A comparison of fungal endophytic community diversity in tree leaves of rural and urban temperate forests of Kanto district, eastern Japan.

PubMed

Matsumura, Emi; Fukuda, Kenji

2013-03-01

To clarify the effects of forest fragmentation and a change in tree species composition following urbanization on endophytic fungal communities, we isolated fungal endophytes from the foliage of nine tree species in suburban (Kashiwa City, Chiba) and rural (Mt. Wagakuni, Ibaraki; Mt. Takao, Tokyo) forests and compared the fungal communities between sites and host tree species. Host specificity was evaluated using the index of host specificity (Si), and the number of isolated species, total isolation frequency, and the diversity index were calculated. From just one to several host-specific species were recognized in all host tree species at all sites. The total isolation frequency of all fungal species on Quercus myrsinaefolia, Quercus serrata, and Chamaecyparis obtusa and the total isolation frequency of host-specific species on Q. myrsinaefolia, Q. serrata, and Eurya japonica were significantly lower in Kashiwa than in the rural forests. The similarity indices (nonmetric multidimensional scaling (NMS) and CMH) of endophytic communities among different tree species were higher in Kashiwa, as many tree species shared the same fungal species in the suburban forest. Endophytic fungi with a broad host range were grouped into four clusters suggesting their preference for conifer/broadleaves and evergreen/deciduous trees. Forest fragmentation and isolation by urbanization have been shown to cause the decline of host-specific fungal species and a decrease in β diversity of endophytic communities, i.e., endophytic communities associated with tree leaves in suburban forests were found to be depauperate. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Street trees reduce the negative effects of urbanization on birds

PubMed Central

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 consequently improve human wellbeing and quality of life. PMID:28333989

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

Treesearch

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),...

Housing Shortages in Urban Regions: Aggressive Interactions at Tree Hollows in Forest Remnants

PubMed Central

Davis, Adrian; Major, Richard E.; Taylor, Charlotte E.

2013-01-01

Urbanisation typically results in a reduction of hollow-bearing trees and an increase in the density of particularly species, potentially resulting in an increased level of competition as cavity-nesting species compete for a limited resource. To improve understanding of hollow usage between urban cavity-nesting species in Australia, particularly parrots, we investigated how the hollow-using assemblage, visitation rate, diversity and number of interactions varied between hollows within urban remnant forest and continuous forest. Motion-activated video cameras were installed, via roped access to the canopy, and hollow usage was monitored at 61 hollows over a two-year period. Tree hollows within urban remnants had a significantly different assemblage of visitors to those in continuous forest as well as a higher rate of visitation than hollows within continuous forest, with the rainbow lorikeet making significantly more visitations than any other taxa. Hollows within urban remnants were characterised by significantly higher usage rates and significantly more aggressive interactions than hollows within continuous forest, with parrots responsible for almost all interactions. Within urban remnants, high rates of hollow visitation and both interspecific and intraspecific interactions observed at tree hollows suggest the number of available optimal hollows may be limiting. Understanding the usage of urban remnant hollows by wildlife, as well as the role of parrots as a potential flagship for the conservation of tree-hollows, is vital to prevent a decrease in the diversity of urban fauna, particularly as other less competitive species risk being outcompeted by abundant native species. PMID:23555657

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

Treesearch

David J. Nowak; Robert E., III Hoehn; Daniel E. Crane; Jack C. Stevens; Jeffrey T. Walton

2007-01-01

An analysis of trees in Philadelphia reveals that this city has about 2.1 million trees with canopies that cover 15.7 percent of the area. The most common tree species are black cherry, crabapple, and tree of heaven. The urban forest currently stores about 530,000 tons of carbon valued at $9.8 million. In addition, these trees remove about 16,100 tons of carbon per...

Mapping urban forest tree species using IKONOS imagery: preliminary results.

PubMed

Pu, Ruiliang

2011-01-01

A stepwise masking system with high-resolution IKONOS imagery was developed to identify and map urban forest tree species/groups in the City of Tampa, Florida, USA. The eight species/groups consist of sand live oak (Quercus geminata), laurel oak (Quercus laurifolia), live oak (Quercus virginiana), magnolia (Magnolia grandiflora), pine (species group), palm (species group), camphor (Cinnamomum camphora), and red maple (Acer rubrum). The system was implemented with soil-adjusted vegetation index (SAVI) threshold, textural information after running a low-pass filter, and brightness threshold of NIR band to separate tree canopies from non-vegetated areas from other vegetation types (e.g., grass/lawn) and to separate the tree canopies into sunlit and shadow areas. A maximum likelihood classifier was used to identify and map forest type and species. After IKONOS imagery was preprocessed, a total of nine spectral features were generated, including four spectral bands, three hue-intensity-saturation indices, one SAVI, and one texture image. The identified and mapped results were examined with independent ground survey data. The experimental results indicate that when classifying all the eight tree species/ groups with the high-resolution IKONOS image data, the identifying accuracy was very low and could not satisfy a practical application level, and when merging the eight species/groups into four major species/groups, the average accuracy is still low (average accuracy = 73%, overall accuracy = 86%, and κ = 0.76 with sunlit test samples). Such a low accuracy of identifying and mapping the urban tree species/groups is attributable to low spatial resolution IKONOS image data relative to tree crown size, to complex and variable background spectrum impact on crown spectra, and to shadow/shaded impact. The preliminary results imply that to improve the tree species identification accuracy and achieve a practical application level in urban area, multi-temporal (multi-seasonal) or hyperspectral data image data should be considered for use in the future.

Trees for Urban Use in Puerto Rico and the Virgin Islands

Treesearch

Thomas H. Schubert

1979-01-01

Describes and illustrates forty-six tree species useful for shade and ornament in Puerto Rico and the Virgin Islands. Information is alsoprovided about planting, maintenance, and appropriate use of trees in urban areas.

Climate ready urban trees for Central Valley cities

Treesearch

E.G. McPherson; A.M. Berry

2015-01-01

Urban forests provide many societal and ecological services to cities and their inhabitants. Many species of trees are under stress due to anthropogenic and natural climate changes. Projected climatic shifts will change temperature, precipitation, and the incidences of pest and disease outbreaks. The tolerance of urban trees to these stressors varies considerably among...

Assessing urban forest effects and values, New York City's urban forest

Treesearch

David J. Nowak; Robert E., III Hoehn; Daniel E. Crane; Jack C. Stevens; Jeffrey T. Walton

2007-01-01

An analysis of trees in New York City reveals that this city has about 5.2 million trees with canopies that cover 20.9 percent of the area. The most common tree species are tree of heaven, black cherry, and sweetgum. The urban forest currently stores about 1.35 million tons of carbon valued at $24.9 million. In addition, these trees remove about 42,300 tons of carbon...

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

Treesearch

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...

The dust retention capacities of urban vegetation-a case study of Guangzhou, South China.

PubMed

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.

Evaluation of four methods for estimating leaf area of isolated trees

Treesearch

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...

Historical vegetation change in Oakland and its implications for urban forest management

Treesearch

David J. Nowak

1993-01-01

The history of Oakland, California's urban forest was researched to determine events that could influence future urban forests. Vegetation in Oakland has changed drastically from a preurbanized area with approximately 2% tree cover to a present tree cover of 19%. Species composition of trees was previously dominated by coast live oak (Quercus agrifolia...

Foliar nitrogen characteristics of four tree species planted in New York City forest restoration sites

Treesearch

Nancy Falxa-Raymond; Matthew I. Palmer; Timon McPhearson; Kevin L. Griffin

2014-01-01

Urban forests provide important environmental benefits, leading many municipal governments to initiate citywide tree plantings. However, nutrient cycling in urban ecosystems is difficult to predict, and nitrogen (N) use in urban trees may be quite different from use in rural forests. To gain insight into these biogeochemical and physiological processes, we compared...

Assessing urban forest effects and values, Minneapolis' urban forest

Treesearch

David J. Nowak; Robert E. III Hoehn; Daniel E. Crane; Jack C. Stevens; Jeffrey T. Walton

2006-01-01

An analysis of trees in Minneapolis, MN, reveals that the city has about 979,000 trees with canopies that cover 26.4 percent of the area. The most common tree species are green ash, American elm, and boxelder. The urban forest currently stores about 250,000 tons of carbon valued at $4.6 million. In addition, these trees remove about 8,900 tons of carbon per year ($164,...

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

Treesearch

David J. Nowak; Robert E., III Hoehn; Daniel E. Crane; Jack C. Stevens; Jeffrey T. Walton

2006-01-01

An analysis of trees in Casper, WY reveals that this city has about 123,000 trees with canopies that cover 8.9 percent of the area. The most common tree species are plains cottonwood, blue spruce, and American elm. The urban forest currently store about 37,000 tons of carbon valued at $689,000. In addition, these trees remove about 1,200 tons of carbon per year ($22,...

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

Treesearch

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...

Assessing urban forest effects and values, San Francisco's urban forest

Treesearch

David J. Nowak; Robert E., III Hoehn; Daniel E. Crane; Jack C. Stevens; Jeffrey T. Walton

2007-01-01

An analysis of trees in San Francisco, CA reveals that this city has about 669,000 trees with canopies that cover 11.9 percent of the area. The most common tree species are blue gum eucalyptus, Monterey pine, and Monterey cypress. The urban forest currently stores about 196,000 tons of carbon valued at $3.6 million. In addition, these trees remove about 5,200 tons of...

Residential Knowledge of Native Tree Species: A Case Study of Residents in Four Southern Ontario Municipalities

NASA Astrophysics Data System (ADS)

Almas, Andrew D.; Conway, Tenley M.

2017-01-01

In the past decade, municipalities across North America have increased investment in their urban forests in an effort to maintain and enhance the numerous benefits provided by them. Some municipalities have now drafted long-term urban forest management plans that emphasize the planting of native trees, to improve ecological integrity, and participation of residents, since the majority of urban trees are typically located on residential property. Yet it is unclear if residents are familiar with native trees or municipalities' urban forest management goals. Through a case study of southern Ontario municipalities, we administered a survey exploring residents' ability to correctly label common tree species as native or non-native, as well as their knowledge of urban forest management plans to test four hypotheses: 1) residents in municipalities with an urban forest management plans will be more knowledgeable about the native status of common street trees; 2) residents who have lived in the area longer will have greater knowledge; 3) knowledge level will be correlated with education level, ethnicity, and income; and 4) residents' knowledge will be related to having planted trees on their property. Our results indicate that residents are better able to identify common native trees than correctly determine which trees are non-native, although knowledge levels are generally low. Knowledge was significantly related to length of residency and tree planting experience, supporting hypotheses 2 and 4. These results highlight the importance of experience and local knowledge acquisition in relation to basic knowledge about urban trees, and also point to the failures of resident outreach within the case study municipalities.

Residential Knowledge of Native Tree Species: A Case Study of Residents in Four Southern Ontario Municipalities.

PubMed

Almas, Andrew D; Conway, Tenley M

2017-01-01

In the past decade, municipalities across North America have increased investment in their urban forests in an effort to maintain and enhance the numerous benefits provided by them. Some municipalities have now drafted long-term urban forest management plans that emphasize the planting of native trees, to improve ecological integrity, and participation of residents, since the majority of urban trees are typically located on residential property. Yet it is unclear if residents are familiar with native trees or municipalities' urban forest management goals. Through a case study of southern Ontario municipalities, we administered a survey exploring residents' ability to correctly label common tree species as native or non-native, as well as their knowledge of urban forest management plans to test four hypotheses: 1) residents in municipalities with an urban forest management plans will be more knowledgeable about the native status of common street trees; 2) residents who have lived in the area longer will have greater knowledge; 3) knowledge level will be correlated with education level, ethnicity, and income; and 4) residents' knowledge will be related to having planted trees on their property. Our results indicate that residents are better able to identify common native trees than correctly determine which trees are non-native, although knowledge levels are generally low. Knowledge was significantly related to length of residency and tree planting experience, supporting hypotheses 2 and 4. These results highlight the importance of experience and local knowledge acquisition in relation to basic knowledge about urban trees, and also point to the failures of resident outreach within the case study municipalities.

Urban tree effects on fine particulate matter and human health

Treesearch

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'...

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

PubMed

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.

Assessing urban forest effects and values, Washington, D.C.'s urban forest

Treesearch

David J. Nowak; Robert E. III Hoehn; Daniel E. Crane; Jack C. Stevens; Jeffrey T. Walton

2006-01-01

An analysis of trees in Washington, D.C. reveals that this city has about 1,928,000 trees with canopies that cover 28.6 percent of the area. The most common tree species are American beech, red maple, and boxelder. The urban forest currently store about 526,000 tons of carbon valued at $9.7 million. In addition, these trees remove about 16,200 tons of carbon per year...

[Species composition and spatial structure of plants in urban parks of Beijing].

PubMed

Zhao, Juan-Juan; Ouyang, Zhi-Yun; Zheng, Hua; Xu, Wei-Hua; Wang, Xiao-Ke

2009-02-01

By the method of stratified random sampling, the species composition and spatial structure of the plants in 53 parks in Beijing urban area were investigated, aimed to provide basic information for the protection of plant diversity in the parks and the management of the parks. A total of 492 plant species belong to 96 families and 283 genera were recorded. Based on the data of 21 investigation items about the trees, shrubs, and grasses in the study area and related statistical analyses, the plant structural patterns commonly seen in the green space of the parks of Beijing urban area were introduced. Among the plants in the parks, native species occupied 53.86% of the total. The chorological composition of the genera embraced broad kinds of geographical elements in China, and the predominance of dominant plants was remarkable. In most green patches of the parks, herbaceous species were more abundant and had higher coverage, shrubs had relatively low coverage and were less beneath tree canopy, and trees and shrubs had lower species richness and density. The canopy breadth and the diameter of breast height of trees as well as the breadth of shrubs and the heights of trees and shrubs were basically at the second grade, but the canopy structure of the trees were better, with good conditions of sunlight and growth. The crown missing of the shrubs was relatively low. It was suggested from correlation analyses and document survey of Beijing parks construction history that park landscape design, alien species introduction; and cultivation management were the main factors affecting the species composition and spatial structure of the plants in Beijing urban parks.

Rainfall interception by Santa Monica’s municipal urban forest

Treesearch

Q. Xiao; E.G. McPherson

2004-01-01

Tree health is a critical parameter for evaluating urban ecosystem health and sustainability. Tradi­tionally, this parameter has been derived from field surveys. We used multispectral remote sensing data and GIS techniques to determine tree health at the University of California, Davis. The study area (363 ha) contained 8,962 trees of 215 species. Tree health...

Houston’s Urban Forest, 2015

Treesearch

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...

The figs of winter: Seasonal importance of fruiting fig trees (Ficus: Moraceae) for urban birds

NASA Astrophysics Data System (ADS)

Walther, Bruno A.; Geier, Jessica; Chou, Lien-Siang; Bain, Anthony

2018-07-01

Birds and figs are conspicuous members of the tropical and subtropical ecosystems. Because they are easily observed and very speciose, their relationships have been well studied in many areas, and the figs are considered a keystone resource for many bird species which are efficient fig seed dispersers. Taiwan has a relatively high endemism rate for many taxa (17% of bird species) but because of its high human population density, most lowland habitats are heavily developed, of which much of it covered by dense urban habitation. To establish the importance of urban figs for birds, we focused our surveys mostly on three common urban fig species (Ficus caulocarpa, F. microcarpa and F. subpisocarpa). We observed trees with ripening figs from July 2013 to December 2016 in order to determine the composition of the fig-consuming bird community. In addition, we added all the information available in the scientific literature and birdwatchers' observations which we could find. In total, we observed 42 bird species consuming 18 fig species. The bird diversity in urban areas was non-negligible even during winter. Therefore, there are two reasons why figs are important for Taiwan's bird avifauna: in cities, the tree diversity is generally low so that figs provide a stable food resource; and since figs are fruiting all year-round, they are one of the few reliable resources available during winter when many migrant birds overwinter in Taiwan. Already crucial for many species in tropical and subtropical forests, fig trees may also be essential for urban birds in tropical and subtropical regions.

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

NASA Astrophysics Data System (ADS)

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.

Evaluation of a portable MOS electronic nose to detect root rots in shade tree species

Treesearch

Manuela Baietto; Letizia Pozzi; Alphus Dan Wilson; Daniele Bassi

2013-01-01

The early detection of wood decays in high-value standing trees is very important in urban areas because mitigating control measures must be implemented long before tree failures result in property damage or injuries to citizens. Adverse urban environments increase physiological stresses in trees, causing greater susceptibility to attacks by pathogenic decay fungi. The...

The urban forests of Philadelphia

Treesearch

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...

Austin's Urban Forest, 2014

Treesearch

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...

Assessing urban forest effects and values, Los Angeles' urban forest

Treesearch

David J. Nowak; Robert E. III Hoehn; Daniel E. Crane; Lorraine Weller; Antonio Davila

2011-01-01

An analysis of trees in Los Angeles, CA, reveals that this area has about 6 million trees with tree and shrub canopies that cover 24.9 percent of the city. The most common tree species are Italian cypress, scrub oak, laurel sumac, Mexican fan palm, and Indian laurel, Trees in Los Angeles currently store about 1.3 million tons of carbon (4.7 million tons CO2...

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

NASA Astrophysics Data System (ADS)

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.

A ground-based method of assessing urban forest structure and ecosystem services

Treesearch

David J. Nowak; Daniel E. Crane; Jack C. Stevens; Robert E. Hoehn; Jeffrey T. Walton; Jerry Bond

2008-01-01

To properly manage urban forests, it is essential to have data on this important resource. An efficient means to obtain this information is to randomly sample urban areas. To help assess the urban forest structure (e.g., number of trees, species composition, tree sizes, health) and several functions (e.g., air pollution removal, carbon storage and sequestration), the...

Assessing allergenicity in urban parks: A nature-based solution to reduce the impact on public health.

PubMed

Cariñanos, Paloma; Casares-Porcel, Manuel; Díaz de la Guardia, Consuelo; Aira, María Jesús; Belmonte, Jordina; Boi, Marzia; Elvira-Rendueles, Belén; De Linares, Concepción; Fernández-Rodriguez, Santiago; Maya-Manzano, José María; Pérez-Badía, Rosa; Rodriguez-de la Cruz, David; Rodríguez-Rajo, Francisco Javier; Rojo-Úbeda, Jesús; Romero-Zarco, Carlos; Sánchez-Reyes, Estefanía; Sánchez-Sánchez, José; Tormo-Molina, Rafael; Vega Maray, Ana Mª

2017-05-01

Urban parks play a key role in the provision of ecosystem services, actively participating in improving the quality of life and welfare of local residents. This paper reports on the application of an index designed to quantify the allergenicity of urban parks in a number of Spanish cities. The index, which records biological and biometric parameters for the tree species growing there, classifies parks in terms of the risk they pose for allergy sufferers, graded as null, low, moderate or high. In this initial phase, the index was applied to 26 green areas in 24 Spanish cities; green areas varied in type (urban park, historical or modern garden, boulevard, square or urban forest), size 1-100 ha), geographical location, species richness, number of trees and tree density (number of trees / ha.). The data obtained were used to calculate the percentage of allergenic species in each park, which varied between 17-67%; density ranged from 100 to 300 trees/ha. The index values recorded ranged from a minimum of .07 to a maximum of .87; a significant correlation was found between index value and both number of trees and tree density. Taking an index value of .30 as the threshold considered sufficient to trigger allergy symptoms in the sensitive population, 12 of the parks studied may be regarded as unhealthy at any time of the year. Corrective measures to mitigate the impact of pollen emissions include the implementation of nature-based solutions at various levels: planning and design, handling and management, and strengthening of urban green-infrastructure elements. The index proved to be a useful tool for environmental analysis, and complies with the principles of portability and scalability central to current and horizon scientific research. Copyright © 2017 Elsevier Inc. All rights reserved.

Urban tree effects on soil organic carbon.

PubMed

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

2014-01-01

Urban trees sequester carbon into biomass and provide many ecosystem service benefits aboveground leading to worldwide tree planting schemes. Since soils hold ∼75% of ecosystem organic carbon, understanding the effect of urban trees on soil organic carbon (SOC) and soil properties that underpin belowground ecosystem services is vital. We use an observational study to investigate effects of three important tree genera and mixed-species woodlands on soil properties (to 1 m depth) compared to adjacent urban grasslands. Aboveground biomass and belowground ecosystem service provision by urban trees are found not to be directly coupled. Indeed, SOC enhancement relative to urban grasslands is genus-specific being highest under Fraxinus excelsior and Acer spp., but similar to grasslands under Quercus robur and mixed woodland. Tree cover type does not influence soil bulk density or C∶N ratio, properties which indicate the ability of soils to provide regulating ecosystem services such as nutrient cycling and flood mitigation. The trends observed in this study suggest that genus selection is important to maximise long-term SOC storage under urban trees, but emerging threats from genus-specific pathogens must also be considered.

Urban Tree Effects on Soil Organic Carbon

PubMed Central

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

2014-01-01

Urban trees sequester carbon into biomass and provide many ecosystem service benefits aboveground leading to worldwide tree planting schemes. Since soils hold ∼75% of ecosystem organic carbon, understanding the effect of urban trees on soil organic carbon (SOC) and soil properties that underpin belowground ecosystem services is vital. We use an observational study to investigate effects of three important tree genera and mixed-species woodlands on soil properties (to 1 m depth) compared to adjacent urban grasslands. Aboveground biomass and belowground ecosystem service provision by urban trees are found not to be directly coupled. Indeed, SOC enhancement relative to urban grasslands is genus-specific being highest under Fraxinus excelsior and Acer spp., but similar to grasslands under Quercus robur and mixed woodland. Tree cover type does not influence soil bulk density or C∶N ratio, properties which indicate the ability of soils to provide regulating ecosystem services such as nutrient cycling and flood mitigation. The trends observed in this study suggest that genus selection is important to maximise long-term SOC storage under urban trees, but emerging threats from genus-specific pathogens must also be considered. PMID:25003872

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

PubMed

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.

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

Treesearch

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...

Effects of a Major Tree Invader on Urban Woodland Arthropods.

PubMed

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.

Effects of a Major Tree Invader on Urban Woodland Arthropods

PubMed Central

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

Biotechnological efforts for preserving and enhancing temperate hardwood tree biodiversity, health, and productivity

Treesearch

Paula M. Pijut; Shaneka S. Lawson; Charles H. Michler

2011-01-01

Hardwood tree species in forest, plantation, and urban environments (temperate regions of the world) are important biological resources that play a significant role in the economy and the ecology of terrestrial ecosystems, and they have aesthetic and spiritual value. Because of these many values of hardwood tree species, preserving forest tree biodiversity through the...

The effects of urban warming on herbivore abundance and street tree condition.

PubMed

Dale, Adam G; Frank, Steven D

2014-01-01

Trees are essential to urban habitats because they provide services that benefit the environment and improve human health. Unfortunately, urban trees often have more herbivorous insect pests than rural trees but the mechanisms and consequences of these infestations are not well documented. Here, we examine how temperature affects the abundance of a scale insect, Melanaspis tenebricosa (Comstock) (Hemiptera: Diaspididae), on one of the most commonly planted street trees in the eastern U.S. Next, we examine how both pest abundance and temperature are associated with water stress, growth, and condition of 26 urban street trees. Although trees in the warmest urban sites grew the most, they were more water stressed and in worse condition than trees in cooler sites. Our analyses indicate that visible declines in tree condition were best explained by scale-insect infestation rather than temperature. To test the broader relevance of these results, we extend our analysis to a database of more than 2700 Raleigh, US street trees. Plotting these trees on a Landsat thermal image of Raleigh, we found that warmer sites had over 70% more trees in poor condition than those in cooler sites. Our results support previous studies linking warmer urban habitats to greater pest abundance and extend this association to show its effect on street tree condition. Our results suggest that street tree condition and ecosystem services may decline as urban expansion and global warming exacerbate the urban heat island effect. Although our non-probability sampling method limits our scope of inference, our results present a gloomy outlook for urban forests and emphasize the need for management tools. Existing urban tree inventories and thermal maps could be used to identify species that would be most suitable for urban conditions.

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

NASA Astrophysics Data System (ADS)

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 (< 0.5 meter) of two tree species with contrasting canopy and bark structure (Fagus grandifolia, vs. Liriodendron tulipifera), and evaluated for soil microbial structure via metagenomic analysis and soil C/N content. We hypothesize that soil moisture constraints coupled with increases in recalcitrant C will decrease gram negative bacteria (i.e., dependent on labile C) while increasing saprophytic fungal community abundance (i.e., specialist consuming recalcitrant C) within both surface and subsurface soils experiencing the greatest urban pressure (i.e., forest edge). We further expect trees located on the edge of forest fragments will maintain greater surface soil (< 20 cm) C concentrations due to decreased soil moisture constraining microbial activity (e.g., slower decay), and increased capture of recalcitrant C stocks from industrial/vehicle emission sources (e.g., black C). Our initial results support our hypotheses that 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.

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

PubMed

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.

The morphological structure of leaves and the dust-retaining capability of afforested plants in urban Guangzhou, South China.

PubMed

Liu, Lu; Guan, Dongsheng; Peart, M R

2012-09-01

Air pollution is a serious health problem throughout the world, exacerbating a wide range of respiratory and vascular illnesses in urban areas. The mass artificial plantation is very helpful to absorb dust and reduce pollution for conservation of the urban environment. The foliar surface of plants is an important receptor of atmospheric pollutants. Therefore, selection of suitable plant species for urban environment is very important. The dust-retaining capability of urban trees in Guangzhou was determined at four different types of urban area, and the morphological traits of their leaves such as wax, cuticle, stomata, and trichomes were observed under a scanning electron microscope. It was determined that the dust-retaining capability of any given tree species is significantly different in the same place. Of the four studied tree species in the industrial area (IA) and commercial/traffic areas (CTA) type urban areas, the highest amounts of dust removed by Mangifera indica Linn was 12.723 and 1.482 g/m(2), respectively. However, in contrast, the equivalent maxima for Bauhinia blakeana is only 2.682 g/m(2) and 0.720 g/m(2), respectively. Different plant species have different leaf morphology. The leaf of M. indica has deep grooves and high stomata density which are in favor of dust-retained, and thus, their dust-retained capability is stronger, while B. blakeana has the cells and epicuticular wax with its stomata arranging regularly, resulting in poor dust catching capability. Leaf size was also shown to be related to dust capture for the four studied tree species. The dust removal capacity of individual tree species should be taken into account in the management of greening plantation in and around an urban area. It was also shown that temporal variation in dust accumulation occurred over the 28-day observation period and this was discussed. Furthermore, spatial contrasts in dust accumulation were evidenced by the data. This reflected the differing pollution loadings of the four urban-type areas. The highest amount of dust accumulation was associated with the industrial area in which shipyard and steelworks occurred whilst the lowest dust accumulation was associated with the grounds of the University which was the control area.

The tree BVOC index

Treesearch

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...

Allometric equations for urban ash trees (Fraxinus spp.) in Oakville, Southern Ontario, Canada

Treesearch

Paula J. Peper; Claudia P. Alzate; John W. McNeil; Jalil Hashemi

2014-01-01

Tree growth equations are an important and common tool used to effectively assess the yield and determine management practices in forest plantations. Increasingly, they are being developed for urban forests, providing tools to assist urban forest managers with species selection, placement, and estimation of management costs and ecosystem services. This study describes...

Vegetation in Bangalore's Slums: Composition, Species Distribution, Density, Diversity, and History

NASA Astrophysics Data System (ADS)

Gopal, Divya; Nagendra, Harini; Manthey, Michael

2015-06-01

There is widespread acknowledgement of the need for biodiversity and greening to be part of urban sustainability efforts. Yet we know little about greenery in the context of urban poverty, particularly in slums, which constitute a significant challenge for inclusive development in many rapidly growing cities. We assessed the composition, density, diversity, and species distribution of vegetation in 44 slums of Bangalore, India, comparing these to published studies on vegetation diversity in other land-use categories. Most trees were native to the region, as compared to other land-use categories such as parks and streets which are dominated by introduced species. Of the most frequently encountered tree species, Moringa oleifera and Cocos nucifera are important for food, while Ficus religiosa plays a critical cultural and religious role. Tree density and diversity were much lower in slums compared to richer residential neighborhoods. There are also differences in species preferences, with most plant (herb, shrub and vines) species in slums having economic, food, medicinal, or cultural use, while the species planted in richer residential areas are largely ornamental. Historic development has had an impact on species distribution, with older slums having larger sized tree species, while recent slums were dominated by smaller sized tree species with greater economic and food use. Extensive focus on planting trees and plant species with utility value is required in these congested neighborhoods, to provide livelihood support.

Biological and environmental controls on tree transpiration in a suburban landscape

NASA Astrophysics Data System (ADS)

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.

Urbanization Level and Woodland Size Are Major Drivers of Woodpecker Species Richness and Abundance

PubMed Central

Myczko, Łukasz; Rosin, Zuzanna M.; Skórka, Piotr; Tryjanowski, Piotr

2014-01-01

Urbanization is a process globally responsible for loss of biodiversity and for biological homogenization. Urbanization may have a direct negative impact on species behaviour and indirect effects on species populations through alterations of their habitats, for example patch size and habitat quality. Woodpeckers are species potentially susceptible to urbanization. These birds are mostly forest specialists and the development of urban areas in former forests may be an important factor influencing their richness and abundance, but documented examples are rare. In this study we investigated how woodpeckers responded to changes in forest habitats as a consequence of urbanization, namely size and isolation of habitat patches, and other within-patch characteristics. We selected 42 woodland patches in a gradient from a semi-natural rural landscape to the city centre of Poznań (Western Poland) in spring 2010. Both species richness and abundance of woodpeckers correlated positively to woodland patch area and negatively to increasing urbanization. Abundance of woodpeckers was also positively correlated with shrub cover and percentage of deciduous tree species. Furthermore, species richness and abundance of woodpeckers were highest at moderate values of canopy openness. Ordination analyses confirmed that urbanization level and woodland patch area were variables contributing most to species abundance in the woodpecker community. Similar results were obtained in presence-absence models for particular species. Thus, to sustain woodpecker species within cities it is important to keep woodland patches large, multi-layered and rich in deciduous tree species. PMID:24740155

Urbanization level and woodland size are major drivers of woodpecker species richness and abundance.

PubMed

Myczko, Lukasz; Rosin, Zuzanna M; Skórka, Piotr; Tryjanowski, Piotr

2014-01-01

Urbanization is a process globally responsible for loss of biodiversity and for biological homogenization. Urbanization may have a direct negative impact on species behaviour and indirect effects on species populations through alterations of their habitats, for example patch size and habitat quality. Woodpeckers are species potentially susceptible to urbanization. These birds are mostly forest specialists and the development of urban areas in former forests may be an important factor influencing their richness and abundance, but documented examples are rare. In this study we investigated how woodpeckers responded to changes in forest habitats as a consequence of urbanization, namely size and isolation of habitat patches, and other within-patch characteristics. We selected 42 woodland patches in a gradient from a semi-natural rural landscape to the city centre of Poznań (Western Poland) in spring 2010. Both species richness and abundance of woodpeckers correlated positively to woodland patch area and negatively to increasing urbanization. Abundance of woodpeckers was also positively correlated with shrub cover and percentage of deciduous tree species. Furthermore, species richness and abundance of woodpeckers were highest at moderate values of canopy openness. Ordination analyses confirmed that urbanization level and woodland patch area were variables contributing most to species abundance in the woodpecker community. Similar results were obtained in presence-absence models for particular species. Thus, to sustain woodpecker species within cities it is important to keep woodland patches large, multi-layered and rich in deciduous tree species.

Woody invasions of urban trails and the changing face of urban forests in the great plains, USA

USGS Publications Warehouse

Nemec, K.T.; Allen, Craig R.; Alai, A.; Clements, G.; Kessler, A.C.; Kinsell, T.; Major, A.; Stephen, B.J.

2011-01-01

Corridors such as roads and trails can facilitate invasions by non-native plant species. The open, disturbed habitat associated with corridors provides favorable growing conditions for many non-native plant species. Bike trails are a corridor system common to many urban areas that have not been studied for their potential role in plant invasions. We sampled five linear segments of urban forest along bike trails in Lincoln, Nebraska to assess the invasion of woody non-native species relative to corridors and to assess the composition of these urban forests. The most abundant plant species were generally native species, but five non-native species were also present: white mulberry (Morus alba), common buckthorn (Rhamnus cathartica), tree-of-heaven (Ailanthus altissima), honeysuckle (Lonicera spp.) and elm (Ulmus spp.). The distribution of two of the woody species sampled, common buckthorn and honeysuckle, significantly decreased with increasing distance from a source patch of vegetation (P = 0.031 and 0.030). These linear habitats are being invaded by non-native tree and shrub species, which may change the structure of these urban forest corridors. If non-native woody plant species become abundant in the future, they may homogenize the plant community and reduce native biodiversity in these areas. ?? 2011 American Midland Naturalist.

Assessing urban forest effects and values: Morgantown's Urban Forest

Treesearch

David J. Nowak; Robert E. III Hoehn; Daniel E. Crane; Jack C. Stevens; Jonathan Cumming; Sandhya Mohen; Anne Buckelew. Cumming

2012-01-01

An analysis of the community forest in Morgantown, WV, was undertaken in 2004 to characterize the structural and functional attributes of this forest resource. The assessment revealed that this city has about 658,000 trees with canopies that cover 35.5 percent of the area. The most common tree species are sugar maple, black cherry, and hawthorn. The urban forest...

[Adsorption Capacity of the Air Particulate Matter in Urban Landscape Plants in Different Polluted Regions of Beijing].

PubMed

Zhang, Wei-kang; Wang, Bing; Niu, Xiang

2015-07-01

Urban landscape plants, as one of the important factors of the urban ecosystem, play an important role in stagnating airborne particulates and purifying urban atmospheric environment. In this article, six kinds of common garden plants were studied, and aerosol generator (QRJZFSQ-I) was used to measure the ability of their leaves to stagnate atmospheric particulates (TSP and PM2.5) in different polluted regions. Meanwhile, environmental scanning electron microscope was used to observe changes in the leaf structure of the tested tree species. The results showed: (1)Among the tested tree species, the ability of coniferous species to stagnate atmospheric particulates was higher than that of broad-leaved species per unit leaf area. Pinus tabuliformis stagnated the highest volume of (3. 89± 0. 026) µg . m-2, followed by Pinus bungeana of (2. 82 ± 0. 392) µg . cm-2, and Populus tomentosa stagnated the minimum of (2. 00 ± 0. 118) µg . cm-2; (2) Through observing the leaf microstructure morphology, coniferous species were found to have tightly packed stomas, stoma density and surface roughness higher than those of broad-leaved species, and they could also secrete oil; (3) In different polluted regions, the leaves of the same tree species showed significant difference in stagnating TSP. Per unit leaf area, the tree species leaves situated around the 5th Ring Road had higher ability to absorb TSP than the tree species leaves at Botanical Garden, while their abilities to absorb PM2.5 showed no significant difference; (4) In different polluted regions, significantly adaptive changes were found in leaf structure. Comparing to the region with light pollution, the outer epidermal cells of the plant leaves in region with heavy pollution shrank, and the roughness of the leaf skin textures as well as the stomatal frequency and villous length increased. In spite of the significant changes in plant leaves exposed to the heavy pollution, these plants could still maintain normal and healthy growth.

Producing edible landscapes in Seattle's urban forest

Treesearch

Rebecca McLain; Melissa Poe; Patrick T. Hurley; Joyce Lecompte-Mastenbrook; Marla R. Emery

2012-01-01

Over the next decades, green infrastructure initiatives such as tree planting campaigns, and ecological restoration will dramatically change the species composition, species distribution and structure of urban forests across the United States. These impending changes are accompanied by a demand for urban public spaces where people can engage in practices such as...

The role of composition, invasives, and maintenance emissions on urban forest carbon stocks.

PubMed

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.

The Role of Composition, Invasives, and Maintenance Emissions on Urban Forest Carbon Stocks

NASA Astrophysics Data System (ADS)

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.

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

PubMed Central

Sinu, Palatty Allesh

2017-01-01

Abstract 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. PMID:29492020

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

PubMed

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.

Evapotranspiration of the urban forest at the municipal scale in Los Angeles, CA

NASA Astrophysics Data System (ADS)

Litvak, E.; Pataki, D. E.

2015-12-01

The severest drought on record in southern California and predictions of continued water shortages make it essential to understand urban water use. However, urban evapotranspiration (ET), which is an important part of municipal water budgets, remains a major uncertainty. Urban ET is difficult to measure and model, particularly in cities with diverse plant composition. The city of Los Angeles contains more than 6 million trees, most of which are non-natives that originate from multiple geographic regions, which further complicates predictions of urban forest transpiration. Previously, we made extensive in situ measurements of tree transpiration and turfgrass ET in greater Los Angeles area. Here, we utilize these data to systematize transpiration of different tree species based on physiological mechanisms underlying plant water relations. The resulting empirical model estimates Los Angeles urban forest ET from easy-to-collect plant characteristics and freely available environmental parameters. Plant characteristics are tree diameter, wood type (e.g. coniferous), phenological type (e.g. evergreen) and plant composition. Environmental parameters are vapor pressure deficit of the air, incoming solar radiation and reference ET (all available at http://cimis.water.ca.gov). By combining this model with existing surveys of urban trees in Los Angeles, we estimated that citywide ET of irrigated landscapes varies from 1.2 ± 0.5 mm/d in winter to 2.8 ± 1.1 mm/d in summer. On average, trees and turfgrass contributed 27% and 73% to total tree+turfgrass ET, correspondingly. To our knowledge, this model provides the first citywide estimates of Los Angeles ET differentiated by wood types and plant composition. These results will inform decision makers about species-specific water use by urban trees and assist with determining landscape designs that are beneficial for water conservation. This model may also be incorporated into a regional hydrologic model to provide spatially resolved ET at the municipal scale.

Tree holes as larval habitats for Aedes aegypti in urban, suburban and forest habitats in a dengue affected area.

PubMed

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

2015-12-01

Aedes aegypti (L.) (Diptera: Culicidae), the main vector of dengue and urban yellow fever in the world, is highly adapted to the human environment. Artificial containers are the most common larval habitat for the species, but it may develop in tree holes and other phytotelmata. This study assessed whether tree holes in San Ramón de la Nueva Orán, a city located in subtropical montane moist forest where dengue outbreaks occur, are relevant as larval habitat for Ae. aegypti and if the species may be found in natural areas far from human habitations. Water holding tree holes were sampled during 3 years once a month along the rainy season using a siphon bottle, in urban and suburban sites within the city and in adjacent forested areas. Larvae and pupae were collected and the presence and volume of water in each tree hole were recorded. Finding Ae. aegypti in forested areas was an isolated event; however, the species was frequently collected from tree holes throughout the city and along the sampling period. Moreover, larvae were collected in considerably high numbers, stressing the importance of taking into account these natural cavities as potential reinfestation foci within dengue control framework.

A new approach to quantify and map carbon stored, sequestered and emissions avoided by urban forests

Treesearch

E. Gregory McPherson; Qingfu Xiao; Elena Aguaron

2013-01-01

This paper describes the use of field surveys, biometric information for urban tree species and remote sensing to quantify and map carbon (C) storage, sequestration and avoided emissions from energy savings. Its primary contribution is methodological; the derivation and application of urban tree canopy (UTC) based transfer functions (t C ha-1 UTC). Findings for Los...

Breeding trees resistant to insects and diseases: putting theory into application

Treesearch

Richard A. Sniezko; Jennifer Koch

2017-01-01

Tree species world-wide are under increasing threat from diseases and insects, many of which are non-native. The integrity of our natural, urban and plantation forest ecosystems, and the services they provide are seriously imperiled. Breeding programs that harness the natural genetic resistance within tree species can provide a durable solution to these threats. In...

Inter- and intraannual growth patterns of urban small-leaved lime (Tilia cordata mill.) at two public squares with contrasting microclimatic conditions.

PubMed

Moser, Astrid; Rahman, Mohammad A; Pretzsch, Hans; Pauleit, Stephan; Rötzer, Thomas

2017-06-01

The effects of urban conditions on tree growth have been investigated in an increasing number of studies over the last decades, emphasizing the harsh environment of cities. Urban trees often grow in highly paved, compacted sites with consequently less soil moisture, higher soil temperatures, and greater vapor pressure deficits. However, there is still a knowledge gap regarding the impact of harsh paved environments on urban tree growth during drought years on the growth patterns of urban trees. The present study investigated the structure and growth of the common urban tree species small-leaved lime (Tilia cordata) at a highly paved public square (CPS) compared with a contrasting more open, greener square (OGS). Continuously, measured high precision dendrometer data along with meteorological data of the extreme dry and warm summer 2015 as well as dendrochronological data of the sampled trees were investigated to analyze tree growth during a drought year. The results highlight different tree dimensions and growth patterns of the trees at both sites, influenced by tree age and distinct site conditions. While the trees at OGS grew up to 2.5 mm from July until mid of August, the trees at CPS had only 0.4-mm diameter increment. After the initial expansion at CPS, tree diameter contracted again during summer to the point of shrinkage (up to 0.8 mm) at the end of our investigation. Further drought year analysis confirmed the patterns of significant stem growth reductions in the consecutive two years following the drought. A correlation analysis revealed that transpiration, air temperature, and vapor pressure deficit were negatively correlated with the daily diameter growth, whereas precipitation had a strong positive effect. Due to high transpiration rates associated with anisohydric water use behavior, T. cordata was able to provide evaporative cooling even during drought. However, this anisohydric behavior resulted in substantial growth decline afterwards especially at paved sites like CPS. Our results suggest selection of tree species, such as those with isohydric water use behavior, which may achieve a better balance between growth, transpiration, and hence evaporative cooling.

Subterranean termites in urban forestry: tree preference and management.

PubMed

Zorzenon, F J; Campos, A E C

2015-04-01

Urban tree deterioration is a common problem all over the world. Inappropriate plant species choice and inadequate planting may lead to micro and macro organism attacks, such as pests and diseases. Subterranean termite damage is common and may promote tree falls. In order to help urban forestry planning, this work was carried out for 9 years on 1477 street trees in a neighborhood in the city of São Paulo, Brazil. Plants were identified to species, grouped as native, exotic plants, and palm trees, and their measures of circumference at breast height (CBH) were taken, in order to evaluate if subterranean termite damages are related to tree size and plant group. Four subterranean termite species were identified infesting up to 27% of the plants, with Coptotermes gestroi (Wasmann) being the most common. Palm trees were not damaged by subterranean termites, while native plants are the most susceptible, especially Caesalpinia pluviosa var. peltophoroides (Fabaceae). Among the native plants monitored C. pluviosa var. peltophoroides, Caesalpinia ferrea var. leiostachya, Erythrina speciosa, Piptadenia gonoacantha (Fabaceae), Gochnatia polymorpha (Asteraceae), Tibouchina granulosa (Melastomataceae), and Handroanthus spp. (Bignoniaceae), the latter was the least damaged. Exotic plants were also susceptible with the exception of Lagerstroemia indica (Lythraceae) and Platanus acerifolia (Platanaceae). Correlation analysis showed that the higher the CBH value, the higher the percentage of internal damage by C. gestroi. Infested trees were treated with imidacloprid and thiamethoxam, and subterranean termites were effectively controlled during the 9-year study.

Emerald ash borer and the urban forest: Changes in landslide potential due to canopy loss scenarios in the City of Pittsburgh, PA.

PubMed

Pfeil-McCullough, Erin; Bain, Daniel J; Bergman, Jeffery; Crumrine, Danielle

2015-12-01

Emerald ash borer is expected to kill thousands of ash trees in the eastern U.S. This research develops tools to predict the effect of ash tree loss from the urban canopy on landslide susceptibility in Pittsburgh, PA. A spatial model was built using the SINMAP (Stability INdex MAPping) model coupled with spatially explicit scenarios of tree loss (0%, 25%, 50%, and 75% loss of ash trees from the canopy). Ash spatial distributions were estimated via Monte Carlo methods and available vegetation plot data. Ash trees are most prevalent on steeper slopes, likely due to urban development patterns. Therefore, ash loss disproportionately increases hillslope instability. A 75% loss of ash resulted in roughly 800 new potential landslide initiation locations. Sensitivity testing reveals that variations in rainfall rates, and friction angles produce minor changes to model results relative to the magnitude of parameter variation, but reveal high model sensitivity to soil density and root cohesion values. The model predictions demonstrate the importance of large canopy species to urban hillslope stability, particularly on steep slopes and in areas where soils tend to retain water. To improve instability predictions, better characterization of urban soils, particularly spatial patterns of compaction and species specific root cohesion is necessary. The modeling framework developed in this research will enhance assessment of changes in landslide risk due to tree mortality, improving our ability to design economically and ecologically sustainable urban systems. Copyright © 2015 Elsevier B.V. All rights reserved.

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

PubMed

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.

Assessment of urban tree growth from structure, nutrients and composition data derived from airborne lidar and imaging spectroscopy

NASA Astrophysics Data System (ADS)

Gu, H.; Townsend, P. A.; Singh, A.

2014-12-01

Urban forests provide important ecosystem services related to climate, nutrients, runoff and aesthetics. Assessment of variations in urban forest growth is critical to urban management and planning, as well as to identify responses to climate and other environmental changes. We estimated annual relative basal area increment by tree rings from 37 plots in Madison, Wisconsin and neighboring municipalities. We related relative basal area growth to variables of vegetation traits derived from remote sensing, including structure (aboveground biomass, diameter, height, basal area, crown width and crown length) from discrete-return airborne lidar, and biochemical variables (foliar nitrogen, carbon, lignin, cellulose, fiber and LMA), spectral indices (NDVI, NDWI, PRI, NDII etc.) and species composition from AVIRIS hyperspectral imagery. Variations in tree growth was mainly correlated with tree species composition (R2 = 0.29, RMSE = 0.004) with coniferous stands having a faster growth rate than broadleaf plots. Inclusion of stand basal area improved model prediction from R2 = 0.29 to 0.35, with RMSE = 0.003. Then, we assessed the growth by functional type, we found that foliar lignin concentration and the proportion of live coniferous trees explained 57% variance in the growth of conifer stands. In contrast, broadleaf forest growth was more strongly correlated with species composition and foliar carbon (R2 = 0.59, RMSE = 0.003). Finally, we compared the relative basal area growth by species. In our study area, red pine and white pine exhibited higher growth rates than other species, while white oak plots grew slowest. There is a significant negative relationship between tree height and the relative growth in red pine stands (r = -0.95), as well as a strong negative relationship between crown width and the relative growth in white pine stands (r = -0.87). Growth declines as trees grow taller and wider may partly be the result of reduced photosynthesis and water availability. We also found that canopy cellulose content was negatively correlated with growth in white oak (r = -0.59), which could be caused by trade off of carbon allocation from shoot storage to leaves. These results demonstrate the potential of lidar and hyperspectral imagery to characterize important traits associated with biomass accumulation in urban forests.

Habitat Composition and Connectivity Predicts Bat Presence and Activity at Foraging Sites in a Large UK Conurbation

PubMed Central

Hale, James D.; Fairbrass, Alison J.; Matthews, Tom J.; Sadler, Jon P.

2012-01-01

Background Urbanization is characterized by high levels of sealed land-cover, and small, geometrically complex, fragmented land-use patches. The extent and density of urbanized land-use is increasing, with implications for habitat quality, connectivity and city ecology. Little is known about densification thresholds for urban ecosystem function, and the response of mammals, nocturnal and cryptic taxa are poorly studied in this respect. Bats (Chiroptera) are sensitive to changing urban form at a species, guild and community level, so are ideal model organisms for analyses of this nature. Methodology/Principal Findings We surveyed bats around urban ponds in the West Midlands conurbation, United Kingdom (UK). Sites were stratified between five urban land classes, representing a gradient of built land-cover at the 1 km2 scale. Models for bat presence and activity were developed using land-cover and land-use data from multiple radii around each pond. Structural connectivity of tree networks was used as an indicator of the functional connectivity between habitats. All species were sensitive to measures of urban density. Some were also sensitive to landscape composition and structural connectivity at different spatial scales. These results represent new findings for an urban area. The activity of Pipistrellus pipistrellus (Schreber 1774) exhibited a non-linear relationship with the area of built land-cover, being much reduced beyond the threshold of ∼60% built surface. The presence of tree networks appears to mitigate the negative effects of urbanization for this species. Conclusions/Significance Our results suggest that increasing urban density negatively impacts the study species. This has implications for infill development policy, built density targets and the compact city debate. Bats were also sensitive to the composition and structure of the urban form at a range of spatial scales, with implications for land-use planning and management. Protecting and establishing tree networks may improve the resilience of some bat populations to urban densification. PMID:22428015

Habitat composition and connectivity predicts bat presence and activity at foraging sites in a large UK conurbation.

PubMed

Hale, James D; Fairbrass, Alison J; Matthews, Tom J; Sadler, Jon P

2012-01-01

Urbanization is characterized by high levels of sealed land-cover, and small, geometrically complex, fragmented land-use patches. The extent and density of urbanized land-use is increasing, with implications for habitat quality, connectivity and city ecology. Little is known about densification thresholds for urban ecosystem function, and the response of mammals, nocturnal and cryptic taxa are poorly studied in this respect. Bats (Chiroptera) are sensitive to changing urban form at a species, guild and community level, so are ideal model organisms for analyses of this nature. We surveyed bats around urban ponds in the West Midlands conurbation, United Kingdom (UK). Sites were stratified between five urban land classes, representing a gradient of built land-cover at the 1 km(2) scale. Models for bat presence and activity were developed using land-cover and land-use data from multiple radii around each pond. Structural connectivity of tree networks was used as an indicator of the functional connectivity between habitats. All species were sensitive to measures of urban density. Some were also sensitive to landscape composition and structural connectivity at different spatial scales. These results represent new findings for an urban area. The activity of Pipistrellus pipistrellus (Schreber 1774) exhibited a non-linear relationship with the area of built land-cover, being much reduced beyond the threshold of ∼60% built surface. The presence of tree networks appears to mitigate the negative effects of urbanization for this species. Our results suggest that increasing urban density negatively impacts the study species. This has implications for infill development policy, built density targets and the compact city debate. Bats were also sensitive to the composition and structure of the urban form at a range of spatial scales, with implications for land-use planning and management. Protecting and establishing tree networks may improve the resilience of some bat populations to urban densification.

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

PubMed

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 Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Using urban forest assessment tools to model bird habitat potential

USGS Publications Warehouse

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.

From Google Maps to a fine-grained catalog of street trees

NASA Astrophysics Data System (ADS)

Branson, Steve; Wegner, Jan Dirk; Hall, David; Lang, Nico; Schindler, Konrad; Perona, Pietro

2018-01-01

Up-to-date catalogs of the urban tree population are of importance for municipalities to monitor and improve quality of life in cities. Despite much research on automation of tree mapping, mainly relying on dedicated airborne LiDAR or hyperspectral campaigns, tree detection and species recognition is still mostly done manually in practice. We present a fully automated tree detection and species recognition pipeline that can process thousands of trees within a few hours using publicly available aerial and street view images of Google MapsTM. These data provide rich information from different viewpoints and at different scales from global tree shapes to bark textures. Our work-flow is built around a supervised classification that automatically learns the most discriminative features from thousands of trees and corresponding, publicly available tree inventory data. In addition, we introduce a change tracker that recognizes changes of individual trees at city-scale, which is essential to keep an urban tree inventory up-to-date. The system takes street-level images of the same tree location at two different times and classifies the type of change (e.g., tree has been removed). Drawing on recent advances in computer vision and machine learning, we apply convolutional neural networks (CNN) for all classification tasks. We propose the following pipeline: download all available panoramas and overhead images of an area of interest, detect trees per image and combine multi-view detections in a probabilistic framework, adding prior knowledge; recognize fine-grained species of detected trees. In a later, separate module, track trees over time, detect significant changes and classify the type of change. We believe this is the first work to exploit publicly available image data for city-scale street tree detection, species recognition and change tracking, exhaustively over several square kilometers, respectively many thousands of trees. Experiments in the city of Pasadena, California, USA show that we can detect >70% of the street trees, assign correct species to >80% for 40 different species, and correctly detect and classify changes in >90% of the cases.

Restoration treatments in urban park forests drive long-term changes in vegetation trajectories.

PubMed

Johnson, Lea R; Handel, Steven N

2016-04-01

Municipalities are turning to ecological restoration of urban forests as a measure to improve air quality, ameliorate urban heat island effects, improve storm water infiltration, and provide other social and ecological benefits. However, community dynamics following urban forest restoration treatments are poorly documented. This study examines the long-term effects of ecological restoration undertaken in New York City, New York, USA, to restore native forest in urban park natural areas invaded by woody non-native plants that are regional problems. In 2009 and 2010, we sampled vegetation in 30 invaded sites in three large public parks that were restored 1988-1993, and 30 sites in three large parks that were similarly invaded but had not been restored. Data from these matched plots reveal that the restoration treatment achieved its central goals. After 15-20 years, invasive species removal followed by native tree planting resulted in persistent structural and compositional shifts, significantly lower invasive species abundance, a more complex forest structure, and greater native tree recruitment. Together, these findings indicate that successional trajectories of vegetation dynamics have diverged between restored forests and invaded forests that were not restored. In addition, the data suggest that future composition of these urban forest patches will be novel assemblages. Restored and untreated sites shared a suite of shade-intolerant, quickly-growing tree species that colonize disturbed sites, indicating that restoration treatments created sites hospitable for germination and growth of species adapted to high light conditions and disturbed soils. These findings yield an urban perspective on the use of succession theory in ecological restoration. Models of ecological restoration developed in more pristine environments must be modified for use in cities. By anticipating both urban disturbances and ecological succession, management of urban forest patches can be adjusted to better predict and direct long-term outcomes. An urban approach to ecological restoration must use realistic, flexible targets to preserve and enhance urban biodiversity for both short-term benefits and long-term sustainability.

The Detection and Characterization of Urbanization, Industrialization, and Longwall Mining Impacts on Forest Ecosystems Through the Use of GiS and Remote Sensing Techniques

NASA Astrophysics Data System (ADS)

Pfeil-McCullough, Erin Kathleen

Urbanization has far reaching and significant effects on forest ecosystems, directly through urban development and indirectly through supportive processes such as coal mining and agriculture. Urban processes modify the landscape leading to altered hillslope hydrology, increased disturbance, and the introduction of non-native forest pathogens. This dissertation addresses several challenges in our ability to detect these urbanization impacts on forests via geospatial analyses. The role of forests in urban hydrological processes has been extensively studied, but the impacts of urbanized hydrology on forests remain poorly examined. This dissertation documented impacts to hydrology and forests at variety of temporal and spatial scales: 1) A geospatial comparison of the historic and contemporary forests of Allegheny County, Pennsylvania revealed substantial shifts in tree species, but less change in the species soil moisture preference. These results document additional evidence that increased heterogeneity in urban soil moisture alters forest structure. 2) To examine soil moisture changes, impacts of longwall mine subsidence were assessed by using a Landsat based canopy moisture index and hot spot analysis tools at the forest patch scale. Declines in forest canopy moisture were detected over longwall mines as mining progressed through time, and results contradicted assumptions that the hydrological impacts overlying LMS recover within 4-5 years following subsidence of undermined land. 3) Utilizing a landslide susceptibility model (SINMAP), increases in landslide susceptibility were predicted in Pittsburgh, PA based on several scenarios of ash tree loss to the emerald ash borer (EAB), a bark beetle that rapidly kills ash trees. This model provides a tool to predict changes in landslide susceptibility following tree loss, increasing the understanding of urban forest function and its role in slope stability. Detecting how urbanized hydrology impacts forest health, function, and development is fundamental to sustaining the services forests provide. Results from this dissertation will ultimately allow improvements in the management and protection of both trees and water resources in urban systems and beyond.

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

PubMed

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.

Transpiration of urban trees and its cooling effect in a high latitude city.

PubMed

Konarska, Janina; Uddling, Johan; Holmer, Björn; Lutz, Martina; Lindberg, Fredrik; Pleijel, Håkan; Thorsson, Sofia

2016-01-01

An important ecosystem service provided by urban trees is the cooling effect caused by their transpiration. The aim of this study was to quantify the magnitude of daytime and night-time transpiration of common urban tree species in a high latitude city (Gothenburg, Sweden), to analyse the influence of weather conditions and surface permeability on the tree transpiration, and to find out whether tree transpiration contributed to daytime or nocturnal cooling. Stomatal conductance and leaf transpiration at day and night were measured on mature street and park trees of seven common tree species in Gothenburg: Tilia europaea, Quercus robur, Betula pendula, Acer platanoides, Aesculus hippocastanum, Fagus sylvatica and Prunus serrulata. Transpiration increased with vapour pressure deficit and photosynthetically active radiation. Midday rates of sunlit leaves ranged from less than 1 mmol m(-2) s(-1) (B. pendula) to over 3 mmol m(-2) s(-1) (Q. robur). Daytime stomatal conductance was positively related to the fraction of permeable surfaces within the vertically projected crown area. A simple estimate of available rainwater, comprising of precipitation sum and fractional surface permeability within the crown area, was found to explain 68% of variation in midday stomatal conductance. Night-time transpiration was observed in all studied species and amounted to 7 and 20% of midday transpiration of sunlit and shaded leaves, respectively. With an estimated night-time latent heat flux of 24 W m(-2), tree transpiration significantly increased the cooling rate around and shortly after sunset, but not later in the night. Despite a strong midday latent heat flux of 206 W m(-2), a cooling effect of tree transpiration was not observed during the day.

Transpiration of urban trees and its cooling effect in a high latitude city

NASA Astrophysics Data System (ADS)

Konarska, Janina; Uddling, Johan; Holmer, Björn; Lutz, Martina; Lindberg, Fredrik; Pleijel, Håkan; Thorsson, Sofia

2016-01-01

An important ecosystem service provided by urban trees is the cooling effect caused by their transpiration. The aim of this study was to quantify the magnitude of daytime and night-time transpiration of common urban tree species in a high latitude city (Gothenburg, Sweden), to analyse the influence of weather conditions and surface permeability on the tree transpiration, and to find out whether tree transpiration contributed to daytime or nocturnal cooling. Stomatal conductance and leaf transpiration at day and night were measured on mature street and park trees of seven common tree species in Gothenburg: Tilia europaea, Quercus robur, Betula pendula, Acer platanoides, Aesculus hippocastanum, Fagus sylvatica and Prunus serrulata. Transpiration increased with vapour pressure deficit and photosynthetically active radiation. Midday rates of sunlit leaves ranged from less than 1 mmol m-2 s-1 ( B. pendula) to over 3 mmol m-2 s-1 ( Q. robur). Daytime stomatal conductance was positively related to the fraction of permeable surfaces within the vertically projected crown area. A simple estimate of available rainwater, comprising of precipitation sum and fractional surface permeability within the crown area, was found to explain 68 % of variation in midday stomatal conductance. Night-time transpiration was observed in all studied species and amounted to 7 and 20 % of midday transpiration of sunlit and shaded leaves, respectively. With an estimated night-time latent heat flux of 24 W m-2, tree transpiration significantly increased the cooling rate around and shortly after sunset, but not later in the night. Despite a strong midday latent heat flux of 206 W m-2, a cooling effect of tree transpiration was not observed during the day.

Assessing visual green effects of individual urban trees using airborne Lidar data.

PubMed

Chen, Ziyue; Xu, Bing; Gao, Bingbo

2015-12-01

Urban trees benefit people's daily life in terms of air quality, local climate, recreation and aesthetics. Among these functions, a growing number of studies have been conducted to understand the relationship between residents' preference towards local environments and visual green effects of urban greenery. However, except for on-site photography, there are few quantitative methods to calculate green visibility, especially tree green visibility, from viewers' perspectives. To fill this research gap, a case study was conducted in the city of Cambridge, which has a diversity of tree species, sizes and shapes. Firstly, a photograph-based survey was conducted to approximate the actual value of visual green effects of individual urban trees. In addition, small footprint airborne Lidar (Light detection and ranging) data was employed to measure the size and shape of individual trees. Next, correlations between visual tree green effects and tree structural parameters were examined. Through experiments and gradual refinement, a regression model with satisfactory R2 and limited large errors is proposed. Considering the diversity of sample trees and the result of cross-validation, this model has the potential to be applied to other study sites. This research provides urban planners and decision makers with an innovative method to analyse and evaluate landscape patterns in terms of tree greenness. Copyright © 2015 Elsevier B.V. All rights reserved.

Considerations for throughfall chemistry sample-size determination

Treesearch

Pamela J. Edwards; Paul Mohai; Howard G. Halverson; David R. DeWalle

1989-01-01

Both the number of trees sampled per species and the number of sampling points under each tree are important throughfall sampling considerations. Chemical loadings obtained from an urban throughfall study were used to evaluate the relative importance of both of these sampling factors in tests for determining species' differences. Power curves for detecting...

Assessing the Impact of Asian Longhorned Beetle in Worcester, MA: Thermal Effects, Community Responses, and Future Vulnerability

NASA Astrophysics Data System (ADS)

Elmes, Arthur Francis Marett

Urban environments experience air, water, noise, and heat pollution as a consequence of their composition, structure, and function. These adverse environmental conditions, which have direct and indirect effects on human health and ecological stability, can be mitigated or partially offset by healthy and extensive urban forests. Additionally, urban trees provide a number of cultural, aesthetic, and property value benefits. However, to provide maximum ecosystem service benefits, an urban forest must be carefully planned and maintained, so that average tree lifespan is maximized and ecological vulnerability is minimized. Maximal urban forest resilience is best achieved via taxonomic and age-diversity, such that no one genus or age-cohort dominates. This diversity enhances overall urban forest resilience, which in turn facilitates maximum ecosystem service provision. The Asian Longhorned Beetle (ALB, Anoplophora glabripennis) infestation in Worcester, MA represents a case example of taxonomic monoculture vulnerability, but also an excellent opportunity to reinvest and diversify the urban forest. As a result of the ALB infestation, which was first documented in 2008, approximately 35,000 host trees were removed from residential and public property, substantially reducing urban tree canopy coverage and uncovering impervious surfaces. Chapter two quantifies this Urban Tree Canopy (UTC) loss, and shows that in loss areas Land Surface Temperature (LST) increases range from 1 - 6° C. The research investigates multi-scale effects of this relationship, particularly in the hard-hit Burncoat and Greendale neighborhoods of Worcester, MA. In response to the large quantity of UTC loss suffered due to ALB, the Massachusetts Department of Conservation and Recreation (DCR), the City of Worcester, and the Worcester Tree Initiative (WTI) have together planted over 30,000 trees, primarily via tree giveaway programs to local residents. Chapter three assesses the effectiveness of this initiative in terms of juvenile tree mortality rates - a critical indicator of long-term urban forest success. Results indicate that tree stewardship variables such as renter proportion and number of trees planted per property are strong predictors of tree mortality. Tree species was shown to be strong predictor of mortality, with ornamental trees showing lower mortality rates than shade deciduous or conifers. Finally, Chapter four investigates the potential risk of further ALB infestation in the Worcester area, using a circuit theory dispersal model, which uses an analogy with electrical circuits to predict the dispersal of random-walkers across a heterogeneous landscape. The results indicate that impervious surfaces such as roads, sidewalks, and parking lots, as well as proximity to existing trees are facilitators of ALB movement. Circuit-based dispersal maps highlight the importance of narrow dispersal corridors connecting larger areas of potential dispersal. Dispersal potential was combined with ALB habitat suitability measured with Mahalanobis typicality, yielding a hybrid map of ALB infestation risk. These map products are valuable both as contributions to the understanding of invasive species movement in novel environments, and as tools for land managers attempting to eradicate ALB, such as the USDA Animal and Plant Health Inspection Service. This dissertation investigates three elements of the ALB infestation of Worcester, providing a holistic explanation of the impacts, recovery, and vulnerability of Worcester's urban forest.

Urban trees and forests of the Chicago region

Treesearch

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...

Habitat preferences of two sparrow species are modified by abundances of other birds in an urban environment

PubMed Central

Skórka, Piotr; Sierpowska, Katarzyna; Haidt, Andżelika; Myczko, Łukasz; Ekner-Grzyb, Anna; Rosin, Zuzanna M.; Kwieciński, Zbigniew; Suchodolska, Joanna; Takacs, Viktoria; Jankowiak, Łukasz; Wasielewski, Oskar; Graclik, Agnieszka; Krawczyk, Agata J.; Kasprzak, Adam; Szwajkowski, Przemysław; Wylegała, Przemysław; Malecha, Anna W.; Mizera, Tadeusz; Tryjanowski, Piotr

2016-01-01

Abstract Every species has certain habitat requirements, which may be altered by interactions with other co-occurring species. These interactions are mostly ignored in predictive models trying to identify key habitat variables correlated with species population abundance/occurrence. We investigated how the structure of the urban landscape, food resources, potential competitors, predators, and interaction between these factors influence the abundance of house sparrow Passer domesticus and the tree sparrow P. montanus in sixty 25 ha plots distributed randomly across residential areas of the city of Poznań (Poland). The abundance of the house sparrow was positively correlated with the abundance of pigeons but negatively correlated with human-related food resources. There were significant interaction terms between abundances of other urban species and habitat variables in statistical models. For example, the abundance of house sparrow was negatively correlated with the abundance of corvids and tree sparrows but only when food resources were low. The abundance of tree sparrows positively correlated with density of streets and the distance from the city center. The abundance of this species positively correlated with the abundance of corvids when food resources were low but negatively correlated at low covers of green area. Our study indicates that associations between food resources, habitat covers, and the relative abundance of two sparrow species are altered by the abundance of other urban species. Competition, niche separation and social facilitation may be responsible for these interactive effects. Thus, biotic interactions should be included not only as an additive effect but also as an interaction term between abundance and habitat variables in statistical models predicting species abundance and occurrence. PMID:29491924

Effects of urban tree management and species selection on atmospheric carbon dioxide

Treesearch

David J. Nowak; Jack C. Stevens; Susan M. Sisinni; Christopher J. Luley

2002-01-01

Trees sequester and store carbon in their tissue at differing rates and amounts based on such factors as tree size at maturity, life span, and growth rate. Concurrently, tree care practices release carbon back to the atmosphere based on fossil-fuel emissions from maintenance equipment (e.g., chain saws, trucks, chippers). Management choices such as tree locations for...

Tree health mapping with multispectral remote sensing data at UC Davis, California

Treesearch

Q. Xiao; E.G. McPherson

2005-01-01

Tree health is a critical parameter for evaluating urban ecosystem health and sustainability. Tradi­tionally, this parameter has been derived from field surveys. We used multispectral remote sensing data and GIS techniques to determine tree health at the University of California, Davis. The study area (363 ha) contained 8,962 trees of 215 species. Tree health...

Equations for predicting diameter, height, crown width, and leaf area of San Joaquin Valley street trees

Treesearch

P.J. Peper; E.G. McPherson; S.M. Mori

2001-01-01

Although the modeling of energy-use reduction, air pollution uptake, rainfall interception, and microclimate modification associated with urban trees depends on data relating diameter at breast height (dbh) , crown height, crown diameter, and leaf area to tree age or dbh, scant information is available for common municipal tree species . I n this study , tree height ,...

Urban trees reduce nutrient leaching to groundwater.

PubMed

Nidzgorski, Daniel A; Hobbie, Sarah E

2016-07-01

Many urban waterways suffer from excess nitrogen (N) and phosphorus (P), feeding algal blooms, which cause lower water clarity and oxygen levels, bad odor and taste, and the loss of desirable species. Nutrient movement from land to water is likely to be influenced by urban vegetation, but there are few empirical studies addressing this. In this study, we examined whether or not urban trees can reduce nutrient leaching to groundwater, an important nutrient export pathway that has received less attention than stormwater. We characterized leaching beneath 33 trees of 14 species, and seven open turfgrass areas, across three city parks in Saint Paul, Minnesota, USA. We installed lysimeters at 60 cm depth to collect soil water approximately biweekly from July 2011 through October 2013, except during winter and drought periods, measured dissolved organic carbon (C), N, and P in soil water, and modeled water fluxes using the BROOK90 hydrologic model. We also measured soil nutrient pools (bulk C and N, KCl-extractable inorganic N, Brays-P), tree tissue nutrient concentrations (C, N, and P of green leaves, leaf litter, and roots), and canopy size parameters (leaf biomass, leaf area index) to explore correlations with nutrient leaching. Trees had similar or lower N leaching than turfgrass in 2012 but higher N leaching in 2013; trees reduced P leaching compared with turfgrass in both 2012 and 2013, with lower leaching under deciduous than evergreen trees. Scaling up our measurements to an urban subwatershed of the Mississippi River (~17 400 ha, containing ~1.5 million trees), we estimated that trees reduced P leaching to groundwater by 533 kg in 2012 (0.031 kg/ha or 3.1 kg/km 2 ) and 1201 kg in 2013 (0.069 kg/ha or 6.9 kg/km 2 ). Removing these same amounts of P using stormwater infrastructure would cost $2.2 million and $5.0 million per year (2012 and 2013 removal amounts, respectively). © 2016 by the Ecological Society of America.

Photosynthesis and aboveground carbon allocation of two co-occurring poplar species in an urban brownfield.

PubMed

Radwanski, Diane; Gallagher, Frank; Vanderklein, Dirk W; Schäfer, Karina V R

2017-04-01

Phytoremediation, a technique used to reclaim heavy metal-contaminated soils, requires an understanding of plant physiological responses to heavy metals. However, the majority of studies documenting heavy metal impact on plant functioning have been performed in laboratory or greenhouse settings. We predicted that increased soil heavy metal concentrations reduce photosynthesis and biomass production in trees growing in metal contaminated soil in a naturally re-vegetated urban brownfield. Leaf gas exchange, leaf carbon and nitrogen concentration, and tree biomass were recorded and compared for Populus deltoides and Populus tremuloides growing in an urban brownfield. The CO 2 compensation point (CCP) differed significantly between soil metal concentrations and species, with P. deltoides displaying a greater CCP and P. tremuloides displaying a lower CCP as soil metal concentration increased, despite no changes in dark respiration for either species. In terms of biomass, only total branch weight (TBW) and leaf area (LA) differed significantly between soil metal concentrations, though the difference was largely attributable to variation in diameter at breast height (DBH). Furthermore, TBW and LA values for P. deltoides did not decrease with increasing soil metal concentration. Soil metal concentration, thus, had minimal effect on the relationship between tree age and DBH, and no effect on relationships of tree age and height or LA, respectively. Significant differences between soil metal concentrations and species were found for δ 15 N (isotopic nitrogen ratio) while leaf nitrogen content (% N) also differed significantly between species. Long-term water use efficiency derived from carbon isotope analysis (iWUE isotope ) differed significantly between trees grown on different soil metal concentrations and a significant species-metal concentration interaction was detected indicating that the two study species responded differentially to the soil metal concentrations. Specifically, P. tremuloides enhanced while P. deltoides reduced long-term iWUE isotope as soil metal concentration increased, further emphasizing the importance of species and possible genotype selection for phytoremediation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Grading of parameters for urban tree inventories by city officials, arborists, and academics using the delphi method.

PubMed

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.

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

NASA Astrophysics Data System (ADS)

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.

Mosses Are Better than Leaves of Vascular Plants in Monitoring Atmospheric Heavy Metal Pollution in Urban Areas.

PubMed

Jiang, Yanbin; Fan, Miao; Hu, Ronggui; Zhao, Jinsong; Wu, Yupeng

2018-05-29

Mosses and leaves of vascular plants have been used as bioindicators of environmental contamination by heavy metals originating from various sources. This study aims to compare the metal accumulation capabilities of mosses and vascular species in urban areas and quantify the suitability of different taxa for monitoring airborne heavy metals. One pleurocarpous feather moss species, Haplocladium angustifolium , and two evergreen tree species, Cinnamomum bodinieri Osmanthus fragrans , and substrate soil were sampled in the urban area of different land use types in Wuhan City in China. The concentrations of Ag, As, Cd, Co, Cr, Cu, Mn, Mo, Ni, V, Pb, and Zn in these samples were analyzed by inductively coupled plasma mass spectrometry. The differences of heavy metals concentration in the three species showed that the moss species was considerably more capable of accumulating heavy metals than tree leaves (3 times to 51 times). The accumulated concentration of heavy metals in the moss species depended on the metal species and land use type. The enrichment factors of metals for plants and the correlations of metals in plants with corresponding metals in soil reflected that the accumulated metals in plants stemmed mostly from atmospheric deposition, rather than the substrate soil. Anthropogenic factors, such as traffic emissions from automobile transportation and manufacturing industries, were primarily responsible for the variations in metal pollutants in the atmosphere and subsequently influenced the metal accumulation in the mosses. This study elucidated that the moss species H. angustifolium is relatively more suitable than tree leaves of C. bodinieri and O. fragrans in monitoring heavy metal pollution in urban areas, and currently Wuhan is at a lower contamination level of atmospheric heavy metals than some other cities in China.

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

NASA Astrophysics Data System (ADS)

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

2012-03-01

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, horse chestnut, honey locust, and hawthorn. 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 vegetative state for crabapple and honey locust. Total normalized (30 °C) monoterpene emissions from honey locust were higher during flowering (5.26 μg Cg-1 h-1) than after flowering (1.23 μg Cg-1 h-1). The total normalized BVOC emission rate from crabapple (93 μg Cg-1 h-1) during the flowering period is of the same order as isoprene emissions from oak trees, which are among the highest BVOC emissions observed from plants to date. These findings illustrate that during the relatively brief springtime flowering period, floral emissions constitute by far the most significant contribution to the BVOC flux from these tree species, some of which are leafless at this time. Experimental results were integrated into the MEGAN biogenic emission model and simulations were performed to estimate the contribution of floral BVOC emissions to the total urban BVOC flux during the spring flowering period. The floral BVOC emitted during this three-month simulation are equivalent to 11 % of the cumulative monoterpene flux for the Boulder urban area.

Simplification of arboreal marsupial assemblages in response to increasing urbanization.

PubMed

Isaac, Bronwyn; White, John; Ierodiaconou, Daniel; Cooke, Raylene

2014-01-01

Arboreal marsupials play an essential role in ecosystem function including regulating insect and plant populations, facilitating pollen and seed dispersal and acting as a prey source for higher-order carnivores in Australian environments. Primarily, research has focused on their biology, ecology and response to disturbance in forested and urban environments. We used presence-only species distribution modelling to understand the relationship between occurrences of arboreal marsupials and eco-geographical variables, and to infer habitat suitability across an urban gradient. We used post-proportional analysis to determine whether increasing urbanization affected potential habitat for arboreal marsupials. The key eco-geographical variables that influenced disturbance intolerant species and those with moderate tolerance to disturbance were natural features such as tree cover and proximity to rivers and to riparian vegetation, whereas variables for disturbance tolerant species were anthropogenic-based (e.g., road density) but also included some natural characteristics such as proximity to riparian vegetation, elevation and tree cover. Arboreal marsupial diversity was subject to substantial change along the gradient, with potential habitat for disturbance-tolerant marsupials distributed across the complete gradient and potential habitat for less tolerant species being restricted to the natural portion of the gradient. This resulted in highly-urbanized environments being inhabited by a few generalist arboreal marsupial species. Increasing urbanization therefore leads to functional simplification of arboreal marsupial assemblages, thus impacting on the ecosystem services they provide.

Simplification of Arboreal Marsupial Assemblages in Response to Increasing Urbanization

PubMed Central

Isaac, Bronwyn; White, John; Ierodiaconou, Daniel; Cooke, Raylene

2014-01-01

Arboreal marsupials play an essential role in ecosystem function including regulating insect and plant populations, facilitating pollen and seed dispersal and acting as a prey source for higher-order carnivores in Australian environments. Primarily, research has focused on their biology, ecology and response to disturbance in forested and urban environments. We used presence-only species distribution modelling to understand the relationship between occurrences of arboreal marsupials and eco-geographical variables, and to infer habitat suitability across an urban gradient. We used post-proportional analysis to determine whether increasing urbanization affected potential habitat for arboreal marsupials. The key eco-geographical variables that influenced disturbance intolerant species and those with moderate tolerance to disturbance were natural features such as tree cover and proximity to rivers and to riparian vegetation, whereas variables for disturbance tolerant species were anthropogenic-based (e.g., road density) but also included some natural characteristics such as proximity to riparian vegetation, elevation and tree cover. Arboreal marsupial diversity was subject to substantial change along the gradient, with potential habitat for disturbance-tolerant marsupials distributed across the complete gradient and potential habitat for less tolerant species being restricted to the natural portion of the gradient. This resulted in highly-urbanized environments being inhabited by a few generalist arboreal marsupial species. Increasing urbanization therefore leads to functional simplification of arboreal marsupial assemblages, thus impacting on the ecosystem services they provide. PMID:24608165

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

Treesearch

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...

Assessing urban forest effects and values: Douglas County, Kansas

Treesearch

David J. Nowak; Allison R. Bodine; Robert E. Hoehn; Alexis Ellis; Kim Bomberger; Daniel E. Crane; Theodore A. Endreny; Thomas Taggert; Emily. Stephan

2014-01-01

An analysis of trees in Douglas County, Kansas, reveals that this area has about 14,164,000 trees with tree and shrub canopy that covers 25.2 percent of the county. The most common tree species are American elm, northern hackberry, eastern redcedar, Osage-orange, and honeylocust. Trees in Douglas County currently store about 1.7 million tons of carbon (6.4 million tons...

Assessing urban forest effects and values: the greater Kansas City region

Treesearch

David J. Nowak; Allison R. Bodine; Robert E. III Hoehn; Daniel E. Crane; Alexis Ellis; Theodore A. Endreny; Yang Yang; Tom Jacobs; Kassie Shelton

2013-01-01

An analysis of trees in the greater Kansas City region of Missouri and Kansas reveals that this area has about 249,450,000 trees with tree and shrub canopy that covers 28.3 percent of the region. The most common tree species are American elm, northern hackberry, Osage-orange, honeylocust, and eastern redcedar. Trees in the greater Kansas City region currently store...

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

PubMed

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 development by selection of specific pollutant tolerant tree species and leaf traits, which is suitable as air pollution mitigation measure. Copyright © 2018 Elsevier Inc. All rights reserved.

The future of large old trees in urban landscapes.

PubMed

Le Roux, Darren S; Ikin, Karen; Lindenmayer, David B; Manning, Adrian D; Gibbons, Philip

2014-01-01

Large old trees are disproportionate providers of structural elements (e.g. hollows, coarse woody debris), which are crucial habitat resources for many species. The decline of large old trees in modified landscapes is of global conservation concern. Once large old trees are removed, they are difficult to replace in the short term due to typically prolonged time periods needed for trees to mature (i.e. centuries). Few studies have investigated the decline of large old trees in urban landscapes. Using a simulation model, we predicted the future availability of native hollow-bearing trees (a surrogate for large old trees) in an expanding city in southeastern Australia. In urban greenspace, we predicted that the number of hollow-bearing trees is likely to decline by 87% over 300 years under existing management practices. Under a worst case scenario, hollow-bearing trees may be completely lost within 115 years. Conversely, we predicted that the number of hollow-bearing trees will likely remain stable in semi-natural nature reserves. Sensitivity analysis revealed that the number of hollow-bearing trees perpetuated in urban greenspace over the long term is most sensitive to the: (1) maximum standing life of trees; (2) number of regenerating seedlings ha(-1); and (3) rate of hollow formation. We tested the efficacy of alternative urban management strategies and found that the only way to arrest the decline of large old trees requires a collective management strategy that ensures: (1) trees remain standing for at least 40% longer than currently tolerated lifespans; (2) the number of seedlings established is increased by at least 60%; and (3) the formation of habitat structures provided by large old trees is accelerated by at least 30% (e.g. artificial structures) to compensate for short term deficits in habitat resources. Immediate implementation of these recommendations is needed to avert long term risk to urban biodiversity.

The Future of Large Old Trees in Urban Landscapes

PubMed Central

Le Roux, Darren S.; Ikin, Karen; Lindenmayer, David B.; Manning, Adrian D.; Gibbons, Philip

2014-01-01

Large old trees are disproportionate providers of structural elements (e.g. hollows, coarse woody debris), which are crucial habitat resources for many species. The decline of large old trees in modified landscapes is of global conservation concern. Once large old trees are removed, they are difficult to replace in the short term due to typically prolonged time periods needed for trees to mature (i.e. centuries). Few studies have investigated the decline of large old trees in urban landscapes. Using a simulation model, we predicted the future availability of native hollow-bearing trees (a surrogate for large old trees) in an expanding city in southeastern Australia. In urban greenspace, we predicted that the number of hollow-bearing trees is likely to decline by 87% over 300 years under existing management practices. Under a worst case scenario, hollow-bearing trees may be completely lost within 115 years. Conversely, we predicted that the number of hollow-bearing trees will likely remain stable in semi-natural nature reserves. Sensitivity analysis revealed that the number of hollow-bearing trees perpetuated in urban greenspace over the long term is most sensitive to the: (1) maximum standing life of trees; (2) number of regenerating seedlings ha−1; and (3) rate of hollow formation. We tested the efficacy of alternative urban management strategies and found that the only way to arrest the decline of large old trees requires a collective management strategy that ensures: (1) trees remain standing for at least 40% longer than currently tolerated lifespans; (2) the number of seedlings established is increased by at least 60%; and (3) the formation of habitat structures provided by large old trees is accelerated by at least 30% (e.g. artificial structures) to compensate for short term deficits in habitat resources. Immediate implementation of these recommendations is needed to avert long term risk to urban biodiversity. PMID:24941258

A citizen science campaign encouraging urban forest professionals to engage the public in the collection of tree phenological data

NASA Astrophysics Data System (ADS)

Clarke, K. C.

2009-12-01

There are growing concerns among leading national and local organizations about American scientific literacy, fundamental understanding of science, and the value of scientific research. These organizations, including the University Corporation for Atmospheric Research, have been at the forefront in addressing these concerns. In an effort to improve scientific literacy, research conducted by Sam Droege, among others, suggested using citizen science and public participation as instrumental methods to engage the public. Urban Tree Phenology (UTP), a project of Project BudBurst and the USDA Forest Service, is one such citizen science program that sought to engage the public, including the professionals and amateurs among them, in collecting urban tree phenophase data. UTP participants monitored and reported the stages of phenological events, such as First Leaf and Leaf Fall, of 24 native and cultivated urban tree species, using the steps shown in Figure 1. Data collected will support the long-term research of plant ecology, climate change, public health, urban heat islands on tree physiology, and urban tree management. UTP, using the architectures of online learning, has developed two instructional tutorials to assist data collection (Phase 1). The instructional tutorials were published online, in print and PowerPoint formats, at www.UrbanTreePhenology.com. By completing these tutorials, participants will gain the skills necessary to provide urban tree phenological data to national research databases via the Internet. Phase 2 will test and review the instructional materials developed, and in Phase 3, the administrators of UTP will distribute promotional materials to national research organizations and to participants of the Project BudBurst national citizen science campaign.

Biogenic volatile organic compounds from the urban forest of the Metropolitan Region, Chile.

PubMed

Préndez, Margarita; Carvajal, Virginia; Corada, Karina; Morales, Johanna; Alarcón, Francis; Peralta, Hugo

2013-12-01

Tropospheric ozone is a secondary pollutant whose primary sources are volatile organic compounds and nitrogen oxides. The national standard is exceeded on a third of summer days in some areas of the Chilean Metropolitan Region (MR). This study reports normalized springtime experimental emissions factors (EF) for biogenic volatile organic compounds from tree species corresponding to approximately 31% of urban trees in the MR. A Photochemical Ozone Creation Index (POCI) was calculated using Photochemical Ozone Creation Potential of quantified terpenes. Ten species, natives and exotics, were analysed using static enclosure technique. Terpene quantification was performed using GC-FID, thermal desorption, cryogenic concentration and automatic injection. Observed EF and POCI values for terpenes from exotic species were 78 times greater than native values; within the same family, exotic EF and POCI values were 28 and 26 times greater than natives. These results support reforestation with native species for improved urban pollution management. Copyright © 2013 Elsevier Ltd. All rights reserved.

Temporal dynamics of a subtropical urban forest in San Juan, Puerto Rico, 2001-2010

Treesearch

J. M. Tucker Lima; C. L. Staudhammer; T. J. Brandeis; F. J. Escobedo; W. Zipperer

2013-01-01

Several studies report urban tree growth and mortality rates as well as species composition, structural dynamics, and other characteristics of urban forests in mostly temperate, inland urban areas. Temporal dynamics of urban forests in subtropical and tropical forest regions are, until now, little explored and represent a new and important direction for study and...

Urban bat communities are affected by wetland size, quality, and pollution levels.

PubMed

Straka, Tanja Maria; Lentini, Pia Eloise; Lumsden, Linda Faye; Wintle, Brendan Anthony; van der Ree, Rodney

2016-07-01

Wetlands support unique biota and provide important ecosystem services. These services are highly threatened due to the rate of loss and relative rarity of wetlands in most landscapes, an issue that is exacerbated in highly modified urban environments. Despite this, critical ecological knowledge is currently lacking for many wetland-dependent taxa, such as insectivorous bats, which can persist in urban areas if their habitats are managed appropriately. Here, we use a novel paired landscape approach to investigate the role of wetlands in urban bat conservation and examine local and landscape factors driving bat species richness and activity. We acoustically monitored bat activity at 58 urban wetlands and 35 nonwetland sites (ecologically similar sites without free-standing water) in the greater Melbourne area, southeastern Australia. We analyzed bat species richness and activity patterns using generalized linear mixed-effects models. We found that the presence of water in urban Melbourne was an important driver of bat species richness and activity at a landscape scale. Increasing distance to bushland and increasing levels of heavy metal pollution within the waterbody also negatively influenced bat richness and individual species activity. Areas with high levels of artificial night light had reduced bat species richness, and reduced activity for all species except those adapted to urban areas, such as the White-striped free-tailed bat (Austronomus australis). Increased surrounding tree cover and wetland size had a positive effect on bat species richness. Our findings indicate that wetlands form critical habitats for insectivorous bats in urban environments. Large, unlit, and unpolluted wetlands flanked by high tree cover in close proximity to bushland contribute most to the richness of the bat community. Our findings clarify the role of wetlands for insectivorous bats in urban areas and will also allow for the preservation, construction, and management of wetlands that maximize conservation outcomes for urban bats and possibly other wetland-dependent and nocturnal fauna.

Estimating urban trees and carbon stock potentials for mitigating climate change in Lagos: Case of Ikeja Government Reserved Area (GRA)

NASA Astrophysics Data System (ADS)

Elias, P. O.; Faderin, A.

2014-12-01

Urban trees are a component of the urban infrastructure which offers diverse services including environmental, aesthetic and economic. The accumulation of carbon in the atmosphere resulting from the indiscriminate distribution of human populations and urban activities with the unsustainable consumption of natural resources contributes to global environmental change especially in coastal cities like Lagos. Carbon stocks and sequestration by urban trees are increasingly recognized to play significant roles for mitigating climate change. This paper focuses on the estimation of carbon stock and sequestration through biomass estimation and quantification in Ikeja GRA, Lagos. Ikeja possesses a characteristic feature as a microcosm of Lagos due to the wide range of land uses. A canopy assessment of tree population was carried out using itree canopy software. A GPS survey was used to collect an inventory of all trees showing their location, spatial distribution and other attributes. The analysis of the carbon storage and sequestration potential of both actual and potential tree planting sites involved biomass estimations from tree allometry equations. Trees were identified at species level and measurements of their dendrometric values were recorded and integrated into the GIS database to estimate biomass of trees and carbon storage. The trees in the study area were estimated to have a biomass of 441.9 mg and carbon storage of 221.395 kg/tree. By considering the potential tree planting sites the estimated carbon stored increased to 11,352.73 kg. Carbon sequestration value in the study area was found to be 1.6790 tonnes for the existing trees and 40.707 tonnes for the potential tree planting sites (PTPS). The estimation of carbon storage and sequestration values of trees are important incentives for carbon accounting/footprints and monitoring of climate change mitigation which has implications for evaluation and monitoring of urban ecosystem.

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

PubMed

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.

Aspen succession and nitrogen loading: a case for epiphytic lichens as bioindicators in the Rocky Mountains, USA

Treesearch

Paul C. Rogers; Kori D. Moore; Ronald J. Ryel

2009-01-01

Forty-seven randomly selected mid-elevation aspen stands were sampled for lichens and stand conditions. Plots were characterized according to tree species cover, basal area, stand age, bole scarring, tree damage, and presence of lichen species. We also recorded ammonia emissions with passive sensors at 25 urban and agricultural sites throughout an adjacent populated...

Surface water storage capacity of twenty tree species in Davis, California

Treesearch

Qingfu Xiao; E. Gregory McPherson

2016-01-01

Urban forestry is an important green infrastructure strategy because healthy trees can intercept rainfall, reducing stormwater runoff and pollutant loading. Surface saturation storage capacity, defined as the thin film of water that must wet tree surfaces before flow begins, is the most important variable influencing rainfall interception processes. Surface storage...

Human and biophysical legacies shape contemporary urban forests: A literature synthesis

Treesearch

Lara A. Roman; Hamil Pearsall; Theodore S. Eisenman; Tenley M. Conway; Robert T. Fahey; Shawn Landry; Jess Vogt; Natalie S. van Doorn; J. Morgan Grove; Dexter H. Locke; Adrina C. Bardekjian; John J. Battles; Mary L. Cadenasso; Cecil C. Konijnendijk van den Bosch; Meghan Avolio; Adam Berland; G. Darrel Jenerette; Sarah K. Mincey; Diane E. Pataki; Christina Staudhammer

2018-01-01

Understanding how urban forests developed their current patterns of tree canopy cover, species composition, and diversity requires an appreciation of historical legacy effects. However, analyses of current urban forest characteristics are often limited to contemporary socioeconomic factors, overlooking the role of history. The institutions, human communities, and...

Climate tolerances and trait choices shape continental patterns of urban tree biodiversity

Treesearch

G. Darrel Jenerette; Lorraine W. Clarke; Meghan L. Avolio; Diane E. Pataki; Thomas W. Gillespie; Stephanie Pincetl; Dave J. Nowak; Lucy R. Hutyra; Melissa McHale; Joseph P. McFadden; Michael Alonzo

2016-01-01

Aim. We propose and test a climate tolerance and trait choice hypothesis of urban macroecological variation in which strong filtering associated with low winter temperatures restricts urban biodiversity while weak filtering associated with warmer temperatures and irrigation allows dispersal of species from a global source pool, thereby...

Morphometric Variation on the Cypress Aphid Cinara cupressi (Buckton) (Hemiptera: Aphididae) Associated to Urban Trees.

PubMed

Ruiz, C; Lanfranco, D; Carrillo, R; Parra, L

2014-06-01

Cinara cupressi (Buckton) is an important aphid pest of the Cupressaceae family, originally reported in Chile in 2003. Since then, it has spread over 4,000 km, contributing to conservation issues, mostly associated with native and urban trees of the Cupressaceae. In the present work, the morphometric variation of C. cupressi was examined to determine if the species present in Chile corresponds to a specific entity, and to identify variations among specimens from different localities in the study area. Colonies were collected from urban trees from northern, central, and southern Chile. Morphometric data for 14 characters in aphids from 63 localities in all the distribution ranges were measured and analyzed by multivariate analysis. Results showed that the species present in Chile corresponds to C. cupressi like a single specific entity, showing no morphological variation across the regions sampled. Our data will be discussed within the context of correct taxonomic identification for the implementation of effective biological control strategies.

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

PubMed

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 scale of the desired biophysical effect and an awareness of a range of impacts guide the choice of i) tree species, ii) location and iii) density of tree placement, street trees can be an important tool for urban planners and designers in developing resilient and resourceful cities in an era of climatic change.

Greener cities: U.S. Forest Service software package helps cities manage their urban treescape

Treesearch

Jim Kling; Greg Featured: McPherson

2008-01-01

Urban forests don't get the recognition that natural forests do. They don't encompass sweeping vistas and magnificent views and they don't provide critical habitat to endangered species. Nevertheless, they are vital. More than 90 percent of all Californians live, work, and play in urban forests. Trees in the urban landscape provide vital ecosystem...

Automated identification and geometrical features extraction of individual trees from Mobile Laser Scanning data in Budapest

NASA Astrophysics Data System (ADS)

Koma, Zsófia; Székely, Balázs; Folly-Ritvay, Zoltán; Skobrák, Ferenc; Koenig, Kristina; Höfle, Bernhard

2016-04-01

Mobile Laser Scanning (MLS) is an evolving operational measurement technique for urban environment providing large amounts of high resolution information about trees, street features, pole-like objects on the street sides or near to motorways. In this study we investigate a robust segmentation method to extract the individual trees automatically in order to build an object-based tree database system. We focused on the large urban parks in Budapest (Margitsziget and Városliget; KARESZ project) which contained large diversity of different kind of tree species. The MLS data contained high density point cloud data with 1-8 cm mean absolute accuracy 80-100 meter distance from streets. The robust segmentation method contained following steps: The ground points are determined first. As a second step cylinders are fitted in vertical slice 1-1.5 meter relative height above ground, which is used to determine the potential location of each single trees trunk and cylinder-like object. Finally, residual values are calculated as deviation of each point from a vertically expanded fitted cylinder; these residual values are used to separate cylinder-like object from individual trees. After successful parameterization, the model parameters and the corresponding residual values of the fitted object are extracted and imported into the tree database. Additionally, geometric features are calculated for each segmented individual tree like crown base, crown width, crown length, diameter of trunk, volume of the individual trees. In case of incompletely scanned trees, the extraction of geometric features is based on fitted circles. The result of the study is a tree database containing detailed information about urban trees, which can be a valuable dataset for ecologist, city planners, planting and mapping purposes. Furthermore, the established database will be the initial point for classification trees into single species. MLS data used in this project had been measured in the framework of KARESZ project for whole Budapest. BSz contributed as an Alexander von Humboldt Research Fellow.

Tree Classification with Fused Mobile Laser Scanning and Hyperspectral Data

PubMed Central

Puttonen, Eetu; Jaakkola, Anttoni; Litkey, Paula; Hyyppä, Juha

2011-01-01

Mobile Laser Scanning data were collected simultaneously with hyperspectral data using the Finnish Geodetic Institute Sensei system. The data were tested for tree species classification. The test area was an urban garden in the City of Espoo, Finland. Point clouds representing 168 individual tree specimens of 23 tree species were determined manually. The classification of the trees was done using first only the spatial data from point clouds, then with only the spectral data obtained with a spectrometer, and finally with the combined spatial and hyperspectral data from both sensors. Two classification tests were performed: the separation of coniferous and deciduous trees, and the identification of individual tree species. All determined tree specimens were used in distinguishing coniferous and deciduous trees. A subset of 133 trees and 10 tree species was used in the tree species classification. The best classification results for the fused data were 95.8% for the separation of the coniferous and deciduous classes. The best overall tree species classification succeeded with 83.5% accuracy for the best tested fused data feature combination. The respective results for paired structural features derived from the laser point cloud were 90.5% for the separation of the coniferous and deciduous classes and 65.4% for the species classification. Classification accuracies with paired hyperspectral reflectance value data were 90.5% for the separation of coniferous and deciduous classes and 62.4% for different species. The results are among the first of their kind and they show that mobile collected fused data outperformed single-sensor data in both classification tests and by a significant margin. PMID:22163894

Tree classification with fused mobile laser scanning and hyperspectral data.

PubMed

Puttonen, Eetu; Jaakkola, Anttoni; Litkey, Paula; Hyyppä, Juha

2011-01-01

Mobile Laser Scanning data were collected simultaneously with hyperspectral data using the Finnish Geodetic Institute Sensei system. The data were tested for tree species classification. The test area was an urban garden in the City of Espoo, Finland. Point clouds representing 168 individual tree specimens of 23 tree species were determined manually. The classification of the trees was done using first only the spatial data from point clouds, then with only the spectral data obtained with a spectrometer, and finally with the combined spatial and hyperspectral data from both sensors. Two classification tests were performed: the separation of coniferous and deciduous trees, and the identification of individual tree species. All determined tree specimens were used in distinguishing coniferous and deciduous trees. A subset of 133 trees and 10 tree species was used in the tree species classification. The best classification results for the fused data were 95.8% for the separation of the coniferous and deciduous classes. The best overall tree species classification succeeded with 83.5% accuracy for the best tested fused data feature combination. The respective results for paired structural features derived from the laser point cloud were 90.5% for the separation of the coniferous and deciduous classes and 65.4% for the species classification. Classification accuracies with paired hyperspectral reflectance value data were 90.5% for the separation of coniferous and deciduous classes and 62.4% for different species. The results are among the first of their kind and they show that mobile collected fused data outperformed single-sensor data in both classification tests and by a significant margin.

Nest design in a changing world: great tit Parus major nests from a Mediterranean city environment as a case study.

PubMed

Lambrechts, Marcel M; Charmantier, Anne; Demeyrier, Virginie; Lucas, Annick; Perret, Samuel; Abouladzé, Matthieu; Bonnet, Michel; Canonne, Coline; Faucon, Virginie; Grosset, Stéphanie; le Prado, Gaëlle; Lidon, Frédéric; Noell, Thierry; Pagano, Pascal; Perret, Vincent; Pouplard, Stéphane; Spitaliéry, Rémy; Bernard, Cyril; Perret, Philippe; Blondel, Jacques; Grégoire, Arnaud

2017-12-01

Investigations of urbanization effects on birds have focused mainly on breeding traits expressed after the nest-building stage (e.g. first-egg date, clutch size, breeding success, and offspring characteristics). Urban studies largely ignored how and why the aspects of nest building might be associated with the degree of urbanization. As urban environments are expected to present novel environmental changes relative to rural environments, it is important to evaluate how nest-building behavior is impacted by vegetation modifications associated with urbanization. To examine nest design in a Mediterranean city environment, we allowed urban great tits ( Parus major ) to breed in nest boxes in areas that differed in local vegetation cover. We found that different measures of nest size or mass were not associated with vegetation cover. In particular, nests located adjacent to streets with lower vegetation cover were not smaller or lighter than nests in parks with higher vegetation cover. Nests adjacent to streets contained more pine needles than nests in parks. In addition, in nests adjacent to streets, nests from boxes attached to pine trees contained more pine needles than nests from boxes attached to other trees. We suggest that urban-related alterations in vegetation cover do not directly impose physical limits on nest size in species that are opportunistic in the selection of nesting material. However, nest composition as reflected in the use of pine needles was clearly affected by habitat type and the planted tree species present, which implies that rapid habitat change impacts nest composition. We do not exclude that urbanization might impact other aspects of nest building behaviour not covered in our study (e.g. costs of searching for nest material), and that the strengths of the associations between urbanization and nest structures might differ among study populations or species.

Leaf phenological characters of main tree species in urban forest of Shenyang.

PubMed

Xu, Sheng; Xu, Wenduo; Chen, Wei; He, Xingyuan; Huang, Yanqing; Wen, Hua

2014-01-01

Plant leaves, as the main photosynthetic organs and the high energy converters among primary producers in terrestrial ecosystems, have attracted significant research attention. Leaf lifespan is an adaptive characteristic formed by plants to obtain the maximum carbon in the long-term adaption process. It determines important functional and structural characteristics exhibited in the environmental adaptation of plants. However, the leaf lifespan and leaf characteristics of urban forests were not studied up to now. By using statistic, linear regression methods and correlation analysis, leaf phenological characters of main tree species in urban forest of Shenyang were observed for five years to obtain the leafing phenology (including leafing start time, end time, and duration), defoliating phenology (including defoliation start time, end time, and duration), and the leaf lifespan of the main tree species. Moreover, the relationships between temperature and leafing phenology, defoliating phenology, and leaf lifespan were analyzed. The timing of leafing differed greatly among species. The early leafing species would have relatively early end of leafing; the longer it took to the end of leafing would have a later time of completed leafing. The timing of defoliation among different species varied significantly, the early defoliation species would have relatively longer duration of defoliation. If the mean temperature rise for 1°C in spring, the time of leafing would experience 5 days earlier in spring. If the mean temperature decline for 1°C, the time of defoliation would experience 3 days delay in autumn. There is significant correlation between leaf longevity and the time of leafing and defoliation. According to correlation analysis and regression analysis, there is significant correlation between temperature and leafing and defoliation phenology. Early leafing species would have a longer life span and consequently have advantage on carbon accumulation compared with later defoliation species.

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

NASA Astrophysics Data System (ADS)

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

2012-04-01

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 following trees: crabapple, horse chestnut, honey locust and hawthorn. These species constitute ~65% of the insect-pollinated fraction of the flowering tree canopy (excluding catkin-producing trees) from the total street area managed by the City of Boulder. Samples were subsequently 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 were found to increase 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 vegetative state for crabapple and honey locust. Total normalized (30oC) monoterpene emissions from honey locust were 4.3 fold higher during flowering (5.26 μgC g-1h-1) than after flowering (1.23 μgC g-1h-1). The total normalized BVOC emission rate from crabapple (93 μgC g-1h-1) during the flowering period is of the same order as isoprene emissions from oak trees, which are among the highest BVOC emissions observed to date. These findings illustrate that during the relatively brief springtime flowering period, floral emissions constitute by far the most significant contribution to the BVOC flux from these tree species, some of which are leafless at this time. These experimental results were integrated into the MEGAN biogenic emission model and simulations were performed to estimate the contribution of floral BVOC emissions to the total urban BVOC flux during the spring flowering period. The floral BVOC emitted during this three-month simulation constitute eleven percent of the cumulative monoterpene flux for the Boulder urban area.

Analyzing lead concentration in the sycamore tree species in high- and low-traffic areas of Rasht, Iran.

PubMed

Hashemi, Seyed Armin; Alinejad, Farzaneh; FallahChay, Mozaffar

2015-06-01

Important heavy metals such as lead and cadmium are part of the pollutants produced by cars and are spread in the urban environment by traffic flow. In order to study the amount of contamination in the trees along the streets and to determine the traffic parameters that affect the lead content in sycamore leaves in Rasht, four stations on the margins of the city streets were selected for this case study in terms of traffic volume (low or high). Traffic parameters including three high-traffic stations considering daily and monthly traffic volumes and one low-traffic station were selected. First, 32 sycamore bases were randomly chosen at the intervals of 10-15 m from the whole range of tree canopy in order to determine the absorption of lead; and then, 20 g of each sample were tested to determine the amount of lead absorption. The results of this study, on the amount of lead absorption by the sycamore tree species at three high-traffic and one control station, showed that Takhti station had the highest amount of lead absorption (37.19 ppm) compared with other three stations. Therefore, the sycamore tree species can be an appropriate one for the margins of urban streets. © The Author(s) 2013.

Light pollution is associated with earlier tree budburst across the United Kingdom.

PubMed

Ffrench-Constant, Richard H; Somers-Yeates, Robin; Bennie, Jonathan; Economou, Theodoros; Hodgson, David; Spalding, Adrian; McGregor, Peter K

2016-06-29

The ecological impact of night-time lighting is of concern because of its well-demonstrated effects on animal behaviour. However, the potential of light pollution to change plant phenology and its corresponding knock-on effects on associated herbivores are less clear. Here, we test if artificial lighting can advance the timing of budburst in trees. We took a UK-wide 13 year dataset of spatially referenced budburst data from four deciduous tree species and matched it with both satellite imagery of night-time lighting and average spring temperature. We find that budburst occurs up to 7.5 days earlier in brighter areas, with the relationship being more pronounced for later-budding species. Excluding large urban areas from the analysis showed an even more pronounced advance of budburst, confirming that the urban 'heat-island' effect is not the sole cause of earlier urban budburst. Similarly, the advance in budburst across all sites is too large to be explained by increases in temperature alone. This dramatic advance of budburst illustrates the need for further experimental investigation into the impact of artificial night-time lighting on plant phenology and subsequent species interactions. As light pollution is a growing global phenomenon, the findings of this study are likely to be applicable to a wide range of species interactions across the world. © 2016 The Authors.

Comparison of methods for estimating carbon dioxide storage by Sacramento's urban forest

Treesearch

Elena Aguaron; E. Gregory McPherson

2012-01-01

Limited open-grown urban tree species biomass equations have necessitated use of forest-derived equations with diverse conclusions on the accuracy of these equations to estimate urban biomass and carbon storage. Our goal was to determine and explain variability among estimates of CO2 storage from four sets of allometric equations for the same...

The ecology, distribution, conservation and management of large old trees.

PubMed

Lindenmayer, David B; Laurance, William F

2017-08-01

Large old trees are some of the most iconic biota on earth and are integral parts of many terrestrial ecosystems including those in tropical, temperate and boreal forests, deserts, savannas, agro-ecological areas, and urban environments. In this review, we provide new insights into the ecology, function, evolution and management of large old trees through broad cross-disciplinary perspectives from literatures in plant physiology, growth and development, evolution, habitat value for fauna and flora, and conservation management. Our review reveals that the diameter, height and longevity of large old trees varies greatly on an inter-specific basis, thereby creating serious challenges in defining large old trees and demanding an ecosystem- and species-specific definition that will only rarely be readily transferable to other species or ecosystems. Such variation is also manifested by marked inter-specific differences in the key attributes of large old trees (beyond diameter and height) such as the extent of buttressing, canopy architecture, the extent of bark micro-environments and the prevalence of cavities. We found that large old trees play an extraordinary range of critical ecological roles including in hydrological regimes, nutrient cycles and numerous ecosystem processes. Large old trees strongly influence the spatial and temporal distribution and abundance of individuals of the same species and populations of numerous other plant and animal species. We suggest many key characteristics of large old trees such as extreme height, prolonged lifespans, and the presence of cavities - which confer competitive and evolutionary advantages in undisturbed environments - can render such trees highly susceptible to a range of human influences. Large old trees are vulnerable to threats ranging from droughts, fire, pests and pathogens, to logging, land clearing, landscape fragmentation and climate change. Tackling such diverse threats is challenging because they often interact and manifest in different ways in different ecosystems, demanding targeted species- or ecosystem-specific responses. We argue that novel management actions will often be required to protect existing large old trees and ensure the recruitment of new cohorts of such trees. For example, fine-scale tree-level conservation such as buffering individual stems will be required in many environments such as in agricultural areas and urban environments. Landscape-level approaches like protecting places where large old trees are most likely to occur will be needed. However, this brings challenges associated with likely changes in tree distributions associated with climate change, because long-lived trees may presently exist in places unsuitable for the development of new cohorts of the same species. Appropriate future environmental domains for a species could exist in new locations where it has never previously occurred. The future distribution and persistence of large old trees may require controversial responses including assisted migration via seed or seedling establishment in new locales. However, the effectiveness of such approaches may be limited where key ecological features of large old trees (such as cavity presence) depend on other species such as termites, fungi and bacteria. Unless other species with similar ecological roles are present to fulfil these functions, these taxa might need to be moved concurrently with the target tree species. © 2016 Cambridge Philosophical Society.

Co-occurrence Patterns of the Dengue Vector Aedes aegypti and Aedes mediovitattus, a Dengue Competent Mosquito in Puerto Rico

PubMed Central

Little, Eliza; Barrera, Roberto; Seto, Karen C.; Diuk-Wasser, Maria

2015-01-01

Aedes aegypti is implicated in dengue transmission in tropical and subtropical urban areas around the world. Ae. aegypti populations are controlled through integrative vector management. However, the efficacy of vector control may be undermined by the presence of alternative, competent species. In Puerto Rico, a native mosquito, Ae. mediovittatus, is a competent dengue vector in laboratory settings and spatially overlaps with Ae. aegypti. It has been proposed that Ae. mediovittatus may act as a dengue reservoir during inter-epidemic periods, perpetuating endemic dengue transmission in rural Puerto Rico. Dengue transmission dynamics may therefore be influenced by the spatial overlap of Ae. mediovittatus, Ae. aegypti, dengue viruses, and humans. We take a landscape epidemiology approach to examine the association between landscape composition and configuration and the distribution of each of these Aedes species and their co-occurrence. We used remotely sensed imagery from a newly launched satellite to map landscape features at very high spatial resolution. We found that the distribution of Ae. aegypti is positively predicted by urban density and by the number of tree patches, Ae. mediovittatus is positively predicted by the number of tree patches, but negatively predicted by large contiguous urban areas, and both species are predicted by urban density and the number of tree patches. This analysis provides evidence that landscape composition and configuration is a surrogate for mosquito community composition, and suggests that mapping landscape structure can be used to inform vector control efforts as well as to inform urban planning. PMID:21989642

Ectomycorrhizal Fungal Communities in Urban Parks Are Similar to Those in Natural Forests but Shaped by Vegetation and Park Age

PubMed Central

Liu, Xinxin; Kotze, D. Johan; Jumpponen, Ari; Francini, Gaia; Setälä, Heikki

2017-01-01

ABSTRACT Ectomycorrhizal (ECM) fungi are important mutualists for the growth and health of most boreal trees. Forest age and its host species composition can impact the composition of ECM fungal communities. Although plentiful empirical data exist for forested environments, the effects of established vegetation and its successional trajectories on ECM fungi in urban greenspaces remain poorly understood. We analyzed ECM fungi in 5 control forests and 41 urban parks of two plant functional groups (conifer and broadleaf trees) and in three age categories (10, ∼50, and >100 years old) in southern Finland. Our results show that although ECM fungal richness was marginally greater in forests than in urban parks, urban parks still hosted rich and diverse ECM fungal communities. ECM fungal community composition differed between the two habitats but was driven by taxon rank order reordering, as key ECM fungal taxa remained largely the same. In parks, the ECM communities differed between conifer and broadleaf trees. The successional trajectories of ECM fungi, as inferred in relation to the time since park construction, differed among the conifers and broadleaf trees: the ECM fungal communities changed over time under the conifers, whereas communities under broadleaf trees provided no evidence for such age-related effects. Our data show that plant-ECM fungus interactions in urban parks, in spite of being constructed environments, are surprisingly similar in richness to those in natural forests. This suggests that the presence of host trees, rather than soil characteristics or even disturbance regime of the system, determine ECM fungal community structure and diversity. IMPORTANCE In urban environments, soil and trees improve environmental quality and provide essential ecosystem services. ECM fungi enhance plant growth and performance, increasing plant nutrient acquisition and protecting plants against toxic compounds. Recent evidence indicates that soil-inhabiting fungal communities, including ECM and saprotrophic fungi, in urban parks are affected by plant functional type and park age. However, ECM fungal diversity and its responses to urban stress, plant functional type, or park age remain unknown. The significance of our study is in identifying, in greater detail, the responses of ECM fungi in the rhizospheres of conifer and broadleaf trees in urban parks. This will greatly enhance our knowledge of ECM fungal communities under urban stresses, and the findings can be utilized by urban planners to improve urban ecosystem services. PMID:28970220

Optimising UK urban road verge contributions to biodiversity and ecosystem services with cost-effective management.

PubMed

O'Sullivan, Odhran S; Holt, Alison R; Warren, Philip H; Evans, Karl L

2017-04-15

Urban road verges can contain significant biodiversity, contribute to structural connectivity between other urban greenspaces, and due to their proximity to road traffic are well placed to provide ecosystem services. Using the UK as a case study we review and critically evaluate a broad range of evidence to assess how this considerable potential can be enhanced despite financial, contractual and public opinion constraints. Reduced mowing frequency and other alterations would enhance biodiversity, aesthetics and pollination services, whilst delivering costs savings and potentially being publically acceptable. Retaining mature trees and planting additional ones is favourable to residents and would enhance biodiversity, pollution and climate regulation, carbon storage, and stormwater management. Optimising these services requires improved selection of tree species, and creating a more diverse tree stock. Due to establishment costs additional tree planting and maintenance could benefit from payment for ecosystem service schemes. Verges could also provide areas for cultivation of biofuels and possibly food production. Maximising the contribution of verges to urban biodiversity and ecosystem services is economical and becoming an increasingly urgent priority as the road network expands and other urban greenspace is lost, requiring enhancement of existing greenspace to facilitate sustainable urban development. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Institute of forest tree breeding: Improvement and gene conservation of iconic tree species in the 21st Century

Treesearch

C. Dana Nelson; Jennifer L. Koch

2017-01-01

Our nation’s forests and forest trees are undergoing unprecedented stress from invasive pathogens and pests, climate change, land fragmentation, and urbanization. Some of these stresses are acute, either regionally or locally, and are having significant negative impacts on regional and local economies and ecosystems. Managing and improving the genetic resources of...

Ultraviolet leaf reflectance of common urban trees and the prediction of reflectance from leaf surface characteristics

Treesearch

Richard H. Grant; Gordon M. Heisler; Wei Gao; Matthew Jenks

2003-01-01

The spectral reflectance and transmittance over the wavelength range of 250-700nm were evaluated for leaves of 20 deciduous tree species and leaf sheaths of five isogenic wax variants of Sorghum bicolor differing in visible reflectance due to cuticular waxes. Using the sorghum sheath reflectance and cuticle surface characteristics as a model, it was concluded that tree...

Shade factors for 149 taxa of in-leaf urban trees in the USA

Treesearch

E. Gregory McPherson; Qingfu Xiao; Natalie S. van Doorn; Nels Johnson; Shannon Albers; Paula J. Peper

2018-01-01

Shade factors, defined as the percentage of sky covered by foliage and branches within the perimeter of individual tree crowns, have been used to model the effects of trees on air pollutant uptake, building energy use and rainfall interception. For the past 30 years the primary source of shade factors was a database containing values from 47 species. In most...

Analysis of the effect of evergreen and deciduous trees on urban nitrogen dioxide levels in the U.S. using land-use regression

NASA Astrophysics Data System (ADS)

Rao, M.; George, L. A.

2012-12-01

Nitrogen dioxide (NO2), an atmospheric pollutant generated primarily by anthropogenic combustion processes, is typically found at higher concentrations in urban areas compared to non-urbanized environments. Elevated NO2 levels have multiple ecosystem effects at different spatial scales. At the local scale, elevated levels affect human health directly and through the formation of secondary pollutants such as ozone and aerosols; at the regional scale secondary pollutants such as nitric acid and organic nitrates have deleterious effects on non-urbanized areas; and, at the global scale, nitrogen oxide emissions significantly alter the natural biogeochemical nitrogen cycle. As cities globally become larger and larger sources of nitrogen oxide emissions, it is important to assess possible mitigation strategies to reduce the impact of emissions locally, regionally and globally. In this study, we build a national land-use regression (LUR) model to compare the impacts of deciduous and evergreen trees on urban NO2 levels in the United States. We use the EPA monitoring network values of NO2 levels for 2006, the 2006 NLCD tree canopy data for deciduous and evergreen canopies, and the US Census Bureau's TIGER shapefiles for roads, railroads, impervious area & population density as proxies for NO2 sources on-road traffic, railroad traffic, off-road and area sources respectively. Our preliminary LUR model corroborates previous LUR studies showing that the presence of trees is associated with reduced urban NO2 levels. Additionally, our model indicates that deciduous and evergreen trees reduce NO2 to different extents, and that the amount of NO2 reduced varies seasonally. The model indicates that every square kilometer of deciduous canopy within a 2km buffer is associated with a reduction in ambient NO2 levels of 0.64 ppb in summer and 0.46ppb in winter. Similarly, every square kilometer of evergreen tree canopy within a 2 km buffer is associated with a reduction in ambient NO2 by 0.53 ppb in summer and 0.84 ppb in winter. Thus, the model indicates that deciduous trees are associated with a 30% smaller reduction in NO2 in winter as compared to summer, while evergreens are associated with a 60% increase in the reduction of NO2 in winter, for every square kilometer of deciduous or evergreen canopy within a 2 km buffer. Leaf- and local canopy-level studies have shown that trees are a sink for urban NO2 through deposition as well as stomatal and cuticular uptake. The winter time versus summer time effects suggest that leaf-level deposition may not be the only uptake mechanism and points to the need for a more holistic analysis of tree and canopy-level deposition for urban air pollution models. Since deposition velocities for NO2 vary by tree species, the reduction may also vary by species. These findings have implications for designing cities to reduce the impact of air pollution.

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

PubMed

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 especially SRC, which has high biomass production potential. For urban greenspace management, we recommend that planting SRC in urban areas can contribute to reducing food-fuel conflicts on agricultural land and produce renewable energy sources close to centres of population and demand.

Urban activities influence on Phytophthora species diversity in British Columbia, Canada

Treesearch

Angela Dale; Nicolas Feau; Julien Ponchart; Guillaume Bilodeau; Jean Berube; R.C. Hamelin

2017-01-01

Phytophthora de Bary, a genus of Oomycetes, is known as a plant pathogenic genus. The best-known species infect a wide range of hosts, including economically valuable angiosperm and gymnosperm tree species and important agricultural crops. Many Phytophthora are invasive and have been disseminated through nursery and...

Automatic tree parameter extraction by a Mobile LiDAR System in an urban context.

PubMed

Herrero-Huerta, Mónica; Lindenbergh, Roderik; Rodríguez-Gonzálvez, Pablo

2018-01-01

In an urban context, tree data are used in city planning, in locating hazardous trees and in environmental monitoring. This study focuses on developing an innovative methodology to automatically estimate the most relevant individual structural parameters of urban trees sampled by a Mobile LiDAR System at city level. These parameters include the Diameter at Breast Height (DBH), which was estimated by circle fitting of the points belonging to different height bins using RANSAC. In the case of non-circular trees, DBH is calculated by the maximum distance between extreme points. Tree sizes were extracted through a connectivity analysis. Crown Base Height, defined as the length until the bottom of the live crown, was calculated by voxelization techniques. For estimating Canopy Volume, procedures of mesh generation and α-shape methods were implemented. Also, tree location coordinates were obtained by means of Principal Component Analysis. The workflow has been validated on 29 trees of different species sampling a stretch of road 750 m long in Delft (The Netherlands) and tested on a larger dataset containing 58 individual trees. The validation was done against field measurements. DBH parameter had a correlation R2 value of 0.92 for the height bin of 20 cm which provided the best results. Moreover, the influence of the number of points used for DBH estimation, considering different height bins, was investigated. The assessment of the other inventory parameters yield correlation coefficients higher than 0.91. The quality of the results confirms the feasibility of the proposed methodology, providing scalability to a comprehensive analysis of urban trees.

Automatic tree parameter extraction by a Mobile LiDAR System in an urban context

PubMed Central

Lindenbergh, Roderik; Rodríguez-Gonzálvez, Pablo

2018-01-01

In an urban context, tree data are used in city planning, in locating hazardous trees and in environmental monitoring. This study focuses on developing an innovative methodology to automatically estimate the most relevant individual structural parameters of urban trees sampled by a Mobile LiDAR System at city level. These parameters include the Diameter at Breast Height (DBH), which was estimated by circle fitting of the points belonging to different height bins using RANSAC. In the case of non-circular trees, DBH is calculated by the maximum distance between extreme points. Tree sizes were extracted through a connectivity analysis. Crown Base Height, defined as the length until the bottom of the live crown, was calculated by voxelization techniques. For estimating Canopy Volume, procedures of mesh generation and α-shape methods were implemented. Also, tree location coordinates were obtained by means of Principal Component Analysis. The workflow has been validated on 29 trees of different species sampling a stretch of road 750 m long in Delft (The Netherlands) and tested on a larger dataset containing 58 individual trees. The validation was done against field measurements. DBH parameter had a correlation R2 value of 0.92 for the height bin of 20 cm which provided the best results. Moreover, the influence of the number of points used for DBH estimation, considering different height bins, was investigated. The assessment of the other inventory parameters yield correlation coefficients higher than 0.91. The quality of the results confirms the feasibility of the proposed methodology, providing scalability to a comprehensive analysis of urban trees. PMID:29689076

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

NASA Astrophysics Data System (ADS)

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 order as isoprene emissions from oak trees, which are among the highest BVOC flowering period floral emissions observed from plants to date. These findings illustrate that during the relatively brief springtime flowering period, floral emissions constitute by far the most significant contribution to the BVOC flux from these tree species, some of which are leafless at this time. Experimental results were integrated into the MEGAN biogenic emission model and simulations were performed to estimate the contribution of floral BVOC emissions to the total urban BVOC flux during the spring flowering period. The floral BVOC emitted during this three-month simulation are equivalent to 11% of the integrated monoterpene flux for the Boulder urban area.

Transpiration and root development of urban trees in structural soil stormwater reservoirs.

PubMed

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

2009-10-01

Stormwater management that relies on ecosystem processes, such as tree canopy interception and rhizosphere biology, can be difficult to achieve in built environments because urban land is costly and urban soil inhospitable to vegetation. Yet such systems offer a potentially valuable tool for achieving both sustainable urban forests and stormwater management. We evaluated tree water uptake and root distribution in a novel stormwater mitigation facility that integrates trees directly into detention reservoirs under pavement. The system relies on structural soils: highly porous engineered mixes designed to support tree root growth and pavement. To evaluate tree performance under the peculiar conditions of such a stormwater detention reservoir (i.e., periodically inundated), we grew green ash (Fraxinus pennsylvanica Marsh.) and swamp white oak (Quercus bicolor Willd.) in either CUSoil or a Carolina Stalite-based mix subjected to three simulated below-system infiltration rates for two growing seasons. Infiltration rate affected both transpiration and rooting depth. In a factorial experiment with ash, rooting depth always increased with infiltration rate for Stalite, but this relation was less consistent for CUSoil. Slow-drainage rates reduced transpiration and restricted rooting depth for both species and soils, and trunk growth was restricted for oak, which grew the most in moderate infiltration. Transpiration rates under slow infiltration were 55% (oak) and 70% (ash) of the most rapidly transpiring treatment (moderate for oak and rapid for ash). We conclude this system is feasible and provides another tool to address runoff that integrates the function of urban green spaces with other urban needs.

Remote sensing assessment of carbon storage by urban forest

NASA Astrophysics Data System (ADS)

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

2014-02-01

Urban forests play a crucial role in mitigating global warming by absorbing excessive CO2 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 (R2 = 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.

Leaf reflectance variation along a vertical crown gradient of two deciduous tree species in a Belgian industrial habitat.

PubMed

Khavaninzadeh, Ali Reza; Veroustraete, Frank; Van Wittenberghe, Shari; Verrelst, Jochem; Samson, Roeland

2015-09-01

The reflectometry of leaf asymmetry is a novel approach in the bio-monitoring of tree health in urban or industrial habitats. Leaf asymmetry responds to the degree of environmental pollution and reflects structural changes in a leaf due to environmental pollution. This paper describes the boundary conditions to scale up from leaf to canopy level reflectance, by describing the variability of adaxial and abaxial leaf reflectance, hence leaf asymmetry, along the crown height gradients of two tree species. Our findings open a research pathway towards bio-monitoring based on the airborne remote sensing of tree canopies and their leaf asymmetric properties. Copyright © 2015 Elsevier Ltd. All rights reserved.

Grand Forks - East Grand Forks Urban Water Resources Study. Social and Environmental Inventory.

DTIC Science & Technology

1979-01-01

61 Introduction 57IPrehistoric 58 Historic 58-61 Social Organization 62-72 Introduction 62 Demography 62-63 Population Distribution by Age 64-65 Urban...programs, native timber is decreasing due to agricultural clearing operatings and urban growth. Native tree species are important because of their longevity ... Demography 62-63 Population Distribution by Age 64-65 Urban-Rural Distribution 66 Population Projections 67-68 Racial Distribution 69 Ethnic Groups 70

Nest-site competition and killing by invasive parakeets cause the decline of a threatened bat population

PubMed Central

Carrete, Martina; Ibáñez, Carlos; Juste, Javier; Tella, José L.

2018-01-01

The identification of effects of invasive species is challenging owing to their multifaceted impacts on native biota. Negative impacts are most often reflected in individual fitness rather than in population dynamics of native species and are less expected in low-biodiversity habitats, such as urban environments. We report the long-term effects of invasive rose-ringed parakeets on the largest known population of a threatened bat species, the greater noctule, located in an urban park. Both species share preferences for the same tree cavities for breeding. While the number of parakeet nests increased by a factor of 20 in 14 years, the number of trees occupied by noctules declined by 81%. Parakeets occupied most cavities previously used by noctules, and spatial analyses showed that noctules tried to avoid cavities close to parakeets. Parakeets were highly aggressive towards noctules, trying to occupy their cavities, often resulting in noctule death. This led to a dramatic population decline, but also an unusual aggregation of the occupied trees, probably disrupting the complex social behaviour of this bat species. These results indicate a strong impact through site displacement and killing of competitors, and highlight the need for long-term research to identify unexpected impacts that would otherwise be overlooked. PMID:29892437

[Study of sand flies (Diptera, Psychodidae, Phlebotominae) in the urban area of Campo Grande, Mato Grosso do Sul State, Brazil, from 1999 to 2000].

PubMed

de Oliveira, Alessandra Gutierrez; Andrade Filho, José Dilermando; Falcão, Alda Lima; Brazil, Reginaldo Peçanha

2003-01-01

From February 1999 to February 2000, sand flies were captured weekly with CDC light traps at five sites in the urban area of Campo Grande, Mato Grosso do Sul State, Brazil. Traps were placed in 11 different ecotopes in the environment (ground level, tree canopies, and forest edge) and the peridomicile (chicken coops and banana trees). A total of 1,245 sand flies were captured, belonging to 28 species: 4 species from genus Brumptomyia Fran a & Parrot, 1921 and 24 from genus Lutzomyia Fran a, 1924. The species were: B. avellari, B. brumpti, B. galindoi, B. pintoi, L. aragaoi, L. bourrouli, L. campograndensis, L. cerradincola, L. christenseni, L. claustrei, L. cortelezzii, L. corumbaensis, L. cruzi, L. damascenoi, L. flaviscutellata, L. hermanlenti, L. lenti, L. longipalpis, L. longipennis, L. migonei, L. punctigeniculata, L. quinquefer, L. renei, L. shannoni, L. sordellii, L. teratodes, L. termitophila, and L. whitmani. L. longipalpis and L. cruzi, vectors of visceral leishmaniasis, and L. whitmani, L. flaviscutellata and L. migonei, vectors of cutaneous leishmaniasis, were captured in the urban area. The most frequent species were L. termitophila, L. aragaoi, L. lenti, L. longipennis, and L. longipalpis.

Study on the Adsorption Capacities for Airborne Particulates of Landscape Plants in Different Polluted Regions in Beijing (China)

PubMed Central

Zhang, Wei-Kang; Wang, Bing; Niu, Xiang

2015-01-01

Urban landscape plants are an important component of the urban ecosystem, playing a significant role in the adsorption of airborne particulates and air purification. In this study, six common landscape plants in Beijing were chosen as research subjects, and the adsorption capacities for each different plant leaf and the effects of the leaf structures for the adsorption capacities for particulates were determined. Preliminary results show that needle-leaved tree species adsorbed more airborne particulates than broad-leaved tree species for the same leaf area. Pinus tabuliformis exhibits the highest adsorption capacity, at 3.89 ± 0.026 μg·cm−2, almost two times as much as that of Populus tomentosa (2.00 ± 0.118 μg·cm−2). The adsorption capacities for PM10 of the same tree species leaves, in different polluted regions had significant differences, and the adsorption capacities for PM10 of the tree species leaf beside the Fifth Ring Road were higher than those of the tree species leaves in the Botanical Garden, although the adsorption capacities for PM2.5 of the same tree species in different polluted regions had no significant differences. By determining the soluble ion concentrations of the airborne particulates in two regions, it is suggested that the soluble ion concentrations of PM10 in the atmosphere in the Botanical Garden and beside the Fifth Ring Road have significant differences, while those of PM2.5 in the atmosphere had no significant differences. In different polluted regions there are significant adaptive changes to the leaf structures, and when compared with slightly polluted region, in the seriously polluted region the epidermis cells of the plant leaves shrinked, the surface textures of the leaves became rougher, and the stomas’ frequency and the pubescence length increased. Even though the plant leaves exposed to the seriously polluted region changed significantly, these plants can still grow normally and healthily. PMID:26287227

Integration of ecological indices in the multivariate evaluation of an urban inventory of street trees

Treesearch

J. Grabinsky; A. Aldama; A. Chacalo; H. J. Vazquez

2000-01-01

Inventory data of Mexico City's street trees were studied using classical statistical arboricultural and ecological statistical approaches. Multivariate techniques were applied to both. Results did not differ substantially and were complementary. It was possible to reduce inventory data and to group species, boroughs, blocks, and variables.

Geometric Modelling of Tree Roots with Different Levels of Detail

NASA Astrophysics Data System (ADS)

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.

Modeling urban host tree distributions for invasive forest insects using a two-step approach

Treesearch

Mark J. Ambrose; Frank H. Koch; Denys Yemshanov; P. Eric Wiseman

2015-01-01

Many alien insect species currently impacting forested ecosystems in North America first appeared in urban forests. Unfortunately, despite serving as critical gateways for the human-mediated spread of these and other forest pests, urban forests remain less well documented than their “natural” forest counterparts. While Forest Inventory and Analysis (FIA) data provide...

Ectomycorrhizal Fungal Communities in Urban Parks Are Similar to Those in Natural Forests but Shaped by Vegetation and Park Age.

PubMed

Hui, Nan; Liu, Xinxin; Kotze, D Johan; Jumpponen, Ari; Francini, Gaia; Setälä, Heikki

2017-12-01

Ectomycorrhizal (ECM) fungi are important mutualists for the growth and health of most boreal trees. Forest age and its host species composition can impact the composition of ECM fungal communities. Although plentiful empirical data exist for forested environments, the effects of established vegetation and its successional trajectories on ECM fungi in urban greenspaces remain poorly understood. We analyzed ECM fungi in 5 control forests and 41 urban parks of two plant functional groups (conifer and broadleaf trees) and in three age categories (10, ∼50, and >100 years old) in southern Finland. Our results show that although ECM fungal richness was marginally greater in forests than in urban parks, urban parks still hosted rich and diverse ECM fungal communities. ECM fungal community composition differed between the two habitats but was driven by taxon rank order reordering, as key ECM fungal taxa remained largely the same. In parks, the ECM communities differed between conifer and broadleaf trees. The successional trajectories of ECM fungi, as inferred in relation to the time since park construction, differed among the conifers and broadleaf trees: the ECM fungal communities changed over time under the conifers, whereas communities under broadleaf trees provided no evidence for such age-related effects. Our data show that plant-ECM fungus interactions in urban parks, in spite of being constructed environments, are surprisingly similar in richness to those in natural forests. This suggests that the presence of host trees, rather than soil characteristics or even disturbance regime of the system, determine ECM fungal community structure and diversity. IMPORTANCE In urban environments, soil and trees improve environmental quality and provide essential ecosystem services. ECM fungi enhance plant growth and performance, increasing plant nutrient acquisition and protecting plants against toxic compounds. Recent evidence indicates that soil-inhabiting fungal communities, including ECM and saprotrophic fungi, in urban parks are affected by plant functional type and park age. However, ECM fungal diversity and its responses to urban stress, plant functional type, or park age remain unknown. The significance of our study is in identifying, in greater detail, the responses of ECM fungi in the rhizospheres of conifer and broadleaf trees in urban parks. This will greatly enhance our knowledge of ECM fungal communities under urban stresses, and the findings can be utilized by urban planners to improve urban ecosystem services. Copyright © 2017 American Society for Microbiology.

Exotic weeds and fluctuating microclimate can constrain native plant regeneration in urban forest restoration.

PubMed

Wallace, K J; Laughlin, Daniel C; Clarkson, Bruce D

2017-06-01

Restoring forest structure and composition is an important component of urban land management, but we lack clear understanding of the mechanisms driving restoration success. Here we studied two indicators of restoration success in temperate rainforests: native tree regeneration and epiphyte colonization. We hypothesized that ecosystem properties such as forest canopy openness, abundance of exotic herbaceous weeds, and the microclimate directly affect the density and diversity of native tree seedlings and epiphytes. Relationships between environmental conditions and the plant community were investigated in 27 restored urban forests spanning 3-70 years in age and in unrestored and remnant urban forests. We used structural equation modelling to determine the direct and indirect drivers of native tree regeneration and epiphyte colonization in the restored forests. Compared to remnant forest, unrestored forest had fewer native canopy tree species, significantly more light reaching the forest floor annually, and higher exotic weed cover. Additionally, epiphyte density was lower and native tree regeneration density was marginally lower in the unrestored forests. In restored forests, light availability was reduced to levels found in remnant forests within 20 years of restoration planting, followed shortly thereafter by declines in herbaceous exotic weeds and reduced fluctuation of relative humidity and soil temperatures. Contrary to expectations, canopy openness was only an indirect driver of tree regeneration and epiphyte colonization, but it directly regulated weed cover and microclimatic fluctuations, both of which directly drove the density and richness of regeneration and epiphyte colonization. Epiphyte density and diversity were also positively related to forest basal area, as large trees provide physical habitat for colonization. These results imply that ecosystem properties change predictably after initial restoration plantings, and that reaching critical thresholds in some ecosystem properties makes conditions suitable for the regeneration of late successional species, which is vital for restoration success and long-term ecosystem sustainability. Abiotic and biotic conditions that promote tree regeneration and epiphyte colonization will likely be present in forests with a basal area ≥27 m 2 /ha. We recommend that urban forest restoration plantings be designed to promote rapid canopy closure to reduce light availability, suppress herbaceous weeds, and stabilize the microclimate. © 2017 by the Ecological Society of America.

[Effects of reforestation on tree pollen sensitization in inhabitants of Nuevo Leon, Mexico].

PubMed

Palma-Gómez, Samuel; González-Díaz, Sandra Nora; Arias-Cruz, Alfredo; Macías-Weinmann, Alejandra; Amaro-Vivian, Laura Elizabeth; Pérez-Vanzzini, Rafael; Gutiérrez-Mujica, José Julio; Yong-Rodríguez, Adrián

2014-01-01

Climate change has implications for health, ecology and society. Urban green areas are a key element in the planning of cities, promoting citizen interaction with the environment, as well as health. Lack of planning and design of these areas as well as the selection of ornamental trees can be a trigger of pollen allergy in the surrounding population. Reforestation is among the programs implemented by the government that have an impact on allergy. Environmental reforestation programs do not take into account the allergenic potential of some species. In the last 4 years, the government of Nuevo Leon, Mexico, has planted nearly 18,000 Quercus species trees, in addition to an unknown number of Fraxinus species trees that are listed as tree species with high pollen production. To identify changes in tree pollen sensitization, based on environmental reforestation programs. A retrospective and descriptive study was done in which positive skin prick tests to pollen from trees in the interval of 2010-2014 were analyzed, correlating between tree species used for reforestation and increased sensitivity to the former. A statistically significant increase in pollen sensitization to species with which Nuevo Leon was reforested was found, along with a decrease in sensitization to the species that were not reforested. Reforestation contributes to some extent to the change in the pattern of positive skin tests and may result in more frequent exacerbations of respiratory diseases. It is an activity that should always be regulated and assisted by experts in the according field.

Tree colonization by the Asian longhorn beetle, Anoplophora glabripennis (Coleoptera: Cerambycidae): effect of habitat and tree suitability.

PubMed

Faccoli, Massimo; Favaro, Riccardo; Concheri, Giuseppe; Squartini, Andrea; Battisti, Andrea

2016-04-01

Tree colonization and feeding activity of the invasive wood-borer Asian longhorn beetle (Anoplophora glabripennis), an Asian pest introduced into North America and Europe, was studied in a newly invaded area in Italy. The hypothesis being tested was that the reproductive success of the insect depend on habitat type and tree suitability. Adult beetles were caged on branches of host and nonhost species, in both urban and forest habitats. Two months later, number and size of feeding patches on plant tissues, eggs laid, and surviving larvae were assessed. Bark concentration of C and N was also measured from the same trees. Results indicated that the mean area of plant tissues consumed by adult feeding was significantly larger on trees growing in forest than in urban habitat, although within the same habitat there were no differences between susceptible and nonsusceptible trees. ALB tree colonization, in terms of number of eggs laid and young larvae survival, was not affected by habitat while it was higher on susceptible trees. Although trees growing in forests had a lower nitrogen concentration, they allowed colonization rates similar to those of trees growing in the urban habitat. Hence, the amount of carbon and nitrogen did not fully explain tree suitability or habitat selection. We suggest compensatory feeding as a potential mechanism that might explain this peculiar situation, as supported by a more intensive feeding activity recorded on trees in the forest. Suitability of different trees may be due to other factors, such as secondary chemical compounds. © 2014 Institute of Zoology, Chinese Academy of Sciences.

Economic analysis of emerald ash borer (Coleoptera: Buprestidae) management options.

PubMed

Vannatta, A R; Hauer, R H; Schuettpelz, N M

2012-02-01

Emerald ash borer, Agrilus planipennis (Fairmaire) (Coleoptera: Buprestidae), plays a significant role in the health and extent of management of native North American ash species in urban forests. An economic analysis of management options was performed to aid decision makers in preparing for likely future infestations. Separate ash tree population valuations were derived from the i-Tree Streets program and the Council of Tree and Landscape Appraisers (CTLA) methodology. A relative economic analysis was used to compare a control option (do-nothing approach, only removing ash trees as they die) to three distinct management options: 1) preemptive removal of all ash trees over a 5 yr period, 2) preemptive removal of all ash trees and replacement with comparable nonash trees, or 3) treating the entire population of ash trees with insecticides to minimize mortality. For each valuation and management option, an annual analysis was performed for both the remaining ash tree population and those lost to emerald ash borer. Retention of ash trees using insecticide treatments typically retained greater urban forest value, followed by doing nothing (control), which was better than preemptive removal and replacement. Preemptive removal without tree replacement, which was the least expensive management option, also provided the lowest net urban forest value over the 20-yr simulation. A "no emerald ash borer" scenario was modeled to further serve as a benchmark for each management option and provide a level of economic justification for regulatory programs aimed at slowing the movement of emerald ash borer.

Bioaccumulation of heavy metals in plant leaves from Yan׳an city of the Loess Plateau, China.

PubMed

Hu, Youning; Wang, Dexiang; Wei, Lijing; Zhang, Xinping; Song, Bin

2014-12-01

Urban plants are capable of reducing environmental pollutions through bioaccumulation contaminants in their tissues. The accumulation of heavy metals (Pb, Cu, Cd, Cr, and Zn) in leaves of nine tree species and five shrub species from Yan׳an city of China were investigated, and total metal accumulation capacities of different plants were evaluated using the metal accumulation index (MAI). The results indicated that plants in polluted environments are enriched in heavy metals relative to those in pristine environments, this is mainly caused by traffic emissions and coal combustion. Species with the highest accumulation of a single metal did not have the highest total metal accumulation capacity, the MAI should be an important indicator for tree species selection in phytoextraction and urban greening. Considering total accumulation capacities, Sabina chinensis, Juniperus formosana, Ailanthus altissima and Salix matsudana var. matsudana could be widely used in the Loess Plateau. Copyright © 2014 Elsevier Inc. All rights reserved.

A comparative study on capability of different tree species in accumulating heavy metals from soil and ambient air.

PubMed

Alahabadi, Ahmad; Ehrampoush, Mohammad Hassan; Miri, Mohammad; Ebrahimi Aval, Hamideh; Yousefzadeh, Samira; Ghaffari, Hamid Reza; Ahmadi, Ehsan; Talebi, Parvaneh; Abaszadeh Fathabadi, Zeynab; Babai, Fatemeh; Nikoonahad, Ali; Sharafi, Kiomars; Hosseini-Bandegharaei, Ahmad

2017-04-01

Heavy metals (HMs) in the urban environment can be bio-accumulated by plant tissues. The aim of this study was to compare fourteen different tree species in terms of their capability to accumulate four airborne and soilborne HMs including; zinc (Zn), copper (Cu), lead (Pb), and cadmium (Cd). Samplings were performed during spring, summer, and fall seasons. To compare bioaccumulation ability, bio-concentration factor (BCF), comprehensive bio-concentration index (CBCI), and metal accumulation index (MAI) were applied. Species with the highest accumulation for single metal which shown using BCF did not have the highest CBCI and MAI. Based on CBCI and MAI, Pinus eldarica (7.74), Wistaria sinensis (8.82), Morus alba (8.7), and Nigral morus (27.15) had the highest bioaccumulation capacity of HMs, respectively. Therefore, these species can be used for phytoextraction of HMs pollution and green and buffer zone in the urban. Copyright © 2017 Elsevier Ltd. All rights reserved.

Leaf Phenological Characters of Main Tree Species in Urban Forest of Shenyang

PubMed Central

Xu, Sheng; Xu, Wenduo; Chen, Wei; He, Xingyuan; Huang, Yanqing; Wen, Hua

2014-01-01

Background Plant leaves, as the main photosynthetic organs and the high energy converters among primary producers in terrestrial ecosystems, have attracted significant research attention. Leaf lifespan is an adaptive characteristic formed by plants to obtain the maximum carbon in the long-term adaption process. It determines important functional and structural characteristics exhibited in the environmental adaptation of plants. However, the leaf lifespan and leaf characteristics of urban forests were not studied up to now. Methods By using statistic, linear regression methods and correlation analysis, leaf phenological characters of main tree species in urban forest of Shenyang were observed for five years to obtain the leafing phenology (including leafing start time, end time, and duration), defoliating phenology (including defoliation start time, end time, and duration), and the leaf lifespan of the main tree species. Moreover, the relationships between temperature and leafing phenology, defoliating phenology, and leaf lifespan were analyzed. Findings The timing of leafing differed greatly among species. The early leafing species would have relatively early end of leafing; the longer it took to the end of leafing would have a later time of completed leafing. The timing of defoliation among different species varied significantly, the early defoliation species would have relatively longer duration of defoliation. If the mean temperature rise for 1°C in spring, the time of leafing would experience 5 days earlier in spring. If the mean temperature decline for 1°C, the time of defoliation would experience 3 days delay in autumn. Interpretation There is significant correlation between leaf longevity and the time of leafing and defoliation. According to correlation analysis and regression analysis, there is significant correlation between temperature and leafing and defoliation phenology. Early leafing species would have a longer life span and consequently have advantage on carbon accumulation compared with later defoliation species. PMID:24963625

Habitat and forage associations of a naturally colonising insect pollinator, the tree bumblebee Bombus hypnorum.

PubMed

Crowther, Liam P; Hein, Pierre-Louis; Bourke, Andrew F G

2014-01-01

Bumblebees (Bombus species) are major pollinators of commercial crops and wildflowers but factors affecting their abundance, including causes of recent population declines, remain unclear. Investigating the ecology of species with expanding ranges provides a potentially powerful means of elucidating these factors. Such species may also bring novel pollination services to their new ranges. We therefore investigated landscape-scale habitat use and foraging preferences of the Tree Bumblebee, B. hypnorum, a recent natural colonist that has rapidly expanded its range in the UK over the past decade. Counts of B. hypnorum and six other Bombus species were made in March-June 2012 within a mixed landscape in south-eastern Norfolk, UK. The extent of different landscape elements around each transect was quantified at three scales (250 m, 500 m and 1500 m). We then identified the landscape elements that best predicted the density of B. hypnorum and other Bombus species. At the best fitting scale (250 m), B. hypnorum density was significantly positively associated with extent of both urban and woodland cover and significantly negatively associated with extent of oilseed rape cover. This combination of landscape predictors was unique to B. hypnorum. Urban and woodland cover were associated with B. hypnorum density at three and two, respectively, of the three scales studied. Relative to other Bombus species, B. hypnorum exhibited a significantly higher foraging preference for two flowering trees, Crataegus monogyna and Prunus spinosa, and significantly lower preferences for Brassica napus, Glechoma hederacea and Lamium album. Our study provides novel, quantitative support for an association of B. hypnorum with urban and woodland landscape elements. Range expansion in B. hypnorum appears to depend, on exploitation of widespread habitats underutilised by native Bombus species, suggesting B. hypnorum will readily co-exist with these species. These findings suggest that management could target bumblebee species with distinctive habitat requirements to help maintain pollination services.

Spectral variability of deciduous leaves depending on the developmental stages and tree condition

NASA Astrophysics Data System (ADS)

Song, Y.; Ryu, Y.

2013-12-01

Foliar spectral characteristics could be the key information in modeling forest ecosystem and the remote sensing of vegetation identification. But it is not easy to determine a typical leaf spectrum of a species in a standardized state. That is because of variables critically influencing on the spectral property of leaves, such as inter- and intra-species features, phenological phase, or biotic and abiotic stress. In this study, we attempted to quantify the spectral variability of leaves depending on species, developmental stages, and the condition of trees. The contribution of these factors to the spectral variation was analyzed at the single leaf level, with a large number of samples from deciduous plants in the urban forested area. First, we collected tens of leaf-samples at every biweekly fieldwork in the growing season, for the selected 5 tree species popular in urban parks; Acer palmatum, Carpinus laxiflora, Prunus yedoensis, Quercus acutissima, and Zelkova serrata. And absorbance, reflectance and transmittance spectra of the leaves were acquired at the short-visible (400-700 nm) to infrared (700-2500 nm) spectral region with 1 nm interval. Seasonality in these leaf-spectra was used to understand the inter-species variation depending on developmental stages. Second, as a benchmark for testing intra-species variability and differences by tree condition, we additionally analyzed the spectral reflectance of 504 ripe leaves from 56 cherry trees (Cerasus × yedoensis) collected in the middle of summer. Last, using ANOVA (analysis of variance) and general linear model, we assessed the influence of our tested variables (i.e., species, developmental stage, and tree condition) on the spectral characteristics and their vegetation indices. As a result, we clarified that the changes in leaf-spectra was apparent across all the tested species during the growing season from May to June, indicating the increasing trend of absorbance in photosynthetically active radiation region (400 to 700 nm; PAR) and reflectance in the near infrared region (700 to 1300 nm; NIR). Inter-species variability still appeared substantial and those inherit spectral characteristics was difficult to be described in a single universal vegetation index. The reflectance values of leaves were significantly differed in good and poor tree condition, which could be the other important consideration in the representative scheme of leaf sampling. More discussions will be present about the effect of species, developmental stage, and tree condition to the leaf-spectra and the published vegetation indices.

Hydrocarbon emissions from twelve urban shade trees of the Los Angeles, California, Air Basin

NASA Astrophysics Data System (ADS)

Corchnoy, Stephanie B.; Arey, Janet; Atkinson, Roger

The large-scale planting of shade trees in urban areas to counteract heat-island effects and to minimize energy use is currently being discussed. Among the costs to be considered in a cost/benefit analysis of such a program is the potential for additional reactive organic compounds in the atmosphere due to emissions from these trees. In this program, 15 species of potential shade trees for the Los Angeles Air Basin were studied and emission rates were determined for 11 of these trees, with one further tree (Crape myrtle) exhibiting no detectable emissions. The emission rates normalized to dry leaf weight and corrected to 30°C were (in μg g -1 h -1), ranked from lowest to highest emission rate: Crape myrtle, none detected; Camphor, 0.03; Aleppo pine, 0.15; Deodar cedar, 0.29; Italian Stone pine, 0.42; Monterey pine, 0.90; Brazilian pepper, 1.3; Canary Island pine, 1.7; Ginkgo, 3.0; California pepper, 3.7; Liquidambar, 37; Carrotwood, 49. In addition to the emission rates per unit biomass, the biomass per tree must be factored into any assessment of the relative merits of the various trees, since some trees have higher biomass constants than others. The present data shows that there are large differences in emission rates among different tree species and this should be factored into decision-making as to which shade trees to plant. Based solely on the presently determined emission rates, the Crape myrtle and Camphor tree are good choices for large-scale planting, while the Carrotwood tree and Liquidambar are poor choices due to their high isoprene emission rates.

The role of CVS (and FIA) data and genetic tests in assessing species vulnerability to invasive pests and changing climate

Treesearch

R.A. Sniezko; H.E. Lintz

2017-01-01

United States tree species and their associated ecosystems, managed forests, and urban plantings are increasingly vulnerable to non-native invasive pathogens and insects as well as effects associated with a changing climate. Some species, such as whitebark pine (Pinus albicaulis), have been proposed for listing under the Endangered Species Act. To...

The Urban Ecology Institute's field studies program: utilizing urban areas for experiential learning and ecological research

NASA Astrophysics Data System (ADS)

Starry, O.

2005-05-01

The Urban Ecology Institute (UEI) promotes the stewardship of healthy urban ecosystems by improving science and civic education for middle and high school youth and by working with urban communities to protect and transform natural resources. Established in 1999, UEI's field studies program engages over 1000 youth in the greater Boston area. A substantial component of this program involves water quality monitoring. We have recently adapted protocols from published leaf breakdown studies for incorporation into the UEI water quality curriculum. A 2004 pilot study of these leaf breakdown activities, conducted at four sites, compared rates of red maple breakdown to those of Norway maple, a potentially invasive urban street tree. Preliminary data from this successful pilot study suggest that leaf litter inputs from the two different tree species have varying effects on stream ecosystem function. We present this study as an example of how urban areas can be utilized for both ecological research and inclusive experiential learning through which science and mathematic knowledge can be effectively communicated.

Evaluation of seven drought tolerant tree species for central California

Treesearch

E.G. McPherson; S. Albers

2014-01-01

Climate change poses challenges for the Southwest, where an already parched region is expected to get hotter and, in its southern half, significantly drier (Garfin et al. 2013). Increased heat and sustained drought will stress water sources and redefine urban landscapes. As landscapes gradually evolve from lush to xeric, tolerance of trees to water-related stress...

History and range of Norway maple

Treesearch

David J. Nowak; Rowan A. Rowntree

1990-01-01

The Norway maple, Acer platanoldes, was introduced into the United States about 1756 after being cultivated in England since 1683. This species remained in relative obscurity in the U.S. until the mid- to late-1800's, but is now one of the most popular urban trees. In certain regions of the United States, Norway maples dominate street tree...

Specialist nectar-yeasts decline with urbanization in Berlin

NASA Astrophysics Data System (ADS)

Wehner, Jeannine; Mittelbach, Moritz; Rillig, Matthias C.; Verbruggen, Erik

2017-03-01

Nectar yeasts are common inhabitants of insect-pollinated flowers but factors determining their distribution are not well understood. We studied the influence of host identity, environmental factors related to pollution/urbanization, and the distance to a target beehive on local distribution of nectar yeasts within Robinia pseudoacacia L. and Tilia tomentosa Moench in Berlin, Germany. Nectar samples of six individuals per species were collected at seven sites in a 2 km radius from each target beehive and plated on YM-Agar to visualise the different morphotypes, which were then identified by sequencing a section of the 26S rDNA gene. Multivariate linear models were used to analyze the effects of all investigated factors on yeast occurrence per tree. Yeast distribution was mainly driven by host identity. The influence of the environmental factors (NO2, height of construction, soil sealing) strongly depended on the radius around the tree, similar to the distance of the sampled beehive. Incidence of specialist nectar-borne yeast species decreased with increasing pollution/urbanization index. Given that specialist yeast species gave way to generalist yeasts that have a reduced dependency on pollinators for between-flower dispersal, our results indicate that increased urbanization may restrict the movement of nectar-specialized yeasts, via limitations of pollinator foraging behavior.

Developing a Method to Mask Trees in Commercial Multispectral Imagery

NASA Astrophysics Data System (ADS)

Becker, S. J.; Daughtry, C. S. T.; Jain, D.; Karlekar, S. S.

2015-12-01

The US Army has an increasing focus on using automated remote sensing techniques with commercial multispectral imagery (MSI) to map urban and peri-urban agricultural and vegetative features; however, similar spectral profiles between trees (i.e., forest canopy) and other vegetation result in confusion between these cover classes. Established vegetation indices, like the Normalized Difference Vegetation Index (NDVI), are typically not effective in reliably differentiating between trees and other vegetation. Previous research in tree mapping has included integration of hyperspectral imagery (HSI) and LiDAR for tree detection and species identification, as well as the use of MSI to distinguish tree crowns from non-vegetated features. This project developed a straightforward method to model and also mask out trees from eight-band WorldView-2 (1.85 meter x 1.85 meter resolution at nadir) satellite imagery at the Beltsville Agricultural Research Center in Beltsville, MD spanning 2012 - 2015. The study site included tree cover, a range of agricultural and vegetative cover types, and urban features. The modeling method exploits the product of the red and red edge bands and defines accurate thresholds between trees and other land covers. Results show this method outperforms established vegetation indices including the NDVI, Soil Adjusted Vegetation Index, Normalized Difference Water Index, Simple Ratio, and Normalized Difference Red Edge Index in correctly masking trees while preserving the other information in the imagery. This method is useful when HSI and LiDAR collection are not possible or when using archived MSI.

Water Use by Urban Landscapes in Semi-Arid Environments

NASA Astrophysics Data System (ADS)

Litvak, E.; Pataki, D. E.

2017-12-01

Water use by urban trees and lawns constitutes a significant yet uncertain portion of urban water budgets. Reducing this uncertainty is essential for developing effective water conservation strategies that are critically needed in dry regions. Landscape water use is particularly difficult to estimate in semi-arid cities with diverse plant compositions and large proportions of non-native species sustained by irrigation. We developed an empirical model of urban evapotranspiration based on in situ measurements of 11 lawns and 108 trees that we previously collected in the greater Los Angeles area. The model in its current state considers urban landscapes as two-component systems comprised of lawns and trees, which have contrasting patterns of water use. Turfgrass lawns consume large amounts of irrigation water (up to 10 mm/d) that may be effectively reduced by the shade from trees. Trees consume much smaller amounts of water at common urban planting densities (0.1-2.6 mm/d), and provide shade over lawns. We estimated water use by irrigated landscapes in Los Angeles by combining this model with remotely sensed estimates of vegetation cover and ground-based vegetation surveys and weather data. According to our estimates, water use by Los Angeles landscapes was close to potential evapotranspiration ( 1,100 mm/yr), with turfgrass responsible for 64-84% of total water use. Landscape water use linearly increased with median household income across Los Angeles, where wealthier parts of the city were consistently more vegetated than less affluent parts. Our results indicate extremely high water use by urban landscapes in semi-arid environments, largely owing to high spatial coverage of excessively irrigated lawns. These results have important implications for constraining municipal water budgets and developing water-saving landscaping practices.

[Species composition, distribution and phenological characters of pollen-allergenic plants in Beijing urban area].

PubMed

Ouyang, Zhi-Yun; Xin, Jia-Nan; Zheng, Hua; Meng, Xue-Song; Wang, Xiao-Ke

2007-09-01

In order to know the species composition, distribution pattern, and phenological characteristics of pollen-allergenic plants in Beijing urban area, an investigation was made, combined with literature survey and experts interviews. The results showed that within the fifth ring of Beijing, there were 99 pollen-allergenic plant species belonging to 32 genera and 19 families, among which, 52 species were native plants, accounting for 52.5% of the total, 26 species were introduced from other regions of China, occupying 26.3% of the total, and 21 species were introduced from foreign countries, being 21.2% of the total. The 32 genera of pollen-allergenic plants in Beijing urban area were mainly North Temperate elements, occupying 40.6% , followed by Cosmopolitan and Pantropic elements. In all functional sections of Beijing urban area, the pollen-allergenic plants were most diversified in urban parks, and had the highest proportion in street tree species. The coverage of herbs with strong pollen allergy was in the order of waste lands > gym centers and institution yards > greenbelts > parks > residential areas > squares. The blooming period of pollen-allergenic arbors in Beijing urban area was concentrated in March and April, while that of pollen-allergenic herbs was from July to September.

Tree cover and species composition effects on academic performance of primary school students.

PubMed

Sivarajah, Sivajanani; Smith, Sandy M; Thomas, Sean C

2018-01-01

Human exposure to green space and vegetation is widely recognized to result in physical and mental health benefits; however, to date, the specific effects of tree cover, diversity, and species composition on student academic performance have not been investigated. We compiled standardized performance scores in Grades 3 and 6 for the collective student body in 387 schools across the Toronto District School Board (TDSB), and examined variation in relation to tree cover, tree diversity, and tree species composition based on comprehensive inventories of trees on school properties combined with aerial-photo-based assessments of tree cover. Analyses accounted for variation due to socioeconomic factors using the learning opportunity index (LOI), a regional composite index of external challenges to learning that incorporates income and other factors, such as students with English as a second language. As expected, LOI had the greatest influence on student academic performance; however, the proportion of tree cover, as distinct from other types of "green space" such as grass, was found to be a significant positive predictor of student performance, accounting for 13% of the variance explained in a statistical model predicting mean student performance assessments. The effects of tree cover and species composition were most pronounced in schools that showed the highest level of external challenges, suggesting the importance of urban forestry investments in these schools.

Tree cover and species composition effects on academic performance of primary school students

PubMed Central

Smith, Sandy M.; Thomas, Sean C.

2018-01-01

Human exposure to green space and vegetation is widely recognized to result in physical and mental health benefits; however, to date, the specific effects of tree cover, diversity, and species composition on student academic performance have not been investigated. We compiled standardized performance scores in Grades 3 and 6 for the collective student body in 387 schools across the Toronto District School Board (TDSB), and examined variation in relation to tree cover, tree diversity, and tree species composition based on comprehensive inventories of trees on school properties combined with aerial-photo-based assessments of tree cover. Analyses accounted for variation due to socioeconomic factors using the learning opportunity index (LOI), a regional composite index of external challenges to learning that incorporates income and other factors, such as students with English as a second language. As expected, LOI had the greatest influence on student academic performance; however, the proportion of tree cover, as distinct from other types of “green space” such as grass, was found to be a significant positive predictor of student performance, accounting for 13% of the variance explained in a statistical model predicting mean student performance assessments. The effects of tree cover and species composition were most pronounced in schools that showed the highest level of external challenges, suggesting the importance of urban forestry investments in these schools. PMID:29474503

Impacts of atmospheric nitrogen deposition on vegetation and soils in Joshua Tree National Park

Treesearch

E.B. Allen; L. Rao; R.J. Steers; A. Bytnerowicz; M.E. Fenn

2009-01-01

The western Mojave Desert is downwind of nitrogen emissions from coastal and inland urban sources, especially automobiles. The objectives of this research were to measure reactive nitrogen (N) in the atmosphere and soils along a N-deposition gradient at Joshua Tree National Park and to examine its effects on invasive and native plant species. Atmospheric nitric acid (...

Effect of Landscape Pattern on Insect Species Density within Urban Green Spaces in Beijing, China

PubMed Central

Su, Zhimin; Li, Xiaoma; Zhou, Weiqi; Ouyang, Zhiyun

2015-01-01

Urban green space is an important refuge of biodiversity in urban areas. Therefore, it is crucial to understand the relationship between the landscape pattern of green spaces and biodiversity to mitigate the negative effects of urbanization. In this study, we collected insects from 45 green patches in Beijing during July 2012 using suction sampling. The green patches were dominated by managed lawns, mixed with scattered trees and shrubs. We examined the effects of landscape pattern on insect species density using hierarchical partitioning analysis and partial least squares regression. The results of the hierarchical partitioning analysis indicated that five explanatory variables, i.e., patch area (with 19.9% independent effects), connectivity (13.9%), distance to nearest patch (13.8%), diversity for patch types (11.0%), and patch shape (8.3%), significantly contributed to insect species density. With the partial least squares regression model, we found species density was negatively related to patch area, shape, connectivity, diversity for patch types and proportion of impervious surface at the significance level of p < 0.05 and positively related to proportion of vegetated land. Regression tree analysis further showed that the highest species density was found in green patches with an area <500 m2. Our results indicated that improvement in habitat quality, such as patch area and connectivity that are typically thought to be important for conservation, did not actually increase species density. However, increasing compactness (low-edge) of patch shape and landscape composition did have the expected effect. Therefore, it is recommended that the composition of the surrounding landscape should be considered simultaneously with planned improvements in local habitat quality. PMID:25793897

Effect of landscape pattern on insect species density within urban green spaces in Beijing, China.

PubMed

Su, Zhimin; Li, Xiaoma; Zhou, Weiqi; Ouyang, Zhiyun

2015-01-01

Urban green space is an important refuge of biodiversity in urban areas. Therefore, it is crucial to understand the relationship between the landscape pattern of green spaces and biodiversity to mitigate the negative effects of urbanization. In this study, we collected insects from 45 green patches in Beijing during July 2012 using suction sampling. The green patches were dominated by managed lawns, mixed with scattered trees and shrubs. We examined the effects of landscape pattern on insect species density using hierarchical partitioning analysis and partial least squares regression. The results of the hierarchical partitioning analysis indicated that five explanatory variables, i.e., patch area (with 19.9% independent effects), connectivity (13.9%), distance to nearest patch (13.8%), diversity for patch types (11.0%), and patch shape (8.3%), significantly contributed to insect species density. With the partial least squares regression model, we found species density was negatively related to patch area, shape, connectivity, diversity for patch types and proportion of impervious surface at the significance level of p < 0.05 and positively related to proportion of vegetated land. Regression tree analysis further showed that the highest species density was found in green patches with an area <500 m2. Our results indicated that improvement in habitat quality, such as patch area and connectivity that are typically thought to be important for conservation, did not actually increase species density. However, increasing compactness (low-edge) of patch shape and landscape composition did have the expected effect. Therefore, it is recommended that the composition of the surrounding landscape should be considered simultaneously with planned improvements in local habitat quality.

Will Garry oak respond to release from overtopping conifers

Treesearch

Constance A. Harrington; Christel C. Kern

2002-01-01

Garry oak (Quercus garryana) woodlands provide unique habitat for many Pacific Northwest species but these habitats are rapidly disappearing as species composition shifts to conifer or land use changes to urban or agricultural. Many oak trees from former savannas or oak woodlands on Fort Lewis Military Reservation (near Tacoma, WA, USA) are currently...

What risk do invasive bark beetles and woodborers pose to forests of the western U.S.?: A case study of the Mediterranean pine engraver, Orthotomicus erosus

Treesearch

S.J. Seybold; M. Downing

2009-01-01

Recently reported, and likely to threaten the health of standing trees in the urban and peri-urban forests of the West, are at least five new subcortical insect/pathogen complexes [Agrilus coxalis Waterhouse (Buprestidae) and four species of Scolytidae: Orthotomicus (Ips) erosus (Wollaston), Hylurgus lignipderda...

Grand Forks - East Grand Forks Urban Water Resources Study. Background Information Appendix.

DTIC Science & Technology

1981-07-01

Social Organization 121 Introduction 121 Demography 122 Racial Distribution 139 Ethnic Groups 141 Neighborhood Groups 141 Religion 143 Crime 144...of agricultural clearing operations and urban growth. Native tree species are important because of their longevity and now relatively infrequent... Demography Geographic Distribution Governmental Organiization Economy Occupational Structure Education Social Support Services 109 CULTURAL ELEM1ENTS

Development of oligonucleotide microarrays for simultaneous multi-species identification of Phellinus tree-pathogenic fungi.

PubMed

Tzean, Yuh; Shu, Po-Yao; Liou, Ruey-Fen; Tzean, Shean-Shong

2016-03-01

Polyporoid Phellinus fungi are ubiquitously present in the environment and play an important role in shaping forest ecology. Several species of Phellinus are notorious pathogens that can affect a broad variety of tree species in forest, plantation, orchard and urban habitats; however, current detection methods are overly complex and lack the sensitivity required to identify these pathogens at the species level in a timely fashion for effective infestation control. Here, we describe eight oligonucleotide microarray platforms for the simultaneous and specific detection of 17 important Phellinus species, using probes generated from the internal transcribed spacer regions unique to each species. The sensitivity, robustness and efficiency of this Phellinus microarray system was subsequently confirmed against template DNA from two key Phellinus species, as well as field samples collected from tree roots, trunks and surrounding soil. This system can provide early, specific and convenient detection of Phellinus species for forestry, arboriculture and quarantine inspection, and could potentially help to mitigate the environmental and economic impact of Phellinus-related diseases. © 2015 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

Potential of two submontane broadleaved species (Acer opalus, Quercus pubescens) to reveal spatiotemporal patterns of rockfall activity

NASA Astrophysics Data System (ADS)

Favillier, Adrien; Lopez-Saez, Jérôme; Corona, Christophe; Trappmann, Daniel; Toe, David; Stoffel, Markus; Rovéra, Georges; Berger, Frédéric

2015-10-01

Long-term records of rockfalls have proven to be scarce and typically incomplete, especially in increasingly urbanized areas where inventories are largely absent and the risk associated with rockfall events rises proportionally with urbanization. On forested slopes, tree-ring analyses may help to fill this gap, as they have been demonstrated to provide annually-resolved data on past rockfall activity over long periods. Yet, the reconstruction of rockfall chronologies has been hampered in the past by the paucity of studies that include broadleaved tree species, which are, in fact, quite common in various rockfall-prone environments. In this study, we test the sensitivity of two common, yet unstudied, broadleaved species - Quercus pubescens Willd. (Qp) and Acer opalus Mill. (Ao) - to record rockfall impacts. The approach is based on a systematic mapping of trees and the counting of visible scars on the stem surface of both species. Data are presented from a site in the Vercors massif (French Alps) where rocks are frequently detached from Valanginian limestone and marl cliffs. We compare recurrence interval maps obtained from both species and from two different sets of tree structures (i.e., single trees vs. coppice stands) based on Cohen's k coefficient and the mean absolute error. A total of 1230 scars were observed on the stem surface of 847 A. opalus and Q. pubescens trees. Both methods yield comparable results on the spatial distribution of relative rockfall activity with similar downslope decreasing recurrence intervals. Yet recurrence intervals vary significantly according to tree species and tree structure. The recurrence interval observed on the stem surface of Q. pubescens exceeds that of A. opalus by > 20 years in the lower part of the studied plot. Similarly, the recurrence interval map derived from A. opalus coppice stands, dominant at the stand scale, does not exhibit a clear spatial pattern. Differences between species may be explained by the bark thickness of Q. pubescens, which has been demonstrated to grow at twice the rate of A. opalus, thus constituting a mechanical barrier that is able to buffer low energy rockfalls and thus can avoid damage to the underlying tissues. The reasons for differences between tree structures are related to the clustered coppice-specific spatial stem distribution in clumps that could result on one hand in bigger gaps between clumps, which in turn decreases the probability of tree impacts for traveling blocks. On the other hand, data also indicate that several scars on the bark of coppice stands may stem from the same impact and thus may lead to an overestimation of rockfall activity.

Monitoring the invasion of an exotic tree (Ligustrum lucidum) from 1983 to 2006 with Landsat TM/ETM+ satellite data and support vector machines in Cordoba, Argentina

Treesearch

Gregorio I. Gavier-Pizarro; Tobias Kuemmerle; Laura E. Hoyos; Susan I. Stewart; Cynthia D. Huebner; Nicholas S. Keuler; Volker C. Radeloff

2012-01-01

In central Argentina, the Chinese tree glossy privet (Ligustrum lucidum) is an aggressive invasive species replacing native forests, forming dense stands, and is thus a major conservation concern. Mapping the spread of biological invasions is a necessary first step toward understanding the factors determining invasion patterns. Urban areas may...

Evaluating Tree Protection Devices: Effects on Growth and Survival–First-Year Results

Treesearch

L. R. Costello; R. H. Schmidt; Gregory A. Giusti

1991-01-01

The protection of seedlings from animal browsing is critical for the survival and growth of many tree species. This is particularly true in wildland areas and arid areas (McAuliffe, 1986), and oftentimes in urban areas. A variety of techniques and devices have been used to protect seedlings, from using straw stubble to milk cartons to plastic or metal screens. Recently...

Evapotranspiration of urban landscapes in Los Angeles, California at the municipal scale

NASA Astrophysics Data System (ADS)

Litvak, E.; Manago, K. F.; Hogue, T. S.; Pataki, D. E.

2017-05-01

Evapotranspiration (ET), an essential process in biosphere-atmosphere interactions, is highly uncertain in cities that maintain cultivated and irrigated landscapes. We estimated ET of irrigated landscapes in Los Angeles by combining empirical models of turfgrass ET and tree transpiration derived from in situ measurements with previously developed remotely sensed estimates of vegetation cover and ground-based vegetation surveys. We modeled irrigated landscapes as a two-component system comprised of trees and turfgrass to assess annual and spatial patterns of ET. Annual ET from vegetated landscapes (ETveg) was 1110 ± 53 mm/yr and ET from the whole city (vegetated and nonvegetated areas, ETland) was three times smaller, reflecting the fractional vegetation cover. With the exception of May and June, monthly ETland was significantly higher than predicted by the North American Land Data Assimilation System. ETveg was close to potential ET, indicating abundant irrigation inputs. Monthly averaged ETveg varied from 1.5 ± 0.1 mm/d (December) to 4.3 ± 0.2 mm/d (June). Turfgrass was responsible for ˜70% of ETveg. For trees, angiosperm species (71% of all trees) contributed over 90% to total tree transpiration, while coniferous and palm species made very small contributions. ETland was linearly correlated with median household income across the city, confirming the importance of social factors in determining spatial distribution of urban vegetation. These estimates have important implications for constraining the municipal water budget of Los Angeles and improving regional-scale hydrologic models, as well as for developing water-saving practices. The methodology used in this study is also transferable to other semiarid regions for quantification of urban landscape ET.

Pb and Cd Contents in Soil, Water, and Trees at an Afforestation Site, South China.

PubMed

Pei, Nancai; Chen, Bufeng; Liu, Shuguang

2015-11-01

Pb and Cd contents in 13 plantation tree species (leaf and branch components), soil, water (groundwater and river water) at a young (3-5 year-old) seashore afforestation stand were investigated in Nansha district, Guangzhou city in southern China. The results showed that (1) soil, rather than water or trees, had the highest content of both Pb (averagely 48.79 mg/kg) and Cd (0.50 mg/kg), demonstrating that soil might function as a major reservoir for extraneously derived heavy metals; (2) Pb content was higher in branches than in leaves, but Cd content appeared similar in both components, implying possibly different accumulation mechanisms in trees; (3) Pb and Cd appeared to accumulate differently among some tree taxa, whereas almost no significant difference was detected between introduced and indigenous species. The study indicated that trees were potentially useful to remediate sites contaminated with Pb and Cd in the urbanized areas.

Isolation, Identification and Molecular Typing of Cryptococcus neoformans from Pigeon Droppings and Other Environmental Sources in Tripoli, Libya.

PubMed

Ellabib, Mohamed S; Aboshkiwa, Mohamed A; Husien, Walid M; D'Amicis, Roberta; Cogliati, Massimo

2016-08-01

Cryptococcus neoformans and C. gattii are the major cause of fungal meningitis, a potentially lethal mycosis. Since pigeon excreta and other environmental sources can be considered a significant environmental reservoir of this species in urban areas, 100 samples of pigeon excreta and 420 samples from Eucalyptus camaldulensis and Olea europaea (olive tree) around the city of Tripoli, Libya, were collected. C. neoformans was isolated and identified using standard biochemical assays from 46 samples: 34 from pigeon droppings, 3 from Eucalyptus trees and 9 from olive trees. Molecular typing revealed that all isolates from pigeon droppings belonged to molecular type VNI (C. neoformans var. grubii) and mating type αA, whereas those from trees included also the molecular type VNII and VNIII (AD hybrids). The present study reports, for the first time, information about the distribution of species, mating types and molecular types of C. neoformans/C. gattii species complex in Libya.

Impact of urbanization on abundance and phenology of caterpillars and consequences for breeding in an insectivorous bird.

PubMed

Seress, Gábor; Hammer, Tamás; Bókony, Veronika; Vincze, Ernő; Preiszner, Bálint; Pipoly, Ivett; Sinkovics, Csenge; Evans, Karl L; Liker, András

2018-04-20

Urbanization can have marked effects on plant and animal populations' phenology, population size, predator-prey interactions and reproductive success. These aspects are rarely studied simultaneously in a single system, and some are rarely investigated, e.g. how insect phenology responds to urban development. Here, we study a tri-trophic system of trees - phytophagous insects (caterpillars) - insectivorous birds (great tits) to assess how urbanization influences i) the phenology of each component of this system, ii) insect abundance and iii) avian reproductive success. We use data from two urban and two forest sites in Hungary, central Europe, collected over four consecutive years. Despite a trend of earlier leaf emergence in urban sites there is no evidence for an earlier peak in caterpillar abundance. Thus, contrary to the frequently stated prediction in the literature, the earlier breeding of urban bird populations is not associated with an earlier peak in caterpillar availability. Despite this the seasonal dynamics of caterpillar biomass exhibited striking differences between habitat types with a single clear peak in forests, and several much smaller peaks in urban sites. Caterpillar biomass was higher in forests than urban areas across the entire sampling period, and between 8.5 and 24 times higher during the first brood's chick-rearing period. This higher biomass was not associated with taller trees in forest sites, or with tree species identity, and occurred despite most of our focal trees being native to the study area. Urban great tits laid smaller clutches, experienced more frequent nestling mortality from starvation, reared fewer offspring to fledging age, and their fledglings had lower body mass. Our study strongly indicates that food limitation is responsible for lower avian reproductive success in cities, which is driven by reduced availability of the preferred nestling diet, i.e. caterpillars, rather than phenological shifts in the timing of peak food availability. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Pourable Artificial Diet for Rearing Anoplophora glabripennis (Coleoptera: Cerambycidae) and Methods to Optimize Larval Survival and Synchronize Development

Treesearch

M.A. Keena

2005-01-01

Aiaoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae), is a recently introduced non-native invasive species in the United States that has the potential to destroy several tree species in urban and forest habitats. The ability to rear A. glabripennis in quarantine is critical to rapid progress on techniques for the...

Effects of Temperature on Anoplophora glabripennis (Coleoptera: Cerambycidae) Adult Survival, Reproduction, and Egg Hatch

Treesearch

Melody A. Keena

2006-01-01

Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae) is a recently introduced non-native invasive species in North America that has the potential to destroy several tree species in urban and forest habitats. Adult survival, reproduction, and egg hatch of A. glabripennis from two populations (Ravenswood, Chicago, IL, and Bayside, Queens, NY) were evaluated...

Formulaic expert method to integrate evaluation and valuation of heritage trees in compact city.

PubMed

Jim, C Y

2006-05-01

Urban trees serve important environmental, social and economic functions, but similar to other natural endowments they are not customarily depicted in monetary terms. The needs to augment protection, funding and community support for urban greening call for proper valuation. Heritage trees (HTs), the cream of urban-tree stock, deserve special attention. Existing assessment methods do not give justice to outstanding trees in compact cities deficient in high-caliber greenery, and to their social-cultural-historical importance. They artificially separate evaluation from valuation, which should be a natural progression from the former. Review of tree valuation methods suggested the formula approach to be more suitable than contingent valuation and hedonic pricing, and provided hints on their strengths and weaknesses. This study develops an alternative formulaic expert method (FEM) that integrates evaluation and valuation, maximizes objectivity, broadly encompasses the key tree, tree-environment and tree-human traits, and accords realistic monetary value to HTs. Six primary criteria (dimension, species, tree, condition, location, and outstanding consideration) branched into 45 secondary criteria, each allocated numerical marks. Each primary criterion was standardized to carry equal weight, and a tree's maximum aggregate score is capped at 100. A Monetary Assignment Factor (MAF) to consign dollar value to each score unit was derived from three-year average per m(2) sale price of medium-sized residential flats. The applicability of FEM was tested on selected HTs in compact Hong Kong. The aggregate score of a tree multiplied by MAF yielded monetary value, which was on average 66 times higher than the result from the commonly-adopted Council of Tree and Landscape Appraisers method. The computed tree values could be publicized together with multiple tree benefits to raise understanding and awareness and rally support to protect HTs. The property-linked FEM could be flexibly applied to other cities, especially to assess HTs in compact developing cities.

High resolution remote sensing for reducing uncertainties in urban forest carbon offset life cycle assessments.

PubMed

Tigges, Jan; Lakes, Tobia

2017-10-04

Urban forests reduce greenhouse gas emissions by storing and sequestering considerable amounts of carbon. However, few studies have considered the local scale of urban forests to effectively evaluate their potential long-term carbon offset. The lack of precise, consistent and up-to-date forest details is challenging for long-term prognoses. Therefore, this review aims to identify uncertainties in urban forest carbon offset assessment and discuss the extent to which such uncertainties can be reduced by recent progress in high resolution remote sensing. We do this by performing an extensive literature review and a case study combining remote sensing and life cycle assessment of urban forest carbon offset in Berlin, Germany. Recent progress in high resolution remote sensing and methods is adequate for delivering more precise details on the urban tree canopy, individual tree metrics, species, and age structures compared to conventional land use/cover class approaches. These area-wide consistent details can update life cycle inventories for more precise future prognoses. Additional improvements in classification accuracy can be achieved by a higher number of features derived from remote sensing data of increasing resolution, but first studies on this subject indicated that a smart selection of features already provides sufficient data that avoids redundancies and enables more efficient data processing. Our case study from Berlin could use remotely sensed individual tree species as consistent inventory of a life cycle assessment. However, a lack of growth, mortality and planting data forced us to make assumptions, therefore creating uncertainty in the long-term prognoses. Regarding temporal changes and reliable long-term estimates, more attention is required to detect changes of gradual growth, pruning and abrupt changes in tree planting and mortality. As such, precise long-term urban ecological monitoring using high resolution remote sensing should be intensified, especially due to increasing climate change effects. This is important for calibrating and validating recent prognoses of urban forest carbon offset, which have so far scarcely addressed longer timeframes. Additionally, higher resolution remote sensing of urban forest carbon estimates can improve upscaling approaches, which should be extended to reach a more precise global estimate for the first time. Urban forest carbon offset can be made more relevant by making more standardized assessments available for science and professional practitioners, and the increasing availability of high resolution remote sensing data and the progress in data processing allows for precisely that.

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

NASA Astrophysics Data System (ADS)

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.

Environmental studies in two communes of Santiago de Chile by the analysis of magnetic properties of particulate matter deposited on leaves of roadside trees

NASA Astrophysics Data System (ADS)

Muñoz, David; Aguilar, Bertha; Fuentealba, Raúl; Préndez, Margarita

2017-03-01

Emissions from motor vehicles are considered to be one of the main sources of airborne particulate matter in Santiago. International researchers have shown that particulate matter contains metal oxides and magnetic particles, both of which are emitted mainly from vehicles exhaust pipes. On the other hand, trees are effective in reducing such contamination, so that they act as passive collectors of particulate matter. This work presents the results obtained from the first magnetic study of the particulate matter collected in two areas of the city of Santiago de Chile. Magnetic susceptibility and Saturation Isothermic Remanent Magnetization (SIRM) were determined in leaves from abundant urban trees and from urban dust samples. Results indicate that most of the samples contain ferromagnetic minerals with magnetite (Fe3O4) as the main carrier. Values of magnetic susceptibility (SI ×10-6 m3/kg) in the range 0.04-0.24 for leaves and in the range 10-45 for urban dust were determinated. In one of the city areas studied, significant correlation between the particulate matter deposited on leaves of Platanus orientalis and measured traffic flows was obtained. In addition, it was possible to estimate that the species Platanus orientalis and Acer negundo have a better ability to capture particulate matter than the species Robinia pseudoacacia.

110 Years of change in urban tree stocks and associated carbon storage.

PubMed

Díaz-Porras, Daniel F; Gaston, Kevin J; Evans, Karl L

2014-04-01

Understanding the long-term dynamics of urban vegetation is essential in determining trends in the provision of key resources for biodiversity and ecosystem services and improving their management. Such studies are, however, extremely scarce due to the lack of suitable historical data. We use repeat historical photographs from the 1900s, 1950s, and 2010 to assess general trends in the quantity and size distributions of the tree stock in urban Sheffield and resultant aboveground carbon storage. Total tree numbers declined by a third from the 1900s to the 1950s, but increased by approximately 50% from the 1900s-2010, and by 100% from the 1950s-2010. Aboveground carbon storage in urban tree stocks had doubled by 2010 from the levels present in the 1900s and 1950s. The initial decrease occurred at a time when national and regional tree stocks were static and are likely to be driven by rebuilding following bombing of the urban area during the Second World War and by urban expansion. In 2010, trees greater than 10 m in height comprised just 8% of those present. The increases in total tree numbers are thus largely driven by smaller trees and are likely to be associated with urban tree planting programmes. Changes in tree stocks were not constant across the urban area but varied with the current intensity of urbanization. Increases from 1900 to 2010 in total tree stocks, and smaller sized trees, tended to be greatest in the most intensely urbanized areas. In contrast, the increases in the largest trees were more marked in areas with the most green space. These findings emphasize the importance of preserving larger fragments of urban green space to protect the oldest and largest trees that contribute disproportionately to carbon storage and other ecosystem services. Maintaining positive trends in urban tree stocks and associated ecosystem service provision will require continued investment in urban tree planting programmes in combination with additional measures, such as revisions to tree preservation orders, to increase the retention of such trees as they mature.

An inventory of trees in Dublin city centre.

PubMed

Ningal, Tine; Mills, Gerald; Smithwick, Pamela

2010-01-01

While urban areas are often considered to be comprised chiefly of artificial surfaces, they can contain a substantial portion of green space and a great diversity of natural habitats. These spaces include public parks, private gardens and street trees, all of which can provide valuable environmental services, such as improved air quality. Trees play a particular role in cities as they are often placed along roadsides and in the median strip of busy streets. As such they regulate access to sunshine, restrict airflow, provide shelter, scavenge air pollutants and manage noise at the street level. A tree planting policy can be an important part of a broader environmental strategy aimed at improving the quality of life in urban areas but this requires up-to-date knowledge of the current tree stock, which does not exist for Dublin. This article presents an inventory of trees in Dublin's city centre, defined as the area between the Grand and Royal canals. The results show that there are over 10,000 trees in the study area representing a density of 684 trees km-2 or one tree to approximately every 50 residents of the city centre. The tree canopy extent when in full foliage was nearly 1 km2 in extent or 6% of the study area. A more detailed analysis of those trees planted along streets shows little species variation but clear distinction in the sizes of trees, which is indicative of the age of planting. These data are used to estimate the carbon stored in Dublin's trees.

Compensatory value of an urban forest: an application of the tree-value formula

Treesearch

David J. Nowak

1993-01-01

Understanding the value of an urban forest can give decisionmakers a better foundation for urban tree management. According to the tree-valuation formula of the Council of Tree and Landscape Appraisers, the estimated compensatory value of the urban forest in Oakland, California, (21% tree cover) is $385.7 million, with residential trees accounting for 58.6% of the...

Seed dispersal turns an experimental plantation on degraded land into a novel forest in urban northern Puerto Rico

Treesearch

Oscar Abelleira; Elvia J. Meléndez Ackerman; Diana García Montiel; John A. Parrotta

2015-01-01

Planting tree species with desirable traits may catalyze forest regeneration in increasingly common degraded lands by restoring soil properties and attracting seed dispersers. We sampled forest regeneration in an experimental plantation of Albizia lebbek, an introduced N-fixing species, on a degraded pasture in northern Puerto Rico, 27 years after its establishment. We...

Climate change accelerates growth of urban trees in metropolises worldwide.

PubMed

Pretzsch, Hans; Biber, Peter; Uhl, Enno; Dahlhausen, Jens; Schütze, Gerhard; Perkins, Diana; Rötzer, Thomas; Caldentey, Juan; Koike, Takayoshi; Con, Tran van; Chavanne, Aurélia; Toit, Ben du; Foster, Keith; Lefer, Barry

2017-11-13

Despite the importance of urban trees, their growth reaction to climate change and to the urban heat island effect has not yet been investigated with an international scope. While we are well informed about forest growth under recent conditions, it is unclear if this knowledge can be simply transferred to urban environments. Based on tree ring analyses in ten metropolises worldwide, we show that, in general, urban trees have undergone accelerated growth since the 1960s. In addition, urban trees tend to grow more quickly than their counterparts in the rural surroundings. However, our analysis shows that climate change seems to enhance the growth of rural trees more than that of urban trees. The benefits of growing in an urban environment seem to outweigh known negative effects, however, accelerated growth may also mean more rapid ageing and shortened lifetime. Thus, city planners should adapt to the changed dynamics in order to secure the ecosystem services provided by urban trees.

A Technical Guide to Urban Community Forestry: Urban and Community Forestry: Improving Our Quality of Life

Treesearch

USDA Forest Service

1993-01-01

Trees growing within cities and towns form a forest-an urban forest. But urban trees require special attention, because they are expected to exist within the urban environment. With its infrastructure of streets, sidewalks, curbs, buried utilities, overhead power lines and buildings, the urban environment places tremendous stresses on trees. With proper care, trees...

Influence of Urbanization on Demography of Little Brown Bats (Myotis lucifugus) in the Prairies of North America

PubMed Central

Coleman, Joanna L.; Barclay, Robert M. R.

2011-01-01

Background We address three key gaps in research on urban wildlife ecology: insufficient attention to (1) grassland biomes, (2) individual- and population-level effects, and (3) vertebrates other than birds. We hypothesized that urbanization in the North American Prairies, by increasing habitat complexity (via the proliferation of vertical structures such as trees and buildings), thereby enhancing the availability of day-roosts, tree cover, and insects, would benefit synanthropic bats, resulting in increased fitness among urban individuals. Methodology/Principal Findings Over three years, we captured more than 1,600 little brown bats (Myotis lucifugus) in urban and non-urban riparian sites in and around Calgary, Alberta, Canada. This species dominated bat assemblages throughout our study area, but nowhere more so than in the city. Our data did not support most of our specific predictions. Increased numbers of urban bats did not reflect urbanization-related benefits such as enhanced body condition, reproductive rates, or successful production of juveniles. Instead, bats did best in the transition zone situated between strictly urban and rural areas. Conclusions/Significance We reject our hypothesis and explore various explanations. One possibility is that urban and rural M. lucifugus exhibit increased use of anthropogenic roosts, as opposed to natural ones, leading to larger maternity colonies and higher population densities and, in turn, increased competition for insect prey. Other possibilities include increased stress, disease transmission and/or impacts of noise on urban bats. Whatever the proximate cause, the combination of greater bat population density with decreased body condition and production of juveniles indicates that Calgary does not represent a population source for Prairie bats. We studied a highly synanthropic species in a system where it could reasonably be expected to respond positively to urbanization, but failed to observe any apparent benefits at the individual level, leading us to propose that urban development may be universally detrimental to bats. PMID:21857890

A field study on solar-induced chlorophyll fluorescence and pigment parameters along a vertical canopy gradient of four tree species in an urban environment.

PubMed

Van Wittenberghe, Shari; Alonso, Luis; Verrelst, Jochem; Hermans, Inge; Valcke, Roland; Veroustraete, Frank; Moreno, José; Samson, Roeland

2014-01-01

To better understand the potential uses of vegetation indices based on the sun-induced upward and downward chlorophyll fluorescence at leaf and at canopy scales, a field study was carried out in the city of Valencia (Spain). Fluorescence yield (FY) indices were derived for trees at different traffic intensity locations and at three canopy heights. This allowed investigating within-tree and between-tree variations of FY indices for four tree species. Several FY indices showed a significant (p < 0.05) and important effect of tree location for the species Morus alba (white mulberry) and Phoenix canariensis (Canary Island date palm). The upward FY parameters of M. alba, and the upward to downward ratios at 687 and 741 nm for both species, were significantly related to tree location. It was found that not the total chlorophyll (Chl) content, but rather the Chl a/b ratio showed the strongest correlations with several of the indices applied. Chl a/b was lowest at the bottom level of the highest traffic intensity location for both species due to an increased Chl b, indicating a larger light harvesting complex related to Photosystem II (LHCII) as a response to limiting light. The leaf deposits from traffic observed at this sampling location possibly led to a shading effect, resulting further in an adaptive response of the photosynthetic system and subsequent difference of FY indices. This study therefore indicated the importance of the size of LHCII on the fluorescence emission, observed under different traffic generated pollution conditions. © 2013.

Indoor simulations reveal differences among plant species in capturing particulate matter

PubMed Central

Chen, Jungang; Yu, Xinxiao; Bi, Huaxing; Fu, Yanlin

2017-01-01

A number of studies have focused on the capacity of urban trees and shrubs to serve as efficient biological filters to mitigate air pollution. In this study, five different tree species were assessed for this function. Kerria japonica, Sophora japonica, Philadelphus pekinensis, Gleditsia sinensis, and Prunus persica 'Atropurpurea' were tested in a deposition chamber using (NH4)2SO4 particles. We quantified and compared the capability of all tested trees to remove particles by assessing deposition velocity, a measure of the ability to remove particles. When placed in the deposition chamber, S. japonica had the greatest deposition velocity, followed by Philadelphus pekinensis, G. sinensis, Prunus persica 'Atropurpurea,' and K. japonica, in descending order. In addition, the comparison of deposition velocities among these species suggested that certain leaf geometries and surface characteristics of broadleaf trees, such as trichomes and grooves, increased particle capture. However, these results change under a different simulation condition using ambient air, suggesting that some trees actually increase pollutant number concentrations more than reduce particle concentration. This outcome can be explained by the aerodynamic effect of trees exceeding the filtering capacity of vegetation under some conditions. This highlights the difficulty of generalizing species selection criteria for practice use. Accordingly, our results indicate that using vegetation to reduce particle pollution and improve the air quality is not a universally advisable and viable solution. PMID:28520744

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

PubMed

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.

Multi-scale comparison of the fine particle removal capacity of urban forests and wetlands.

PubMed

Zhang, Zhenming; Liu, Jiakai; Wu, Yanan; Yan, Guoxin; Zhu, Lijuan; Yu, Xinxiao

2017-04-10

As fine particle (FP) pollution is harmful to humans, previous studies have focused on the mechanisms of FP removal by forests. The current study aims to compare the FP removal capacities of urban forests and wetlands on the leaf, canopy, and landscape scales. Water washing and scanning electron microscopy are used to calculate particle accumulation on leaves, and models are used to estimate vegetation collection, sedimentation, and dry deposition. Results showed that, on the leaf scale, forest species are able to accumulate more FP on their leaf surface than aquatic species in wetlands. On the canopy scale, horizontal vegetation collection is the major process involved in FP removal, and the contribution of vertical sedimentation/emission can be ignored. Coniferous tree species also showed stronger FP collection ability than broadleaf species. In the landscape scale, deposition on the forest occurs to a greater extent than that on wetlands, and dry deposition is the major process of FP removal on rain-free days. In conclusion, when planning an urban green system, planting an urban forest should be the first option for FP mitigation.

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

Treesearch

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

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...

Urban warming reduces aboveground carbon storage.

PubMed

Meineke, Emily; Youngsteadt, Elsa; Dunn, Robert R; Frank, Steven D

2016-10-12

A substantial amount of global carbon is stored in mature trees. However, no experiments to date test how warming affects mature tree carbon storage. Using a unique, citywide, factorial experiment, we investigated how warming and insect herbivory affected physiological function and carbon 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. © 2016 The Author(s).

City life makes females fussy: sex differences in habitat use of temperate bats in urban areas

PubMed Central

Lintott, Paul R.; Bunnefeld, Nils; Fuentes-Montemayor, Elisa; Minderman, Jeroen; Mayhew, Rebekah J.; Olley, Lena; Park, Kirsty J.

2014-01-01

Urbanization is a major driver of the global loss of biodiversity; to mitigate its adverse effects, it is essential to understand what drives species' patterns of habitat use within the urban matrix. While many animal species are known to exhibit sex differences in habitat use, adaptability to the urban landscape is commonly examined at the species level, without consideration of intraspecific differences. The high energetic demands of pregnancy and lactation in female mammals can lead to sexual differences in habitat use, but little is known of how this might affect their response to urbanization. We predicted that female Pipistrellus pygmaeus would show greater selectivity of forging locations within urban woodland in comparison to males at both a local and landscape scale. In line with these predictions, we found there was a lower probability of finding females within woodlands which were poorly connected, highly cluttered, with a higher edge : interior ratio and fewer mature trees. By contrast, habitat quality and the composition of the surrounding landscape were less of a limiting factor in determining male distributions. These results indicate strong sexual differences in the habitat use of fragmented urban woodland, and this has important implications for our understanding of the adaptability of bats and mammals more generally to urbanization. PMID:26064557

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

Treesearch

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...

Interaction between forest biodiversity and people's use of forest resources in Roviana, Solomon Islands: implications for biocultural conservation under socioeconomic changes.

PubMed

Furusawa, Takuro; Sirikolo, Myknee Qusa; Sasaoka, Masatoshi; Ohtsuka, Ryutaro

2014-01-27

In Solomon Islands, forests have provided people with ecological services while being affected by human use and protection. This study used a quantitative ethnobotanical analysis to explore the society-forest interaction and its transformation in Roviana, Solomon Islands. We compared local plant and land uses between a rural village and urbanized village. Special attention was paid to how local people depend on biodiversity and how traditional human modifications of forest contribute to biodiversity conservation. After defining locally recognized land-use classes, vegetation surveys were conducted in seven forest classes. For detailed observations of daily plant uses, 15 and 17 households were randomly selected in the rural and urban villages, respectively. We quantitatively documented the plant species that were used as food, medicine, building materials, and tools. The vegetation survey revealed that each local forest class represented a different vegetative community with relatively low similarity between communities. Although commercial logging operations and agriculture were both prohibited in the customary nature reserve, local people were allowed to cut down trees for their personal use and to take several types of non-timber forest products. Useful trees were found at high frequencies in the barrier island's primary forest (68.4%) and the main island's reserve (68.3%). Various useful tree species were found only in the reserve forest and seldom available in the urban village. In the rural village, customary governance and control over the use of forest resources by the local people still functioned. Human modifications of the forest created unique vegetation communities, thus increasing biodiversity overall. Each type of forest had different species that varied in their levels of importance to the local subsistence lifestyle, and the villagers' behaviors, such as respect for forest reserves and the semidomestication of some species, contributed to conserving diversity. Urbanization threatened this human-forest interaction. Although the status of biodiversity in human-modified landscapes is not fully understood, this study suggested that traditional human modifications can positively affect biodiversity and that conservation programs should incorporate traditional uses of landscapes to be successful.

Differences in photosynthesis and isoprene emission in post oak (Quercus stellata) and sweetgum (Liquidambar styraciflua) trees along an urban-to-rural gradient in Texas

NASA Astrophysics Data System (ADS)

Crossett, C.; Lahr, E.; Haas, G.; Schade, G. W.

2014-12-01

Many plants produce isoprene, a volatile organic compound that can mitigate damage to photosynthetic systems during short- or long-term increases in leaf temperature. After its production within leaves, isoprene is emitted to the atmosphere and influences regional atmospheric chemistry. Here, we use an urban-to-rural gradient to explore future effects of climate change on tree eco-physiology and feedbacks to atmospheric chemistry. Urban areas mimic many of the conditions expected to occur in the future; in particular, cities have warmer temperatures due to the urban heat island (UHI) effect, and less water availability relative to rural areas. Along a 90 km urban-to-rural gradient, we measured photosynthesis and isoprene emission from trees at three sites in eastern Texas: Houston (urban), The Woodlands (suburban) and Sam Houston National Forest (rural). Isoprene emission from post oak (Quercus stellata) was higher in Houston than the other sites, and when leaf temperatures were increased above ambient conditions, trees produced more isoprene. Leaves produced more isoprene at high leaf temperatures in early summer than in late summer, suggesting gradual acclimation of photosynthetic processes over the course of the summer. We also found that sweetgum (Liquidambar styraciflua) emitted more isoprene than post oak, but when leaf temperatures were increased, isoprene emission was exhausted more quickly in sweetgum relative to post oak. At the same time, post oak maintained higher levels of photosynthesis seasonally and during short-term temperature increases. Both post oak and sweetgum are significant isoprene emitters and represent approximately two and four percent crown cover in the United States, respectively. Our results suggest that in a warming climate, we can expect trees to produce more isoprene seasonally and in response to short-term temperature extremes, and that species-specific differences in photosynthesis and isoprene emission may play an important role in forest dynamics, particularly in long-term forest growth and carbon storage. Further exploration of the interactive effect of increased CO2, temperature, and drought on tree physiology will improve our understanding of forest dynamics and forest-climate feedbacks.

Biotic homogenization of three insect groups due to urbanization.

PubMed

Knop, Eva

2016-01-01

Cities are growing rapidly, thereby expected to cause a large-scale global biotic homogenization. Evidence for the homogenization hypothesis is mostly derived from plants and birds, whereas arthropods have so far been neglected. Here, I tested the homogenization hypothesis with three insect indicator groups, namely true bugs, leafhoppers, and beetles. In particular, I was interested whether insect species community composition differs between urban and rural areas, whether they are more similar between cities than between rural areas, and whether the found pattern is explained by true species turnover, species diversity gradients and geographic distance, by non-native or specialist species, respectively. I analyzed insect species communities sampled on birch trees in a total of six Swiss cities and six rural areas nearby. In all indicator groups, urban and rural community composition was significantly dissimilar due to native species turnover. Further, for bug and leafhopper communities, I found evidence for large-scale homogenization due to urbanization, which was driven by reduced species turnover of specialist species in cities. Species turnover of beetle communities was similar between cities and rural areas. Interestingly, when specialist species of beetles were excluded from the analyses, cities were more dissimilar than rural areas, suggesting biotic differentiation of beetle communities in cities. Non-native species did not affect species turnover of the insect groups. However, given non-native arthropod species are increasing rapidly, their homogenizing effect might be detected more often in future. Overall, the results show that urbanization has a negative large-scale impact on the diversity specialist species of the investigated insect groups. Specific measures in cities targeted at increasing the persistence of specialist species typical for the respective biogeographic region could help to stop the loss of biodiversity. © 2015 John Wiley & Sons Ltd.

Urban Watershed Forestry Manual Part 3: Urban Tree Planting Guide

Treesearch

Karen Cappiella; Tom Schueler; Tiffany Wright; Jennifer Tomlinson

2006-01-01

This is the third in a three-manual series on using trees to protect and restore urban watersheds. A brief description of each part follows. Part 3. Urban Tree Planting Guide provides detailed guidance on urban tree planting that is applicable at both the development site and the watershed scales. Topics covered include site assessment, planting design, site...

Growing and marketing woody species to support pollinators: An emerging opportunity for forest, conservation, and native plant nurseries in the Northeastern United States

Treesearch

Kas Dumroese; Tara Luna

2016-01-01

The decline of insects that pollinate flowers is garnering more attention by land managers, policymakers, and the general public. Nursery managers who grow native trees, shrubs, and woody vines have a promising opportunity to showcase these species, marketing their contributions to pollinator health and other ecosystem services in urban and wild landscapes....

Measuring urban tree loss dynamics across residential landscapes

EPA Science Inventory

The spatial arrangement of urban vegetation depends on urban morphology and socio-economic settings. Urban vegetation changes over time because of human management. Urban trees are removed due to hazard prevention or aesthetic preferences. Previous research attributed tree loss t...

Urban tree database and allometric equations

Treesearch

E. Gregory McPherson; Natalie S. van Doorn; Paula J.  Peper

2016-01-01

Information on urban tree growth underpins models used to calculate the effects of trees on the environment and human well-being. Maximum tree size and other growth data are used by urban forest managers, landscape architects, and planners to select trees most suitable to the amount of growing space, thereby reducing costly future conflicts between trees and...

Mosquitoes of the mangrove forests of India: part 2--Sundarbans, West Bengal.

PubMed

Rajavel, A R; Natarajan, R; Vaidyanathan, K

2005-06-01

Mosquitoes of 19 species belonging to 9 subgenera and 6 genera, Aedes, Aedeomyia, Anopheles, Armigeres, Culex, and Mansonia, were recorded in Sundarbans mangrove forest in West Bengal, India. With 6 and 5 species, respectively, the 2 genera Culex and Anopheles were found to be more diverse while less than 3 species were recorded in the other 4 genera. Adults were mainly collected resting on walls in the guesthouse, tree holes in the forest, landing on humans in the guesthouse, and in the forest, and in light traps. Larvae were obtained from tree holes in the forest. The list of species recorded is not conclusive due to the restriction in access to most parts of the mangroves due to the presence of tigers. The occurrence of the urban species Cx. quinquefasciatus within the Sajnakhali sanctuary is indicative of the need to monitor environmental changes that result with the introduction of man-made facilities.

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

Treesearch

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...

Early pest development and loss of biological control are associated with urban warming.

PubMed

Meineke, Emily K; Dunn, Robert R; Frank, Steven D

2014-11-01

Climate warming is predicted to cause many changes in ectotherm communities, one of which is phenological mismatch, wherein one species' development advances relative to an associated species or community. Phenological mismatches already lead to loss of pollination services, and we predict that they also cause loss of biological control. Here, we provide evidence that a pest develops earlier due to urban warming but that phenology of its parasitoid community does not similarly advance. This mismatch is associated with greater egg production that likely leads to more pests on trees. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Testing the air pollution tolerances of shade tree cultivars

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karnosky, D.J.

1978-01-01

A program in progress to test the relative air pollution tolerances of some commonly planted shade tree cultivars is described. The relative sulfur dioxide and ozone tolerances of several cultivars of acer, fagus, fraxinus, ginkgo, gleditsia, platanus, and quercus species are being determined by examination of foliar response to short-term, high-concentration fumigations. In a follow-up study, the extent of foliar injury, growth reduction, and mortality caused by air pollution will be examined for the same cultivars grown in test plantings in and around New York City. The correlation of the relative sulfur dioxide and ozone tolerances, as determined by themore » controlled-fumigation tests, with urban survival and growth will be useful in determining the adequacy of acute exposure fumigations in testing the air pollution tolerances of the tree species under study.« less

Influence of meteorological variables on rainfall partitioning for deciduous and coniferous tree species in urban area

NASA Astrophysics Data System (ADS)

Zabret, Katarina; Rakovec, Jože; Šraj, Mojca

2018-03-01

Rainfall partitioning is an important part of the ecohydrological cycle, influenced by numerous variables. Rainfall partitioning for pine (Pinus nigra Arnold) and birch (Betula pendula Roth.) trees was measured from January 2014 to June 2017 in an urban area of Ljubljana, Slovenia. 180 events from more than three years of observations were analyzed, focusing on 13 meteorological variables, including the number of raindrops, their diameter, and velocity. Regression tree and boosted regression tree analyses were performed to evaluate the influence of the variables on rainfall interception loss, throughfall, and stemflow in different phenoseasons. The amount of rainfall was recognized as the most influential variable, followed by rainfall intensity and the number of raindrops. Higher rainfall amount, intensity, and the number of drops decreased percentage of rainfall interception loss. Rainfall amount and intensity were the most influential on interception loss by birch and pine trees during the leafed and leafless periods, respectively. Lower wind speed was found to increase throughfall, whereas wind direction had no significant influence. Consideration of drop size spectrum properties proved to be important, since the number of drops, drop diameter, and median volume diameter were often recognized as important influential variables.

Stream ecosystems change with urban development

USGS Publications Warehouse

Bell, Amanda H.; James, F. Coles; McMahon, Gerard

2012-01-01

The healthy condition of the physical living space in a natural stream—defined by unaltered hydrology (streamflow), high diversity of habitat features, and natural water chemistry—supports diverse biological communities with aquatic species that are sensitive to disturbances. In a highly degraded urban stream, the poor condition of the physical living space—streambank and tree root damage from altered hydrology, low diversity of habitat, and inputs of chemical contaminants—contributes to biological communities with low diversity and high tolerance to disturbance.

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

EPA Science Inventory

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...

Measuring and analyzing urban tree cover

Treesearch

David J. Nowak; Rowan A. Rowntree; E. Gregory McPherson; Susan M. Sisinni; Esther R. Kirkmann; Jack C. Stevens

1996-01-01

Measurement of city tree cover can aid in urban vegetation planning, management, and research by revealing characteristics of vegetation across a city. Urban tree cover in the United States ranges from 0.4% in Lancaster, California, to 55% in Baton Rouge, Louisiana. Two important factors that affect the amount of urban tree cover are the natural environment and land...

Evaluation of Quality Parameters in Water Resource Planning. (A State-of-the-Art Survey of the Economics of Water Quality)

DTIC Science & Technology

1974-12-01

and bacteria is insufficiently known. Coliform counts are relied upon to warn of possible harm, on the assumption that pathogenic species are present...BOD, not nitrogen. Urbanization, harvesting of trees , and paving hasten the movement of nitrates from land to water. Infants are particularly...clearing, highway and building construction, adds silt and sand, gravel and rocks, branches and trees , to the natural load of sediment in rivers and lakes

Urban stress-induced biogenic VOC emissions impact secondary aerosol formation in Beijing

NASA Astrophysics Data System (ADS)

Ghirardo, A.; Xie, J.; Zheng, X.; Wang, Y.; Grote, R.; Block, K.; Wildt, J.; Mentel, T.; Kiendler-Scharr, A.; Hallquist, M.; Butterbach-Bahl, K.; Schnitzler, J.-P.

2015-08-01

Trees can significantly impact the urban air chemistry by the uptake and emission of reactive biogenic volatile organic compounds (BVOCs), which are involved in ozone and particle formation. Here we present the emission potentials of "constitutive" (cBVOCs) and "stress-induced" BVOCs (sBVOCs) from the dominant broadleaf woody plant species in the megacity of Beijing. Based on an inventory of BVOC emissions and the tree census, we assessed the potential impact of BVOCs on secondary particulate matter formation in 2005 and 2010, i.e., before and after realizing the large tree-planting program for the 2008 Olympic Games. We found that sBVOCs, such as fatty acid derivatives, benzenoids and sesquiterpenes, constituted a significant fraction (∼ 15 %) of the total annual BVOC emissions, and we estimated that the overall annual BVOC budget may have doubled from ∼ 3.6 × 109 g C year-1 in 2005 to ∼ 7.1 × 109 g C year-1 in 2010 due to the increase in urban greens, while at the same time, the emission of anthropogenic VOCs (AVOCs) could be lowered by 24 %. Based on our BVOC emission assessment, we estimated the biological impact on SOA mass formation in Beijing. Compared to AVOCs, the contribution of biogenic precursors (2-5 %) for secondary particulate matter in Beijing was low. However, sBVOCs can significantly contribute (∼ 40 %) to the formation of total secondary organic aerosol (SOA) from biogenic sources; apparently, their annual emission increased from 1.05 μg m-3 in 2005 to 2.05 μg m-3 in 2010. This study demonstrates that biogenic and, in particular, sBVOC emissions contribute to SOA formation in megacities. However, the main problems regarding air quality in Beijing still originate from anthropogenic activities. Nevertheless, the present survey suggests that in urban plantation programs, the selection of plant species with low cBVOC and sBVOC emission potentials have some possible beneficial effects on urban air quality.

The allelopathic influence of post oak (Quercus stellata) on plant species in southern U.S

Treesearch

Nicollette A. Baldwin; Michael K. Crosby

2016-01-01

Post oak (Quercus stellata) is a commonly occurring tree in the southeastern United States, offering forage and shelter for a variety of wildlife as well as having commercial uses. This species is often planted in parks and urban green-spaces for the shade it offers. Previous studies have found that parts of the plant can be toxic to livestock and...

How many trees are enough? Tree death and the urban canopy

Treesearch

Lara A. Roman

2014-01-01

Massive city tree planting campaigns have invigorated the urban forestry movement, and engaged politicians, planners, and the public in urban greening. Million tree initiatives have been launched in Los Angeles, CA; Denver, CO; New York City, NY; Philadelphia, PA, and other cities. Sacramento, CA even has a five million tree program. These...

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

Treesearch

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...

A comparison of three methods for measuring local urban tree canopy cover

Treesearch

Kristen L. King; Dexter H. Locke

2013-01-01

Measurements of urban tree canopy cover are crucial for managing urban forests and required for the quantification of the benefits provided by trees. These types of data are increasingly used to secure funding and justify large-scale planting programs in urban areas. Comparisons of tree canopy measurement methods have been conducted before, but a rapidly evolving set...

Urban tree crown health assessment system: a tool for communities and citizen foresters

Treesearch

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

2007-01-01

Trees are important assets to urban communities. In addition to the aesthetic values that urban trees provide, they also aid in such things as erosion control, pollution removal, and rainfall interception. The urban environment, however, can often produce stresses to these trees. Soil compaction, limited root growth, and groundwater contamination are just a few of the...

Dose-response of urban trees to sulfur dioxide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Temple, P.J.

1972-01-01

Controlled fumigation experiments were conducted to determine the dose-response relationships for four species of urban trees exposed to sulfur dioxide. The species chosen were ginkgo, Norway maple, pin oak, and Chinese elm. Results indicated that resistance to SO/sub 2/ increased among the species in the following order: Chinese elm, Norway maple, ginkgo, pin oak. Elm showed almost 100% leaf necrosis at exposures over 2 ppM for 6 hr, and severe chlorosis and necrosis at 0.25 ppM for 30 days. Fifty percent leaf necrosis occurred on Norway maple at 3 ppM for 6 hr, and on ginkgo at 4 ppM formore » 6 hr, and both species developed moderate marginal chlorosis at 0.50 ppM for 30 days. Injury on pin oak was minor, even at 8 ppM for 8 hr, but at 0.50 ppM for 30 days, a slight overall chlorosis developed on the leaves. The relative susceptibilities of the four species were the same in the long-term as in the short-term exposures. The shapes of the dose-response surfaces indicated that durations of exposure and concentration of the pollutant were of equal importance in producing injury on Chinese elm and probably on pin oak, but on Norway maple and ginkgo, concentration of SO/sub 2/ was of greater importance than the duration of exposure.« less

Seasonal flight activity and distribution of metallic woodboring beetles (Coleoptera: Buprestidae) collected in North Carolina and Tennessee

USDA-ARS?s Scientific Manuscript database

Metallic wood boring insects (Coleoptera: Buprestidae) species are responsible for high levels of host plant injury to deciduous shade and flowering trees in commercial nurseries, urban forests, and managed landscapes. Ornamental plant producers in the southeastern U.S. have ranked borers, includin...

Cedrus - The True Cedars

Treesearch

Paula M. Pijut

2000-01-01

The true cedars (genus Cedrus) are valuable timber trees and striking specimen plantings in the urban landscape that grow well in a variety of soil and climatic conditions. The wood is durable and decay resistant. Cedars have been successfully introduced into areas outside of their natural range. The 4 species of Cedrus, 3 of which...

Atmospheric carbon reduction by urban trees

Treesearch

David J. Nowak

1993-01-01

Trees, because they sequester atmospheric carbon through their growth process and conserve energy in urban areas, have been suggested as one means to combat increasing levels of atmospheric carbon. Analysis of the urban forest in Oakland, California (21% tree cover), reveals a tree carbon storage level of 11.0 metric tons/hectare. Trees in the area of the 1991 fire in...

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

Treesearch

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...

The leaf phenophase of deciduous species altered by land pavements

NASA Astrophysics Data System (ADS)

Chen, Yuanyuan; Wang, Xiaoke; Jiang, Bo; Li, Li

2018-06-01

It has been widely reported that the urban environment alters leaf and flowering phenophases; however, it remains unclear if land pavement is correlated with these alterations. In this paper, two popular deciduous urban trees in northern China, ash ( Fraxinus chinensis) and maple ( Acer truncatum), were planted in pervious and impervious pavements at three spacings (0.5 m × 0.5 m, 1.0 m × 1.0 m, and 2.0 m × 2.0 m apart). The beginning and end dates of the processes of leaf budburst and senescence were recorded in spring and fall of 2015, respectively. The results show that leaf budburst and senescence were significantly advanced in pavement compared to non-pavement lands. The date of full leaf budburst was earlier by 0.7-9.3 days for ash and by 0.3-2.3 days for maple under pavements than non-pavements, respectively. As tree spacing increases, the advanced days of leaf budburst became longer. Our results clearly indicate that alteration of leaf phenophases is attributed to land pavement, which should be taken into consideration in urban planning and urban plant management.

The leaf phenophase of deciduous species altered by land pavements

NASA Astrophysics Data System (ADS)

Chen, Yuanyuan; Wang, Xiaoke; Jiang, Bo; Li, Li

2018-02-01

It has been widely reported that the urban environment alters leaf and flowering phenophases; however, it remains unclear if land pavement is correlated with these alterations. In this paper, two popular deciduous urban trees in northern China, ash (Fraxinus chinensis) and maple (Acer truncatum), were planted in pervious and impervious pavements at three spacings (0.5 m × 0.5 m, 1.0 m × 1.0 m, and 2.0 m × 2.0 m apart). The beginning and end dates of the processes of leaf budburst and senescence were recorded in spring and fall of 2015, respectively. The results show that leaf budburst and senescence were significantly advanced in pavement compared to non-pavement lands. The date of full leaf budburst was earlier by 0.7-9.3 days for ash and by 0.3-2.3 days for maple under pavements than non-pavements, respectively. As tree spacing increases, the advanced days of leaf budburst became longer. Our results clearly indicate that alteration of leaf phenophases is attributed to land pavement, which should be taken into consideration in urban planning and urban plant management.

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

Treesearch

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...

A framework for adapting urban forests to climate change

Treesearch

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...

UrbanCrowns: an assessment and monitoring tool for urban trees

Treesearch

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

2011-01-01

UrbanCrowns is a Windows®-based computer program used to assess the crown characteristics of urban trees. The software analyzes side-view digital photographs of trees to compute several crown metrics, including crown height, crown diameter, live crown ratio, crown volume, crown density, and crown transparency. Potential uses of the UrbanCrowns program include...

An investigation of the leaf retention capacity, efficiency and mechanism for atmospheric particulate matter of five greening tree species in Beijing, China.

PubMed

Liu, Jinqiang; Cao, Zhiguo; Zou, Songyan; Liu, Huanhuan; Hai, Xiao; Wang, Shihua; Duan, Jie; Xi, Benye; Yan, Guangxuan; Zhang, Shaowei; Jia, Zhongkui

2018-03-01

Urban trees have the potential to reduce air pollution, but the retention capacity and efficiency of different tree species for atmospheric particulate matter (PM) accumulation and the underlying mechanism hasn't been well understood. To select tree species with high air purification abilities, the supplementing ultrasonic cleaning (UC) procedure was first introduced into the conventional leaf cleaning methods [single water cleaning (WC) or plus brush cleaning (BC)] for eluting the leaf-retained PM. Further updates to the methodology were applied to investigate the retention capacity, efficiency, and mechanism for PM of five typical greening tree species in Beijing, China. Meanwhile, the particle size distribution of PM on the leaves, the PM retention efficiencies of easily removable (ERP), difficult-to-remove (DRP) and totally removable (TRP) particles on the leaf (AE leaf ), and the individual tree scales were estimated. The experimental leaf samples were collected from trees with similar sizes 4 (SDR) and 14days (LDR) after rainfall. When the leaves were cleaned by WC+BC, there was, on average, 29%-46% of the PM remaining on the leaves of different species, which could be removed almost completely if UC was supplemented. From SDR to LDR, the mass of the leaf-retained PM increased greatly, and the particle size distribution changed markedly for all species except for Sophorajaponica. Pinus tabuliformis retains particles with the largest average diameter (34.2μm), followed by Ginkgo biloba (20.5μm), Sabina chinensis (16.4μm), Salix babylonica (16.0μm), and S. japonica (13.1μm). S. japonica and S. chinensis had the highest AE leaf to retain the TRP and ERP of both PM 1 and PM 1-2.5 , respectively. Conversely, S. babylonica and P. tabuliformis could retain both TRP and ERP of PM 2.5-5 and PM 5-10 , and PM >10 and TSP with the highest AE leaf , respectively. In conclusion, our results could be useful in selecting greening tree species with high air purification abilities. Copyright © 2017 Elsevier B.V. All rights reserved.

Simulating Urban Tree Effects on Air, Water, and Heat Pollution Mitigation: iTree-Hydro Model

NASA Astrophysics Data System (ADS)

Yang, Y.; Endreny, T. A.; Nowak, D.

2011-12-01

Urban and suburban development changes land surface thermal, radiative, porous, and roughness properties and pollutant loading rates, with the combined effect leading to increased air, water, and heat pollution (e.g., urban heat islands). In this research we present the USDA Forest Service urban forest ecosystem and hydrology model, iTree Eco and Hydro, used to analyze how tree cover can deliver valuable ecosystem services to mitigate air, water, and heat pollution. Air pollution mitigation is simulated by dry deposition processes based on detected pollutant levels for CO, NO2, SO2, O3 and atmospheric stability and leaf area indices. Water quality mitigation is simulated with event mean concentration loading algorithms for N, P, metals, and TSS, and by green infrastructure pollutant filtering algorithms that consider flow path dispersal areas. Urban cooling considers direct shading and indirect evapotranspiration. Spatially distributed estimates of hourly tree evapotranspiration during the growing season are used to estimate human thermal comfort. Two main factors regulating evapotranspiration are soil moisture and canopy radiation. Spatial variation of soil moisture is represented by a modified urban topographic index and radiation for each tree is modified by considering aspect, slope and shade from surrounding buildings or hills. We compare the urban cooling algorithms used in iTree-Hydro with the urban canopy and land surface physics schemes used in the Weather Research and Forecasting model. We conclude by identifying biophysical feedbacks between tree-modulated air and water quality environmental services and how these may respond to urban heating and cooling. Improvements to this iTree model are intended to assist managers identify valuable tree services for urban living.

Modeling individual trees in an urban environment using dense discrete return LIDAR

NASA Astrophysics Data System (ADS)

Bandyopadhyay, Madhurima; van Aardt, Jan A. N.; van Leeuwen, Martin

2015-05-01

The urban forest is becoming increasingly important in the contexts of urban green space, carbon sequestration and offsets, and socio-economic impacts. This has led to a recent increase in attention being paid to urban environmental management. Tree biomass, specifically, is a vital indicator of carbon storage and has a direct impact on urban forest health and carbon sequestration. As an alternative to expensive and time-consuming field surveys, remote sensing has been used extensively in measuring dynamics of vegetation and estimating biomass. Light detection and ranging (LiDAR) has proven especially useful to characterize the three dimensional (3D) structure of forests. In urban contexts however, information is frequently required at the individual tree level, necessitating the proper delineation of tree crowns. Yet, crown delineation is challenging for urban trees where a wide range of stress factors and cultural influences affect growth. In this paper high resolution LiDAR data were used to infer biomass based on individual tree attributes. A multi-tiered delineation algorithm was designed to extract individual tree-crowns. At first, dominant tree segments were obtained by applying watershed segmentation on the crown height model (CHM). Next, prominent tree top positions within each segment were identified via a regional maximum transformation and the crown boundary was estimated for each of the tree tops. Finally, undetected trees were identified using a best-fitting circle approach. After tree delineation, individual tree attributes were used to estimate tree biomass and the results were validated with associated field mensuration data. Results indicate that the overall tree detection accuracy is nearly 80%, and the estimated biomass model has an adjusted-R2 of 0.5.

Compensatory value of urban trees in the United States

Treesearch

David J. Nowak; Daniel E. Crane; John F. Dwyer

2002-01-01

Understanding the value of an urban forest can give decision makers a better foundation for urban tree namagement. Based on tree-valuation methods of the Council of Tree and Landscape Appraisers and field data from eight cities, total compensatory value of tree populations in U.S. cities ranges from $101 million in Jersey City, New Jersey, to $6.2 billion in New York,...

Failure mechanism of hollow tree trunks due to cross-sectional flattening

PubMed Central

Huang, Yan-San; Hsu, Fu-Lan; Lee, Chin-Mei

2017-01-01

Failure of hollow trees in urban areas is a worldwide concern, and it can be caused by different mechanisms, i.e. bending stresses or flattening-related failures. Here we derive a new analytical expression for predicting the bending moment for tangential cracking, and compare the breaking moment of various failure modes, including Brazier buckling, tangential cracking, shear failure and conventional bending failure, as a function of t/R ratio, where t and R are the trunk wall thickness and trunk radius, respectively, of a hollow tree. We use Taiwan red cypress as an example and show that its failure modes and the corresponding t/R ratios are: Brazier buckling (Mode I), tangential cracking followed by longitudinal splitting (Mode II) and conventional bending failure (Mode III) for 0 < t/R < 0.06, 0.06 < t/R < 0.27 and 0.27 < t/R < 1, respectively. The exact values of those ratios may vary within and among species, but the variation is much smaller than individual mechanical properties. Also, shear failure, another type of cracking due to maximum shear stress near the neutral axis of the tree trunk, is unlikely to occur since it requires much larger bending moments. Hence, we conclude that tangential cracking due to cross-sectional flattening, followed by longitudinal splitting, is dominant for hollow trunks. Our equations are applicable to analyse straight hollow tree trunks and plant stems, but are not applicable to those with side openings or those with only heart decay. Our findings provide insights for those managing trees in urban situations and those managing for conservation of hollow-dependent fauna in both urban and rural settings. PMID:28484616

Genetic differences between yellowwood (Cladrastis kentukea) in wild populations versus urban forests

Treesearch

N.R. LaBonte; K.E. Woeste

2017-01-01

Yellowwood (Cladrastis kentukea) is an uncommon, relict, tree species with a disjunct distribution primarily in the Central Hardwoods region. Most common on rocky, sheltered slopes of the Cumberland Plateau in Tennessee and Kentucky, isolated populations occur on appropriate sites throughout the southern and central United States. In Illinois,...

Changes In Tree Species In Riparian Zones Of Urban Streams May Have Effects On Restoration And Storm Water Control Efforts

EPA Science Inventory

A riparian zone is the land and vegetation within and directly adjacent to surface water ecosystems, such as lakes and streams. The vegetation in riparian zones provides ecosystem services (such as reducing flooding and bank erosion and reducing levels of pollutants in streams) ...

Tree Canopy Cover Mapping Using LiDAR in Urban Barangays of Cebu City, Central Philippines

NASA Astrophysics Data System (ADS)

Ejares, J. A.; Violanda, R. R.; Diola, A. G.; Dy, D. T.; Otadoy, J. B.; Otadoy, R. E. S.

2016-06-01

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.

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

NASA Astrophysics Data System (ADS)

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 (<1m). These metrics are essential for modeling the HVAC benefits from UTC for individual homes, and for assessing the ecosystem services for entire urban areas. Such maps have previously been made using a variety of methods, typically relying on high resolution aerial or satellite imagery. This paper seeks to contribute to this growing 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.

Where to plant urban trees? A spatially explicit methodology to explore ecosystem service tradeoffs

Treesearch

E.W. Bodnaruk; C.N. Kroll; Y. Yang; S. Hirabayashi; David Nowak; T.A. Endreny

2017-01-01

Urban trees can help mitigate some of the environmental degradation linked to the rapid urbanization of humanity. Many municipalities are implementing ambitious tree planting programs to help remove air pollution, mitigate urban heat island effects, and provide other ecosystem services and benefits but lack quantitative tools to explore priority planting locations and...

A modeling study of the impact of urban trees on ozone

Treesearch

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...

Homeowner interactions with residential trees in urban areas

Treesearch

Jana Dilley; Kathleen L. Wolf

2013-01-01

Urban forests are a critical element in sustainable urban areas because of the many environmental, economic, and social benefits that city trees provide. In order to increase canopy cover in urban areas, residential homeowners, who collectively own the majority of the land in most cities, need to engage in planting and retaining trees on their properties. This...

The role of vegetation in the CO2 flux from a tropical urban neighbourhood

NASA Astrophysics Data System (ADS)

Velasco, E.; Roth, M.; Tan, S. H.; Quak, M.; Nabarro, S. D. A.; Norford, L.

2013-03-01

Urban surfaces are usually net sources of CO2. Vegetation can potentially have an important role in reducing the CO2 emitted by anthropogenic activities in cities, particularly when vegetation is extensive and/or evergreen. Negative daytime CO2 fluxes, for example have been observed during the growing season at suburban sites characterized by abundant vegetation and low population density. A direct and accurate estimation of carbon uptake by urban vegetation is difficult due to the particular characteristics of the urban ecosystem and high variability in tree distribution and species. Here, we investigate the role of urban vegetation in the CO2 flux from a residential neighbourhood in Singapore using two different approaches. CO2 fluxes measured directly by eddy covariance are compared with emissions estimated from emissions factors and activity data. The latter includes contributions from vehicular traffic, household combustion, soil respiration and human breathing. The difference between estimated emissions and measured fluxes should approximate the biogenic flux. In addition, a tree survey was conducted to estimate the annual CO2 sequestration using allometric equations and an alternative model of the metabolic theory of ecology for tropical forests. Palm trees, banana plants and turfgrass were also included in the survey with their annual CO2 uptake obtained from published growth rates. Both approaches agree within 2% and suggest that vegetation captures 8% of the total emitted CO2 in the residential neighbourhood studied. A net uptake of 1.4 ton km-2 day-1 (510 ton km-2 yr-1 ) was estimated from the difference between the daily CO2 uptake by photosynthesis (3.95 ton km-2 ) and release by respiration (2.55 ton km-2). The study shows the importance of urban vegetation at the local scale for climate change mitigation in the tropics.

Urban park tree inventories

Treesearch

Joe R. McBride; David J. Nowak

1989-01-01

A survey of published reports on urban park tree inventories in the United States and the United Kingdom reveal two types of inventories: (1) Tree Location Inventories and (2) Generalized Information Inventories. Tree location inventories permit managers to relocate specific park trees, along with providing individual tree characteristics and condition data. In...

Measuring urban tree loss dynamics across residential landscapes.

PubMed

Ossola, Alessandro; Hopton, Matthew E

2018-01-15

The spatial arrangement of urban vegetation depends on urban morphology and socio-economic settings. Urban vegetation changes over time because of human management. Urban trees are removed due to hazard prevention or aesthetic preferences. Previous research attributed tree loss to decreases in canopy cover. However, this provides little information about location and structural characteristics of trees lost, as well as environmental and social factors affecting tree loss dynamics. This is particularly relevant in residential landscapes where access to residential parcels for field surveys is limited. We tested whether multi-temporal airborne LiDAR and multi-spectral imagery collected at a 5-year interval can be used to investigate urban tree loss dynamics across residential landscapes in Denver, CO and Milwaukee, WI, covering 400,705 residential parcels in 444 census tracts. Position and stem height of trees lost were extracted from canopy height models calculated as the difference between final (year 5) and initial (year 0) vegetation height derived from LiDAR. Multivariate regression models were used to predict number and height of tree stems lost in residential parcels in each census tract based on urban morphological and socio-economic variables. A total of 28,427 stems were lost from residential parcels in Denver and Milwaukee over 5years. Overall, 7% of residential parcels lost one stem, averaging 90.87 stems per km 2 . Average stem height was 10.16m, though trees lost in Denver were taller compared to Milwaukee. The number of stems lost was higher in neighborhoods with higher canopy cover and developed before the 1970s. However, socio-economic characteristics had little effect on tree loss dynamics. The study provides a simple method for measuring urban tree loss dynamics within and across entire cities, and represents a further step toward high resolution assessments of the three-dimensional change of urban vegetation at large spatial scales. Published by Elsevier B.V.

Assessing the Capacity of Plant Species to Accumulate Particulate Matter in Beijing, China

PubMed Central

Mo, Li; Ma, Zeyu; Xu, Yansen; Sun, Fengbin; Lun, Xiaoxiu; Liu, Xuhui; Chen, Jungang; Yu, Xinxiao

2015-01-01

Air pollution causes serious problems in spring in northern China; therefore, studying the ability of different plants to accumulate particulate matter (PM) at the beginning of the growing season may benefit urban planners in their attempts to control air pollution. This study evaluated deposits of PM on the leaves and in the wax layer of 35 species (11 shrubs, 24 trees) in Beijing, China. Differences in the accumulation of PM were observed between species. Cephalotaxus sinensis, Euonymus japonicus, Broussonetia papyriferar, Koelreuteria paniculata and Quercus variabilis were all efficient in capturing small particles. The plants exhibiting high amounts of total PM accumulation (on leaf surfaces and/or in the wax layer), also showed comparatively high levels of PM accumulation across all particle sizes. A comparison of shrubs and trees did not reveal obvious differences in their ability to accumulate particles based on growth form; a combination of plantings with different growth forms can efficiently reduce airborne PM concentrations near the ground. To test the relationships between leaf traits and PM accumulation, leaf samples of selected species were observed using a scanning electron microscope. Growth forms with greater amounts of pubescence and increased roughness supported PM accumulation; the adaxial leaf surfaces collected more particles than the abaxial surfaces. The results of this study may inform the selection of species for urban green areas where the goal is to capture air pollutants and mitigate the adverse effects of air pollution on human health. PMID:26506104

Parachuting behavior and predation by ants in the nettle caterpillar, Scopelodes contracta.

PubMed

Yamazaki, Kazuo

2010-01-01

This paper documents the bizarre descending behavior from the tree crown to the ground of the larvae of the moth, Scopelodes contracta Walker (Lepidoptera: Limacodidae) and the interaction of the larva with predatory ants. S. contracta larvae infest leaves of many tree species in urban areas and orchards in Japan. Mature larvae and leaves without basal leaf parts were found under trees of four species infested with S. contracta larvae in Osaka, Japan. Individual larvae riding on leaves were observed falling from tree crowns to the ground. Many S. contracta cocoons were found in the soil below the trees two weeks after the observed parachuting. These observations indicate that S. contracta larvae parachuted to the ground where they spin their cocoons in the soil. When a larva that had just parachuted down was returned to an arboreal twig, the larva repeated the parachuting behavior. This parachuting behavior appears to be adaptive, because larvae can descend to the ground safely and with low energy cost. Worker ants of Tetramorium tsushimae Emery (Hymenoptera: Formicidae) and Pristomyrmex punctatus Mayr (Hymenoptera: Formicidae) occasionally attacked larvae on the ground before they had a chance to burrow in the soil.

Trees and Streets as Drivers of Urban Stormwater Nutrient Pollution.

PubMed

Janke, Benjamin D; Finlay, Jacques C; Hobbie, Sarah E

2017-09-05

Expansion of tree cover is a major management goal in cities because of the substantial benefits provided to people, and potentially to water quality through reduction of stormwater volume by interception. However, few studies have addressed the full range of potential impacts of trees on urban runoff, which includes deposition of nutrient-rich leaf litter onto streets connected to storm drains. We analyzed the influence of trees on stormwater nitrogen and phosphorus export across 19 urban watersheds in Minneapolis-St. Paul, MN, U.S.A., and at the scale of individual streets within one residential watershed. Stormwater nutrient concentrations were highly variable across watersheds and strongly related to tree canopy over streets, especially for phosphorus. Stormwater nutrient loads were primarily related to road density, the dominant control over runoff volume. Street canopy exerted opposing effects on loading, where elevated nutrient concentrations from trees near roads outweighed the weak influence of trees on runoff reduction. These results demonstrate that vegetation near streets contributes substantially to stormwater nutrient pollution, and therefore to eutrophication of urban surface waters. Urban landscape design and management that account for trees as nutrient pollution sources could improve water quality outcomes, while allowing cities to enjoy the myriad benefits of urban forests.

Botryosphaeriaceae associated with the die-back of ornamental trees in the Western Balkans.

PubMed

Zlatković, Milica; Keča, Nenad; Wingfield, Michael J; Jami, Fahimeh; Slippers, Bernard

2016-04-01

Extensive die-back and mortality of various ornamental trees and shrubs has been observed in parts of the Western Balkans region during the past decade. The disease symptoms have been typical of those caused by pathogens residing in the Botryosphaeriaceae. The aims of this study were to isolate and characterize Botryosphaeriaceae species associated with diseased ornamental trees in Serbia, Montenegro, Bosnia and Herzegovina. Isolates were initially characterized based on the DNA sequence data for the internal transcribed spacer rDNA and six major clades were identified. Representative isolates from each clade were further characterized using DNA sequence data for the translation elongation factor 1-alpha, β-tubulin-2 and large subunit rRNA gene regions, as well as the morphology of the asexual morphs. Ten species of the Botryosphaeriaceae were identified of which eight, i.e., Dothiorella sarmentorum, Neofusicoccum parvum, Botryosphaeria dothidea, Phaeobotryon cupressi, Sphaeropsis visci, Diplodia seriata, D. sapinea and D. mutila were known taxa. The remaining two species could be identified only as Dothiorella spp. Dichomera syn-asexual morphs of D. sapinea, Dothiorella sp. 2 and B. dothidea, as well as unique morphological characters for a number of the known species are described. Based on host plants and geographic distribution, the majority of Botryosphaeriaceae species found represent new records. The results of this study contribute to our knowledge of the distribution, host associations and impacts of these fungi on trees in urban environments.

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

PubMed

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

NASA Astrophysics Data System (ADS)

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.

Monitoring the Urban Tree Cover for Urban Ecosystem Services - The Case of Leipzig, Germany

NASA Astrophysics Data System (ADS)

Banzhaf, E.; Kollai, H.

2015-04-01

Urban dynamics such as (extreme) growth and shrinkage bring about fundamental challenges for urban land use and related changes. In order to achieve a sustainable urban development, it is crucial to monitor urban green infrastructure at microscale level as it provides various urban ecosystem services in neighbourhoods, supporting quality of life and environmental health. We monitor urban trees by means of a multiple data set to get a detailed knowledge on its distribution and change over a decade for the entire city. We have digital orthophotos, a digital elevation model and a digital surface model. The refined knowledge on the absolute height above ground helps to differentiate tree tops. Grounded on an object-based image analysis scheme a detailed mapping of trees in an urbanized environment is processed. Results show high accuracy of tree detection and avoidance of misclassification due to shadows. The study area is the City of Leipzig, Germany. One of the leading German cities, it is home to contiguous community allotments that characterize the configuration of the city. Leipzig has one of the most well-preserved floodplain forests in Europe.

Water requirements of honeylocust (Gleditsia triacanthos f. inermis) in the urban forest

Treesearch

Howard G. Halverson; Donald F. Potts

1981-01-01

Water use by an urban tree was measured lysimetrically while water use by the same tree at a non-urban site was estimated by a model. Comparison of the measured and estimated water use showed that the urban honeylocust (Gleditsia triacanthos f. inermis) required an average of 155 percent of the water needed by the same tree...

Microhabitats occupied by Loxosceles intermedia and Loxosceles laeta (Araneae: Sicariidae) in Curitiba, Paraná, Brazil.

PubMed

Fischer, Marta Luciane; Vasconcellos-Neto, João

2005-09-01

A survey was done of the environments and substrata occupied by Loxosceles intermedia Mello-Leitão, 1934 and Loxosceles laeta (Nicolet, 1849) (Araneae: Sicariidae) in urban woods and anthropic constructions in Curitiba. In total, 2,099 trees, 364 decaying logs as well as stones and roots, built-up areas, and wasteland in six urban parks and 60 residences were inspected. In total, 1,775 m2 of vegetation was inspected, but spiders and their vestiges were collected only in and around buildings in urban parks and residences. L. intermedia was more common than L. laeta and occurred both indoors and outdoors, whereas L. laeta was more common indoors in wooden houses. The two species did not occur in the same microhabitats, although both preferred paper, wood, and construction materials. Spiders collected in urban parks were heavier than those collected in residences, although only males collected in urban parks were larger than those from residences. The lack of vestiges indicative of a previous occupation in the urban parks suggested that both species occupied primarily the anthropic environment where they found numerous substrata that offered thermal isolation and suitable conditions for web fixation, ecdysis, and reproduction.

Canopy rainfall partitioning across an urbanization gradient in forest structure as characterized by terrestrial LiDAR

NASA Astrophysics Data System (ADS)

Mesta, D. C.; Van Stan, J. T., II; Yankine, S. A.; Cote, J. F.; Jarvis, M. T.; Hildebrandt, A.; Friesen, J.; Maldonado, G.

2017-12-01

As urbanization expands, greater forest area is shifting from natural stand structures to urban stand structures, like forest fragments and landscaped tree rows. Changes in forest canopy structure have been found to drastically alter the amount of rainwater reaching the surface. However, stormwater management models generally treat all forest structures (beyond needle versus broadleaved) similarly. This study examines the rainfall partitioning of Pinus spp. canopies along a natural-to-urban forest gradient and compares these to canopy structural measurements using terrestrial LiDAR. Throughfall and meteorological observations were also used to estimate parameters of the commonly-used Gash interception model. Preliminary findings indicate that as forest structure changed from natural, closed canopy conditions to semi-closed canopy fragments and, ultimately, to exposed urban landscaping tree rows, the interchange between throughfall and rainfall interception also changed. This shift in partitioning between throughfall and rainfall interception may be linked to intuitive parameters, like canopy closure and density, as well as more complex metrics, like the fine-scale patterning of gaps (ie, lacunarity). Thus, results indicate that not all forests of the same species should be treated the same by stormwater models. Rather, their canopy structural characteristics should be used to vary their hydrometeorological interactions.

Urban Forest Ecosystem Service Optimization, Tradeoffs, and Disparities

NASA Astrophysics Data System (ADS)

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.

A novel disease of big-leaf mahogany caused by two Fusarium species in Mexico

USDA-ARS?s Scientific Manuscript database

Swietenia macrophylla is valued for its high-quality wood and use in urban landscapes in Mexico. During surveys of mango-producing areas in the central western region of Mexico, symptoms of malformation, the most important disease of mango in the area, were observed on big-leaf mahogany trees. The o...

Urban Forestry Laboratory Exercises (For Elementary, Middle, and High School)

Treesearch

USDA Forest Service

1998-01-01

The development of the Urban Forest is fast becoming a major concern. The population shift in our country from rural to urban is undeniable. People see trees as a barrier to the hot summer sun and harsh winter winds. They see trees as a source of natural aesthetic beauty. Trees are a resource for the renewal of inner peace and health. Trees are landscape essentials,...

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

Treesearch

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...

[Allergic responses to date palm and pecan pollen in Israel].

PubMed

Waisel, Y; Keynan, N; Gil, T; Tayar, D; Bezerano, A; Goldberg, A; Geller-Bernstein, C; Dolev, Z; Tamir, R; Levy, I

1994-03-15

Date palm (Phoenix dactylifera) and pecan (Carya illinoensis) trees are commonly planted in Israel for fruit, for shade, or as ornamental plants. Pollen grains of both species are allergenic; however, the extent of exposure to such pollen and the incidence of allergic response have not been studied here. We therefore investigated skin-test responses to pollen extracts of 12 varieties of palm and 9 of pecan in 705 allergic patients living in 3 cities and 19 rural settlements. Sensitivity to the pollen extracts of both species was much higher among residents of rural than of urban communities. Moreover, there was a definite relationship between the abundance of these trees in a region and the incidence of skin responders to their pollen. Sensitivity was frequent in settlements rich in these 2 species, such as those with nearby commercial date or pecan plantations. In general, sensitivity to date pollen extracts was lower than to pecan. However, differences in skin responses to pollen extracts of various clones were substantiated. Air sampling revealed that pollen pollution decreased considerably with distance from the trees. At approximately 100 m from a source concentrations of airborne pollen were low. Since planting of male palm and pecan trees in population centers would increase pollen pollution, it should be avoided.

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

Treesearch

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-...

Urban Sacramento oak reforestation: 17 years and 20,000 trees

Treesearch

Zarah Wyly; Erika Teach

2015-01-01

The Sacramento Tree Foundation (Tree Foundation), a nonprofit organization operating in the greater Sacramento California region, has been engaged in planting native oak trees in urban and suburban areas since 1998. Through an effort to provide efficient access to tree mitigation services and support compliance with local tree protection ordinances, more than 20,038...

Criterion 8: Urban and community forests

Treesearch

Stephen R. Shifley; Francisco X. Aguilar; Nianfu Song; Susan I. Stewart; David J. Nowak; Dale D. Gormanson; W. Keith Moser; Sherri Wormstead; Eric J. Greenfield

2012-01-01

Urban and community forests are the trees and forests found in cities, towns, villages, and communities. This category of forest includes both forested stands and trees along streets, in residential lots, and parks. These trees within cities and communities provide many ecosystem services and values to both urban and rural populations.

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

NASA Technical Reports Server (NTRS)

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.

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

NASA Astrophysics Data System (ADS)

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 grows internationally, environmental databases from more countries will be coupled with the software suite. Two more i-Tree applications, i-Tree Forecast and i-Tree Landscape are now under development. i-Tree Forecast simulates canopy structures for up to 100 years based on planting and mortality rates and adds capabilities for other i-Tree applications to estimate the benefits of future canopy scenarios. While most i-Tree applications employ a spatially lumped approach, i-Tree landscape employs a spatially distributed approach that allows users to map changes in canopy cover and ecosystem services through time and space. These new i-Tree tools provide an advanced platform for urban managers to assess the impact of current and future urban forests. i-Tree allows managers to promote effective urban forest management and sound arboricultural practices by providing information for advocacy and planning, baseline data for making informed decisions, and standardization for comparisons with other communities.

National Forest Health Monitoring Program Wisconsin Street Tree Assessment 2002-2003, NA-FR-02-08 Brief

Treesearch

Anne Buckelew Cumming; Daniel Twardus; Robert Hoehn; David Nowak; Manfred Mielke; Richard Rideout; Helen Butalla; Patricia Lebow

2008-01-01

Street trees grow along roadways within the public right-ofway. They are an important part of the urban forest due to their visibility to motorists and pedestrians, even if their numbers represent a small fraction of trees in urban areas. Little data are available that describe this resource at a large, statewide scale. Street trees, a subpopulation of the urban forest...

Estimating Carbon Storage and Sequestration by Urban Trees at Multiple Spatial Resolutions

NASA Astrophysics Data System (ADS)

Wu, J.; Tran, A.; Liao, A.

2010-12-01

Urban forests are an important component of urban-suburban environments. Urban trees provide not only a full range of social and psychological benefits to city dwellers, but also valuable ecosystem services to communities, such as removing atmospheric carbon dioxide, improving air quality, and reducing storm water runoff. There is an urgent need for developing strategic conservation plans for environmentally sustainable urban-suburban development based on the scientific understanding of the extent and function of urban forests. However, several challenges remain to accurately quantify various environmental benefits provided by urban trees, among which is to deal with the effect of changing spatial resolution and/or scale. In this study, we intended to examine the uncertainties of carbon storage and sequestration associated with the tree canopy coverage of different spatial resolutions. Multi-source satellite imagery data were acquired for the City of Fullerton, located in Orange County of California. The tree canopy coverage of the study area was classified at three spatial resolutions, ranging from 30 m (Landsat-5 Thematic Mapper), 15 m (Advanced Spaceborne Thermal Emission and Reflection Radiometer), to 2.5 m (QuickBird). We calculated the amount of carbon stored in the trees represented on the individual tree coverage maps and the annual carbon taken up by the trees with a model (i.e., CITYgreen) developed by the U.S. Forest Service. The results indicate that urban trees account for significant proportions of land cover in the study area even with the low spatial resolution data. The estimated carbon fixation benefits vary greatly depending on the details of land use and land cover classification. The extrapolation of estimation from the fine-resolution stand-level to the low-resolution landscape-scale will likely not preserve reasonable accuracy.

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

NASA Astrophysics Data System (ADS)

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.

Responses of fungal and plant communities to partial humus removal in mid-boreal N-enriched forests.

PubMed

Tarvainen, Oili; Hamberg, Leena; Ohenoja, Esteri; Strömmer, Rauni; Markkola, Annamari

2012-10-15

Partial removal of the forest humus layer was performed in nitrogen-enriched urban Scots pine forest stands in the northern Finland in order to improve soil conditions for ectomycorrhizal (ECM) fungi, important symbionts of trees. Aboveground part of understory vegetation and the uppermost half of the humus layer were removed (REMOVAL treatment) from sample plots in six urban and eight rural reference forest sites at the beginning of the 2001 growing season. During the seasons 2001-2005, we inventoried sporocarp production of ECM and saprophytic fungi, and in 2003 the recovery of understory vegetation. The REMOVAL treatment resulted in a higher number of fruiting ECM species and sporocarps than controls at the rural, but not at urban sites. The sporocarp number of saprophytic fungi declined in the REMOVAL subplots at the urban sites. The recovery of bryophytes and lichens in the REMOVAL treatment was slow at both the urban and rural sites, whereas Vaccinium dwarf shrub cover, and herb and grass cover returned rapidly at the urban sites. We conclude that the partial vegetation and humus layer removal as a tool to promote the reproduction of ECM fungal species is limited in the boreal urban forests. Copyright © 2012 Elsevier Ltd. All rights reserved.

Bat use of a high-plains urban wildlife refuge

USGS Publications Warehouse

Everette, A.L.; O'Shea, T.J.; Ellison, L.E.; Stone, L.A.; McCance, J.L.

2001-01-01

Bats are significant components of mammalian diversity and in many areas are of management concern. However, little attention has been given to bats in urban or prairie landscapes. In 1997 and 1998, we determined species richness, relative abundance, roosting habits, and echolocation activity of bats at Rocky Mountain Arsenal National Wildlife Refuge (RMA), the largest urban unit in the United States refuge system, located on the high plains near Denver, Colorado. An inventory using mist nets revealed 3 species foraging at this site: big brown bats (Eptesicus fuscus), hoary bats (Lasiurus cinereus), and silver-haired bats (Lasionycteris noctivagans). Big brown bats comprised 86% of captures (n=176). This pattern was consistent with continental-scale predictions of bat species richness and evenness based on availability of potential roosts. Relative abundance based on captures was similar to that revealed by echolocation detector surveys, except that the latter revealed the likely presence of at least 2 additional species (Myotis spp. and red bats [Lasiurus borealis]). Echolocation activity was significantly greater (P=0.009) in areas with tree or water habitat edges than in open prairie, suggesting that maintaining such features is important for bats. Big brown bats commuted greater distances (9.2-18.8 km) from roosts in urban core areas to foraging sites on the refuge than typically reported for this species elsewhere, emphasizing the value of the site to these bats. Urban refuges can provide habitat of importance to bat populations, but may be characterized by abundant bats that roost in buildings if a variety of other kinds of roosting habitats are unavailable.

Coptoborus ochromactonus, n. sp. (Coleoptera: Curculionidae: Scolytinae), an emerging pest of cultivated balsa (Malvales: Malvaceae) in Ecuador.

PubMed

Stilwell, Abby R; Smith, Sarah M; Cognato, Anthony I; Martinez, Malena; Flowers, R Wills

2014-04-01

A new species of xyleborine ambrosia beetle has been found to attack balsa, Ochroma pyramidale (Cavanilles ex Lamarck) Urban, in Ecuador. Coptoborus ochromactonus Smith & Cognato is described and its biology is reported. Large-scale surveys were conducted between 2006 and 2009, and observational studies were carried out between 2010 and 2013 in Ecuadorian commercial plantations to determine life history and host preference characteristics. C. ochromactonus attacked balsa between 1.5 and 3 yr in age. Successful attacks were more prevalent in smaller diameter trees and unhealthy trees. In general, attacks and beetle-caused mortality were more prevalent during the dry summer months when trees were under more moisture and light stress. Fungal mycelia were consistently observed coating beetle galleries and are likely the true damaging agent to balsa trees.

The Early Detection of the Emerald Ash Borer (EAB) Using Advanced Geospacial Technologies

NASA Astrophysics Data System (ADS)

Hu, B.; Li, J.; Wang, J.; Hall, B.

2014-11-01

The objectives of this study were to exploit Light Detection And Ranging (LiDAR) and very high spatial resolution (VHR) data and their synergy with hyperspectral imagery in the early detection of the EAB presence in trees within urban areas and to develop a framework to combine information extracted from multiple data sources. To achieve these, an object-oriented framework was developed to combine information derived from available data sets to characterize ash trees. Within this framework, individual trees were first extracted and then classified into different species based on their spectral information derived from hyperspectral imagery, spatial information from VHR imagery, and for each ash tree its health state and EAB infestation stage were determined based on hyperspectral imagery. The developed framework and methods were demonstrated to be effective according to the results obtained on two study sites in the city of Toronto, Ontario Canada. The individual tree delineation method provided satisfactory results with an overall accuracy of 78 % and 19 % commission and 23 % omission errors when used on the combined very high-spatial resolution imagery and LiDAR data. In terms of the identification of ash trees, given sufficient representative training data, our classification model was able to predict tree species with above 75 % overall accuracy, and mis-classification occurred mainly between ash and maple trees. The hypothesis that a strong correlation exists between general tree stress and EAB infestation was confirmed. Vegetation indices sensitive to leaf chlorophyll content derived from hyperspectral imagery can be used to predict the EAB infestation levels for each ash tree.

Multi-Scale, Direct and Indirect Effects of the Urban Stream Syndrome on Amphibian Communities in Streams

PubMed Central

Canessa, Stefano; Parris, Kirsten M.

2013-01-01

Urbanization affects streams by modifying hydrology, increasing pollution and disrupting in-stream and riparian conditions, leading to negative responses by biotic communities. Given the global trend of increasing urbanization, improved understanding of its direct and indirect effects at multiple scales is needed to assist management. The theory of stream ecology suggests that the riverscape and the surrounding landscape are inextricably linked, and watershed-scale processes will also affect in-stream conditions and communities. This is particularly true for species with semi-aquatic life cycles, such as amphibians, which transfer energy between streams and surrounding terrestrial areas. We related measures of urbanization at different scales to frog communities in streams along an urbanization gradient in Melbourne, Australia. We used boosted regression trees to determine the importance of predictors and the shape of species responses. We then used structural equation models to investigate possible indirect effects of watershed imperviousness on in-stream parameters. The proportion of riparian vegetation and road density surrounding the site at the reach scale (500-m radius) had positive and negative effects, respectively, on species richness and on the occurrence of the two most common species in the area ( Crinia signifera and Limnodynastesdumerilii ). Road density and local aquatic vegetation interacted in influencing species richness, suggesting that isolation of a site can prevent colonization, in spite of apparently good local habitat. Attenuated imperviousness at the catchment scale had a negative effect on local aquatic vegetation, indicating possible indirect effects on frog species not revealed by single-level models. Processes at the landscape scale, particularly related to individual ranging distances, can affect frog species directly and indirectly. Catchment imperviousness might not affect adult frogs directly, but by modifying hydrology it can disrupt local vegetation and prove indirectly detrimental. Integrating multiple-scale management actions may help to meet conservation targets for streams in the face of urbanization. PMID:23922963

Declining urban and community tree cover in the United States

Treesearch

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...

Taxonomic and phylogenetic diversity of vascular plants at Ma'anling volcano urban park in tropical Haikou, China: Reponses to soil properties.

PubMed

Cheng, Xia-Lan; Yuan, Lang-Xing; Nizamani, Mir Mohammad; Zhu, Zhi-Xin; Friedman, Cynthia Ross; Wang, Hua-Feng

2018-01-01

Anthropogenic processes and socio-economic factors play important roles in shaping plant diversity in urban parks. To investigate how plant diversity of Ma' anling urban volcano park in Hainan Province, China respond to these factors, we carried out a field investigation on the taxonomic and phylogenetic diversity of vascular plants and soil properties in this area. We found 284 species of vascular plants belonging to 88 families and 241 genera, which included 194 native species, 23 invasive species, 31 naturalized species, 40 cultivars, and 4 rare / endangered plant species. Tree composition and richness significantly varied between different vegetation formations (plantation, secondary forest, and abandoned land). Plant species richness and community composition were significantly affected by elevation (El), soil water content (WC), total soil nitrogen (TN) and soil organic matter (SOM). There were significant diversity differences between plantations and abandoned lands, but not between the plantations and secondary forests. The flora in the study site was tropical in nature, characterized by pantropic distributions. Compared to adjacent areas, floristic composition in the study site was most similar to that of Guangdong, followed by that of Vietnam. Our study revealed the diversity patterns of volcanic plants and provided the basis for future planning of plant conservation, such as preserving plant species, maintaining plant habitats, and coordinating plant management in this region.

Insectivorous bats respond to vegetation complexity in urban green spaces.

PubMed

Suarez-Rubio, Marcela; Ille, Christina; Bruckner, Alexander

2018-03-01

Structural complexity is known to determine habitat quality for insectivorous bats, but how bats respond to habitat complexity in highly modified areas such as urban green spaces has been little explored. Furthermore, it is uncertain whether a recently developed measure of structural complexity is as effective as field-based surveys when applied to urban environments. We assessed whether image-derived structural complexity (MIG) was as/more effective than field-based descriptors in this environment and evaluated the response of insectivorous bats to structural complexity in urban green spaces. Bat activity and species richness were assessed with ultrasonic devices at 180 locations within green spaces in Vienna, Austria. Vegetation complexity was assessed using 17 field-based descriptors and by calculating the mean information gain (MIG) using digital images. Total bat activity and species richness decreased with increasing structural complexity of canopy cover, suggesting maneuverability and echolocation (sensorial) challenges for bat species using the canopy for flight and foraging. The negative response of functional groups to increased complexity was stronger for open-space foragers than for edge-space foragers. Nyctalus noctula , a species foraging in open space, showed a negative response to structural complexity, whereas Pipistrellus pygmaeus , an edge-space forager, was positively influenced by the number of trees. Our results show that MIG is a useful, time- and cost-effective tool to measure habitat complexity that complemented field-based descriptors. Response of insectivorous bats to structural complexity was group- and species-specific, which highlights the need for manifold management strategies (e.g., increasing or reinstating the extent of ground vegetation cover) to fulfill different species' requirements and to conserve insectivorous bats in urban green spaces.

i-Tree and urban FIA—what's the connection?

Treesearch

David J. Nowak

2015-01-01

The i-Tree program (www.itreetools.org) was developed to assess ecosystem services and values from trees and forests based on measured forest data. The i-Tree program is currently being integrated with FIA data to assess various ecosystem services and values from urban FIA data. This presentation will overview the history and use of i-Tree; the various tools of i-Tree...

Urban tree mortality: a primer on demographic approaches

Treesearch

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

2016-01-01

Realizing the benefits of tree planting programs depends on tree survival. Projections of urban forest ecosystem services and cost-benefit analyses are sensitive to assumptions about tree mortality rates. Long-term mortality data are needed to improve the accuracy of these models and optimize the public investment in tree planting. With more accurate population...

Foliar residue dynamics of azadirachtins following direct stem injection into white and green ash trees for control of emerald ash borer.

PubMed

Grimalt, Susana; Thompson, Dean; Chartrand, Derek; McFarlane, John; Helson, Blair; Lyons, Barry; Meating, Joe; Scarr, Taylor

2011-10-01

Azadirachtins are natural insecticides derived from the neem tree. The emerald ash borer (EAB) is an exotic invasive insect pest that infests various ash tree species and has the potential for significant economic, aesthetic and ecological impacts throughout North America. The initial translocation and foliar residue dynamics of azadirachtins were examined following direct injection into white and green ash trees growing in urban scenarios as a potential control for EAB. Substantial concentrations of azadirachtins A and B [mean maxima > 0.98 mg kg(-1) fresh weight (f.w.)] were observed within 2 days of injecting a specifically designed formulation of azadirachtins. Foliar residues declined exponentially through time, with half-life estimates ranging from 5.1 to 12.3 days. At the time of leaf senescence, foliar residue levels approximated 0.01 mg kg(-1) f.w., strongly mitigating the potential effects of non-target biota in soil or aquatic compartments. The magnitude and duration of exposures observed in this field study were considered to be above the thresholds required for biological effectiveness against both larval and adult life stages of EAB. Results support the use of azadirachtins as an environmentally acceptable systemic insecticide for control of EAB and protection of high-value ash trees in urban environments. Copyright © 2011 Society of Chemical Industry.

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

Treesearch

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...

Dendrometer studies in urban and rural environments in Stockholm, Sweden

NASA Astrophysics Data System (ADS)

Rocha, Eva; Holzkämper, Steffen

2017-04-01

With this study we investigate growth performances of Pinus sylvestris growing under the influence of the Urban Heat Island of the city of Stockholm, Sweden, and trees growing in the rural surrounding of the city. The aims of this investigation are to see whether and how much the growth performances differ, and which climatic parameters control the tree growth at the respective locations. Stockholm holds one of the world's longest observational climate records, reaching back to AD 1756. Since climate data are collected at a location which today is well within the Urban Heat Island, it is relevant to quantify the correlation differences between climate and tree growth data from trees which actually grow under the same climate conditions and trees growing under natural, rural climate conditions. Applied methods include Remote Sensing and GIS for identification and characterization of the Urban Heat Island, monitoring of tree growth at 30 min-resolution with point dendrometers (Ecomatik) and monitoring of local climate directly at the tree sites. First results indicate emphasized growth differences between the urban and the rural sites, with distinctively higher daily diameter change amplitudes at the urban sites compared to the rural sites, which can be explained by differences in relative humidity and temperature ranges between the sites. We will present and discuss results from 1 year of measurements, focusing on correlation analysis between climate and tree growth data from urban and rural sites, as well as practical issues with dendrometer measurements.

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

PubMed Central

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

Influence of environmental pollution on leaf properties of urban plane trees, Platanus orientalis L.

PubMed

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

2010-09-01

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.

Risk to ash from emerald ash borer: can biological control prevent the loss of ash stands?

Treesearch

Jian J. Duan; Roy G. Van Driesche; Leah S. Bauer; Daniel M. Kashian; Daniel A. Herms

2015-01-01

Ash trees (Fraxinus spp.) are an important components of both natural forests and urban plantings in the United States and Canada (Federal Register, 2003; Nowak et al., 2003). There are approximately 16 species of Fraxinus native to North America (Harlow et al., 1996; USGS, 2014), each adapted to different ecological niches across...

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

NASA Technical Reports Server (NTRS)

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.

The significance of urban trees and forests: toward a deeper understanding of values

Treesearch

John F. Dwyer; Herbert W. Schroeder; Paul H. Gobster

1991-01-01

Many city dwellers hold very strong personal ties to urban trees and forests, with some attachments approaching a spiritual involvement. Ties between people and trees are associated with traditions, symbolism, and the need to "get involved" at the local level to sustain or enhance the environment for present and future generations. Urban forestry programs...

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

Treesearch

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...

Rapid Assessment of Tree Debris Following Urban Forest Ice Storms

Treesearch

Richard J. Hauer; Angela J. Hauer; Dudley R. Hartel; Jill R. Johnson

2011-01-01

This paper presents a rapid assessment method to estimate urban tree debris following an ice storm. Data were collected from 60 communities to quantify tree debris volumes, mostly from public rights-of-way, following ice storms based on community infrastructure, weather parameters, and urban forest structure. Ice thickness, area of a community, and street distance are...

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

Treesearch

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...

AN EXAMINATION OF CITIZEN PARTICIPATION AND PROCEDURAL FAIRNESS IN LARGE-SCALE URBAN TREE PLANTING INITIATIVES IN THE UNITED STATES

EPA Science Inventory

This project will result in a typology of the degrees and forms of citizen participation in large-scale urban tree planting initiatives. It also will identify specific aspects of urban tree planting processes that residents perceive as fair and unfair, which will provide ad...

The hustle and bustle of city life: monitoring the effects of urbanisation in the African lesser bushbaby.

PubMed

Scheun, Juan; Bennett, Nigel C; Ganswindt, Andre; Nowack, Julia

2015-10-01

Urbanisation has become a severe threat to pristine natural areas, causing habitat loss and affecting indigenous animals. Species occurring within an urban fragmented landscape must cope with changes in vegetation type as well as high degrees of anthropogenic disturbance, both of which are possible key mechanisms contributing to behavioural changes and perceived stressors. We attempted to elucidate the effects of urbanisation on the African lesser bushbaby, Galago moholi, by (1) recording activity budgets and body condition (body mass index, BMI) of individuals of urban and rural populations and (2) further determining adrenocortical activity in both populations as a measure of stress via faecal glucocorticoid metabolite (fGCM) levels, following successful validation of an appropriate enzyme immunoassay test system (adrenocorticotropic hormone (ACTH) challenge test). We found that both sexes of the urban population had significantly higher BMIs than their rural counterparts, while urban females had significantly higher fGCM concentrations than rural females. While individuals in the urban population fed mainly on provisioned anthropogenic food sources and spent comparatively more time resting and engaging in aggressive interactions, rural individuals fed almost exclusively on tree exudates and spent more time moving between food sources. Although interactions with humans are likely to be lower in nocturnal than in diurnal species, our findings show that the impact of urbanisation on nocturnal species is still considerable, affecting a range of ecological and physiological aspects.

The hustle and bustle of city life: monitoring the effects of urbanisation in the African lesser bushbaby

NASA Astrophysics Data System (ADS)

Scheun, Juan; Bennett, Nigel C.; Ganswindt, Andre; Nowack, Julia

2015-10-01

Urbanisation has become a severe threat to pristine natural areas, causing habitat loss and affecting indigenous animals. Species occurring within an urban fragmented landscape must cope with changes in vegetation type as well as high degrees of anthropogenic disturbance, both of which are possible key mechanisms contributing to behavioural changes and perceived stressors. We attempted to elucidate the effects of urbanisation on the African lesser bushbaby, Galago moholi, by (1) recording activity budgets and body condition (body mass index, BMI) of individuals of urban and rural populations and (2) further determining adrenocortical activity in both populations as a measure of stress via faecal glucocorticoid metabolite (fGCM) levels, following successful validation of an appropriate enzyme immunoassay test system (adrenocorticotropic hormone (ACTH) challenge test). We found that both sexes of the urban population had significantly higher BMIs than their rural counterparts, while urban females had significantly higher fGCM concentrations than rural females. While individuals in the urban population fed mainly on provisioned anthropogenic food sources and spent comparatively more time resting and engaging in aggressive interactions, rural individuals fed almost exclusively on tree exudates and spent more time moving between food sources. Although interactions with humans are likely to be lower in nocturnal than in diurnal species, our findings show that the impact of urbanisation on nocturnal species is still considerable, affecting a range of ecological and physiological aspects.

Evaluations of Insecticides and Fungicides for Reducing Attack Rates of a new invasive ambrosia beetle (Euwallacea Sp., Coleoptera: Curculionidae: Scolytinae) in Infested Landscape Trees in California.

PubMed

Eatough Jones, Michele; Kabashima, John; Eskalen, Akif; Dimson, Monica; Mayorquin, Joey S; Carrillo, Joseph D; Hanlon, Christopher C; Paine, Timothy D

2017-08-01

A recently discovered ambrosia beetle with the proposed common name of polyphagous shot hole borer (Euwallacea sp., Coleoptera: Curculionidae: Scolytinae), is reported to attack >200 host tree species in southern California, including many important native and urban landscape trees. This invasive beetle, along with its associated fungi, causes branch dieback and tree mortality in a large variety of tree species including sycamore (Platanus racemosa Nutt.). Due to the severity of the impact of this Euwallacea sp., short-term management tools must include chemical control options for the arboriculture industry and private landowners to protect trees. We examined the effectiveness of insecticides, fungicides, and insecticide-fungicide combinations for controlling continued Euwallacea sp. attacks on previously infested sycamore trees which were monitored for 6 mo after treatment. Pesticide combinations were generally more effective than single pesticide treatments. The combination of a systemic insecticide (emamectin benzoate), a contact insecticide (bifenthrin), and a fungicide (metconazole) provided some level of control when applied on moderate and heavily infested trees. The biological fungicide Bacillus subtilis provided short-term control. There was no difference in the performance of the three triazole fungicides (propiconazole, tebuconazole, and metconazole) included in this study. Although no pesticide combination provided substantial control over time, pesticide treatments may be more effective when trees are treated during early stages of attack by this ambrosia beetle. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

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

USGS Publications Warehouse

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.

Survival, reproduction, and recruitment of woody plants after 14 years on a reforested landfill

NASA Astrophysics Data System (ADS)

Robinson, George R.; Handel, Steven N.; Schmalhofer, Victoria R.

1992-03-01

With the advent of modern sanitary landfill closure techniques, the opportunity exists for transforming municipal landfills into urban woodlands. While costs of fullscale reforestation are generally prohibitive, a modest planting of clusters of trees and shrubs could initiate or accelerate population expansions and natural plant succession from open field to diverse forest. However, among woody species that have been screened for use on landfills, these ecological potentials have not yet been investigated. We examined a 14-yr-old landfill plantation in New Jersey, USA, established to test tolerance of 19 species of trees and shrubs to landfill environments. We measured survivorship, reproduction, and recruitment within and around the experimental installation. Half of the original 190 plants were present, although survival and growth rates varied widely among species. An additional 752 trees and shrubs had colonized the plantation and its perimeter, as well as 2955 stems of vines. However, the great majority (>95%) of woody plants that had colonized were not progeny of the planted cohort, but instead belonged to 18 invading species, mostly native, bird-dispersed, and associated with intermediate stages of secondary plant succession. Based on this evidence, we recommend that several ecological criteria be applied to choices of woody species for the restoration of municipal landfills and similar degraded sites, in order to maximize rapid and economical establishment of diverse, productive woodlands.

Carbon dioxide fluxes dynamics comparison in Moscow urban forest and adjacent urban areas

NASA Astrophysics Data System (ADS)

Yaroslavtsev, Alexis; Meshalkina, Joulia; Mazirov, Ilya; Vasenev, Ivan

2017-04-01

In the beginning of the 2014 in northern district of Moscow was installed eddy covariance tower on the edge of Timiryazevskiy urban forest and Timiryazevskiy district of Moscow. Tower 34m high was constructed inside the territory of LOD (Lesnaya Opytnaya Dacha) experimental station in the south-eastern part of the forest. Main tree species of urban forest and neighboring urban areas are Acer Plantanoides, Tilia cordata, Betula pendula, Quercus robur, Pinus sylvestris. Forest itself is mixed with some small plots dominated only by deciduous or coniferous species, whether trees in urban areas was mainly deciduous. Mean canopy height is about 30m. in both forest and urban areas. The soil cover of the studied sections is represented by sod-podzolic soils with different degree of development of the humus horizon. All soils have well-developed profile of sod-podzolic soil with low power litter (only in forest area) and developed humus-accumulative horizon with high humus content (3,24%) Carbon dioxide daily fluxes from investigated area was calculated for six months of 2014 (from April till October) utilizing eddy covariance method. Most (90%) of fluxes footprints was no longer than 500m for all wind directions during the time of monitoring. Forest in 500m radius around tower is a zone of active recreation with several roads and wide path network. On the other hand closest to tower urban area characterized by a low-rise buildings (in most cases no more than 5 floors) which are mainly administration ones and have wide green areas around them very few roads and low traffic. As a result difference in calculated fluxes was not so dramatic, as it was expected. Diurnal carbon dioxide fluxes dynamics was pretty the same for all months except August, due to long period without precipitation and higher soil moisture under the forest canopy. Estimated daily fluxes values was higher in forest areas for the whole period of investigation, except August, and ranged from -2 to 8 g C CO2 d-1 m-2 with mean about 2,5 g C CO2 d-1 m-2 .

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

Treesearch

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,...

Urbanization is a main driver for the larval ecology of Aedes mosquitoes in arbovirus-endemic settings in south-eastern Côte d'Ivoire.

PubMed

Zahouli, Julien B Z; Koudou, Benjamin G; Müller, Pie; Malone, David; Tano, Yao; Utzinger, Jürg

2017-07-01

Failure in detecting naturally occurring breeding sites of Aedes mosquitoes can bias the conclusions drawn from field studies, and hence, negatively affect intervention outcomes. We characterized the habitats of immature Aedes mosquitoes and explored species dynamics along a rural-to-urban gradient in a West Africa setting where yellow fever and dengue co-exist. Between January 2013 and October 2014, we collected immature Aedes mosquitoes in water containers in rural, suburban, and urban areas of south-eastern Côte d'Ivoire, using standardized sampling procedures. Immature mosquitoes were reared in the laboratory and adult specimens identified at species level. We collected 6,159, 14,347, and 22,974 Aedes mosquitoes belonging to 17, 8, and 3 different species in rural, suburban, and urban environments, respectively. Ae. aegypti was the predominant species throughout, with a particularly high abundance in urban areas (99.374%). Eleven Aedes larval species not previously sampled in similar settings of Côte d'Ivoire were identified: Ae. albopictus, Ae. angustus, Ae. apicoargenteus, Ae. argenteopunctatus, Ae. haworthi, Ae. lilii, Ae. longipalpis, Ae. opok, Ae. palpalis, Ae. stokesi, and Ae. unilineatus. Aedes breeding site positivity was associated with study area, container type, shade, detritus, water turbidity, geographic location, season, and the presence of predators. We found proportionally more positive breeding sites in urban (2,136/3,374, 63.3%), compared to suburban (1,428/3,069, 46.5%) and rural areas (738/2,423, 30.5%). In the urban setting, the predominant breeding sites were industrial containers (e.g., tires and discarded containers). In suburban areas, containers made of traditional materials (e.g., clay pots) were most frequently encountered. In rural areas, natural containers (e.g., tree holes and bamboos) were common and represented 22.1% (163/738) of all Aedes-positive containers, hosting 18.7% of the Aedes fauna. The predatory mosquito species Culex tigripes was commonly sampled, while Toxorhynchites and Eretmapodites were mostly collected in rural areas. In Côte d'Ivoire, urbanization is associated with high abundance of Aedes larvae and a predominance of artificial containers as breeding sites, mostly colonized by Ae. aegypti in urban areas. Natural containers are still common in rural areas harboring several Aedes species and, therefore, limiting the impact of systematic removal of discarded containers on the control of arbovirus diseases.

A scaleable methodology for assessing the impacts of urban shade on the summer electricity use of residential homes

NASA Astrophysics Data System (ADS)

Taylor, Robert Vanderlei

Our cities are experiencing unprecedented growth while net global temperatures continue to trend warmer making sustainable urban development and energy conservation pressing public issues. This research explores how urban landscaping -- in particular trees and buildings -- affect summer electricity use in residential homes. I studied the interactions of urban shade and temperature to explore how vegetation distribution and intensity could play a meaningful role in heat mitigation in urban environments. Only a few studies have reconciled modeled electricity savings from tree shade with actual electricity consumption data. This research proposes a methodology for modeling the isolated effects of urban shade (tree shade vs building shade) on buildings' summertime electricity consumption from micro to mesoscales, empirically validating the modeled shade with actual electricity billing data, and comparing the electric energetic impact of tree shade effects with building shade effects. This proposed methodology seeks to resolve three primary research questions: 1) What are the modeled quantities of urban shade associated with the area of interest (AOI)? 2) To what extent do the effects of shading from trees and buildings mitigate summertime heat in the AOI? 2) To what extent do the shade effects from trees and buildings reduce summertime electricity consumption in the AOI?

Stewardship matters: Case studies in establishment success of urban trees

Treesearch

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...

City of Minneapolis, Minnesota Municipal Tree Resource Analysis

Treesearch

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

2005-01-01

Minneapolis, a vibrant city, renowned for its lakes, its livability, and its cultural wealth, 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. Trees improve urban life, making...

Seasonal variation of bacterial endophytes in urban trees

PubMed Central

Shen, Shu Yi; Fulthorpe, Roberta

2015-01-01

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 studies on endophytic populations of urban trees should expect to find significant seasonal and species-specific community differences and sampling should proceed accordingly. PMID:26042095

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

NASA Astrophysics Data System (ADS)

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.

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

Treesearch

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...

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

Treesearch

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...

Urban tree and woody yard residues : another wood resource

Treesearch

David B. McKeever; Kenneth E. Skog

2003-01-01

Urban tree and woody yard residues are an important component of the municipal solid waste (MSW) stream in the United States. In 2000, approximately 14.5 million tons of urban tree and woody yard residues was generated, nearly 7% of total MSW. Some woody residues are being recovered for recycling, composting, or other uses, but a large proportion is simply discarded....

Air quality effects of urban trees and parks

Treesearch

David Nowak; Gordon Heisler

2010-01-01

Parks are significant parts of the urban landscape and comprise about 6% of city and town areas in the conterminous United States. These urban parks are estimated to contain about 370 million trees with a structural value of approximately $300 billion. The number of park trees varies by region of the country, but they can produce significant air quality effects in and...

Urban forest assessment in northern Delaware

Treesearch

David J. Nowak; Robert E. Hoehn; Jun Wang; Andy Lee; Vikram Krishnamurthy; Gary Schwetz

2009-01-01

Presents results of an analysis of the urban forest of the Wilmington, Delaware, the metropolitan corridor in New Castle County (NCC), and Rattlesnake Run sewershed in the city of Wilmington using the Urban Forest Effects (UFORE) model. This analysis reveals that there are about 882,700 trees (19.3 percent tree cover) in the NCC metro corridor and about 136,000 trees (...

Remote sensing-based predictors improve distribution models of rare, early successional and broadleaf tree species in Utah

USGS Publications Warehouse

Zimmermann, N.E.; Edwards, T.C.; Moisen, Gretchen G.; Frescino, T.S.; Blackard, J.A.

2007-01-01

1. Compared to bioclimatic variables, remote sensing predictors are rarely used for predictive species modelling. When used, the predictors represent typically habitat classifications or filters rather than gradual spectral, surface or biophysical properties. Consequently, the full potential of remotely sensed predictors for modelling the spatial distribution of species remains unexplored. Here we analysed the partial contributions of remotely sensed and climatic predictor sets to explain and predict the distribution of 19 tree species in Utah. We also tested how these partial contributions were related to characteristics such as successional types or species traits. 2. We developed two spatial predictor sets of remotely sensed and topo-climatic variables to explain the distribution of tree species. We used variation partitioning techniques applied to generalized linear models to explore the combined and partial predictive powers of the two predictor sets. Non-parametric tests were used to explore the relationships between the partial model contributions of both predictor sets and species characteristics. 3. More than 60% of the variation explained by the models represented contributions by one of the two partial predictor sets alone, with topo-climatic variables outperforming the remotely sensed predictors. However, the partial models derived from only remotely sensed predictors still provided high model accuracies, indicating a significant correlation between climate and remote sensing variables. The overall accuracy of the models was high, but small sample sizes had a strong effect on cross-validated accuracies for rare species. 4. Models of early successional and broadleaf species benefited significantly more from adding remotely sensed predictors than did late seral and needleleaf species. The core-satellite species types differed significantly with respect to overall model accuracies. Models of satellite and urban species, both with low prevalence, benefited more from use of remotely sensed predictors than did the more frequent core species. 5. Synthesis and applications. If carefully prepared, remotely sensed variables are useful additional predictors for the spatial distribution of trees. Major improvements resulted for deciduous, early successional, satellite and rare species. The ability to improve model accuracy for species having markedly different life history strategies is a crucial step for assessing effects of global change. ?? 2007 The Authors.

Remote sensing-based predictors improve distribution models of rare, early successional and broadleaf tree species in Utah

PubMed Central

ZIMMERMANN, N E; EDWARDS, T C; MOISEN, G G; FRESCINO, T S; BLACKARD, J A

2007-01-01

Compared to bioclimatic variables, remote sensing predictors are rarely used for predictive species modelling. When used, the predictors represent typically habitat classifications or filters rather than gradual spectral, surface or biophysical properties. Consequently, the full potential of remotely sensed predictors for modelling the spatial distribution of species remains unexplored. Here we analysed the partial contributions of remotely sensed and climatic predictor sets to explain and predict the distribution of 19 tree species in Utah. We also tested how these partial contributions were related to characteristics such as successional types or species traits. We developed two spatial predictor sets of remotely sensed and topo-climatic variables to explain the distribution of tree species. We used variation partitioning techniques applied to generalized linear models to explore the combined and partial predictive powers of the two predictor sets. Non-parametric tests were used to explore the relationships between the partial model contributions of both predictor sets and species characteristics. More than 60% of the variation explained by the models represented contributions by one of the two partial predictor sets alone, with topo-climatic variables outperforming the remotely sensed predictors. However, the partial models derived from only remotely sensed predictors still provided high model accuracies, indicating a significant correlation between climate and remote sensing variables. The overall accuracy of the models was high, but small sample sizes had a strong effect on cross-validated accuracies for rare species. Models of early successional and broadleaf species benefited significantly more from adding remotely sensed predictors than did late seral and needleleaf species. The core-satellite species types differed significantly with respect to overall model accuracies. Models of satellite and urban species, both with low prevalence, benefited more from use of remotely sensed predictors than did the more frequent core species. Synthesis and applications. If carefully prepared, remotely sensed variables are useful additional predictors for the spatial distribution of trees. Major improvements resulted for deciduous, early successional, satellite and rare species. The ability to improve model accuracy for species having markedly different life history strategies is a crucial step for assessing effects of global change. PMID:18642470

Local and Landscape Drivers of Parasitoid Abundance, Richness, and Composition in Urban Gardens.

PubMed

Burks, Julia M; Philpott, Stacy M

2017-04-01

Urbanization negatively affects biodiversity, yet some urban habitat features can support diversity. Parasitoid wasps, an abundant and highly diverse group of arthropods, can inhabit urban areas and do well in areas with higher host abundance, floral resources, or local or landscape complexity. Parasitoids provide biological control services in many agricultural habitats, yet few studies have examined diversity and abundance of parasitoids in urban agroecosystems to understand how to promote conservation and function. We examined the local habitat and landscape drivers of parasitoid abundance, superfamily and family richness, and parasitoid composition in urban gardens in the California central coast. Local factors included garden size, ground cover type, herbaceous plant species, and number of trees and shrubs. Landscape characteristics included land cover and landscape diversity around gardens. We found that garden size, mulch cover, and urban cover within 500 m of gardens predicted increases in parasitoid abundance within gardens. The height of herbaceous vegetation and tree and shrub richness predicted increases in superfamily and family richness whereas increases in urban cover resulted in declines in parasitoid richness. Abundance of individual superfamilies and families responded to a wide array of local and landscape factors, sometimes in opposite ways. Composition of parasitoid communities responded to changes in garden size, herbaceous plant cover, and number of flowers. Thus, both local scale management and landscape planning may impact the abundance, diversity, and community composition of parasitoids in urban gardens, and may result in differences in the effectiveness of parasitoids in biological control. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

[Application of biotope mapping model integrated with vegetation cover continuity attributes in urban biodiversity conservation].

PubMed

Gao, Tian; Qiu, Ling; Chen, Cun-gen

2010-09-01

Based on the biotope classification system with vegetation structure as the framework, a modified biotope mapping model integrated with vegetation cover continuity attributes was developed, and applied to the study of the greenbelts in Helsingborg in southern Sweden. An evaluation of the vegetation cover continuity in the greenbelts was carried out by the comparisons of the vascular plant species richness in long- and short-continuity forests, based on the identification of woodland continuity by using ancient woodland indicator species (AWIS). In the test greenbelts, long-continuity woodlands had more AWIS. Among the forests where the dominant trees were more than 30-year-old, the long-continuity ones had a higher biodiversity of vascular plants, compared with the short-continuity ones with the similar vegetation structure. The modified biotope mapping model integrated with the continuity features of vegetation cover could be an important tool in investigating urban biodiversity, and provide corresponding strategies for future urban biodiversity conservation.

Positive effects of afforestation efforts on the health of urban soils

Treesearch

Emily E. Oldfield; Alexander J. Felson; Stephen A. Wood; Richard A. Hallett; Michael S. Strickland; Mark A. Bradford

2014-01-01

Large-scale tree planting projects in cities are increasingly implemented as a strategy to improve the urban environment. Trees provide multiple benefits in cities, including reduction of urban temperatures, improved air quality, mitigation of storm-water run-off, and provision of wildlife habitat. How urban afforestation affects the properties and functions of urban...

City of Berkeley, California Municipal Tree Resource Analysis

Treesearch

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...

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

Treesearch

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...

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

Treesearch

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...

Sudden Oak Death, Phytophthora ramorum: A Persistent Threat to Oaks and Other Tree Species

Treesearch

S.J. Frankel; K.M. Palmieri

2014-01-01

This paper reviews the status and management of sudden oak death and “sudden larch death” in the urban and wildland forests of California, Oregon, and the UK. The causal pathogen, Phytophthora ramorum, was discovered in all three locations over a decade ago; however, efforts to contain and eliminate infestations have been unsuccessful. These less...

ISPM No. 15 and the incidence of wood pests: Recent findings, policy changes, and current knowledge gaps

Treesearch

Robert A. Haack; Eckehard G. Brockerhoff

2011-01-01

Largely as a result of international trade, hundreds of species of bark- and wood-infesting insects have become established in countries outside their native range. Many of these exotic insects have caused severe economic and environmental impact to urban and forest trees in the receiving countries. Most bark- and wood-infesting insects have been transported to new...

Nitrogen and sulfur desposition and forest nutrient status in the valley of Mexico

Treesearch

Mark E. Fenn; L.I. De Baur; A. Quevedo-Nolasco; C. Rodriguez-Frausto

1999-01-01

Mexico City experiences some of the most severe air pollution in the world. Ozone injury has been documented in sensitive tree species in urban and forested areas in the Valley of Mexico. However, little is known of the levels of other atmospheric pollutants and their ecological effects on forests in the Valley of Mexico. In this study bulk throughfall deposition of...

Comparative morphometric and chemical analyses of phenotypes of two invasive ambrosia beetles (Euwallacea spp.) in the United States

Treesearch

Yigen Chen; Paul L. Dallara; Lori J. Nelson; Tom W. Coleman; Stacy M. Hishinuma; Daniel Carrillo; Steven J. Seybold

2016-01-01

The polyphagous shot hole borer (PSHB), Euwallacea sp., was first detected in 2003 in Los Angeles County, California, USA. Recently, this invasive species has become a major pest of many hardwood trees in urban and wildland forests throughout southern California. PSHB is nearly identical in morphology and life history to the tea shot hole borer (...

Nitrogen and sulfur deposition and forest nutrient status in the Valley of Mexico

Treesearch

M. E. Fenn; L. I. de Bauer; A. Quevedo-Nolasco; Rodriquez-Frausto-C.

1999-01-01

Mexico City experiences some of the most severe air pollution in the world. Ozone injury has been documented in sensitive tree species in urban and forested areas in the Valley of Mexico. However, little is known of the levels of other atmospheric pollutants and their ecological effects on forests in the Valley of Mexico. In this study bulk throughfall deposition of...

Impacts of Trees on Urban Environment in the Contiguous United States

NASA Astrophysics Data System (ADS)

Wang, C.; Upreti, R.; Wang, Z.; Yang, J.

2017-12-01

Mounting empirical evidence shows that urban trees are effective in mitigating the thermal stress in the built environment, whereas large scale numerical simulations remain scarce. In this study, we evaluated the effects of shade trees on the built environment in terms of radiative cooling, pedestrian thermal comfort, and surface energy balance, carried out over the contiguous United States (CONUS). A coupled Weather Research and Forecasting-urban modeling system was adopted, incorporating exclusively the radiative shading effect of urban trees. Results show that on average the mean 2-m air temperature in urban areas decreases by 3.06 ˚C, and the 2-m relative humidity increases by 13.62% over the entire CONUS with the shading effect. Analysis of pedestrian thermal comfort shows that shade trees help to improve summer thermal comfort level, but could be detrimental in the winter for Northern cities. In addition, it was found that trees alter the surface energy balance by primarily enhancing the radiative cooling, leading to significant re-distribution of the sensible heat while leaving the ground heat storage comparatively intact.

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

Treesearch

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...

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

PubMed

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 in high resolution remote sensing have the potential to improve the characterization and management of urban vegetation. Copyright © 2014 Elsevier B.V. All rights reserved.

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

Treesearch

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...

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

Treesearch

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).

Urban greening impacts on tropospheric ozone

NASA Astrophysics Data System (ADS)

Grote, R.; Churkina, G.; Butler, T. M.; Morfopoulos, C.

2013-12-01

Cities are characterized by elevated air temperatures as well as high anthropogenic emissions of air pollutants. Cities' greening in form of urban parks, street trees, and vegetation on roofs and walls of buildings is supposed to generally mitigate negative impacts on human health and well-being. However, high emissions of biogenic volatile organic compounds (BVOC) from certain popular urban plants in combination with the elevated concentrations of NOx have the potential to increase ground-level ozone concentrations - with negative impacts on health, agriculture, and climate. Policies targeting reduction of ground-level ozone in urban and suburban areas therefore must consider limiting BVOC emissions along with measures for decreasing NOx and VOC from anthropogenic sources. For this, integrated climate/ chemistry models are needed that take into account the species-specific physiological responses of urban plants which in turn drive their emission behavior. Current models of urban climate and air quality 1) do not account for the feedback between ozone concentrations, productivity, and BVOC emission and 2) do not distinguish different physiological properties of urban tree species. Instead environmental factors such as light, temperature, carbon dioxide, and water supply are applied disregarding interactions between such influences. Thus we may not yet be able to represent the impacts of air pollution under multiple changed conditions such as climate change, altered anthropogenic emission patterns, and new urban structures. We present here the implementation of the new BVOC emission model (Morfopolous et al., in press) that derives BVOC emissions directly from the electron production potential and consumption from photosynthesis calculation that is already supplied by the CLM land surface model. The new approach has the advantage that many environmental drivers of BVOC emissions are implicitly considered in the description of plant photosynthesis and phenology. We investigate the tradeoff between vegetation driven ozone -reduction and -formation processes in dependence on temperature, radiation, CO2 and O3 concentrations. We have parameterized suitable plant functional types for different urban greening structures, currently focusing on central European vegetation. The modified CLM model is applied in a global (CESM) and a regional climate/ air quality model (WRF-Chem) to calculate realistic ozone concentrations in the influence zones of urban conglomerations. BVOC emissions and their impacts are also calculated with the standard MEGAN2.1 approach for comparison. The simulation results are analyzed and discussed in view of the models suitability for air quality scenario estimates under simultaneously changing climate, anthropogenic emissions and plant species composition. References Morfopoulos, C., Prentice, I.C., Keenan T.F., Friedlingstein, P., Medlyn, B., Penuelas, J., Possel, M. (in press): A unifying conceptual model for the environmental responses of isoprene emission by plants. Annals of Botany

Oxidative stress in birds along a NOx and urbanisation gradient: An interspecific approach.

PubMed

Salmón, Pablo; Stroh, Emilie; Herrera-Dueñas, Amparo; von Post, Maria; Isaksson, Caroline

2018-05-01

Urbanisation is regarded as one of the most threatening global issues for wildlife, however, measuring its impact is not always straight forward. Oxidative stress physiology has been suggested to be a useful biomarker of health and therefore, a potentially important indicator of the impact that urban environmental stressors, especially air pollution, can have on wildlife. For example, nitrogen oxides (NO x ), released during incomplete combustion of fossil fuels, are highly potent pro-oxidants, thus predicted to affect either the protective antioxidants and/or cause oxidative damage to bio-molecules. To date, epidemiological modelling of the predicted association between oxidative stress and NO x exposure has not been performed in wild animals. Here, we address this short-coming, by investigating multiple oxidative stress markers in four common passerine bird species, the blue tit (Cyanistes caeruleus), great tit (Parus major), house sparrow (Passer domesticus) and tree sparrow (Passer montanus), living along a gradient of NO x and urbanisation levels in southern Sweden. First of all, the results revealed that long- and medium-term (one month and one week, respectively) NO x levels were highly correlated with the level of urbanisation. This confirms that the commonly used urbanisation index is a reliable proxy for urban air pollution. Furthermore, in accordance to our prediction, individuals exposed to higher long- and medium-term NO x levels/urbanisation had higher plasma antioxidant capacity. However, only tree sparrows showed higher oxidative damage (protein carbonyls) in relation to NO x levels and this association was absent with urbanisation. Lipid peroxidation, glutathione and superoxide dismutase levels did not co-vary with NO x /urbanisation. Given that most oxidative stress biomarkers showed strong species-specificity, independent of variation in NO x /urbanisation, the present study highlights the need to study variation in oxidative stress across contexts, seasons and life-stages in order to understand how the ecology and phylogeny of species interact to affect species resilience to urban environmental stress. Copyright © 2017 Elsevier B.V. All rights reserved.

Urban forests

Treesearch

David J. Nowak; Eric J. Greenfield

2016-01-01

Trees and forests are resources that significantly affect the health and well-being of people who live in urban areas where more than 80 percent of the U.S. population resides. These trees within our cities and communities provide many ecosystem services and values to both urban and rural populations. Healthy urban and rural forests are critical for sustaining quality...

Gainesville's urban forest canopy cover

Treesearch

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...

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

Treesearch

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:...

Urban Tree Risk Management:A Community Guide to Program Design and Implementation

Treesearch

Jill Pokorny; Joseph O' Brien; Richard Hauer; Gary Johnson; Jana Albers; Peter Bedker; Manfred Mielke

2003-01-01

Urban Tree Risk Management: A Community Guide to Program Design and Implementation is a fully illustrated, easy to read training manual written for community leaders, administrators, city foresters, parks and public works staff, and private tree care practitioners. The manual is designed to assist communities design, adopt and implement tree risk management programs,...

Decreased losses of woody plant foliage to insects in large urban areas are explained by bird predation.

PubMed

Kozlov, Mikhail V; Lanta, Vojtěch; Zverev, Vitali; Rainio, Kalle; Kunavin, Mikhail A; Zvereva, Elena L

2017-10-01

Despite the increasing rate of urbanization, the consequences of this process on biotic interactions remain insufficiently studied. Our aims were to identify the general pattern of urbanization impact on background insect herbivory, to explore variations in this impact related to characteristics of both urban areas and insect-plant systems, and to uncover the factors governing urbanization impacts on insect herbivory. We compared the foliar damage inflicted on the most common trees by defoliating, leafmining and gall-forming insects in rural and urban habitats associated with 16 European cities. In two of these cities, we explored quality of birch foliage for herbivorous insects, mortality of leafmining insects due to predators and parasitoids and bird predation on artificial plasticine larvae. On average, the foliage losses to insects were 16.5% lower in urban than in rural habitats. The magnitude of the overall adverse effect of urbanization on herbivory was independent of the latitude of the locality and was similar in all 11 studied tree species, but increased with an increase in the size of the urban area: it was significant in large cities (city population 1-5 million) but not significant in medium-sized and small towns. Quality of birch foliage for herbivorous insects was slightly higher in urban habitats than in rural habitats. At the same time, leafminer mortality due to ants and birds and the bird attack intensity on dummy larvae were higher in large cities than in rural habitats, which at least partially explained the decline in insect herbivory observed in response to urbanization. Our findings underscore the importance of top-down forces in mediating impacts of urbanization on plant-feeding insects: factors favouring predators may override the positive effects of temperature elevation on insects and thus reduce plant damage. © 2017 John Wiley & Sons Ltd.

Tree and impervious cover change in U.S

Treesearch

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...

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

NASA Astrophysics Data System (ADS)

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.

Urban heat island effect on cicada densities in metropolitan Seoul.

PubMed

Nguyen, Hoa Q; Andersen, Desiree K; Kim, Yuseob; Jang, Yikweon

2018-01-01

Urban heat island (UHI) effect, the ubiquitous consequence of urbanization, is considered to play a major role in population expansion of numerous insects. Cryptotympana atrata and Hyalessa fuscata are the most abundant cicada species in the Korean Peninsula, where their population densities are higher in urban than in rural areas. We predicted a positive relationship between the UHI intensities and population densities of these two cicada species in metropolitan Seoul. To test this prediction, enumeration surveys of cicada exuviae densities were conducted in 36 localities located within and in the vicinity of metropolitan Seoul. Samples were collected in two consecutive periods from July to August 2015. The abundance of each species was estimated by two resource-weighted densities, one based on the total geographic area, and the other on the total number of trees. Multiple linear regression analyses were performed to identify factors critical for the prevalence of cicada species in the urban habitat. C. atrata and H. fuscata were major constituents of cicada species composition collected across all localities. Minimum temperature and sampling period were significant factors contributing to the variation in densities of both species, whereas other environmental factors related to urbanization were not significant. More cicada exuviae were collected in the second rather than in the first samplings, which matched the phenological pattern of cicadas in metropolitan Seoul. Cicada population densities increased measurably with the increase in temperature. Age of residential complex also exhibited a significantly positive correlation to H. fuscata densities, but not to C. atrata densities. Effects of temperature on cicada densities have been discerned from other environmental factors, as cicada densities increased measurably in tandem with elevated temperature. Several mechanisms may contribute to the abundance of cicadas in urban environments, such as higher fecundity of females, lower mortality rate of instars, decline in host plant quality, and local adaptation of organisms, but none of them were tested in the current study. In sum, results of the enumeration surveys of cicada exuviae support the hypothesis that the UHI effect underlies the population expansion of cicadas in metropolitan Seoul. Nevertheless, the underlying mechanisms for this remain untested.

Chicago's urban forest ecosystem: results of the Chicago Urban Forest Climate Project

Treesearch

Gregory E. McPherson; David J. Nowak; Rowan A. Rowntree

1994-01-01

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...

The relationship between tree canopy and crime rates across an urban-rural gradient in the greater Baltimore region

Treesearch

Austin Troy; J. Morgan Grove; Jarlath O' Neill-Dunne

2012-01-01

The extent to which urban tree cover influences crime is in debate in the literature. This research took advantage of geocoded crime point data and high resolution tree canopy data to address this question in Baltimore City and County, MD, an area that includes a significant urban-rural gradient. Using ordinary least squares and spatially adjusted regression and...

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

PubMed

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.

Voxel-Based Approach for Estimating Urban Tree Volume from Terrestrial Laser Scanning Data

NASA Astrophysics Data System (ADS)

Vonderach, C.; Voegtle, T.; Adler, P.

2012-07-01

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 extracted branch areas Ai of this horizontal cross-section multiplied by the thickness of the voxel layer. A significant improvement of this method could be obtained by a reasonable determination of the threshold for excluding sparsely filled voxels for noise reduction which can be defined based on the function change of filled voxels. Field measurements were used to validate this method. For a quality assessment nine deciduous trees were selected for control and were scanned before felling and weighing. The results are in good accordance to the control trees within a range of only -5.1% to +14.3%. The determined DBH values show only minor deviations, while the heights of trees are systematically underestimated, mainly due to field measurements. Possible error sources including gaps in surface voxels, influence of thin twigs and others are discussed in detail and several improvements of this approach are suggested. The advantages of the algorithm are the robustness and simple structure as well as the quality of the results obtained. The drawbacks are the high effort both in data acquisition and analysis, even if a remarkable data reduction can be obtained by the voxel structure.

Where the woodland ends: How edges affect landscape structure and physiological responses of Quercus agrifolia

NASA Astrophysics Data System (ADS)

de Chant, Timothy Paul

Forests and woodlands are integral parts of ecosystems across the globe, but they are threatened by a variety of factors, including urbanization and introduced forest pathogens. These two forces are fundamentally altering ecosystems, both by removing forest cover and reshaping landscapes. Comprehending how these two processes have changed forest ecosystems is an important step toward understanding how the affected systems will function in the future. I investigated the range of edge effects that result from disturbance brought about by forest pathogens and urbanization in two coastal oak woodlands in Marin County, California. Oak woodlands are a dynamic part of California's landscape, reacting to changes in their biotic and abiotic environments across a range of spatial and temporal scales. Sudden Oak Death, caused by the introduced forest pathogen Phytophthora ramorum, has led to widespread mortality of many tree species in California's oak woodlands. I investigated how the remaining trees respond to such rapid changes in canopy structure (Chapter 2), and my results revealed a forest canopy quick to respond to the new openings. Urbanization, another disturbance regime, operates on a longer time scale. Immediately following urban development, forest edges are strikingly linear, but both forest processes and homeowner actions likely work in concert to disrupt the straight edge (Chapter 3). Forest edges grew more sinuous within 14 years of the initial disturbance, and continued to do so for the remainder of the study, another 21 years. Individual Quercus agrifolia trees also respond to urban edges decades after disturbance (Chapter 4), and their reaction is reflected in declining stable carbon isotope values (delta13C). This change suggests trees may have increased their stomatal conductance in response to greater water availability, reduced their photosynthetic rate as a result of stress, or some combination of both. Edges have far reaching and long lasting effects on forest structure and function. Investigations of their impacts on multiple spatial and temporal scales are important in determining the range of effects they have on forest ecosystems. Studies that combine remote sensing, geographic information systems, and field studies may help us understand the ecological consequences of forest edges.

Evidence in support of the role of disturbance vegetation for women’s health and childcare in Western Africa

PubMed Central

2014-01-01

Background In savannah-dominated Bénin, West Africa, and forest-dominated Gabon, Central Africa, plants are a major source of healthcare for women and children. Due to this high demand and the reliance on wild populations as sources for medicinal plants, overharvesting of African medicinal plants is a common concern. Few studies in Western Africa, however, have assessed variations in harvest patterns across different ecological zones and within local communities. Methods We investigated which vegetation types women accessed to harvest medicinal plants by conducting 163 questionnaires with market vendors and women from urban and rural communities. We made botanical vouchers of cited species and collected information on their vegetation type and cultivation status. Results Secondary vegetation was a crucial asset; over 80% of the 335 Beninese and 272 Gabonese plant species came from disturbance vegetation and home gardens. In Bénin, access to trade channels allowed female market vendors to use more vulnerable species than rural and urban women who harvested for personal use. In Gabon, no relationship was found between vulnerable plant use and informant type. Conclusions This study highlights the underemphasized point that secondary vegetation is an asset for women and children’s health in both savanna-dominated and forest-dominated landscapes. The use of disturbance vegetation demonstrates women’s resilience in meeting healthcare needs in the limited amount of space that is available to them. Species of conservation concern included forest species and savanna trees sold at markets in Bénin, especially Xylopia aethiopica, Khaya senegalensis, and Monodora myristica, and the timber trees with medicinal values in Gabon, such as Baillonella toxisperma. PMID:24885805

Quantifying the influences of various ecological factors on land surface temperature of urban forests.

PubMed

Ren, Yin; Deng, Lu-Ying; Zuo, Shu-Di; Song, Xiao-Dong; Liao, Yi-Lan; Xu, Cheng-Dong; Chen, Qi; Hua, Li-Zhong; Li, Zheng-Wei

2016-09-01

Identifying factors that influence the land surface temperature (LST) of urban forests can help improve simulations and predictions of spatial patterns of urban cool islands. This requires a quantitative analytical method that combines spatial statistical analysis with multi-source observational data. The purpose of this study was to reveal how human activities and ecological factors jointly influence LST in clustering regions (hot or cool spots) of urban forests. Using Xiamen City, China from 1996 to 2006 as a case study, we explored the interactions between human activities and ecological factors, as well as their influences on urban forest LST. Population density was selected as a proxy for human activity. We integrated multi-source data (forest inventory, digital elevation models (DEM), population, and remote sensing imagery) to develop a database on a unified urban scale. The driving mechanism of urban forest LST was revealed through a combination of multi-source spatial data and spatial statistical analysis of clustering regions. The results showed that the main factors contributing to urban forest LST were dominant tree species and elevation. The interactions between human activity and specific ecological factors linearly or nonlinearly increased LST in urban forests. Strong interactions between elevation and dominant species were generally observed and were prevalent in either hot or cold spots areas in different years. In conclusion, quantitative studies based on spatial statistics and GeogDetector models should be conducted in urban areas to reveal interactions between human activities, ecological factors, and LST. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

NASA Astrophysics Data System (ADS)

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 actions for addressing future impacts from climate change.

Spatiotemporal throughfall patterns beneath an urban tree row

NASA Astrophysics Data System (ADS)

Bogeholz, P.; Van Stan, J. T., II; Hildebrandt, A.; Friesen, J.; Dibble, M.; Norman, Z.

2016-12-01

Much recent research has focused on throughfall patterns in natural forests as they can influence the heterogeneity of surface ecohydrological and biogeochemical processes. However, to the knowledge of the authors, no work has assessed how urban forest structures affect the spatiotemporal variability of throughfall water flux. Urbanization greatly alters not only a significant portion of the land surface, but canopy structure, with the most typical urban forest configuration being landscaped tree rows along streets, swales, parking lot medians, etc. This study examines throughfall spatiotemporal patterns for a landscaped tree row of Pinus elliottii (Engelm., slash pine) on Georgia Southern University's campus (southeastern, USA) using 150 individual observations per storm. Throughfall correlation lengths beneath this tree row were similar to, but appeared to be more stable across storm size than, observations in past studies on natural forests. Individual tree overlap and the planting interval also may more strongly drive throughfall patterns in tree rows. Meteorological influences beyond storm magnitude (intensity, intermittency, wind conditions, and atmospheric moisture demand) are also examined.

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

Treesearch

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...

Urban Forest Health Monitoring in the United States

Treesearch

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...

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

Treesearch

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.

Identifying common practices and challenges for local urban tree monitoring programs across the United States

Treesearch

Lara A. Roman; E. Gregory McPherson; Bryant C. Scharenbroch; Julia Bartens

2013-01-01

Urban forest monitoring data are essential to assess the impacts of tree planting campaigns and management programs. Local practitioners have monitoring projects that have not been well documented in the urban forestry literature. To learn more about practitioner-driven monitoring efforts, the authors surveyed 32 local urban forestry organizations across the United...

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

Treesearch

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...

Tree canopy change and neighborhood stability: A comparative analysis of Washington, D.C. and Baltimore, MD

Treesearch

Wen-Ching Chuang; Christopher G. Boone; Dexter H. Locke; J. Morgan Grove; Ali Whitmer; Geoffrey Buckley; Sainan Zhang

2017-01-01

Trees provide important health, ecosystem, and aesthetic services in urban areas, but they are unevenly distributed. Some neighborhoods have abundant tree canopy and others nearly none. We analyzed how neighborhood characteristics and changes in income over time related to the distribution of urban tree canopy in Washington, D.C. and Baltimore, MD. We used stepwise...

Urban Watershed Forestry Manual Part 2 Conserving and Planting Trees at Development Sites

Treesearch

Karen Cappiella; Tom Schueler; Tiffany Wright

2006-01-01

This manual is the second in a three-part series on using trees to protect and restore urban watersheds. A brief description of each part follows. Part 2. Conserving and Planting Trees at Development Sites presents specific ways to enable developers, engineers, or landscape architects to incorporate more trees into a development site. The proposed approach focuses...

Impact of extensive street tree loss on urban dwellers' sense of place

Treesearch

Mary Carol. Hunter

2010-01-01

I took advantage of a natural experiment that occurred in southeast Michigan when an exotic insect pest caused the death and removal of more than 10,000 urban street trees within several years. Where dead street trees were clustered, the ecological and aesthetic integrity of neighborhoods changed dramatically, and the restorative benefits provided by these trees were...

Carbon storage and sequestration by urban trees in the USA

Treesearch

David J. Nowak; Daniel E. Crane

2002-01-01

Based on field data from 10 USA cities and national urban tree cover data, it is estimated that urban trees in the coterminous USA currently store 700 million tonnes of carbon ($14,300 million value) with a gross carbon sequestration rate of 22.8 million tC/yr ($460 rnillion/year). Carbon storage within cities ranges From 1.2 million tC in New York, NY, to 19,300 tC in...

A novel association between Rhodnius neglectus and the Livistona australis palm tree in an urban center foreshadowing the risk of Chagas disease transmission by vectorial invasions in Monte Alto City, São Paulo, Brazil.

PubMed

Carvalho, Danila B; Almeida, Carlos E; Rocha, Cláudia S; Gardim, Sueli; Mendonça, Vagner J; Ribeiro, Aline R; Alves, Zulimar C P V T; Ruellas, Kellem T; Vedoveli, Alan; da Rosa, João A

2014-02-01

After several public notifications of domiciliary invasions, palm trees were investigated in downtown Monte Alto City, São Paulo State, Brazil, in proximity to the city hall building, the main church, condominiums and marketing establishments. One hundred seventy four palm trees of 10 species were investigated, in which 72 specimens of Rhodnius neglectus, a potential Chagas disease vector, were captured via manual methods. All insects were collected from dead leaves, organic debris and bird nests in the only three Livistona australis palm trees in the central park square. This was the first record of R. neglectus colonizing this palm species. Although no Trypanosoma cruzi was found by abdominal compression followed by light microscopy, the poor nutritional status of the bugs hampered the examination of gut contents for parasite detection. Furthermore, the central crowns of the trees, which shelter bats (Chiroptera: Mammalia), could not be carefully searched for insects due to difficult access. This new finding highlights the sudden alteration in insect behavior, probably as a result of man's interference. This report aims to warn those involved in the health system about this new threat, justifying detailed research of the area to evaluate the magnitude of this emerging public health issue. Copyright © 2013 Elsevier B.V. All rights reserved.

Biomonitoring of Urban Pollution Using Silicon-Accumulating Species, Phyllostachys aureosulcata 'Aureocaulis'.

PubMed

Morina, Filis; Vidović, Marija; Srećković, Tatjana; Radović, Vesela; Veljović-Jovanović, Sonja

2017-12-01

We investigated metal accumulation in bamboo leaves during three seasons at three urban locations differing in pollution levels. The higher content of Cu, Pb, and Zn in the leaves was in correlation with the highest bioavailable content of these elements in the soil at the most polluted location. The content of leaf trace elements was higher in summer and autumn compared to spring. Scanning electron microscopy with energy dispersive X-ray spectroscopy showed that Si accumulation in bamboo leaves was the highest in epidermis and vascular tissue, and was co-localized with trace metals. Analysis of phytoliths showed co-deposition of Al, C, and Si, implying the involvement of Si in metal detoxification. Compared to a common urban tree, linden, bamboo showed better capacity to maintain cellular redox homeostasis under deteriorated environmental conditions. The results suggest that bamboo can be efficiently used for biomonitoring of air and soil metal pollution and remediation in urban areas.

Photosynthesis and isoprene emission from trees along an urban-rural gradient in Texas.

PubMed

Lahr, Eleanor C; Schade, Gunnar W; Crossett, Caitlin C; Watson, Matthew R

2015-11-01

Isoprene emission is an important mechanism for improving the thermotolerance of plant photosystems as temperatures increase. In this study, we measured photosynthesis and isoprene emission in trees along an urban-rural gradient that serves as a proxy for climate change, to understand daily and seasonal responses to changes in temperature and other environmental variables. Leaf-level gas exchange and basal isoprene emission of post oak (Quercus stellata) and sweet gum (Liquidambar styraciflua) were recorded at regular intervals over an entire growing season at urban, suburban, and rural sites in eastern Texas. In addition, the temperature and atmospheric carbon dioxide concentration experienced by leaves were experimentally manipulated in spring, early summer, and late summer. We found that trees experienced lower stomatal conductance and photosynthesis and higher isoprene emission, at the urban and suburban sites compared to the rural site. Path analysis indicated a daily positive effect of isoprene emission on photosynthesis, but unexpectedly, higher isoprene emission from urban trees was not associated with improved photosynthesis as temperatures increased during the growing season. Furthermore, urban trees experienced relatively higher isoprene emission at high CO2 concentrations, while isoprene emission was suppressed at the other sites. These results suggest that isoprene emission may be less beneficial in urban, and potentially future, environmental conditions, particularly if higher temperatures override the suppressive effects of high CO2 on isoprene emission. These are important considerations for modeling future biosphere-atmosphere interactions and for understanding tree physiological responses to climate change. © 2015 John Wiley & Sons Ltd.

Predicting summer site occupancy for an invasive species, the common brushtail possum (Trichosurus vulpecula), in an urban environment.

PubMed

Adams, Amy L; Dickinson, Katharine J M; Robertson, Bruce C; van Heezik, Yolanda

2013-01-01

Invasive species are often favoured in fragmented, highly-modified, human-dominated landscapes such as urban areas. Because successful invasive urban adapters can occupy habitat that is quite different from that in their original range, effective management programmes for invasive species in urban areas require an understanding of distribution, habitat and resource requirements at a local scale that is tailored to the fine-scale heterogeneity typical of urban landscapes. The common brushtail possum (Trichosurus vulpecula) is one of New Zealand's most destructive invasive pest species. As brushtail possums traditionally occupy forest habitat, control in New Zealand has focussed on rural and forest habitats, and forest fragments in cities. However, as successful urban adapters, possums may be occupying a wider range of habitats. Here we use site occupancy methods to determine the distribution of brushtail possums across five distinguishable urban habitat types during summer, which is when possums have the greatest impacts on breeding birds. We collected data on possum presence/absence and habitat characteristics, including possible sources of supplementary food (fruit trees, vegetable gardens, compost heaps), and the availability of forest fragments from 150 survey locations. Predictive distribution models constructed using the programme PRESENCE revealed that while occupancy rates were highest in forest fragments, possums were still present across a large proportion of residential habitat with occupancy decreasing as housing density increased and green cover decreased. The presence of supplementary food sources was important in predicting possum occupancy, which may reflect the high nutritional value of these food types. Additionally, occupancy decreased as the proportion of forest fragment decreased, indicating the importance of forest fragments in determining possum distribution. Control operations to protect native birds from possum predation in cities should include well-vegetated residential areas; these modified habitats not only support possums but provide a source for reinvasion of fragments.

The phyllophagous of woody plants of genus Ulmus in protective plantings of arid zone

NASA Astrophysics Data System (ADS)

Belitskaya, M. N.; Gribust, I. R.; Nefed'eva, E. E.; Filimonova, O. S.; Golovanova, M. A.

2018-01-01

Creating of long-lasting, normally developing plantings on the urbanized territories in the arid zones is difficult. The main tree species are elm (Fam. Ulmaceae - more than 70% of tree composition). They have a high drought and salt tolerance, rapid growth. They are widely used in the creation of artificial forest plantings in steppes and deserts. The main part of the plantations was created in the 50-60 years of 20th century. Today the aging of plants is observing. Trees of this age lose their physiological and decorative potential as well as resistance to pests under intensive anthropogenic impact. At the forest pathology research about 90 % of the plants of elm species of plantings of various types and categories were identified to be in poor condition. Leaf-eating pests play an active role in the deterioration of their sanitary state. Xanthogaleruca luteola (Müller, 1766), Cladius ulmi (Linnaeus, 1758), and Aproceros leucopoda (Takeuchi, 1939) have a special harmfulness as well as the regularity of the local centers among the mass phyllophagous of plants of the family. The last two species were discovered in artificial plantations for the first time. The destructive effect of those pests on certain types of elm plants is uneven.

Forecasting Urban Forest Ecosystem Structure, Function, and Vulnerability

NASA Astrophysics Data System (ADS)

Steenberg, James W. N.; Millward, Andrew A.; Nowak, David J.; Robinson, Pamela J.; Ellis, Alexis

2017-03-01

The benefits derived from urban forest ecosystems are garnering increasing attention in ecological research and municipal planning. However, because of their location in heterogeneous and highly-altered urban landscapes, urban forests are vulnerable and commonly suffer disproportionate and varying levels of stress and disturbance. The objective of this study is to assess and analyze the spatial and temporal changes, and potential vulnerability, of the urban forest resource in Toronto, Canada. This research was conducted using a spatially-explicit, indicator-based assessment of vulnerability and i-Tree Forecast modeling of temporal changes in forest structure and function. Nine scenarios were simulated for 45 years and model output was analyzed at the ecosystem and municipal scale. Substantial mismatches in ecological processes between spatial scales were found, which can translate into unanticipated loss of function and social inequities if not accounted for in planning and management. At the municipal scale, the effects of Asian longhorned beetle and ice storm disturbance were far less influential on structure and function than changes in management actions. The strategic goals of removing invasive species and increasing tree planting resulted in a decline in carbon storage and leaf biomass. Introducing vulnerability parameters in the modeling increased the spatial heterogeneity in structure and function while expanding the disparities of resident access to ecosystem services. There was often a variable and uncertain relationship between vulnerability and ecosystem structure and function. Vulnerability assessment and analysis can provide strategic planning initiatives with valuable insight into the processes of structural and functional change resulting from management intervention.

Forecasting Urban Forest Ecosystem Structure, Function, and Vulnerability.

PubMed

Steenberg, James W N; Millward, Andrew A; Nowak, David J; Robinson, Pamela J; Ellis, Alexis

2017-03-01

The benefits derived from urban forest ecosystems are garnering increasing attention in ecological research and municipal planning. However, because of their location in heterogeneous and highly-altered urban landscapes, urban forests are vulnerable and commonly suffer disproportionate and varying levels of stress and disturbance. The objective of this study is to assess and analyze the spatial and temporal changes, and potential vulnerability, of the urban forest resource in Toronto, Canada. This research was conducted using a spatially-explicit, indicator-based assessment of vulnerability and i-Tree Forecast modeling of temporal changes in forest structure and function. Nine scenarios were simulated for 45 years and model output was analyzed at the ecosystem and municipal scale. Substantial mismatches in ecological processes between spatial scales were found, which can translate into unanticipated loss of function and social inequities if not accounted for in planning and management. At the municipal scale, the effects of Asian longhorned beetle and ice storm disturbance were far less influential on structure and function than changes in management actions. The strategic goals of removing invasive species and increasing tree planting resulted in a decline in carbon storage and leaf biomass. Introducing vulnerability parameters in the modeling increased the spatial heterogeneity in structure and function while expanding the disparities of resident access to ecosystem services. There was often a variable and uncertain relationship between vulnerability and ecosystem structure and function. Vulnerability assessment and analysis can provide strategic planning initiatives with valuable insight into the processes of structural and functional change resulting from management intervention.

A squirrel searches for food at KSC

NASA Technical Reports Server (NTRS)

1999-01-01

An Eastern gray squirrel pauses in its daily search for food in the Merritt Island National Wildlife Refuge, which shares a boundary with Kennedy Space Center. The Eastern gray squirrel is found in wooded, suburban, and urban areas statewide. It nests in tree hollows or leaf nests in treetops. It forages during the day, mainly early morning and late afternoon, both on the ground and in trees, living on a diet of acorns, nuts, fruits, berries, insects, and bird eggs. Food plants include cypress, buckeyes, elms, grapes, tulip trees, mulberries, and tupelo. It breeds in late winter or early spring and again in late spring or summer, bearing two to six young. The eastern gray squirrel chatters when disturbed. The 92,000-acre wildlife refuge is a habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles.

Urbanization is a main driver for the larval ecology of Aedes mosquitoes in arbovirus-endemic settings in south-eastern Côte d'Ivoire

PubMed Central

Koudou, Benjamin G.; Müller, Pie; Malone, David; Tano, Yao; Utzinger, Jürg

2017-01-01

Background Failure in detecting naturally occurring breeding sites of Aedes mosquitoes can bias the conclusions drawn from field studies, and hence, negatively affect intervention outcomes. We characterized the habitats of immature Aedes mosquitoes and explored species dynamics along a rural-to-urban gradient in a West Africa setting where yellow fever and dengue co-exist. Methodology Between January 2013 and October 2014, we collected immature Aedes mosquitoes in water containers in rural, suburban, and urban areas of south-eastern Côte d’Ivoire, using standardized sampling procedures. Immature mosquitoes were reared in the laboratory and adult specimens identified at species level. Principal findings We collected 6,159, 14,347, and 22,974 Aedes mosquitoes belonging to 17, 8, and 3 different species in rural, suburban, and urban environments, respectively. Ae. aegypti was the predominant species throughout, with a particularly high abundance in urban areas (99.374%). Eleven Aedes larval species not previously sampled in similar settings of Côte d’Ivoire were identified: Ae. albopictus, Ae. angustus, Ae. apicoargenteus, Ae. argenteopunctatus, Ae. haworthi, Ae. lilii, Ae. longipalpis, Ae. opok, Ae. palpalis, Ae. stokesi, and Ae. unilineatus. Aedes breeding site positivity was associated with study area, container type, shade, detritus, water turbidity, geographic location, season, and the presence of predators. We found proportionally more positive breeding sites in urban (2,136/3,374, 63.3%), compared to suburban (1,428/3,069, 46.5%) and rural areas (738/2,423, 30.5%). In the urban setting, the predominant breeding sites were industrial containers (e.g., tires and discarded containers). In suburban areas, containers made of traditional materials (e.g., clay pots) were most frequently encountered. In rural areas, natural containers (e.g., tree holes and bamboos) were common and represented 22.1% (163/738) of all Aedes-positive containers, hosting 18.7% of the Aedes fauna. The predatory mosquito species Culex tigripes was commonly sampled, while Toxorhynchites and Eretmapodites were mostly collected in rural areas. Conclusions/significance In Côte d’Ivoire, urbanization is associated with high abundance of Aedes larvae and a predominance of artificial containers as breeding sites, mostly colonized by Ae. aegypti in urban areas. Natural containers are still common in rural areas harboring several Aedes species and, therefore, limiting the impact of systematic removal of discarded containers on the control of arbovirus diseases. PMID:28704434

Urbanized landscapes favored by fig-eating birds increase invasive but not native juvenile strangler fig abundance.

PubMed

Caughlin, Trevor; Wheeler, Jessica H; Jankowski, Jill; Lichstein, Jeremy W

2012-07-01

Propagule pressure can determine the success or failure of invasive plant range expansion. Range expansion takes place at large spatial scales, often encompassing many types of land cover, yet the effect of landscape context on propagule pressure remains largely unknown. Many studies have reported a positive correlation between invasive plant abundance and human land use; increased propagule pressure in these landscapes may be responsible for this correlation. We tested the hypothesis that increased rates of seed dispersal by fig-eating birds, which are more common in urban habitats, result in an increase in invasive strangler fig abundance in landscapes dominated by human land use. We quantified abundance of an invasive species (Ficus microcarpa) and a native species (F. aurea) of strangler fig in plots spanning the entire range of human land use in South Florida, USA, from urban parking lots to native forest. We then compared models that predicted juvenile fig abundance based on distance to adult fig seed sources and fig-eating bird habitat quality with models that lacked one or both of these terms. The best model for juvenile invasive fig abundance included both distance to adult and fig-eating bird habitat terms, suggesting that landscape effects on invasive fig abundance are mediated by seed-dispersing birds. In contrast, the best model for juvenile native fig abundance included only presence/absence of adults, suggesting that distance from individual adult trees may have less effect on seed limitation for a native species compared to an invasive species undergoing range expansion. However, models for both species included significant effects of adult seed sources, implying that juvenile abundance is limited by seed arrival. This result was corroborated by a seed addition experiment that indicated that both native and invasive strangler figs were strongly seed limited. Understanding how landscape context affects the mechanisms of plant invasion may lead to better management techniques. Our results suggest that prioritizing removal of adult trees in sites with high fig-eating bird habitat may be the most effective method to control F. microcarpa abundance.

Biological, social, and urban design factors affecting young street tree mortality in New York City

Treesearch

Jacqueline W.T. Lu; Erika S. Svendsen; Lindsay K. Campbell; Jennifer Greenfeld; Jessie Braden; Kristen King; Nancy Falxa-Raymond

2010-01-01

In dense metropolitan areas, there are many factors including traffic congestion, building development and social organizations that may impact the health of street trees. The focus of this study is to better understand how social, biological and urban design factors affect the mortality rates of newly planted street trees. Prior analyses of street trees planted by the...

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

Treesearch

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...

Urban warming trumps natural enemy regulation of herbivorous pests.

PubMed

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 fitness rather than altered trophic interactions.

Assessing the US Urban Forest Resources

Treesearch

David J. Nowak; Mary H. Noble; Susan M. Sisinni; John F. Dwyer

2001-01-01

Urban areas in the conterminous United States doubled in size between 1969 and 1994, and currently cover 3.5 percent of the total land area and contain more than 75 percent of the US population. Urban areas contain approximately 3.8 billion trees with an average tree canopy cover of 27 percent. The extent and variation of urban forests across the 48 states are explored...

Effects of urban tree canopy loss on land surface temperature magnitude and timing

Treesearch

Arthur Elmes; John Rogan; Christopher Williams; Samuel Ratick; David Nowak; Deborah Martin

2017-01-01

Urban Tree Canopy (UTC) plays an important role in moderating the Surface Urban Heat Island (SUHI) effect, which poses threats to human health due to substantially increased temperatures relative to rural areas. UTC coverage is associated with reduced urban temperatures, and therefore benefits both human health and reducing energy use in cities. Measurement of this...

[Comprehensive evaluation and selection of urban eco-engineering virescent trees in Shenyang City].

PubMed

Lu, Min; Jiang, Fengqi; Li, Yingjie

2004-07-01

Urban virescence eco-engineering is the core of urban eco-environmental construction, which can promote urban sustainable development. In urban virescence eco-engineering, the comprehensive evaluation of ecological adapt-ability and ecological effect of urban plants is the scientific basis of rational application and selection of urban garden plants. The ecological effect and integrative functions of urban virescence eco-engineering depend upon the selection and layout of garden plants. Using the methods of garden expert consultation and evaluation, this paper established systematically integrative evaluation and application indices of virescence plants in Shenyang City, from the aspects of ecological adaptability, ecological effect, beautification effect, resistance to plant diseases and insect pests, anti-pollution and economic results. According to garden experts evaluation and location of Shenyang, 200 sorts of virescence trees were evaluated and classified on the basis of the comprehensive evaluation system of virescence trees, and using cold resistance, drought resistance, barren resistance, plant diseases and insect pests resistance, anti-pollution, ornamental quality and ecological effects as the indexes. The results showed that the number of first rank trees was 58, the second was 93, methods of third was 38, and the fourth was 11, ranked by integrative performance.

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

Treesearch

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)...

Efficient control of air pollution through plants, a cost-effective alternative: studies on Dalbergia sissoo Roxb.

PubMed

Kapoor, C S; Bamniya, B R; Kapoor, K

2013-09-01

Plants can be used as both passive biomonitors and biomitigators in urban and industrial environments to indicate the environmental quality and to ameliorate pollution level in a locality. Many studies reveal that plants are negatively affected by the ambient levels of air pollutants. The present study was conducted to evaluate the impact of air pollution on comparative basis with reference to changes in photosynthetic pigments, plant height, leaves, as well as, biochemical parameters of plants of different sites around Udaipur city receiving varying levels of pollution load. The investigated tree species Dalbergia sissoo Roxb. (Family: Fabaceae) exhibited a reduction in various physiological and biochemical growth parameters that correspond with air pollution levels at different sites. The tree species growing in polluted and control areas were compared with respect to foliar dust load, leaf area, and chlorophyll and total carbohydrate and total protein concentration in the leaves. Our studies suggest that D. sissoo Roxb. can successfully be grown in an area for monitoring air pollution, where it is mild and droughts are common. It will prove as an ideal tree species to control pollution effectively beside acting as a shade tree and being a source of food for birds and animals. By plantation of D. sissoo Roxb., mitigative measure at the polluted sites to control generation of particulate matter and the air quality required can be ensured. Our results also confirm that industrial and vehicular air pollution level in Udaipur city is shifting beyond limits.

Ecological disequilibrium drives insect pest and pathogen accumulation in non-native trees

PubMed Central

Burgess, Treena I.; Le Roux, Johannes J.; Richardson, David M.; Slippers, Bernard; Wingfield, Michael J.

2017-01-01

Abstract Non-native trees have become dominant components of many landscapes, including urban ecosystems, commercial forestry plantations, fruit orchards and as invasives in natural ecosystems. Often, these trees have been separated from their natural enemies (i.e. insects and pathogens) leading to ecological disequilibrium, that is, the immediate breakdown of historically co-evolved interactions once introduced into novel environments. Long-established, non-native tree plantations provide useful experiments to explore the dimensions of such ecological disequilibria. We quantify the status quo of non-native insect pests and pathogens catching up with their tree hosts (planted Acacia, Eucalyptus and Pinus species) in South Africa, and examine which native South African enemy species utilize these trees as hosts. Interestingly, pines, with no confamilial relatives in South Africa and the longest residence time (almost two centuries), have acquired only one highly polyphagous native pathogen. This is in contrast to acacias and eucalypts, both with many native and confamilial relatives in South Africa that have acquired more native pathogens. These patterns support the known role of phylogenetic relatedness of non-native and native floras in influencing the likelihood of pathogen shifts between them. This relationship, however, does not seem to hold for native insects. Native insects appear far more likely to expand their feeding habits onto non-native tree hosts than are native pathogens, although they are generally less damaging. The ecological disequilibrium conditions of non-native trees are deeply rooted in the eco-evolutionary experience of the host plant, co-evolved natural enemies and native organisms from the introduced range. We should expect considerable spatial and temporal variation in ecological disequilibrium conditions among non-native taxa, which can be significantly influenced by biosecurity and management practices. PMID:28013250

Analytical method for the evaluation of the outdoor air contamination by emerging pollutants using tree leaves as bioindicators.

PubMed

Barroso, Pedro José; Martín, Julia; Santos, Juan Luis; Aparicio, Irene; Alonso, Esteban

2018-01-01

In this work, an analytical method, based on sonication-assisted extraction, clean-up by dispersive solid-phase extraction and determination by liquid chromatography-tandem mass spectrometry, has been developed and validated for the simultaneous determination of 15 emerging pollutants in leaves from four ornamental tree species. Target compounds include perfluorinated organic compounds, plasticizers, surfactants, brominated flame retardant, and preservatives. The method was optimized using Box-Behnken statistical experimental design with response surface methodology and validated in terms of recovery, accuracy, precision, and method detection and quantification limits. Quantification of target compounds was carried out using matrix-matched calibration curves. The highest recoveries were achieved for the perfluorinated organic compounds (mean values up to 87%) and preservatives (up to 88%). The lowest recoveries were achieved for plasticizers (51%) and brominated flame retardant (63%). Method detection and quantification limits were in the ranges 0.01-0.09 ng/g dry matter (dm) and 0.02-0.30 ng/g dm, respectively, for most of the target compounds. The method was successfully applied to the determination of the target compounds on leaves from four tree species used as urban ornamental trees (Citrus aurantium, Celtis australis, Platanus hispanica, and Jacaranda mimosifolia). Graphical abstract Analytical method for the biomonitorization of emerging pollutants in outdoor air.

Differences in host choice between the sibling species of treehole mosquitoes Aedes triseriatus and Aedes hendersoni.

PubMed

Nasci, R S

1982-03-01

Adult treehole mosquitoes were collected by vacuum-sweeping of vegetation in urban, suburban, and rural woodlots in northern Indiana. The sibling species Aedes triseriatus and Ae. hendersoni were identified by polyacrylamide gel electrophoresis. Blood meals were identified by the modified precipitin method. Ae. triseriatus fed predominantly on chipmunks and deer, and Ae. hendersoni fed mainly on tree squirrels and racoon. The relative rates of feeding on the major hosts were variable depending on the location of collection, and probably reflected differences in host density. No blood-feeding on humans was detected.

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

NASA Astrophysics Data System (ADS)

Ardila, Juan P.; Bijker, Wietske; Tolpekin, Valentyn A.; Stein, Alfred

2012-04-01

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 to develop a reproducible geographic object-based image analysis (GEOBIA) methodology to locate and delineate tree crowns in urban areas using high resolution imagery. We propose a GEOBIA approach that considers the spectral, spatial and contextual characteristics of tree objects in the urban space. The study presents classification rules that exploit object features at multiple segmentation scales modifying the labeling and shape of image-objects. The GEOBIA methodology was implemented on QuickBird images acquired over the cities of Enschede and Delft (The Netherlands), resulting in an identification rate of 70% and 82% respectively. False negative errors concentrated on small trees and false positive errors in private gardens. The quality of crown boundaries was acceptable, with an overall delineation error <0.24 outside of gardens and backyards.

Levels of selected trace elements in Scots pine (Pinus sylvestris L.), silver birch (Betula pendula L.), and Norway maple (Acer platanoides L.) in an urbanized environment.

PubMed

Kosiorek, Milena; Modrzewska, Beata; Wyszkowski, Mirosław

2016-10-01

The aim of the study was to determine the concentrations of selected trace elements in needles and bark of Scots pine (Pinus sylvestris L.), leaves and bark of silver birch (Betula pendula L.), and Norway maple (Acer platanoides L.), as well as in the soil in which the trees grew, depending on their localization and hence the distribution of local pollution sources. The content of trace elements in needles of Scots pine, leaves of silver birch, and Norway maple and in bark of these trees depended on the location, tree species, and analyzed organ. The content of Fe, Mn, and Zn in needles, leaves, and bark of the examined tree species was significantly higher than that of the other elements. The highest average content of Fe and Mn was detected in leaves of Norway maple whereas the highest average content of Zn was found in silver birch leaves. The impact of such locations as the center of Olsztyn or roadside along Road 51 on the content of individual elements tended to be more pronounced than the influence of the other locations. The influence of the sampling sites on the content of trace elements in tree bark was less regular than the analogous effect in needles and leaves. Moreover, the relevant dependences were slightly different for Scots pine than for the other two tree species. The concentrations of heavy metals determined in the soil samples did not exceed the threshold values set in the Regulation of the Minister for the Environment, although the soil along Road 51 and in the center of Olsztyn typically had the highest content of these elements. There were also significant correlations between the content of some trace elements in soil and their accumulation in needles, leaves, and bark of trees.

Increase in platinum group elements in Mexico City as revealed from growth rings of Taxodium mucronatum ten.

PubMed

Morton-Bermea, Ofelia; Beramendi-Orosco, Laura; Martínez-Reyes, Ángeles; Hernández-Álvarez, Elizabeth; González-Hernández, Galia

2016-02-01

Tree rings may be used as indicators of contamination events providing information on the chronology and the elemental composition of the contamination. In this framework, we report PGEs enrichment in growth rings of Taxodium mucronatum ten for trees growing in the central area of Mexico City as compared to trees growing in a non-urban environment. Concentrations of PGE were determined by ICP-MS analysis on microwave-digested tree rings. The element found in higher concentrations was Pd (1.13-87.98 μg kg(-1)), followed by Rh (0.28-36.81 μg kg(-1)) and Pt (0.106-7.21 μg kg(-1)). The concentration trends of PGEs in the tree-ring sequences from the urban area presented significant correlation values when comparing between trees (r between 0.618 and 0.98, P < 0.025) and between elements within individual trees (r between 0.76 and 0.994, P < 0.01). Furthermore, a clear increase was observed for rings after 1997, with enrichment of up to 60 times the mean concentration found for the sequence from the non-urban area and up to 40 times the mean concentration for the pre-1991 period in the urban trees. These results also demonstrate the feasibility of applying T. mucronatum ten to be used as a bioindicator of the increase in PGE in urban environments.

Species arboreal as a bioindicator of the environmental pollution: Analysis by SR-TXRF

NASA Astrophysics Data System (ADS)

de Vives, Ana Elisa Sirito; Moreira, Silvana; Brienza, Sandra Maria Boscolo; Medeiros, Jean Gabriel S.; Filho, Mario Tomazello; Zucchi, Orghêda Luiza Araújo Domingues; do Nascimento Filho, Virgilio Franco; Barroso, Regina Cely

2007-08-01

This paper aims to study the environmental pollution in the tree development, in order to evaluate its use as bioindicator in urban and countrysides. The sample collection was carried out in Piracicaba city, São Paulo State, that presents high level of environmental contamination in water, soil and air, due to industrial activities, vehicle combustion, sugar-cane leaves burning in the harvesting, etc. The species Caesalpinia peltophoroides ("Sibipiruna") was selected because it is often used in urban arborization. Synchrotron radiation X-ray fluorescence technique (SR-TXRF) was employed to identify and quantify the elements and metals of nutritional and toxicological importance in the wood samples. The analysis was performed in the Brazilian Synchrotron Light Source Laboratory, using a white beam for excitation and an Si(Li) detector for X-ray detection. In several samples were quantified P, K, Ca, Ti, Fe, Sr, Ba and Pb elements.

Atmospheric Inputs of Nitrogen, Carbon, and Phosphorus across an Urban Area: Unaccounted Fluxes and Canopy Influences

NASA Astrophysics Data System (ADS)

Decina, Stephen M.; Templer, Pamela H.; Hutyra, Lucy R.

2018-02-01

Rates of atmospheric deposition are declining across the United States, yet urban areas remain hotspots of atmospheric deposition. While past studies show elevated rates of inorganic nitrogen (N) deposition in cities, less is known about atmospheric inputs of organic N, organic carbon (C), and organic and inorganic phosphorus (P), all of which can affect ecosystem processes, water quality, and air quality. Further, the effect of the tree canopy on amounts and forms of nutrients reaching urban ground surfaces is not well-characterized. We measured growing season rates of total N, organic C, and total P in bulk atmospheric inputs, throughfall, and soil solution around the greater Boston area. We found that organic N constitutes a third of total N inputs, organic C inputs are comparable to rural inputs, and inorganic P inputs are 1.2 times higher than those in sewage effluent. Atmospheric inputs are enhanced two-to-eight times in late spring and are elevated beneath tree canopies, suggesting that trees augment atmospheric inputs to ground surfaces. Additionally, throughfall inputs may directly enter runoff when trees extend above impervious surfaces, as is the case with 26.1% of Boston's tree canopy. Our results indicate that the urban atmosphere is a significant source of elemental inputs that may impact urban ecosystems and efforts to improve water quality, particularly in terms of P. Further, as cities create policies encouraging tree planting to provide ecosystem services, locating trees above permeable surfaces to reduce runoff nutrient loads may be essential to managing urban biogeochemical cycling and water quality.

Modeling of urban trees' effects on reducing human exposure to UV radiation in Seoul, Korea

Treesearch

Hang Ryeol Na; Gordon M. Heisler; David J. Nowak; Richard H. Grant

2014-01-01

A mathematical model isconstructed for quantifying urban trees’ effects on mitigating the intensity of ultraviolet (UV) radiation on the ground within different landuse types across a city. The model is based upon local field data, meteorological data and equations designed to predict the reduced UV fraction due to trees at the ground level. Trees in Seoul, Korea (2010...

Difficulties with estimating city-wide urban forest cover change from national, remotely-sensed tree canopy maps

Treesearch

Jeffrey T. Walton

2008-01-01

Two datasets of percent urban tree canopy cover were compared. The first dataset was based on a 1991 AVHRR forest density map. The second was the US Geological Survey's National Land Cover Database (NLCD) 2001 sub-pixel tree canopy. A comparison of these two tree canopy layers was conducted in 36 census designated places of western New York State. Reference data...

Syracuse urban forest master plan: guiding the city's forest resource into the 21st century

Treesearch

David J. Nowak; Paul R. O' Connor; [Compilers

2001-01-01

The Syracuse Urban Forest Master Plan is one of the most comprehensive urban forest assessments ever developed for a city. This report combines a high-resolution digital urban cover map with field vegetation sampling data from all land uses, a 100-percent street-tree inventory, a survey of city residents regarding desirable and undesirable tree characteristics and...

Data quality in citizen science urban tree inventories

Treesearch

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...

City of Charleston, South Carolina Municipal Forest Resource Analysis

Treesearch

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

2006-01-01

Charleston, a charming Southern city appreciated for its rich history and culture, maintains trees as an integral component of the urban infrastructure (Figure 1). Research indicates that healthy trees can lessen impacts associated with the built environment by reducing stormwater runoff, energy consumption, and air pollutants. Trees improve urban life, making...

City of Charlotte, North Carolina Municipal Forest Resource Analysis

Treesearch

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

2005-01-01

Charlotte, a vibrant Southern city appreciated for its rich history and cultural wealth, maintains trees as an integral component of the urban infrastructure (Figure 1). Research indicates that healthy trees can lessen impacts associated with the built environment by reducing stormwater runoff, energy consumption, and air pollutants. Trees improve urban life, making...

Data management for urban tree monitoring -- software requirements

Treesearch

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...

Potential tree species for use in the restoration of unsanitary landfills.

PubMed

Kim, Kee Dae; Lee, Eun Ju

2005-07-01

Given that they represent the most economical option for disposing of refuse, waste landfills are widespread in urban areas. However, landfills generate air and water pollution and require restoration for landscape development. A number of unsanitary waste landfills have caused severe environmental problems in developing countries. This study aimed to investigate the colonization status of different tree species on waste landfills to assess their potential for restoring unsanitary landfills in South Korea. Plot surveys were conducted using 10 x 10-m quadrats at seven waste landfill sites: Bunsuri, Dugiri, Hasanundong, Gomaeri, Kyongseodong, Mojeonri, and Shindaedong. We determined the height, diameter at breast height (DBH), and number of tree species in the plots, and enumerated all saplings < or =1 m high. Because black locust, Robinia pseudoacacia, was the dominant tree species in the waste landfills, we measured the distance from the presumed mother plant (i.e., the tallest black locust in a patch), height, and DBH of all individuals in black locust patches to determine patch structure. Robinia pseudoacacia, Salix koreensis, and Populus sieboldii formed canopy layers in the waste landfills. The basal area of black locust was 1.51 m(2)/ha, and this species had the highest number of saplings among all tree species. The diameter of the black locust patches ranged from 3.71 to 11.29 m. As the patch diameter increased, the number of regenerated saplings also tended to increase, albeit not significantly. Black locust invaded via bud banks and spread clonally in a concentric pattern across the landfills. This species grew well in the dry habitat of the landfills, and its growth rate was very high. Furthermore, black locust has the ability to fix nitrogen symbiotically; it is therefore considered a well-adapted species for waste landfills. Eleven woody species were selected for screening: Acer palmatum, Albizzia julibrissin, Buxus microphylla var. koreana, Ginkgo biloba, Hibiscus syriacus, Koelreuteria paniculata, Ligustrum obtusifolium, Liriodendron tulipifera, Pinus koraiensis, Pinus thunbergii, and Sophora japonica. As a result of a comparison of the total ratio (sum of shoot extension and diameter growth at the landfill relative to a reference site) and mortality, six species (Liriodendron tulipifera, Albizzia julibrissin, Ligustrum obtusifolium, Buxus microphylla var. koreana, Hibiscus syriacus, and Sophora japonica), which had a total ratio >1 and experienced low mortality, are recommended as potentially suitable species for waste landfill remediation. We suggest that mixed plantations of ubiquitous adaptable species and naturally occurring black locust will enhance the landscape through synergistic effects.

Evaluation of an urban canopy model in a tropical city: the role of tree evapotranspiration

NASA Astrophysics Data System (ADS)

Liu, Xuan; Li, Xian-Xiang; Harshan, Suraj; Roth, Matthias; Velasco, Erik

2017-09-01

A single layer urban canopy model (SLUCM) with enhanced hydrologic processes, is evaluated in a tropical city, Singapore. The evaluation was performed using an 11 month offline simulation with the coupled Noah land surface model/SLUCM over a compact low-rise residential area. Various hydrological processes are considered, including anthropogenic latent heat release, and evaporation from impervious urban facets. Results show that the prediction of energy fluxes, in particular latent heat flux, is improved when these processes were included. However, the simulated latent heat flux is still underestimated by ∼40%. Considering Singapore’s high green cover ratio, the tree evapotranspiration process is introduced into the model, which significantly improves the simulated latent heat flux. In particular, the systematic error of the model is greatly reduced, and becomes lower than the unsystematic error in some seasons. The effect of tree evapotranspiration on the urban surface energy balance is further demonstrated during an unusual dry spell. The present study demonstrates that even at sites with relatively low (11%) tree coverage, ignoring evapotranspiration from trees may cause serious underestimation of the latent heat flux and atmospheric humidity. The improved model is also transferable to other tropical or temperate regions to study the impact of tree evapotranspiration on urban climate.

Patterns of woody plant invasion in an Argentinean coastal grassland

NASA Astrophysics Data System (ADS)

Alberio, Constanza; Comparatore, Viviana

2014-01-01

Coastal dune grasslands are fragile ecosystems that have historically been subjected to various types of uses and human activities. In Buenos Aires Province (Argentina), these areas are frequently afforested for urban and touristic development. The introduction and subsequent spread of exotic tree species is one of the main threats to conservation of natural grasslands as invasive trees strongly transform their structure and composition. The aim of this study was to identify patterns of woody plant invasion comparing plant communities and environmental variables between invaded and non-invaded areas surrounding the coastal village of Mar Azul, Argentina. Coastal grasslands in this area are being invaded by Populus alba (white poplar) and Acacia longifolia (coast wattle). The height of the saplings and the richness of the accompanying vegetation were evaluated in relation to the distance from the edge of the mature tree patches. Also, the cover, richness and diversity of all species in the invaded and non-invaded areas were measured, as well as soil pH, temperature and particle size. Negative correlations were found between the height of the saplings and distance to mature tree patches in all areas. The richness of the accompanying vegetation was negatively and positively correlated with the distance from the poplar and acacia area, respectively. The most abundant native species was Cortaderia selloana. Less cover, richness and diversity of native plant species and greater soil particle size were found in invaded areas, where the proportion of bare soil was higher. Also, a higher proportion of leaf litter in the invaded areas was registered. The results emphasize the invasive capacity of P. alba and A. longifolia advancing on the native communities and reducing their richness. Knowledge of the impact of invasive woody plants in coastal grasslands is important to design active management strategies for conservation purposes.

Identifying the rooted species tree from the distribution of unrooted gene trees under the coalescent.

PubMed

Allman, Elizabeth S; Degnan, James H; Rhodes, John A

2011-06-01

Gene trees are evolutionary trees representing the ancestry of genes sampled from multiple populations. Species trees represent populations of individuals-each with many genes-splitting into new populations or species. The coalescent process, which models ancestry of gene copies within populations, is often used to model the probability distribution of gene trees given a fixed species tree. This multispecies coalescent model provides a framework for phylogeneticists to infer species trees from gene trees using maximum likelihood or Bayesian approaches. Because the coalescent models a branching process over time, all trees are typically assumed to be rooted in this setting. Often, however, gene trees inferred by traditional phylogenetic methods are unrooted. We investigate probabilities of unrooted gene trees under the multispecies coalescent model. We show that when there are four species with one gene sampled per species, the distribution of unrooted gene tree topologies identifies the unrooted species tree topology and some, but not all, information in the species tree edges (branch lengths). The location of the root on the species tree is not identifiable in this situation. However, for 5 or more species with one gene sampled per species, we show that the distribution of unrooted gene tree topologies identifies the rooted species tree topology and all its internal branch lengths. The length of any pendant branch leading to a leaf of the species tree is also identifiable for any species from which more than one gene is sampled.

Modeling the effects of urban vegetation on air pollution

Treesearch

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...

Gaseous polycyclic aromatic hydrocarbon concentrations are higher in urban forests than adjacent open areas during summer but not in winter--Exploratory study.

PubMed

Viippola, Viljami; Rantalainen, Anna-Lea; Yli-Pelkonen, Vesa; Tervo, Peatta; Setälä, Heikki

2016-01-01

While the potential of plants to uptake polycyclic aromatic hydrocarbons (PAHs) is widely acknowledged, empirical evidence of the effects of this process on local atmospheric PAH concentrations and human health is tenuous. We measured gaseous PAH concentrations using passive samplers in urban tree-covered areas and adjacent open, treeless areas in a near-road environment in Finland to gain information on the ability of urban vegetation to improve air quality. The ability of urban, mostly deciduous, vegetation to affect PAHs was season dependent: during summer, concentrations were significantly higher in tree-covered areas, while in the fall, concentrations in open areas exceeded those in tree-covered areas. During winter, concentrations in tree-covered areas were either lower or did not differ from those in open areas. Results of this study imply that the commonly believed notion that trees unequivocally improve air quality does not apply to PAHs studied here. Copyright © 2015 Elsevier Ltd. All rights reserved.

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

Treesearch

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...

A dynamic processes study of PM retention by trees under different wind conditions.

PubMed

Xie, Changkun; Kan, Liyan; Guo, Jiankang; Jin, Sijia; Li, Zhigang; Chen, Dan; Li, Xin; Che, Shengquan

2018-02-01

Particulate matter (PM) is one of the most serious environmental problems, exacerbating respiratory and vascular illnesses. Plants have the ability to reduce non-point source PM pollution through retention on leaves and branches. Studies of the dynamic processes of PM retention by plants and the mechanisms influencing this process will help to improve the efficiency of urban greening for PM reduction. We examined dynamic processes of PM retention and the major factors influencing PM retention by six trees with different branch structure characteristics in wind tunnel experiments at three different wind speeds. The results showed that the changes of PM numbers retained by plant leaves over time were complex dynamic processes for which maximum values could exceed minimum values by over 10 times. The average value of PM measured in multiple periods and situations can be considered a reliable indicator of the ability of the plant to retain PM. The dynamic processes were similar for PM 10 and PM 2.5 . They could be clustered into three groups simulated by continually-rising, inverse U-shaped, and U-shaped polynomial functions, respectively. The processes were the synthetic effect of characteristics such as species, wind speed, period of exposure and their interactions. Continually-rising functions always explained PM retention in species with extremely complex branch structure. Inverse U-shaped processes explained PM retention in species with relatively simple branch structure and gentle wind. The U-shaped processes mainly explained PM retention at high wind speeds and in species with a relatively simple crown. These results indicate that using plants with complex crowns in urban greening and decreasing wind speed in plant communities increases the chance of continually-rising or inverse U-shaped relationships, which have a positive effect in reducing PM pollution. Copyright © 2017 Elsevier Ltd. All rights reserved.

Multiple health benefits of urban tree canopy: The mounting evidence for a green prescription.

PubMed

Ulmer, Jared M; Wolf, Kathleen L; Backman, Desiree R; Tretheway, Raymond L; Blain, Cynthia Ja; O'Neil-Dunne, Jarlath Pm; Frank, Lawrence D

2016-11-01

The purpose of this study was to enhance the understanding of the health-promoting potential of trees in an urbanized region of the United States. This was done using high-resolution LiDAR and imagery data to quantify tree cover within 250m of the residence of 7910 adult participants in the California Health Interview Survey, then testing for main and mediating associations between tree cover and multiple health measures. The results indicated that more neighborhood tree cover, independent from green space access, was related to better overall health, primarily mediated by lower overweight/obesity and better social cohesion, and to a lesser extent by less type 2 diabetes, high blood pressure, and asthma. These findings suggest an important role for trees and nature in improving holistic population health in urban areas. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

NASA Astrophysics Data System (ADS)

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.

High Resolution Spatial Analysis of Habitat Preference of Aedes Albopictus (Diptera: Culicidae) in an Urban Environment.

PubMed

Cianci, Daniela; Hartemink, Nienke; Zeimes, Caroline B; Vanwambeke, Sophie O; Ienco, Annamaria; Caputo, Beniamino

2015-05-01

Over the past decades, the Asian tiger mosquito (Aedes albopictus (Skuse, 1895)) has emerged in many countries, and it has colonized new environments, including urban areas. The species is a nuisance and a potential vector of several human pathogens, and a better understanding of the habitat preferences of the species is needed for help in successful prevention and control. So far, the habitat preference in urban environments has not been studied in Southern European cities. In this paper, spatial statistical models were used to evaluate the relationship between egg abundances and land cover types on the campus of Sapienza University in Rome, which is taken as an example of a European urban habitat. Predictor variables included land cover types, classified in detail on a high resolution image, as well as solar radiation and month of capture. The models account for repeated measures in the same trap and are adjusted for meteorological circumstances. Vegetation and solar radiation were found to be positively related to the number of eggs. More specifically, trees were positively related to the number of eggs and the relationship with grass was negative. These findings are consistent with the species' known preference for shaded areas. The unexpected positive relationship with solar radiation is amply discussed in the paper. This study represents a first step toward a better understanding of the spatial distribution of Ae. albopictus in urban environments. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Water relations of coast redwood planted in the semi-arid climate of southern California.

PubMed

Litvak, Elizaveta; McCarthy, Heather R; Pataki, Diane E

2011-08-01

Trees planted in urban landscapes in southern California are often exposed to an unusual combination of high atmospheric evaporative demand and moist soil conditions caused by irrigation. The water relations of species transplanted into these conditions are uncertain. We investigated the water relations of coast redwood (Sequoia sempervirens) planted in the urbanized semi-arid Los Angeles Basin, where it often experiences leaf chlorosis and senescence. We measured the sap flux (J(O)) and hydraulic properties of irrigated trees at three sites in the Los Angeles region. We observed relatively strong stomatal regulation in response to atmospheric vapour pressure deficit (D; J(O) saturated at D < 1 kPa), and a linear response of J(O) to photosynthetically active radiation. Total tree water use by coast redwood was relatively low, with plot-level transpiration rates below 1 mm d(-1) . There was some evidence of xylem cavitation during the summer, which appeared to be reversed in fall and early winter. We conclude that water stress was not a direct factor in causing leaf chlorosis and senescence as has been proposed. Instead, the relatively strong stomatal control that is adaptive in the native habitat of coast redwood may lead to carbon limitation and other stresses in semi-arid, irrigated habitats. © 2011 Blackwell Publishing Ltd.

The influence of tree traits and storm event characteristics on stemflow production from isolated deciduous trees in an urban park

NASA Astrophysics Data System (ADS)

Carlyle-Moses, D. E.; Schooling, J. T.

2014-12-01

Urban tree canopy processes affect the volume and biogeochemistry of inputs to the hydrological cycle in cities. We studied stemflow from 37 isolated deciduous trees in an urban park in Kamloops, British Columbia which has a semi-arid climate dominated by small precipitation events. Precipitation and stemflow were measured on an event basis from June 12, 2012 to November 3, 2013. To clarify the effect of canopy traits on stemflow thresholds, rates, yields, percent, and funneling ratios, we analyzed branch angles, bark roughness, tree size, cover, leaf size, and branch and leader counts. High branch angles promoted stemflow in all trees, while bark roughness influenced stemflow differently for single- and multi-leader trees. The association between stemflow and numerous leaders deserves further study. Columnar-form trees often partitioned a large percentage of precipitation into stemflow, with event-scale values as high as 27.9 % recorded for an Armstrong Freeman Maple (Acer x freemanii 'Armstrong'). Under growing-season conditions funneling ratios as high as 196.9 were derived for an American Beech (Fagus grandifolia) individual. Among meteorological variables, rain depth was strongly correlated with stemflow yields; intra-storm break duration, rainfall intensity, rainfall inclination, wind speed, and vapour pressure deficit also played roles. Greater stemflow was associated with leafless canopies and with rain or mixed events versus snow. Results can inform climate-sensitive selection and siting of urban trees towards integrated rainwater management. For example, previous studies suggest that the reduction in storm-water generation by urban trees is accomplished through canopy interception loss alone. However, trees that partition large quantities of precipitation canopy-drainage as stemflow to the base of their trunks, where it has the potential to infiltrate into the soil media rather than fall on impervious surfaces as throughfall, may assist in reducing stormwater flow.

Urban landscapes and the western drought

NASA Astrophysics Data System (ADS)

Pataki, D. E.

2015-12-01

Cities in the western U.S. are heavily irrigated and have increasingly been the focus of water conservation measures. Even cities that previously relied only on voluntary reductions in outdoor water use have been employing stricter mandates to limit irrigation. These cities are in a period of transition and the outcomes are far from certain. There are many tradeoffs in the environmental and social consequences of different urban water management strategies. Here we review recent work studying these tradeoffs in cities of southern California and Utah. We have measured the water use of different types of landscapes ranging from turfgrass to urban trees to xeriscapes. Unshaded turfgrass shows evapotranspiration (ET) rates close to potential ET; however, shaded turfgrass uses substantially less water. On the other hand, plants used in xeriscapes may have surprisingly high transpiration rates if they are heavily watered. In addition, unshaded xeriscapes may substantially alter surface energy balance and have unintended consequences for urban climate. Through whole tree sap flux measurements and scaling of ET estimates, we have found that urban trees generally use less water than turfgrass, and provide additional cooling benefits through interception of radiation. Current measures to reduce outdoor water use through irrigation restrictions and turfgrass removal programs do not include safeguards to ensure that urban trees receive adequate irrigation, and the future of urban tree canopies in western cities is highly uncertain. Although trees and other deep-rooted vegetation may require less irrigation than turfgrass and better withstand periods of drought, this vegetation must still be appropriate managed with water inputs informed by an understanding of plant water relations and urban subsurface hydrology. On the current trajectory, cities may see a substantial loss of vegetative cover and leaf area unless an understanding of ecohydrology is better integrated into strategies for long-term stewardship of urban landscapes in a changing climate.

Watershed Watch Undergraduate Research Projects: Monitoring Environmental Impacts on Tree Growth - Urban Development and Hurricanes

NASA Astrophysics Data System (ADS)

Rock, B. N.; Hale, S.

2009-12-01

Watershed Watch (NSF 0525433) is designed to engage early undergraduate students from two-year and four-year colleges in student-driven full inquiry-based instruction in the biogeosciences. Program goals for Watershed Watch are to test if inquiry-rich student-driven projects sufficiently engage undeclared students (or noncommittal STEM majors) to declare a STEM major (or remain with their STEM major). The program is a partnership between two four-year campuses - the University of New Hampshire (UNH), and Elizabeth City State University (ECSU, in North Carolina); and two two-year campuses - Great Bay Community College (GBCC, in New Hampshire) and the College of the Albemarle (COA, in North Carolina). Two Watershed Watch students from the 2009 Summer Research Institute (SRI), held on the ECSU campus, August 3-14, 2009 investigated the use of wood cores collected from loblolly pine (Pinus taeda) and bald cypress (Taxodium distichum). One student team studied the possible impacts of urban development on tree growth, focusing on the use of dendrochronology to assess the effect of environmental factors on the trees. Tree cores and foliar samples were collected at the ECSU Outdoor Classroom and compared with the same species from the Great Dismal Swamp (GDS) in Virginia. The main targets of this experiment were one aquatic tree, the bald cypress, and a land based tree, the loblolly pine. This allowed us to compare an urbanized area (ECSU) with a more natural setting (GDS) to evaluate factors impacting tree growth. This experiment suggests that there may be potentially harmful impacts of an urban environment with the data that at ECSU. The growth rings of the ECSU campus tree cores are noticeably narrow, especially in the loblolly pine from the ECSU outdoor classroom, and multiple fluctuations in more recent tree rings of the bald cypress in the ECSU campus. Growth ring compression, beginning approximately in 1956 in 100-year old loblolly pines, corresponds in timing with the nearby construction of two student dormitories within 100 feet of the trees. The other student team studied cores for evidence of possible impacts from four recent hurricanes (Isabel, category 5, 2003; Floyd, category 4, 1999; Bonnie, category 3, 1998; and Fran, Category 3, 1996) on trees from the Alligator River (near Cape Hatteras, NC) and from the ECSU campus (well inland). Cores were evaluated for the presence or absence of false growth rings that could be the result of saltwater impoundment associated with storm surges. False growth rings were seen in the cores of loblolly pine from the Alligator River site, but only for the years 2003 and 1999. No false growth rings were seen in the cores of loblolly pine from the ECSU campus. Both hurricanes Isabel and Floyd were stronger storms and had higher storm surges (8-10 ft) than either Bonnie or Fran (storm surges of 3-5 feet). The team hypothesized that the false growth rings were related to the impacts of the two stronger storms.

Preventing Establishment: An Inventory of Introduced Plants in Puerto Villamil, Isabela Island, Galapagos

PubMed Central

Guézou, Anne; Pozo, Paola; Buddenhagen, Christopher

2007-01-01

As part of an island-wide project to identify and eradicate potentially invasive plant species before they become established, a program of inventories is being carried out in the urban and agricultural zones of the four inhabited islands in Galapagos. This study reports the results of the inventory from Puerto Villamil, a coastal village representing the urban zone of Isabela Island. We visited all 1193 village properties to record the presence of the introduced plants. In addition, information was collected from half of the properties to determine evidence for potential invasiveness of the plant species. We recorded 261 vascular taxa, 13 of which were new records for Galapagos. Most of the species were intentionally grown (cultivated) (73.3%) and used principally as ornamentals. The most frequent taxa we encountered were Cocos nucifera (coconut tree) (22.1%) as a cultivated plant and Paspalum vaginatum (salt water couch) (13.2%) as a non cultivated plant. In addition 39 taxa were naturalized. On the basis of the invasiveness study, we recommend five species for eradication (Abutilon dianthum, Datura inoxia, Datura metel, Senna alata and Solanum capsicoides), one species for hybridization studies (Opuntia ficus-indica) and three species for control (Furcraea hexapetala, Leucaena leucocephala and Paspalum vaginatum). PMID:17940606

Prioritizing preferable locations for increasing urban tree canopy in New York City

Treesearch

Dexter Locke; J. Morgan Grove; Jacqueline W.T. Lu; Austin Troy; Jarlath P.M. O' Neil-Dunne; Brian Beck

2010-01-01

This paper presents a set of Geographic Information System (GIS) methods for identifying and prioritizing tree planting sites in urban environments. It uses an analytical approach created by a University of Vermont service-learning class called "GIS Analysis of New York City's Ecology" that was designed to provide research support to the MillionTreesNYC...

Assessing potential urban tree planting sites in the Piedmont of the Unitied States: A comparison of methods

Treesearch

Krista Merry; Jacek Siry; Pete Bettinger; Michael Bowker

2013-01-01

There is a growing interest of late to enhance our ability to reduce carbon dioxide levels in the atmosphere through tree growth. Although the spread of development in urban areas may, in some cases, cause a reduction in forest cover, there may be opportunities to establish additional trees in open...

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

Treesearch

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...

KSC-99pc0137

NASA Image and Video Library

1999-01-29

KENNEDY SPACE CENTER, FLA. -- An Eastern gray squirrel pauses in its daily search for food in the Merritt Island National Wildlife Refuge, which shares a boundary with Kennedy Space Center. The Eastern gray squirrel is found in wooded, suburban, and urban areas statewide. It nests in tree hollows or leaf nests in treetops. It forages during the day, mainly early morning and late afternoon, both on the ground and in trees, living on a diet of acorns, nuts, fruits, berries, insects, and bird eggs. Food plants include cypress, buckeyes, elms, grapes, tulip trees, mulberries, and tupelo. It breeds in late winter or early spring and again in late spring or summer, bearing two to six young. The eastern gray squirrel chatters when disturbed. The 92,000-acre wildlife refuge is a habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles

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

Treesearch

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,...

Analyzing growth and mortality in a subtropical urban forest ecosystem

Treesearch

Alicia B. Lawrence; Fancisco J. Escobedo; Christina L. Staudhammera; Wayne Zipperer Zipperer

2012-01-01

Information on urban tree growth, mortality and in-growth is currently being used to estimate urban forest structure changes and ecosystem services such as carbon sequestration. This study reports on tree diameter growth and mortality in 65 plots distributed among four land use categories, which were established in 2005/2006 in Gainesville, Florida, USA and were re-...

Air pollution removal by urban forests in Canada and its effect on air quality and human health

Treesearch

David J. Nowak; Satoshi Hirabayashi; Marlene Doyle; Mark McGovern; Jon Pasher

2018-01-01

Urban trees perform a number of ecosystem services including air pollution removal, carbon sequestration, cooling air temperatures and providing aesthetic beauty to the urban landscape. Trees remove air pollution by intercepting particulate matter on plant surfaces and absorbing gaseous pollutants through the leaf stomata. Computer simulations with local environmental...

Infection of Ixodes ricinus by Borrelia burgdorferi sensu lato in peri-urban forests of France

PubMed Central

Perthame, Emeline; Sertour, Natacha; Garnier, Martine; Godard, Vincent

2017-01-01

Lyme borreliosis is the most common tick-borne disease in the northern hemisphere. In Europe, it is transmitted by Ixodes ticks that carry bacteria belonging to the Borrelia burgdorferi sensu lato complex. The objective of this work was to explore eco-epidemiological factors of Lyme borreliosis in peri-urban forests of France (Sénart, Notre-Dame and Rambouillet). We investigated whether the introduction of Tamias sibiricus in Sénart could alter the density of infected ticks. Moreover, the density and tick infection were investigated according to the tree species found in various patches of Sénart forest. For this purpose, ticks were sampled during 3 years. In the Sénart forest, the density of nymph and adult ticks showed no significant difference between 2008, 2009 and 2011. The nymph density varied significantly as a function of the month of collection. Regarding the nymphs, a higher rate of infection and infected density were found in 2009. Plots with chipmunks (C) presented a lower density of both nymphs and adult ticks than plots without chipmunks (NC) did. A higher rate of infection of nymphs with Borrelia was seen in C plots. The prevalence of the various species of Borrelia was also found to vary between C and NC plots with the year of the collect. The presence of chestnut trees positively influenced the density of both nymphs and adults. The infected nymph density showed a significant difference depending on the peri-urban forest studied, Sénart being higher than Rambouillet. The prevalence of Borrelia species also differed between the various forests studied. Concerning the putative role that Tamias sibiricus may play in the transmission of Borrelia, our results suggest that its presence is correlated with a higher rate of infection of questing ticks by Borrelia genospecies and if its population increases, it could play a significant role in the risk of transmission of Lyme borreliosis. PMID:28846709

Infection of Ixodes ricinus by Borrelia burgdorferi sensu lato in peri-urban forests of France.

PubMed

Marchant, Axelle; Le Coupanec, Alain; Joly, Claire; Perthame, Emeline; Sertour, Natacha; Garnier, Martine; Godard, Vincent; Ferquel, Elisabeth; Choumet, Valerie

2017-01-01

Lyme borreliosis is the most common tick-borne disease in the northern hemisphere. In Europe, it is transmitted by Ixodes ticks that carry bacteria belonging to the Borrelia burgdorferi sensu lato complex. The objective of this work was to explore eco-epidemiological factors of Lyme borreliosis in peri-urban forests of France (Sénart, Notre-Dame and Rambouillet). We investigated whether the introduction of Tamias sibiricus in Sénart could alter the density of infected ticks. Moreover, the density and tick infection were investigated according to the tree species found in various patches of Sénart forest. For this purpose, ticks were sampled during 3 years. In the Sénart forest, the density of nymph and adult ticks showed no significant difference between 2008, 2009 and 2011. The nymph density varied significantly as a function of the month of collection. Regarding the nymphs, a higher rate of infection and infected density were found in 2009. Plots with chipmunks (C) presented a lower density of both nymphs and adult ticks than plots without chipmunks (NC) did. A higher rate of infection of nymphs with Borrelia was seen in C plots. The prevalence of the various species of Borrelia was also found to vary between C and NC plots with the year of the collect. The presence of chestnut trees positively influenced the density of both nymphs and adults. The infected nymph density showed a significant difference depending on the peri-urban forest studied, Sénart being higher than Rambouillet. The prevalence of Borrelia species also differed between the various forests studied. Concerning the putative role that Tamias sibiricus may play in the transmission of Borrelia, our results suggest that its presence is correlated with a higher rate of infection of questing ticks by Borrelia genospecies and if its population increases, it could play a significant role in the risk of transmission of Lyme borreliosis.

An evaluation of bur oak (Quercus macrocarpa) decline in the urban forest of Winnipeg, Manitoba, Canada

USGS Publications Warehouse

Catton, H.A.; St., George; Remphrey, W.R.

2007-01-01

Winnipeg, Manitoba, Canada, has a large, indigenous population of bur oak (Quercus macrocarpa Michx.). In the 1980s, many of these trees were showing signs of decline, a disease caused by a complex of abiotic and secondary biotic stressing agents. Potential causal factors were investigated by comparing various aspects of 120 bur oaks visually rated as healthy or declined based on crown dieback levels. The results indicated that many selected bur oak trees predated surrounding urban development and that declined trees were significantly older with more severe stem wounds and competition from surrounding trees than healthy specimens. Average annual growth ring widths of healthy and declined trees were similar in the early part of the 20th century. However, decline actually began decades before symptoms were noticed, coinciding with a period of in tense city-wide urban development, as growth of declined trees was slower than that of healthy trees beginning sporadically in the 1940s and consistently from 1974 to 2001. During the early years of decline, the year-by-year separation in ring width between the two categories was significantly positively related to precipitation levels. This suggested that in wet years, declined trees may have been surrounded by unfavorable water-logged soils, possibly as a result of natural drainage patterns being impeded by urban development. ?? 2007 International Society of Arboriculture.

Automatic extraction of tree crowns from aerial imagery in urban environment

NASA Astrophysics Data System (ADS)

Liu, Jiahang; Li, Deren; Qin, Xunwen; Yang, Jianfeng

2006-10-01

Traditionally, field-based investigation is the main method to investigate greenbelt in urban environment, which is costly and low updating frequency. In higher resolution image, the imagery structure and texture of tree canopy has great similarity in statistics despite the great difference in configurations of tree canopy, and their surface structures and textures of tree crown are very different from the other types. In this paper, we present an automatic method to detect tree crowns using high resolution image in urban environment without any apriori knowledge. Our method catches unique structure and texture of tree crown surface, use variance and mathematical expectation of defined image window to position the candidate canopy blocks coarsely, then analysis their inner structure and texture to refine these candidate blocks. The possible spans of all the feature parameters used in our method automatically generate from the small number of samples, and HOLE and its distribution as an important characteristics are introduced into refining processing. Also the isotropy of candidate image block and holes' distribution is integrated in our method. After introduction the theory of our method, aerial imageries were used ( with a resolution about 0.3m ) to test our method, and the results indicate that our method is an effective approach to automatically detect tree crown in urban environment.

Connecting people with ecosystems in the 21st century: an assessment of our nation's urban forests.

Treesearch

John F. Dwyer; David J. Nowak; Mary Heather Noble; Susan M. Sisinni

2000-01-01

Urban areas (cities, towns, villages, etc.) cover 3.5 percent of the 48 conterminous states and contain more than 75 percent of the population. urban areas, about 3.8 billion trees cover 27.1 percent of the land. On a broader scale, metropolitan areas (urban counties) cover 24.5 percent of the conterminous United States and contain 74.4 billion trees that cover 33.4...

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

Treesearch

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,...

Identification of the potential gap areas for the developing green infrastructure in the Urban area using High resolution satellite Imagery

NASA Astrophysics Data System (ADS)

Kanaparthi, M. B.

2017-12-01

In India urban population is growing day by day which is causing air pollution less air quality finally leading to climate change and global warming. To mitigate the effect of the climate change we need to plant more trees in the urban area. The objective of this study is develop a plan to improve the urban Green Infrastructure (GI) to fight against the climate change and global warming. Improving GI is a challenging and difficult task in the urban areas because land unavailability of land, to overcome the problem greenways is a good the solution. Greenway is a linear open space developed along the rivers, canals, roads in the urban areas to form a network of green spaces. Roads are the most common structures in the urban area. The idea is to develop the greenways alongside the road to connecting the different green spaces. Tree crowns will act as culverts to connect the green spaces. This will require the spatial structure of the green space, distribution of trees along the roads and the gap areas along the road where more trees can be planted. This can be achieved with help of high resolution Satellite Imagery and the object extraction techniques. This study was carried in the city Bhimavaram which is located in state Andhra Pradesh. The final outcome of this study is potential gap areas for planting trees in the city.

Spectral properties of plant leaves pertaining to urban landscape design of broad-spectrum solar ultraviolet radiation reduction

NASA Astrophysics Data System (ADS)

Yoshimura, Haruka; Zhu, Hui; Wu, Yunying; Ma, Ruijun

2010-03-01

Human exposure to harmful ultraviolet (UV) radiation has important public health implications. Actual human exposure to solar UV radiation depends on ambient UV irradiance, and the latter is influenced by ground reflection. In urban areas with higher reflectivity, UV exposure occurs routinely. To discover the solar UV radiation regulation mechanism of vegetation, the spectral reflectance and transmittance of plant leaves were measured with a spectrophotometer. Typically, higher plants have low leaf reflectance (around 5%) and essentially zero transmittance throughout the UV region regardless of plant species and seasonal change. Accordingly, incident UV radiation decreases to 5% by being reflected and is reduced to zero by passing through a leaf. Therefore, stratified structures of vegetation are working as another terminator of UV rays, protecting whole terrestrial ecosystems, while vegetation at waterfronts contributes to protect aquatic ecosystems. It is possible to protect the human population from harmful UV radiation by urban landscape design of tree shade and the botanical environment. Even thin but uniformly distributed canopy is effective in attenuating UV radiation. To intercept diffuse radiation, UV screening by vertical structures such as hedges should be considered. Reflectivity of vegetation is around 2%, as foliage surfaces reduce incident UV radiation via reflection, while also eliminating it by transmittance. Accordingly, vegetation reduces incident UV radiation to around 2% by reflection. Vegetation influence on ambient UV radiation is broad-spectrum throughout the UV region. Only trees provide cool UV protective shade. Urban landscapes aimed at abating urban heat islands integrated with a reduction of human UV over-exposure would contribute to mitigation of climate change.

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

Treesearch

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...

What's scale got to do with it? Models for urban tree canopy

Treesearch

Dexter H. Locke; Shawn M. Landry; Morgan Grove; Rinku Roy Chowdhury

2016-01-01

The uneven provisioning of ecosystem services has important policy implications; yet the spatial heterogeneity of tree canopy remains understudied. Private residential lands are important to the future of Philadelphia’s urban forest because a majority of the existing and possible tree canopy is located on residential land uses. This article examines the spatial...

An inventory of multipurpose avenue trees of urban Chandigarh, India

Treesearch

R. K. Kohli; H. P. Singh; Daizy R. Batish

2000-01-01

Trees in urban ecosystems play a very significant role in environmental protection by checking air and noise pollutants, abating wind, and handling many other functions, in India, Chandigarh is the most modern and environmentally safe city and qualifies to be called a GREEN CITY because of its rich tree component. This is so in spite of its high population density,...

Detectability of the emerald ash borer (Coleoptera: Buprestidae) in asymptomatic urban trees by using branch samples.

PubMed

Ryall, Krista L; Fidgen, Jeffrey G; Turgeon, Jean J

2011-06-01

The emerald ash borer, Agrilus planipennis Fairmaire, is an exotic invasive insect causing extensive mortality to ash trees, Fraxinus spp., in Canada and the United States. Detection of incipient populations of this pest is difficult because of its cryptic life stages and a multiyear time lag between initial attack and the appearance of signs or symptoms of infestation. We sampled branches from open-grown urban ash trees to develop a sample unit suitable for detecting low density A. planipennis infestation before any signs or symptoms are evident. The sample unit that maximized detection rates consisted of one 50-cm-long piece from the base of a branch ≥6 cm diameter in the midcrown. The optimal sample size was two such branches per tree. This sampling method detected ≈75% of asymptomatic trees known to be infested by using more intensive sampling and ≈3 times more trees than sampling one-fourth of the circumference of the trunk at breast height. The method is less conspicuous and esthetically damaging to a tree than the removal of bark from the main stem or the use of trap trees, and could be incorporated into routine sanitation or maintenance of city-owned trees to identify and delineate infested areas. This research indicates that branch sampling greatly reduces false negatives associated with visual surveys and window sampling at breast height. Detection of A. planipennis-infested asymptomatic trees through branch sampling in urban centers would provide landowners and urban foresters with more time to develop and implement management tactics.

Effect of controlled inoculation with specific mycorrhizal fungi from the urban environment on growth and physiology of containerized shade tree species growing under different water regimes.

PubMed

Fini, Alessio; Frangi, Piero; Amoroso, Gabriele; Piatti, Riccardo; Faoro, Marco; Bellasio, Chandra; Ferrini, Francesco

2011-11-01

The aim of this work was to evaluate the effects of selected mycorrhiza obtained in the urban environment on growth, leaf gas exchange, and drought tolerance of containerized plants growing in the nursery. Two-year-old uniform Acer campestre L., Tilia cordata Mill., and Quercus robur L. were inoculated with a mixture of infected roots and mycelium of selected arbuscular (maple, linden) and/or ectomycorrhiza (linden, oak) fungi and grown in well-watered or water shortage conditions. Plant biomass and leaf area were measured 1 and 2 years after inoculation. Leaf gas exchange, chlorophyll fluorescence, and water relations were measured during the first and second growing seasons after inoculation. Our data suggest that the mycelium-based inoculum used in this experiment was able to colonize the roots of the tree species growing in the nursery. Plant biomass was affected by water shortage, but not by inoculation. Leaf area was affected by water regime and, in oak and linden, by inoculation. Leaf gas exchange was affected by inoculation and water stress. V(cmax) and J(max) were increased by inoculation and decreased by water shortage in all species. F(v)/F(m) was also generally higher in inoculated plants than in control. Changes in PSII photochemistry and photosynthesis may be related to the capacity of inoculated plants to maintain less negative leaf water potential under drought conditions. The overall data suggest that inoculated plants were better able to maintain physiological activity during water stress in comparison to non-inoculated plants.

Identification of fine scale and landscape scale drivers of urban aboveground carbon stocks using high-resolution modeling and mapping.

PubMed

Mitchell, Matthew G E; Johansen, Kasper; Maron, Martine; McAlpine, Clive A; Wu, Dan; Rhodes, Jonathan R

2018-05-01

Urban areas are sources of land use change and CO 2 emissions that contribute to global climate change. Despite this, assessments of urban vegetation carbon stocks often fail to identify important landscape-scale drivers of variation in urban carbon, especially the potential effects of landscape structure variables at different spatial scales. We combined field measurements with Light Detection And Ranging (LiDAR) data to build high-resolution models of woody plant aboveground carbon across the urban portion of Brisbane, Australia, and then identified landscape scale drivers of these carbon stocks. First, we used LiDAR data to quantify the extent and vertical structure of vegetation across the city at high resolution (5×5m). Next, we paired this data with aboveground carbon measurements at 219 sites to create boosted regression tree models and map aboveground carbon across the city. We then used these maps to determine how spatial variation in land cover/land use and landscape structure affects these carbon stocks. Foliage densities above 5m height, tree canopy height, and the presence of ground openings had the strongest relationships with aboveground carbon. Using these fine-scale relationships, we estimate that 2.2±0.4 TgC are stored aboveground in the urban portion of Brisbane, with mean densities of 32.6±5.8MgCha -1 calculated across the entire urban land area, and 110.9±19.7MgCha -1 calculated within treed areas. Predicted carbon densities within treed areas showed strong positive relationships with the proportion of surrounding tree cover and how clumped that tree cover was at both 1km 2 and 1ha resolutions. Our models predict that even dense urban areas with low tree cover can have high carbon densities at fine scales. We conclude that actions and policies aimed at increasing urban carbon should focus on those areas where urban tree cover is most fragmented. Copyright © 2017 Elsevier B.V. All rights reserved.

Food availability and foraging near human developments by black bears

USGS Publications Warehouse

Merkle, Jerod A.; Robinson, Hugh S.; Krausman, Paul R.; Alaback, Paul B.

2013-01-01

Understanding the relationship between foraging ecology and the presence of human-dominated landscapes is important, particularly for American black bears (Ursus americanus), which sometimes move between wildlands and urban areas to forage. The food-related factors influencing this movement have not been explored, but can be important for understanding the benefits and costs to black bear foraging behavior and the fundamental origins of bear conflicts. We tested whether the scarcity of wildland foods or the availability of urban foods can explain when black bears forage near houses, examined the extent to which male bears use urban areas in comparison to females, and identified the most important food items influencing bear movement into urban areas. We monitored 16 collared black bears in and around Missoula, Montana, during 2009 and 2010, while quantifying the rate of change in green vegetation and the availability of 5 native berry-producing species outside the urban area, the rate of change in green vegetation, and the availability of apples and garbage inside the urban area. We used parametric time-to-event models in which an event was a bear location collected within 100 m of a house. We also visited feeding sites located near houses and quantified food items bears had eaten. The probability of a bear being located near a house was 1.6 times higher for males, and increased during apple season and the urban green-up. Fruit trees accounted for most of the forage items at urban feeding sites (49%), whereas wildland foods composed <10%. Black bears foraged on human foods near houses even when wildland foods were available, suggesting that the absence of wildland foods may not influence the probability of bears foraging near houses. Additionally, other attractants, in this case fruit trees, appear to be more important than the availability of garbage in influencing when bears forage near houses.

A method of detecting carbonyl compounds in tree leaves in China.

PubMed

Huang, Juan; Feng, Yanli; Fu, Jiamo; Sheng, Guoying

2010-06-01

Carbonyl compounds have been paid more and more attention because some carbonyl species have been proven to be carcinogenic or a risk for human health. Plant leaves are both an important emission source and an important sink of carbonyl compounds. But the research on carbonyl compounds from plant leaves is very scarce. In order to make an approach to the emission mechanism of plant leaves, a new method was established to extract carbonyl compounds from fresh plant leaves. The procedure combining derivatization with ultrasonication was developed for the fast extraction of carbonyl compounds from tree leaves. Fresh leaves (< 0.01 g) were minced and ultrasonicated in acidic 2,4-dinitrophenylhydrazine (DNPH)-acetonitrile solution for 30 min and then holding 30 min to allow aldehydes and ketones in leaves to react completely with DNPH. The extraction process was performed under room temperature and only took 60 min. The advantages of this method were very little sample preparation, requiring short treatment time and usual equipment. Four greening trees, i.e., camphor tree (Cinnamomum camphora), sweet olive (Osmanthus fragrans), cedar (Cedrus deodara), and dawn redwood (Metasequoia glyptostroboides), were selected and extracted by this method. Seven carbonyl compounds, including formaldehyde, acetaldehyde, acetone, acrolein, p-tolualdehyde, m/o-tolualdehyde, and hexaldehyde were determined and quantified. The most common carbonyl species of the four tree leaves were formaldehyde, acrolein, and m/o-tolualdehyde. They accounted for 67.3% in cedar, 50.8% in sweet olive, 45.8% in dawn redwood, and 44.6% in camphor tree, respectively. Camphor tree had the highest leaf level of m/o-tolualdehyde with 15.0 +/- 3.4 microg g(-1)(fresh leaf weight), which indicated that camphor tree may be a bioindicator of the level of tolualdehyde or xylene in the atmosphere. By analyzing carbonyl compounds from different tree leaves, it is not only helpful for further studying the relationship between sink and emission of carbonyls from plants, but also helpful for exploring optimum plant population in urban greening.

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

NASA Astrophysics Data System (ADS)

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.

Ecosystem services from converted land: the importance of tree cover in Amazonian pastures

USGS Publications Warehouse

Barrett, Kirsten; Valentim, Judson; Turner, B. L.

2013-01-01

Deforestation is responsible for a substantial fraction of global carbon emissions and changes in surface energy budgets that affect climate. Deforestation losses include wildlife and human habitat, and myriad forest products on which rural and urban societies depend for food, fiber, fuel, fresh water, medicine, and recreation. Ecosystem services gained in the transition from forests to pasture and croplands, however, are often ignored in assessments of the impact of land cover change. The role of converted lands in tropical areas in terms of carbon uptake and storage is largely unknown. Pastures represent the fastest-growing form of converted land use in the tropics, even in some areas of rapid urban expansion. Tree biomass stored in these areas spans a broad range, depending on tree cover. Trees in pasture increase carbon storage, provide shade for cattle, and increase productivity of forage material. As a result, increasing fractional tree cover can provide benefits land managers as well as important ecosystem services such as reducing conversion pressure on forests adjacent to pastures. This study presents an estimation of fractional tree cover in pasture in a dynamic region on the verge of large-scale land use change. An appropriate sampling interval is established for similar studies, one that balances the need for independent samples of sufficient number to characterize a pasture in terms of fractional tree cover. This information represents a useful policy tool for government organizations and NGOs interested in encouraging ecosystem services on converted lands. Using high spatial resolution remotely sensed imagery, fractional tree cover in pasture is quantified for the municipality of Rio Branco, Brazil. A semivariogram and devolving spatial resolution are employed to determine the coarsest sampling interval that may be used, minimizing effects of spatial autocorrelation. The coarsest sampling interval that minimizes spatial dependence was about 22 m. The area-weighted fractional tree cover for the study area was 1.85 %, corrected for a slight bias associated with the coarser sampling resolution. The pastures sampled for fractional tree cover were divided between ‘high’ and ‘low’ tree cover, which may be the result of intentional incorporation of arboreal species in pasture. Further research involving those ranchers that have a higher fractional tree cover may indicate ways to promote the practice on a broader scale in the region.

Estimating urban forest carbon sequestration potential in the southern United States using current remote sensing imagery sources

Treesearch

Krista Merry; Pete Bettinger; Jacek Siry; J. Michael Bowker

2015-01-01

With an increased interest in reducing carbon dioxide in the atmosphere, tree planting and maintenance in urban areas has become a viable option for increasing carbon sequestration. Methods for assessing the potential for planting trees within an urban area should allow for quick, inexpensive, and accurate estimations of available land using current remote sensing...

UFORE (i-Tree Eco) Analysis of Chicago

Treesearch

Cherie LeBlanc Fisher; David Nowak

2010-01-01

The USDA Forest Service and City of Chicago conducted a UFORE (now called i-Tree Eco) analysis of Chicago's urban forest in the summer of 2007. The UFORE (Urban FORest Effects) model developed by the Forest Service uses on-the-ground sampling data to understand the composition of on urban forest and calculate the forest's impacts on air pollution and energy...

Effect of plot and sample size on timing and precision of urban forest assessments

Treesearch

David J. Nowak; Jeffrey T. Walton; Jack C. Stevens; Daniel E. Crane; Robert E. Hoehn

2008-01-01

Accurate field data can be used to assess ecosystem services from trees and to improve urban forest management, yet little is known about the optimization of field data collection in the urban environment. Various field and Geographic Information System (GIS) tests were performed to help understand how time costs and precision of tree population estimates change with...

The potential of urban tree plantings to be cost effective in carbon credit markets

Treesearch

M.R. McHale; E.G. McPherson; I.C. Burke

2007-01-01

Emission trading is considered to be an economically sensitive method for reducing the concentrations of greenhouse gases, particularly carbon dioxide, in the atmosphere. There has been debate about the viability of using urban tree plantings in these markets. The main concern is whether or not urban planting projects can be cost effective options for investors. We...

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

Treesearch

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,...

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

Treesearch

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...

Orchards for edible cities: cadmium and lead content in nuts, berries, pome and stone fruits harvested within the inner city neighbourhoods in Berlin, Germany.

PubMed

von Hoffen, Laura Pauline; Säumel, Ina

2014-03-01

Today's urban gardening focuses mainly on vegetable production and rarely includes fruit trees. Health effects of consuming urban crops are questioned due to high local pollution loads. Here, we determined cadmium and lead content in the edible parts of nuts, berries, pome, and stone fruits harvested from fruit trees and shrubs within inner city neighbourhoods of Berlin, Germany. We analysed how local settings at sampling sites shaped the trace metal content. We revealed significant differences in trace metal content depending on species, fruit type, local traffic, and parameters related to barriers between the sampling site and neighbouring roads. Higher overall traffic burden and proximity to roads increased whereas buildings or vegetation as barriers reduced trace metal content in the edible biomass. We demonstrate, that the consumption of non-vegetable fruits growing in inner city sites in Berlin does not pose a risk on human health as long as the fruits are thoroughly washed and it is provided that site pollutions and impacts are considered in garden concepts and guidelines. © 2013 Published by Elsevier Inc.

Monitoring of the environmental pollution by trace element analysis in tree-rings using synchrotron radiation total reflection X-ray fluorescence

NASA Astrophysics Data System (ADS)

de Vives, Ana Elisa Sirito; Moreira, Silvana; Brienza, Sandra Maria Boscolo; Medeiros, Jean Gabriel Silva; Filho, Mário Tomazello; Zucchi, Orghêda Luíza Araújo Domingues; Filho, Virgílio Franco do Nascimento

2006-11-01

This paper aims to study the environmental pollution in the tree development, in order to evaluate its use as bioindicator in urban and country sides. The sample collection was carried out in Piracicaba city, São Paulo State, which presents high level of environmental contamination in water, soil and air, due to industrial activities, vehicles combustion, sugar-cane leaves burning in the harvesting, etc. The species Caesalpinia peltophoroides ("Sibipiruna") was selected because it is widely used in urban forestation. Synchrotron Radiation Total Reflection X-ray Fluorescence technique (SR-TXRF) was employed to identify and quantify the elements and metals of nutritional and toxicological importance in the wood samples. The analysis was performed in the Brazilian Synchrotron Light Source Laboratory, using a white beam for excitation and a Si(Li) detector for X-ray detection. In several samples, P, K, Ca, Ti, Fe, Sr, Ba and Pb were quantified. The K/Ca, K/P and Pb/Ca ratios were found to decrease towards the bark.

Development of multi-functional streetscape green infrastructure using a performance index approach.

PubMed

Tiwary, A; Williams, I D; Heidrich, O; Namdeo, A; Bandaru, V; Calfapietra, C

2016-01-01

This paper presents a performance evaluation framework for streetscape vegetation. A performance index (PI) is conceived using the following seven traits, specific to the street environments - Pollution Flux Potential (PFP), Carbon Sequestration Potential (CSP), Thermal Comfort Potential (TCP), Noise Attenuation Potential (NAP), Biomass Energy Potential (BEP), Environmental Stress Tolerance (EST) and Crown Projection Factor (CPF). Its application is demonstrated through a case study using fifteen street vegetation species from the UK, utilising a combination of direct field measurements and inventoried literature data. Our results indicate greater preference to small-to-medium size trees and evergreen shrubs over larger trees for streetscaping. The proposed PI approach can be potentially applied two-fold: one, for evaluation of the performance of the existing street vegetation, facilitating the prospects for further improving them through management strategies and better species selection; two, for planning new streetscapes and multi-functional biomass as part of extending the green urban infrastructure. Copyright © 2015 Elsevier Ltd. All rights reserved.

Nested PCR detection and phylogenetic analysis of Babesia bovis and Babesia bigemina in cattle from Peri-urban localities in Gauteng Province, South Africa.

PubMed

Mtshali, Phillip Senzo; Tsotetsi, Ana Mbokeleng; Thekisoe, Matlhahane Molifi Oriel; Mtshali, Moses Sibusiso

2014-01-01

Babesia bovis and Babesia bigemina are tick-borne hemoparasites causing babesiosis in cattle worldwide. This study was aimed at providing information about the occurrence and geographical distribution of B. bovis and B. bigemina species in cattle from Gauteng province, South Africa. A total of 268 blood samples collected from apparently healthy animals in 14 different peri-urban localities were tested using previously established nested PCR assays for the detection of B. bovis and B. bigemina species-specific genes encoding rhoptry-associated protein 1 (RAP-1) and SpeI-AvaI restriction fragment, respectively. Nested PCR assays revealed that the overall prevalence was 35.5% (95% confidence interval [CI]=± 5.73) and 76.1% (95% CI=± 5.11) for B. bovis and B. bigemina, respectively. PCR results were corroborated by sequencing amplicons of randomly selected samples. The neighbor-joining trees were constructed to study the phylogenetic relationship between B. bovis and B. bigemina sequences of randomly selected isolates. Analysis of phylogram inferred with B. bovis RAP-1 sequences indicated a close relationship between our isolates and GenBank strains. On the other hand, a tree constructed with B. bigemina gp45 sequences revealed a high degree of polymorphism among the B. bigemina isolates investigated in this study. Taken together, the results presented in this work indicate the high incidence of Babesia parasites in cattle from previously uncharacterised peri-urban areas of the Gauteng province. These findings suggest that effective preventative and control measures are essential to curtail the spread of Babesia infections among cattle populations in Gauteng.

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

Treesearch

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...

Implementing municipal tree planting: Los Angeles million tree initiative

Treesearch

S. Pincetl

2010-01-01

Urban forests are increasingly being seen as an important infrastructure that can help cities remediate their environmental impacts. This work reports on the first steps in implementing a million tree program in Los Angeles and the ways such a biogenic—living—infrastructure has been approached. Numbers of studies have been done to quantify the benefits of urban forests...

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

NASA Astrophysics Data System (ADS)

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, should also be considered when building these records.

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

PubMed

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 (<13.2%) in the neighborhood-averaged 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.

The ecological impact of city lighting scenarios: exploring gap crossing thresholds for urban bats.

PubMed

Hale, James D; Fairbrass, Alison J; Matthews, Thomas J; Davies, Gemma; Sadler, Jon P

2015-02-02

As the global population urbanizes, dramatic changes are expected in city lighting and the urban form, which may threaten the functioning of urban ecosystems and the services they deliver. However, little is known about the ecological impact of lighting in different urban contexts. Movement is an important ecological process that can be disrupted by artificial lighting. We explored the impact of lighting on gap crossing for Pipistrellus pipistrellus, a species of bat (Chiroptera) common within UK cities. We aimed to determine whether the probability of crossing gaps in tree cover varied with crossing distance and lighting level, through stratified field surveys. We then used the resulting data on barrier thresholds to model the landscape resistance due to lighting across an entire city and explored the potential impact of scenarios for future changes to street lighting. The level of illumination required to create a barrier effect reduced as crossing distance increased. For those gaps where crossing was recorded, bats selected the darker parts of gaps. Heavily built parts of the case study city were associated with large and brightly lit gaps, and spatial models indicate movement would be highly restricted in these areas. Under a scenario for brighter street lighting, the area of accessible land cover was further reduced in heavily built parts of the city. We believe that this is the first study to demonstrate how lighting may create resistance to species movement throughout an entire city. That connectivity in urban areas is being disrupted for a relatively common species raises questions about the impacts on less tolerant groups and the resilience of bat communities in urban centres. However, this mechanistic approach raises the possibility that some ecological function could be restored in these areas through the strategic dimming of lighting and narrowing of gaps. © 2015 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.

Evidence for Near-Road Air Pollution Abatement by Tree Cover

EPA Science Inventory

Urbanized areas represent concentrated demand for ecosystem services to buffer hazards and promote healthful lifestyles. Urban tree cover has been linked to multiple local health benefits including clean air and water, flood and drought protection, heat mitigation, and opportuni...

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

NASA Astrophysics Data System (ADS)

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.

[Competition among dominant tree species in a natural spruce-fir forest in Changbai Mountain].

PubMed

Ren, Mei Mei; Yang, Hua

2016-10-01

Dominant tree species are the main species in different layers of mixed-species forests. Examining competitive relationships among dominant tree species is important for proper management of mixedwood forests. In this study, we established a 100 m×100 m plot of uniform condition on Jingouling Forest Farm, Wangqing County, Jilin Province. The dominant tree species of the young forest community were first determined through dominance index analysis approach and the competitive relationships among dominant tree species were then examined using tree competition index that described intra- and inter-specific competition from the above and sides of individual tree crown. The results indicated three dominant tree species in this mixed-species community were Abies nephrolepis, Picea koraiensis and Pinus koraiensis. A. nephrolepis, Picea koraiensis, Pinus koraiensis, Betula costata, Tilia amurensis, Acer tegmentosum and Betula platyphylla were the main competitors of the dominant tree species, while A. nephrolepis was the major competitor for all three dominant tree species (1412.48), followed by Picea koraiensis (439.17) and Pinus koraiensis (245.28), they all had side squeeze effect (64.9%, 65.2% and 66.0% of the total competition for the three dominant tree species, respectively). The level of side and above competition decreased with individual tree DBH (diameter at breast height); the percentage of side competition was nearly equal to that of above competition in small trees and increased with tree size, reaching nearly 100% in large canopy trees. For the three dominant tree species, the side and above competition of three dominant tree species mainly came from A. nephrolepis, Picea koraiensis, Pinus koraiensis, T. amurensis, B. costata, A. tegmentosum and B. platyphylla, and the inter-specific competition was more intense than intra-specific competition (58.4%, 87.1%, 83.7% of the total competition for the three dominant species), both of which decreased with the increase of individual tree DBH.

Intra-Urban Variability in Elemental Carbon Deposition to Tree Canopies

NASA Astrophysics Data System (ADS)

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

2017-12-01

Urban areas cover <1% of the earth's land surface, yet they represent globally significant sources of atmospheric elemental carbon (EC). A product of incomplete fossil fuel, biofuel, and 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) and far from roads (>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.

The Inference of Gene Trees with Species Trees

PubMed Central

Szöllősi, Gergely J.; Tannier, Eric; Daubin, Vincent; Boussau, Bastien

2015-01-01

This article reviews the various models that have been used to describe the relationships between gene trees and species trees. Molecular phylogeny has focused mainly on improving models for the reconstruction of gene trees based on sequence alignments. Yet, most phylogeneticists seek to reveal the history of species. Although the histories of genes and species are tightly linked, they are seldom identical, because genes duplicate, are lost or horizontally transferred, and because alleles can coexist in populations for periods that may span several speciation events. Building models describing the relationship between gene and species trees can thus improve the reconstruction of gene trees when a species tree is known, and vice versa. Several approaches have been proposed to solve the problem in one direction or the other, but in general neither gene trees nor species trees are known. Only a few studies have attempted to jointly infer gene trees and species trees. These models account for gene duplication and loss, transfer or incomplete lineage sorting. Some of them consider several types of events together, but none exists currently that considers the full repertoire of processes that generate gene trees along the species tree. Simulations as well as empirical studies on genomic data show that combining gene tree–species tree models with models of sequence evolution improves gene tree reconstruction. In turn, these better gene trees provide a more reliable basis for studying genome evolution or reconstructing ancestral chromosomes and ancestral gene sequences. We predict that gene tree–species tree methods that can deal with genomic data sets will be instrumental to advancing our understanding of genomic evolution. PMID:25070970

Bird population and habitat surveys in urban areas

USGS Publications Warehouse

DeGraaf, R.M.; Geis, A.D.; Healy, P.A.

1991-01-01

Breeding bird populations in six habitats in Columbia. MD, were studied to develop procedures suitable for measuring bird use of residential areas and to identify habitat characteristics that define the distribution of various common bird species. A procedure to measure bird use based on 4-min transect counts on plots measuring 91 m ? 91 m proved better than point counts. Transect counts reduced many of the problems associated with counting birds in urban areas, such as varying noise and visibility. Eighty percent of observations were recorded in the first 4 min. Habitat measurement procedures were examined also. It was found that a subsample of woody tree and shrub crown volumes made on 0.2 ha was highly correlated with similar measures made on 0.8-ha plots.

Evaluation of thermal perception in schoolyards under Mediterranean climate conditions

NASA Astrophysics Data System (ADS)

Antoniadis, D.; Katsoulas, N.; Papanastasiou, D.; Christidou, V.; Kittas, C.

2016-03-01

The aim of this paper was to study qualitatively and quantitatively the thermal perception and corresponding heat stress conditions that prevail in two schoolyards in a coastal city in central Greece. For this purpose, meteorological parameters (i.e., wind speed, temperature, relative humidity, solar radiation) were recorded at 70 and 55 measuring points in the schoolyards, from 14:00 to 15:30 local time, during May and June of 2011. The measuring points were distributed so as to get measurements at points (a) directly exposed to the sun, (b) under the shadow of trees and building structures, and (c) near building structures. Cluster analysis was applied to group observations and revealed places that are microclimatically homogeneous. Thermal perception and heat stress conditions were assessed by means of the physiologically equivalent temperature (PET, °C), and the results are presented in relevant charts. The impact of material's albedo, radiation's reflection by structures and obstacles, and different tree species on thermal perception and heat stress conditions was also assessed. The analysis showed that trees triggered a reduction of incident solar radiation that ranged between 79 and 94 % depending on tree's species, crown dimension, tree height, and leaf area. PET values were mainly affected by solar radiation and wind speed. Trees caused a reduction of up to 37 % in PET values, while a 1-m s-1 increase in wind speed triggered a reduction of 3.7-5.0 °C in PET value. The effective shading area in the two schoolyards was small, being 27.5 and 11 %. The results of this study could be exploited by urban planning managers when designing or improving the outdoor environment of a school complex.

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

PubMed

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

2016-01-01

A crucial issue in urban environments is the interaction between urban trees and atmospheric pollution, particularly ozone (O). 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 O emissions, there is growing scientific activity aimed at understanding O removal by vegetation, particularly trees. The intent of this paper is to provide the state of the art and suggestions to improve future studies of O fluxes and to discuss implications of O flux studies to maximize environmental services through the planning and management of urban forests. To evaluate and quantify the potential of O removal in urban and peri-urban forests, we describe experimental approaches to measure O fluxes, distinguishing laboratory experiments, field measurements, and model estimates, including recent case studies. We discuss the strengths and weaknesses of the different approaches and conclude that the combination of the three levels of investigation is essential for estimating O removal by urban trees. We also comment on the implications of these findings for planning and management of urban forests, suggesting some key issues that should be considered to maximize O removal by urban and peri-urban forests. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Comparative assessment of methods for estimating tree canopy cover across a rural-to-urban gradient in the mid-Atlantic region of the USA

Treesearch

Rachel Riemann; Greg C. Liknes; Jarlath O' Neil-Dunne; Chris Toney; Tonya Lister

2016-01-01

Tree canopy cover significantly affects human and wildlife habitats, local hydrology, carbon cycles, fire behavior, and ecosystem services of all types. In addition, changes in tree canopy cover are both indicators and consequences of a wide variety of disturbances from urban development to climate change. There is growing demand for this information nationwide and...

Multiple health benefits of urban tree canopy: The mounting evidence for a green prescription

Treesearch

Jared M. Ulmer; Kathleen L. Wolf; Desiree R. Backman; Raymond L. Tretheway; Cynthia JA Blain; Jarlath PM O’Neil-Dunne; Lawrence D. Frank

2016-01-01

The purpose of this study was to enhance the understanding of the health-promoting potential of trees in an urbanized region of the United States. This was done using high-resolution LiDAR and imagery data to quantify tree cover within 250 m of the residence of 7910 adult participants in the California Health Interview Survey, then testing for main and mediating...

Planting forests in NYC: Is the goal restoration, reforestation, or afforestation?

Treesearch

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...

National Forest Health Monitoring Program Wisconsin Street Tree Assessment 2002-2003, NA-FR-02-08

Treesearch

Anne Cumming; Daniel Twardus; Robert Hoehn; David Nowak; Manfred Mielke; Richard Rideout; Helen Butalla; Patricia Lebow

2008-01-01

Street trees grow along roadways within the public right-of-way. They are an important part of the urban forest due to their visibility to motorists and pedestrians, even if their numbers represent a small fraction of trees in urban areas. Little data are available that describe this resource at a large, statewide scale. In 2000, the Forest Service, U.S....

Strategic tree planting as an EPA encouraged pollutant reduction strategy: how urban trees can obtain credit in state implementation plans

Treesearch

Dr. David J. Nowak

2005-01-01

As tree programs are new to the SIP process, "to facilitate Federal approval of an emerging or voluntary measure States are encouraged to work with their EPA regional ofice during the development process". Programs to increase canopy cover in urban areas can achieve many benefits. They can help improve air and water quality, as well as other factors related...

A multiplex PCR-based method for the detection and early identification of wood rotting fungi in standing trees.

PubMed

Guglielmo, F; Bergemann, S E; Gonthier, P; Nicolotti, G; Garbelotto, M

2007-11-01

The goal of this research was the development of a PCR-based assay to identify important decay fungi from wood of hardwood tree species in northern temperate regions. Eleven taxon-specific primers were designed for PCR amplification of either nuclear or mitochondrial ribosomal DNA regions of Armillaria spp., Ganoderma spp., Hericium spp., Hypoxylon thouarsianum var. thouarsianum, Inonotus/Phellinus-group, Laetiporus spp., Perenniporia fraxinea, Pleurotus spp., Schizophyllum spp., Stereum spp. and Trametes spp. Multiplex PCR reactions were developed and optimized to detect fungal DNA and identify each taxon with a sensitivity of at least 1 pg of target DNA in the template. This assay correctly identified the agents of decay in 82% of tested wood samples. The development and optimization of multiplex PCRs allowed for reliable identification of wood rotting fungi directly from wood. Early detection of wood decay fungi is crucial for assessment of tree stability in urban landscapes. Furthermore, this method may prove useful for prediction of the severity and the evolution of decay in standing trees.

The influence of the interactions between anthropogenic activities and multiple ecological factors on land surface temperatures of urban forests

NASA Astrophysics Data System (ADS)

Ren, Y.

2017-12-01

Context Land surface temperatures (LSTs) spatio-temporal distribution pattern of urban forests are influenced by many ecological factors; the identification of interaction between these factors can improve simulations and predictions of spatial patterns of urban cold islands. This quantitative research requires an integrated method that combines multiple sources data with spatial statistical analysis. Objectives The purpose of this study was to clarify urban forest LST influence interaction between anthropogenic activities and multiple ecological factors using cluster analysis of hot and cold spots and Geogdetector model. We introduced the hypothesis that anthropogenic activity interacts with certain ecological factors, and their combination influences urban forests LST. We also assumed that spatio-temporal distributions of urban forest LST should be similar to those of ecological factors and can be represented quantitatively. Methods We used Jinjiang as a representative city in China as a case study. Population density was employed to represent anthropogenic activity. We built up a multi-source data (forest inventory, digital elevation models (DEM), population, and remote sensing imagery) on a unified urban scale to support urban forest LST influence interaction research. Through a combination of spatial statistical analysis results, multi-source spatial data, and Geogdetector model, the interaction mechanisms of urban forest LST were revealed. Results Although different ecological factors have different influences on forest LST, in two periods with different hot spots and cold spots, the patch area and dominant tree species were the main factors contributing to LST clustering in urban forests. The interaction between anthropogenic activity and multiple ecological factors increased LST in urban forest stands, linearly and nonlinearly. Strong interactions between elevation and dominant species were generally observed and were prevalent in either hot or cold spots areas in different years. Conclusions In conclusion, a combination of spatial statistics and GeogDetector models should be effective for quantitatively evaluating interactive relationships among ecological factors, anthropogenic activity and LST.

Specific Detection and Identification of American Mulberry-Infecting and Italian Olive-Associated Strains of Xylella fastidiosa by Polymerase Chain Reaction

PubMed Central

Guan, Wei; Shao, Jonathan; Elbeaino, Toufic; Davis, Robert E.; Zhao, Tingchang; Huang, Qi

2015-01-01

Xylella fastidiosa causes bacterial leaf scorch in many landscape trees including elm, oak, sycamore and mulberry, but methods for specific identification of a particular tree host species-limited strain or differentiation of tree-specific strains are lacking. It is also unknown whether a particular landscape tree-infecting X. fastidiosa strain is capable of infecting multiple landscape tree species in an urban environment. We developed two PCR primers specific for mulberry-infecting strains of X. fastidiosa based on the nucleotide sequence of a unique open reading frame identified only in mulberry-infecting strains among all the North and South American strains of X. fastidiosa sequenced to date. PCR using the primers allowed for detection and identification of mulberry-infecting X. fastidiosa strains in cultures and in samples collected from naturally infected mulberry trees. In addition, no mixed infections with or non-specific detections of the mulberry-infecting strains of X. fastidiosa were found in naturally X. fastidiosa-infected oak, elm and sycamore trees growing in the same region where naturally infected mulberry trees were grown. This genotype-specific PCR assay will be valuable for disease diagnosis, studies of strain-specific infections in insects and plant hosts, and management of diseases caused by X. fastidiosa. Unexpectedly but interestingly, the unique open reading frame conserved in the mulberry-infecting strains in the U. S. was also identified in the recently sequenced olive-associated strain CoDiRO isolated in Italy. When the primer set was tested against naturally infected olive plant samples collected in Italy, it allowed for detection of olive-associated strains of X. fastidiosa in Italy. This PCR assay, therefore, will also be useful for detection and identification of the Italian group of X. fastidiosa strains to aid understanding of the occurrence, evolution and biology of this new group of X. fastidiosa strains. PMID:26061051

Specific Detection and Identification of American Mulberry-Infecting and Italian Olive-Associated Strains of Xylella fastidiosa by Polymerase Chain Reaction.

PubMed

Guan, Wei; Shao, Jonathan; Elbeaino, Toufic; Davis, Robert E; Zhao, Tingchang; Huang, Qi

2015-01-01

Xylella fastidiosa causes bacterial leaf scorch in many landscape trees including elm, oak, sycamore and mulberry, but methods for specific identification of a particular tree host species-limited strain or differentiation of tree-specific strains are lacking. It is also unknown whether a particular landscape tree-infecting X. fastidiosa strain is capable of infecting multiple landscape tree species in an urban environment. We developed two PCR primers specific for mulberry-infecting strains of X. fastidiosa based on the nucleotide sequence of a unique open reading frame identified only in mulberry-infecting strains among all the North and South American strains of X. fastidiosa sequenced to date. PCR using the primers allowed for detection and identification of mulberry-infecting X. fastidiosa strains in cultures and in samples collected from naturally infected mulberry trees. In addition, no mixed infections with or non-specific detections of the mulberry-infecting strains of X. fastidiosa were found in naturally X. fastidiosa-infected oak, elm and sycamore trees growing in the same region where naturally infected mulberry trees were grown. This genotype-specific PCR assay will be valuable for disease diagnosis, studies of strain-specific infections in insects and plant hosts, and management of diseases caused by X. fastidiosa. Unexpectedly but interestingly, the unique open reading frame conserved in the mulberry-infecting strains in the U. S. was also identified in the recently sequenced olive-associated strain CoDiRO isolated in Italy. When the primer set was tested against naturally infected olive plant samples collected in Italy, it allowed for detection of olive-associated strains of X. fastidiosa in Italy. This PCR assay, therefore, will also be useful for detection and identification of the Italian group of X. fastidiosa strains to aid understanding of the occurrence, evolution and biology of this new group of X. fastidiosa strains.

Does Gene Tree Discordance Explain the Mismatch between Macroevolutionary Models and Empirical Patterns of Tree Shape and Branching Times?

PubMed Central

Stadler, Tanja; Degnan, James H.; Rosenberg, Noah A.

2016-01-01

Classic null models for speciation and extinction give rise to phylogenies that differ in distribution from empirical phylogenies. In particular, empirical phylogenies are less balanced and have branching times closer to the root compared to phylogenies predicted by common null models. This difference might be due to null models of the speciation and extinction process being too simplistic, or due to the empirical datasets not being representative of random phylogenies. A third possibility arises because phylogenetic reconstruction methods often infer gene trees rather than species trees, producing an incongruity between models that predict species tree patterns and empirical analyses that consider gene trees. We investigate the extent to which the difference between gene trees and species trees under a combined birth–death and multispecies coalescent model can explain the difference in empirical trees and birth–death species trees. We simulate gene trees embedded in simulated species trees and investigate their difference with respect to tree balance and branching times. We observe that the gene trees are less balanced and typically have branching times closer to the root than the species trees. Empirical trees from TreeBase are also less balanced than our simulated species trees, and model gene trees can explain an imbalance increase of up to 8% compared to species trees. However, we see a much larger imbalance increase in empirical trees, about 100%, meaning that additional features must also be causing imbalance in empirical trees. This simulation study highlights the necessity of revisiting the assumptions made in phylogenetic analyses, as these assumptions, such as equating the gene tree with the species tree, might lead to a biased conclusion. PMID:26968785

Tree Species Richness Promotes Invertebrate Herbivory on Congeneric Native and Exotic Tree Saplings in a Young Diversity Experiment.

PubMed

Wein, Annika; Bauhus, Jürgen; Bilodeau-Gauthier, Simon; Scherer-Lorenzen, Michael; Nock, Charles; Staab, Michael

2016-01-01

Tree diversity in forests is an important driver of ecological processes including herbivory. Empirical evidence suggests both negative and positive effects of tree diversity on herbivory, which can be, respectively, attributed to associational resistance or associational susceptibility. Tree diversity experiments allow testing for associational effects, but evidence regarding which pattern predominates is mixed. Furthermore, it is unknown if herbivory on tree species of native vs. exotic origin is influenced by changing tree diversity in a similar way, or if exotic tree species escape natural enemies, resulting in lower damage that is unrelated to tree diversity. To address these questions, we established a young tree diversity experiment in temperate southwestern Germany that uses high planting density (49 trees per plot; plot size 13 m2). The species pool consists of six congeneric species pairs of European and North American origin (12 species in total) planted in monocultures and mixtures (1, 2, 4, 6 species). We assessed leaf damage by leaf-chewing insects on more than 5,000 saplings of six broadleaved tree species. Plot-level tree species richness increased leaf damage, which more than doubled from monocultures to six-species mixtures, strongly supporting associational susceptibility. However, leaf damage among congeneric native and exotic species pairs was similar. There were marked differences in patterns of leaf damage across tree genera, and only the genera likely having a predominately generalist herbivore community showed associational susceptibility, irrespective of the geographical origin of a tree species. In conclusion, an increase in tree species richness in young temperate forests may result in associational susceptibility to feeding by generalist herbivores.

Cost-Benefit Analysis for Biological Control Programs That Targeted Insect Pests of Eucalypts in Urban Landscapes of California.

PubMed

Paine, T D; Millar, J G; Hanks, L M; Gould, J; Wang, Q; Daane, K; Dahlsten, D L; Mcpherson, E G

2015-12-01

As well as being planted for wind breaks, landscape trees, and fuel wood, eucalypts are also widely used as urban street trees in California. They now are besieged by exotic insect herbivores of four different feeding guilds. The objective of the current analysis was to determine the return on investment from biological control programs that have targeted these pests. Independent estimates of the total number of eucalypt street trees in California ranged from a high of 476,527 trees (based on tree inventories from 135 California cities) to a low of 190,666 trees (based on 49 tree inventories). Based on a survey of 3,512 trees, the estimated mean value of an individual eucalypt was US$5,978. Thus, the total value of eucalypt street trees in California ranged from more than US$1.0 billion to more than US$2.8 billion. Biological control programs that targeted pests of eucalypts in California have cost US$2,663,097 in extramural grants and University of California salaries. Consequently, the return derived from protecting the value of this resource through the biological control efforts, per dollar expended, ranged from US$1,070 for the high estimated number of trees to US$428 for the lower estimate. The analyses demonstrate both the tremendous value of urban street trees, and the benefits that stem from successful biological control programs aimed at preserving these trees. Economic analyses such as this, which demonstrate the substantial rates of return from successful biological control of invasive pests, may play a key role in developing both grass-roots and governmental support for future urban biological control efforts. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

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

PubMed

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 proactive, ecosystem services approach to urban forest management. Copyright © 2017. Published by Elsevier Inc.

Floodplain forest loss and changes in forest community composition and structure in the upper Mississippi River: a wildlife habitat at risk

USGS Publications Warehouse

Knutson, M.G.; Klaas, E.E.

1998-01-01

Large floodplain forests represent a threatened and endangered type of ecosystem in the United States. Estimates of cumulative losses of floodplain forest range from 57% to 95% at different locations within the continental United Stales. Floodplain forests of the Upper Mississippi River (UMR) have significantly declined in extent due to agriculture, lock and dam construction, and urban development since European settlement. We collected data on shrubs, herbs, and trees from 56 floodplain forest plots in 1992 and compared our results with a previous analysis of historical tree data from the same area recorded by the General Land Office Survey in the 1840s. Acer saccharinum strongly dominates among mature trees and its relative dominance has increased over time. Salix spp. And Betula nigra have declined in relative dominance. Tree sizes are similar to those of presettlement forests, but present forests have fewer trees. The lack of early successional tree species and a trend toward an increasing monoculture of A. Saccharinum in the mature stages indicate problems with regeneration. Because floodplain forests represent a rare habitat type, losses and changes in habitat quality could pose serious problems for wildlife that depend upon these habitats, especially birds.

An estimate of the number of tropical tree species.

PubMed

Slik, J W Ferry; Arroyo-Rodríguez, Víctor; Aiba, Shin-Ichiro; Alvarez-Loayza, Patricia; Alves, Luciana F; Ashton, Peter; Balvanera, Patricia; Bastian, Meredith L; Bellingham, Peter J; van den Berg, Eduardo; Bernacci, Luis; da Conceição Bispo, Polyanna; Blanc, Lilian; Böhning-Gaese, Katrin; Boeckx, Pascal; Bongers, Frans; Boyle, Brad; Bradford, Matt; Brearley, Francis Q; Breuer-Ndoundou Hockemba, Mireille; Bunyavejchewin, Sarayudh; Calderado Leal Matos, Darley; Castillo-Santiago, Miguel; Catharino, Eduardo L M; Chai, Shauna-Lee; Chen, Yukai; Colwell, Robert K; Chazdon, Robin L; Robin, Chazdon L; Clark, Connie; Clark, David B; Clark, Deborah A; Culmsee, Heike; Damas, Kipiro; Dattaraja, Handanakere S; Dauby, Gilles; Davidar, Priya; DeWalt, Saara J; Doucet, Jean-Louis; Duque, Alvaro; Durigan, Giselda; Eichhorn, Karl A O; Eisenlohr, Pedro V; Eler, Eduardo; Ewango, Corneille; Farwig, Nina; Feeley, Kenneth J; Ferreira, Leandro; Field, Richard; de Oliveira Filho, Ary T; Fletcher, Christine; Forshed, Olle; Franco, Geraldo; Fredriksson, Gabriella; Gillespie, Thomas; Gillet, Jean-François; Amarnath, Giriraj; Griffith, Daniel M; Grogan, James; Gunatilleke, Nimal; Harris, David; Harrison, Rhett; Hector, Andy; Homeier, Jürgen; Imai, Nobuo; Itoh, Akira; Jansen, Patrick A; Joly, Carlos A; de Jong, Bernardus H J; Kartawinata, Kuswata; Kearsley, Elizabeth; Kelly, Daniel L; Kenfack, David; Kessler, Michael; Kitayama, Kanehiro; Kooyman, Robert; Larney, Eileen; Laumonier, Yves; Laurance, Susan; Laurance, William F; Lawes, Michael J; Amaral, Ieda Leao do; Letcher, Susan G; Lindsell, Jeremy; Lu, Xinghui; Mansor, Asyraf; Marjokorpi, Antti; Martin, Emanuel H; Meilby, Henrik; Melo, Felipe P L; Metcalfe, Daniel J; Medjibe, Vincent P; Metzger, Jean Paul; Millet, Jerome; Mohandass, D; Montero, Juan C; de Morisson Valeriano, Márcio; Mugerwa, Badru; Nagamasu, Hidetoshi; Nilus, Reuben; Ochoa-Gaona, Susana; Onrizal; Page, Navendu; Parolin, Pia; Parren, Marc; Parthasarathy, Narayanaswamy; Paudel, Ekananda; Permana, Andrea; Piedade, Maria T F; Pitman, Nigel C A; Poorter, Lourens; Poulsen, Axel D; Poulsen, John; Powers, Jennifer; Prasad, Rama C; Puyravaud, Jean-Philippe; Razafimahaimodison, Jean-Claude; Reitsma, Jan; Dos Santos, João Roberto; Roberto Spironello, Wilson; Romero-Saltos, Hugo; Rovero, Francesco; Rozak, Andes Hamuraby; Ruokolainen, Kalle; Rutishauser, Ervan; Saiter, Felipe; Saner, Philippe; Santos, Braulio A; Santos, Fernanda; Sarker, Swapan K; Satdichanh, Manichanh; Schmitt, Christine B; Schöngart, Jochen; Schulze, Mark; Suganuma, Marcio S; Sheil, Douglas; da Silva Pinheiro, Eduardo; Sist, Plinio; Stevart, Tariq; Sukumar, Raman; Sun, I-Fang; Sunderland, Terry; Sunderand, Terry; Suresh, H S; Suzuki, Eizi; Tabarelli, Marcelo; Tang, Jangwei; Targhetta, Natália; Theilade, Ida; Thomas, Duncan W; Tchouto, Peguy; Hurtado, Johanna; Valencia, Renato; van Valkenburg, Johan L C H; Van Do, Tran; Vasquez, Rodolfo; Verbeeck, Hans; Adekunle, Victor; Vieira, Simone A; Webb, Campbell O; Whitfeld, Timothy; Wich, Serge A; Williams, John; Wittmann, Florian; Wöll, Hannsjoerg; Yang, Xiaobo; Adou Yao, C Yves; Yap, Sandra L; Yoneda, Tsuyoshi; Zahawi, Rakan A; Zakaria, Rahmad; Zang, Runguo; de Assis, Rafael L; Garcia Luize, Bruno; Venticinque, Eduardo M

2015-06-16

The high species richness of tropical forests has long been recognized, yet there remains substantial uncertainty regarding the actual number of tropical tree species. Using a pantropical tree inventory database from closed canopy forests, consisting of 657,630 trees belonging to 11,371 species, we use a fitted value of Fisher's alpha and an approximate pantropical stem total to estimate the minimum number of tropical forest tree species to fall between ∼ 40,000 and ∼ 53,000, i.e., at the high end of previous estimates. Contrary to common assumption, the Indo-Pacific region was found to be as species-rich as the Neotropics, with both regions having a minimum of ∼ 19,000-25,000 tree species. Continental Africa is relatively depauperate with a minimum of ∼ 4,500-6,000 tree species. Very few species are shared among the African, American, and the Indo-Pacific regions. We provide a methodological framework for estimating species richness in trees that may help refine species richness estimates of tree-dependent taxa.

Evaluation of urban environment pollution based on the accumulation of macro- and trace elements in epiphytic lichens.

PubMed

Parzych, Agnieszka; Astel, Aleksander; Zduńczyk, Anna; Surowiec, Tomasz

2016-01-01

Nitrogen, phosphorus, potassium, magnesium, zinc, nickel, copper, manganese, iron and lead accumulation properties of three epiphytic lichen species (Hypogymnia physodes (L.) Nyl., Parmelia sulcata Taylor and Xanthoria parietina (L.) Th. Fr.) were compared. An assessment of pollution of the municipal environment in Słupsk (Poland) according to macro- and trace elements was also done. Lichen samples were taken in Autumn 2013 from Betula pendula, Fraxinus excelsior, Acer platanoides, A. pseudoplatanus and Populus sp. trees. Sampling stations comprised of house development areas, green urban parks, vicinity of streets with heavy traffic and industrial enterprises. It was found that lichens represent diverse accumulation properties to pollutants according to the species. X. parietina indicated the highest bioaccumulation in relation to N, K, Mg, Zn and Fe, the thalli of H. physodes accumulated the largest amounts of Ni and Pb, while P. sulcata P and Cu. Manganese was accumulated in similar quantities by all species. Evidences acquired by the use of factor analysis proved that pollution in Słupsk municipal environment is a serious issue with three major sources domination: street dust, marine factor and residual oil combustion. The high-risk areas were detected and visualized using surface maps based on Kriging algorithm. It was seen that the highest pollution occurs in the town centre, while the smallest happened on its outskirts and in urban parks.

Differential Impact of Passive versus Active Irrigation on Urban Forests in Semiarid Regions

NASA Astrophysics Data System (ADS)

Luketich, A. M.; Papuga, S. A.; Crimmins, M.

2017-12-01

The network of trees within a city provides a variety of ecosystem services such as flood mitigation and reduced heat island effects. To maintain these `urban forests' in semiarid cities, the use of scarce water resources for irrigation is often necessary. Rainwater harvesting has been widely adopted in Tucson, AZ as a sustainable water source for trees, but the effects of passive water harvesting versus active irrigation on tree canopy productivity and microclimate is largely unquantified. We hypothesize that regardless of whether trees are passively or actively irrigated, deep soil moisture will be elevated compared to natural conditions; however, we expect that increased deep soil moisture conditions will be more frequent using active irrigation. Additionally, we hypothesize that similar to natural settings, urban trees will need access deep soil moisture for transpiration. Therefore, we expect that actively irrigated trees will have more periods of transpiration than passively irrigated trees and that this will result in elevated and sustained phenological activity. We also expect that this difference will translate to more ecosystem services for a longer portion of the year in actively irrigated urban forests. Here, we compare key ecohydrological indicators of passive and active irrigation systems at two sites in Tucson, AZ. Our measurements include soil moisture, transpiration, air temperature, soil temperature, below- and within- canopy temperatures, and canopy phenology. Our first year of results suggest there are differences in transpiration, canopy greening and microclimate between the two irrigation techniques and that the magnitude of these differences are highly seasonal. This research can help to improve understanding of the practices and function of green infrastructure in semiarid cities and inform models that attempt to aggregate the influence of these urban forests for understanding watershed management strategies.

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

Treesearch

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...

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

Treesearch

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...

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

PubMed Central

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

2016-01-01

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. PMID:27641002

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

PubMed

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.

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

NASA Astrophysics Data System (ADS)

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

2016-09-01

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.

The Composition and Characteristics of the Dendroflora in the Transformed Conditions of the Middle Reaches of the River Khoper

NASA Astrophysics Data System (ADS)

Larionov, M. V.; Larionov, N. V.; Siraeva, I. S.; Ermolenko, A. S.

2018-01-01

Green plantings of the cities perform a number of important functions which provide ecological needs of cities population for a healthy surrounding medium, and his needs for communication with wildlife. The comparative analysis of species of wood plants of the towns of the Voronezh region (Borisoglebsk and Novokhopersk) was carried out. 110 types (to Borisoglebsk) and 91 species (to Novokhopersk) species of trees and bushes are registered. The systematic structure which showed a dominance of angiospermous plants that in general is characteristic of the urbanized territories. The range of geographical elements is presented by three types (European-West Asian - 35% and 40%, European - 30% and 26%, North -American - 14% and 21%). The prevailing life forms of the cities are trees, they make 56% and 60% respectively. Researchers showed, in the cities of east part of the Voronezh region many types of various origin can grow that helps to solve problems in gardening, afforestation and an agrarian and forest melioration, in creation of dendrology nurseries for the purpose of maintaining a genetic variety and the subsequent introduction of wood plants and bushes in culture.

Ecology of red swamps in the glaciated northeast: a community profile

USGS Publications Warehouse

Golet, Francis C.; Calhoun, Aram J.K.; DeRagon, William R.

1993-01-01

This report is part of a series of profiles on the ecology of wetland and deepwater habitats. This particular profile addresses red maple swamps in the glaciated northeastern United States. Red maple (Acer rubrum) swamp is a dominant wetland type in most of the region; it reaches its greatest abundance in southern New England and northern New Jersey, where it comprises 60-800/o of all inland wetlands. Red maple swamps occur in a wide variety of hydrogeologic settings, from small, isolated basins in till or glaciofluvial deposits to extensive wetland complexes on glacial lake beds, and from hillside seeps to stream floodplains and lake edges. Individual swamps may be seasonally flooded, temporarily flooded, or seasonally saturated, and soils may be mineral or organic. As many as five distinct vegetation layers may occur in these swamps, including trees, saplings, shrubs, herbs, and ground cover plants such as bryophytes and clubmosses. On a regional scale, red maple swamps support at least 50 species of trees, more than 90 species of shrubs and vines, and more than 300 species of nonwoody plants. These swamps also provide habitat for a rich faunal community, including several wetland-dependent species. In areas that are becoming urbanized, these wetlands often constitute critical habitat for facultative species as well. Red maple swamps also are important sites for flood storage, water quality improvement, recreation, scenic beauty, and open space.

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

PubMed

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.