeling (SEM, this study uses Beijing as a case study to investigate how subjective norm (cognition of urban trees, attitude (benefits residents’ believe urban trees can provide, and perceived behavioral control (the believed ability of what residents can do affect intention and its transformation into implemented of supporting action. A total of 800 residents were interviewed in 2016 and asked about their opinion of neighborhood trees, park trees, and historical trees, and analyzed, respectively. The results show that subjective norm has a significant positive effect on intentions pertaining to historical and neighborhood trees. Attitudes influence intentions, but its overall influence is much lower than that of the subjective norm, indicating that residents are more likely to be influenced by external factors. The perceived behavioral control has the strongest effect among the three, suggesting the importance of public participation in strengthening intention. The transformation from intention to behavior seems relatively small, especially regarding neighborhood trees, suggesting that perceptions and participation need to be strengthened.

Delivering a Multi-Functional and Resilient Urban Forest

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James D. Hale

2015-04-01

Full Text Available Tree planting is widely advocated and applied in urban areas, with large-scale projects underway in cities globally. Numerous potential benefits are used to justify these planting campaigns. However, reports of poor tree survival raise questions about the ability of such projects to deliver on their promises over the long-term. Each potential benefit requires different supporting conditions—relating not only to the type and placement of the tree, but also to the broader urban system within which it is embedded. This set of supporting conditions may not always be mutually compatible and may not persist for the lifetime of the tree. Here, we demonstrate a systems-based approach that makes these dependencies, synergies, and tensions more explicit, allowing them to be used to test the decadal-scale resilience of urban street trees. Our analysis highlights social, environmental, and economic assumptions that are implicit within planting projects; notably that high levels of maintenance and public support for urban street trees will persist throughout their natural lifespan, and that the surrounding built form will remain largely unchanged. Whilst the vulnerability of each benefit may be highly context specific, we identify approaches that address some typical weaknesses, making a functional, resilient, urban forest more attainable.

Mapping Urban Tree Canopy Coverage and Structure using Data Fusion of High Resolution Satellite Imagery and Aerial Lidar

Science.gov (United States)

Elmes, A.; Rogan, J.; Williams, C. A.; Martin, D. G.; Ratick, S.; Nowak, D.

2015-12-01

Urban tree canopy (UTC) coverage is a critical component of sustainable urban areas. Trees provide a number of important ecosystem services, including air pollution mitigation, water runoff control, and aesthetic and cultural values. Critically, urban trees also act to mitigate the urban heat island (UHI) effect by shading impervious surfaces and via evaporative cooling. The cooling effect of urban trees can be seen locally, with individual trees reducing home HVAC costs, and at a citywide scale, reducing the extent and magnitude of an urban areas UHI. In order to accurately model the ecosystem services of a given urban forest, it is essential to map in detail the condition and composition of these trees at a fine scale, capturing individual tree crowns and their vertical structure. This paper presents methods for delineating UTC and measuring canopy structure at fine spatial resolution (body of methods, relying on a data fusion method to combine the information contained in high resolution WorldView-3 satellite imagery and aerial lidar data using an object-based image classification approach. The study area, Worcester, MA, has recently undergone a large-scale tree removal and reforestation program, following a pest eradication effort. Therefore, the urban canopy in this location provides a wide mix of tree age class and functional type, ideal for illustrating the effectiveness of the proposed methods. Early results show that the object-based classifier is indeed capable of identifying individual tree crowns, while continued research will focus on extracting crown structural characteristics using lidar-derived metrics. Ultimately, the resulting fine resolution UTC map will be compared with previously created UTC maps of the same area but for earlier dates, producing a canopy change map corresponding to the Worcester area tree removal and replanting effort.

: Urban design, urban project, urban art, urban composition ... a question of vocabulary?

OpenAIRE

Pinson , Daniel

2014-01-01

Actes à paraître; International audience; The term "urbanism" of Pierre Clerget (1910) put the mess in the practice and the formations in France. Urban planning is thus, on the academic level, a coexistence of disciplinary approaches, which does not help to a multidisciplinary urban training. Thinking about "urban design", after beautifull city, urban composition, or alongside the urban project and other territorial approaches can help to see more clearly in town planning.; Le terme « urbanis...

Effects of a Major Tree Invader on Urban Woodland Arthropods

Science.gov (United States)

2015-01-01

Biological invasions are a major threat to biodiversity; however, the degree of impact can vary depending on the ecosystem and taxa. Here, we test whether a top invader at a global scale, the tree Robinia pseudoacacia (black locust or false acacia), which is known to profoundly change site conditions, significantly affects urban animal diversity. As a first multi-taxon study of this kind, we analyzed the effects of Robinia dominance on 18 arthropod taxa by pairwise comparisons of woodlands in Berlin, Germany, that were dominated by R. pseudoacacia or the native pioneer tree Betula pendula. As a negative effect, abundances of five arthropod taxa decreased (Chilopoda, Formicidae, Diptera, Heteroptera, Hymenoptera); 13 others were not affected. Woodland type affected species composition of carabids and functional groups in spiders, but surprisingly did not decrease alpha and beta diversity of carabid and spider assemblages or the number of endangered species. Tree invasion thus did not induce biotic homogenization at the habitat scale. We detected no positive effects of alien dominance. Our results illustrate that invasions by a major tree invader can induce species turnover in ground-dwelling arthropods, but do not necessarily reduce arthropod species abundances or diversity and might thus contribute to the conservation of epigeal invertebrates in urban settings. Considering the context of invasion impacts thus helps to set priorities in managing biological invasions and can illustrate the potential of novel ecosystems to maintain urban biodiversity. PMID:26359665

Effects of a Major Tree Invader on Urban Woodland Arthropods.

Directory of Open Access Journals (Sweden)

Sascha Buchholz

Full Text Available Biological invasions are a major threat to biodiversity; however, the degree of impact can vary depending on the ecosystem and taxa. Here, we test whether a top invader at a global scale, the tree Robinia pseudoacacia (black locust or false acacia, which is known to profoundly change site conditions, significantly affects urban animal diversity. As a first multi-taxon study of this kind, we analyzed the effects of Robinia dominance on 18 arthropod taxa by pairwise comparisons of woodlands in Berlin, Germany, that were dominated by R. pseudoacacia or the native pioneer tree Betula pendula. As a negative effect, abundances of five arthropod taxa decreased (Chilopoda, Formicidae, Diptera, Heteroptera, Hymenoptera; 13 others were not affected. Woodland type affected species composition of carabids and functional groups in spiders, but surprisingly did not decrease alpha and beta diversity of carabid and spider assemblages or the number of endangered species. Tree invasion thus did not induce biotic homogenization at the habitat scale. We detected no positive effects of alien dominance. Our results illustrate that invasions by a major tree invader can induce species turnover in ground-dwelling arthropods, but do not necessarily reduce arthropod species abundances or diversity and might thus contribute to the conservation of epigeal invertebrates in urban settings. Considering the context of invasion impacts thus helps to set priorities in managing biological invasions and can illustrate the potential of novel ecosystems to maintain urban biodiversity.

Effects of a Major Tree Invader on Urban Woodland Arthropods.

Science.gov (United States)

Buchholz, Sascha; Tietze, Hedwig; Kowarik, Ingo; Schirmel, Jens

2015-01-01

Biological invasions are a major threat to biodiversity; however, the degree of impact can vary depending on the ecosystem and taxa. Here, we test whether a top invader at a global scale, the tree Robinia pseudoacacia (black locust or false acacia), which is known to profoundly change site conditions, significantly affects urban animal diversity. As a first multi-taxon study of this kind, we analyzed the effects of Robinia dominance on 18 arthropod taxa by pairwise comparisons of woodlands in Berlin, Germany, that were dominated by R. pseudoacacia or the native pioneer tree Betula pendula. As a negative effect, abundances of five arthropod taxa decreased (Chilopoda, Formicidae, Diptera, Heteroptera, Hymenoptera); 13 others were not affected. Woodland type affected species composition of carabids and functional groups in spiders, but surprisingly did not decrease alpha and beta diversity of carabid and spider assemblages or the number of endangered species. Tree invasion thus did not induce biotic homogenization at the habitat scale. We detected no positive effects of alien dominance. Our results illustrate that invasions by a major tree invader can induce species turnover in ground-dwelling arthropods, but do not necessarily reduce arthropod species abundances or diversity and might thus contribute to the conservation of epigeal invertebrates in urban settings. Considering the context of invasion impacts thus helps to set priorities in managing biological invasions and can illustrate the potential of novel ecosystems to maintain urban biodiversity.

Tree Species Suitability to Bioswales and Impact on the Urban Water Budget.

Science.gov (United States)

Scharenbroch, Bryant C; Morgenroth, Justin; Maule, Brian

2016-01-01

Water movement between soil and the atmosphere is restricted by hardscapes in the urban environment. Some green infrastructure is intended to increase infiltration and storage of water, thus decreasing runoff and discharge of urban stormwater. Bioswales are a critical component of a water-sensitive urban design (or a low-impact urban design), and incorporation of trees into these green infrastructural components is believed to be a novel way to return stored water to the atmosphere via transpiration. This research was conducted in The Morton Arboretum's main parking lot, which is one of the first and largest green infrastructure installations in the midwestern United States. The parking lot is constructed of permeable pavers and tree bioswales. Trees in bioswales were evaluated for growth and condition and for their effects on water cycling via transpiration. Our data indicate that trees in bioswales accounted for 46 to 72% of total water outputs via transpiration, thereby reducing runoff and discharge from the parking lot. By evaluating the stomatal conductance, diameter growth, and condition of a variety of tree species in these bioswales, we found that not all species are equally suited for bioswales and that not all are equivalent in their transpiration and growth rates, thereby contributing differentially to the functional capacity of bioswales. We conclude that species with high stomatal conductance and large mature form are likely to contribute best to bioswale function. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Tree species composition affects the abundance of rowan (Sorbus aucuparia L.) in urban forests in Finland.

Science.gov (United States)

Hamberg, Leena; Lehvävirta, Susanna; Kotze, D Johan; Heikkinen, Juha

2015-03-15

Recent studies have shown a considerable increase in the abundance of rowan (Sorbus aucuparia) saplings in urban forests in Finland, yet the reasons for this increase are not well understood. Here we investigated whether canopy cover or tree species composition, i.e., the basal areas of different tree species in Norway spruce dominated urban forests, affects the abundances of rowan seedlings, saplings and trees. Altogether 24 urban forest patches were investigated. We sampled the number of rowan and other saplings, and calculated the basal areas of trees. We showed that rowan abundance was affected by tree species composition. The basal area of rowan trees (≥ 5 cm in diameter at breast height, dbh) decreased with increasing basal area of Norway spruce, while the cover of rowan seedlings increased with an increase in Norway spruce basal area. However, a decrease in the abundance of birch (Betula pendula) and an increase in the broad-leaved tree group (Acer platanoides, Alnus glutinosa, Alnus incana, Amelanchier spicata, Prunus padus, Quercus robur, Rhamnus frangula and Salix caprea) coincided with a decreasing number of rowans. Furthermore, rowan saplings were scarce in the vicinity of mature rowan trees. Although it seems that tree species composition has an effect on rowan, the relationship between rowan saplings and mature trees is complex, and therefore we conclude that regulating tree species composition is not an easy way to keep rowan thickets under control in urban forests in Finland. Copyright © 2015 Elsevier Ltd. All rights reserved.

Factors influencing non-native tree species distribution in urban landscapes

Science.gov (United States)

Wayne C. Zipperer

2010-01-01

Non-native species are presumed to be pervasive across the urban landscape. Yet, we actually know very little about their actual distribution. For this study, vegetation plot data from Syracuse, NY and Baltimore, MD were used to examine non-native tree species distribution in urban landscapes. Data were collected from remnant and emergent forest patches on upland sites...

Drought-induced xylem cavitation and hydraulic deterioration: risk factors for urban trees under climate change?

Science.gov (United States)

Savi, Tadeja; Bertuzzi, Stefano; Branca, Salvatore; Tretiach, Mauro; Nardini, Andrea

2015-02-01

Urban trees help towns to cope with climate warming by cooling both air and surfaces. The challenges imposed by the urban environment, with special reference to low water availability due to the presence of extensive pavements, result in high rates of mortality of street trees, that can be increased by climatic extremes. We investigated the water relations and xylem hydraulic safety/efficiency of Quercus ilex trees growing at urban sites with different percentages of surrounding impervious pavements. Seasonal changes of plant water potential and gas exchange, vulnerability to cavitation and embolism level, and morpho-anatomical traits were measured. We found patterns of increasing water stress and vulnerability to drought at increasing percentages of impervious pavement cover, with a consequent reduction in gas exchange rates, decreased safety margins toward embolism development, and increased vulnerability to cavitation, suggesting the occurrence of stress-induced hydraulic deterioration. The amount of impermeable surface and chronic exposure to water stress influence the site-specific risk of drought-induced dieback of urban trees under extreme drought. Besides providing directions for management of green spaces in towns, our data suggest that xylem hydraulics is key to a full understanding of the responses of urban trees to global change. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

Exploring Association between Morphology of Tree Planting and User Activities in Urban Public Space; An opportunity of Urban Public Space Revitalisation

Science.gov (United States)

Shen, Qi; Liu, Yan

2018-03-01

This paper discusses the association between the morphology of tree planting in urban riverside brown field and user activities. With the growth of popularity, the revitalisation of urban public space is also promising. This research used drone photography and mapping to systematically surveys sample sites. An original observation study of user activities proceed in four sample public spaces in Sheffield. The study results found there are huge popularity and duration difference of user activities between various tree planting morphologies and typologies. The public space with lawn and rounded by mature trees attracted most users with the most activity types; the neat and silent public space is the favourite choice of lunch and reading, meanwhile it got the longest activity duration; but the space with sparse morphology and small trees are more likely be forgotten and abandoned. This finding offered a great opportunity for urban public space revitalisation in post-industrial cities.

MillionTreesNYC, Green infrastructure, and urban ecology: building a research agenda

Science.gov (United States)

Jacqueline W.T. Lu; Megan Shane; Erika Svendsen; Lindsay Campbell; Cristiana Fragola; Marianne Krasny; Gina Lovasl; David Maddox; Simon McDonnell; P. Timon McPhearson; Franco Montalto; Andrew Newman; Ellen Pehek; Ruth A. Rae; Richard Stedman; Keith G. Tidball; Lynne Westphal; Tom Whitlow

2009-01-01

MillionTreesNYC is a citywide, public-private initiative with an ambitious goal: to plant and care for one million new trees across New York City's five boroughs by 2017. The Spring 2009 workshop MillionTreesNYC, Green Infrastructure, and Urban Ecology: Building a Research Agenda brought together more than 100 researchers, practitioners and New York City...

Estimating leaf area and leaf biomass of open-grown deciduous urban trees

Science.gov (United States)

David J. Nowak

1996-01-01

Logarithmic regression equations were developed to predict leaf area and leaf biomass for open-grown deciduous urban trees based on stem diameter and crown parameters. Equations based on crown parameters produced more reliable estimates. The equations can be used to help quantify forest structure and functions, particularly in urbanizing and urban/suburban areas.

Tree Productivity Enhanced with Conversion from Forest to Urban Land Covers.

Science.gov (United States)

Briber, Brittain M; Hutyra, Lucy R; Reinmann, Andrew B; Raciti, Steve M; Dearborn, Victoria K; Holden, Christopher E; Dunn, Allison L

2015-01-01

Urban areas are expanding, changing the structure and productivity of landscapes. While some urban areas have been shown to hold substantial biomass, the productivity of these systems is largely unknown. We assessed how conversion from forest to urban land uses affected both biomass structure and productivity across eastern Massachusetts. We found that urban land uses held less than half the biomass of adjacent forest expanses with a plot level mean biomass density of 33.5 ± 8.0 Mg C ha(-1). As the intensity of urban development increased, the canopy cover, stem density, and biomass decreased. Analysis of Quercus rubra tree cores showed that tree-level basal area increment nearly doubled following development, increasing from 17.1 ± 3.0 to 35.8 ± 4.7 cm(2) yr(-1). Scaling the observed stem densities and growth rates within developed areas suggests an aboveground biomass growth rate of 1.8 ± 0.4 Mg C ha(-1) yr(-1), a growth rate comparable to nearby, intact forests. The contrasting high growth rates and lower biomass pools within urban areas suggest a highly dynamic ecosystem with rapid turnover. As global urban extent continues to grow, cities consider climate mitigation options, and as the verification of net greenhouse gas emissions emerges as critical for policy, quantifying the role of urban vegetation in regional-to-global carbon budgets will become ever more important.

Thermic Attenuation on Concrete Sidewalk under Urban Trees. Case Study: Santa Marta – Colombia

OpenAIRE

Carlos Devia; Andrés Torres

2012-01-01

Background and Purpose: Urban trees provide a number of services including shade and thermal attenuation. This is related to morphological and physiological characteristics of trees and may vary between species and even between individuals of the same species. The aim of this work was to identify thermic attenuations on concrete sidewalks under six tropical urban trees with six different types of shadows. Material and Methods: In Santa Marta City, Colombia (10º12´20” N, 74º13´33” W, 10 met...

Urban forest management in New England: Towards a contemporary understanding of tree wardens in Massachusetts communities

Science.gov (United States)

Harper, Richard W.; Bloniarz, David V.; DeStefano, Stephen; Nicolson, Craig

2017-01-01

In the New England states, tree wardens are local officials responsible for the preservation, maintenance and stewardship of municipal public trees. This study explores the emerging professional challenges, duties and responsibilities of tree wardens, from the subject’s point of view, by conducting in-person, semi-structured qualitative research interviews with 50 tree wardens throughout Massachusetts. Many of the findings corroborate previous literature, including that tree wardens are typically housed in a municipal department (often public works or highway), that tree wardens routinely interact with a wide variety of local organisations (representatives from other municipal departments, community volunteer associations) and that as community size increases, tree wardens typically have access to a greater pool of resources to carry out urban forest management. A newer finding is that the subject of urban forest health arose as a topic of great importance for tree wardens, as nearly all interviewees (n = 49) indicated that they monitor for urban forest pests and that they would like further continuing education concerning this subject.

Urban climate modifies tree growth in Berlin

Science.gov (United States)

Dahlhausen, Jens; Rötzer, Thomas; Biber, Peter; Uhl, Enno; Pretzsch, Hans

2018-05-01

Climate, e.g., air temperature and precipitation, differs strongly between urban and peripheral areas, which causes diverse life conditions for trees. In order to compare tree growth, we sampled in total 252 small-leaved lime trees ( Tilia cordata Mill) in the city of Berlin along a gradient from the city center to the surroundings. By means of increment cores, we are able to trace back their growth for the last 50 to 100 years. A general growth trend can be shown by comparing recent basal area growth with estimates from extrapolating a growth function that had been fitted with growth data from earlier years. Estimating a linear model, we show that air temperature and precipitation significantly influence tree growth within the last 20 years. Under consideration of housing density, the results reveal that higher air temperature and less precipitation led to higher growth rates in high-dense areas, but not in low-dense areas. In addition, our data reveal a significantly higher variance of the ring width index in areas with medium housing density compared to low housing density, but no temporal trend. Transferring the results to forest stands, climate change is expected to lead to higher tree growth rates.

Urban climate modifies tree growth in Berlin

Science.gov (United States)

Dahlhausen, Jens; Rötzer, Thomas; Biber, Peter; Uhl, Enno; Pretzsch, Hans

2017-12-01

Climate, e.g., air temperature and precipitation, differs strongly between urban and peripheral areas, which causes diverse life conditions for trees. In order to compare tree growth, we sampled in total 252 small-leaved lime trees (Tilia cordata Mill) in the city of Berlin along a gradient from the city center to the surroundings. By means of increment cores, we are able to trace back their growth for the last 50 to 100 years. A general growth trend can be shown by comparing recent basal area growth with estimates from extrapolating a growth function that had been fitted with growth data from earlier years. Estimating a linear model, we show that air temperature and precipitation significantly influence tree growth within the last 20 years. Under consideration of housing density, the results reveal that higher air temperature and less precipitation led to higher growth rates in high-dense areas, but not in low-dense areas. In addition, our data reveal a significantly higher variance of the ring width index in areas with medium housing density compared to low housing density, but no temporal trend. Transferring the results to forest stands, climate change is expected to lead to higher tree growth rates.

Urban Renewal as an Urban Hegemony Project

Directory of Open Access Journals (Sweden)

Gönül İÇLİ

2012-01-01

Full Text Available There is an organic relationship between capitalism and urban space. Thisrelationship is a dynamic one which reproduces and renovates itself constantlyaccording to the conjuncture of each period and which evolves / changes inparallel with the necessities and rationalities of capital accumulation in historicalprocess. Therefore, neither reproduction of capitalist urban space with the regimeof capital accumulation nor the process of restructuring following a crisis in theregime of capital accumulation with spatial organization of capitalism can becompared independently. Today, in the concrete phase that capitalism hasreached, urban space has become one of the most important parts of direct capitalaccumulation under the hegemony of financial capital. In this context, urbantransformation projects and various strategies ofthe process becomes significantwith the instrumentalization of space by capital rationality. However, this processcarries the internal paradoxes of capitalism into the urban space at the same time,and cities, competing as candidates to be financial centres where the capital hasintensified and centralized, also transforms into spaces of violent socialpolarization. At this point, especially the reformation of squatter settlements has astrategic importance in the process of urban transformation and there are attemptsto attach the urban poor, who are the addressee of the process, under a widerurban hegemony project with the strategy of urban renovation.

The role of trees in urban stormwater management | Science ...

Science.gov (United States)

Urban impervious surfaces convert precipitation to stormwater runoff, which causes water quality and quantity problems. While traditional stormwater management has relied on gray infrastructure such as piped conveyances to collect and convey stormwater to wastewater treatment facilities or into surface waters, cities are exploring green infrastructure to manage stormwater at its source. Decentralized green infrastructure leverages the capabilities of soil and vegetation to infiltrate, redistribute, and otherwise store stormwater volume, with the potential to realize ancillary environmental, social, and economic benefits. To date, green infrastructure science and practice have largely focused on infiltration-based technologies that include rain gardens, bioswales, and permeable pavements. However, a narrow focus on infiltration overlooks other losses from the hydrologic cycle, and we propose that arboriculture – the cultivation of trees and other woody plants – deserves additional consideration as a stormwater control measure. Trees interact with the urban hydrologic cycle by intercepting incoming precipitation, removing water from the soil via transpiration, enhancing infiltration, and bolstering the performance of other green infrastructure technologies. However, many of these interactions are inadequately understood, particularly at spatial and temporal scales relevant to stormwater management. As such, the reliable use of trees for stormwater control depe

The urban forest and ecosystem services: impact on urban water, heat, and pollution cycles at the tree, street, and city scale

Science.gov (United States)

S. J. Livesley; E. G. McPherson; C. Calfapietra

2016-01-01

Many environmental challenges are exacerbated within the urban landscape, such as stormwater runoff and flood risk, chemical and particulate pollution of urban air, soil and water, the urban heat island, and summer heat waves. Urban trees, and the urban forest as a whole, can be managed to have an impact on the urban water, heat, carbon and pollution cycles. However,...

Variation in photosynthesis and stomatal conductance among red maple (Acer rubrum) urban planted cultivars and wildtype trees in the southeastern United States.

Science.gov (United States)

Lahr, Eleanor C; Dunn, Robert R; Frank, Steven D

2018-01-01

Photosynthesis is a fundamental process that trees perform over fluctuating environmental conditions. This study of red maple (Acer rubrum L.) characterizes photosynthesis, stomatal conductance, and water use efficiency in planted cultivars relative to wildtype trees. Red maple is common in cities, yet there is little understanding of how physiological processes affect the long-term growth, condition, and ecosystem services provided by urban trees. In the first year of our study, we measured leaf-level gas exchange and performed short-term temperature curves on urban planted cultivars and on suburban and rural wildtype trees. In the second year, we compared urban planted cultivars and urban wildtype trees. In the first year, urban planted trees had higher maximum rates of photosynthesis and higher overall rates of photosynthesis and stomatal conductance throughout the summer, relative to suburban or rural wildtype trees. Urban planted trees again had higher maximum rates of photosynthesis in the second year. However, urban wildtype trees had higher water use efficiency as air temperatures increased and similar overall rates of photosynthesis, relative to cultivars, in mid and late summer. Our results show that physiological differences between cultivars and wildtype trees may relate to differences in their genetic background and their responses to local environmental conditions, contingent on the identity of the horticultural variety. Overall, our results suggest that wildtype trees should be considered for some urban locations, and our study is valuable in demonstrating how site type and tree type can inform tree planting strategies and improve long-term urban forest sustainability.

Integrated sustainable urban infrastructures in building projects

DEFF Research Database (Denmark)

Nielsen, Susanne Balslev; Quitzau, Maj-Britt; Elle, Morten

2007-01-01

Current strategies in urban planning and development merely promote standardized building solutions, while failing to prioritize innovative approaches of integration between building projects and sustainable urban infrastructures. As a result of this, urban infrastructures – the urban veins...... – are outdated from a sustainability perspective. This paper looks into more holistic ways of approaching building projects and discuss whether this provide a basis for an increased integration of urban infrastructures within building projects. In our study, we especially emphasise how conventional ways...... of approaching building projects are influenced by lock-in of existing infrastructural systems and compare this with two examples of more holistic ways of approaching building projects, developed by two architecture firms. The paper points out that such holistic perspective in building projects provide...

Air pollution removal by urban trees and shrubs in the United States

Science.gov (United States)

David J. Nowak; Daniel E. Crane; Jack C. Stevens

2006-01-01

A modeling study using hourly meteorological and pollution concentration data from across the coterminous United States demonstrates that urban trees remove large amounts of air pollution that consequently improve urban air quality. Pollution removal (03, PM10, NO2, SO2, CO)...

NORTH-EAST ROMANIA AS A FUTURE SOURCE OF TREES FOR URBAN PAVED ENVIRONMENTS IN NORTH-WEST EUROPE

Directory of Open Access Journals (Sweden)

SJÖMAN HENRIK

2009-12-01

Full Text Available Trees are an important feature of the urban environment. The problem today lies not in finding a wide range of well-adapted tree species for park environments, but in finding species suitable for urban paved sites. In terms of north-west Europe, it is unlikely that the limited native dendroflora will provide a large variety of tree species with high tolerance to the environmental stresses characterising urban paved sites in the region. However, other regions with a comparable climate but with a rich dendroflora can potentially provide new tree species and genera well-suited to the growing conditions at urban sites in north-west Europe. This paper examines the potential of a geographical area extending over north-east Romania and the Republic of Moldavia to supply suitable tree species for urban paved sites in Central and Northern Europe (CNE. The study involved comparing the temperature, precipitation, evapotranspiration and water runoff in the woodland area of Iasi, Romania, with those the current inner-city climate of Copenhagen, Denmark and those predicted for Copenhagen 2100. The latter included urban heat island effects and predicted global climate change. The results revealed similar pattern in summer water deficit and temperature between natural woodlands in Iasi and inner-city environment of Copenhagen today. On the other hand, there is a weak match between Iasi and the future Copenhagen. In order to match the future scenario of Copenhagen with the present situation in Iasi, a greater understanding in a early phase that the solution not only depends on suitable tree species, but also on technical solutions being developed in order to have trees in paved environments in the future. On the basis of precipitation and temperature data, natural woodlands in north-east Romania have the potential to be a source of suitable trees for urban paved environments in the CNE region, even for a future climate if other aspects in the planning of trees

The Urban Tree as a Tool to Mitigate the Urban Heat Island in Mexico City: A Simple Phenomenological Model.

Science.gov (United States)

Ballinas, Mónica; Barradas, Víctor L

2016-01-01

The urban heat island (UHI) is mainly a nocturnal phenomenon, but it also appears during the day in Mexico City. The UHI may affect human thermal comfort, which can influence human productivity and morbidity in the spring/summer period. A simple phenomenological model based on the energy balance was developed to generate theoretical support of UHI mitigation in Mexico City focused on the latent heat flux change by increasing tree coverage to reduce sensible heat flux and air temperature. Half-hourly data of the urban energy balance components were generated in a typical residential/commercial neighborhood of Mexico City and then parameterized using easily measured variables (air temperature, humidity, pressure, and visibility). Canopy conductance was estimated every hour in four tree species, and transpiration was estimated using sap flow technique and parameterized by the envelope function method. Averaged values of net radiation, energy storage, and sensible and latent heat flux were around 449, 224, 153, and 72 W m, respectively. Daily tree transpiration ranged from 3.64 to 4.35 Ld. To reduce air temperature by 1°C in the studied area, 63 large would be required per hectare, whereas to reduce the air temperature by 2°C only 24 large trees would be required. This study suggests increasing tree canopy cover in the city cannot mitigate UHI adequately but requires choosing the most appropriate tree species to solve this problem. It is imperative to include these types of studies in tree selection and urban development planning to adequately mitigate UHI. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Tree Productivity Enhanced with Conversion from Forest to Urban Land Covers.

Directory of Open Access Journals (Sweden)

Brittain M Briber

Full Text Available Urban areas are expanding, changing the structure and productivity of landscapes. While some urban areas have been shown to hold substantial biomass, the productivity of these systems is largely unknown. We assessed how conversion from forest to urban land uses affected both biomass structure and productivity across eastern Massachusetts. We found that urban land uses held less than half the biomass of adjacent forest expanses with a plot level mean biomass density of 33.5 ± 8.0 Mg C ha(-1. As the intensity of urban development increased, the canopy cover, stem density, and biomass decreased. Analysis of Quercus rubra tree cores showed that tree-level basal area increment nearly doubled following development, increasing from 17.1 ± 3.0 to 35.8 ± 4.7 cm(2 yr(-1. Scaling the observed stem densities and growth rates within developed areas suggests an aboveground biomass growth rate of 1.8 ± 0.4 Mg C ha(-1 yr(-1, a growth rate comparable to nearby, intact forests. The contrasting high growth rates and lower biomass pools within urban areas suggest a highly dynamic ecosystem with rapid turnover. As global urban extent continues to grow, cities consider climate mitigation options, and as the verification of net greenhouse gas emissions emerges as critical for policy, quantifying the role of urban vegetation in regional-to-global carbon budgets will become ever more important.

Semi-Automated Approach for Mapping Urban Trees from Integrated Aerial LiDAR Point Cloud and Digital Imagery Datasets

Science.gov (United States)

Dogon-Yaro, M. A.; Kumar, P.; Rahman, A. Abdul; Buyuksalih, G.

2016-09-01

Mapping of trees plays an important role in modern urban spatial data management, as many benefits and applications inherit from this detailed up-to-date data sources. Timely and accurate acquisition of information on the condition of urban trees serves as a tool for decision makers to better appreciate urban ecosystems and their numerous values which are critical to building up strategies for sustainable development. The conventional techniques used for extracting trees include ground surveying and interpretation of the aerial photography. However, these techniques are associated with some constraints, such as labour intensive field work and a lot of financial requirement which can be overcome by means of integrated LiDAR and digital image datasets. Compared to predominant studies on trees extraction mainly in purely forested areas, this study concentrates on urban areas, which have a high structural complexity with a multitude of different objects. This paper presented a workflow about semi-automated approach for extracting urban trees from integrated processing of airborne based LiDAR point cloud and multispectral digital image datasets over Istanbul city of Turkey. The paper reveals that the integrated datasets is a suitable technology and viable source of information for urban trees management. As a conclusion, therefore, the extracted information provides a snapshot about location, composition and extent of trees in the study area useful to city planners and other decision makers in order to understand how much canopy cover exists, identify new planting, removal, or reforestation opportunities and what locations have the greatest need or potential to maximize benefits of return on investment. It can also help track trends or changes to the urban trees over time and inform future management decisions.

Using AVIRIS data and multiple-masking techniques to map urban forest trees species

Science.gov (United States)

Q. Xiao; S.L. Ustin; E.G. McPherson

2004-01-01

Tree type and species information are critical parameters for urban forest management, benefit cost analysis and urban planning. However, traditionally, these parameters have been derived based on limited field samples in urban forest management practice. In this study we used high-resolution Airborne Visible Infrared Imaging Spectrometer (AVIRIS) data and multiple-...

De-icing salt contamination reduces urban tree performance in structural soil cells.

Science.gov (United States)

Ordóñez-Barona, Camilo; Sabetski, Vadim; Millward, Andrew A; Steenberg, James

2018-03-01

Salts used for de-icing roads and sidewalks in northern climates can have a significant impact on water quality and vegetation. Sub-surface engineering systems, such as structural soil cells, can regulate water runoff and pollutants, and provide the necessary soil volume and irrigation to grow trees. However, the ability of such systems to manage de-icing salt contamination, and the impact of this contamination on the trees growing in them, have not been evaluated. We report on an field investigation of de-icing salt contamination in structural cells in two street-revitalization projects in Toronto, Canada, and the impact of this contamination on tree performance. We analyzed soil chemistry and collected tree attributes; these data were examined together to understand the effect of salinity on tree mortality rates and foliar condition. Data collected from continuous soil salinity loggers from April to June for one of the two sites were used to determine whether there was a long-term accumulation of salts in the soils. Results for both sites indicate that both sites displayed high salinity and alkalinity, with levels elevated beyond those suggested before those reported to cause negative tree effects. For one site, trees that were alive and trees that had a better foliar condition had significantly lower levels of soil salinity and alkalinity than other trees. High salinity and alkalinity in the soil were also associated with lower nutrient levels for both sites. Although tests for salinity accumulation in the soils of one site were negative, a longer monitoring of the soil conditions within the soil cells is warranted. Despite structural cells being increasingly utilized for their dual role in storm-water management and tree establishment, there may be a considerable trade-off between storm-water management and urban-forest function in northern climates where de-icing salt application continues to be commonplace. Copyright © 2017 Elsevier Ltd. All rights reserved.

Does beauty still matter? Experiential and utilitarian values of urban trees

Science.gov (United States)

Herbert W. Schroeder

2011-01-01

A major focus of early research on the social aspects of urban forestry was on how people perceive and value the beauty of trees in cities and towns. Since then, researchers have found that besides aesthetic enjoyment, the presence of urban forest vegetation may provide additional benefits such as stress relief, recovery from mental fatigue, stronger social ties,...

MillionTreesNYC, Green Infrastructure and Urban Ecology Symposium March 5-6, 2010

Directory of Open Access Journals (Sweden)

Erika S. Svendsen

2010-01-01

Full Text Available The MillionTreesNYC Subcommittee on Research and Evaluation was formed shortly following the 2007 launch of MillionTreesNYC, a citywide, public-private initiative with an ambitious goal: to plant and care for one million new trees across New York City’s five boroughs by 2017. Members of this committee are comprised of academics, government researchers and local practitioners with experience in the fields of natural resource management and community development.On March 5-6, 2010, over two hundred researchers and practitioners came together at The New School to showcase scientific innovation in the field of urban forestry and greening. The MillionTreesNYC, Green Infrastructure and Urban Ecology Research Symposium engaged professionals from a broad range of disciplines including sociology, planning, epidemiology, earth sciences, hydrology, forestry, ecology, and design who were uniquely positioned to discuss new ideas.

SEMI-AUTOMATED APPROACH FOR MAPPING URBAN TREES FROM INTEGRATED AERIAL LiDAR POINT CLOUD AND DIGITAL IMAGERY DATASETS

Directory of Open Access Journals (Sweden)

M. A. Dogon-Yaro

2016-09-01

Full Text Available Mapping of trees plays an important role in modern urban spatial data management, as many benefits and applications inherit from this detailed up-to-date data sources. Timely and accurate acquisition of information on the condition of urban trees serves as a tool for decision makers to better appreciate urban ecosystems and their numerous values which are critical to building up strategies for sustainable development. The conventional techniques used for extracting trees include ground surveying and interpretation of the aerial photography. However, these techniques are associated with some constraints, such as labour intensive field work and a lot of financial requirement which can be overcome by means of integrated LiDAR and digital image datasets. Compared to predominant studies on trees extraction mainly in purely forested areas, this study concentrates on urban areas, which have a high structural complexity with a multitude of different objects. This paper presented a workflow about semi-automated approach for extracting urban trees from integrated processing of airborne based LiDAR point cloud and multispectral digital image datasets over Istanbul city of Turkey. The paper reveals that the integrated datasets is a suitable technology and viable source of information for urban trees management. As a conclusion, therefore, the extracted information provides a snapshot about location, composition and extent of trees in the study area useful to city planners and other decision makers in order to understand how much canopy cover exists, identify new planting, removal, or reforestation opportunities and what locations have the greatest need or potential to maximize benefits of return on investment. It can also help track trends or changes to the urban trees over time and inform future management decisions.

Analysis of tree bark samples for air pollution biomonitoring of an urban area

International Nuclear Information System (INIS)

Martins, Ana Paula G.; Negri, Elnara M.; Saldiva, Paulo H.N.

2009-01-01

Air pollution is receiving much attention as a public health problem around the world due to its adverse health effects from exposures by urban populations. Within this context, the use of vegetal biomonitoring to evaluate air quality has been investigated throughout the world. Air pollutant levels are high in the city of Sao Paulo, SP, Brazil and being the vehicle emissions its main source. The aim of this study was to evaluate concentrations of As, Ba, Br, Ca, Co, Cr, Cu, Fe, Mn, Pb, S, Sb and Zn in tree bark samples used as biomonitor of urban air pollution. Concentrations of these elements were determined in barks collected in trees of the Ibirapuera Park, one of the biggest and most visited parks of the city of Sao Paulo city. Samples of tree barks were also collected in a site outside the city of Sao Paulo, in a rural area of Embu-Guacu, considered as a control site. The element concentrations were determined by the methods of Instrumental Neutron Activation Analysis (INAA) and of Energy Dispersive X-ray Fluorescence Spectrometry (EDXRF). The findings of this study showed that tree bark samples may be used as biomonitors of urban air pollution in a micro scale, and both techniques, INAA and EDXRF, can be used to evaluate element concentrations in tree bark samples. (author)

Carbon dioxide reduction through urban forestry: guidelines for professional and volunteer tree planters

Science.gov (United States)

E. Gregory McPherson; James R. Simpson

1999-01-01

Carbon dioxide reduction through urban forestry—Guidelines for professional and volunteer tree planters has been developed by the Pacific Southwest Research Station’s Western Center for Urban Forest Research and Education as a tool for utilities, urban foresters and arborists, municipalities, consultants, non-profit organizations and others to...

Does tree planting pay us back? Lessons from Sacramento, CA

Science.gov (United States)

Yekang Ko; Lara A. Roman; E. Gregory McPherson; Junhak. Lee

2016-01-01

The past decade could be called a renaissance of urban forestry, driven by mayoral tree planting initiatives and increased attention on city trees as green infrastructure. The political support for urban greening has been fueled by research that quantifies and projects the ecosystem services of planting initiatives (Young and McPherson 2013). Major cities have been...

Using stable isotopes in tree rings to evaluate the impact of urban pollution on CO2 uptake by forests

International Nuclear Information System (INIS)

Savard, M.M.; Begin, Ch.; Marion, J.

2004-01-01

Contributions addressing the impact of industrial activities on tree growth are scarce; likewise, only a few studies document δ 13 C values in growth rings of natural specimens subjected to potentially toxic industrial emissions. These last studies suggest that the SO 2 emissions affect the physiology of trees and induce changes in their carbon isotope ratios. It has been reported that copper-smelter emissions reduce the C uptake of exposed trees by 35 % to 6 % relatively to unexposed trees, in growth stands located between 9 and 120 km from the smelter. In the context of the globally increasing concentrations of CO 2 in the atmosphere, what is the net impact of the large-scale annual reduction of CO 2 uptake induced by phyto-toxic pollutants? What should we expect for trees growing in regions submitted to urban diffuse pollution? It has been recently suggested on the basis of plant biomass measurements in the New York region that urban pollution can relatively reduce plant growth, but the effect is apparently greater in distant rural sites than in peri-urban and urban ones. Is this representative of numerous urban settings? If the answer to this question is yes, the pollution-effect parameter should be considered in the global annual forest C budget, particularly for the highly industrialized northern hemisphere. The specific objectives of this study are to: (1) measure the tissue increments of the stems and determine the C isotopic ratios in tree-ring cellulose of selected trees undergoing pollution stress in selected peri-urban stands; (2) present a secular time series of the CO 2 uptake by forests peripheral to a large urban region; and (3) evaluate stable isotope dendro-geochemistry as a proxy for past changes of air quality in urban and peri-urban settings. (authors)

Modeling of air pollutant removal by dry deposition to urban trees using a WRF/CMAQ/i-Tree Eco coupled system

Science.gov (United States)

Maria Theresa I. Cabaraban; Charles N. Kroll; Satoshi Hirabayashi; David J. Nowak

2013-01-01

A distributed adaptation of i-Tree Eco was used to simulate dry deposition in an urban area. This investigation focused on the effects of varying temperature, LAI, and NO2 concentration inputs on estimated NO2 dry deposition to trees in Baltimore, MD. A coupled modeling system is described, wherein WRF provided temperature...

Thermic Attenuation on Concrete Sidewalk under Urban Trees. Case Study: Santa Marta – Colombia

Directory of Open Access Journals (Sweden)

Carlos Devia

2012-12-01

Full Text Available Background and Purpose: Urban trees provide a number of services including shade and thermal attenuation. This is related to morphological and physiological characteristics of trees and may vary between species and even between individuals of the same species. The aim of this work was to identify thermic attenuations on concrete sidewalks under six tropical urban trees with six different types of shadows. Material and Methods: In Santa Marta City, Colombia (10º12´20” N, 74º13´33” W, 10 meters above sea level and 31ºC temperature, we selected six trees (species with different types of shade, and they are evaluated for soil temperature and the temperature in the shade and off throughout the day for four different days of the year. ANOVA and t-tests were performed with R program in order to identify the influence of the specie, the day, the hour and the position (at the thermic comfort level, surface temperature on the temperature results obtained. Results and Conclusion: Some trees have the most translucent shadows most likely due to nictinastic movements and consequently less temperature attenuation. On the other hand, other trees have denser shadows and can generate more substantial thermic attenuations. Regarding temperature data, the hour of the day shows the greatest influence on the variability of air temperature and the species shows the greatest influence on the variability of surface temperature. Honey berry (Meliccoca bijugatus and Malay almond (Terminalia atappa trees have denser shadows and can generate more substantial thermic attenuations. Tree physiology can play an important role in temperature attenuation in cities as a result of shadow effects and can be applied as a criterion to select urban trees in tropical cities.

Urban air quality management : effects of trees on air pollution concentration in urban street canyon

NARCIS (Netherlands)

Salim, S.M.; Buccolieri, R.; Chan, A.; Sabatino, Di S.; Gromke, C.

2009-01-01

The aerodynamic effects of avenue-like tree planting on air flow and traffic-originated pollutant dispersion in urban built-up areas (i.e. street canyons of width to height ratio, W/H=1) are investigated using computational fluid dynamics techniques and complemented with extensive wind tunnel

Disconnecting the autopilot in urban water projects

DEFF Research Database (Denmark)

Nielsen, Susanne Balslev; Jensen, Marina Bergen; Øhlenschlæger, Ny

2011-01-01

How can we motivate urban planners, water utilities and house owners to collaborate about sustainable urban water projects and to aim for solutions that go beyond the narrow perspective of individual stakeholder interests? A concept for framing a multidisciplinary learning process is developed...... the early stages of an urban water project. To realise new sustainable urban water designs a project team will need to engage and get acceptance from internal and external stakeholders, and this calls for communication and social skills rather than technical skills. The paper identifies potential...

Challenges for tree officers to enhance the provision of regulating ecosystem services from urban forests.

Science.gov (United States)

Davies, Helen J; Doick, Kieron J; Hudson, Malcolm D; Schreckenberg, Kate

2017-07-01

Urbanisation and a changing climate are leading to more frequent and severe flood, heat and air pollution episodes in Britain's cities. Interest in nature-based solutions to these urban problems is growing, with urban forests potentially able to provide a range of regulating ecosystem services such as stormwater attenuation, heat amelioration and air purification. The extent to which these benefits are realized is largely dependent on urban forest management objectives, the availability of funding, and the understanding of ecosystem service concepts within local governments, the primary delivery agents of urban forests. This study aims to establish the extent to which British local authorities actively manage their urban forests for regulating ecosystem services, and identify which resources local authorities most need in order to enhance provision of ecosystem services by Britain's urban forests. Interviews were carried out with staff responsible for tree management decisions in fifteen major local authorities from across Britain, selected on the basis of their urban nature and high population density. Local authorities have a reactive approach to urban forest management, driven by human health and safety concerns and complaints about tree disservices. There is relatively little focus on ensuring provision of regulating ecosystem services, despite awareness by tree officers of the key role that urban forests can play in alleviating chronic air pollution, flood risk and urban heat anomalies. However, this is expected to become a greater focus in future provided that existing constraints - lack of understanding of ecosystem services amongst key stakeholders, limited political support, funding constraints - can be overcome. Our findings suggest that the adoption of a proactive urban forest strategy, underpinned by quantified and valued urban forest-based ecosystem services provision data, and innovative private sector funding mechanisms, can facilitate a change to a

Grading of Parameters for Urban Tree Inventories by City Officials, Arborists, and Academics Using the Delphi Method

Science.gov (United States)

Östberg, Johan; Delshammar, Tim; Wiström, Björn; Nielsen, Anders Busse

2013-03-01

Tree inventories are expensive to conduct and update, so every inventory carried out must be maximized. However, increasing the number of constituent parameters increases the cost of performing and updating the inventory, illustrating the need for careful parameter selection. This article reports the results of a systematic expert rating of tree inventories aiming to quantify the relative importance of each parameter. Using the Delphi method, panels comprising city officials, arborists, and academics rated a total of 148 parameters. The total mean score, the top ranking parameters, which can serve as a guide for decision-making at practical level and for standardization of tree inventories, were: Scientific name of the tree species and genera, Vitality, Coordinates, Hazard class, and Identification number. The study also examined whether the different responsibilities and usage of urban tree databases among organizations and people engaged in urban tree inventories affected their prioritization. The results revealed noticeable dissimilarities in the ranking of parameters between the panels, underlining the need for collaboration between the research community and those commissioning, administrating, and conducting inventories. Only by applying such a transdisciplinary approach to parameter selection can urban tree inventories be strengthened and made more relevant.

Role of Biogenic Volatile Organic Compounds (BVOC) emitted by urban trees on ozone concentration in cities: A review

International Nuclear Information System (INIS)

Calfapietra, C.; Fares, S.; Manes, F.; Morani, A.; Sgrigna, G.; Loreto, F.

2013-01-01

Biogenic Volatile Organic Compounds (BVOC) play a critical role in biosphere–atmosphere interactions and are key factors of the physical and chemical properties of the atmosphere and climate. However, few studies have been carried out at urban level to investigate the interactions between BVOC emissions and ozone (O 3 ) concentration. The contribution of urban vegetation to the load of BVOCs in the air and the interactions between biogenic emissions and urban pollution, including the likely formation of O 3 , needs to be investigated, but also the effects of O 3 on the biochemical reactions and physiological conditions leading to BVOC emissions are largely unknown. The effect of BVOC emission on the O 3 uptake by the trees is further complicating the interactions BVOC–O 3 , thus making challenging the estimation of the calculation of BVOC effect on O 3 concentration at urban level. -- Highlights: • We examine the role of BVOC emitted from urban trees for O 3 formation in our cities. • We state that the high BVOC emitter trees are dangerous especially in VOC limited conditions for ozone formation. • We conclude that the choice of the tree species can be very important for the quality of the air in our cities. -- BVOC emission from urban trees can be very important for ozone concentration

Build Artifacts in Sustainable Urban Projects

DEFF Research Database (Denmark)

Pinheiro-Croisel, Rebecca; Hernes, Tor

2015-01-01

This paper explores innovation and social behaviourist theory in relation to sustainable urban projects in the highly institutionalized public sector (towns). Using empirical data from France, we examine the dynamics of a design process in which unexpected practices generated innovative urban...... into a movement of collective action, which presupposed the acquisition of a new identity. Ultimately, our objective is to combine social behaviourist theory and innovation theory and to facilitate innovative design in urban projects....

Determinants of establishment survival for residential trees in Sacramento County, CA

Science.gov (United States)

Lara A. Roman; John J. Battles; Joe R. McBride

2014-01-01

Urban forests can provide ecosystem services that motivate tree planting campaigns, and tree survival is a key element of program success and projected benefits. We studied survival in a shade tree give-away program in Sacramento, CA, monitoring a cohort of young trees for five years on single-family residential properties. We used conditional inference trees to...

MillionTreesNYC, green infrastructure and urban ecology symposium March 5-6, 2010

Science.gov (United States)

Erika S. Svendsen; Jacqueline W.T. Lu

2010-01-01

On March 5-6, 2010, over two hundred researchers and practitioners came together at The New School to showcase scientific innovation in the field of urban forestry and greening. The MillionTreesNYC, Green Infrastructure and Urban Ecology Research Symposium engaged professionals from a broad range of disciplines including sociology, planning,...

Soil surface temperatures reveal moderation of the urban heat island effect by trees and shrubs.

Science.gov (United States)

Edmondson, J L; Stott, I; Davies, Z G; Gaston, K J; Leake, J R

2016-09-19

Urban areas are major contributors to air pollution and climate change, causing impacts on human health that are amplified by the microclimatological effects of buildings and grey infrastructure through the urban heat island (UHI) effect. Urban greenspaces may be important in reducing surface temperature extremes, but their effects have not been investigated at a city-wide scale. Across a mid-sized UK city we buried temperature loggers at the surface of greenspace soils at 100 sites, stratified by proximity to city centre, vegetation cover and land-use. Mean daily soil surface temperature over 11 months increased by 0.6 °C over the 5 km from the city outskirts to the centre. Trees and shrubs in non-domestic greenspace reduced mean maximum daily soil surface temperatures in the summer by 5.7 °C compared to herbaceous vegetation, but tended to maintain slightly higher temperatures in winter. Trees in domestic gardens, which tend to be smaller, were less effective at reducing summer soil surface temperatures. Our findings reveal that the UHI effects soil temperatures at a city-wide scale, and that in their moderating urban soil surface temperature extremes, trees and shrubs may help to reduce the adverse impacts of urbanization on microclimate, soil processes and human health.

Extraction of Urban Trees from Integrated Airborne Based Digital Image and LIDAR Point Cloud Datasets - Initial Results

Science.gov (United States)

Dogon-yaro, M. A.; Kumar, P.; Rahman, A. Abdul; Buyuksalih, G.

2016-10-01

Timely and accurate acquisition of information on the condition and structural changes of urban trees serves as a tool for decision makers to better appreciate urban ecosystems and their numerous values which are critical to building up strategies for sustainable development. The conventional techniques used for extracting tree features include; ground surveying and interpretation of the aerial photography. However, these techniques are associated with some constraint, such as labour intensive field work, a lot of financial requirement, influences by weather condition and topographical covers which can be overcome by means of integrated airborne based LiDAR and very high resolution digital image datasets. This study presented a semi-automated approach for extracting urban trees from integrated airborne based LIDAR and multispectral digital image datasets over Istanbul city of Turkey. The above scheme includes detection and extraction of shadow free vegetation features based on spectral properties of digital images using shadow index and NDVI techniques and automated extraction of 3D information about vegetation features from the integrated processing of shadow free vegetation image and LiDAR point cloud datasets. The ability of the developed algorithms shows a promising result as an automated and cost effective approach to estimating and delineated 3D information of urban trees. The research also proved that integrated datasets is a suitable technology and a viable source of information for city managers to be used in urban trees management.

The value of urban tree cover: A hedonic property price model in Ramsey and Dakota Counties, Minnesota, USA

Science.gov (United States)

Heather Sander; Stephen Polasky; Robert. Haight

2010-01-01

Urban tree cover benefits communities. These benefits' economic values, however, are poorly recognized and often ignored by landowners and planners. We use hedonic property price modeling to estimate urban tree cover's value in Dakota and Ramsey Counties, MN, USA, predicting housing value as a function of structural, neighborhood, and environmental variables...

Context-sensitive extraction of tree crown objects in urban areas using VHR satellite images

NARCIS (Netherlands)

Ardila, Juan Pablo; Bijker, W.; Tolpekin, V.A.; Stein, A.

2012-01-01

Municipalities need accurate and updated inventories of urban vegetation in order to manage green resources and estimate their return on investment in urban forestry activities. Earlier studies have shown that semi-automatic tree detection using remote sensing is a challenging task. This study aims

Predictors of mortality for juvenile trees in a residential urban-to-rural cohort in Worcester, MA

Science.gov (United States)

Arthur Elmes; John Rogan; Lara A. Roman; Christopher A. Williams; Samuel J. Ratick; David J. Nowak; Deborah G. Martin

2018-01-01

This paper explores predictors of juvenile tree mortality in a newly planted cohort in Worcester, MA, following an episode of large-scale tree removal necessitated by an Asian Longhorned Beetle (Anoplophora glabripennis, ALB) eradication program. Trees are increasingly seen as important providers of ecosystem services for urban areas, including:...

Ecophysiological and seasonal variations in Cd, Pb, Zn, and Ni concentrations in the leaves of urban deciduous trees in Istanbul

International Nuclear Information System (INIS)

Baycu, Guelriz; Tolunay, Doganay; Ozden, Hakan; Guenebakan, Suereyya

2006-01-01

The concentrations of Cd, Pb, Zn and Ni were measured in the leaves of 7 species of deciduous trees, from the urban sites of Istanbul, in both the Spring and Autumn seasons. We detected some differences in the heavy metal concentrations of the control and urban site samples of identical species. Highest concentrations of Cd were detected in Populus, Pb in Aesculus and Robinia, Zn in Populus, and Ni in Robinia and Fraxinus. Lowest chlorophyll content and highest peroxidase (POD) activity was found in the urban site samples of Acer. We have found a positive correlation between the increase in the POD activity and the Pb concentration in Populus. Generally, the tree species investigated in this study, are considered to have different tolerance levels to heavy metal pollution. The data obtained show that the chlorophyll content and the POD activity may be used as heavy metal stress biomarkers in the urban trees. - Ecophysiological changes in the urban trees may be used as heavy metal stress biomarkers

Trees in urban street canyons and their impact on the dispersion of automobile exhausts

NARCIS (Netherlands)

Gromke, C.B.; Ruck, B.

2007-01-01

The aim of the present study is to clarify the influence of trees on the dispersion of automobile exhausts in urban street canyons. For this purpose, measurements have been performed with a small scale wind tunnel model of an idealized, isolated street canyon with model trees placed along the canyon

Effects of trees on the dilution of vehicle exhaust emissions in urban street canyons

NARCIS (Netherlands)

Gromke, C.B.; Ruck, B.

2009-01-01

In order to investigate the natural ventilation and air quality of urban street canyons with trees, boundary layer wind tunnel studies at a small-scale model have been performed. Concentrations in street canyons with a tracer gas emitting line source at the ground level and one row of trees arranged

"Trees and Things That Live in Trees": Three Children with Special Needs Experience the Project Approach

Science.gov (United States)

Griebling, Susan; Elgas, Peg; Konerman, Rachel

2015-01-01

The authors report on research conducted during a project investigation undertaken with preschool children, ages 3-5. The report focuses on three children with special needs and the positive outcomes for each child as they engaged in the project Trees and Things That Live in Trees. Two of the children were diagnosed with developmental delays, and…

Mapping carbon storage in urban trees with multi-source remote sensing data: Relationships between biomass, land use, and demographics in Boston neighborhoods

International Nuclear Information System (INIS)

Raciti, Steve M.; Hutyra, Lucy R.; Newell, Jared D.

2014-01-01

High resolution maps of urban vegetation and biomass are powerful tools for policy-makers and community groups seeking to reduce rates of urban runoff, moderate urban heat island effects, and mitigate the effects of greenhouse gas emissions. We developed a very high resolution map of urban tree biomass, assessed the scale sensitivities in biomass estimation, compared our results with lower resolution estimates, and explored the demographic relationships in biomass distribution across the City of Boston. We integrated remote sensing data (including LiDAR-based tree height estimates) and field-based observations to map canopy cover and aboveground tree carbon storage at ∼ 1 m spatial scale. Mean tree canopy cover was estimated to be 25.5 ± 1.5% and carbon storage was 355 Gg (28.8 Mg C ha −1 ) for the City of Boston. Tree biomass was highest in forest patches (110.7 Mg C ha −1 ), but residential (32.8 Mg C ha −1 ) and developed open (23.5 Mg C ha −1 ) land uses also contained relatively high carbon stocks. In contrast with previous studies, we did not find significant correlations between tree biomass and the demographic characteristics of Boston neighborhoods, including income, education, race, or population density. The proportion of households that rent was negatively correlated with urban tree biomass (R 2 = 0.26, p = 0.04) and correlated with Priority Planting Index values (R 2 = 0.55, p = 0.001), potentially reflecting differences in land management among rented and owner-occupied residential properties. We compared our very high resolution biomass map to lower resolution biomass products from other sources and found that those products consistently underestimated biomass within urban areas. This underestimation became more severe as spatial resolution decreased. This research demonstrates that 1) urban areas contain considerable tree carbon stocks; 2) canopy cover and biomass may not be related to the demographic characteristics of Boston

Sustainable Urban Fringes - Connecting Urban and Rural : Final report of the SURF project

NARCIS (Netherlands)

Bruijn, de T.J.N.M. (Theo); Haccoû, H.A. (Huib); Leslie, A. (Allison); Lier, G. (Goos); Littlewood, S. (Stephan); Oldejans, R. (Rolf); Thomas, K. (Kevin); Vries, de B.J. (Bauke); Watt, E. (Emma); Wishardt, M. (Michelle)

2012-01-01

What happens at the urban edge and the SURF aspiration to influence it? Projects in the urban fringe Urban fringe governance Integrated policy guidelines and approaches towards urban fringe planning and management The future management of the urban fringe

Market-Based Approaches toward the Development of Urban Forest Carbon Projects in the United States

Science.gov (United States)

Neelam C. Poudyal; Jacek P. Siry; J. M. Bowker

2012-01-01

The United States has observed unprecedented urban growth over the last few decades. Nowak et al. (2005) noted that between 1990 and 2000, the share of urban land area in the nation increased from 2.5% to 3.1%. Existing urban areas in the U.S. maintain average tree coverage of 27% (Nowak et al. 2001), and consist of millions of trees along streets and in parks,...

The evolution of Wisconsin's urban FIA program—yesterday today and tomorrow

Science.gov (United States)

Andrew M. Stoltman; Richard B. Rideout

2015-01-01

In 2002, Wisconsin was part of two pilot projects in cooperation with the US Forest Service. The first was a street tree assessment, and the second was an urban FIA project. The data generated by these pilots changed the way that Wisconsin DNRs’ Urban Forestry Program conducts its business. Although there have been several urban FIA pilot projects throughout the U.S.,...

Physical Characters of Trees And Their Effects on Micro-Climate (Case Study at Urban Forest and Green Open Space at Semarang City

Directory of Open Access Journals (Sweden)

Endes N Dahlan

2016-08-01

Full Text Available Air temperature in cities are increasing which can cause reduce the human comfort and productivity. Urban forest can make the environment comfortable. The objectiveof the researc hwere: (1. To Determine the effects of urban forest on air temperature and relative humidity, (2. To analyze the effects of physical characters of trees ont he micro-climate amelioration and(3. To Determine species of trees which are very effective for micro-climate amelioration.The results of the research revealed that the average of daily air temperature in the urban forest was 30.2 C with arelative humidityof 74.0%, while the daily air temperature around the urban forest was 31.8 Karakter Fisik Pohon ... (Dahlan E o C with relative humidityof 71.1%. Tree composisitin of all study sites consist of192trees, 29 speciesand 13families. The TinjomoyoForest Tourism has the highest density of trees(406trees/ha, while the lowest in the Parks Minister Supeno (316trees/ha. Value of Key Performance Indicator (KPI of trees based on calculation of tall of trees, diameter of canopies, total leaves area and canopy forms noticed that very effective trees for micro-climate amelioration were: Angsana(Pterocarpus indicus, beringin(Ficus benjamina, flamboyan(Delonix regia , ketapang(Terminalia catappa, mahoni (Swietenia mahogany, andtrembesi (Albizia saman.

US Urban Forest Statistics, Values, and Projections

Science.gov (United States)

David J Nowak; Eric J. Greenfield

2018-01-01

U.S. urban land increased from 2.6% (57.9 million acres) in 2000 to 3.0% (68.0 million acres) in 2010. States with the greatest amount of urban growth were in the South/Southeast (TX, FL, NC, GA and SC). Between 2010 and 2060, urban land is projected to increase another 95.5 million acres to 163.1 million acres (8.6%) with 18 states projected to have an increase of...

Landscaping Considerations for Urban Stream Restoration Projects

National Research Council Canada - National Science Library

Bailey, Pam

2004-01-01

... after restoration and its functionality for public use. The landscaping component of such stream and riparian restoration projects must be emphasized given its importance of visual success and public perception. The purpose of this technical note is to address landscaping considerations associated with urban stream and riparian restoration projects, and provide ideas to managers for enhancing the visual appeal and aesthetic qualities of urban projects.

Trees in urban street canyons and their impact on the dispersion of automobile exhausts

OpenAIRE

Gromke, Christof; Ruck, Bodo

2007-01-01

The aim of the present study is to clarify the influence of trees on the dispersion of automobile exhausts in urban street canyons. For this purpose, measurements have been performed with a small scale wind tunnel model of an idealized, isolated street canyon with model trees placed along the canyon center axis. Sulfur hexafluoride (SF6) was released from a line source embedded in the street surface, simulating vehicle exhaust emissions. The influence of various tree planting arrangements on ...

Contribution of flowering trees to urban atmospheric biogenic volatile organic compound emissions

Science.gov (United States)

Baghi, R.; Helmig, D.; Guenther, A.; Duhl, T.; Daly, R.

2012-10-01

Emissions of biogenic volatile organic compounds (BVOC) from urban trees during and after blooming were measured during spring and early summer 2009 in Boulder, Colorado. Air samples were collected onto solid adsorbent cartridges from branch enclosures on the tree species crabapple (Malus sp.), horse chestnut (Aesculus carnea, "Ft. McNair"), honey locust (Gleditsia triacanthos, "Sunburst"), and hawthorn (Crataegus laevigata, "Pauls Scarlet"). These species constitute ~ 65% of the insect-pollinated fraction of the flowering tree canopy (excluding catkin-producing trees) from the street area managed by the City of Boulder. Samples were analyzed for C10-C15 BVOC by thermal desorption and gas chromatography coupled to a flame ionization detector and a mass spectrometer (GC/FID/MS). Identified emissions and emission rates from these four tree species during the flowering phase were found to vary over a wide range. Monoterpene emissions were identified for honey locust, horse chestnut and hawthorn. Sesquiterpene emissions were observed in horse chestnut and hawthorn samples. Crabapple flowers were found to emit significant amounts of benzyl alcohol and benzaldehyde. Floral BVOC emissions increased with temperature, generally exhibiting exponential temperature dependence. Changes in BVOC speciation during and after the flowering period were observed for every tree studied. Emission rates were significantly higher during the blooming compared to the post-blooming state for crabapple and honey locust. The results were scaled to the dry mass of leaves and flowers contained in the enclosure. Only flower dry mass was accounted for crabapple emission rates as leaves appeared at the end of the flowering period. Total normalized (30 °C) monoterpene emissions from honey locust were higher during flowering (5.3 μgC g-1 h-1) than after flowering (1.2 μgC g-1 h-1). The total normalized BVOC emission rate from crabapple (93 μgC g-1 h-1) during the flowering period is of the same

Treatment of suspended solids and heavy metals from urban stormwater runoff by a tree box filter.

Science.gov (United States)

Geronimo, F K F; Maniquiz-Redillas, M C; Tobio, J A S; Kim, L H

2014-01-01

Particulates, inorganic and toxic constituents are the most common pollutants associated with urban stormwater runoff. Heavy metals such as chromium, nickel, copper, zinc, cadmium and lead are found to be in high concentration on paved roads or parking lots due to vehicle emissions. In order to control the rapid increase of pollutant loads in stormwater runoff, the Korean Ministry of Environment proposed the utilization of low impact developments. One of these was the application of tree box filters that act as a bioretention treatment system which executes filtration and sorption processes. In this study, a tree box filter located adjacent to an impervious parking lot was developed to treat suspended solids and heavy metal concentrations from urban stormwater runoff. In total, 11 storm events were monitored from July 2010 to August 2012. The results showed that the tree box filter was highly effective in removing particulates (up to 95%) and heavy metals (at least 70%) from the urban stormwater runoff. Furthermore, the tree box filter was capable of reducing the volume runoff by 40% at a hydraulic loading rate of 1 m/day and below.

Mapping carbon storage in urban trees with multi-source remote sensing data: Relationships between biomass, land use, and demographics in Boston neighborhoods

Energy Technology Data Exchange (ETDEWEB)

Raciti, Steve M., E-mail: Steve.M.Raciti@Hofstra.edu [Department of Biology, Hofstra University, Gittleson Hall, Hempstead, NY 11549 (United States); Department of Earth and Environment, Boston University, 685 Commonwealth Ave., Boston, MA 02215 (United States); Hutyra, Lucy R.; Newell, Jared D. [Department of Earth and Environment, Boston University, 685 Commonwealth Ave., Boston, MA 02215 (United States)

2014-12-01

High resolution maps of urban vegetation and biomass are powerful tools for policy-makers and community groups seeking to reduce rates of urban runoff, moderate urban heat island effects, and mitigate the effects of greenhouse gas emissions. We developed a very high resolution map of urban tree biomass, assessed the scale sensitivities in biomass estimation, compared our results with lower resolution estimates, and explored the demographic relationships in biomass distribution across the City of Boston. We integrated remote sensing data (including LiDAR-based tree height estimates) and field-based observations to map canopy cover and aboveground tree carbon storage at ∼ 1 m spatial scale. Mean tree canopy cover was estimated to be 25.5 ± 1.5% and carbon storage was 355 Gg (28.8 Mg C ha{sup −1}) for the City of Boston. Tree biomass was highest in forest patches (110.7 Mg C ha{sup −1}), but residential (32.8 Mg C ha{sup −1}) and developed open (23.5 Mg C ha{sup −1}) land uses also contained relatively high carbon stocks. In contrast with previous studies, we did not find significant correlations between tree biomass and the demographic characteristics of Boston neighborhoods, including income, education, race, or population density. The proportion of households that rent was negatively correlated with urban tree biomass (R{sup 2} = 0.26, p = 0.04) and correlated with Priority Planting Index values (R{sup 2} = 0.55, p = 0.001), potentially reflecting differences in land management among rented and owner-occupied residential properties. We compared our very high resolution biomass map to lower resolution biomass products from other sources and found that those products consistently underestimated biomass within urban areas. This underestimation became more severe as spatial resolution decreased. This research demonstrates that 1) urban areas contain considerable tree carbon stocks; 2) canopy cover and biomass may not be related to the demographic

VOXEL-BASED APPROACH FOR ESTIMATING URBAN TREE VOLUME FROM TERRESTRIAL LASER SCANNING DATA

Directory of Open Access Journals (Sweden)

C. Vonderach

2012-07-01

Full Text Available The importance of single trees and the determination of related parameters has been recognized in recent years, e.g. for forest inventories or management. For urban areas an increasing interest in the data acquisition of trees can be observed concerning aspects like urban climate, CO2 balance, and environmental protection. Urban trees differ significantly from natural systems with regard to the site conditions (e.g. technogenic soils, contaminants, lower groundwater level, regular disturbance, climate (increased temperature, reduced humidity and species composition and arrangement (habitus and health status and therefore allometric relations cannot be transferred from natural sites to urban areas. To overcome this problem an extended approach was developed for a fast and non-destructive extraction of branch volume, DBH (diameter at breast height and height of single trees from point clouds of terrestrial laser scanning (TLS. For data acquisition, the trees were scanned with highest scan resolution from several (up to five positions located around the tree. The resulting point clouds (20 to 60 million points are analysed with an algorithm based on voxel (volume elements structure, leading to an appropriate data reduction. In a first step, two kinds of noise reduction are carried out: the elimination of isolated voxels as well as voxels with marginal point density. To obtain correct volume estimates, the voxels inside the stem and branches (interior voxels where voxels contain no laser points must be regarded. For this filling process, an easy and robust approach was developed based on a layer-wise (horizontal layers of the voxel structure intersection of four orthogonal viewing directions. However, this procedure also generates several erroneous "phantom" voxels, which have to be eliminated. For this purpose the previous approach was extended by a special region growing algorithm. In a final step the volume is determined layer-wise based on the

Tree Mortality Undercuts Ability of Tree-Planting Programs to Provide Benefits: Results of a Three-City Study

Directory of Open Access Journals (Sweden)

Sarah Widney

2016-03-01

Full Text Available Trees provide numerous benefits for urban residents, including reduced energy usage, improved air quality, stormwater management, carbon sequestration, and increased property values. Quantifying these benefits can help justify the costs of planting trees. In this paper, we use i-Tree Streets to quantify the benefits of street trees planted by nonprofits in three U.S. cities (Detroit, Michigan; Indianapolis, Indiana, and Philadelphia, Pennsylvania from 2009 to 2011. We also use both measured and modeled survival and growth rates to “grow” the tree populations 5 and 10 years into the future to project the future benefits of the trees under different survival and growth scenarios. The 4059 re-inventoried trees (2864 of which are living currently provide almost $40,000 (USD in estimated annual benefits ($9–$20/tree depending on the city, the majority (75% of which are increased property values. The trees can be expected to provide increasing annual benefits during the 10 years after planting if the annual survival rate is higher than the 93% annual survival measured during the establishment period. However, our projections show that with continued 93% or lower annual survival, the increase in annual benefits from tree growth will not be able to make up for the loss of benefits as trees die. This means that estimated total annual benefits from a cohort of planted trees will decrease between the 5-year projection and the 10-year projection. The results of this study indicate that without early intervention to ensure survival of planted street trees, tree mortality may be significantly undercutting the ability of tree-planting programs to provide benefits to neighborhood residents.

Growing the urban forest: tree performance in response to biotic and abiotic land management

Science.gov (United States)

Emily E. Oldfield; Alexander J. Felson; D. S. Novem Auyeung; Thomas W. Crowther; Nancy F. Sonti; Yoshiki Harada; Daniel S. Maynard; Noah W. Sokol; Mark S. Ashton; Robert J. Warren; Richard A. Hallett; Mark A. Bradford

2015-01-01

Forests are vital components of the urban landscape because they provide ecosystem services such as carbon sequestration, storm-water mitigation, and air-quality improvement. To enhance these services, cities are investing in programs to create urban forests. A major unknown, however, is whether planted trees will grow into the mature, closed-canopied forest on which...

The Tree of Life Project

Science.gov (United States)

Milbrath, Sherry

2009-01-01

Middle-school students are just beginning to recognize their place in the world. That is why this author believes it is important to incorporate their world into their art. In this article, the author discusses the "Tree of Life" project, which she developed for her students in order to make them aware of various environmental issues, and how to…

Evaluation of impacts of trees on PM2.5 dispersion in urban streets

Science.gov (United States)

Jin, Sijia; Guo, Jiankang; Wheeler, Stephen; Kan, Liyan; Che, Shengquan

2014-12-01

Reducing airborne particulate matter (PM), especially PM2.5 (PM with aerodynamic diameters of 2.5 μm or less), in urban street canyons is critical to the health of central city population. Tree-planting in urban street canyons is a double-edged sword, providing landscape benefits while inevitably resulting in PM2.5 concentrating at street level, thus showing negative environmental effects. Thereby, it is necessary to quantify the impact of trees on PM2.5 dispersion and obtain the optimum structure of street trees for minimizing the PM2.5 concentration in street canyons. However, most of the previous findings in this field were derived from wind tunnel or numerical simulation rather than on-site measuring data. In this study, a seasonal investigation was performed in six typical street canyons in the residential area of central Shanghai, which has been suffering from haze pollution while having large numbers of green streets. We monitored and measured PM2.5 concentrations at five heights, structural parameters of street trees and weather. For tree-free street canyons, declining PM2.5 concentrations were found with increasing height. However, in presence of trees the reduction rate of PM2.5 concentrations was less pronounced, and for some cases, the concentrations even increased at the top of street canyons, indicating tree canopies are trapping PM2.5. To quantify the decrease of PM2.5 reduction rate, we developed the attenuation coefficient of PM2.5 (PMAC). The wind speed was significantly lower in street canyons with trees than in tree-free ones. A mixed-effects model indicated that canopy density (CD), leaf area index (LAI), rate of change of wind speed were the most significant predictors influencing PMAC. Further regression analysis showed that in order to balance both environmental and landscape benefits of green streets, the optimum range of CD and LAI was 50%-60% and 1.5-2.0 respectively. We concluded by suggesting an optimized tree-planting pattern and

PIXE analysis of tree leaves as a possible comparative integral monitor of particulates in urban areas

International Nuclear Information System (INIS)

Zucchiati, A.; Annegarm, H.J.; Chisci, R.

1988-01-01

The possibility of obtaing integral comparative data for particulate distribution in urban areas from PIXE analysis of tree leaves is discussed in relation to the leaf gross anatomy, to the diffusion of selected tree species in such areas and to the implementation of experimental techniques necessary to make PIXE analysis effective. Multielemental scans were performed on a small set samples; results are compared to PIXE analysis of typical urban aerosols. The validity of the method and the criteria for yearly relative comparisons of different areas are discissed

Trees in urban parks and forests reduce O3, but not NO2 concentrations in Baltimore, MD, USA

Science.gov (United States)

Yli-Pelkonen, Vesa; Scott, Anna A.; Viippola, Viljami; Setälä, Heikki

2017-10-01

Trees and other vegetation absorb and capture air pollutants, leading to the common perception that they, and trees in particular, can improve air quality in cities and provide an important ecosystem service for urban inhabitants. Yet, there has been a lack of empirical evidence showing this at the local scale with different plant configurations and climatic regions. We studied the impact of urban park and forest vegetation on the levels of nitrogen dioxide (NO2) and ground-level ozone (O3) while controlling for temperature during early summer (May) using passive samplers in Baltimore, USA. Concentrations of O3 were significantly lower in tree-covered habitats than in adjacent open habitats, but concentrations of NO2 did not differ significantly between tree-covered and open habitats. Higher temperatures resulted in higher pollutant concentrations and NO2 and O3 concentration were negatively correlated with each other. Our results suggest that the role of trees in reducing NO2 concentrations in urban parks and forests in the Mid-Atlantic USA is minor, but that the presence of tree-cover can result in lower O3 levels compared to similar open areas. Our results further suggest that actions aiming at local air pollution mitigation should consider local variability in vegetation, climate, micro-climate, and traffic conditions.

Tree-crown-resolving large-eddy simulation for evaluating greenery effects on urban heat environments

Science.gov (United States)

Matsuda, K.; Onishi, R.; Takahashi, K.

2017-12-01

Urban high temperatures due to the combined influence of global warming and urban heat islands increase the risk of heat stroke. Greenery is one of possible countermeasures for mitigating the heat environments since the transpiration and shading effect of trees can reduce the air temperature and the radiative heat flux. In order to formulate effective measures, it is important to estimate the influence of the greenery on the heat stroke risk. In this study, we have developed a tree-crown-resolving large-eddy simulation (LES) model that is coupled with three-dimensional radiative transfer (3DRT) model. The Multi-Scale Simulator for the Geoenvironment (MSSG) is used for performing building- and tree-crown-resolving LES. The 3DRT model is implemented in the MSSG so that the 3DRT is calculated repeatedly during the time integration of the LES. We have confirmed that the computational time for the 3DRT model is negligibly small compared with that for the LES and the accuracy of the 3DRT model is sufficiently high to evaluate the radiative heat flux at the pedestrian level. The present model is applied to the analysis of the heat environment in an actual urban area around the Tokyo Bay area, covering 8 km × 8 km with 5-m grid mesh, in order to confirm its feasibility. The results show that the wet-bulb globe temperature (WBGT), which is an indicator of the heat stroke risk, is predicted in a sufficiently high accuracy to evaluate the influence of tree crowns on the heat environment. In addition, by comparing with a case without the greenery in the Tokyo Bay area, we have confirmed that the greenery increases the low WBGT areas in major pedestrian spaces by a factor of 3.4. This indicates that the present model can predict the greenery effect on the urban heat environment quantitatively.

Mapping carbon storage in urban trees with multi-source remote sensing data: relationships between biomass, land use, and demographics in Boston neighborhoods.

Science.gov (United States)

Raciti, Steve M; Hutyra, Lucy R; Newell, Jared D

2014-12-01

High resolution maps of urban vegetation and biomass are powerful tools for policy-makers and community groups seeking to reduce rates of urban runoff, moderate urban heat island effects, and mitigate the effects of greenhouse gas emissions. We developed a very high resolution map of urban tree biomass, assessed the scale sensitivities in biomass estimation, compared our results with lower resolution estimates, and explored the demographic relationships in biomass distribution across the City of Boston. We integrated remote sensing data (including LiDAR-based tree height estimates) and field-based observations to map canopy cover and aboveground tree carbon storage at ~1m spatial scale. Mean tree canopy cover was estimated to be 25.5±1.5% and carbon storage was 355Gg (28.8MgCha(-1)) for the City of Boston. Tree biomass was highest in forest patches (110.7MgCha(-1)), but residential (32.8MgCha(-1)) and developed open (23.5MgCha(-1)) land uses also contained relatively high carbon stocks. In contrast with previous studies, we did not find significant correlations between tree biomass and the demographic characteristics of Boston neighborhoods, including income, education, race, or population density. The proportion of households that rent was negatively correlated with urban tree biomass (R(2)=0.26, p=0.04) and correlated with Priority Planting Index values (R(2)=0.55, p=0.001), potentially reflecting differences in land management among rented and owner-occupied residential properties. We compared our very high resolution biomass map to lower resolution biomass products from other sources and found that those products consistently underestimated biomass within urban areas. This underestimation became more severe as spatial resolution decreased. This research demonstrates that 1) urban areas contain considerable tree carbon stocks; 2) canopy cover and biomass may not be related to the demographic characteristics of Boston neighborhoods; and 3) that recent advances

Mapping Carbon Storage in Urban Trees with Multi-source Remote Sensing Data: Relationships between Biomass, Land Use, and Demographics in Boston Neighborhoods

Science.gov (United States)

Raciti, S. M.; Hutyra, L.

2014-12-01

High resolution maps of urban vegetation and biomass are powerful tools for policy-makers and community groups seeking to reduce rates of urban runoff, moderate urban heat island effects, and mitigate the effects of greenhouse gas emissions. We develop a very high resolution map of urban tree biomass, assess the scale sensitivities in biomass estimation, compare our results with lower resolution estimates, and explore the demographic relationships in biomass distribution across the City of Boston. We integrated remote sensing data (including LiDAR-based tree height estimates) and field-based observations to map canopy cover and aboveground tree carbon storage at ~1 m spatial scale. Mean tree canopy cover was estimated to be 25.5±1.5% and carbon storage was 355 Gg (28.8 Mg C ha-1) for the City of Boston. Tree biomass was highest in forest patches (110.7 Mg C ha-1), but residential (32.8 Mg C ha-1) and developed open (23.5 Mg C ha-1) land uses also contained relatively high carbon stocks. In contrast with previous studies, we did not find significant correlations between tree biomass and the demographic characteristics of Boston neighborhoods, including income, education, race, or population density. The proportion of households that rent was negatively correlated with urban tree biomass (R2=0.26, p=0.04) and correlated with Priority Planting Index values (R2=0.55, p=0.001), potentially reflecting differences in land management among rented and owner-occupied residential properties. We compared our very high resolution biomass map to lower resolution biomass products from other sources and found that those products consistently underestimated biomass within urban areas. This underestimation became more severe as spatial resolution decreased. This research demonstrates that 1) urban areas contain considerable tree carbon stocks; 2) canopy cover and biomass may not be related to the demographic characteristics of Boston neighborhoods; and 3) that recent advances in

The Iqmulus Urban Showcase: Automatic Tree Classification and Identification in Huge Mobile Mapping Point Clouds

Science.gov (United States)

Böhm, J.; Bredif, M.; Gierlinger, T.; Krämer, M.; Lindenberg, R.; Liu, K.; Michel, F.; Sirmacek, B.

2016-06-01

Current 3D data capturing as implemented on for example airborne or mobile laser scanning systems is able to efficiently sample the surface of a city by billions of unselective points during one working day. What is still difficult is to extract and visualize meaningful information hidden in these point clouds with the same efficiency. This is where the FP7 IQmulus project enters the scene. IQmulus is an interactive facility for processing and visualizing big spatial data. In this study the potential of IQmulus is demonstrated on a laser mobile mapping point cloud of 1 billion points sampling ~ 10 km of street environment in Toulouse, France. After the data is uploaded to the IQmulus Hadoop Distributed File System, a workflow is defined by the user consisting of retiling the data followed by a PCA driven local dimensionality analysis, which runs efficiently on the IQmulus cloud facility using a Spark implementation. Points scattering in 3 directions are clustered in the tree class, and are separated next into individual trees. Five hours of processing at the 12 node computing cluster results in the automatic identification of 4000+ urban trees. Visualization of the results in the IQmulus fat client helps users to appreciate the results, and developers to identify remaining flaws in the processing workflow.

Urban tree growth modeling

Science.gov (United States)

E. Gregory McPherson; Paula J. Peper

2012-01-01

This paper describes three long-term tree growth studies conducted to evaluate tree performance because repeated measurements of the same trees produce critical data for growth model calibration and validation. Several empirical and process-based approaches to modeling tree growth are reviewed. Modeling is more advanced in the fields of forestry and...

The effect of urban trees on the rental price of single-family homes in Portland, Oregon

Science.gov (United States)

Geoffrey H. Donovan; David T. Butry

2011-01-01

Few studies have estimated the effect of environmental amenities on the rental price of houses. We address this gap in the literature by quantifying the effect of urban trees on the rental price of single-family homes in Portland, Oregon, USA. We found that an additional tree on a house's lot increased monthly rent by $5.62, and a tree in the public right of way...

Local Level Stormwater Harvesting and Reuse: A Practical Solution to the Water Security Challenges Faced by Urban Trees

Directory of Open Access Journals (Sweden)

Peter W. B. Nichols

2015-07-01

Full Text Available Water Sensitive Urban Design (WSUD treatment devices are often used to restore natural drainage properties in developed catchments. WSUD can make positive contributions to the restoration of natural ecosystem processes, by supporting trees and habitats in urban areas without taking up limited urban space. This paper reports on the development and testing of a new WSUD device, the Wicking Tank. It is designed to supply sufficient volumes of water to urban trees through periods of drought via synthetic wicks from an underground storage tank to support adequate tree health. Relying on gravity fed stormwater, and the natural capillarity, adhesion, and cohesion properties of water and the process of hydraulic redistribution, water is transferred from the tank and into the rhizosphere of the tree. Water demand is controlled passively by the water potential differential across the root zone. Proof of concept testing of the Wicking Tank has shown the device to successfully draw water into soil to support the ongoing survival of a potted plant for over 20 weeks. Substantial differences are anticipated between this proof of concept test and an in-situ field trial. A field-based demonstration style version of the Wicking Tank is planned for construction and testing in 2015.

A life cycle greenhouse gas inventory of a tree production system

Science.gov (United States)

Alissa Kendall; E. Gregory McPherson

2012-01-01

PurposeThis study provides a detailed, process-based life cycle greenhouse gas (GHG) inventory of an ornamental tree production system for urban forestry. The success of large-scale tree planting initiatives for climate protection depends on projects being net sinks for CO2 over their entire life cycle....

Use of GLM approach to assess the responses of tropical trees to urban air pollution in relation to leaf functional traits and tree characteristics.

Science.gov (United States)

Mukherjee, Arideep; Agrawal, Madhoolika

2018-05-15

Responses of urban vegetation to air pollution stress in relation to their tolerance and sensitivity have been extensively studied, however, studies related to air pollution responses based on different leaf functional traits and tree characteristics are limited. In this paper, we have tried to assess combined and individual effects of major air pollutants PM 10 (particulate matter ≤ 10 µm), TSP (total suspended particulate matter), SO 2 (sulphur dioxide), NO 2 (nitrogen dioxide) and O 3 (ozone) on thirteen tropical tree species in relation to fifteen leaf functional traits and different tree characteristics. Stepwise linear regression a general linear modelling approach was used to quantify the pollution response of trees against air pollutants. The study was performed for six successive seasons for two years in three distinct urban areas (traffic, industrial and residential) of Varanasi city in India. At all the study sites, concentrations of air pollutants, specifically PM (particulate matter) and NO 2 were above the specified standards. Distinct variations were recorded in all the fifteen leaf functional traits with pollution load. Caesalpinia sappan was identified as most tolerant species followed by Psidium guajava, Dalbergia sissoo and Albizia lebbeck. Stepwise regression analysis identified maximum response of Eucalyptus citriodora and P. guajava to air pollutants explaining overall 59% and 58% variability's in leaf functional traits, respectively. Among leaf functional traits, maximum effect of air pollutants was observed on non-enzymatic antioxidants followed by photosynthetic pigments and leaf water status. Among the pollutants, PM was identified as the major stress factor followed by O 3 explaining 47% and 33% variability's in leaf functional traits. Tolerance and pollution response were regulated by different tree characteristics such as height, canopy size, leaf from, texture and nature of tree. Outcomes of this study will help in urban forest

Elevated Levels of Herbivory in Urban Landscapes: Are Declines in Tree Health More Than an Edge Effect?

Directory of Open Access Journals (Sweden)

Fiona J. Christie

2005-06-01

Full Text Available Urbanization is one of the most extreme and rapidly growing anthropogenic pressures on the natural world. Urban development has led to substantial fragmentation of areas of natural habitat, resulting in significant impacts on biodiversity and disruptions to ecological processes. We investigated the levels of leaf damage caused by invertebrates in a dominant canopy species in urban remnants in a highly fragmented urban landscape in Sydney, Australia, by assessing the frequency and extent of chewing and surface damage of leaves in urban remnants compared to the edges and interiors of continuous areas of vegetation. Although no difference was detected in the frequency of leaves showing signs of damage at small, edge, and interior sites, small sites suffered significantly greater levels of leaf damage than did interior sites. Trees at edge sites showed intermediate levels of damage, suggesting that edge effects alone are not the cause of higher levels of herbivory. These findings are the first to demonstrate the effects of urbanization on invertebrate damage in dominant trees at coarse scales. This is consistent with hypotheses predicting that changes in species composition through urban fragmentation affect ecological interactions.

Radiocarbon Records of Fossil Fuel Emissions From Urban Trees in the Greater Salt Lake Valley From Mid-Century to Present.

Science.gov (United States)

Chritz, K.; Buchert, M.; Walker, J. C.; Mendoza, D.; Pataki, D. E.; Xu, X.; Lin, J. C.

2017-12-01

Generating long term records of fossil fuel emissions of urban environments is complicated by the fact that direct observations of emissions and urban atmospheric CO2 concentrations were only collected in the recent past. Radiocarbon (14C) in tree rings from urban trees can provide archives of fossil fuel emissions that may track population growth over time, as higher population density is typically correlated with increased vehicular traffic and associated CO2 emissions, which are radiocarbon dead. We present radiocarbon measurements (n=125) from five roadside green ash trees (Fraxinus pennsylvanica) located in three cities of northern Utah - Salt Lake City (urban, 2016 population: 193,744), Logan City (agricultural, 2016 population: 49,110) and Heber (rural, 2016 population: 14,969). Urban trees were cored in four cardinal directions and ring widths were measured and counted to establish a chronology. One ring from every third year in a single core from each tree was removed and holocellulose was extracted from bulk wood of individual rings for 14C analysis. Fraction CO2 from fossil fuel burning (CO2-ff) was calculated using a simple mass-balance calculation from measured 14C values and remote background atmospheric 14CO2 values for NH Zone 2. The data from all three cities indicate a general trend of increasing CO2-ff uptake by the trees from 1980s to present, as expected with increased population growth and vehicular traffic. However, records in all three cities show unique elevated CO2-ff prior to the 1980s, assuming similar climate patterns through time, diverging from historic population size. We employed atmospheric simulations from the STILT (Stochastic Time-Inverted Lagrangian Transport) models for each of these trees to create footprints to determine source areas for CO2. These footprints reveal that atmospheric sampling areas can be large for certain trees, and other sources of 14C dead carbon, such as coal and natural gas from industrial emissions

Toward a predictive model for water and carbon fluxes of non-native trees in urban habitats

Science.gov (United States)

McCarthy, H. R.; Jenerette, G. D.; Pataki, D. E.

2008-12-01

There is considerable interest in estimating uptake of water and carbon by urban trees, in order to assess some of the major costs and benefits associated with maintaining or expanding urban tree cover. However, making large-scale estimates of water and carbon fluxes is challenging in urban ecosystems, where community composition and environmental conditions are highly altered and experimental data is sparse. This is particularly true in regions such as southern California, where few trees are native, yet many species can flourish given supplemental irrigation. In such scenarios one practical way to scale water and carbon fluxes may be to identify reliable traits which can be used to predict gas exchange when trees are transplanted to a new environment. To test this approach, leaf level gas exchange measurements were conducted on eight common urban tree species within the Los Angeles basin. The objective was to determine how well gas exchange parameters, including maximum photosynthesis and stomatal conductance, sensitivity of stomatal conductance to vapor pressure deficit (VPD), and water use efficiency (WUE), can be predicted based on the native habitat and climate (temperature and precipitation) of each study species. All of the species studied naturally occur in humid tropical or subtropical climate zones where precipitation varies widely from ~400 - 3000 mm per year. We found Jacaranda (Jacaranda chelonia) and honey locust (Gleditsia triacanthos) to have the highest photosynthesis and reference (at VPD=1 kPa) conductance, and to be most sensitive to VPD. WUE was found to be greatest in Indian laurel fig (Ficus microcarpa), rose gum (Eucalyptus grandis) and Queensland lacebark (Brachychiton discolor). The relative ordering of maximum photosynthesis and conductance across species was not entirely predictable based on our current knowledge of the native habitats of each species: several other species had similar native climates to Jacaranda and honey locust, yet

THE IQMULUS URBAN SHOWCASE: AUTOMATIC TREE CLASSIFICATION AND IDENTIFICATION IN HUGE MOBILE MAPPING POINT CLOUDS

Directory of Open Access Journals (Sweden)

J. Böhm

2016-06-01

Full Text Available Current 3D data capturing as implemented on for example airborne or mobile laser scanning systems is able to efficiently sample the surface of a city by billions of unselective points during one working day. What is still difficult is to extract and visualize meaningful information hidden in these point clouds with the same efficiency. This is where the FP7 IQmulus project enters the scene. IQmulus is an interactive facility for processing and visualizing big spatial data. In this study the potential of IQmulus is demonstrated on a laser mobile mapping point cloud of 1 billion points sampling ~ 10 km of street environment in Toulouse, France. After the data is uploaded to the IQmulus Hadoop Distributed File System, a workflow is defined by the user consisting of retiling the data followed by a PCA driven local dimensionality analysis, which runs efficiently on the IQmulus cloud facility using a Spark implementation. Points scattering in 3 directions are clustered in the tree class, and are separated next into individual trees. Five hours of processing at the 12 node computing cluster results in the automatic identification of 4000+ urban trees. Visualization of the results in the IQmulus fat client helps users to appreciate the results, and developers to identify remaining flaws in the processing workflow.

The Association Between Urban Tree Cover and Gun Assault: A Case-Control and Case-Crossover Study.

Science.gov (United States)

Kondo, Michelle C; South, Eugenia C; Branas, Charles C; Richmond, Therese S; Wiebe, Douglas J

2017-08-01

Green space and vegetation may play a protective role against urban violence. We investigated whether being near urban tree cover during outdoor activities was related to being assaulted with a gun. We conducted geographic information systems-assisted interviews with boys and men aged 10-24 years in Philadelphia, Pennsylvania, including 135 patients who had been shot with a firearm and 274 community controls, during 2008-2011. Each subject reported a step-by-step mapped account of where and with whom they traveled over a full day from waking until being assaulted or going to bed. Geocoded path points were overlaid on mapped layers representing tree locations and place-specific characteristics. Conditional logistic regressions were used to compare case subjects versus controls (case-control) and case subjects at the time of injury versus times earlier that day (case-crossover). When comparing cases at the time of assault to controls matched at the same time of day, being under tree cover was inversely associated with gunshot assault (odds ratio (OR) = 0.70, 95% confidence interval (CI): 0.55, 0.88), especially in low-income areas (OR = 0.69, 95% CI: 0.54, 0.87). Case-crossover models confirmed this inverse association overall (OR = 0.55, 95% CI: 0.34, 0.89) and in low-income areas (OR = 0.54, 95% CI: 0.33, 0.88). Urban greening and tree cover may hold promise as proactive strategies to decrease urban violence. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Quantifying and Mapping the Supply of and Demand for Carbon Storage and Sequestration Service from Urban Trees

Science.gov (United States)

Zhao, Chang; Sander, Heather A.

2015-01-01

Studies that assess the distribution of benefits provided by ecosystem services across urban areas are increasingly common. Nevertheless, current knowledge of both the supply and demand sides of ecosystem services remains limited, leaving a gap in our understanding of balance between ecosystem service supply and demand that restricts our ability to assess and manage these services. The present study seeks to fill this gap by developing and applying an integrated approach to quantifying the supply and demand of a key ecosystem service, carbon storage and sequestration, at the local level. This approach follows three basic steps: (1) quantifying and mapping service supply based upon Light Detection and Ranging (LiDAR) processing and allometric models, (2) quantifying and mapping demand for carbon sequestration using an indicator based on local anthropogenic CO2 emissions, and (3) mapping a supply-to-demand ratio. We illustrate this approach using a portion of the Twin Cities Metropolitan Area of Minnesota, USA. Our results indicate that 1735.69 million kg carbon are stored by urban trees in our study area. Annually, 33.43 million kg carbon are sequestered by trees, whereas 3087.60 million kg carbon are emitted by human sources. Thus, carbon sequestration service provided by urban trees in the study location play a minor role in combating climate change, offsetting approximately 1% of local anthropogenic carbon emissions per year, although avoided emissions via storage in trees are substantial. Our supply-to-demand ratio map provides insight into the balance between carbon sequestration supply in urban trees and demand for such sequestration at the local level, pinpointing critical locations where higher levels of supply and demand exist. Such a ratio map could help planners and policy makers to assess and manage the supply of and demand for carbon sequestration. PMID:26317530

Quantifying and Mapping the Supply of and Demand for Carbon Storage and Sequestration Service from Urban Trees.

Science.gov (United States)

Zhao, Chang; Sander, Heather A

2015-01-01

Studies that assess the distribution of benefits provided by ecosystem services across urban areas are increasingly common. Nevertheless, current knowledge of both the supply and demand sides of ecosystem services remains limited, leaving a gap in our understanding of balance between ecosystem service supply and demand that restricts our ability to assess and manage these services. The present study seeks to fill this gap by developing and applying an integrated approach to quantifying the supply and demand of a key ecosystem service, carbon storage and sequestration, at the local level. This approach follows three basic steps: (1) quantifying and mapping service supply based upon Light Detection and Ranging (LiDAR) processing and allometric models, (2) quantifying and mapping demand for carbon sequestration using an indicator based on local anthropogenic CO2 emissions, and (3) mapping a supply-to-demand ratio. We illustrate this approach using a portion of the Twin Cities Metropolitan Area of Minnesota, USA. Our results indicate that 1735.69 million kg carbon are stored by urban trees in our study area. Annually, 33.43 million kg carbon are sequestered by trees, whereas 3087.60 million kg carbon are emitted by human sources. Thus, carbon sequestration service provided by urban trees in the study location play a minor role in combating climate change, offsetting approximately 1% of local anthropogenic carbon emissions per year, although avoided emissions via storage in trees are substantial. Our supply-to-demand ratio map provides insight into the balance between carbon sequestration supply in urban trees and demand for such sequestration at the local level, pinpointing critical locations where higher levels of supply and demand exist. Such a ratio map could help planners and policy makers to assess and manage the supply of and demand for carbon sequestration.

Urban forestry and carbon: what the reporting protocol means to you

Science.gov (United States)

E.G. McPherson

2008-01-01

Urban forests have a role to play in reducing levels of carbon dioxide and other greenhouse gases (GHG) in the atmosphere (Abdollahi et al. 2000; Pataki et al. 2006). However, very few tree planting projects have been undertaken because of the uncertainty regarding their performance and permanence. The Urban Forest Project Reporting Protocol was developed to reduce...

Urban trees and light-colored surfaces as a climate change strategy: Results from the US and potential in developing countries

Energy Technology Data Exchange (ETDEWEB)

Akbari, H.; Sathaye, J. [Lawrence Berkeley National Lab., CA (United States)

1996-12-31

This paper discusses the impact of two strategies in an urban environment for effecting substantial energy savings. They are the use of light colored materials on roofing and other flat surfaces, and the planting of additional trees. The lighter colored roofing materials will reflect more solar heat, resulting in lowered air conditioning costs. The additional trees will provide more shading, thereby increasing comfort, and will act as an aid in dropping the ambient temperature by means of evapotranspiration through the leaf systems. Both of these effects will reduce the direct energy inputs leading to air conditioning loads in an urban setting, and indirectly they will have an impact on urban smog though the lowered ambient temperature. The authors also discuss the applications of these ideas in developing countries, where often building energy costs can consume half of developed electrical capacity, and which tend to be in warmer climates. The density of many major urban areas in developing countries make the use of trees much harder to implement.

Applications of urban tree canopy assessment and prioritization tools: supporting collaborative decision making to achieve urban sustainability goals

Science.gov (United States)

Dexter H. Locke; J. Morgan Grove; Michael Galvin; Jarlath P.M. ONeil-Dunne; Charles. Murphy

2013-01-01

Urban Tree Canopy (UTC) Prioritizations can be both a set of geographic analysis tools and a planning process for collaborative decision-making. In this paper, we describe how UTC Prioritizations can be used as a planning process to provide decision support to multiple government agencies, civic groups and private businesses to aid in reaching a canopy target. Linkages...

Urban transportation projects conceptualised:

DEFF Research Database (Denmark)

Pineda, Andres Felipe Valderrama

is straightforward: transportation projects transform cities. The paradoxical reality thus is that a problem that has been traditionally conceptualized in technical terms (transportation engineering, transportation economics, planning theory, traffic engineering, urban planning, etc.), has tremendous consequences...... operation when discussing transportation projects in big cities. The tradition of Science and Technology Studies might have provided some clues. In the following paper we discuss the most prominent aspects of some theories in STS in order to understand and conceptualize the cases of Bogotá and Copenhagen...

Can urban tree roots improve infiltration through compacted subsoils for stormwater management?

Science.gov (United States)

Bartens, Julia; Day, Susan D; Harris, J Roger; Dove, Joseph E; Wynn, Theresa M

2008-01-01

Global land use patterns and increasing pressures on water resources demand creative urban stormwater management. Strategies encouraging infiltration can enhance groundwater recharge and water quality. Urban subsoils are often relatively impermeable, and the construction of many stormwater detention best management practices (D-BMPs) exacerbates this condition. Root paths can act as conduits for water, but this function has not been demonstrated for stormwater BMPs where standing water and dense subsoils create a unique environment. We examined whether tree roots can penetrate compacted subsoils and increase infiltration rates in the context of a novel infiltration BMP (I-BMP). Black oak (Quercus velutina Lam.) and red maple (Acer rubrum L.) trees, and an unplanted control, were installed in cylindrical planting sleeves surrounded by clay loam soil at two compaction levels (bulk density = 1.3 or 1.6 g cm(-3)) in irrigated containers. Roots of both species penetrated the more compacted soil, increasing infiltration rates by an average of 153%. Similarly, green ash (Fraxinus pennsylvanica Marsh.) trees were grown in CUSoil (Amereq Corp., New York) separated from compacted clay loam subsoil (1.6 g cm(-3)) by a geotextile. A drain hole at mid depth in the CUSoil layer mimicked the overflow drain in a stormwater I-BMP thus allowing water to pool above the subsoil. Roots penetrated the geotextile and subsoil and increased average infiltration rate 27-fold compared to unplanted controls. Although high water tables may limit tree rooting depth, some species may be effective tools for increasing water infiltration and enhancing groundwater recharge in this and other I-BMPs (e.g., raingardens and bioswales).

Good Practice Lessons from the Urban Traffic Project, Denmark

DEFF Research Database (Denmark)

Flyvbjerg, Bent

2002-01-01

In 1990, as the first government in the world, the Danish Cabinet approved a national action plan for sustainable transport. In 1992, as part of the implementation of this plan, the Urban Traffic Project was set up with the EPA. The policy situation was one of a state agency trying to motivate...... urban municipalities to work with T&E (transport and environment) integration, i.e. integration of concerns for safety, energy, air quality, noise etc. in urban traffic planning. 50 major urban municipalities participated in the project. The most important lessons to be learned from the project are: (1......) With a fairly modest investment (DKK 150 million in seed money) it has been possible on a voluntary basis to motivate the majority of urban municipalities to work with T&E integration. (2) The top motivating factor for municipalities to participate was a desire for organisational and professional learning. (3...

For An Urban Wikipedia. The Challenges of the Urban Project. Maurizio Carta

Directory of Open Access Journals (Sweden)

Maurizio Carta

2013-07-01

Full Text Available The city is the pre-eminent encyclopedia of the community, a place where all the components of life, its definition and all its reciprocal relationships are found (Harvey 1989.  In the urban century in which we all are immersed goes from the encyclopedia to the urban Wikipedia: that is a collective, cognitive project in which the inhabitants and the operators, the decision-makers and the participants, the project makers and the actors make up the structure, continually enriching it with the change of practices, with the interpretation of its meanings and intentions. In order to make, understand, represent and transmit the urban Wikipedia, its chronological stratification, its spatial creases, its architectural harmony and often even its social dissonance, we are obliged to create a new epistemology which is capable of evaluating and of utilizing the multiplicity of territorial identities and that knows how to activate new forms of project making.

Edge-to-Stem Variability in Wet-Canopy Evaporation From an Urban Tree Row

Science.gov (United States)

Van Stan, John T.; Norman, Zachary; Meghoo, Adrian; Friesen, Jan; Hildebrandt, Anke; Côté, Jean-François; Underwood, S. Jeffrey; Maldonado, Gustavo

2017-11-01

Evaporation from wet-canopy (E_C) and stem (E_S) surfaces during rainfall represents a significant portion of municipal-to-global scale hydrologic cycles. For urban ecosystems, E_C and E_S dynamics play valuable roles in stormwater management. Despite this, canopy-interception loss studies typically ignore crown-scale variability in E_C and assume (with few indirect data) that E_S is generally {<}2% of total wet-canopy evaporation. We test these common assumptions for the first time with a spatially-distributed network of in-canopy meteorological monitoring and 45 surface temperature sensors in an urban Pinus elliottii tree row to estimate E_C and E_S under the assumption that crown surfaces behave as "wet bulbs". From December 2015 through July 2016, 33 saturated crown periods (195 h of 5-min observations) were isolated from storms for determination of 5-min evaporation rates ranging from negligible to 0.67 mm h^{-1}. Mean E_S (0.10 mm h^{-1}) was significantly lower (p < 0.01) than mean E_C (0.16 mm h^{-1}). But, E_S values often equalled E_C and, when scaled to trunk area using terrestrial lidar, accounted for 8-13% (inter-quartile range) of total wet-crown evaporation (E_S+E_C scaled to surface area). E_S contributions to total wet-crown evaporation maximized at 33%, showing a general underestimate (by 2-17 times) of this quantity in the literature. Moreover, results suggest wet-crown evaporation from urban tree rows can be adequately estimated by simply assuming saturated tree surfaces behave as wet bulbs, avoiding problematic assumptions associated with other physically-based methods.

Soil surface temperatures reveal moderation of the urban heat island effect by trees and shrubs

DEFF Research Database (Denmark)

Edmondson, Jill L; Stott, Iain; Davies, Zoe G

2016-01-01

months increased by 0.6 °C over the 5 km from the city outskirts to the centre. Trees and shrubs in non-domestic greenspace reduced mean maximum daily soil surface temperatures in the summer by 5.7 °C compared to herbaceous vegetation, but tended to maintain slightly higher temperatures in winter. Trees...... in domestic gardens, which tend to be smaller, were less effective at reducing summer soil surface temperatures. Our findings reveal that the UHI effects soil temperatures at a city-wide scale, and that in their moderating urban soil surface temperature extremes, trees and shrubs may help to reduce...

The association between urban tree cover and gun assault: A case-control and case-crossover study

Science.gov (United States)

Michelle C. Kondo; Eugenia C. South; Charles C. Branas; Therese S. Richmond; Douglas J. Wiebe

2017-01-01

Green space and vegetation may play a protective role against urban violence. We investigated whether being near urban tree cover during outdoor activities was related to being assaulted with a gun. We conducted geographic information systems–assisted interviews with boys andmen aged 10–24 years in Philadelphia, Pennsylvania, including 135 patients who had been shot...

Tree detection in urban regions from aerial imagery and DSM based on local maxima points

Science.gov (United States)

Korkmaz, Özgür; Yardımcı ćetin, Yasemin; Yilmaz, Erdal

2017-05-01

In this study, we propose an automatic approach for tree detection and classification in registered 3-band aerial images and associated digital surface models (DSM). The tree detection results can be used in 3D city modelling and urban planning. This problem is magnified when trees are in close proximity to each other or other objects such as rooftops in the scenes. This study presents a method for locating individual trees and estimation of crown size based on local maxima from DSM accompanied by color and texture information. For this purpose, segment level classifier trained for 10 classes and classification results are improved by analyzing the class probabilities of neighbour segments. Later, the tree classes under a certain height were eliminated using the Digital Terrain Model (DTM). For the tree classes, local maxima points are obtained and the tree radius estimate is made from the vertical and horizontal height profiles passing through these points. The final tree list containing the centers and radius of the trees is obtained by selecting from the list of tree candidates according to the overlapping and selection parameters. Although the limited number of train sets are used in this study, tree classification and localization results are competitive.

Can Urban Trees Reduce the Impact of Climate Change on Storm Runoff?

Directory of Open Access Journals (Sweden)

Katarina ZABRET

2015-11-01

Full Text Available The process of urbanisation leads to significant changes in surface cover, which influence the hydrological properties of an area. The infiltration of precipitation into the soil is reduced, so that both surface water runoff and the velocity at which water travels have increased drastically. In recent decades climate change has also been observed to affect precipitation trends. Many studies have shown that the amount of rainfall is increasing and that heavy rainfall events are becoming more frequent. These changes are producing more runoff, which has to be drained. Urban trees can reduce the amount of precipitation reaching the ground due to rainfall interception, and are becoming increasingly recognized as an effective means for the regulation of storm water volumes and costs. The study measured rainfall interception in an urban area. It shows that Betula pendula can intercept 20.6% of annual rainfall, whereas Pinus nigra could intercept as much as 51.0% of annual rainfall. The advantage of rainfall interception was shown in the case of a parking lot where the planting of trees was able to reduce runoff by up to 17%.

Urban warming reduces aboveground carbon storage

DEFF Research Database (Denmark)

Meineke, Emily; Youngsteadt, Elsa; Dunn, Robert Roberdeau

2016-01-01

sequestration (carbon stored per year) of mature trees. Urban warming increased herbivorous arthropod abundance on trees, but these herbivores had negligible effects on tree carbon sequestration. Instead, urban warming was associated with an estimated 12% loss of carbon sequestration, in part because...... photosynthesis was reduced at hotter sites. Ecosystem service assessments that do not consider urban conditions may overestimate urban tree carbon storage. Because urban and global warming are becoming more intense, our results suggest that urban trees will sequester even less carbon in the future....

Influence of avenue-trees on air quality at the urban neighborhood scale. Part II: traffic pollutant concentrations at pedestrian level.

Science.gov (United States)

Gromke, Christof; Blocken, Bert

2015-01-01

Flow and dispersion of traffic-emitted pollutants were studied in a generic urban neighborhood for various avenue-tree layouts by employing 3D steady RANS simulations with the realizable k-ε turbulence model. In comparison to the tree-free situation quantitative and qualitative changes with flow reversal in the wind field were observed. Low to moderate increases (pollutant concentration were found at pedestrian level. An approximately 1% increase in the neighborhood-averaged concentration was obtained with each percent of the street canyon volumes being occupied by vegetation for occupation fractions between 4 and 14%. The overall pattern of concentration changes relative to the tree-free situation was similar for all avenue-tree layouts. However, pronounced locally restricted decreases or increases in concentration (-87 to +1378%) occurred. The results indicate the necessity to account for existing or planned avenue-trees in neighborhood scaled is dispersion studies. Their consideration is prerequisite for reliable urban air quality assessment.

An alternative method for estimating crown characteristics of urban trees using digital photographs

Science.gov (United States)

Matthew F. Winn; Philip A. Araman

2012-01-01

The USDA Forest Service Forest Inventory and Analysis (FIA) program has concluded that statewide urban forest inventories are feasible based on a series of pilot studies initiated in 2001. However, much of the tree crown data collected during inventories are based on visual inspection and therefore highly subjective. In order to objectively determine the crown...

Effects of light pollution on tree phenology in the urban environment

Directory of Open Access Journals (Sweden)

Škvareninová Jana

2017-12-01

Full Text Available Research on urban climates has been an important topic in recent years, given the growing number of city inhabitants and significant influences of climate on health. Nevertheless, far less research has focused on the impacts of light pollution, not only on humans, but also on plants and animals in the landscape. This paper reports a study measuring the intensity of light pollution and its impact on the autumn phenological phases of tree species in the town of Zvolen (Slovakia. The research was carried out at two housing estates and in the central part of the town in the period 2013–2016. The intensity of ambient nocturnal light at 18 measurement points was greater under cloudy weather than in clear weather conditions. Comparison with the ecological standard for Slovakia showed that average night light values in the town centre and in the housing estate with an older type of public lighting, exceeded the threshold value by 5 lux. Two tree species, sycamore maple (Acer pseudoplatanus L. and staghorn sumac (Rhus typhina L., demonstrated sensitivity to light pollution. The average onset of the autumn phenophases in the crown parts situated next to the light sources was delayed by 13 to 22 days, and their duration was prolonged by 6 to 9 days. There are three major results: (i the effects of light pollution on organisms in the urban environment are documented; (ii the results provide support for a theoretical and practical basis for better urban planning policies to mitigate light pollution effects on organisms; and (iii some limits of the use of plant phenology as a bioindicator of climate change are presented.

Effects of trees on momentum exchange within and above a real urban environment

Science.gov (United States)

Salesky, S.; Giometto, M. G.; Christen, A.; Egli, P. E.; Schmid, M. F.; Tooke, T. R.; Coops, N. C.; Parlange, M. B.

2017-12-01

Large-eddy simulations (LES) are used to gain insight into the effects of trees on momentum transfer rates characterizing the atmosphere within and above a real urban canopy. Several areas are considered that are part of a neighbourhood in the city of Vancouver, BC, Canada where a small fraction of trees are taller than buildings. In this area, eight years of continuous wind and turbulence measurements are available from a 30 m meteorological tower. Buildings and vegetation geometries are obtained from airborne light detection and ranging (LiDAR) data. In the LES algorithm, buildings are accounted through an immersed boundary method, whereas vegetation is parameterized via a location-specific leaf area density. LES are performed varying wind direction and leaf area densities. Surface roughness lengths (z0) from both LES and tower measurements are sensitive to the 0 ≤ LAI/λ lower than the 27% increase featured by LES for the most representative canopy (leaves-off LAI/λ = 0.74, leaves-on LAI/λ = 2.24). Removing vegetation from such a canopy would cause a dramatic drop of approximately 50% in z0 when compared to the reference summer value. The momentum displacement height (d) from LES also consistently increases as LAI/λ increases, due to the disproportionate amount of drag that the (few) relatively taller trees exert on the flow. Within the urban canopy, the effects of trees are twofold: on one hand, they act as a direct momentum sink for the mean flow; on the other, they reduce downward turbulent transport of high-momentum fluid, significantly reducing the wind intensity at the heights where people live and buildings consume energy.

Non-native tree species in urban areas of the city of Nitra

International Nuclear Information System (INIS)

Galis, M

2014-01-01

Non-native plant species are part of our environment. The introduction of these species is huge conditioned by anthropogenic activities, such as the urban environment is characterized by. During the field surveys of selected town Nitra (Chrenova, Mikova Ves, Zobor), we studied the frequency of non-native tree species in the contact zone. Overall, we found out the presence of 10 alien species, observed in this area. Our results show dominant presence of the species Rhus typhina, followed by the Robinia pseudoacacia and Ailanthus altissima. Individual plants were tied largely to the surrounding of built-up areas, often growns directly in front of houses, or as a part of urban green. (author)

Reducing construction waste: A study of urban infrastructure projects.

Science.gov (United States)

de Magalhães, Ruane Fernandes; Danilevicz, Ângela de Moura Ferreira; Saurin, Tarcisio Abreu

2017-09-01

The construction industry is well-known for producing waste detrimental to the environment, and its impacts have increased with the development process of cities. Although there are several studies focused on the environmental impact of residential and commercial buildings, less knowledge is available regarding decreasing construction waste (CW) generation in urban infrastructure projects. This study presents best practices to reduce waste in the said projects, stressing the role of decision-making in the design stage and the effective management of construction processes in public sector. The best practices were identified from literature review, document analysis in 14 projects of urban infrastructure, and both qualitative and quantitative survey with 18 experts (architects and engineers) playing different roles on those projects. The contributions of these research are: (i) the identification of the main building techniques related to the urban design typologies analyzed; (ii) the identification of cause-effect relationships between the design choices and the CW generation diagnosis; (iii) the proposal of a checklist to support the decision-making process, that can be used as a control and evaluation instrument when developing urban infrastructure designs, focused on the construction waste minimization (CWM). Copyright © 2017 Elsevier Ltd. All rights reserved.

Dispersion of traffic exhausts in urban street canyons with tree plantings : experimental and numerical investigations

NARCIS (Netherlands)

Gromke, C.B.; Denev, J.; Ruck, B.

2007-01-01

Wind tunnel experiments and numerical computations have been performed in order to investigate the influence of avenuelike tree plantings on the dispersion of traffic exhaust in an urban street canyon. Reduced natural ventilation and enhanced pollutant concentrations have been found in the presence

Comparing estimates of EMEP MSC-Wand UFORE models in air pollutant reduction by urban trees

Czech Academy of Sciences Publication Activity Database

Guidolotti, G.; Salvatio, M.; Calfapietra, Carlo

2016-01-01

Roč. 23, č. 19 (2016), s. 19541-19550 ISSN 0944-1344 Institutional support: RVO:67179843 Keywords : i-Tree * UFORE, EMEP/MSC-Wmodel * urban forest * atmospheric pollutants * O3 * NO2 * PM10 Subject RIV: EF - Botanics Impact factor: 2.741, year: 2016

Persistence of long-distance, insect-mediated pollen movement for a tropical canopy tree species in remnant forest patches in an urban landscape.

Science.gov (United States)

Noreen, A M E; Niissalo, M A; Lum, S K Y; Webb, E L

2016-12-01

As deforestation and urbanization continue at rapid rates in tropical regions, urban forest patches are essential repositories of biodiversity. However, almost nothing is known about gene flow of forest-dependent tree species in urban landscapes. In this study, we investigated gene flow in the insect-pollinated, wind-dispersed tropical tree Koompassia malaccensis in and among three remnant forest patches in the urbanized landscape of Singapore. We genotyped the vast majority of adults (N=179) and a large number of recruits (N=2103) with 8 highly polymorphic microsatellite markers. Spatial genetic structure of the recruit and adult cohorts was significant, showing routine gene dispersal distances of ~100-400 m. Parentage analysis showed that 97% of recruits were within 100 m of their mother tree, and a high frequency of relatively short-distance pollen dispersal (median ~143-187 m). Despite routine seed and pollen dispersal distances of within a few hundred meters, interpatch gene flow occurred between all patches and was dominated by pollen movement: parentage analysis showed 76 pollen versus 2 seed interpatch dispersal events, and the seedling neighborhood model estimated ~1-6% seed immigration and ~21-46% pollen immigration rates, depending on patch. In addition, the smallest patch (containing five adult K. malaccensis trees) was entirely surrounded by >2.5 km of 'impervious' substrate, yet had the highest proportional pollen and seed immigration estimates of any patch. Hence, contrary to our hypothesis, insect-mediated gene flow persisted across an urban landscape, and several of our results also parallel key findings from insect-pollinated canopy trees sampled in mixed agricultural-forest landscapes.

Using urban forest assessment tools to model bird habitat potential

Science.gov (United States)

Lerman, Susannah B.; Nislow, Keith H.; Nowak, David J.; DeStefano, Stephen; King, David I.; Jones-Farrand, D. Todd

2014-01-01

The alteration of forest cover and the replacement of native vegetation with buildings, roads, exotic vegetation, and other urban features pose one of the greatest threats to global biodiversity. As more land becomes slated for urban development, identifying effective urban forest wildlife management tools becomes paramount to ensure the urban forest provides habitat to sustain bird and other wildlife populations. The primary goal of this study was to integrate wildlife suitability indices to an existing national urban forest assessment tool, i-Tree. We quantified available habitat characteristics of urban forests for ten northeastern U.S. cities, and summarized bird habitat relationships from the literature in terms of variables that were represented in the i-Tree datasets. With these data, we generated habitat suitability equations for nine bird species representing a range of life history traits and conservation status that predicts the habitat suitability based on i-Tree data. We applied these equations to the urban forest datasets to calculate the overall habitat suitability for each city and the habitat suitability for different types of land-use (e.g., residential, commercial, parkland) for each bird species. The proposed habitat models will help guide wildlife managers, urban planners, and landscape designers who require specific information such as desirable habitat conditions within an urban management project to help improve the suitability of urban forests for birds.

Modeling the effect of urban infrastructure on hydrologic processes within i-Tree Hydro, a statistically and spatially distributed model

Science.gov (United States)

Taggart, T. P.; Endreny, T. A.; Nowak, D.

2014-12-01

Gray and green infrastructure in urban environments alters many natural hydrologic processes, creating an urban water balance unique to the developed environment. A common way to assess the consequences of impervious cover and grey infrastructure is by measuring runoff hydrographs. This focus on the watershed outlet masks the spatial variation of hydrologic process alterations across the urban environment in response to localized landscape characteristics. We attempt to represent this spatial variation in the urban environment using the statistically and spatially distributed i-Tree Hydro model, a scoping level urban forest effects water balance model. i-Tree Hydro has undergone expansion and modification to include the effect of green infrastructure processes, road network attributes, and urban pipe system leakages. These additions to the model are intended to increase the understanding of the altered urban hydrologic cycle by examining the effects of the location of these structures on the water balance. Specifically, the effect of these additional structures and functions on the spatially varying properties of interception, soil moisture and runoff generation. Differences in predicted properties and optimized parameter sets between the two models are examined and related to the recent landscape modifications. Datasets used in this study consist of watersheds and sewersheds within the Syracuse, NY metropolitan area, an urban area that has integrated green and gray infrastructure practices to alleviate stormwater problems.

CFD modelling of the aerodynamic effect of trees on urban air pollution dispersion.

Science.gov (United States)

Amorim, J H; Rodrigues, V; Tavares, R; Valente, J; Borrego, C

2013-09-01

The current work evaluates the impact of urban trees over the dispersion of carbon monoxide (CO) emitted by road traffic, due to the induced modification of the wind flow characteristics. With this purpose, the standard flow equations with a kε closure for turbulence were extended with the capability to account for the aerodynamic effect of trees over the wind field. Two CFD models were used for testing this numerical approach. Air quality simulations were conducted for two periods of 31h in selected areas of Lisbon and Aveiro, in Portugal, for distinct relative wind directions: approximately 45° and nearly parallel to the main avenue, respectively. The statistical evaluation of modelling performance and uncertainty revealed a significant improvement of results with trees, as shown by the reduction of the NMSE from 0.14 to 0.10 in Lisbon, and from 0.14 to 0.04 in Aveiro, which is independent from the CFD model applied. The consideration of the plant canopy allowed to fulfil the data quality objectives for ambient air quality modelling established by the Directive 2008/50/EC, with an important decrease of the maximum deviation between site measurements and CFD results. In the non-aligned wind situation an average 12% increase of the CO concentrations in the domain was observed as a response to the aerodynamic action of trees over the vertical exchange rates of polluted air with the above roof-level atmosphere; while for the aligned configuration an average 16% decrease was registered due to the enhanced ventilation of the street canyon. These results show that urban air quality can be optimised based on knowledge-based planning of green spaces. Copyright © 2013 Elsevier B.V. All rights reserved.

Spatial distribution assessment of particulate matter in an urban street canyon using biomagnetic leaf monitoring of tree crown deposited particles

International Nuclear Information System (INIS)

Hofman, Jelle; Stokkaer, Ines; Snauwaert, Lies; Samson, Roeland

2013-01-01

Recently, biomagnetic monitoring of tree leaves has proven to be a good estimator for ambient particulate concentration. This paper investigates the usefulness of biomagnetic leaf monitoring of crown deposited particles to assess the spatial PM distribution inside individual tree crowns and an urban street canyon in Ghent (Belgium). Results demonstrate that biomagnetic monitoring can be used to assess spatial PM variations, even within single tree crowns. SIRM values decrease exponentially with height and azimuthal effects are obtained for wind exposed sides of the street canyon. Edge and canyon trees seem to be exposed differently. As far as we know, this study is the first to present biomagnetic monitoring results of different trees within a single street canyon. The results not only give valuable insights into the spatial distribution of particulate matter inside tree crowns and a street canyon, but also offer a great potential as validation tool for air quality modelling. Highlights: ► Spatial distribution of tree crown deposited PM was evaluated. ► SIRM values decrease exponentially with height. ► Azimuthal effects were observed at wind exposed sides of the street canyon. ► Edge and canyon trees seem to be exposed differently. ► Biomagnetic monitoring offers a great potential as validation of air quality models. -- Biomagnetic leaf monitoring provides useful insights into the spatial distribution of particulates inside individual tree crowns and an urban street canyon in Ghent (Belgium)

Woody Vegetation Composition and Structure in Peri-urban Chongming Island, China

Science.gov (United States)

Zhao, Min; Escobedo, Francisco J.; Wang, Ruijing; Zhou, Qiaolan; Lin, Wenpeng; Gao, Jun

2013-05-01

Chongming, the world's largest alluvial island, is located within the municipality of Shanghai, China. Recent projects have now linked peri-urban Chongming to Shanghai's urban core and as a result will soon undergo substantial changes from urbanization. We quantitatively analyzed the structure and composition of woody vegetation across subtropical, peri-urban Chongming as a basis for sustainable management of these rapidly urbanizing subtropical ecosystems elsewhere. We used 178 permanent, random plots to statistically and spatially analyze woody plant composition and tree structure across the 1,041 km2 of Chongming. A total of 2,251 woody plants were measured comprising 42 species in 37 genera. We statistically and geospatially analyzed field data according to land uses and modeled air pollution removal by trees. Average tree diameter at breast height, total height, and crown widths on transportation land uses were greater than other land uses. These same values were lowest on forest land use and greater tree cover was associated with areas of increased anthropogenic activity. Less than 20 % of the woody vegetation was exotic and a species richness index was significantly different between land uses due to legacy effects. Composition of agriculture and forest land uses were similar to residential and transportation. Tree cover across Chongming was also estimated to annually remove 1,400 tons of air pollutants. We propose that this integrated and quantitative method can be used in other subtropical, peri-urban areas in developing countries to establish baseline trends for future sustainability objectives and to monitor the effects of urbanization and climate change.

Mobbing call experiment suggests the enhancement of forest bird movement by tree cover in urban landscapes across seasons

Directory of Open Access Journals (Sweden)

Atsushi Shimazaki

2017-06-01

Full Text Available Local scale movement behavior is an important basis to predict large-scale bird movements in heterogeneous landscapes. Here we conducted playback experiments using mobbing calls to estimate the probability that forest birds would cross a 50-m urban area during three seasons (breeding, dispersal, and wintering seasons with varying amounts of tree cover, building area, and electric wire density. We examined the responses of four forest resident species: Marsh Tit (Poecile palustris, Varied Tit (Sittiparus varius, Japanese Tit (P. minor, and Eurasian Nuthatch (Sitta europaea in central Hokkaido, northern Japan. We carried out and analyzed 250 playback experiments that attracted 618 individuals. Our results showed that tree cover increased the crossing probability of three species other than Varied Tit. Building area and electric wire density had no detectable effect on crossing probability for four species. Seasonal difference in the crossing probability was found only for Varied Tit, and the probability was the highest in the breeding season. These results suggest that the positive effect of tree cover on the crossing probability would be consistent across seasons. We therefore conclude that planting trees would be an effective way to promote forest bird movement within an urban landscape.

Citizens' distrust of government and their protest responses in a contingent valuation study of urban heritage trees in Guangzhou, China.

Science.gov (United States)

Chen, Wendy Y; Hua, Junyi

2015-05-15

Protest response is a common aspect of contingent valuation (CV) studies, which has attracted growing attention from scholars worldwide. Distrust of government, understood as one of the major reasons for protest response, has been prevalent across transitional China experiencing dramatic changes in its economy, society and natural environment. Citizen distrust of government would significantly hinder the efficiency and validity of the contingent valuation method (CVM) application focusing on the provision of public environmental and ecological goods in China, as a large proportion of protest responses might be induced. Hitherto little has been done to link residents' trust in government to their environmental behaviors in developing and transitional economies like China where CVM has been increasingly applied to generate meaningful and reliable information for integrating both ecological and socioeconomic perspectives into policy decisions. This study aims to investigate the discrepancies between protest responses induced by distrust of government and non-protest responses, using the contingent valuation of heritage trees in Guangzhou as a case. The combination of a set of debriefing questions and several attitudinal questions is employed in the questionnaire. Based on logit analysis and discriminant analysis, it has been found that protestors who distrust government and non-protestors share similar salient values associated with urban heritage trees in Guangzhou, especially their distinctive historical and cultural values, in comparison with ordinary urban trees. Residents with low familiarity with heritage trees (who rarely visit sites with heritage trees, know little about management and conservation techniques, and consider present management to be ineffective) are likely to act as protesters with the "distrust of government" belief. Only if more opportunities are provided for residents to obtain access to urban heritage tree sites, more information (about

Assessing the Effects of the Urban Forest Restoration Effort of MillionTreesNYC on the Structure and Functioning of New York City Ecosystems

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P. Timon McPhearson

2010-01-01

Full Text Available Current forest restoration practices for New York City’s (NYC MillionTreesNYC Initiative on public parkland include site preparation with extensive invasive species removal and tree and shrub planting with the goal of creating new multi-layered forests. We have launched a long-term investigation of these sites in order to understand the primary physical, chemical, and biological responses of urban ecosystems to MillionTreesNYC forest restoration practices. This research will examine high and low diversity tree and understory planting combinations in permanent experimental forest restoration plots across NYC. The study assesses how the interactions between soil heterogeneity, plant population dynamics, and forest restoration management strategies drive urban forest ecosystem structure and functioning. Working in collaboration with the NYC Department of Parks & Recreation (NYC Parks and the MillionTreesNYC tree planting campaign, we are examining different restoration strategies to assess how restoration practices affect the ecological development trajectories of newly established forests in NYC.

Long-term monitoring of Sacramento Shade program trees: tree survival, growth and energy-saving performance

Science.gov (United States)

Yekang Ko; Jun-Hak Lee; E. Gregory McPherson; Lara A. Roman

2015-01-01

Long-term survival and growth of urban forests are critical to achieve the targeted benefits of urban tree planting programs, such as building energy savings from tree shade. However, little is known about how trees perform in the long-term, especially in residential areas. Given this gap in the literature, we monitored 22-years of post-planting survival, growth, and...

Projecting land-use and land cover change in a subtropical urban watershed

Science.gov (United States)

John J. Lagrosa IV; Wayne C. Zipperer; Michael G. Andreu

2018-01-01

Urban landscapes are heterogeneous mosaics that develop via significant land-use and land cover (LULC) change. Current LULC models project future landscape patterns, but generally avoid urban landscapes due to heterogeneity. To project LULC change for an urban landscape, we parameterize an established LULC model (Dyna-CLUE) under baseline conditions (continued current...

Assessing urban forest effects and values, Scranton's urban forest

Science.gov (United States)

David J. Nowak; Robert E. III Hoehn; Daniel E. Crane; Jack C. Stevens; Vincent. Cotrone

2010-01-01

An analysis of trees in the urbanized portion of Scranton, PA, reveals that this area has about 1.2 million trees with canopies that cover 22.0 percent of the area. The most common tree species are red maple, gray birch, black cherry, northern red oak, and quaking aspen. Scranton's urban forest currently store about 93,300 tons of carbon valued at $1.9 million. In...

Office of Legacy Management Decision Tree for Solar Photovoltaic Projects - 13317

Energy Technology Data Exchange (ETDEWEB)

Elmer, John; Butherus, Michael [S.M. Stoller Corporation (United States); Barr, Deborah L. [U.S. Department of Energy Office of Legacy Management (United States)

2013-07-01

To support consideration of renewable energy power development as a land reuse option, the DOE Office of Legacy Management (LM) and the National Renewable Energy Laboratory (NREL) established a partnership to conduct an assessment of wind and solar renewable energy resources on LM lands. From a solar capacity perspective, the larger sites in the western United States present opportunities for constructing solar photovoltaic (PV) projects. A detailed analysis and preliminary plan was developed for three large sites in New Mexico, assessing the costs, the conceptual layout of a PV system, and the electric utility interconnection process. As a result of the study, a 1,214-hectare (3,000-acre) site near Grants, New Mexico, was chosen for further study. The state incentives, utility connection process, and transmission line capacity were key factors in assessing the feasibility of the project. LM's Durango, Colorado, Disposal Site was also chosen for consideration because the uranium mill tailings disposal cell is on a hillside facing south, transmission lines cross the property, and the community was very supportive of the project. LM worked with the regulators to demonstrate that the disposal cell's long-term performance would not be impacted by the installation of a PV solar system. A number of LM-unique issues were resolved in making the site available for a private party to lease a portion of the site for a solar PV project. A lease was awarded in September 2012. Using a solar decision tree that was developed and launched by the EPA and NREL, LM has modified and expanded the decision tree structure to address the unique aspects and challenges faced by LM on its multiple sites. The LM solar decision tree covers factors such as land ownership, usable acreage, financial viability of the project, stakeholder involvement, and transmission line capacity. As additional sites are transferred to LM in the future, the decision tree will assist in determining

Office of Legacy Management Decision Tree for Solar Photovoltaic Projects - 13317

International Nuclear Information System (INIS)

Elmer, John; Butherus, Michael; Barr, Deborah L.

2013-01-01

To support consideration of renewable energy power development as a land reuse option, the DOE Office of Legacy Management (LM) and the National Renewable Energy Laboratory (NREL) established a partnership to conduct an assessment of wind and solar renewable energy resources on LM lands. From a solar capacity perspective, the larger sites in the western United States present opportunities for constructing solar photovoltaic (PV) projects. A detailed analysis and preliminary plan was developed for three large sites in New Mexico, assessing the costs, the conceptual layout of a PV system, and the electric utility interconnection process. As a result of the study, a 1,214-hectare (3,000-acre) site near Grants, New Mexico, was chosen for further study. The state incentives, utility connection process, and transmission line capacity were key factors in assessing the feasibility of the project. LM's Durango, Colorado, Disposal Site was also chosen for consideration because the uranium mill tailings disposal cell is on a hillside facing south, transmission lines cross the property, and the community was very supportive of the project. LM worked with the regulators to demonstrate that the disposal cell's long-term performance would not be impacted by the installation of a PV solar system. A number of LM-unique issues were resolved in making the site available for a private party to lease a portion of the site for a solar PV project. A lease was awarded in September 2012. Using a solar decision tree that was developed and launched by the EPA and NREL, LM has modified and expanded the decision tree structure to address the unique aspects and challenges faced by LM on its multiple sites. The LM solar decision tree covers factors such as land ownership, usable acreage, financial viability of the project, stakeholder involvement, and transmission line capacity. As additional sites are transferred to LM in the future, the decision tree will assist in determining whether a solar

Is All Urban Green Space the Same? A Comparison of the Health Benefits of Trees and Grass in New York City.

Science.gov (United States)

Reid, Colleen E; Clougherty, Jane E; Shmool, Jessie L C; Kubzansky, Laura D

2017-11-18

Living near vegetation, often called "green space" or "greenness", has been associated with numerous health benefits. We hypothesized that the two key components of urban vegetation, trees and grass, may differentially affect health. We estimated the association between near-residence trees, grass, and total vegetation (from the 2010 High Resolution Land Cover dataset for New York City (NYC)) with self-reported health from a survey of NYC adults (n = 1281). We found higher reporting of "very good" or "excellent" health for respondents with the highest, compared to the lowest, quartiles of tree (RR = 1.23, 95% CI = 1.06-1.44) but not grass density (relative risk (RR) = 1.00, 95% CI = 0.86-1.17) within 1000 m buffers, adjusting for pertinent confounders. Significant positive associations between trees and self-reported health remained after adjustment for grass, whereas associations with grass remained non-significant. Adjustment for air pollutants increased beneficial associations between trees and self-reported health; adjustment for parks only partially attenuated these effects. Results were null or negative using a 300 m buffer. Findings imply that higher exposure to vegetation, particularly trees outside of parks, may be associated with better health. If replicated, this may suggest that urban street tree planting may improve population health.

APPLIED BOTANY, I. PROTECTION OF TREES AND BUSHES IN THE INVESTMENT PROCESS IN URBAN AREAS

Directory of Open Access Journals (Sweden)

Mariola Garczyńska

2017-06-01

Full Text Available Ecosystem services are the benefits resulting from resources and processes in nature. Trees and stand densities constitute a significant element of the landscape (both in urban and rural areas and serve a number of ecosystem functions, forming an inherent part of each group of benefits singled out on the basis of the Millennium Ecosystem Assessment. In the thesis, selected ecosystem services of trees and stand densities were detailed - provisioning, regulatory, supporting and cultural functions. Diagnosis of services performed by trees and their valuation may contribute to taking increased care of them and protection during performing various investments, it is therefore appropriate to launch multifaceted ecological education to each person, particularly to those directly responsible for trees and bushes in towns and rural areas. In order to restrict construction stress to trees and bushes, environmental impact assessment has to be made as soon as the construction planning is being made (natural, cultural and landscape conditions should be provided additionally, it is advisable to conduct a dendrological inventory for planning purposes. Appropriate protection of trees and standing densities is also legally regulated by the Nature Conservation Act and the Construction Law. During the investment process, the trees and their settlement conditions should be adequately secured , so that it will not affect their viability. After completed investment, the condition of the tree stand should be monitored.

Large urban projects and social actors : Forces supporting and opposing the production

NARCIS (Netherlands)

Cuenya, B.E.

2006-01-01

This research studies, by means of the analysis of a paradigmatic large urban project in Buenos Aires, the production process of a large urban project furthered by the State and directed to create a new centrality. The analysis is focused on the forces supporting and opposition the project that were

How to select the best tree planting locations to enhance air pollution removal in the MillionTreesNYC initiative

International Nuclear Information System (INIS)

Morani, Arianna; Nowak, David J.; Hirabayashi, Satoshi; Calfapietra, Carlo

2011-01-01

Highest priority zones for tree planting within New York City were selected by using a planting priority index developed combining three main indicators: pollution concentration, population density and low canopy cover. This new tree population was projected through time to estimate potential air quality and carbon benefits. Those trees will likely remove more than 10 000 tons of air pollutants and a maximum of 1500 tons of carbon over the next 100 years given a 4% annual mortality rate. Cumulative carbon storage will be reduced through time as carbon loss through tree mortality outweighs carbon accumulation through tree growth. Model projections are strongly affected by mortality rate whose uncertainties limit estimations accuracy. Increasing mortality rate from 4 to 8% per year produce a significant decrease in the total pollution removal over a 100 year period from 11 000 tons to 3000 tons. - Highlights: → The manuscript is part of the IUFRO Special section 'Adaptation of Forest Ecosystems to Air Pollution and Climate Change' (Elena Paoletti and Yusuf Serengil Eds.) approved by William J. Manning. → It has been already peer-reviewed and accepted outside EES. → The reference number of this manuscript is IUFRO49. - Carbon and air pollutant uptake by urban forests are highly influenced by mortality rates.

How to select the best tree planting locations to enhance air pollution removal in the MillionTreesNYC initiative

Energy Technology Data Exchange (ETDEWEB)

Morani, Arianna [Institute of Agro-Environmental and Forest Biology (IBAF), National Research Council (CNR) Via Salaria km 29300, 00015 Monterotondo Scalo, Roma (Italy); Nowak, David J.; Hirabayashi, Satoshi [USDA Forest Service, Northern Research Station, 5 Moon Library, SUNY-ESF, Syracuse, NY 13210 (United States); Calfapietra, Carlo, E-mail: carlo.calfapietra@ibaf.cnr.it [Institute of Agro-Environmental and Forest Biology (IBAF), National Research Council (CNR) Via Salaria km 29300, 00015 Monterotondo Scalo, Roma (Italy)

2011-05-15

Highest priority zones for tree planting within New York City were selected by using a planting priority index developed combining three main indicators: pollution concentration, population density and low canopy cover. This new tree population was projected through time to estimate potential air quality and carbon benefits. Those trees will likely remove more than 10 000 tons of air pollutants and a maximum of 1500 tons of carbon over the next 100 years given a 4% annual mortality rate. Cumulative carbon storage will be reduced through time as carbon loss through tree mortality outweighs carbon accumulation through tree growth. Model projections are strongly affected by mortality rate whose uncertainties limit estimations accuracy. Increasing mortality rate from 4 to 8% per year produce a significant decrease in the total pollution removal over a 100 year period from 11 000 tons to 3000 tons. - Highlights: > The manuscript is part of the IUFRO Special section 'Adaptation of Forest Ecosystems to Air Pollution and Climate Change' (Elena Paoletti and Yusuf Serengil Eds.) approved by William J. Manning. > It has been already peer-reviewed and accepted outside EES. > The reference number of this manuscript is IUFRO49. - Carbon and air pollutant uptake by urban forests are highly influenced by mortality rates.

Introducing Urban Food Forestry: A Multifunctional Strategy for Enhancing Urban Sustainability

Science.gov (United States)

Nicholas, K. A.; Clark, K.

2012-12-01

We propose combining elements of urban agriculture and urban forestry into what we call "urban food forestry" (UFF), the practice of growing perennial woody food-producing species ("food trees") in cities. We used four approaches at different scales to gauge the potential of UFF to enhance urban sustainability, in the context of trends including increasing urbanization, resource demands, and climate change. First, we analyzed 37 current international initiatives based around urban food trees, finding that core activities included planting, mapping, and harvesting food trees, but that only about a quarter of initiatives engaged in more than one of these activities necessary to fully utilize the food potential of urban trees. Second, we analyzed 30 urban forestry master plans, finding that only 13% included human food security among their objectives. Third, we used Burlington, Vermont as a case study to quantify the potential caloric output of publicly accessible open space if planted with Malus domestica (the common apple) under 9 different scenarios. We found that the entire caloric deficit of the very low food security population could be met on as few as 29 hectares (representing 16% of total open space), and that 98% of the daily recommended minimum intake of fruit for the entire city's population could be met under the most ambitious planting scenario. Finally, we developed a decision-making tool for selecting potential food trees appropriate for temperate urban environments, the Climate-Food-Species Matrix. We identified a total of 70 species, 30 of which we deemed "highly suitable" for urban food forestry based on their cold hardiness, drought tolerance, and edibility. We conclude that urban food forestry provides multiple pathways for building urban sustainability through local food production, and that our framework can be used to increase the coordination between and effectiveness of a growing number of related initiatives.

Tree hole mosquito species composition and relative abundances differ between urban and adjacent forest habitats in northwestern Argentina.

Science.gov (United States)

Mangudo, C; Aparicio, J P; Rossi, G C; Gleiser, R M

2018-04-01

Water-holding tree holes are main larval habitats for many pathogen vectors, especially mosquitoes (Diptera: Culicidae). Along 3 years, the diversity and composition of mosquito species in tree holes of two neighbouring but completely different environments, a city and its adjacent forest, were compared using generalized linear mixed models, PERMANOVA, SIMPER and species association indexes. The city area (Northwest Argentina) is highly relevant epidemiologically due to the presence of Aedes aegypti L. (main dengue vector) and occurrence of dengue outbreaks; the Yungas rainforests are highly biologically diverse. In total seven mosquito species were recorded, in descending order of abundance: Ae. aegypti, Haemagogus spegazzinii Brèthes, Sabethes purpureus (Theobald), Toxorhynchites guadeloupensis Dyar and Knab, Aedes terrens Walker, Haemagogus leucocelaenus Dyar & Shannon and Sabethes petrocchiae (Shannon and Del Ponte). The seven mosquito species were recorded in both city sites and forested areas; however, their mosquito communities significantly diverged because of marked differences in the frequency and relative abundance of some species: Tx. guadeloupensis and Ae. aegypti were significantly more abundant in forest and urban areas, respectively. Positive significant associations were detected between Ae. aegypti, Hg. spegazzinii and Hg. leucocelaenus. The combined presence of Ae. aegypti, Haemagogus and Sabethes in the area also highlight a potential risk of yellow fever epidemics. Overall results show an impoverished tree hole mosquito fauna in urban environments, reflecting negative effects of urbanization on mosquito diversity.

Development of a CFD Model Including Tree's Drag Parameterizations: Application to Pedestrian's Wind Comfort in an Urban Area

Science.gov (United States)

Kang, G.; Kim, J.

2017-12-01

This study investigated the tree's effect on wind comfort at pedestrian height in an urban area using a computational fluid dynamics (CFD) model. We implemented the tree's drag parameterization scheme to the CFD model and validated the simulated results against the wind-tunnel measurement data as well as LES data via several statistical methods. The CFD model underestimated (overestimated) the concentrations on the leeward (windward) walls inside the street canyon in the presence of trees, because the CFD model can't resolve the latticed cage and can't reflect the concentration increase and decrease caused by the latticed cage in the simulations. However, the scalar pollutants' dispersion simulated by the CFD model was quite similar to that in the wind-tunnel measurement in pattern and magnitude, on the whole. The CFD model overall satisfied the statistical validation indices (root normalized mean square error, geometric mean variance, correlation coefficient, and FAC2) but failed to satisfy the fractional bias and geometric mean bias due to the underestimation on the leeward wall and overestimation on the windward wall, showing that its performance was comparable to the LES's performance. We applied the CFD model to evaluation of the trees' effect on the pedestrian's wind-comfort in an urban area. To investigate sensory levels for human activities, the wind-comfort criteria based on Beaufort wind-force scales (BWSs) were used. In the tree-free scenario, BWS 4 and 5 (unpleasant condition for sitting long and sitting short, respectively) appeared in the narrow spaces between buildings, in the upwind side of buildings, and the unobstructed areas. In the tree scenario, BWSs decreased by 1 3 grade inside the campus of Pukyong National University located in the target area, which indicated that trees planted in the campus effectively improved pedestrian's wind comfort.

Assessing the ecosystem service potential of Tucson AZ's urban forest

Science.gov (United States)

Pavao-Zuckerman, M.

2011-12-01

canopy photos) to asses growth of the trees in the urban environment. These growth rates, and associated ecosystem services (C-sequestration, energy savings, pollution mitigation, etc.) are evaluated using US Forest Service models (Tree Carbon Calculator and i-tree software) to determine how the performance of trees in the Tucson urban environment perform vs. model predictions. We hypothesize that the models overestimate tree performance as Tucson differs in water availability relative to the cities the model was parameterized in (e.g. Glendale), both in terms of soil water holding capacities and also city "water culture." This preliminary study will provide a data collection framework for a citizen science urban forestry project which will provide data to improve environmental decision making related to the interaction of plants, water, and energy balance in this arid city.

Multiple benefits and values of trees in urban landscapes in two small towns in northern South Africa

NARCIS (Netherlands)

Shackleton, S.; Chinyimba, A.; Hebinck, P.G.M.; Shackleton, C.; Kaoma, H.

2015-01-01

Cities and towns can be conceptualised as complex social-ecological systems or landscapes that are composed of different spatial elements. Trees in urban landscapes provide a variety of tangible and intangible benefits (ecosystem services) that may be valued differently across diverse households and

Dispersal limitation at the expanding range margin of an evergreen tree in urban habitats?

DEFF Research Database (Denmark)

Møller, Linda Agerbo; Skou, Anne-Marie Thonning; Kollmann, Johannes Christian

2012-01-01

Dispersal limitations contribute to shaping plant distribution patterns and thus are significant for biodiversity conservation and urban ecology. In fleshy-fruited plants, for example, any preference of frugivorous birds affects dispersal capacities of certain fruit species. We conducted a removal...... landscapes. The results should be included in urban forestry and planting of potentially invasive ornamental species. © 2011 Elsevier GmbH. All rights reserved....... experiment with fruits of Ilex aquifolium, a species that is currently expanding its range margin in northern Europe in response to climate change. The species is also a popular ornamental tree and naturalization has been observed in many parts of its range. Fruits of native I. aquifolium and of three...

A method to study the management of urban development projects

NARCIS (Netherlands)

Heurkens, E.

2011-01-01

The management of urban development projects in the Netherlands has changed significantly in recent years. These projects have become mainly ‘led’ by developers as they manage the entire life cycle of development projects, while public actors mainly facilitate development projects. This changes the

The distribution on trees of dry deposited material from the Chernobyl accident

International Nuclear Information System (INIS)

Roed, J.

1988-01-01

The distribution of material from the Chernobyl accident that has been dry deposited on forest trees near Roskilde (Denmark) and on trees in a suburban area of Roskilde are investigated. The dry deposition velocities on the plan-projected area covered by the trees are found and compared with those on paved surfaces. The conclusion is that the deposited material is distributed fairly uniformly on the trees, and that the deposition velocities on trees are more than 10 times higher than on paved surfaces. A bulk deposition constant is defined and proposed to be used for modelling the deposition on trees in an urban environment. This work was supported by the EEC Radiation Protection Programme under contract No. B16-107-DK and by NKA, the Nordic Liaison Committee for Atomic Energy

Atmospheric pollution in an urban environment by tree bark biomonitoring--part I: trace element analysis.

Science.gov (United States)

Guéguen, Florence; Stille, Peter; Lahd Geagea, Majdi; Boutin, René

2012-03-01

Tree bark has been shown to be a useful biomonitor of past air quality because it accumulates atmospheric particulate matter (PM) in its outermost structure. Trace element concentrations of tree bark of more than 73 trees allow to elucidate the impact of past atmospheric pollution on the urban environment of the cities of Strasbourg and Kehl in the Rhine Valley. Compared to the upper continental crust (UCC) tree barks are strongly enriched in Mn, Ni, Cu, Zn, Cd and Pb. To assess the degree of pollution of the different sites in the cities, a geoaccumulation index I(geo) was applied. Global pollution by V, Ni, Cr, Sb, Sn and Pb was observed in barks sampled close to traffic axes. Cr, Mo, Cd pollution principally occurred in the industrial area. A total geoaccumulation index I(GEO-tot) was defined; it is based on the total of the investigated elements and allows to evaluate the global pollution of the studied environment by assembling the I(geo) indices on a pollution map. Copyright © 2011 Elsevier Ltd. All rights reserved.

Trees in Urban and City Environments: a review of the selection criteria with particular reference to nature conservation in New Zealand Cities

Directory of Open Access Journals (Sweden)

(Late David Given

2008-07-01

Full Text Available The overall aim of this research was to review the general criteria for selection of trees for urban environments and city environments. The reason for this research was to assess the extent to which criteria for tree selection can contribute to nature conservation in cities. We conducted an extensive review of the literature, looking for publications about the selection criteria. In particular, we looked for any previous published reviews of the criteria. With reference to the criteria used in New Zealand, we undertook an unstructured review of the practices adopted in most cities. A review of the literature revealed many publications about different criteria but only one publication in which there was a general review of the criteria used for selecting trees for urban environments. By way of contrast, lists of tree species deemed to be suitable (or unsuitable for urban planting are widely available, and some include information about selection criteria, but often with little background explanation. Worldwide, commonly used criteria included commercial availability of species, compatibility with urban environments, landscape design, low maintenance, avoidance of nuisance factors and historical practice. The most common criteria are concerned with the concept of choosing species compatible with local climate and soils. Anecdotal evidence suggests that more and more cities are using a mix of criteria including those that may contribute to conservation and restoration of native biota. We suggest that there should be greater use of ecological, genetic and biogeographical criteria to meet the needs of nature conservation in New Zealand cities.

Performativity and the project: enacting urban transport security in Europe

NARCIS (Netherlands)

Hoijtink, M.

2015-01-01

In April 2011, a large consortium of European rail and security suppliers, transport operators and research organisations launched the Secured Urban Transportation - European Demonstration (SECUR-ED) project with the objective of providing public transport operators with the means to enhance urban

Monitoring Million Trees LA: Tree performance during the early years and future benefits

Science.gov (United States)

E. Gregory McPherson

2014-01-01

Million Trees LA (MTLA) is one of several large-scale mayoral tree planting initiatives striving to create more livable cities through urban forestry. This study combined field sampling of tree survival and growth with numerical modeling of future benefits to assess performance of MTLA plantings. From 2006 to 2010 MTLA planted a diverse mix of 91,786 trees....

Projecting range-wide sun bear population trends using tree cover and camera-trap bycatch data.

Directory of Open Access Journals (Sweden)

Lorraine Scotson

Full Text Available Monitoring population trends of threatened species requires standardized techniques that can be applied over broad areas and repeated through time. Sun bears Helarctos malayanus are a forest dependent tropical bear found throughout most of Southeast Asia. Previous estimates of global population trends have relied on expert opinion and cannot be systematically replicated. We combined data from 1,463 camera traps within 31 field sites across sun bear range to model the relationship between photo catch rates of sun bears and tree cover. Sun bears were detected in all levels of tree cover above 20%, and the probability of presence was positively associated with the amount of tree cover within a 6-km2 buffer of the camera traps. We used the relationship between catch rates and tree cover across space to infer temporal trends in sun bear abundance in response to tree cover loss at country and global-scales. Our model-based projections based on this "space for time" substitution suggested that sun bear population declines associated with tree cover loss between 2000-2014 in mainland southeast Asia were ~9%, with declines highest in Cambodia and lowest in Myanmar. During the same period, sun bear populations in insular southeast Asia (Malaysia, Indonesia and Brunei were projected to have declined at a much higher rate (22%. Cast forward over 30-years, from the year 2000, by assuming a constant rate of change in tree cover, we projected population declines in the insular region that surpassed 50%, meeting the IUCN criteria for endangered if sun bears were listed on the population level. Although this approach requires several assumptions, most notably that trends in abundance across space can be used to infer temporal trends, population projections using remotely sensed tree cover data may serve as a useful alternative (or supplement to expert opinion. The advantages of this approach is that it is objective, data-driven, repeatable, and it requires that

City of Berkeley, California Municipal Tree Resource Analysis

Science.gov (United States)

S.E. Maco; E.G. McPherson; J.R. Simpson; P.J. Peper; Q. Xiao

2005-01-01

Vibrant, renowned for its livability and cultural wealth, the city of Berkeley maintains trees as an integral component of the urban infrastructure. Research indicates that healthy trees can mitigate impacts associated with the built environment by reducing stormwater runoff, energy consumption, and air pollutants. Put simply, trees improve urban life, making Berkeley...

Assessment of the urban trees health status on the base of nutrient and pigment content in their leaves

Directory of Open Access Journals (Sweden)

SLAVEYA PETROVA

2014-04-01

Full Text Available Town settlements have different load level by emissions originated mostly from transport, industry and heating system. Their environmental and climate conditions are more or less changed that effect to growth, physiology and vigor of woody plants at the city public vegetation areas. Our study on determining the impact of urban environment on the tree health status was focused on the quantities of nutrients and main components of the pigment complex – chlorophyll a, chlorophyll b and carotenoids. Leaves of Acer platanoides L., Aesculus hippocastanum L. and Betula pendula Roth. were sampled from urban areas with different type of anthropogenic pressure in the town of Plovdiv (Bulgaria. Concentrations of the elements Ca, K, Mg, N, Na, P, and S were analyzed by ICP-MS. Health condition of trees in the city parks and suburban areas was acceptable, but in the central part and close to the industrial area it was non-satisfactory. This preliminary research pointed ecophysiological tools as useful to develop new criteria for sustainable urban arboriculture, including species selection (based on stress tolerance criteria, nursery hardening and preconditioning, and care after planting.

GEOMETRIC MODELLING OF TREE ROOTS WITH DIFFERENT LEVELS OF DETAIL

Directory of Open Access Journals (Sweden)

J. I. Guerrero Iñiguez

2017-09-01

Full Text Available This paper presents a geometric approach for modelling tree roots with different Levels of Detail, suitable for analysis of the tree anchoring, potentially occupied underground space, interaction with urban elements and damage produced and taken in the built-in environment. Three types of tree roots are considered to cover several species: tap root, heart shaped root and lateral roots. Shrubs and smaller plants are not considered, however, a similar approach can be considered if the information is available for individual species. The geometrical approach considers the difficulties of modelling the actual roots, which are dynamic and almost opaque to direct observation, proposing generalized versions. For each type of root, different geometric models are considered to capture the overall shape of the root, a simplified block model, and a planar or surface projected version. Lower detail versions are considered as compatibility version for 2D systems while higher detail models are suitable for 3D analysis and visualization. The proposed levels of detail are matched with CityGML Levels of Detail, enabling both analysis and aesthetic views for urban modelling.

Geometric Modelling of Tree Roots with Different Levels of Detail

Science.gov (United States)

Guerrero Iñiguez, J. I.

2017-09-01

This paper presents a geometric approach for modelling tree roots with different Levels of Detail, suitable for analysis of the tree anchoring, potentially occupied underground space, interaction with urban elements and damage produced and taken in the built-in environment. Three types of tree roots are considered to cover several species: tap root, heart shaped root and lateral roots. Shrubs and smaller plants are not considered, however, a similar approach can be considered if the information is available for individual species. The geometrical approach considers the difficulties of modelling the actual roots, which are dynamic and almost opaque to direct observation, proposing generalized versions. For each type of root, different geometric models are considered to capture the overall shape of the root, a simplified block model, and a planar or surface projected version. Lower detail versions are considered as compatibility version for 2D systems while higher detail models are suitable for 3D analysis and visualization. The proposed levels of detail are matched with CityGML Levels of Detail, enabling both analysis and aesthetic views for urban modelling.

Tree and impervious cover change in U.S

Science.gov (United States)

David J. Nowak; Eric J. Greenfield

2012-01-01

Paired aerial photographs were interpreted to assess recent changes in tree, impervious and other cover types in 20 U.S. cities as well as urban land within the conterminous United States. National results indicate that tree cover in urban areas of the United States is on the decline at a rate of about 7900 ha/yr or 4.0 million trees per year. Tree cover in 17 of the...

A collaborative archaeological research and conservation project for Moriori carved trees (rakau momori), Rekohu (Chatham Island)

International Nuclear Information System (INIS)

Barber, I.; Maxwell, J.

2011-01-01

In January-February 2010 a conservation and site-recording project began on Rekohu (Chatham Island) to locate, assess and digitally scan archaeological carved trees known as rakau momori ('dendroglyphs'). This paper briefly considers earlier work on carved trees before reporting preliminary and anticipated outcomes from our recent collaborative rakau momori archaeological project. 14 refs., 9 figs., 2 tabs.

Biological and environmental controls on tree transpiration in a suburban landscape

Science.gov (United States)

Peters, Emily B.; McFadden, Joseph P.; Montgomery, Rebecca A.

2010-12-01

Tree transpiration provides a variety of ecosystem services in urban areas, including amelioration of urban heat island effects and storm water management. Tree species vary in the magnitude and seasonality of transpiration owing to differences in physiology, response to climate, and biophysical characteristics, thereby complicating efforts to manage evapotranspiration at city scales. We report sap flux measurements during the 2007 and 2008 growing seasons for dominant tree species in a suburban neighborhood of Minneapolis-Saint Paul, Minnesota, USA. Evergreen needleleaf trees had significantly higher growing season means and annual transpiration per unit canopy area (1.90 kg H2O m-2 d-1 and 307 kg H2O m-2 yr-1, respectively) than deciduous broadleaf trees (1.11 kg H2O m-2 d-1 and 153 kg H2O m-2 yr-1, respectively) because of a smaller projected canopy area (31.1 and 73.6 m2, respectively), a higher leaf area index (8.8 and 5.5 m2 m-2, respectively), and a longer growth season (8 and 4 months, respectively). Measurements also showed patterns consistent with the species' differences in xylem anatomy (conifer, ring porous, and diffuse porous). As the growing season progressed, conifer and diffuse porous genera had increased stomatal regulation to high vapor pressure deficit, while ring porous genera maintained greater and more constant stomatal regulation. These results suggest that evaporative responses to climate change in urban ecosystems will depend in part on species composition. Overall, plant functional type differences in canopy structure and growing season length were most important in explaining species' differences in midsummer and annual transpiration, offering an approach to predicting the evapotranspiration component of urban water budgets.

Urban CO2 emissions metabolism: The Hestia Project

Science.gov (United States)

Gurney, K. R.; Razlivanov, I.; Zhou, Y.; Song, Y.

2011-12-01

A central expression of urban metabolism is the consumption of energy and the resulting environmental impact, particularly the emission of CO2 and other greenhouse gases. Quantification of energy and emissions has been performed for numerous cities but rarely has this been done in explicit space/time detail. Here, we present the Hestia Project, an effort aimed at building a high resolution (eg. building and road link-specific, hourly) fossil fuel CO2 emissions data product for the urban domain. A complete data product has been built for the city of Indianapolis and work is ongoing for the city of Los Angeles (Figure 1). The effort in Indianapolis is now part of a larger effort aimed at a convergent top-down/bottom-up assessment of greenhouse gas emissions, called INFLUX. Our urban-level quantification relies on a mixture of data and modeling structures. We start with the sector-specific Vulcan Project estimate at the mix of geocoded and county-wide levels. The Hestia aim is to distribute the Vulcan result in space and time. Two components take the majority of effort: buildings and onroad emissions. For the buildings, we utilize an energy building model which we constrain through lidar data, county assessor parcel data and GIS layers. For onroad emissions, we use a combination of traffic data and GIS road layers maintaining vehicle class information. Finally, all pointwise data in the Vulcan Project are transferred to our urban landscape and additional time distribution is performed. A key benefit of the approach taken in this study is the tracking and archiving of fuel and process-level detail (eg. combustion process, other pollutants), allowing for a more thorough understanding and analysis of energy throughputs in the urban environment. Next steps in this research from the metabolism perspective is to consider the carbon footprint of material goods and their lateral transfer in addition to the connection between electricity consumption and production.

Global Rural-Urban Mapping Project (GRUMP), Alpha Version

Data.gov (United States)

National Aeronautics and Space Administration — The Global Rural-Urban Mapping Project (GRUMP), Alpha Version consists of estimates of human population for the years 1990, 1995, and 2000 by 30 arc-second (1km)...

The accuracy of matrix population model projections for coniferous trees in the Sierra Nevada, California

Science.gov (United States)

van Mantgem, P.J.; Stephenson, N.L.

2005-01-01

1 We assess the use of simple, size-based matrix population models for projecting population trends for six coniferous tree species in the Sierra Nevada, California. We used demographic data from 16 673 trees in 15 permanent plots to create 17 separate time-invariant, density-independent population projection models, and determined differences between trends projected from initial surveys with a 5-year interval and observed data during two subsequent 5-year time steps. 2 We detected departures from the assumptions of the matrix modelling approach in terms of strong growth autocorrelations. We also found evidence of observation errors for measurements of tree growth and, to a more limited degree, recruitment. Loglinear analysis provided evidence of significant temporal variation in demographic rates for only two of the 17 populations. 3 Total population sizes were strongly predicted by model projections, although population dynamics were dominated by carryover from the previous 5-year time step (i.e. there were few cases of recruitment or death). Fractional changes to overall population sizes were less well predicted. Compared with a null model and a simple demographic model lacking size structure, matrix model projections were better able to predict total population sizes, although the differences were not statistically significant. Matrix model projections were also able to predict short-term rates of survival, growth and recruitment. Mortality frequencies were not well predicted. 4 Our results suggest that simple size-structured models can accurately project future short-term changes for some tree populations. However, not all populations were well predicted and these simple models would probably become more inaccurate over longer projection intervals. The predictive ability of these models would also be limited by disturbance or other events that destabilize demographic rates. ?? 2005 British Ecological Society.

Institutional interventions in complex urban systems: Coping with boundary issues in urban planning projects

NARCIS (Netherlands)

S. Verweij (Stefan); I.F. van Meerkerk (Ingmar); J.F.M. Koppenjan (Joop); H. Geerlings (Harry)

2014-01-01

markdownabstract__Abstract__ Urban planning projects are planned and organized through arrangements between actors. These arrangements are institutional interventions: they intervene in the institutional landscape as existing organizational boundaries are (temporarily) redrawn. Such boundary

Global Rural-Urban Mapping Project, Version 1 (GRUMPv1): Urban Extent Polygons, Revision 01

Data.gov (United States)

National Aeronautics and Space Administration — The primary output of the Global Rural Urban Mapping Project, Version 1 (GRUMPv1) are a series of grids representing estimated population counts and density for the...

Gainesville's urban forest canopy cover

Science.gov (United States)

Francisco Escobedo; Jennifer A. Seitz; Wayne Zipperer

2009-01-01

Ecosystem benefits from trees are linked directly to the amount of healthy urban forest canopy cover. Urban forest cover is dynamic and changes over time due to factors such as urban development, windstorms, tree removals, and growth. The amount of a city's canopy cover depends on its land use, climate, and people's preferences. This fact sheet examines how...

Factors affecting long-term mortality of residential shade trees: evidence from Sacramento, California

Science.gov (United States)

Yekang Ko; Jun-Hak Lee; E. Gregory McPherson; Lara A. Roman

2015-01-01

Urban tree survival is essential to sustain the ecosystem services of urban forests and monitoring is needed to accurately assess benefits. While some urban forestry studies have reported street tree survival, little is known about the factors influencing residential yard tree survival, especially over the long-term. We assessed residential shade tree survival in...

A framework for adapting urban forests to climate change

Science.gov (United States)

Leslie Brandt; Abigail Derby Lewis; Robert Fahey; Lydia Scott; Lindsay Darling; Chris Swanston

2016-01-01

Planting urban trees and expanding urban forest canopy cover are often considered key strategies for reducing climate change impacts in urban areas. However, urban trees and forests can also be vulnerable to climate change through shifts in tree habitat suitability, changes in pests and diseases, and changes in extreme weather events. We developed a three-step...

Relationship Between Mycorrhizal Associations and Tree Phyto-Sanitary Conditions of Urban Woodlands of Bogota D.C., Colombia

International Nuclear Information System (INIS)

Ramos Montano, Carolina; Posada Almanza, Raul H; Ronderos Figueroa, Miguel A; Penagos Canon, Gustavo A

2010-01-01

Spore number and root infection by Arbuscular mycorrhizal fungi were evaluated in Eugenia myrtifolia, Ficus soatensis and Croton bogotensis, in parks and green zones of urban woodlands of Bogota D.C, Colombia. The aim was to investigate relations between mycorrhizal associations and tree phyto-sanitary conditions, and effects of two distinct climatic zones. It was demonstrated that plant species and climate are significant sources of variations in the general mycorrhizal state. Eugenia myrtifolia showed the highest degree of root colonization but the lowest number of spores, while C. bogotensis had the opposite response. In general, dry environments favored the mycorrhizal infection levels. By considering overall data, there was a positive relation between the general phytosanitary status of the urban trees and the mycorrhizal colonization. The evaluation of the relationship with the incidence of specific foliar symptoms showed that chlorosis, bight and herbivory maintained a negative relation with the mycorrhization in E. myrtifolia and C. bogotensis. Results suggest that association with AM fungi helps in any way for reducing

Urban trees and forests of the Chicago region

Science.gov (United States)

David J. Nowak; Robert E. III Hoehn; Allison R. Bodine; Daniel E. Crane; John F. Dwyer; Veta Bonnewell; Gary Watson

2013-01-01

An analysis of trees in the Chicago region of Illinois reveals that this area has about 157,142,000 trees with tree and shrub canopy that covers 21.0 percent of the region. The most common tree species are European buckthorn, green ash, boxelder, black cherry, and American elm. Trees in the Chicago region currently store about 16.9 million tons of carbon (61.9 million...

Tree cover and aridity projections to 2060: a technical document supporting the Forest Service 2010 RPA assessment

Science.gov (United States)

Eric J. Greenfield; David J. Nowak

2013-01-01

Future projections of tree cover and climate change are useful to natural resource managers as they illustrate potential changes to our natural resources and the ecosystem services they provide. This report a) details three projections of tree cover change across the conterminous United States based on predicted land-use changes from 2000 to 2060; b) evaluates nine...

Brand Awareness Strategy for Fashion Urban Youth Local Brand "Pinx Project"

OpenAIRE

Insania, Rima; Mutiaz, Intan Rizky

2013-01-01

Indonesian young designers have a very strong potential to explore the International level with the achievements that gradually starts to open the eyes of the global fashion world.urban youth local label movement which spreading in 5 years, glance Indonesia fashion industry. One of the is Pinx Project. Pinx Project, found in late November 2011, grew along with urban youth fashion which was booming among young people and many other emerging fashion lines. Pinx, which can still be considered as...

Passive control potentials of trees and on-street parked cars in reduction of air pollution exposure in urban street canyons

International Nuclear Information System (INIS)

Abhijith, K.V.; Gokhale, Sharad

2015-01-01

This study investigates the passive-control-potentials of trees and on-street parked cars on pedestrian exposure to air pollutants in a street canyon using three-dimensional CFD. Since, according to some studies trees deteriorate air quality and cars parked roadside improve it, the combine as well as separate effects of trees and on-street parked cars have been examined. For this, different tree canopy layouts and parking configurations have been developed and pedestrian exposure for each has been analysed. The results showed, for example, tree crown with high porosity and low-stand density in combination with parallel or perpendicular car parking reduced the pedestrian exposure considerably. - Highlights: • Trees and on-street parked cars can manipulate pollutant levels in street canyons. • Low stand density trees with 0° or 90° car parking reduce pedestrian exposure. • Trees with medium crown, high porosity, low stand density reduce pollutant levels. - This study investigated the combination of trees and on-street parked cars to manipulate pollutant levels in urban street canyons to reduce pedestrian exposure

Management of Stakeholders in Urban Regeneration Projects. Case Study: Baia-Mare, Transylvania

Directory of Open Access Journals (Sweden)

Corina M. Rădulescu

2016-03-01

Full Text Available The process of regeneration of abandoned areas or deteriorated structures in the cities of Romania has become a strategy of urban-integrated development. Conversions and/or regeneration of facilities in the form of assets, with different destinations, are part of the new trend of urban regeneration and a strategy used to attract investment capital. The disappearance of mining industry sites in Maramures County, Romania, has allowed the expansion and planning of new spaces for public use and/or semipublic, and most cities have opened new development perspectives. The study is based on empirical research conducted on the brownfields of Baia-Mare City. This research investigates how stakeholders of an urban regeneration project can be more actively involved in the decision-making processes with regard to the strategic elements of the renewal project of Cuprom, as a former mining industry area. This research contributes to the development of the investigation of new types of knowledge of stakeholder analysis and improves the available practices for stakeholder salience. Social networks created and consolidated by stakeholders of an urban regeneration project are the object of analysis, evaluation, and monitoring of the equilibrium between project management and grant of resources and capital. This paper studies the salience of stakeholders of the SEPA-CUPROM project from Baia-Mare using the social networking approach. Visualization by graphical methods of social networking analysis is a useful instrument in the decision-making process of brownfield projects as part of sustainable strategies in Romania.

EFFECTIVENESS OF LARGE WOODY DEBRIS IN STREAM REHABILITATION PROJECTS IN URBAN BASINS. (R825284)

Science.gov (United States)

Urban stream rehabilitation projects commonly include log placement to establish the types of habitat features associated with large woody debris (LWD) in undisturbed streams. Six urban in-stream rehabilitation projects were examined in the Puget Sound Lowland of western Washi...

Effects of trees on mean wind, turbulence and momentum exchange within and above a real urban environment

Science.gov (United States)

Giometto, M. G.; Christen, A.; Egli, P. E.; Schmid, M. F.; Tooke, R. T.; Coops, N. C.; Parlange, M. B.

2017-08-01

Large-eddy simulations (LES) are used to gain insight into the effects of trees on turbulence, aerodynamic parameters, and momentum transfer rates characterizing the atmosphere within and above a real urban canopy. Several areas are considered that are part of a neighborhood in the city of Vancouver, BC, Canada where a small fraction of trees are taller than buildings. In this area, eight years of continuous wind and turbulence measurements are available from a 30 m meteorological tower. Data from airborne light detection and ranging (LiDAR) are used to represent both buildings and vegetation at the LES resolution. In the LES algorithm, buildings are accounted through an immersed boundary method, whereas vegetation is parameterized via a location-specific leaf area density. LES are performed including and excluding vegetation from the considered urban areas, varying wind direction and leaf area density. Surface roughness lengths (z0) from both LES and tower measurements are sensitive to the 0 ≤ LAI /λfb lower than the 27% increase featured by LES for the most representative canopy (leaves-off LAI / λfSUP>b = 0.74 , leaves-on LAI /λfb = 2.24). Removing vegetation from such a canopy would cause a dramatic drop of approximately 50% in z0 when compared to the reference summer value. The momentum displacement height (d) from LES also consistently increases as LAI / λfb increases, due in large part to the disproportionate amount of drag that the (few) relatively taller trees exert on the flow. LES and measurements both predict an increase in the ratio of turbulent to mean kinetic energy (TKE/MKE) at the tower sampling height going from winter to summer, and LES also show how including vegetation results in a more (positive) negatively skewed (horizontal) vertical velocity distribution - reflecting a more intermittent velocity field which favors sweep motions when compared to ejections. Within the urban canopy, the effects of trees are twofold: on one hand, they act

Responses of gas-exchange rates and water relations to annual fluctuations of weather in three species of urban street trees.

Science.gov (United States)

Osone, Yoko; Kawarasaki, Satoko; Ishida, Atsushi; Kikuchi, Satoshi; Shimizu, Akari; Yazaki, Kenichi; Aikawa, Shin-Ichi; Yamaguchi, Masahiro; Izuta, Takeshi; Matsumoto, Genki I

2014-10-01

The frequency of extreme weather has been rising in recent years. A 3-year study of street trees was undertaken in Tokyo to determine whether: (i) street trees suffer from severe water stress in unusually hot summer; (ii) species respond differently to such climatic fluctuations; and (iii) street trees are also affected by nitrogen (N) deficiency, photoinhibition and aerosol pollution. During the study period (2010-12), midsummers of 2010 and 2012 were unusually hot (2.4-2.8 °C higher maximum temperature than the long-term mean) and dry (6-56% precipitation of the mean). In all species, street trees exhibited substantially decreased photosynthetic rate in the extremely hot summer in 2012 compared with the average summer in 2011. However, because of a more conservative stomatal regulation (stomatal closure at higher leaf water potential) in the hot summer, apparent symptoms of hydraulic failure were not observed in street trees even in 2012. Compared with Prunus × yedoensis and Zelkova serrata, Ginkgo biloba, a gymnosperm, was high in stomatal conductance and midday leaf water potential even under street conditions in the unusually hot summer, suggesting that the species had higher drought resistance than the other species and was less susceptible to urban street conditions. This lower susceptibility might be ascribed to the combination of higher soil-to-leaf hydraulic conductance and more conservative water use. Aside from meteorological conditions, N deficiency affected street trees significantly, whereas photoinhibition and aerosol pollution had little effect. The internal CO2 and δ(13)C suggested that both water and N limited the net photosynthetic rate of street trees simultaneously, but water was more limiting. From these results, we concluded that the potential risk of hydraulic failure caused by climatic extremes could be low in urban street trees in temperate regions. However, the size of the safety margin might be different between species. © The

Assessing urban forest effects and values: Toronto's urban forest

Science.gov (United States)

David J. Nowak; Robert E. III Hoehn; Allison R. Bodine; Eric J. Greenfield; Alexis Ellis; Theodore A. Endreny; Yang Yang; Tian Zhou; Ruthanne. Henry

2013-01-01

An analysis of trees in Toronto, Ontario, reveals that this city has about 10.2 million trees with a tree and shrub canopy that covers approximately 26.6 percent of the city. The most common tree species are eastern white-cedar, sugar maple, and Norway maple. The urban forest currently stores an estimated 1.1 million metric tons of carbon valued at CAD$25.0 million. In...

Urban Forest Ecosystem Service Optimization, Tradeoffs, and Disparities

Science.gov (United States)

Bodnaruk, E.; Kroll, C. N.; Endreny, T. A.; Hirabayashi, S.; Yang, Y.

2014-12-01

Urban land area and the proportion of humanity living in cities is growing, leading to increased urban air pollution, temperature, and stormwater runoff. These changes can exacerbate respiratory and heat-related illnesses and affect ecosystem functioning. Urban trees can help mitigate these threats by removing air pollutants, mitigating urban heat island effects, and infiltrating and filtering stormwater. The urban environment is highly heterogeneous, and there is no tool to determine optimal locations to plant or protect trees. Using spatially explicit land cover, weather, and demographic data within biophysical ecosystem service models, this research expands upon the iTree urban forest tools to produce a new decision support tool (iTree-DST) that will explore the development and impacts of optimal tree planting. It will also heighten awareness of environmental justice by incorporating the Atkinson Index to quantify disparities in health risks and ecosystem services across vulnerable and susceptible populations. The study area is Baltimore City, a location whose urban forest and environmental justice concerns have been studied extensively. The iTree-DST is run at the US Census block group level and utilizes a local gradient approach to calculate the change in ecosystem services with changing tree cover across the study area. Empirical fits provide ecosystem service gradients for possible tree cover scenarios, greatly increasing the speed and efficiency of the optimization procedure. Initial results include an evaluation of the performance of the gradient method, optimal planting schemes for individual ecosystem services, and an analysis of tradeoffs and synergies between competing objectives.

Public-private partnerships in urban regeneration projects: Organizational form or managerial capacity?

NARCIS (Netherlands)

M.B. Kort (Michiel); E-H. Klijn (Erik-Hans)

2011-01-01

markdownabstract__Abstract__ Urban regeneration companies (URCs) are public-private entities appearing across Europe. They are created specifically to manage and implement more effectively urban regeneration projects. Core ideas behind the establishment of these newly emerging partnerships aim to

Evaluation of Urban Planning Projects Criteria Using Fuzzy AHP Technique

Directory of Open Access Journals (Sweden)

Walid Mustafa Kamas

2017-05-01

Full Text Available In this research, Fuzzy Analytic Hierarchy Process technique is applied (Fuzzy AHP which is one of multi-criteria decision making techniques to evaluate the criteria for urban planning projects, the project of developing master plan of Al-Muqdadiyah city to 2035 has been chosen as a case study. The researcher prepared a list of criteria in addition to the authorized departments criteria and previous researches in order to choose optimized master plan according to these criteria. This research aims at employing the foundations of (Fuzzy AHP technique in evaluating urban planning criteria precisely and flexible. The results of the data analysis to the individuals of the sample who are specialists, in this aspect. The land use criteria are more important than the rest of the criteria in these projects, where it received the relative importance with percentile (42.1 %.

Releases of a natural flightless strain of the ladybird beetle Adalia bipunctata reduce aphid-born honeydew beneath urban lime trees

NARCIS (Netherlands)

Lommen, S.T.E.; Holness, T.C.; Kuik, van A.J.; Jong, de P.W.; Brakefield, P.M.

2013-01-01

Aphids can cause major environmental problems in urban areas. One important problem is the annual outbreaks of lime aphid, Eucallipterus tiliae (L.) (Hemiptera: Aphididae), which spoil the surroundings of lime trees by depositing honeydew. To date no environmentally friendly method has been

URBAN FORESTRY AND ITS PRACTICES IN ARTVIN

Directory of Open Access Journals (Sweden)

Sinan Güner

2008-04-01

Full Text Available Urban population expansion is taking place most rapidly in Turkey, and cities are experiencing some serious problems: deterioration of air quality, higher air temperatures, increased noise levels, greater psychological stress and a decreased sense of community. Urban forests are all the trees and other vegetation growing in and close to urban areas, and it should be managed for their economic, environmental and social benefits. The amount, type, location and condition of urban vegetation directly affect the amount of benefits derived from the vegetation and their associated costs. Trees and green spaces help keep cities cool, act as natural filters and noise absorbers; improve microclimates and protect and improve the quality of natural resources, including soil, water, vegetation and wildlife. Trees contribute significantly to the aesthetic appeal of cities, thereby helping to maintain the psychological health of their inhabitants. Beyond ecological and aesthetic benefits, urban forestry has a role in helping resource-poor populations meet basic needs, particularly but not exclusively in developing countries. The city of Artvin isn’t rich in urban trees which are those in street trees and in local parks but rich in those along greenspace areas around city. But, trees and green spaces didn’t play an important role in improving city living conditions. Thus, urban forests in Artvin should become an integral part of the efforts to improve the quality of life in Artvin. Forest General Directorate established an “urban forest” in Artvin in 2006 and this area contains more than 95 plant species.

Implementation of visitor pattern in processing a syntax tree in Qlab project

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Đenić Aleksandar

2012-01-01

Full Text Available Qlab is an open-source project that supports various mathematical calculations, specialized for academic use. It has been developed at the Faculty of Mathematics, University of Belgrade, and is supported by Microsoft Serbia. In this paper we present some of Qlab’s successfully implemented core solutions. More precisely, in our approach we use a specialized Visitor pattern to optimize the management of syntax tree commands that our parser sends to our engine. This allows the processing of a larger scale of tree implementation using the Visitor interface.

Private Sector-led Urban Development Projects. Management, Partnerships and Effects in the Netherlands and the UK

OpenAIRE

Erwin Heurkens

2012-01-01

Central to this research lays the concept of private sector-led urban development projects (Heurkens, 2010). Such projects involve project developers taking a leading role and local authorities adopting a facilitating role, in managing the development of an urban area, based on a clear public-private role division. Such a development strategy is quite common in Anglo-Saxon urban development practices, but is less known in Continental European practices. Nonetheless, since the beginning of the...

Urban High School Student Engagement through CincySTEM iTEST Projects

Science.gov (United States)

Beckett, Gulbahar H.; Hemmings, Annette; Maltbie, Catherine; Wright, Kathy; Sherman, Melissa; Sersion, Brian

2016-01-01

This paper focuses on the notable heightening of underrepresented students' engagement in STEM education through project-based learning CincySTEM iTEST projects. The projects, funded by an iTEST NSF grant, were designed and facilitated by teachers at a new STEM urban public high school serving low-income African-American students. Student…

A review of tree root conflicts with sidewalks, curbs, and roads

Science.gov (United States)

T.B. Randrup; E.G. McPherson; L.R. Costello

2003-01-01

Literature relevant to tree root and urban infrastructure conflicts is reviewed. Although tree roots can conflict with many infrastructure elements, sidewalk and curb conflicts are the focus of this review. Construction protocols, urban soils, root growth, and causal factors (soil conditions, limited planting space, tree size, variation in root architecture, management...

Responses of Sap Flux Density to Changing Atmospheric Humidity in Three Common Street Tree Species in Bangkok, Thailand

Directory of Open Access Journals (Sweden)

Pantana Tor-ngern

2016-09-01

Full Text Available Efficient water management in urban landscape is imperative under the projected increases in drought stress under future climate. Because different tree species have different stomatal regulations to prevent water loss under water limitation, comparative study of species-specific responses of water use to changing weather conditions will benefit selective planting of urban trees for sustainable urban greening management. Here, we performed a simple and short-term investigation of water use characteristics of three common street tree species in Bangkok, a major city in Southeast Asia. Species included Pterocarpus indicus (Pi, Swietenia macrophylla (Sm and Lagerstroemia speciosa (Ls. We used self-constructed heat dissipation probes to track water uptake rates, expressed as sap flux density (JS, in stems of potted trees and examined their diurnal variations with changing atmospheric humidity, represented by vapor pressure deficit (D. The results implied that two of the three species: Pi and Sm, may be selected for planting because their Js was less sensitive to changing D compared to Ls. The sap flux density of Ls increased more rapidly with rising D, implying higher sensitivity to drought in Ls, compared to the other two species. Nevertheless, further study on large trees and under longer period of investigation, covering both dry and wet seasons, is required to confirm this finding.

Estimating the influence of different urban canopy cover types on atmospheric particulate matter (PM10) pollution abatement in London UK.

Science.gov (United States)

Tallis, Matthew; Freer-Smith, Peter; Sinnett, Danielle; Aylott, Matthew; Taylor, Gail

2010-05-01

In the urban environment atmospheric pollution by PM10 (particulate matter with a diameter less than 10 x 10-6 m) is a problem that can have adverse effects on human health, particularly increasing rates of respiratory disease. The main contributors to atmospheric PM10 in the urban environment are road traffic, industry and power production. The urban tree canopy is a receptor for removing PM10s from the atmosphere due to the large surface areas generated by leaves and air turbulence created by the structure of the urban forest. In this context urban greening has long been known as a mechanism to contribute towards PM10 removal from the air, furthermore, tree canopy cover has a role in contributing towards a more sustainable urban environment. The work reported here has been carried out within the BRIDGE project (SustainaBle uRban plannIng Decision support accountinG for urban mEtabolism). The aim of this project is to assess the fluxes of energy, water, carbon dioxide and particulates within the urban environment and develope a DSS (Decision Support System) to aid urban planners in sustainable development. A combination of published urban canopy cover data from ground, airborne and satellite based surveys was used. For each of the 33 London boroughs the urban canopy was classified to three groups, urban woodland, street trees and garden trees and each group quantified in terms of ground cover. The total [PM10] for each borough was taken from the LAEI (London Atmospheric Emissions Inventory 2006) and the contribution to reducing [PM10] was assessed for each canopy type. Deposition to the urban canopy was assessed using the UFORE (Urban Forest Effects Model) approach. Deposition to the canopy, boundary layer height and percentage reduction of the [PM10] in the atmosphere was assessed using both hourly meterological data and [PM10] and seasonal data derived from annual models. Results from hourly and annual data were compared with measured values. The model was then

Exploiting Earth observation data pools for urban analysis: the TEP URBAN project

Science.gov (United States)

Heldens, W.; Esch, T.; Asamer, H.; Boettcher, M.; Brito, F.; Hirner, A.; Marconcini, M.; Mathot, E.; Metz, A.; Permana, H.; Zeidler, J.; Balhar, J.; Soukop, T.; Stankek, F.

2017-10-01

Large amounts of Earth observation (EO) data have been collected to date, to increase even more rapidly with the upcoming Sentinel data. All this data contains unprecedented information, yet it is hard to retrieve, especially for nonremote sensing specialists. As we live in an urban era, with more than 50% of the world population living in cities, urban studies can especially benefit from the EO data. Information is needed for sustainable development of cities, for the understanding of urban growth patterns or for studying the threats of natural hazards or climate change. Bridging this gap between the technology-driven EO sector and the information needs of environmental science, planning, and policy is the driver behind the TEP-Urban project. Modern information technology functionalities and services are tested and implemented in the Urban Thematic Exploitation Platform (U-TEP). The platform enables interested users to easily exploit and generate thematic information on the status and development of the environment based on EO data and technologies. The beta version of the web platform contains value added basic earth observation data, global thematic data sets, and tools to derive user specific indicators and metrics. The code is open source and the architecture of the platform allows adding of new data sets and tools. These functionalities and concepts support the four basic use scenarios of the U-TEP platform: explore existing thematic content; task individual on-demand analyses; develop, deploy and offer your own content or application; and, learn more about innovative data sets and methods.

The tree BVOC index

Science.gov (United States)

J.R. Simpson; E.G. McPherson

2011-01-01

Urban trees can produce a number of benefits, among them improved air quality. Biogenic volatile organic compounds (BVOCs) emitted by some species are ozone precursors. Modifying future tree planting to favor lower-emitting species can reduce these emissions and aid air management districts in meeting federally mandated emissions reductions for these compounds. Changes...

Should we plant trees to offset greenhouse gas emissions in semi-arid environments?

Science.gov (United States)

Pataki, D. E.; Pincetl, S.; Gillespie, T. W.; Li, W.; McCarthy, H. R.; Saatchi, S.; Saphores, J.

2008-12-01

Urban tree planting programs have been gaining popularity in the United States. Urban trees have been associated with a variety of environmental benefits, including improvements in air quality, mitigation of urban heat island effects, reductions in stormwater runoff, and more recently, carbon sequestration. There are also other potential aesthetic and economic benefits of urban forests, which have been shown to affect real estate values. However, there may also be significant economic and environmental costs of planting and maintaining trees in urban areas, particularly in semi-arid environments where trees are not native and require irrigation and fertilization. We are conducting an analysis of the Million Tree Initiative in the city of Los Angeles, which has committed to a major tree planting program. Los Angeles currently has a low tree canopy cover relative to other cities, particularly in its low income neighborhoods. We are evaluating the decision-making processes associated with the new tree planting program, its perceived benefits, and its actual benefits based on measurements of plant and ecosystem processes such as transpiration, photosynthesis, and water use efficiency; remote sensing analyses of tree cover and surface temperature; and economic analyses. We have found great variability in the interpretation of the program by its various participants, but also significant institutional learning as the program has evolved. Our datasets have challenged some of the common assumptions of the program, for example, the assumption that native species use less water than imported species and are therefore more environmentally beneficial in terms of water resources. We have also found significant impacts of the urban forest on air temperature, which may reduce energy use during the summer due to reductions in air conditioning. This is likely to be a larger effect of urban trees on greenhouse gas emissions than direct carbon sequestration alone, which is a very

Private Sector-led Urban Development Projects : Management, Partnerships & Effects in the Netherlands and the UK

NARCIS (Netherlands)

Heurkens, E.W.T.M.

2012-01-01

Subject of study is Private Sector-led Urban Development Projects. Such projects involve property developers taking a leading role and local authorities adopting a facilitating role in the management of the development of an urban area, based on a framework of public requirements and a formal

i-Tree: Tools to assess and manage structure, function, and value of community forests

Science.gov (United States)

Hirabayashi, S.; Nowak, D.; Endreny, T. A.; Kroll, C.; Maco, S.

2011-12-01

Trees in urban communities can mitigate many adverse effects associated with anthropogenic activities and climate change (e.g. urban heat island, greenhouse gas, air pollution, and floods). To protect environmental and human health, managers need to make informed decisions regarding urban forest management practices. Here we present the i-Tree suite of software tools (www.itreetools.org) developed by the USDA Forest Service and their cooperators. This software suite can help urban forest managers assess and manage the structure, function, and value of urban tree populations regardless of community size or technical capacity. i-Tree is a state-of-the-art, peer-reviewed Windows GUI- or Web-based software that is freely available, supported, and continuously refined by the USDA Forest Service and their cooperators. Two major features of i-Tree are 1) to analyze current canopy structures and identify potential planting spots, and 2) to estimate the environmental benefits provided by the trees, such as carbon storage and sequestration, energy conservation, air pollution removal, and storm water reduction. To cover diverse forest topologies, various tools were developed within the i-Tree suite: i-Tree Design for points (individual trees), i-Tree Streets for lines (street trees), and i-Tree Eco, Vue, and Canopy (in the order of complexity) for areas (community trees). Once the forest structure is identified with these tools, ecosystem services provided by trees can be estimated with common models and protocols, and reports in the form of texts, charts, and figures are then created for users. Since i-Tree was developed with a client/server architecture, nationwide data in the US such as location-related parameters, weather, streamflow, and air pollution data are stored in the server and retrieved to a user's computer at run-time. Freely available remote-sensed images (e.g. NLCD and Google maps) are also employed to estimate tree canopy characteristics. As the demand for i-Tree

Improving local air quality in cities: To tree or not to tree?

International Nuclear Information System (INIS)

Vos, Peter E.J.; Maiheu, Bino; Vankerkom, Jean; Janssen, Stijn

2013-01-01

Vegetation is often quoted as an effective measure to mitigate urban air quality problems. In this work we demonstrate by the use of computer models that the air quality effect of urban vegetation is more complex than implied by such general assumptions. By modelling a variety of real-life examples we show that roadside urban vegetation rather leads to increased pollutant concentrations than it improves the air quality, at least locally. This can be explained by the fact that trees and other types of vegetation reduce the ventilation that is responsible for diluting the traffic emitted pollutants. This aerodynamic effect is shown to be much stronger than the pollutant removal capacity of vegetation. Although the modelling results may be subject to a certain level of uncertainty, our results strongly indicate that the use of urban vegetation for alleviating a local air pollution hotspot is not expected to be a viable solution. Highlights: ► We model the impact of roadside urban vegetation on the local air quality. ► Vegetation in general lowers the wind speed thereby reducing the ventilation. ► In general roadside urban vegetation does not appear to decrease concentrations. ► Roadside urban trees have a pronounced detrimental effect on the local air quality. ► City planners and policy makers need to be better informed about this topic. -- Rather than improving the local air quality, our results suggest that roadside urban vegetation increases the pollutant concentrations at the footpath

Citizen participation, indispensable factor in the generation of urban design projects that respond to the needs of users in Mexico

Directory of Open Access Journals (Sweden)

Flavio Franco Muñoz

2015-09-01

Full Text Available The relationship between urban design projects with users, it is evident that the importance of public participation in the development of the realization and implementation of these projects; being one of the aspects that aroused the interest in developing the research project "Citizen Participation and rehabilitation of public spaces in the downtown area of Aguascalientes. The cases of Madero and Venustiano Carranza Zaragoza streets" in the which it aims to propose a model for the process of developing an urban design project that incorporates citizen participation effectively, based on the analysis of cases of Madero and Venustiano Carranza Zaragoza streets and analysis theoretical framework of the research project; This research is being done within the Doctorate of Science of the Anthropic Areas, which is being conducted at the Autonomous University of Aguascalientes. The aim expose in this paper is the importance of public participation in a key stage in the process of realization and implementation of a project of urban design, urban planning stage, to substantiate the development stage of the project design city; this proposal derived from the analysis of the knowledge acquired through the research project being conducted within the PhD. The set in our research project to develop the stages in the process of realization and implementation of an urban design project, made up, urban planning, studies to substantiate the project, zoning scheme, the draft, the project executive, project implementation and monitoring, control and evaluation of urban design project realized; allowed to establish the stages where citizen participation is essential, and these stages, identifying the aspects that will be enriched with the knowledge gained from this participation. Considering the participation of citizens from the realization of urban development programs, whether in cities, partial, sectoral or development schemes localities, allow to be

Evaluation of four methods for estimating leaf area of isolated trees

Science.gov (United States)

P.J. Peper; E.G. McPherson

2003-01-01

The accurate modeling of the physiological and functional processes of urban forests requires information on the leaf area of urban tree species. Several non-destructive, indirect leaf area sampling methods have shown good performance for homogenous canopies. These methods have not been evaluated for use in urban settings where trees are typically isolated and...

Growing Greener Cities: A Tree-Planting Handbook.

Science.gov (United States)

Moll, Gary; Young, Stanley

This step-by-step guide, developed by the Global ReLeaf organization, presents tree-planting advice and simple steps to organizing a successful community tree-planting and tree-care program. The text is divided into three parts. Part 1 introduces trees and discusses the role they play as components of the living urban environment. Distinctions are…

Structure of an urban Christmas tree market

Science.gov (United States)

Thomas H. Pendleton; Lawrence D. Garrett; Lawrence D. Garrett

1973-01-01

The retail Christmas tree market in Winston-Salem, N.C., was studied 3 years. Types of retailers and their sales are described. Best sales were made by dealers who had lots on heavily traveled streets in business districts, had ample parking facilities, advertised, and displayed their trees well.

Project CAPTURE: a U.S. national prioritization assessment of tree species for conservation, management, and restoration

Science.gov (United States)

Kevin M. Potter; Barbara S. Crane; Valerie D. Hipkins

2017-01-01

that forest tree species will undergo population-level extirpation or species-level extinction during the next century. Project CAPTURE (Conservation Assessment and Prioritization of Forest Trees Under Risk of Extirpation) is a cooperative effort across the three U.S. Department of Agriculture Forest Service (USDA FS) deputy areas to establish a framework for...

Problem Solution Project: Transforming Curriculum and Empowering Urban Students and Teachers

Science.gov (United States)

Jarrett, Olga S.; Stenhouse, Vera

2011-01-01

This article presents findings of 6 years of implementing a Problem Solution Project, an assignment influenced by service learning, problem-based learning, critical theory, and critical pedagogy whereby teachers help children tackle real problems. Projects of 135 teachers in an urban certification/master's program were summarized by cohort year…

Urban Options Solar Greenhouse Demonstration Project. Final report

Energy Technology Data Exchange (ETDEWEB)

Cipparone, L.

1980-10-15

The following are included: the design process, construction, thermal performance, horticulture, educational activities, and future plans. Included in appendices are: greenhouse blueprints, insulating curtain details, workshop schedules, sample data forms, summary of performance calculations on the Urban Options Solar Greenhouse, data on vegetable production, publications, news articles on th Solar Greenhouse Project, and the financial statement. (MHR)

Institutional conditions for sustainable private sector-led urban development projects : A conceptual model

NARCIS (Netherlands)

Heurkens, E.W.T.M.

2016-01-01

Across the globe sustainable private sector-led urban development projects (SPUDPs) in the built environment rarely commence as real estate developers face several institutional barriers which limit their capacity to develop economic-viable, social-responsible, environmental-friendly urban places.

Tree Flora of Sabah and Sarawak project – progress and future activities

NARCIS (Netherlands)

Tan, H.S.; Nadiah, I.; Eryani, S.S.

2009-01-01

Tropical forests in Borneo (Brunei Darussalam, Kalimantan, Sabah and Sarawak) are considered as one of the twelve mega biodiversity centres in the world. However, until now, there is no up-to-date or complete documentation on the flora of the island. The Tree Flora of Sabah and Sarawak Project,

Urbanization Effects on the Vertical Distribution of Soil Microbial Communities and Soil C Storage across Edge-to-Interior Urban Forest Gradients

Science.gov (United States)

Rosier, C. L.; Van Stan, J. T., II; Trammell, T. L.

2017-12-01

Urbanization alters environmental conditions such as temperature, moisture, carbon (C) and nitrogen (N) deposition affecting critical soil processes (e.g., C storage). Urban soils experience elevated N deposition (e.g., transportation, industry) and decreased soil moisture via urban heat island that can subsequently alter soil microbial community structure and activity. However, there is a critical gap in understanding how increased temperatures and pollutant deposition influences soil microbial community structure and soil C/N cycling in urban forests. Furthermore, canopy structural differences between individual tree species is a potentially important mechanism facilitating the deposition of pollutants to the soil. The overarching goal of this study is to investigate the influence of urbanization and tree species structural differences on the bacterial and fungal community and C and N content of soils experiencing a gradient of urbanization pressures (i.e., forest edge to interior; 150-m). Soil cores (1-m depth) were collected near the stem (urban pressure (i.e., forest edge). We further expect trees located on the edge of forest fragments will maintain greater surface soil (urbanization alters soil microbial community composition via reduced soil moisture and carbon storage potential via deposition gradients. Further analyses will answer important questions regarding how individual tree species alters urban soil C storage, N retention, and microbial dynamics.

IU.R Residential Urban Interfaces. Strategies and tools for a renewal project

Directory of Open Access Journals (Sweden)

Sabrina Borgianni

2012-10-01

Full Text Available In the contemporary city, quality of urban space is a key element in life quality and a driving force for the competitiveness. The increasing complexity of relationships and the evolving needs and use patterns reflect urban complexity in a corresponding physical space: the urban interface, an entity that mediates the sociospatial relationships between public and private sphere and that assumes strategic importance in redevelopment of suburbs. Research, carried out on a case ‘study project’, defines the criteria for a Residential Urban Interface approach as a tool for micro-urban redevelopment which merge into the proposed Project Plan, the metaproject field aimed at process design, space design and design of management and use scenario.

Large-Scale Urban Projects, Production of Space and Neo-liberal Hegemony: A Comparative Study of Izmir

Directory of Open Access Journals (Sweden)

Mehmet PENPECİOĞLU

2013-04-01

Full Text Available With the rise of neo-liberalism, large-scale urban projects (LDPs have become a powerful mechanism of urban policy. Creating spaces of neo-liberal urbanization such as central business districts, tourism centers, gated residences and shopping malls, LDPs play a role not only in the reproduction of capital accumulation relations but also in the shift of urban political priorities towards the construction of neo-liberal hegemony. The construction of neo-liberal hegemony and the role played by LDPs in this process could not only be investigated by the analysis of capital accumulation. For such an investigation; the role of state and civil society actors in LDPs, their collaborative and conflictual relationships should be researched and their functions in hegemony should be revealed. In the case of Izmir’s two LDPs, namely the New City Center (NCC and Inciraltı Tourism Center (ITC projects, this study analyzes the relationship between the production of space and neo-liberal hegemony. In the NCC project, local governments, investors, local capital organizations and professional chambers collaborated and disseminated hegemonic discourse, which provided social support for the project. Through these relationships and discourses, the NCC project has become a hegemonic project for producing space and constructed neo-liberal hegemony over urban political priorities. In contrast to the NCC project, the ITC project saw no collaboration between state and organized civil society actors. The social opposition against the ITC project, initiated by professional chambers, has brought legal action against the ITC development plans in order to prevent their implementation. As a result, the ITC project did not acquire the consent of organized social groups and failed to become a hegemonic project for producing space.

Urban Forest Health Monitoring in the United States

Science.gov (United States)

David J. Nowak; Daniel Twardus; Robert Hoehn; Manfred Mielke; Jeffery T. Walton; Daniel E. Crane; Anne Cumming; Jack C. Stevens

2006-01-01

To better understand the urban forest resource and its numerous values, the U.S. Department of Agriculture Forest Service has initiated a pilot program to sample the urban tree population in Indiana, Wisconsin, and New Jersey and statewide urban street tree populations in Maryland, Wisconsin, and Massachusetts. Results from the pilot study in Indiana revealed that...

Global Rural-Urban Mapping Project, Version 1 (GRUMPv1): Coastlines

Data.gov (United States)

National Aeronautics and Space Administration — The Global Rural-Urban Mapping Project, Version 1 (GRUMPv1) consists of estimates of human population for the years 1990, 1995, and 2000 by 30 arc-second (1km) grid...

Effect of vegetation on urban climate and healthy urban colonies

Energy Technology Data Exchange (ETDEWEB)

Raza, S.H.; Murthy, M.S.R.; Bhagya Lakshmi, O.; Shylaja, G. (Ecology and Environmental Biology Lab., Dept. of Botany, Osmania Univ., Hyderabad (India))

1991-01-01

The role of plants in developing a healthy atmosphere is very desirable in the context of deteriorating environment resulting from increased urbanization, industrialization and improper environmental management. This investigation has attempted to screen plants for their ability to improve the design and development of healthy environments around buildings and urban centres of Hyderabad. Ability index values were computed on the basis of canopy area, physiological characters of trees growing in polluted environments, pollution stress and population load. Azadirachta indica, Pithecolobium dulce and Cassia fistula are suggested for plantations around buildings and urban centres for minimizing pollution. Certain susceptible trees like Pongamia glabra and Polyalthia longifolia have been suggested in the diagnosis and investigation of air quality through biological means. (orig.).

Assessing atmospheric particulate matter distribution based on Saturation Isothermal Remanent Magnetization of herbaceous and tree leaves in a tropical urban environment.

Science.gov (United States)

Barima, Yao Sadaiou Sabas; Angaman, Djédoux Maxime; N'gouran, Kobenan Pierre; Koffi, N'guessan Achille; Kardel, Fatemeh; De Cannière, Charles; Samson, Roeland

2014-02-01

Particulate matter (PM) emissions, and the associated human health risks, are likely to continue increasing in urban environments of developing countries like Abidjan (Ivory Cost). This study evaluated the potential of leaves of several herbaceous and tree species as bioindicators of urban particulate matter pollution, and its variation over different land use classes, in a tropical area. Four species well distributed (presence frequencies >90%) over all land use classes, easy to harvest and whose leaves are wide enough to be easily scanned were selected, i.e.: Amaranthus spinosus (Amaranthaceae), Eleusine indica (Poaceae), Panicum maximum (Poaceae) and Ficus benjamina (Moraceae). Leaf sampling of these species was carried out at 3 distances from the road and at 3 height levels. Traffic density was also noted and finally biomagnetic parameters of these leaves were determined. Results showed that Saturation Isothermal Remanent Magnetization (SIRM) of leaves was at least 4 times higher (27.5×10(-6)A) in the vicinity of main roads and industrial areas than in parks and residential areas. The main potential sources of PM pollution were motor vehicles and industries. The slightly hairy leaves of the herbaceous plant A. spinosus and the waxy leaves of the tree F. benjamina showed the highest SIRM (25×10(-6)A). Leaf SIRM increased with distance to road (R(2)>0.40) and declined with sampling height (R(2)=0.17). The distance between 0 and 5m from the road seemed to be the most vulnerable in terms of PM pollution. This study has showed that leaf SIRM of herbaceous and tree species can be used to assess PM exposure in tropical urban environments. © 2013.

The structure, function and value of urban forests in California communities

Science.gov (United States)

E. Gregory McPherson; Qingfu Xiao; Natalie S. van Doorn; John de Goede; Jacquelyn Bjorkman; Allan Hollander; Ryan M. Boynton; James F. Quinn; James H. Thorne

2017-01-01

This study used tree data from field plots in urban areas to describe forest structure in urban areas throughout California. The plot data were used with numerical models to calculate several ecosystem services produced by trees. A series of transfer functions were calculated to scale-up results from the plots to the landscape using urban tree canopy (UTC) mapped at 1-...

Austin's Urban Forest, 2014

Science.gov (United States)

David J. Nowak; Allison R. Bodine; Robert E. Hoehn; Christopher B. Edgar; Dudley R. Hartel; Tonya W. Lister; Thomas J. Brandeis

2016-01-01

An analysis of the urban forest in Austin, Texas, reveals that this area has an estimated 33.8 million trees with tree canopy that covers 30.8 percent of the city. The most common tree species are Ashe juniper, cedar elm, live oak, sugarberry, and Texas persimmon. Trees in Austin currently store about 1.9 million tons of carbon (7.0 million tons of carbon dioxide [CO...

Urban Forests

Science.gov (United States)

David Nowak

2016-01-01

Urban forests (and trees) constitute the second forest resource considered in this report. We specifically emphasize the fact that agricultural and urban forests exist on a continuum defined by their relationship (and interrelationship) with a given landscape. These two forest types generally serve different purposes, however. Whereas agricultural forests are...

Benefits and costs of street trees in Lisbon

Science.gov (United States)

A.L. Soares; F.C. Rego; E.G. McPherson; J.R. Simpson; P.J. Peper; Q. Xiao

2011-01-01

It is well known that urban trees produce various types of benefits and costs. The computer tool i-Tree STRATUM helps quantify tree structure and function, as well as the value of some of these tree services in different municipalities. This study describes one of the first applications of STRATUM outside the U.S. Lisbon’s street trees are dominated by Celtis australis...

Project CAPTURE: using forest inventory and analysis data to prioritize tree species for conservation, management, and restoration

Science.gov (United States)

Kevin M. Potter; Barbara S. Crane; William W. Hargrove

2015-01-01

A variety of threats, most importantly climate change and insect and disease infestation, will increase the likelihood that forest tree species could experience population-level extirpation or species-level extinction during the next century. Project CAPTURE (Conservation Assessment and Prioritization of Forest Trees Under Risk of Extirpation) is a cooperative effort...

Analysis of local scale tree-atmosphere interaction on pollutant concentration in idealized street canyons and application to a real urban junction

Science.gov (United States)

Buccolieri, Riccardo; Salim, Salim Mohamed; Leo, Laura Sandra; Di Sabatino, Silvana; Chan, Andrew; Ielpo, Pierina; de Gennaro, Gianluigi; Gromke, Christof

2011-03-01

This paper first discusses the aerodynamic effects of trees on local scale flow and pollutant concentration in idealized street canyon configurations by means of laboratory experiments and Computational Fluid Dynamics (CFD). These analyses are then used as a reference modelling study for the extension a the neighbourhood scale by investigating a real urban junction of a medium size city in southern Italy. A comparison with previous investigations shows that street-level concentrations crucially depend on the wind direction and street canyon aspect ratio W/H (with W and H the width and the height of buildings, respectively) rather than on tree crown porosity and stand density. It is usually assumed in the literature that larger concentrations are associated with perpendicular approaching wind. In this study, we demonstrate that while for tree-free street canyons under inclined wind directions the larger the aspect ratio the lower the street-level concentration, in presence of trees the expected reduction of street-level concentration with aspect ratio is less pronounced. Observations made for the idealized street canyons are re-interpreted in real case scenario focusing on the neighbourhood scale in proximity of a complex urban junction formed by street canyons of similar aspect ratios as those investigated in the laboratory. The aim is to show the combined influence of building morphology and vegetation on flow and dispersion and to assess the effect of vegetation on local concentration levels. To this aim, CFD simulations for two typical winter/spring days show that trees contribute to alter the local flow and act to trap pollutants. This preliminary study indicates that failing to account for the presence of vegetation, as typically practiced in most operational dispersion models, would result in non-negligible errors in the predictions.

Managing Tree Diversity: A Comparison of Suburban Development in Two Canadian Cities

Directory of Open Access Journals (Sweden)

Sophie A. Nitoslawski

2016-05-01

Full Text Available Is (suburban forest diversity shaped by previous land use? This study was designed to quantitatively assess the impacts of subdivision development on urban tree-species composition in two Canadian cities: Halifax, Nova Scotia, and London, Ontario. The main goal was to determine whether cities with contrasting pre-urbanized or pre-settlement landscapes—woodlands in Halifax and agricultural fields in London—also revealed differences in urban tree diversity losses and/or gains due to urbanization. In each city, four residential neighbourhoods representing two age categories, older and newer (40–50 years, <15 years, were examined and trees on three land types were sampled: public (street, private (residential, and remnant (woodland. All public street trees within the chosen neighbourhoods were inventoried and approximately 10% of the residential property lots were sampled randomly. Plots were examined in remnant forests in or near each city, representing the original forest habitats prior to agricultural and/or urban landscape transformations. Diameter at breast height, species richness and evenness, and proportions of native and non-native trees were measured. In both cities, streetscapes in newer neighbourhoods exhibit greater species richness and evenness, and are characterized by substantially more native trees. Despite this trend, developers and home owners continue to intensively plant non-native species on newer and smaller property lots. Older neighbourhoods in Halifax containing remnant forest stands hold the greatest number of native trees on private property, alluding to the importance of residual forest buffers and patches in promoting naturalness in the private urban forest. These results suggest that identifying and quantifying flows of species between green spaces during and after development is valuable in order to effectively promote native species establishment and enhance overall urban forest diversity.

Multi-actor decision making using mixed reality technologies Urban projects and multi-actor collaboration

OpenAIRE

Basile,, Maria; Ozdirlik, Burcu; Terrin,, Jean-Jacques

2009-01-01

International audience; This paper is based on the results of an ongoing research project, IPCity, on the application of mixed reality technologies in urban environments. It questions the relevance of traditional language and communication medium such as drawings, perspectives and 3D models in the co-production of urban projects in multi-actor working environments. It then discusses the possible use of “mixed reality technologies” as alternative medium through five workshops organised within ...

Why count trees? Volunteer motivations and experiences with tree monitoring in New York City

Science.gov (United States)

Michelle L. Johnson; Lindsay K. Campbell; Erika S. Svendsen; Philip. Silva

2018-01-01

Volunteer programs can benefit from a deeper understanding of the motivations and experiences of people engaged in citizen science. Research to date has studied motivations of citizen scientists and tree-planting volunteers. Less work has focused on tree-monitoring volunteers, a role that is rapidly increasing as more cities involve the public in monitoring the urban...

Influence of trees on the dispersion of pollutants in an urban street canyon - experimental investigation of the flow and concentration field

NARCIS (Netherlands)

Gromke, C.B.; Ruck, B.

2007-01-01

Flow field and concentration measurements have been performed in an idealized model of an urban street canyon with one row of trees arranged along the center axis. The model was set up in an atmospheric boundary layer wind tunnel and the approach flow was directed perpendicular to the street axis. A

Houston’s Urban Forest, 2015

Science.gov (United States)

David J. Nowak; Allison R. Bodine; Robert E. Hoehn; Christopher B. Edgar; Gretchen Riley; Dudley R. Hartel; Kerry J. Dooley; Sharon M. Stanton; Mark A. Hatfield; Thomas J. Brandeis; Tonya W. Lister

2017-01-01

An analysis of the urban forest in Houston, Texas, reveals that this area has an estimated 33.3 million live trees with tree canopy that covers 18.4 percent of the city. Roughly 19.2 million of the city’s trees are located on private lands. The most common tree species are yaupon, Chinese tallowtree, Chinese privet, Japanese privet, and sugarberry. Trees in Houston...

Measuring urban tree loss dynamics across residential landscapes

Data.gov (United States)

U.S. Environmental Protection Agency — The spatial arrangement of urban vegetation depends on urban morphology and socio-economic settings. Urban vegetation changes over time because of human management....

Seasonal variation of bacterial endophytes in urban trees

Directory of Open Access Journals (Sweden)

Shu Yi eShen

2015-05-01

Full Text Available Bacterial endophytes, non-pathogenic bacteria residing within plants, contribute to the growth and development of plants and their ability to adapt to adverse conditions. In order to fully exploit the capabilities of these bacteria, it is necessary to understand the extent to which endophytic communities vary between species and over time. The endophytes of Acer negundo, Ulmus pumila and Ulmus parvifolia were sampled over three seasons and analyzed using culture dependent and independent methods (culture on two media, terminal restriction fragment length polymorphism, and tagged pyrosequencing of 16S ribosomal amplicons. The majority of culturable endophytes isolated were Actinobacteria, and all the samples harbored Bacillus, Curtobacterium, Frigoribacterium, Methylobacterium, Paenibacilllus and Sphingomonas species. Regardless of culture medium used, only the culturable communities obtained in the winter for A. negundo could be distinguished from those of Ulmus spp.. In contrast, the nonculturable communities were dominated by Proteobacteria and Actinobacteria, particularly Erwinia, Ralstonia and Sanguibacter spp.. The presence and abundance of various bacterial classes and phyla changed with the changing seasons. Multivariate analysis on the culture independent data revealed significant community differences between the endophytic communities of A. negundo and Ulmus spp., but overall season was the main determinant of endophytic community structure. This study suggests investigations of the studies ofendophytic populations of urban trees should expect to find significant seasonal and species-specific community differences and sampling should proceed accordingly.

Isoprene Emission Factors for Subtropical Street Trees for Regional Air Quality Modeling.

Science.gov (United States)

Dunn-Johnston, Kristina A; Kreuzwieser, Jürgen; Hirabayashi, Satoshi; Plant, Lyndal; Rennenberg, Heinz; Schmidt, Susanne

2016-01-01

Evaluating the environmental benefits and consequences of urban trees supports their sustainable management in cities. Models such as i-Tree Eco enable decision-making by quantifying effects associated with particular tree species. Of specific concern are emissions of biogenic volatile organic compounds, particularly isoprene, that contribute to the formation of photochemical smog and ground level ozone. Few studies have quantified these potential disservices of urban trees, and current models predominantly use emissions data from trees that differ from those in our target region of subtropical Australia. The present study aimed (i) to quantify isoprene emission rates of three tree species that together represent 16% of the inventoried street trees in the target region; (ii) to evaluate outputs of the i-Tree Eco model using species-specific versus currently used, generic isoprene emission rates; and (iii) to evaluate the findings in the context of regional air quality. Isoprene emission rates of (Myrtaceae) and (Proteaceae) were 2.61 and 2.06 µg g dry leaf weight h, respectively, whereas (Sapindaceae) was a nonisoprene emitter. We substituted the generic isoprene emission rates with these three empirical values in i-Tree Eco, resulting in a 182 kg yr (97%) reduction in isoprene emissions, totaling 6284 kg yr when extrapolated to the target region. From these results we conclude that care has to be taken when using generic isoprene emission factors for urban tree models. We recommend that emissions be quantified for commonly planted trees, allowing decision-makers to select tree species with the greatest overall benefit for the urban environment. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Web-based tree crown condition evaluation training tool for urban and community forestry

Science.gov (United States)

Neil Clark; Matthew Winn; Philip Araman

2009-01-01

Volunteers are getting involved more and more, particularly in monitoring applications within the context of urban and community forestry. Training numerous volunteers becomes a substantial task given the numbers of people, time available, and a multitude of other projects. Hundreds of different individuals may be involved in a single field season. These individuals...

Trees as bioindicator of heavy metal pollution in three European cities

Energy Technology Data Exchange (ETDEWEB)

Sawidis, T. [Department of Botany, University of Thessaloniki, 54124 Thessaloniki (Greece); Breuste, J., E-mail: juergen.breuste@sbg.ac.at [Department of Geography and Geology, University of Salzburg, 5010 Salzburg (Austria); Mitrovic, M.; Pavlovic, P. [Department of Ecology, Institute for Biological Research ' Sinisa Stankovic' , University of Belgrade, Bulevar despota Stefana 142, 11060 Belgrade (Serbia); Tsigaridas, K. [Department of Botany, University of Thessaloniki, 54124 Thessaloniki (Greece)

2011-12-15

Concentrations of four heavy metals were determined in tree leaves and bark collected from polluted and non-polluted areas of three European cities (Salzburg, Belgrade and Thessaloniki) for a comparative study. Platanus orientalis L. and Pinus nigra Arn., widespread in urban northern and southern Europe, were tested for their suitability for air quality biomonitoring. Leaves and barks were collected uniformly of an initial quantity of about 30 g of each sample. Analysis was accomplished by electrothermal atomic absorption spectrometry after total digestion. Site-dependent variations were found with the highest concentration level measured in Belgrade, followed by Thessaloniki and Salzburg. A higher accumulation of heavy metals was found in bark compared to leaves. Pine tree bark, accumulating higher concentrations of trace metals compared to plane tree bark, shows a higher efficiency as bioindicator for urban pollution. Both indicator species are suitable for comparative studies on bioindication of urban air pollution. - Highlights: > Oriental plane and Austrian pine are suitable for comparative urban air quality biomonitoring of heavy metal pollution. > Pine tree is excellently suitable as urban bioindicator as it accumulates high concentrations of trace metals. > The highest heavy metal pollution was found in Belgrade followed by Thessaloniki and Salzburg. - Oriental plane (Platanus orientalis L.) and Austrian pine (Pinus nigra Arn.), widespread in urban northern and southern Europe, are suitable for comparative biomonitoring of urban air pollution.

Trees as bioindicator of heavy metal pollution in three European cities

International Nuclear Information System (INIS)

Sawidis, T.; Breuste, J.; Mitrovic, M.; Pavlovic, P.; Tsigaridas, K.

2011-01-01

Concentrations of four heavy metals were determined in tree leaves and bark collected from polluted and non-polluted areas of three European cities (Salzburg, Belgrade and Thessaloniki) for a comparative study. Platanus orientalis L. and Pinus nigra Arn., widespread in urban northern and southern Europe, were tested for their suitability for air quality biomonitoring. Leaves and barks were collected uniformly of an initial quantity of about 30 g of each sample. Analysis was accomplished by electrothermal atomic absorption spectrometry after total digestion. Site-dependent variations were found with the highest concentration level measured in Belgrade, followed by Thessaloniki and Salzburg. A higher accumulation of heavy metals was found in bark compared to leaves. Pine tree bark, accumulating higher concentrations of trace metals compared to plane tree bark, shows a higher efficiency as bioindicator for urban pollution. Both indicator species are suitable for comparative studies on bioindication of urban air pollution. - Highlights: → Oriental plane and Austrian pine are suitable for comparative urban air quality biomonitoring of heavy metal pollution. → Pine tree is excellently suitable as urban bioindicator as it accumulates high concentrations of trace metals. → The highest heavy metal pollution was found in Belgrade followed by Thessaloniki and Salzburg. - Oriental plane (Platanus orientalis L.) and Austrian pine (Pinus nigra Arn.), widespread in urban northern and southern Europe, are suitable for comparative biomonitoring of urban air pollution.

Land-use change outweighs projected effects of changing rainfall on tree cover in sub-Saharan Africa.

Science.gov (United States)

Aleman, Julie C; Blarquez, Olivier; Staver, Carla A

2016-09-01

Global change will likely affect savanna and forest structure and distributions, with implications for diversity within both biomes. Few studies have examined the impacts of both expected precipitation and land use changes on vegetation structure in the future, despite their likely severity. Here, we modeled tree cover in sub-Saharan Africa, as a proxy for vegetation structure and land cover change, using climatic, edaphic, and anthropic data (R(2)  = 0.97). Projected tree cover for the year 2070, simulated using scenarios that include climate and land use projections, generally decreased, both in forest and savanna, although the directionality of changes varied locally. The main driver of tree cover changes was land use change; the effects of precipitation change were minor by comparison. Interestingly, carbon emissions mitigation via increasing biofuels production resulted in decreases in tree cover, more severe than scenarios with more intense precipitation change, especially within savannas. Evaluation of tree cover change against protected area extent at the WWF Ecoregion scale suggested areas of high biodiversity and ecosystem services concern. Those forests most vulnerable to large decreases in tree cover were also highly protected, potentially buffering the effects of global change. Meanwhile, savannas, especially where they immediately bordered forests (e.g. West and Central Africa), were characterized by a dearth of protected areas, making them highly vulnerable. Savanna must become an explicit policy priority in the face of climate and land use change if conservation and livelihoods are to remain viable into the next century. © 2016 John Wiley & Sons Ltd.

URBAN SPRAWL MODELING, AIR QUALITY MONITORING AND RISK COMMUNICATION: THE NORTHEAST OHIO PROJECT

Science.gov (United States)

The Northeast Ohio Urban Sprawl, Air Quality Monitoring, and Communications Project (hereafter called the Northeast Ohio Project) provides local environmental and health information useful to residents, local officials, community planners, and others in a 15 county region in the ...

The urban forests of Philadelphia

Science.gov (United States)

David J. Nowak; Allison R. Bodine; Robert Hoehn; Alexis Ellis; Sarah C. Low; Lara A. Roman; Jason G. Henning; Emily Stephan; Tom Taggert; Ted. Endreny

2016-01-01

An analysis of the urban forest in Philadelphia, Pennsylvania, reveals that this city has an estimated 2.9 million trees (encompassing all woody plants greater than 1 inch diameter at breast height [d.b.h]) with tree canopy that covers 20 percent of the city. The most common tree species are spicebush, black cherry, ash, tree-of-heaven, and boxelder, but the most...

Future Urban Climate Projection in A Tropical Megacity Based on Global and Regional Scenarios

Science.gov (United States)

Darmanto, N. S.; Varquez, A. C. G.; Kanda, M.

2017-12-01

Cities in Asian developing countries experience rapid transformation in urban morphology and energy consumption, which correspondingly affects urban climate. Weather Research and Forecasting (WRF) Model coupled with improved single-layer urban canopy model incorporating realistic distribution of urban parameters and anthropogenic heat emission (AHE) in the tropic Jakarta Greater Area was conducted. Simulation was conducted during the dry months from 2006 to 2015 and agreed well with point and satellite observation. The same technology coupled with pseudo global warming (PGW) method based on representative concentration pathways (RCP) scenario 2.6 and 8.5 was conducted to produce futuristic climate condition in 2050. Projected urban morphology and AHE in 2050s were constructed using regional urban growing model with shared socioeconomic pathways (SSP) among its inputs. Compact future urban configuration, based on SSP1, was coupled to RCP2.6. Unrestrained future urban configuration, based on SSP3, was coupled to RCP8.5. Results show that background warming from RCP 2.6 and 8.5 will increase background temperature by 0.55°C and 1.2°C throughout the region, respectively. Future projection of urban sprawl results to an additional 0.3°C and 0.5°C increase on average, with maximum increase of 1.1°C and 1.3°C due to urban effect for RCP2.6/compact and RCP8.5/unrestrained, respectively. Higher moisture content in urban area is indicated in the future due to higher evaporation. Change in urban roughness is likely affect slower wind velocity in urban area and sea breeze front inland penetration the future compare with current condition. Acknowledgement: This research was supported by the Environment Research and Technology Development Fund (S-14) of the Ministry of the Environment, Japan.

The Urban Environment Can Modify Drought Stress of Small-Leaved Lime (Tilia cordata Mill. and Black Locust (Robinia pseudoacacia L.

Directory of Open Access Journals (Sweden)

Astrid Moser

2016-03-01

Full Text Available The urban environment characterized by various stresses poses challenges to trees. In particular, water deficits and high temperatures can cause immense drought stress to urban trees, resulting in reduced growth and die-off. Drought-tolerant species are expected to be resilient to these conditions and are therefore advantageous over other, more susceptible species. However, the drought tolerance of urban trees in relation to the specific growth conditions in urban areas remains poorly researched. This study aimed to analyze the annual growth and drought tolerance of two common urban tree species, namely small-leaved lime (Tilia cordata Mill. (T. cordata and black locust (Robinia pseudoacacia L. (R. pseudoacacia, in two cities in southern Germany in relation to their urban growing conditions. Marked growth reductions during drought periods and subsequent fast recovery were found for R. pseudoacacia, whereas T. cordata exhibited continued reduced growth after a drought event, although these results were highly specific to the analyzed city. We further show that individual tree characteristics and environmental conditions significantly influence the growth of urban trees. Canopy openness and other aspects of the surrounding environment (water supply and open surface area of the tree pit, tree size, and tree species significantly affect urban tree growth and can modify the ability of trees to tolerate the drought stress in urban areas. Sustainable tree planting of well adapted tree species to their urban environment ensures healthy trees providing ecosystem services for a high quality of life in cities.

Optimal tree design for daylighting in residential buildings

Energy Technology Data Exchange (ETDEWEB)

Hongbing, Wang [College of Landscape Architecture, Beijing Forestry University, 35, East Qinghua Rd., Beijing (China); Shanghai Botanical Garden, 1111, Longwu Rd., Shanghai (China); Jun, Qin; Yonghong, Hu [Shanghai Botanical Garden, 1111, Longwu Rd., Shanghai (China); Li, Dong [College of Landscape Architecture, Beijing Forestry University, 35, East Qinghua Rd., Beijing (China)

2010-12-15

Urban reforestation is advocated as an efficient countermeasure to the intensification of urban heat islands. The greening and beautification of residential quarters is one of the main concerns of residents, while lighting and ventilation are two main energy-consuming building services. Hence, the tree layout in green space between buildings is important, and it is necessary to determine the relationships between trees and buildings. This study takes Shanghai as a case study to optimize tree design between residential buildings and meet good daylighting requirements. Models were made using software such as AutoCAD and SketchUp. The relationships between maximum tree height and building separation were determined. For the same building layout, there were different tree height limits according to crown shape; the order of decreasing height limits was cylindrical, conical, spherical, and inverted conical crowns. Three cases having different green space between building layouts were studied. Their maximum tree heights differed. Overall, our model helps us realize good daylighting of a building environment. The formula allows us to determine which trees to plant between buildings in that we can predict the effects of future tree growth on building daylighting. (author)

High-resolution tree canopy mapping for New York City using LIDAR and object-based image analysis

Science.gov (United States)

MacFaden, Sean W.; O'Neil-Dunne, Jarlath P. M.; Royar, Anna R.; Lu, Jacqueline W. T.; Rundle, Andrew G.

2012-01-01

Urban tree canopy is widely believed to have myriad environmental, social, and human-health benefits, but a lack of precise canopy estimates has hindered quantification of these benefits in many municipalities. This problem was addressed for New York City using object-based image analysis (OBIA) to develop a comprehensive land-cover map, including tree canopy to the scale of individual trees. Mapping was performed using a rule-based expert system that relied primarily on high-resolution LIDAR, specifically its capacity for evaluating the height and texture of aboveground features. Multispectral imagery was also used, but shadowing and varying temporal conditions limited its utility. Contextual analysis was a key part of classification, distinguishing trees according to their physical and spectral properties as well as their relationships to adjacent, nonvegetated features. The automated product was extensively reviewed and edited via manual interpretation, and overall per-pixel accuracy of the final map was 96%. Although manual editing had only a marginal effect on accuracy despite requiring a majority of project effort, it maximized aesthetic quality and ensured the capture of small, isolated trees. Converting high-resolution LIDAR and imagery into usable information is a nontrivial exercise, requiring significant processing time and labor, but an expert system-based combination of OBIA and manual review was an effective method for fine-scale canopy mapping in a complex urban environment.

Differences in the impacts of formal and informal recreational trails on urban forest loss and tree structure.

Science.gov (United States)

Ballantyne, Mark; Pickering, Catherine Marina

2015-08-15

Recreational trails are one of the most common types of infrastructure used for nature-based activities such as hiking and mountain biking worldwide. Depending on their design, location, construction, maintenance and use, these trails differ in their environmental impacts. There are few studies, however, comparing the impacts of different trail types including between formal management-created trails and informal visitor-created trails. Although both types of trails can be found in remote natural areas, dense networks of them often occur in forests close to cities where they experience intense visitor use. To assess the relative impacts of different recreational trails in urban forests, we compared the condition of the trail surface, loss of forest strata and changes in tree structure caused by seven types of trails (total network 46.1 km) traversing 17 remnants of an endangered urban forest in Australia. After mapping and classifying all trails, we assessed their impact on the forest condition at 125 sites (15 sites per trail type, plus 15 control sites within undisturbed forest). On the trail sites, the condition of the trail surface, distance from the trail edge to four forest strata (litter, understory, midstorey and tree cover) and structure of the tree-line were assessed. Informal trails generally had poorer surface conditions and were poorly-designed and located. Per site, formal and informal trails resulted in similar loss of forest strata, with wider trails resulting in greater loss of forest. Because there were more informal trails, however, they accounted for the greatest cumulative forest loss. Structural impacts varied, with the widest informal trails and all formal hardened trails resulting in similar reductions in canopy cover and tree density but an increase in saplings. These structural impacts are likely a function of the unregulated and intense use of large informal trails, and disturbance from the construction and maintenance of formal trails

Detailed Urban Heat Island Projections for Cities Worldwide: Dynamical Downscaling CMIP5 Global Climate Models

Directory of Open Access Journals (Sweden)

Dirk Lauwaet

2015-06-01

Full Text Available A new dynamical downscaling methodology to analyze the impact of global climate change on the local climate of cities worldwide is presented. The urban boundary layer climate model UrbClim is coupled to 11 global climate models contained in the Coupled Model Intercomparison Project 5 archive, conducting 20-year simulations for present (1986–2005 and future (2081–2100 climate conditions, considering the Representative Concentration Pathway 8.5 climate scenario. The evolution of the urban heat island of eight different cities, located on three continents, is quantified and assessed, with an unprecedented horizontal resolution of a few hundred meters. For all cities, urban and rural air temperatures are found to increase strongly, up to 7 °C. However, the urban heat island intensity in most cases increases only slightly, often even below the range of uncertainty. A potential explanation, focusing on the role of increased incoming longwave radiation, is put forth. Finally, an alternative method for generating urban climate projections is proposed, combining the ensemble temperature change statistics and the results of the present-day urban climate.

Removal of Ozone by Urban and Peri-Urban Forests: Evidence from Laboratory, Field, and Modeling Approaches

Science.gov (United States)

Carlo Calfapietra; Arianna Morani; Gregorio Sgrigna; Sara Di Giovanni; Valerio Muzzini; Emanuele Pallozzi; Gabriele Guidolotti; David Nowak; Silvano Fares

2016-01-01

A crucial issue in urban environments is the interaction between urban trees and atmospheric pollution, particularly ozone (O3). Ozone represents one of the most harmful pollutants in urban and peri-urban environments, especially in warm climates. Besides the large interest in reducing anthropogenic and biogenic precursors of O3...

Monitoring Urban Tree Cover Using Object-Based Image Analysis and Public Domain Remotely Sensed Data

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Meghan Halabisky

2011-10-01

Full Text Available Urban forest ecosystems provide a range of social and ecological services, but due to the heterogeneity of these canopies their spatial extent is difficult to quantify and monitor. Traditional per-pixel classification methods have been used to map urban canopies, however, such techniques are not generally appropriate for assessing these highly variable landscapes. Landsat imagery has historically been used for per-pixel driven land use/land cover (LULC classifications, but the spatial resolution limits our ability to map small urban features. In such cases, hyperspatial resolution imagery such as aerial or satellite imagery with a resolution of 1 meter or below is preferred. Object-based image analysis (OBIA allows for use of additional variables such as texture, shape, context, and other cognitive information provided by the image analyst to segment and classify image features, and thus, improve classifications. As part of this research we created LULC classifications for a pilot study area in Seattle, WA, USA, using OBIA techniques and freely available public aerial photography. We analyzed the differences in accuracies which can be achieved with OBIA using multispectral and true-color imagery. We also compared our results to a satellite based OBIA LULC and discussed the implications of per-pixel driven vs. OBIA-driven field sampling campaigns. We demonstrated that the OBIA approach can generate good and repeatable LULC classifications suitable for tree cover assessment in urban areas. Another important finding is that spectral content appeared to be more important than spatial detail of hyperspatial data when it comes to an OBIA-driven LULC.

New urban and regional management instruments: Santo André and the Tamanduateí axis project case

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Margarida Nobue Sakata

2009-06-01

Full Text Available From the end of twenty century, the crisis that came with to the end of the intensive capitalism system have been motivated much political and economical transformation at global scale. The post war breakdown reconstruction, oil crisis, the advances in informatics and telecommunication caused changes in the regional structure of many countries in the world. The movement of manufacturing activities of the old industrial metropolis occasioned the decadence and ascension of different urban regions. As an answer to these transformations, the paradigm of urban politics of many cities has been changed with the dismantling of the traditional planning system and accepting new management and urban intervention forms, as strategic planning, big urban projects, urban legislation flexibility, city marketing, etc. Recently many authors have done a critical review of this new urban management. This present work analyses the transformations suffered by Santo André, municipality of São Paulo metropolitan region and the implementation of Tamanduateí Axis Project, analyzing them in this context and these new urban management forms, evaluating its impacts and results.

Surface moisture estimation in urban areas

Science.gov (United States)

Jiang, Yitong

Surface moisture is an important parameter because it modifies urban microclimate and surface layer meteorology. The primary objectives of this paper are: 1) to analyze the impact of surface roughness from buildings on surface moisture in urban areas; and 2) to quantify the impact of surface roughness resulting from urban trees on surface moisture. To achieve the objectives, two hypotheses were tested: 1) the distribution of surface moisture is associated with the structural complexity of buildings in urban areas; and 2) The distribution and change of surface moisture is associated with the distribution and vigor of urban trees. The study area is Indianapolis, Indiana, USA. In the part of the morphology of urban trees, Warren Township was selected due to the limitation of tree inventory data. To test the hypotheses, the research design was made to extract the aerodynamic parameters, such as frontal areas, roughness length and displacement height of buildings and trees from Terrestrial and Airborne LiDAR data, then to input the aerodynamic parameters into the urban surface energy balance model. The methodology was developed for comparing the impact of aerodynamic parameters from LiDAR data with the parameters that were derived empirically from land use and land cover data. The analytical procedures are discussed below: 1) to capture the spatial and temporal variation of surface moisture, daily and hourly Land Surface Temperature (LST) were downscaled from 4 km to 1 km, and 960 m to 30 m, respectively, by regression between LST and various components that impact LST; 2) to estimate surface moisture, namely soil moisture and evapotranspiration (ET), land surfaces were classified into soil, vegetation, and impervious surfaces, using Linear Spectral Mixture Analysis (LSMA); 3) aerodynamic parameters of buildings and trees were extracted from Airborne and Terrestrial LiDAR data; 4) the Temperature-Vegetation-Index (TVX) method, and the Two-Source-Energy-Balance (TSEB

L’Aquila Smart Clean Air City: The Italian Pilot Project for Healthy Urban Air

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Alessandro Avveduto

2017-11-01

Full Text Available Exposure to atmospheric pollution is a major concern for urban populations. Currently, no effective strategy has been adopted to tackle the problem. The paper presents the Smart Clean Air City project, a pilot experiment concerning the improvement in urban air quality. Small wet scrubber systems will be operating in a network configuration in suitable urban areas of L’Aquila city (Italy. The purpose of this work is to describe the project and show the preliminary results obtained in the characterization of two urban sites before the remediation test; the main operating principles of the wet scrubber system will be discussed, as well as the design of the mobile treatment plant for the processing of wastewater resulting from scrubber operation. Measurements of particle size distributions in the range of 0.30–25 µm took place in the two sites of interest, an urban background and a traffic area in the city of L’Aquila. The mean number concentration detected was 2.4 × 107 and 4.5 × 107 particles/m3, respectively. Finally, theoretical assessments, performed by Computational Fluid Dynamics (CFD codes, will show the effects of the wet scrubber operation on air pollutants under different environmental conditions and in several urban usage patterns.

Air pollution prevention through urban heat island mitigation: An update on the urban heat island pilot project

Energy Technology Data Exchange (ETDEWEB)

Gorsevski, V.; Taha, H.; Quattrochi, D.; Luvall, J.

1998-07-01

Urban heat islands increase the demand for cooling energy and accelerate the formation of smog. They are created when natural vegetation is replaced by heat-absorbing surfaces such as building roofs and walls, parking lots, and streets. Through the implementation of measures designed to mitigate the urban heat island, communities can decrease their demand for energy and effectively cool the metropolitan landscape. In addition to the economic benefits, using less energy leads to reductions in emission of CO{sub 2}--a greenhouse gas--as well as ozone (smog) precursors such as NOx and VOCs. Because ozone is created when NOx and VOCs photochemically combine with heat and solar radiation, actions taken to lower ambient air temperature can significantly reduce ozone concentrations in certain areas. Measures to reverse the urban heat island include afforestation and the widespread use of highly reflective surfaces. To demonstrate the potential benefits of implementing these measures, EPA has teamed up with NASA and LBNL to initiate a pilot project with three US cities. As part of the pilot, NASA will use remotely-sensed data to quantify surface temperature, albedo, the thermal response number and NDVI vegetation of each city. This information will be used by scientists at Lawrence Berkeley National Laboratory (LBNL) along with other data as inputs to model various scenarios that will help quantify the potential benefits of urban heat island mitigation measures in terms of reduced energy use and pollution. This paper will briefly describe this pilot project and provide an update on the progress to date.

The tree-species-specific effect of forest bathing on perceived anxiety alleviation of young-adults in urban forests

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Haoming Guan

2017-12-01

Full Text Available Forest bathing, i.e. spending time in a forest to walk, view and breathe in a forest, can alleviate the mental depression of visitors, but the tree-species-specific effect of this function by the urban forest is unknown. In this study, sixty-nine university students (aged 19-22, male ratio: 38% were recruited as participants to visit urban forests dominated by birch (Betula platyphylla Suk., maple (Acer triflorum Komarov and oak (Quercus mongolica Fisch. ex Ledeb trees in a park at the center of Changchun City, Northeast China. In the maple forest only the anxiety from study interest was decreased, while the anxiety from employment pressure was alleviated to the most extent in the birch forest. Participants perceived more anxiety from lesson declined in the oak forest than in the birch forest. Body parameters of weight and age were correlated with the anti-anxiety scores. In the oak forest, female participants can perceive more anxiety alleviation than male participants. For university students, forest bathing in our study can promote their study interest. Forest bathing can be more effective to alleviate the anxiety of young adults with greater weight. The birch forest was recommended to be visited by students to alleviate the pressure of employment worry, and the oak forest was recommended to be visited by girls.

Assessing urban forest effects and values of the Great Plains: Kansas, Nebraska, North Dakota, South Dakota

Science.gov (United States)

David J. Nowak; Robert E. III Hoehn; Daniel E. Crane; Allison R. Bodine

2012-01-01

This report details the evaluation of the urban tree resources of the north-central Great Plains region of the United States. Specifically this report provides a more comprehensive understanding of the species composition and structural and functional benefits of the urban forests in the states of Kansas (33.1 million urban trees), Nebraska (13.3 million urban trees),...

Market-based approaches to tree valuation

Science.gov (United States)

Geoffrey H. Donovan; David T. Butry

2008-01-01

A recent four-part series in Arborist News outlined different appraisal processes used to value urban trees. The final article in the series described the three generally accepted approaches to tree valuation: the sales comparison approach, the cost approach, and the income capitalization approach. The author, D. Logan Nelson, noted that the sales comparison approach...

Urban warming trumps natural enemy regulation of herbivorous pests.

Science.gov (United States)

Dale, Adam G; Frank, Steven D

Trees provide ecosystem services that counter negative effects of urban habitats on human and environmental health. Unfortunately, herbivorous arthropod pests are often more abundant on urban than rural trees, reducing tree growth, survival, and ecosystem services. Previous research where vegetation complexity was reduced has attributed elevated urban pest abundance to decreased regulation by natural enemies. However, reducing vegetation complexity, particularly the density of overstory trees, also makes cities hotter than natural habitats. We ask how urban habitat characteristics influence an abiotic factor, temperature, and a biotic factor, natural enemy abundance, in regulating the abundance of an urban forest pest, the gloomy scale, (Melanaspis tenebricosa). We used a map of surface temperature to select red maple trees (Acer rubrum) at warmer and cooler sites in Raleigh, North Carolina, USA. We quantified habitat complexity by measuring impervious surface cover, local vegetation structural complexity, and landscape scale vegetation cover around each tree. Using path analysis, we determined that impervious surface (the most important habitat variable) increased scale insect abundance by increasing tree canopy temperature, rather than by reducing natural enemy abundance or percent parasitism. As a mechanism for this response, we found that increasing temperature significantly increases scale insect fecundity and contributes to greater population increase. Specifically, adult female M. tenebricosa egg sets increased by approximately 14 eggs for every 1°C increase in temperature. Climate change models predict that the global climate will increase by 2–3°C in the next 50–100 years, which we found would increase scale insect abundance by three orders of magnitude. This result supports predictions that urban and natural forests will face greater herbivory in the future, and suggests that a primary cause could be direct, positive effects of warming on herbivore

Structure of a forested urban park: implications for strategic management.

Science.gov (United States)

Millward, Andrew A; Sabir, Senna

2010-11-01

Informed management of urban parks can provide optimal conditions for tree establishment and growth and thus maximize the ecological and aesthetic benefits that trees provide. This study assesses the structure, and its implications for function, of the urban forest in Allan Gardens, a 6.1 ha downtown park in the City of Toronto, Canada, using the Street Tree Resource Analysis Tool for Urban Forest Managers (STRATUM). Our goal is to present a framework for collection and analysis of baseline data that can inform a management strategy that would serve to protect and enhance this significant natural asset. We found that Allan Garden's tree population, while species rich (43), is dominated by maple (Acer spp.) (48% of all park trees), making it reliant on very few species for the majority of its ecological and aesthetic benefits and raising disease and pest-related concerns. Age profiles (using size as a proxy) showed a dominance of older trees with an inadequate number of individuals in the young to early middle age cohort necessary for short- to medium-term replacement. Because leaf area represents the single-most important contributor to urban tree benefits modelling, we calculated it separately for every park tree, using hemispheric photography, to document current canopy condition. These empirical measurements were lower than estimates produced by STRATUM, especially when trees were in decline and lacked full canopies, highlighting the importance of individual tree condition in determining leaf area and hence overall forest benefits. Stewardship of natural spaces within cities demands access to accurate and timely resource-specific data. Our work provides an uncomplicated approach to the acquisition and interpretation of these data in the context of a forested urban park. Copyright 2010 Elsevier Ltd. All rights reserved.

Impacts and adaptation for climate change in urban forests

Energy Technology Data Exchange (ETDEWEB)

Johnston, M. [Saskatchewan Research Council, Saskatoon, SK (Canada)

2006-07-01

Changes to urban trees as a result of climate change were reviewed in order to aid urban forest managers in the development of adaptive climate change strategies. Various climate change models have predicted that winter and spring temperatures will increase. Higher amounts of precipitation are also anticipated. Higher temperatures will results in evapotranspiration, which will cause soil moisture levels to decline. Climatologists have also suggested that very hot days, winter storms and high rainfall events will increase in frequency. In addition, higher levels of atmospheric carbon dioxide (CO{sub 2}) will affect photosynthesis, with associated impacts on urban tree growth. Higher temperatures and longer growing seasons will allow insect populations to build up to higher levels, and warmer and dryer summers are likely to bring longer fire seasons and more severe fires. Urban trees under stress from drought and higher temperatures will be increasingly vulnerable to existing urban stressors such as air pollution and soil compaction. However, the ecological services provided by trees will become more valuable under future climate change regimes, particularly for shading and space cooling, as well as soil aeration and stabilization and the uptake of storm water. It was suggested that future tree growth may be enhanced on sites with adequate water and nutrients, but will probably decline in areas that are already marginal. It was recommended that urban forest managers assess the present vulnerability of trees to climate-related events in order to prepare for future change. Managers should also assess their capacity to implement various strategies through municipal and provincial partnerships. It was observed that decisions taken now about forest management will play out over several decades. It was concluded that maintaining a flexible and resilient urban forest management system is the best defence, as specific climate change impacts cannot be predicted. 18 refs., 4

'Solurban' project - Solar utilisation potential of urban sites

Energy Technology Data Exchange (ETDEWEB)

Robinson, D.; Scartezzini, J.-L.; Montavon, M. [Swiss Federal Institute of Technology (EPFL), Laboratoire d' Energie Solaire et de Physique du Batiment (LESO-PB), Lausanne (Switzerland); Compagnon, R. [Ecole d' ingenieurs et d' architectes de Fribourg (EIAF), University of Applied Sciences of Western Switzerland (HES-SO), Fribourg (Switzerland)

2005-07-01

This report for the Swiss Federal Office of Energy (SFOE) presents the results of a project that examined three urban locations in Switzerland with respect to their potentials for using solar energy and daylight to reduce energy demands in the lighting, heating and hot-water generation areas. The three urban areas examined included the Matthaeus district in Basle with its older residential apartment buildings, the Bellevaux residential district of Lausanne and the Meyrin district in Geneva - a nineteen-sixties satellite town. The calculation methodology and the three-dimensional digital models used are discussed. The results, including radiation availability and sky-access are discussed. Appropriate active and passive solar technologies are reviewed.

Connectivity-oriented urban projects

NARCIS (Netherlands)

Philibert Petit, E.

2006-01-01

This thesis is about connections in the built environment, networked connections for the mobility of people at the smallest scale of the urban realm: the pedestrian scale. It deals with applications of the new science of networks as a tool for observation and assessment of connectivity in the urban

The Urban Forest Effects (UFORE) model: quantifying urban forest structure and functions

Science.gov (United States)

David J. Nowak; Daniel E. Crane

2000-01-01

The Urban Forest Effects (UFORE) computer model was developed to help managers and researchers quantify urban forest structure and functions. The model quantifies species composition and diversity, diameter distribution, tree density and health, leaf area, leaf biomass, and other structural characteristics; hourly volatile organic compound emissions (emissions that...

Private Sector-led Urban Development Projects. Management, Partnerships and Effects in the Netherlands and the UK

Directory of Open Access Journals (Sweden)

Erwin Heurkens

2012-09-01

Full Text Available Central to this research lays the concept of private sector-led urban development projects (Heurkens, 2010. Such projects involve project developers taking a leading role and local authorities adopting a facilitating role, in managing the development of an urban area, based on a clear public-private role division. Such a development strategy is quite common in Anglo-Saxon urban development practices, but is less known in Continental European practices. Nonetheless, since the beginning of the millennium such a development strategy also occurred in the Netherlands in the form of ‘concessions’. However, remarkably little empirical knowledge is available about how public and private actors collaborate on and manage private sector-led urban development projects. Moreover, it remains unclear what the effects of such projects are. This dissertation provides an understanding of the various characteristics of private sector-led urban development projects by conducting empirical case study research in the institutional contexts of the Netherlands and the UK. The research provides an answer to the following research question: What can we learn from private sector-led urban development projects in the Netherlands and UK in terms of the collaborative and managerial roles of public and private actors, and the effects of their (interactions? Indications for a market-oriented Dutch urban development practice Urban development practice in the Netherlands has been subject to changes pointing towards more private sector involvement in the built environment in the past decades. Although the current economic recession might indicate otherwise, there are several motives that indicate a continuation of private sector involvement and a private leadership role in Dutch urban development projects in the future. First, a shift towards more market-oriented development practice is the result of an evolutionary process of increased ‘neoliberalization’ and the

A Method to Quantify Plant Availability and Initiating Event Frequency Using a Large Event Tree, Small Fault Tree Model

International Nuclear Information System (INIS)

Kee, Ernest J.; Sun, Alice; Rodgers, Shawn; Popova, ElmiraV; Nelson, Paul; Moiseytseva, Vera; Wang, Eric

2006-01-01

South Texas Project uses a large fault tree to produce scenarios (minimal cut sets) used in quantification of plant availability and event frequency predictions. On the other hand, the South Texas Project probabilistic risk assessment model uses a large event tree, small fault tree for quantifying core damage and radioactive release frequency predictions. The South Texas Project is converting its availability and event frequency model to use a large event tree, small fault in an effort to streamline application support and to provide additional detail in results. The availability and event frequency model as well as the applications it supports (maintenance and operational risk management, system engineering health assessment, preventive maintenance optimization, and RIAM) are briefly described. A methodology to perform availability modeling in a large event tree, small fault tree framework is described in detail. How the methodology can be used to support South Texas Project maintenance and operations risk management is described in detail. Differences with other fault tree methods and other recently proposed methods are discussed in detail. While the methods described are novel to the South Texas Project Risk Management program and to large event tree, small fault tree models, concepts in the area of application support and availability modeling have wider applicability to the industry. (authors)

Fault tree analysis of Project S-4404, Upgrade Canyon Exhaust System

International Nuclear Information System (INIS)

Browne, E.V.; Low, J.M.; Lux, C.R.

1992-01-01

Project S-4404, Upgrade Canyon Exhaust Systems, is a $177 million project with the purpose of upgrading the Exhaust Systems for both F and H Canyon Facilities. This upgrade will replace major portions of the F and H-Canyon exhaust systems, downstream of their respective sand filters with higher capacity and more reliable systems. Because of the high cost, DOE requested Program Control ampersand Integration (PC ampersand I) to examine specific deletions to the project. PC ampersand I requested Nuclear Processes Safety Research (NPSR) to perform an analysis to compare failure rates for the existing F ampersand H Canyon exhaust systems with the proposed exhaust system and specific proposed exhaust system alternatives. The objective of this work was to perform an analysis and compare failure rates for the existing F ampersand H Canyon exhaust systems with the proposed project exhaust system and proposed project alternatives. Based on fault tree analysis, two conclusions are made. First, D ampersand D activities can be eliminated from the project with no significant decrease to exhaust system safety. Deletion of D ampersand D activities would result in a cost savings of $29 million. Second, deletion of DOE Order 6430.1A requirements regarding DBAs would decrease exhaust system safety by a factor of 12

The EVNATURB project: toward an operational platform to assess Blue Green Solutions eco-systemic services in urban environment

Science.gov (United States)

Schertzer, D. J. M.; Versini, P. A.; Tchiguirinskaia, I.

2017-12-01

Urban areas are facing an expected increase in intensity and frequency of extreme weather events due to climate change. Combined with unsustainable urbanization, this should exacerbate the environmental consequences related to the water cycle as stormwater management issues, urban heat island increase and biodiversity degradation. Blue Green Solutions (BGS), such as green roofs, vegetated swales or urban ponds, appear to be particularly efficient to reduce the potential impact of new and existing urban developments with respect to these issues. Based on this statement, the French ANR EVNATURB project aims to develop a platform to assess the eco-systemic services provided by BGS and related with the previously mentioned issues. By proposing a multi-disciplinary consortium coupling monitoring, modelling and prospecting, it attempts to tackle several scientific issues currently limiting BGS wide implementation. Based on high resolution monitored sites and modelling tools, space-time variability of the related physical processes will be studied over a wide range of scales (from the material to the district scale), as well as local social-environmental stakes and constraints, to better consider the complexity of the urban environment. The EVNATURB platform developed during the project is intended for every stakeholder involved in urban development projects (planners, architects, engineering and environmental certification companies…) and will help them to implement BGS and evaluate which ones are the most appropriate for a particular project depending on its environmental objectives and constraints, and particularly for obtaining environmental certification.

ART PUBLIC PARTICIPATION AND URBAN REGENERATION. Mapping LA MINA PROJECT

Directory of Open Access Journals (Sweden)

Núria Ricart

2009-04-01

Full Text Available The evolution of public art throughout the twentieth century has resulted since the 60’s in a kind of practical intervention in the urban domain with a strong social and participatory intention. This paper presents several of these projects in relation to the kind of participattory levels, and detecting different trends. The paper Specially focuses on the project “Cartografies de La Mina”, developed in Sant Adrià de Besòs (Barcelona between 2002 and 2005 by the POLIS Research Centre at the University of Barcelona.

PROJECT CI-NERGY: TOWARDS AN INTEGRATED ENERGY URBAN PLANNING SYSTEM FROM A DATA MODELLING AND SYSTEM ARCHITECTURE PERSPECTIVE

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G. Agugiaro

2017-09-01

Full Text Available Growing urbanisation, its related environmental impacts, and social inequalities in cities are challenges requiring a holistic urban planning perspective that takes into account the different aspects of sustainable development. One crucial point is to reconcile urban planning with environmental targets, which include decreasing energy demand and CO2 emissions, and increasing the share of renewable energy. Within this context, the project CI-NERGY aims to develop urban energy modelling, simulation and optimisation methods and tools to support decision making in urban planning. However, there are several barriers to the implementation of such tools, such as: fragmentation of involved disciplines, different stakeholders, multiplicity of scales in a city and extreme heterogeneity of data regarding all the processes to be addressed. Project CI-NERGY aims, among other goals, at overcoming these barriers, and focuses on two case study cities, Geneva in Switzerland and Vienna in Austria. In particular, project CI-NERGY faces several challenges starting with different cities, heterogeneous data sources and simulation tools, diverse user groups and their individual needs. This paper describes the experiences gathered during the project. After giving a brief overview of the project, the two case study cities, Geneva and Vienna, are briefly presented, and the focus shifts then on overall system architecture of the project, ranging from urban data modelling topics to the implementation of a Service-Oriented Architecture. Some of the challenges faced, the solutions found, as well some plans for future improvements are described and commented.

Comprehensive evaluation of environmental and economic benefits of China's urban underground transportation construction projects.

Science.gov (United States)

Yang, Xiaobin; Chen, Zhilong; Guo, Dongjun

2015-07-01

Urban underground transportation projects are introduced to address problems of scarce green land and traffic pollution. As construction of urban underground transportation is still in its infancy, there is no definite quantitative measurement on whether the construction is beneficial and what influences it will place on the region in China. This study intends to construct a comprehensive evaluation method for evaluating social, economic and environmental benefits of urban underground transportation projects and proposes the concept, role and principle for evaluation of environmental and economic benefits. It figures out relationship between the environment and factors of city development. It also summarizes three relevant factors, including transportation, biophysics and social economy, and works out indicators to evaluate the influence of urban underground transportation construction. Based on Contingent Valuation Method (CVM), Cost of Illness Approach (CIA), Human Capital Approach (HCA), this paper constructs 13 monetization calculation models for social, economic and environmental benefits in response to seven aspects, namely, reducing noise pollution and air pollution, using land efficiently, improving traffic safety, reducing traffic congestion, saving shipping time and minimizing transportation costs.

Public participation and satisfaction in urban regeneration projects in Tanzania: The case of Kariakoo, Dar es Salaam

Directory of Open Access Journals (Sweden)

Joseph Paulo Layson

2015-01-01

Full Text Available Based on predictions, almost 60% of the world population will be living in cities by 2030. Tanzania is urbanizing at a rapid rate of 4.7%, and 30% of the total population lives in urban areas. Urban regeneration projects in developing countries are facing various challenges. Moreover, the issue of challenges of community participation and satisfaction in regeneration projects is less documented. In recent decades, a bottom-up planning approach has been advocated as an approach for sustainable development planning whereby local actors participate in decision-making. But how top-down planning meets bottom-up planning is less documented, as well as the correlation between participation and satisfaction. This is due to the fact that zoning system has been dominating in urban planning, where experts zone areas according to land uses with an input from the community. In this research community participation, public satisfaction in urban regeneration projects was investigated. The research was based on Kariakoo, Dar es Salaam, Tanzania. The research explored public perceptions on satisfaction and the relationship between community participation and community satisfaction in urban regeneration projects. 292 respondents were interviewed on their perceptions on the redevelopment satisfaction. The results were analyzed using SPSS and tabulated in a form of tables, figures, and charts. The results revealed that it is not necessary that the more the participation the more the satisfaction, hence the more the quality of the service/plan. This means that several factors have an influence on satisfaction of urban redevelopment such as gender, level of education, age, time lived or stayed in the area, as well as the level of participation.

Characterization of particulate matter deposited on urban tree foliage: A landscape analysis approach

Science.gov (United States)

Lin, Lin; Yan, Jingli; Ma, Keming; Zhou, Weiqi; Chen, Guojian; Tang, Rongli; Zhang, Yuxin

2017-12-01

Plants can mitigate ambient particulate matter by cleaning the air, which is crucial to urban environments. A novel approach was presented to quantitatively characterize particulate matter deposited on urban tree foliage. This approach could accurately quantify the number, size, shape, and spatial distribution of particles with different diameters on leaves. Spatial distribution is represented by proximity, which measures the closeness of particles. We sampled three common broadleaf species and obtained images through field emission scanning electron microscopy. We conducted the object-based method to extract particles from images. We then used Fragstats to analyze the landscape characteristics of these particles in term of selected metrics. Results reveal that Salix matsudana is more efficient than Ailanthus altissima and Fraxinus chinensis in terms of the number and area of particles per unit area and the proportion of fine particulate matter. The shape complexity of the particles increases with their size. Among the three species, S. matsudana and A. altissima particles respectively yield the highest and lowest proximity. PM1 in A. altissima and PM10 in F. chinensis and S. matsudana show the highest proximity, which may influence subsequent particle retention. S. matsudana should be generally considered to collect additional small particles. Different species and particle sizes exhibit various proximities, which should be further examined to elucidate the underlying mechanism.

Modeled PM2.5 removal by trees in ten U.S. cities and associated health effects

International Nuclear Information System (INIS)

Nowak, David J.; Hirabayashi, Satoshi; Bodine, Allison; Hoehn, Robert

2013-01-01

Urban particulate air pollution is a serious health issue. Trees within cities can remove fine particles from the atmosphere and consequently improve air quality and human health. Tree effects on PM 2.5 concentrations and human health are modeled for 10 U.S. cities. The total amount of PM 2.5 removed annually by trees varied from 4.7 tonnes in Syracuse to 64.5 tonnes in Atlanta, with annual values varying from $1.1 million in Syracuse to $60.1 million in New York City. Most of these values were from the effects of reducing human mortality. Mortality reductions were typically around 1 person yr −1 per city, but were as high as 7.6 people yr −1 in New York City. Average annual percent air quality improvement ranged between 0.05% in San Francisco and 0.24% in Atlanta. Understanding the impact of urban trees on air quality can lead to improved urban forest management strategies to sustain human health in cities. -- Highlights: •Paper provides the first broad-scale estimates of city-wide tree impacts on PM 2.5 . •Trees improve overall air quality by intercepting particulate matter. •Particle resuspension can lead to short-term increases in pollutant concentrations. •Urban trees produce substantial health improvements and values. -- Air pollution modeling reveals broad-scale impacts of pollution removal by urban trees on PM 2.5 concentrations and human health

Modeling the effects of urban vegetation on air pollution

Science.gov (United States)

David J. Nowak; Patrick J. McHale; Myriam Ibarra; Daniel Crane; Jack C. Stevens; Chris J. Luley

1998-01-01

Urban vegetation can directly and indirectly affect local and regional air quality by altering the urban atmospheric environment. Trees affect local air temperature by transpiring water through their leaves, by blocking solar radiation (tree shade), which reduces radiation absorption and heat storage by various anthropogenic surfaces (e.g., buildings, roads), and by...

Tools for valuing tree and park services

Science.gov (United States)

E.G. McPherson

2010-01-01

Arborists and urban foresters plan, design, construct, and manage trees and parks in cities throughout the world. These civic improvements create walkable, cool environments, save energy, reduce stormwater runoff, sequester carbon dioxide, and absorb air pollutants. The presence of trees and green spaces in cities is associated with increases in property values,...

Growing Canopy on a College Campus: Understanding Urban Forest Change through Archival Records and Aerial Photography.

Science.gov (United States)

Roman, Lara A; Fristensky, Jason P; Eisenman, Theodore S; Greenfield, Eric J; Lundgren, Robert E; Cerwinka, Chloe E; Hewitt, David A; Welsh, Caitlin C

2017-12-01

Many municipalities are setting ambitious tree canopy cover goals to increase the extent of their urban forests. A historical perspective on urban forest development can help cities strategize how to establish and achieve appropriate tree cover targets. To understand how long-term urban forest change occurs, we examined the history of trees on an urban college campus: the University of Pennsylvania in Philadelphia, PA. Using a mixed methods approach, including qualitative assessments of archival records (1870-2017), complemented by quantitative analysis of tree cover from aerial imagery (1970-2012), our analysis revealed drastic canopy cover increase in the late 20th and early 21st centuries along with the principle mechanisms of that change. We organized the historical narrative into periods reflecting campus planting actions and management approaches; these periods are also connected to broader urban greening and city planning movements, such as City Beautiful and urban sustainability. University faculty in botany, landscape architecture, and urban design contributed to the design of campus green spaces, developed comprehensive landscape plans, and advocated for campus trees. A 1977 Landscape Development Plan was particularly influential, setting forth design principles and planting recommendations that enabled the dramatic canopy cover gains we observed, and continue to guide landscape management today. Our results indicate that increasing urban tree cover requires generational time scales and systematic management coupled with a clear urban design vision and long-term commitments. With the campus as a microcosm of broader trends in urban forest development, we conclude with a discussion of implications for municipal tree cover planning.

Growing Canopy on a College Campus: Understanding Urban Forest Change through Archival Records and Aerial Photography

Science.gov (United States)

Roman, Lara A.; Fristensky, Jason P.; Eisenman, Theodore S.; Greenfield, Eric J.; Lundgren, Robert E.; Cerwinka, Chloe E.; Hewitt, David A.; Welsh, Caitlin C.

2017-12-01

Many municipalities are setting ambitious tree canopy cover goals to increase the extent of their urban forests. A historical perspective on urban forest development can help cities strategize how to establish and achieve appropriate tree cover targets. To understand how long-term urban forest change occurs, we examined the history of trees on an urban college campus: the University of Pennsylvania in Philadelphia, PA. Using a mixed methods approach, including qualitative assessments of archival records (1870-2017), complemented by quantitative analysis of tree cover from aerial imagery (1970-2012), our analysis revealed drastic canopy cover increase in the late 20th and early 21st centuries along with the principle mechanisms of that change. We organized the historical narrative into periods reflecting campus planting actions and management approaches; these periods are also connected to broader urban greening and city planning movements, such as City Beautiful and urban sustainability. University faculty in botany, landscape architecture, and urban design contributed to the design of campus green spaces, developed comprehensive landscape plans, and advocated for campus trees. A 1977 Landscape Development Plan was particularly influential, setting forth design principles and planting recommendations that enabled the dramatic canopy cover gains we observed, and continue to guide landscape management today. Our results indicate that increasing urban tree cover requires generational time scales and systematic management coupled with a clear urban design vision and long-term commitments. With the campus as a microcosm of broader trends in urban forest development, we conclude with a discussion of implications for municipal tree cover planning.

Inventorying trees in agricultural landscapes: towards an accounting of working trees

Science.gov (United States)

C. H. Perry; C. W. Woodall; M.M. Schoeneberger

2005-01-01

Agroforestry plantings and other trees intentionally established in rural and urban areas are emerging as innovative management options for addressing resource issues and achieving landscape-level goals. An understanding of the contributions from these and future plantings would provide critical information to policy and program developers, and a comprehensive...

Conservation and restoration of forest trees impacted by non-native pathogens: the role of genetics and tree improvement

Science.gov (United States)

R.A. Sniezko; L.A. Winn

2017-01-01

North American native tree species in forest ecosystems, as well as managed forests and urban plantings, are being severely impacted by pathogens and insects. The impacts of these pathogens and insects often increase over time, and they are particularly acute for those species affected by non-native pathogens and insects. For restoration of affected tree species or for...

M5 model tree based predictive modeling of road accidents on non-urban sections of highways in India.

Science.gov (United States)

Singh, Gyanendra; Sachdeva, S N; Pal, Mahesh

2016-11-01

This work examines the application of M5 model tree and conventionally used fixed/random effect negative binomial (FENB/RENB) regression models for accident prediction on non-urban sections of highway in Haryana (India). Road accident data for a period of 2-6 years on different sections of 8 National and State Highways in Haryana was collected from police records. Data related to road geometry, traffic and road environment related variables was collected through field studies. Total two hundred and twenty two data points were gathered by dividing highways into sections with certain uniform geometric characteristics. For prediction of accident frequencies using fifteen input parameters, two modeling approaches: FENB/RENB regression and M5 model tree were used. Results suggest that both models perform comparably well in terms of correlation coefficient and root mean square error values. M5 model tree provides simple linear equations that are easy to interpret and provide better insight, indicating that this approach can effectively be used as an alternative to RENB approach if the sole purpose is to predict motor vehicle crashes. Sensitivity analysis using M5 model tree also suggests that its results reflect the physical conditions. Both models clearly indicate that to improve safety on Indian highways minor accesses to the highways need to be properly designed and controlled, the service roads to be made functional and dispersion of speeds is to be brought down. Copyright © 2016 Elsevier Ltd. All rights reserved.

ColorTree: a batch customization tool for phylogenic trees.

Science.gov (United States)

Chen, Wei-Hua; Lercher, Martin J

2009-07-31

Genome sequencing projects and comparative genomics studies typically aim to trace the evolutionary history of large gene sets, often requiring human inspection of hundreds of phylogenetic trees. If trees are checked for compatibility with an explicit null hypothesis (e.g., the monophyly of certain groups), this daunting task is greatly facilitated by an appropriate coloring scheme. In this note, we introduce ColorTree, a simple yet powerful batch customization tool for phylogenic trees. Based on pattern matching rules, ColorTree applies a set of customizations to an input tree file, e.g., coloring labels or branches. The customized trees are saved to an output file, which can then be viewed and further edited by Dendroscope (a freely available tree viewer). ColorTree runs on any Perl installation as a stand-alone command line tool, and its application can thus be easily automated. This way, hundreds of phylogenic trees can be customized for easy visual inspection in a matter of minutes. ColorTree allows efficient and flexible visual customization of large tree sets through the application of a user-supplied configuration file to multiple tree files.

Fault tree analysis for urban flooding

NARCIS (Netherlands)

Ten Veldhuis, J.A.E.; Clemens, F.H.L.R.; Van Gelder, P.H.A.J.M.

2008-01-01

Traditional methods to evaluate flood risk mostly focus on storm events as the main cause of flooding. Fault tree analysis is a technique that is able to model all potential causes of flooding and to quantify both the overall probability of flooding and the contributions of all causes of flooding to

COLONIZATION OF PALM TREES BY Rhodnius neglectus AND HOUSEHOLD AND INVASION IN AN URBAN AREA, ARAÇATUBA, SÃO PAULO STATE, BRAZIL

Directory of Open Access Journals (Sweden)

Vera Lúcia Cortiço Corrêa Rodrigues

2014-06-01

Full Text Available The objective of this study is to report on the colonization of palm trees by Rhodnius neglectus, its invasion in an urban area, in Araçatuba - São Paulo, and the control and surveillance measures that have been put in place. Domiciliary triatomine searches occurred in apartments upon the inhabitants' notification. The collected insects were identified and examined for natural infection and food sources with a precipitin test. To search the palm trees, tarps were used to cover the floor, and a “Munck” truck equipped with a tree-pruning device was utilized. Chemical control was performed with the utilization of a manual compression. In 2009, 81 specimens of Rhodnius neglectus were collected from the domiciles by the population. The precipitin test revealed a presence of human blood in 2.7% of the samples. Entomological studies were carried out in these domiciles and in those located within a radius of 200 meters. The search performed in the palm trees resulted in the capture of 882 specimens of triatomines, negative for tripanosomatids. Mechanical and chemical controls were carried out. New searches conducted in the palm trees in the same year resulted in the capture of six specimens. The mechanical and chemical controls of the palm trees, together with the population's work, proved to be effective, therefore preventing these insects' colonization of the city's domiciles.

Potentials of Urban Agriculture in Reflection of “The Thessaloniki Project - Red and Green”

Directory of Open Access Journals (Sweden)

Fáczányi Zsuzsanna

2014-07-01

Full Text Available In spite of the fact the scene of food production is the rural territory; we are witnessing more and more unusual endeavours for farming in cities, additionally in megalopolises. There are numerous researches on the theme, and the new interest in the local cultivation of fruit and vegetable in cities is becoming an earnest factor in urban life in Western Europe, in the USA, and in the Developing World. At the Aristotle University of Thessaloniki, AUTh two professors of architecture managed a course for MSc students of architecture and horticulture, with the intend of designing forms of urban agriculture on a fallow area in Thessaloniki, and considering the crisis situation in Greek. With analysing the proposals of “The Thessaloniki project - Red and Green” parallel with various realized urban agriculture projects I emphasise the force and necessity of the generation of a community

Urbanism Studio 2014

DEFF Research Database (Denmark)

This catalogue showcases the master Urbanism Studio results 2014, which have been developed utilising research on station cities completed by Centre for Strategic Urban Research. Together with the Ministry of Housing, Urban and Rural Affairs (MHURA), UC wished to explore development potentials fo...... to waterflow, from market to stream, from hedge to school garden and from trees to icons. 56 students first developed a list of key strategic proposals from the citizens groups vision papers, followed by specific design answers....

Modeling Ecosystem Services for Park Trees: Sensitivity of i-Tree Eco Simulations to Light Exposure and Tree Species Classification

Directory of Open Access Journals (Sweden)

Rocco Pace

2018-02-01

Full Text Available Ecosystem modeling can help decision making regarding planting of urban trees for climate change mitigation and air pollution reduction. Algorithms and models that link the properties of plant functional types, species groups, or single species to their impact on specific ecosystem services have been developed. However, these models require a considerable effort for initialization that is inherently related to uncertainties originating from the high diversity of plant species in urban areas. We therefore suggest a new automated method to be used with the i-Tree Eco model to derive light competition for individual trees and investigate the importance of this property. Since competition depends also on the species, which is difficult to determine from increasingly used remote sensing methodologies, we also investigate the impact of uncertain tree species classification on the ecosystem services by comparing a species-specific inventory determined by field observation with a genus-specific categorization and a model initialization for the dominant deciduous and evergreen species only. Our results show how the simulation of competition affects the determination of carbon sequestration, leaf area, and related ecosystem services and that the proposed method provides a tool for improving estimations. Misclassifications of tree species can lead to large deviations in estimates of ecosystem impacts, particularly concerning biogenic volatile compound emissions. In our test case, monoterpene emissions almost doubled and isoprene emissions decreased to less than 10% when species were estimated to belong only to either two groups instead of being determined by species or genus. It is discussed that this uncertainty of emission estimates propagates further uncertainty in the estimation of potential ozone formation. Overall, we show the importance of using an individual light competition approach and explicitly parameterizing all ecosystem functions at the

Constructing New York City's urban forest. The politics and governance of the MillionTreesNYC campaign

Science.gov (United States)

Lindsay K. Campbell

2014-01-01

In 2005-2006, bureaucrats at the New York City Department of Parks and Recreation (DPR) began to marshal quantitative evidence to argue for investment in tree planting as part of Mayor Bloomberg's long-term sustainability plan, PlaNYC 2030, launched in 2007. Concurrently, Bette Midler—the celebrity founder of the non-profit New York Restoration Project (...

Combining tree-ring metal concentrations and lead, carbon and oxygen isotopes to reconstruct peri-urban atmospheric pollution

Directory of Open Access Journals (Sweden)

Annick Doucet

2012-08-01

Full Text Available In this study, we analysed the tree-ring metal concentrations and isotope ratios of five stands located in three contrasted settings to infer the diffuse air pollution history of the northern part of the Windsor–Québec City Corridor in eastern Canada. Tree-ring series show that the Cd and Zn accumulation rates were higher between 1960 and 1986 and that the long-term acidification of the soil (Ca/Al series was likely induced by NOx and SOx deposition (δ15N and δ13C trends as proxy. The Pb concentrations and 206Pb/207Pb ratios indicate that the dominant source of lead from 1880 to the 1920s was the combustion of north-eastern American coal, which was succeeded by the combustion of leaded gasoline from the 1920s to the end of the 1980s. Our modelling approach allows separating the climatic and anthropogenic effects on the tree-ring δ13C and δ18O responses. Diffuse air pollution caused an enrichment in 13C in all stands and a decrease of the δ18O values only in three of the stands. This study indicates that dendrogeochemistry can show contrasted responses to environmental changes and that the combination of several independent indicators constitutes a powerful tool to reconstruct the air pollution history in the complex context of peri-urban regions.

Introduction to Urban and Community Forestry in the United States of America: History, Accomplishments, Issues and Trends

Institute of Scientific and Technical Information of China (English)

Qi Yadong; Zhang Zhiqiang

2003-01-01

The urban and community forestry movement in the United States has matured over the last 20 years from managing street trees, to understanding the benefits of trees in urban ecosystems, and now to managing urban green infrastructure. This paper introduced the history, development, and major accomplishments of the urban and community forestry movement, highlighted the economic, ecological, environmental, and social values of forests and trees to communities, and discussed issues and trends of the urban and community forestry program in the United States.

Dry tree semisubmersible platform: from 'technology accepted' to 'project ready'

Energy Technology Data Exchange (ETDEWEB)

Lu, Roger; Wang, Tao; Nygaard, Magne; Bendiksen, Rolf [Aker Solutions, Oslo (Norway)

2012-07-01

Development of new technologies for application of dry tree solutions on semi-submersible hull production platforms opens up new flexible and cost efficient solutions for oil and gas fields in deep and ultra deep water. Aker Solutions has brought the technology through the last steps to a project ready stage. Top tension risers allow for shifting the Christmas tree from seabed to topside, and enables drilling and production from the same unit. By shifting the wellhead and Christmas tree from seabed to platform deck, well maintenance is simplified, and makes the Dry Tree Semi relevant to consider for the Brazilian pre-salt reservoirs. Easy access to the wells for maintenance gives a potential for a higher recovery rate for the field. Future development of ultra deep water oil and gas fields demands solutions overcoming the limitations set by the TLP and the Spar buoy. Combining knowledge from already proven solutions, and a limited addition of new technology, these limitations are overcome with Aker Solutions' Dry Tree Semi. It is designed and proven for Gulf of Mexico environmental conditions. It is verified for conditions with a significant wave height of 14 meters, and able to withstand 100-year extreme weather and 1000-years survival conditions. A conventional semi-submersible platform, but with a deeper draft to further reduce the already low motions, makes the basis for the concept. Top tensioned risers (TTR) with vertical motion compensation stroke of up to 10 meters, makes it possible to shift the Christmas tree from seabed to platform deck. The deep draft design of the hull reduces the wave force excitation on the pontoons, reducing both the roll and pitch dynamics. The Dry Tree Semi represents several major benefits, including low sensitivity to water depth, reduced hull and topside weight, and flexibility in transportation, mooring, and decommissioning. (author)

DupTree: a program for large-scale phylogenetic analyses using gene tree parsimony.

Science.gov (United States)

Wehe, André; Bansal, Mukul S; Burleigh, J Gordon; Eulenstein, Oliver

2008-07-01

DupTree is a new software program for inferring rooted species trees from collections of gene trees using the gene tree parsimony approach. The program implements a novel algorithm that significantly improves upon the run time of standard search heuristics for gene tree parsimony, and enables the first truly genome-scale phylogenetic analyses. In addition, DupTree allows users to examine alternate rootings and to weight the reconciliation costs for gene trees. DupTree is an open source project written in C++. DupTree for Mac OS X, Windows, and Linux along with a sample dataset and an on-line manual are available at http://genome.cs.iastate.edu/CBL/DupTree

A Cross-Curricular, Problem-Based Project to Promote Understanding of Poverty in Urban Communities

Science.gov (United States)

Gardner, Daniel S.; Tuchman, Ellen; Hawkins, Robert

2010-01-01

This article describes the use of problem-based learning to teach students about the scope and consequences of urban poverty through an innovative cross-curricular project. We illustrate the process, goals, and tasks of the Community Assessment Project, which incorporates community-level assessment, collection and analysis of public data, and…

Individual tree crown modeling and change detection from airborne lidar data

NARCIS (Netherlands)

Xiao, W.; Xu, Sudan; Oude Elberink, S.J.; Vosselman, G.

2016-01-01

Light detection and ranging (lidar) provides a promising way of detecting changes of trees in three-dimensional (3-D) because laser beams can penetrate through the foliage and therefore provide full coverage of trees. The aim is to detect changes in trees in urban areas using multitemporal airborne

EVALUATION OF THE WORK CONDITIONS OF ACTIVITIES OF URBAN TREE PRUNING

Directory of Open Access Journals (Sweden)

Nilton César Fiedler

2007-03-01

Full Text Available this work analyzed the work environment in the trees pruning activities in the urban arborization, comparison with the values of the legislation and the practical application of results to provide a better comfort, security, health, welfare to workers, and also a better efficiency and quality of the work. The weather conditions, the noise levels, the light conditions and vibration were analyzed using suitable ergonomic methods. The weather conditions in the work environment were according the permissible values in the legislation (NR15 for index of humid bulb and globe thermometer (IBUTG of 25°C for the activities of pruning, with exception of the schedule to twelve hours (26,2°C, the hours of working should be of 30 minutes of work and 30 minutes of rest. The noise levels found in the activities of cut were 105,7 dB (A and bucking were 103.9 dB (A, above the level permited by legislation (NR15. The minimum light conditions values were acceptable for legislation (NBR 5413/92, but the global indices were too high being able to cause problems to the worker health. The vibration conditions were acceptable.

Performance testing to identify climate-ready trees

Science.gov (United States)

E.Gregory McPherson; Alison M. Berry; Natalie S. van Doorn

2018-01-01

Urban forests produce ecosystem services that can benefit city dwellers, but are especially vulnerable to climate change stressors such as heat, drought, extreme winds and pests. Tree selection is an important decision point for managers wanting to transition to a more stable and resilient urban forest structure. This study describes a five-step process to identify and...

Urban trees and the risk of poor birth outcomes

Science.gov (United States)

Geoffrey H. Donovan; Yvonne L. Michael; David T. Butry; Amy D. Sullivan; John M. Chase

2011-01-01

This paper investigated whether greater tree-canopy cover is associated with reduced risk of poor birth outcomes in Portland, Oregon. Residential addresses were geocoded and linked to classified-aerial imagery to calculate tree-canopy cover in 50, 100, and 200 m buffers around each home in our sample (n=5696). Detailed data on maternal characteristics and additional...

Research project on “A Study in Urban Air Pollution Improvement in Asia”

OpenAIRE

2017-01-01

This final report of the joint research project “A study in urban air pollution improvement in Asia” is submitted by the Asian Institute of Technology (AIT) on behalf of the project team following the contract between AIT and the Japan International Cooperation Agency (JICA) for the project period of March 2015 - December 2017. Technical support is provided by the Asia Center for Air Pollution Research (ACAP) Japan and the operational support is provided by the Pollution Control Department (P...

Assessing Urban Forest Structure, Ecosystem Services, and Economic Benefits on Vacant Land

Directory of Open Access Journals (Sweden)

Gunwoo Kim

2016-07-01

Full Text Available An urban forest assessment is essential for developing a baseline from which to measure changes and trends. The most precise way to assess urban forests is to measure and record every tree on a site, but although this may work well for relatively small populations (e.g., street trees, small parks, it is prohibitively expensive for large tree populations. Thus, random sampling offers a cost-effective way to assess urban forest structure and the associated ecosystem services for large-scale assessments. The methodology applied to assess ecosystem services in this study can also be used to assess the ecosystem services provided by vacant land in other urban contexts and improve urban forest policies, planning, and the management of vacant land. The study’s findings support the inclusion of trees on vacant land and contribute to a new vision of vacant land as a valuable ecological resource by demonstrating how green infrastructure can be used to enhance ecosystem health and promote a better quality of life for city residents.

Factors Influencing the Private Involvement in Urban Rail Public-Private Partnership Projects in China

Directory of Open Access Journals (Sweden)

Yongjian Ke

2017-03-01

Full Text Available Private investors have been encouraged to participate in the development and operation of urban rail projects in China through Public-Private Partnerships (PPPs, given the fact that subnational governments are suffering from urgent development demands and severe fiscal pressure. However, there is no formal assessment to determine the private involvement in a PPP project. This problem is particularly critical in the sector of urban rail, in which the huge investment cannot rely on the private sector alone. This study hence aimed to uncover and identify the influencing factors. Multiple research methods, including content analysis, case study and focus group discussion were adopted to achieve the research purpose. Seven types of influencing factors were identified, including project financial model, government fiscal commitment, risk allocation, public accountability, efficiency considerations, policy and regulations, and organisational marketing strategies. The findings add to the current knowledge base by uncovering the drivers behind private involvement in a PPP project. They are also beneficial for industry practitioners as a basis/checklist to determine the private involvement.

City of Boulder, Colorado Municipal Tree Resource Analysis

Science.gov (United States)

E.G. McPherson; J.R. Simpson; P.J. Peper; S.L. Gardner; K.E. Vargas; Q. Xiao

2005-01-01

Boulder is a vibrant city, renowned for its livability and cultural wealth and well known for its Smart Growth policies that protect and restore environmental quality while enhancing economic opportunity. The city maintains trees as an integral component of the urban infrastructure. Research indicates that healthy trees can mitigate impacts associated with the built...

Orange Is the New Green: Exploring the Restorative Capacity of Seasonal Foliage in Schoolyard Trees

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Eli Paddle

2016-05-01

Full Text Available Urban schoolyard environments are increasingly characterized by a proliferation of hard surfaces with little if any greenery. Schoolyard “greening” initiatives are becoming increasingly popular; however, schoolyard designs often fail to realize their restorative potential. In this quasi-experimental study, a proposed schoolyard greening project was used to visualize alternative planting designs and seasonal tree foliage; these design alternatives were subsequently used as visual stimuli in a survey administered to children who will use the schoolyard to assess the perceived restorative capacity of different design features. The findings indicate that seasonal changes in tree foliage enhance the perceived restorative quality of schoolyard environments. Specifically, fall foliage colour, when compared to green foliage, is rated as being perceived to be equally restorative for children. Additionally, seasonal planting, including evergreen conifers, may enhance the restorative quality of the schoolyard especially when deciduous trees are leafless. Landscape design professionals, community-based organizations, and other decision-makers in schoolyard greening efforts should strategically consider their tree choices to maximize year-round support for healthy attention functioning in children through restoration.

The marginal cost of carbon abatement from planting street trees in New York City

Science.gov (United States)

Kent F. Kovacs; Robert G. Haight; Suhyun Jung; Dexter H. Locke; Jarlath. O' Neil-Dunne

2013-01-01

Urban trees can store carbon through the growth process and reduce fossil fuel use by lowering cooling and heating energy consumption of buildings through the process of transpiration, shading, and the blocking of wind. However, the planting and maintenance of urban trees come at a cost. We estimate the discounted cost of net carbon reductions associated with planting...

The Urban Environmental Monitoring/100 Cities Project: Legacy of the First Phase and Next Steps

Science.gov (United States)

Stefanov, William L.; Wentz, Elizabeth A.; Brazel, Anthony; Netzband, Maik; Moeller, Matthias

2009-01-01

The Urban Environmental Monitoring (UEM) project, now known as the 100 Cities Project, at Arizona State University (ASU) is a baseline effort to collect and analyze remotely sensed data for 100 urban centers worldwide. Our overarching goal is to use remote sensing technology to better understand the consequences of rapid urbanization through advanced biophysical measurements, classification methods, and modeling, which can then be used to inform public policy and planning. Urbanization represents one of the most significant alterations that humankind has made to the surface of the earth. In the early 20th century, there were less than 20 cities in the world with populations exceeding 1 million; today, there are more than 400. The consequences of urbanization include the transformation of land surfaces from undisturbed natural environments to land that supports different forms of human activity, including agriculture, residential, commercial, industrial, and infrastructure such as roads and other types of transportation. Each of these land transformations has impacted, to varying degrees, the local climatology, hydrology, geology, and biota that predate human settlement. It is essential that we document, to the best of our ability, the nature of land transformations and the consequences to the existing environment. The focus in the UEM project since its inception has been on rapid urbanization. Rapid urbanization is occurring in hundreds of cities worldwide as population increases and people migrate from rural communities to urban centers in search of employment and a better quality of life. The unintended consequences of rapid urbanization have the potential to cause serious harm to the environment, to human life, and to the resulting built environment because rapid development constrains and rushes decision making. Such rapid decision making can result in poor planning, ineffective policies, and decisions that harm the environment and the quality of human life

Implications of tree planting on pollutant dispersion in street canyons

NARCIS (Netherlands)

Gromke, C.B.; Ruck, B.

2009-01-01

Traffic pollutant dispersion processes inside urban street canyons with avenue-like tree planting have been studied in wind tunnel experiments. Tree planting of different crown porosities and their effects on the pollutant concentrations at the canyon walls have been investigated for wind

A Voxel-Based Method for Automated Identification and Morphological Parameters Estimation of Individual Street Trees from Mobile Laser Scanning Data

Directory of Open Access Journals (Sweden)

Hongxing Liu

2013-01-01

Full Text Available As an important component of urban vegetation, street trees play an important role in maintenance of environmental quality, aesthetic beauty of urban landscape, and social service for inhabitants. Acquiring accurate and up-to-date inventory information for street trees is required for urban horticultural planning, and municipal urban forest management. This paper presents a new Voxel-based Marked Neighborhood Searching (VMNS method for efficiently identifying street trees and deriving their morphological parameters from Mobile Laser Scanning (MLS point cloud data. The VMNS method consists of six technical components: voxelization, calculating values of voxels, searching and marking neighborhoods, extracting potential trees, deriving morphological parameters, and eliminating pole-like objects other than trees. The method is validated and evaluated through two case studies. The evaluation results show that the completeness and correctness of our method for street tree detection are over 98%. The derived morphological parameters, including tree height, crown diameter, diameter at breast height (DBH, and crown base height (CBH, are in a good agreement with the field measurements. Our method provides an effective tool for extracting various morphological parameters for individual street trees from MLS point cloud data.

Visualizing phylogenetic tree landscapes.

Science.gov (United States)

Wilgenbusch, James C; Huang, Wen; Gallivan, Kyle A

2017-02-02

Genomic-scale sequence alignments are increasingly used to infer phylogenies in order to better understand the processes and patterns of evolution. Different partitions within these new alignments (e.g., genes, codon positions, and structural features) often favor hundreds if not thousands of competing phylogenies. Summarizing and comparing phylogenies obtained from multi-source data sets using current consensus tree methods discards valuable information and can disguise potential methodological problems. Discovery of efficient and accurate dimensionality reduction methods used to display at once in 2- or 3- dimensions the relationship among these competing phylogenies will help practitioners diagnose the limits of current evolutionary models and potential problems with phylogenetic reconstruction methods when analyzing large multi-source data sets. We introduce several dimensionality reduction methods to visualize in 2- and 3-dimensions the relationship among competing phylogenies obtained from gene partitions found in three mid- to large-size mitochondrial genome alignments. We test the performance of these dimensionality reduction methods by applying several goodness-of-fit measures. The intrinsic dimensionality of each data set is also estimated to determine whether projections in 2- and 3-dimensions can be expected to reveal meaningful relationships among trees from different data partitions. Several new approaches to aid in the comparison of different phylogenetic landscapes are presented. Curvilinear Components Analysis (CCA) and a stochastic gradient decent (SGD) optimization method give the best representation of the original tree-to-tree distance matrix for each of the three- mitochondrial genome alignments and greatly outperformed the method currently used to visualize tree landscapes. The CCA + SGD method converged at least as fast as previously applied methods for visualizing tree landscapes. We demonstrate for all three mtDNA alignments that 3D

The balance of planting and mortality in a street tree population

Science.gov (United States)

Lara A. Roman; John J. Battles; Joe R. McBride

2013-01-01

Street trees have aesthetic, environmental, human health, and economic benefits in urban ecosystems. Street tree populations are constructed by cycles of planting, growth, death, removal and replacement. The goals of this study were to understand how tree mortality and planting rates affect net population growth, evaluate the shape of the mortality curve, and assess...

The national tree-list layer

Science.gov (United States)

Stacy A. Drury; Jason M. Herynk

2011-01-01

The National Tree-List Layer (NTLL) project used LANDFIRE map products to produce the first national tree-list map layer that represents tree populations at stand and regional levels. The NTLL was produced in a short time frame to address the needs of Fire and Aviation Management for a map layer that could be used as input for simulating fire-caused tree mortality...

Case study: Rainfall partitioning across a natural-to-urban forest gradient during an extreme rain event

Science.gov (United States)

Akin, B. H.; Van Stan, J. T., II; Cote, J. F.; Jarvis, M. T.; Underwood, J.; Friesen, J.; Hildebrandt, A.; Maldonado, G.

2017-12-01

Trees' partitioning of rainfall is an important first process along the rainfall-to-runoff pathway that has economically significant influences on urban stormwater management. However, important knowledge gaps exist regarding (1) its role during extreme storms and (2) how this role changes as forest structure is altered by urbanization. Little research has been conducted on canopy rainfall partitioning during large, intense storms, likely because canopy water storage is rapidly overwhelmed (i.e., 1-3 mm) by short duration events exceeding, for example, 80 mm of rainfall. However, canopy structure controls more than just storage; it also affects the time for rain to drain to the surface (becoming throughfall) and the micrometeorological conditions that drive wet canopy evaporation. In fact, observations from an example extreme ( 100 mm with maximum 5-minute intensities exceeding 55 mm/h) storm across a urban-to-natural gradient in pine forests in southeast Georgia (USA), show that storm intensities were differentially dampened by 33% (tree row), 28% (forest fragment), and 17% (natural forests). In addition, maximum wet canopy evaporation rates were higher for the exposed tree row (0.18 mm/h) than for the partially-enclosed fragment canopy (0.14 mm/h) and the closed canopy natural forest site (0.11). This resulted in interception percentages decreasing from urban-to-natural stand structures (25% to 16%). A synoptic analysis of the extreme storm in this case study also shows that the mesoscale meteorological conditions that developed the heavy rainfall is expected to occur more often with projected climate changes.

Structuring institutional analysis for urban ecosystems: A key to sustainable urban forest management

Science.gov (United States)

Sarah K. Mincey; Miranda Hutten; Burnell C. Fischer; Tom P. Evans; Susan I. Stewart; Jessica M. Vogt

2013-01-01

A decline in urban forest structure and function in the United States jeopardizes the current focus on developing sustainable cities. A number of social dilemmas—for example, free-rider problems—restrict the sustainable production of ecosystem services and the stock of urban trees from which they flow. However, institutions, or the rules, norms, and strategies that...

Automatic fault tree generation in the EPR PSA project

International Nuclear Information System (INIS)

Villatte, N; Nonclercq, P.; Taupy, S.

2012-01-01

Tools (KB3 and Atelier EPS) have been developed at EDF to assist the analysts in building fault trees for PSA (Probabilistic Safety Assessment) and importing them into RiskSpectrum (RiskSpectrum is a Swedish code used at EDF for PSA). System modelling is performed using KB3 software with a knowledge base describing generic classes of components with their behaviour and failure modes. Using these classes of components, the analyst can describe (using a graphical system editor): a simplified system diagram from the mechanical system drawings and functional descriptions, the missions of the studied system (in a form of high level fault trees) and its different configurations for the missions. He can also add specific knowledge about the system. Then, the analyst chooses missions and configurations to specify and launch fault trees generations. From the system description, KB3 produces by backward-chaining on rules, detailed system fault trees. These fault trees are finally imported into RiskSpectrum (they are converted by Atelier EPS into a format readable by RiskSpectrum). KB3 and Atelier EPS have been used to create the majority of the fault trees for the EDF EPR Probabilistic Safety Analysis conducted from November 2009 to March 2010. 25 systems were modelled, and 127 fault trees were automatically generated in a rather short time by different analysts with the help of these tools. A feedback shows a lot of advantages to use KB3 and Atelier EPS: homogeneity and consistency between the different generated fault trees, traceability of modelling, control of modelling and last but not least: the automation of detailed fault tree creation relieves the human analyst of this tedious task so that he can focus his attention on more important tasks: modelling the failure of a function. This industrial application has also helped us gather an interesting feedback from the analysts that should help us improve the handling of the tools. We propose in this paper indeed some

Remote sensing assessment of carbon storage by urban forest

International Nuclear Information System (INIS)

Kanniah, K D; Kang, C S; Muhamad, N

2014-01-01

Urban forests play a crucial role in mitigating global warming by absorbing excessive CO 2 emissions due to transportation, industry and house hold activities in the urban environment. In this study we have assessed the role of trees in an urban forest, (Mutiara Rini) located within the Iskandar Development region in south Johor, Malaysia. We first estimated the above ground biomass/carbon stock of the trees using allometric equations and biometric data (diameter at breast height of trees) collected in the field. We used remotely sensed vegetation indices (VI) to develop an empirical relationship between VI and carbon stock. We used five different VIs derived from a very high resolution World View-2 satellite data. Results show that model by [1] and Normalized Difference Vegetation Index are correlated well (R 2 = 0.72) via a power model. We applied the model to the entire study area to obtain carbon stock of urban forest. The average carbon stock in the urban forest (mostly consisting of Dipterocarp species) is ∼70 t C ha −1 . Results of this study can be used by the Iskandar Regional Development Authority to better manage vegetation in the urban environment to establish a low carbon city in this region

Does urban vegetation mitigate air pollution in northern conditions?

International Nuclear Information System (INIS)

Setälä, Heikki; Viippola, Viljami; Rantalainen, Anna-Lea; Pennanen, Arto; Yli-Pelkonen, Vesa

2013-01-01

It is generally accepted that urban vegetation improves air quality and thereby enhances the well-being of citizens. However, empirical evidence on the potential of urban trees to mitigate air pollution is meager, particularly in northern climates with a short growing season. We studied the ability of urban park/forest vegetation to remove air pollutants (NO 2 , anthropogenic VOCs and particle deposition) using passive samplers in two Finnish cities. Concentrations of each pollutant in August (summer; leaf-period) and March (winter, leaf-free period) were slightly but often insignificantly lower under tree canopies than in adjacent open areas, suggesting that the role of foliage in removing air pollutants is insignificant. Furthermore, vegetation-related environmental variables (canopy closure, number and size of trees, density of understorey vegetation) did not explain the variation in pollution concentrations. Our results suggest that the ability of urban vegetation to remove air pollutants is minor in northern climates. -- Highlights: ► The ability of northern urban vegetation to remove air pollutants is minor. ► Vegetation-related environmental variables had no effect on air pollution levels. ► The ability of vegetation to clean air did not differ between summer and winter. ► Dry deposition passive samplers proved applicable in urban air pollution study. -- The ability of urban vegetation to remove air pollutants seems to be minor in northern climates

Risk management of PPP project in the preparation stage based on Fault Tree Analysis

Science.gov (United States)

Xing, Yuanzhi; Guan, Qiuling

2017-03-01

The risk management of PPP(Public Private Partnership) project can improve the level of risk control between government departments and private investors, so as to make more beneficial decisions, reduce investment losses and achieve mutual benefit as well. Therefore, this paper takes the PPP project preparation stage venture as the research object to identify and confirm four types of risks. At the same time, fault tree analysis(FTA) is used to evaluate the risk factors that belong to different parts, and quantify the influencing degree of risk impact on the basis of risk identification. In addition, it determines the importance order of risk factors by calculating unit structure importance on PPP project preparation stage. The result shows that accuracy of government decision-making, rationality of private investors funds allocation and instability of market returns are the main factors to generate the shared risk on the project.

INDIVIDUAL TREE OF URBAN FOREST EXTRACTION FROM VERY HIGH DENSITY LIDAR DATA

Directory of Open Access Journals (Sweden)

A. Moradi

2016-06-01

Full Text Available Airborne LiDAR (Light Detection and Ranging data have a high potential to provide 3D information from trees. Most proposed methods to extract individual trees detect points of tree top or bottom firstly and then using them as starting points in a segmentation algorithm. Hence, in these methods, the number and the locations of detected peak points heavily effect on the process of detecting individual trees. In this study, a new method is presented to extract individual tree segments using LiDAR points with 10cm point density. In this method, a two-step strategy is performed for the extraction of individual tree LiDAR points: finding deterministic segments of individual trees points and allocation of other LiDAR points based on these segments. This research is performed on two study areas in Zeebrugge, Bruges, Belgium (51.33° N, 3.20° E. The accuracy assessment of this method showed that it could correctly classified 74.51% of trees with 21.57% and 3.92% under- and over-segmentation errors respectively.

Morocco - Fruit Tree Productivity

Data.gov (United States)

Millennium Challenge Corporation — Date Tree Irrigation Project: The specific objectives of this evaluation are threefold: - Performance evaluation of project activities, like the mid-term evaluation,...

To treat or not to treat: Diminishing effectiveness of emamectin benzoate tree injections in ash trees heavily infested by emerald ash borer

Science.gov (United States)

Charles E. Flower; Jennifer E. Dalton; Kathleen S. Knight; Marie Brikha; Miquel A. Gonzalez-Meler

2015-01-01

Emerald ash borer (EAB), a non-native invasive tree-boring beetle, is the primary agent behind thewidespread mortality of ash trees (Fraxinus spp.) in both natural forests and urban areas of North Amer-ica. While a variety of insecticide options have been adopted for protection against EAB attacks, little hasbeen reported on the success of...

Experiences and Challenges of Community Participation in Urban Renewal Projects: The Case of Johannesburg, South Africa

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Wellington Didibhuku Thwala

2009-11-01

Full Text Available Urban renewal and inner city regeneration have become critical efforts for the South African government, which has invested in several structures to stem the tide of decline in its nine major cities. Commitment to the alleviation of poverty is a focal point of the renewal and regeneration agenda and will remain so in the future. This effort is motivated by the fact that around 24% of the South African population currently lives on less than USD 1.00 per day, below the poverty line defined by the World Bank. The Central Government has made numerous public commitments to development, a part of which concerns extensive infrastructure investment and service delivery. Communities are expected to participate fully in the planning and implementation of these urban renewal projects. To this aim, participation is a process through which stakeholders influence and share control over development initiatives and the decisions and resources which affect them. Community participation should be aimed at empowering people by ensuring the development of skills and the creation of employment opportunities. This paper first explores the concept of community participation, and will then look at relevant past experiences in relation to community participation in urban renewal projects. Furthermore, the paper outlines the challenges and problems of community participation in urban renewal projects in Johannesburg, and finally, close with recommendations for the future.

Proceedings of the 6. Canadian Urban Forest Conference : fires, storms, and pests : crisis in our urban forests

Energy Technology Data Exchange (ETDEWEB)

NONE

2006-07-01

There is an increasing awareness in Canada of the benefits and values of urban forests in environmental, social and economic terms. However, the mountain pine beetle (MPB) infestation in British Columbia (BC) has infected vast tracts of the province's forest lands over the last several years, and there is evidence that the beetle plague is now causing major devastation in urban areas. Fires are increasing in size and moving from surrounding forest lands into towns and cities in the province and have taken a toll on people and properties in urban areas. Storms and hurricanes have imposed damage on trees in urban areas in the Maritimes, Quebec and Ontario. This conference presented strategies for urban forest managers faced with a variety of disturbances. Issues concerning emergency preparedness and the role of utilities in urban forestry matters were examined and tools for valuing and marketing the urban forest were reviewed. Landscaping for the mitigation of fires was discussed along with tree hazard assessment techniques. The positive financial impact made to communities by their urban forests was emphasized and guidelines and support tools to help municipalities maintain and enhance their urban forests were outlined. The establishment of research priorities for urban forestry was recommended, as well as the identification of unique and threatened habitats both in, and near, large and small municipalities. Twenty-four presentations were given at this conference, of which 3 have been catalogued separately for inclusion in this database. refs., tabs., figs.

Planting forests in NYC: Is the goal restoration, reforestation, or afforestation?

Science.gov (United States)

R.A. Hallett

2013-01-01

Chicago, Los Angeles, Philadelphia, Detroit, New York City (NYC) and many other cities in the United States and around the world are engaging in urban greening projects. Urban greening almost always involves planting trees... lots of trees. New York City, for example, has planted over 750,000 trees to date as part of a project that started in 2007 – a project with the...

Examining Volunteer Motivations and Recruitment Strategies For Engagement in Urban Forestry

Directory of Open Access Journals (Sweden)

Christine Moskell

2010-01-01

Full Text Available Few studies in urban forestry have examined the motivations of urban forestry volunteers. In this research, two social psychological theories (Volunteer Functions Inventory and Volunteer Process Model are utilized to examine motivations for participating in tree planting activities. The Volunteer Functions Inventory can be used to examine the needs, goals and motivations that individuals seek to fulfill through volunteerism. The Volunteer Process Model sheds light on the antecedents, experiences and consequences of volunteerism at multiple levels (individual, interpersonal, organizational, societal. An understanding of volunteer motivations can aid practitioners in the development and implementation of participatory urban forestry programs that are attractive to stakeholders. We conducted a survey of volunteers who participated in a MillionTreesNYC volunteer planting event and a focus group of urban forestry practitioners. Survey results reveal that volunteers have varied motivations and a limited knowledge of the community level impacts of trees. Results from the focus group reveal that providing education about the benefits of trees and maintaining long-term communication with volunteers are frequently used strategies for engagement. However, the public’s lack of knowledge about urban forestry and an inability to connect to audiences are practitioner-identified challenges for recruiting stakeholders to participate in their programs.

Landscaping and landscape ecology in the management of tree plantation. A reference to the city of Medellin, Colombia

International Nuclear Information System (INIS)

Velez Restrepo, Luis Anibal

2007-01-01

The paper constitutes a reflection around the urban landscape, whit reference to Medellin, likewise around the landscaping and ecological potential that the city has along its terrain, its empty lots, without urbanizing, and especially, thanks to the tree plantation that its streets display. It is questioned the absence of a landscaping dimension in the urban planning; the increasing deterioration of the panoramic qualities; and the gradual loss of green spaces. At the same time, it is emphasized the importance that such tree planting has in the landscape, from the visual, social and environmental point of view. The work discusses the tendency to the artificiality of tree planting on sidewalks and vial road separators, raising conceptual limitations associated to the scale tree to tree, to the lack of incorporation of ecological landscape relations related to its handling, and to the landscaping approach within the framework of the urban designing. The reflection leans on data of the concrete situation, suggesting the complementary role that the vegetation could accomplish in streets and avenues with a perspective of ecological connectivity of the landscape

The role of composition, invasives, and maintenance emissions on urban forest carbon stocks.

Science.gov (United States)

Horn, Josh; Escobedo, Francisco J; Hinkle, Ross; Hostetler, Mark; Timilsina, Nilesh

2015-02-01

There are few field-based, empirical studies quantifying the effect of invasive trees and palms and maintenance-related carbon emissions on changes in urban forest carbon stocks. We estimated carbon (C) stock changes and tree maintenance-related C emissions in a subtropical urban forest by re-measuring a subsample of residential permanent plots during 2009 and 2011, using regional allometric biomass equations, and surveying residential homeowners near Orlando, FL, USA. The effect of native, non-native, invasive tree species and palms on C stocks and sequestration was also quantified. Findings show 17.8 tC/ha in stocks and 1.2 tC/ha/year of net sequestration. The most important species both by frequency of C stocks and sequestration were Quercus laurifolia Michx. and Quercus virginiana Mill., accounting for 20% of all the trees measured; 60% of carbon stocks and over 75% of net C sequestration. Palms contributed to less than 1% of the total C stocks. Natives comprised two-thirds of the tree population and sequestered 90% of all C, while invasive trees and palms accounted for 5 % of net C sequestration. Overall, invasive and exotic trees had a limited contribution to total C stocks and sequestration. Annual tree-related maintenance C emissions were 0.1% of total gross C sequestration. Plot-level tree, palm, and litter cover were correlated to C stocks and net sequestration. Findings can be used to complement existing urban forest C offset accounting and monitoring protocols and to better understand the role of invasive woody plants on urban ecosystem service provision.

Interpreting Sustainability for Urban Forests

Directory of Open Access Journals (Sweden)

Camilo Ordóñez

2010-06-01

Full Text Available Incisive interpretations of urban-forest sustainability are important in furthering our understanding of how to sustain the myriad values associated with urban forests. Our analysis of earlier interpretations reveals conceptual gaps. These interpretations are attached to restrictive definitions of a sustainable urban forest and limited to a rather mechanical view of maintaining the biophysical structure of trees. The probing of three conceptual domains (urban forest concepts, sustainable development, and sustainable forest management leads to a broader interpretation of urban-forest sustainability as the process of sustaining urban forest values through time and across space. We propose that values—and not services, benefits, functions or goods—is a superior concept to refer to what is to be sustained in and by an urban forest.

The dust retention capacities of urban vegetation-a case study of Guangzhou, South China.

Science.gov (United States)

Liu, Lu; Guan, Dongsheng; Peart, M R; Wang, Gang; Zhang, Hui; Li, Zhiwei

2013-09-01

Urban vegetation increasingly plays an important role in the improvement of the urban atmospheric environment. This paper deals with the dust retention capacities of four urban tree species (Ficus virens var. sublanceolata, Ficus microcarpa, Bauhinia blakeana, and Mangifera indica Linn) in Guangzhou. The dust-retaining capacities of four tree species are studied under different pollution intensities and for different seasons. Remote sensing imagery was used to estimate the total aboveground urban vegetation biomass in different functional areas of urban Guangzhou, information that was then used to estimate the dust-retaining capacities of the different functional areas and the total removal of airborne particulates in urban Guangzhou by foliage. The results showed that urban vegetation can remove dust from the atmosphere thereby improving air quality. The major findings are that dust retention, or capture, vary between the four species of tree studied; it also varied between season and between types of urban functional area, namely industrial, commercial/road traffic, residential, and clean areas. Dust accumulation over time was also studied and reached a maximum, and saturation, after about 24 days. The overall aboveground biomass of urban vegetation in Guangzhou was estimated to be 52.0 × 10(5) t, its total leaf area 459.01 km(2), and the dust-retaining capacity was calculated at 8012.89 t per year. The present study demonstrated that the foliage of tree species used in urban greening make a substantial contribution to atmospheric dust removal and retention in urban Guangzhou.