Thesis (M.Phil.)--University of Hong Kong, 1999. / Includes bibliographical references (leaves 359-374) Also available in print.

A arborização viária é um importante elemento ambiental que mitiga os efeitos que o processo de urbanização causa sobre o ambiente. São vários os fatores que se relacionam ao bom desenvolvimento das árvores nas cidades, entre os quais está o gerenciamento pelo poder público, a percepção dos moradores e as condições ambientais em que estão se desenvolvendo as espécies, principalmente as condições do solo. Assim, o presente trabalho teve como objetivo avaliar relações entre o solo, os moradores e as espécies arbóreas implicadas na arborização urbana no município de Pato Branco. Para tanto, delimitou-se como área de estudo cinco bairros com diferentes características de localização e renda no município: Centro, La Salle, Pinheiros, Aeroporto e Veneza. As espécies estudadas foram Lagerstroemia indica L. (extremosa), Schinus molle L. (aroeira), e Bauhinia variegata L. (pata-de-vaca), escolhidas por sua representatividade na arborização da cidade. Avaliou-se o solo utilizado por 114 indivíduos arbóreos nos cinco bairros e foram aplicados 123 questionários semi estruturados a fim de entender como os moradores desses bairros percebem a arborização urbana. Os resultados da pesquisa indicam que há uma grande variabilidade de características dos solos estudados, os quais apresentam incorporação de materiais antrópicos, inversão de horizontes e ausência de camada orgânica em decomposição. Os resultados de granulometria revelaram que apesar da variabilidade de texturas nos pontos avaliados, a maioria dos solos analisados se enquadra na classe textural muito argilosa ou argilosa. O processo de urbanização da cidade de Pato Branco alterou substancialmente as propriedades químicas dos solos das espécies estudadas, sendo que a maioria apresentou relativo enriquecimento em bases trocáveis, o que antagoniza com a usual baixa fertilidade natural dos solos de Pato Branco. Também houve diferenças químicas quanto aos solos impermeabilizados pelo pavimento e não impermeabilizados, sendo que solos impermeabilizados apresentaram menores valores de matéria orgânica e maiores valores de Ca e pH. Os solos do bairro Centro parecem ser os mais alterados pelo processo de urbanização, sendo esse o bairro onde há maior porcentagem de areia adicionada ao solo, maior impermeabilização e quantidade de materiais advindos da construção civil. Quanto à percepção dos moradores, de forma geral os entrevistados parecem reconhecer a importância e as funções da arborização urbana. Entre os problemas percebidos pelos sujeitos da pesquisa, muitos são de ordem técnica e poderiam ser evitados através de um planejamento eficiente. Outros problemas percebidos são de ordem cultural, mais complexos e de difícil resolução. Os munícipes preferem principalmente as espécies que apresentam atrativos como floradas exuberantes e parecem valorizar as árvores que eles próprios escolheram para ter em frente às suas casas. Nesse sentido, é importante que as estratégias adotadas pelo poder público se ajustem às necessidades locais, preservem aspectos culturais, e contemplem, além dos aspectos técnicos relacionados à arborização, outros 9 aspectos de caráter mais lúdico, que atraiam e estimulem a população a se comprometerem com a mesma. / The street forestation is an important environmental element that mitigates the effects which the process of urbanization on the environment causes. There are various factors that relate to the good development of trees in cities; among them are the management by the government, the residents’ perception and the environmental conditions in which the species are evolving, especially soil conditions. Thus, the present study aimed to evaluate relationships between soil, residents and the arboreal species regarding the urban forestry in Pato Branco. Therefore, it was delimited as study area five neighborhoods with different characteristics of location and income in the county: Centro, La Salle, Pinheiros, Aeroporto e Veneza. Lagerstroemia indica L. (crape myrtle), Schinus molle L. (california pepper tree), and Bauhinia variegata L. (orchid tree) were the species studied, chosen by their representation in the forestation of the city. It was evaluated the soil used by 114 tree individuals in the five neighborhoods and 123 semi-structured questionnaires were administered in order to understand how the residents of these neighborhoods perceive the urban forestation. The survey results indicate that there is a great variability concerning the characteristics of the soils studied which present incorporation of anthropogenic materials, inversion of horizons and absence of decaying organic layer. The results of sieve analysis showed that despite the variability of textures in evaluated points, most soils analyzed fit in the texture class of very clayey or loamy. The urbanization process in the city of Pato Branco has fundamentally altered the chemical properties of soils of the studied species, since most of them showed relative enrichment in exchangeable bases, which antagonizes with the low natural fertility of soils in Pato Branco. There were also chemical differences regarding the impermeable soils by pavement and the ones not impermeable, the impermeable soils presented lower levels of organic matter and higher values of Ca and pH. The soils in the center area seem to be the most affected by the urbanization process, where there is a higher percentage of sand added to the soil, and greater amount of waterproofing materials coming from civil construction. Regarding the perception of residents, in general the interviewees seem to recognize the importance and function of urban forestation. Among the problems perceived by the research subjects, many are technical in nature and could be avoided through an efficient planning. Other observed problems are cultural, more complex and difficult to solve. Residents prefer mainly the species that have attractive such as exuberant blooms and they seem to appreciate trees that they chose by themselves to have in front of their homes. Therefore, it is important to adjust the strategies adopted by the government to the local needs, preserve the cultural aspects, and contemplate besides the technical aspects related to forestation, other aspects in a ludic way, to attract and encourage people to commit themselves with forestation.

Orientador: João Roberto Gomes de Faria / Banca: Maria Solange G. de Fontes / Banca: Lea Cristina Lucas de Souza / Resumo: A arborização de vias urbanas pode se constituir num elemento bastante eficaz na amenização de altas temperaturas na camada intraurbana, através de mecanismos de sombreamento e evapotranspiração. Entretanto, entre os variados tipos de espécies arbóreas, quais seriam as mais indicadas para utilização na arborização das vias, a fim de mitigar a temperatura do ar no ambiente urbano? A utilização de ferramentas computacionais é uma alternativa para análise desta questão, tendo em vista que, o uso destes programas auxilia as pesquisas na área de planejamento e avaliação do ambiente construído, por meio da simulação de variados cenários. Um programa bastante utilizado para estudos de interação entre a vegetação e microclimas urbanos é o ENVI-Met, o qual, no entanto, não contém em seu banco de dados, parâmetros relativos a espécies brasileiras, em particular as de cerrado, o que pode gerar cenários microclimáticos incorretos. O objetivo desta pesquisa é propor um método para avaliação do potencial de sombreamento de espécies usadas em arborização de vias urbanas. Para tanto, foram realizados medições de radiação solar incidente sob copas de algumas espécies, usadas no sombreamento de vias urbanas da cidade de Bauru (SP), cujos resultados foram comparados com os parâmetros das mesmas espécies simulados pelo ENVI-Met. A partir do tratamento dos dados foi gerada uma ferramenta, através da qual é possível extrapolar os resultados para escolha de outras espécies. Assim, espera-se que est... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The afforestation of the urban streets can be a very effective element in the mitigation of high temperatures in urban layer through shading mechanisms and evapotranspiration. However, among the various types of tree species, which are the best indicated for use in street afforestation, to mitigate the air temperature in the urban environment? The use of computational tools would be an alternative to analyze this question, given that the use of these programs help in the research on planning and evaluation of the built environment through the simulation of various scenarios. A program widely used to study the interaction between urban vegetation and microclimates is the ENVI-Met, which, however, does not contain parameters in your database relating to brazilians species, particularly the cerrado species, which can create incorrect microclimatic scenarios. The aims of this research is to propose a method to evaluation of potencial shading of species used in afforestation of urban streets. For that, radiation measurements were performed in incident solar canopies of some species used in shading urban streets of the city of Bauru (SP), whose results were compared with the parameters of the same species simulated by ENVI-Met. From the processing, a tool was generated through which it is possible to extrapolate the results to select other species. Thus, it is expected that this method contributes to the indication of species that contain potential for mitigating the air temperatur... (Complete abstract click electronic access below) / Mestre

In Vancouver, British Columbia, Canada, issues once thought isolated to large metropolitan areas such as Los Angeles, Tokyo, and Mexico City—increased storm water runoff, the urban heat island effect, deterioration of air and water quality, and loss of habitat and biodiversity—now threaten a region once described as "lotus-land" (Wynn and Oke, 1992, xi). European research supports the ability of green roofs to mitigate many of these ill effects of urbanization. The investigation undertaken by this thesis explores the role green roofs might play in the Greater Vancouver's transition to sustainable design and development. The thesis limits the scope of its investigation to inaccessible, extensive systems, alternately known as eco-roofs, which are relatively lightweight and low-maintenance. The paper reviews the historical and contemporary development of eco-roofs, including past and present motivations for their use and the evolution of construction methods. It then summarizes the potential impacts—aesthetic improvements, increased biodiversity, protection of the roof membrane, meso and microclimate mitigation, improved building insulation, and stormwater management—currently attributed to green roof implementation. The remainder of the thesis evaluates which of these potential impacts apply to Vancouver, in light of the city's physical contextual setting, and the ambient influences of the Greater Regional District The reported benefits of green roofs are numerous, and incremental contributions to improving environmental conditions should not be discounted or trivialized, however, in Vancouver and its region, eco-roofs' greatest impact, and consequently financial feasibility, resides in the mitigation of stormwater volumes. Eco-roofs' detain rainfall and slow runoff from the roof during and immediately following a storm event. This reduces peak flows, and corresponding CSO and flooding problems, and encourages a more natural hydrology by increasing the chances for stormwater infiltration. Storm runoff, and issues related to it, constitutes a persistent and growing problem in the GVRD. The ability of an eco-roofs even thin profile to mitigate this pressing issue could result in widespread, and even unforeseen, positive ramifications. / Applied Science, Faculty of / Architecture and Landscape Architecture (SALA), School of / Graduate

No description available.

Our climate and our cities are changing. Though their changes are not completely dependent upon one another, there is still a coupling effect between them. This study assesses the role of urban form as it pertains to elements of climate change. It is comprised of two essays intended for publication. The first of these essays addresses the feedbacks between urban form, energy consumption, and rising global temperatures. The second essay looks at one particular factor of urban form--tree type--as it pertains to air pollution and urban heat island mitigation. Both papers use the analytical approaches necessary to answer the questions they pose, not ubiquitous over-generalizing modeling software or methods found often in the literature. As seen in the analyses, this practice--known as geocomputation--allows for a deeper and more accurate description of complex spatial relationships.

published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

I hypothesized that Douglas-fir trees (Pseudotsuga menziesii) standing apart from other trees ('open-grown') will intercept more rainfall than Douglas-fir trees standing near other trees ('closed-canopy'). Open-grown trees differ structurally and are more common in urban settings, yet have been infrequently studied. Existing literature, based primarily on closed-canopy trees, suggests Douglas-fir trees in Pacific Northwest forests intercept approximately 25% of rainfall annually. Because open-grown trees have more vertical leaf area than individual trees in closed-canopy forests, I expected to find higher interception by open-grown trees. I collected throughfall under four open-grown Douglas-firs using six static collectors ('buckets') per tree, and two closed-canopy Douglas-firs using six buckets per tree. I compared their throughfall to the incident rainfall in two adjacent open-field buckets. Gross interception was measured in 53 collections during rainy weather from 16Nov07 to 31Mar08. Over the same period, rainfall per hour, wind speed, gust speed, wind direction, temperature and relative humidity were collected at a weather station located within 1 km of the site. For comparison, average hourly rainfall at Portland International Airport from 1950 to 2005, for the same months of the collection period, showed a comparable number of medium- to high-intensity storms, but more low-intensity storms. I found that incident rainfall for the adjacent open-field buckets totaled 65.6cm and 71.6cm over the study period. Interception values for closed-canopy trees averaged 26%, corresponding to the literature, with results of 22 and 30%. Interception values for open-grown trees averaged 31%, with results ranging from 15 to 45%. Three of the 24 buckets returned overall negative interception rates over five months. Given the lower storm intensity of 2007-08, interception rates may be somewhat high, compared to the historical average. The negative interception rates at three buckets were likely due to their locations under high drip points, as has been observed in other studies. Considering the wide range of canopy architecture among open-grown trees, the high variability in interception was not surprising. My hypothesis was supported by the data, but requires more testing to better generalize these results. Future studies that link open grown tree canopy morphological characteristics to interception are warranted.

Regression models were developed to predict scenic quality for residential streets in Ann Arbor, Michigan for both Summer and Winter vegetative conditions. Scenic quality was quantified using the Scenic Beauty Estimation method. Only variables that existed in the city's computer data base were used. Variables such as diameter at breast height, basal area, number of trees, and tree species diversity were investigated as to their predictive ability. In addition, the predictive ability of quadratic, power, inverse, and logarithmic transformations of these variables was investigated. The best predictive Summer model used the natural log of the average diameter of street trees and the natural log of the average assessed property value as variables. The best predictive Winter model used the natural log of the average diameter of street trees as its independent variable. / Master of Science / incomplete_metadata

published_or_final_version / Geography and Geology / Master / Master of Philosophy