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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Uprooting People, Planting Trees: Environmental Scarcity Politics and Urban Greening in Beijing

Kay, Samuel 07 October 2020 (has links)
No description available.
112

Functional Ecology and Ecosystem Services of Urban Trees

Simovic, Milos 14 September 2020 (has links)
No description available.
113

Towards Spatio-temporally Integrated Design and Operations of Techno-Ecological Synergistic Systems

Shah, Utkarsh Dinesh 13 September 2022 (has links)
No description available.
114

TREE HEALTH, CARBON SEQUESTRATION, AND SUSTAINABILITY OF URBAN FORESTS

Chiriboga, Christian Alejandro 06 August 2013 (has links)
No description available.
115

Partizipative Prozesse in stadtnahen Waldlandschaften am Beispiel von Kommunalwäldern in Deutschland

Böhnke-Förster, Pia Maria Petra 14 January 2013 (has links)
Die vorliegende Arbeit „Partizipative Prozesse in stadtnahen Waldlandschaften am Beispiel von Kommunalwäldern in Deutschland“ setzt sich mit der Anwendung partizipativer Verfahren bei der Entscheidungsvorbereitung, -findung und -umsetzung in kommunalen Forstbetrieben in Deutschland auseinander. Die Partizipation von externen Gruppen oder Individuen an Entscheidungen wird als mehrstufiger Prozess hinsichtlich ihrer Anwendung in ausgewählten Kommunalwäldern analysiert. Auf kommunaler Ebene stellen politische Wahlen das klassische Beteiligungsangebot an die Gemeindebürger dar und bilden die Grundlage für die Entscheidungsfindung. Neben dieser Art der gesetzlich verankerten Beteiligungsverfahren rücken in der gesellschaftlichen und wissenschaftlichen Diskussion nicht-institutionalisierte Beteiligungsverfahren der kooperativen Demokratie mehr und mehr in den Fokus. Es ergeben sich die grundlegenden Fragen: (1) Wo, wann, wie und in welchem Umfang werden in Deutschland im Kommunalwald partizipative Prozesse durchgeführt? (2) Wie können Partizipationsprozesse im Kommunalwald charakterisiert werden? (3) Welche Intention wird mit dem Einsatz partizipativer Prozesse im Kommunalwald verfolgt? (4) Welche Rahmenbedingungen sind für die Durchführung partizipativer Prozesse im Kommunalwald notwendig? (5) In welchen Situationen sind partizipative Prozesse alternative Methoden zur klassischen Entscheidungsfindung im stadtnahen Wald? (6) Auf welche Art, mit welchem Organisationsgrad und welcher Intensität lassen sich partizipative Ansätze in bestehende Kommunalverwaltungsstrukturen integrieren? Die Untersuchung erfolgt anhand einer qualitativen, explorativen Studie von 13 deutschen Gemeinden in Sachsen, Nordrhein-Westfalen, Berlin-Brandenburg, Schleswig-Holstein und Baden-Württemberg unterschiedlicher Einwohnerzahlen, Waldbesitzgrößen und Organisationsformen.:Danksagung II Inhaltsverzeichnis III Abbildungsverzeichnis VI Tabellenverzeichnis VIII Abkürzungsverzeichnis IX Abstract XI Participatory processes in peri-urban forest landscapes illustrated using the example of community forests in Germany XI 1 Thematische Einordnung, Problemstellung und Zielsetzung 1 1.1 Problemstellung und Zielsetzung der Forschungsarbeit 1 1.2 Stand der Forschung 5 1.3 Forschungsdesign 9 1.4 Aufbau der Arbeit 11 1.5 Untersuchungsgegenstand 12 1.5.1 Begriffsabgrenzung 12 1.5.2 Zuständigkeiten, Besitz- und Organisationsformen im Kommunalwald in Deutschland 16 2 Theoretischer Bezugsrahmen 20 2.1 Partizipationsprozesse 20 2.1.1 Partizipatorische Demokratietheorien 20 2.1.2 Begriffskonzepte 23 2.1.3 Partizipationsmodelle 27 2.1.4 Partizipationsprozesse im kommunalen Kontext 32 2.1.5 Möglichkeiten und Grenzen partizipativer Entscheidungsprozesse 35 2.2 Urbane Wälder und urbane Forstwirtschaft 38 2.3 Kommunalwald in Deutschland 41 2.3.1 Kommunalpolitischer Hintergrund 41 2.3.2 Wald in der Kommunalpolitik 47 2.4 Urban (Forest) Governance 48 2.4.1 Urban Governance 48 2.4.2 Urban Forest Governance 52 3 Konkretisierung der Leitfragen in Form von Forschungsfragen / Erhebungsmodell 53 4 Methodisches Vorgehen 56 4.1 Methodologische Grundlagen 56 4.2 Empirische Erhebung 58 4.2.1 Übersicht über Methodenwahl und Auswertungsdesign 58 4.2.2 Experteninterviews 59 4.2.3 Entwicklung des Leitfadens 60 4.2.4 Auswahl der Fallbeispiele und Interviewpartner 62 4.2.5 Durchführung der Experteninterviews 67 4.3 Auswertung 67 4.3.1 Transkriptionspraxis 67 4.3.2 Auswertungsmethoden 68 4.3.3 Die Entwicklung des Kategoriensystems 72 4.3.4 Einsatz von QDA-Software / MaxQDA 75 5 Ergebnisse der empirischen Erhebung 77 5.1 Darstellung der Ergebnisse 77 5.1.1 Visualisierung des Gesprächsverlaufs – Interview Portraits 79 5.2 Komplex 1 / Informationen zur Institution und Kategorisierung der Fallbeispiele 80 5.3 Komplex 2 / Aktuelle Themenkomplexe und Problemfelder des Kommunalwalds 89 5.4 Komplex 3 / Entscheidungsfindung im Kommunalwald im System der repräsentativen Demokratie 91 5.4.1 Unterschiedliche Entscheidungsebenen und Beschreibungsdimensionen 91 5.4.2 Weg und Akteure der Entscheidungsfindung 93 5.5 Komplex 4 / Partizipation bei der Entscheidungsfindung im Kommunalwald 101 5.5.1 Durch Rechtssätze verankerte Beteiligungsverfahren mit Relevanz für die Entscheidungsfindung im Kommunalwald 101 5.5.2 Freiwillige Beteiligungsprozesse mit Relevanz für den Kommunalwald 103 5.5.3 Akteure der Partizipation 107 5.5.4 Rahmenbedingungen und Themenkomplexe für Partizipationsprozesse 110 5.5.5 Stellenwert von Partizipation 114 5.6 Komplex 5 / Verknüpfungen von Urban Governance Konzepten und Planungen im stadtnahen Wald 119 6 Diskussion der Leit- und Forschungsfragen 122 6.1 Diskussion Leitfrage 1: Wo, wann und in welchem Umfang werden in Deutschland im Kommunalwald partizipative Prozesse durchgeführt? 122 6.1.1 Wer ist an der Entscheidungsfindung im Kommunalwald im System der repräsentativen Demokratie beteiligt? 122 6.1.2 Welche Rolle spielen partizipative Prozesse zur Entscheidungsfindung im Kommunalwald? 124 6.1.3 Zu welchem Zeitpunkt im Policy-Zyklus wird durch Partizipationsprozesse auf den Kommunalwald Einfluss genommen? 126 6.1.4 In welchem Umfang werden Partizipationsprozesse durchgeführt? 128 6.1.5 Bestehen Unterschiede in Art und Ausmaß partizipativer Prozesse im Kommunalwald zwischen alten und neuen Bundesländern? 129 6.1.6 Unterschiede in Abhängigkeit von der Waldbesitzgröße 129 6.2 Diskussion Leitfrage 2: Wie können Partizipationsprozesse im Kommunalwald charakterisiert werden? 130 6.2.1 Welche Akteure werden im Kommunalwald zum aktuellen Zeitpunkt beteiligt? 130 6.2.2 In welchen Fällen fungiert der Bürger in Beteiligungsprozessen im Kommunalwald als Auftraggeber oder Mitgestalter? 133 6.2.3 Welchen Stufen sind Beteiligungsprozesse im Kommunalwald zuzuordnen? Existieren Prozesse auf Ebene der Mitgestaltung? 134 6.2.4 Welche der angewandten Verfahren können den kooperativen und welche den gesetzlich verankerten Beteiligungsformen zugeordnet werden? 136 6.2.5 Welche Themen werden im Kommunalwald partizipativ bearbeitet? 141 6.3 Diskussion Leitfrage 3: Welche Intention wird mit dem Einsatz partizipativer Prozesse im Kommunalwald verfolgt? 146 6.3.1 Welche Intention verfolgen die Entscheidungsträger mit dem Einsatz partizipativer Prozesse im Kommunalwald? 146 6.3.2 Wer initiiert Beteiligungsprozesse im Kommunalwald? 148 6.4 Welche Rahmenbedingungen sind für die Durchführung partizipativer Prozesse im Kommunalwald notwendig? 149 6.4.1 Können Erfolgsfaktoren und Hemmnisse von Partizipationsprozessen im Kommunalwald ausgeschieden werden? 149 6.4.2 Welche externen Rahmenbedingungen sind Voraussetzung für erfolgreiche partizipative Prozesse im Kommunalwald? Können externe und interne Rahmenbedingungen für Partizipationsprozesse im Kommunalwald unterschieden werden? 150 6.5 Auf welche Art, mit welchem Organisationsgrad und welcher Intensität lassen sich partizipative Ansätze in bestehende Kommunalverwaltungsstrukturen integrieren? 152 6.5.1 Handlungsstrategien der forstlichen Verwaltungsebene und der forstbetrieblichen Institutionen im Kommunalwald 152 6.5.2 Wird der Kommunalwald an Urban Governance Konzepten beteiligt? 157 6.6 Methodenkritik 160 7 Ausblick 164 8 Zusammenfassung 166 Literaturverzeichnis 169 Anhang 180 / Political elections represent the conventional form of public participation at the municipal level and create the foundations for decision making. In addition to these legally anchored forms of public participation, non-institutionalised forms of participation stemming from cooperative democracy are increasingly becoming the focus of scientific and social discourse. The research presented herein focused on community forestry in Germany and represented an attempt to find answers to six questions. (1) How are citizen participation methods currently used? (2) How can participation processes be characterised? (3) What is the intention behind Tit? (4) What framework is required for utilisation? (5) In which situations is participation an alternative method to top-down decision making? (6) In which mode and at what level of organisation and intensity can participatory approaches be integrated in communal administration structures? A qualitative, explorative study of participative processes employed in developing urban and peri-urban forest landscapes was designed:Danksagung II Inhaltsverzeichnis III Abbildungsverzeichnis VI Tabellenverzeichnis VIII Abkürzungsverzeichnis IX Abstract XI Participatory processes in peri-urban forest landscapes illustrated using the example of community forests in Germany XI 1 Thematische Einordnung, Problemstellung und Zielsetzung 1 1.1 Problemstellung und Zielsetzung der Forschungsarbeit 1 1.2 Stand der Forschung 5 1.3 Forschungsdesign 9 1.4 Aufbau der Arbeit 11 1.5 Untersuchungsgegenstand 12 1.5.1 Begriffsabgrenzung 12 1.5.2 Zuständigkeiten, Besitz- und Organisationsformen im Kommunalwald in Deutschland 16 2 Theoretischer Bezugsrahmen 20 2.1 Partizipationsprozesse 20 2.1.1 Partizipatorische Demokratietheorien 20 2.1.2 Begriffskonzepte 23 2.1.3 Partizipationsmodelle 27 2.1.4 Partizipationsprozesse im kommunalen Kontext 32 2.1.5 Möglichkeiten und Grenzen partizipativer Entscheidungsprozesse 35 2.2 Urbane Wälder und urbane Forstwirtschaft 38 2.3 Kommunalwald in Deutschland 41 2.3.1 Kommunalpolitischer Hintergrund 41 2.3.2 Wald in der Kommunalpolitik 47 2.4 Urban (Forest) Governance 48 2.4.1 Urban Governance 48 2.4.2 Urban Forest Governance 52 3 Konkretisierung der Leitfragen in Form von Forschungsfragen / Erhebungsmodell 53 4 Methodisches Vorgehen 56 4.1 Methodologische Grundlagen 56 4.2 Empirische Erhebung 58 4.2.1 Übersicht über Methodenwahl und Auswertungsdesign 58 4.2.2 Experteninterviews 59 4.2.3 Entwicklung des Leitfadens 60 4.2.4 Auswahl der Fallbeispiele und Interviewpartner 62 4.2.5 Durchführung der Experteninterviews 67 4.3 Auswertung 67 4.3.1 Transkriptionspraxis 67 4.3.2 Auswertungsmethoden 68 4.3.3 Die Entwicklung des Kategoriensystems 72 4.3.4 Einsatz von QDA-Software / MaxQDA 75 5 Ergebnisse der empirischen Erhebung 77 5.1 Darstellung der Ergebnisse 77 5.1.1 Visualisierung des Gesprächsverlaufs – Interview Portraits 79 5.2 Komplex 1 / Informationen zur Institution und Kategorisierung der Fallbeispiele 80 5.3 Komplex 2 / Aktuelle Themenkomplexe und Problemfelder des Kommunalwalds 89 5.4 Komplex 3 / Entscheidungsfindung im Kommunalwald im System der repräsentativen Demokratie 91 5.4.1 Unterschiedliche Entscheidungsebenen und Beschreibungsdimensionen 91 5.4.2 Weg und Akteure der Entscheidungsfindung 93 5.5 Komplex 4 / Partizipation bei der Entscheidungsfindung im Kommunalwald 101 5.5.1 Durch Rechtssätze verankerte Beteiligungsverfahren mit Relevanz für die Entscheidungsfindung im Kommunalwald 101 5.5.2 Freiwillige Beteiligungsprozesse mit Relevanz für den Kommunalwald 103 5.5.3 Akteure der Partizipation 107 5.5.4 Rahmenbedingungen und Themenkomplexe für Partizipationsprozesse 110 5.5.5 Stellenwert von Partizipation 114 5.6 Komplex 5 / Verknüpfungen von Urban Governance Konzepten und Planungen im stadtnahen Wald 119 6 Diskussion der Leit- und Forschungsfragen 122 6.1 Diskussion Leitfrage 1: Wo, wann und in welchem Umfang werden in Deutschland im Kommunalwald partizipative Prozesse durchgeführt? 122 6.1.1 Wer ist an der Entscheidungsfindung im Kommunalwald im System der repräsentativen Demokratie beteiligt? 122 6.1.2 Welche Rolle spielen partizipative Prozesse zur Entscheidungsfindung im Kommunalwald? 124 6.1.3 Zu welchem Zeitpunkt im Policy-Zyklus wird durch Partizipationsprozesse auf den Kommunalwald Einfluss genommen? 126 6.1.4 In welchem Umfang werden Partizipationsprozesse durchgeführt? 128 6.1.5 Bestehen Unterschiede in Art und Ausmaß partizipativer Prozesse im Kommunalwald zwischen alten und neuen Bundesländern? 129 6.1.6 Unterschiede in Abhängigkeit von der Waldbesitzgröße 129 6.2 Diskussion Leitfrage 2: Wie können Partizipationsprozesse im Kommunalwald charakterisiert werden? 130 6.2.1 Welche Akteure werden im Kommunalwald zum aktuellen Zeitpunkt beteiligt? 130 6.2.2 In welchen Fällen fungiert der Bürger in Beteiligungsprozessen im Kommunalwald als Auftraggeber oder Mitgestalter? 133 6.2.3 Welchen Stufen sind Beteiligungsprozesse im Kommunalwald zuzuordnen? Existieren Prozesse auf Ebene der Mitgestaltung? 134 6.2.4 Welche der angewandten Verfahren können den kooperativen und welche den gesetzlich verankerten Beteiligungsformen zugeordnet werden? 136 6.2.5 Welche Themen werden im Kommunalwald partizipativ bearbeitet? 141 6.3 Diskussion Leitfrage 3: Welche Intention wird mit dem Einsatz partizipativer Prozesse im Kommunalwald verfolgt? 146 6.3.1 Welche Intention verfolgen die Entscheidungsträger mit dem Einsatz partizipativer Prozesse im Kommunalwald? 146 6.3.2 Wer initiiert Beteiligungsprozesse im Kommunalwald? 148 6.4 Welche Rahmenbedingungen sind für die Durchführung partizipativer Prozesse im Kommunalwald notwendig? 149 6.4.1 Können Erfolgsfaktoren und Hemmnisse von Partizipationsprozessen im Kommunalwald ausgeschieden werden? 149 6.4.2 Welche externen Rahmenbedingungen sind Voraussetzung für erfolgreiche partizipative Prozesse im Kommunalwald? Können externe und interne Rahmenbedingungen für Partizipationsprozesse im Kommunalwald unterschieden werden? 150 6.5 Auf welche Art, mit welchem Organisationsgrad und welcher Intensität lassen sich partizipative Ansätze in bestehende Kommunalverwaltungsstrukturen integrieren? 152 6.5.1 Handlungsstrategien der forstlichen Verwaltungsebene und der forstbetrieblichen Institutionen im Kommunalwald 152 6.5.2 Wird der Kommunalwald an Urban Governance Konzepten beteiligt? 157 6.6 Methodenkritik 160 7 Ausblick 164 8 Zusammenfassung 166 Literaturverzeichnis 169 Anhang 180
116

Development of Urban Tree Growth Models Based on Site and Soil Characteristics

Wenzel-Bartens, Julia 09 December 2010 (has links)
Trees provide numerous benefits crucial to urban environments, yet poor growing conditions often prevent trees from reaching their genetic potential for growth, longevity, and ecosystem function. To overcome these limitations, greater understanding of tree growth in the urban environment is needed. The goal of this research project was therefore to characterize a broad suite of soil characteristics associated with urban tree plantings and evaluate their suitability for modeling physical dimensions and growth rates of urban trees. A series of observational studies and experiments was conducted on urban soils inhabited by two tree species (Zelkova serrata (Thunb.) Mikano and Quercus phellos L.) in Washington, DC and one tree species (Quercus virginiana Mill.) in Jacksonville, FL – two major metropolitan areas of the eastern United States with contrasting climate and soils. Characterization of urban soil attributes within cities revealed low variability for some properties (soil texture, pH, and certain plant nutrients with coefficients of variation (CV) below 0.5), but high variability (CV>1.0) for others (nitrate, ammonium, copper, and zinc). This is dependent on the location. These findings suggest that tree planting site evaluations may not require measurements for all soil properties and that representative sampling may be sufficient to accurately characterize most soil properties within a city. Field assessment of urban tree soils also revealed that conventional measures of soil compaction are difficult to obtain due to obstructions by roots and other foreign objects. To address the critical need for efficient and reliable assessment of soil compaction around urban trees, an experiment was conducted to develop bulk density estimation models for four common soil texture classes using soil strength and soil moisture as predictor variables. These models provided medium (0.42) to high (0.85) coefficients of determination when volumetric water content (VWC) was log transformed, demonstrating that measurements of soil texture, strength, and moisture can provide rapid, reliable assessment of soil compaction. Tree growth modeling focused on three response variables: canopy projection (CP), canopy volume (CV), and peak-increment-area age (PIA). To calculate PIA, tree-ring analysis was used to determine the age at which maximal trunk diameter growth occurred between transplanting and time of sampling. Because Q. virginiana has difficult-to-distinguish growth rings, an intensive tree-ring analysis of cores collected from these trees was conducted. The analysis revealed interseries correlation coefficients of up to 0.66, demonstrating that Q. virginiana can be aged with fairly high confidence in an urban setting. Empirical models developed for all three tree species using the suite of soil and site variables explained 25% – 83% of the observed variability in tree physical dimensions and growth rates. Soil pH was found to be a significant predictor variable for the majority of growth models along with nutrients such as Fe, B, Mn, and Zn, which are also associated with soil alkalinity. Models for PIA possessed the highest coefficient of determination, suggesting that measurements of soil conditions can be used confidently to predict the age at which growth rate subsides in these species. CV and CP were not predicted as well by soil-related variables, presumably because above-ground constraints such as pruning and building encroachment can affect canopy size without necessarily affecting growth rate. Certain prediction models for all three species included predictor variables with counterintuitive influences on tree growth (e.g., negative influences of soil depth on Q. phellos and soil volume on Q. virginiana), suggesting that either these urban trees are responding to these variables in a novel manner or that variables unaccounted for in these models (perhaps related to urbanization or high vehicular traffic) are concomitantly influencing tree growth. / Ph. D.
117

Trees and Structural Soil as a Stormwater Management System in Urban Settings

Bartens, Julia 11 January 2007 (has links)
Urban runoff continues to impair water quality and there is an increasing need for stormwater management within the limited confines of urban spaces. We propose a system of structural soil and trees that can be incorporated beneath pavement. Structural soil has a high load-bearing capacity yet is engineered to support tree root growth. Stormwater is directed into a structural soil reservoir below the pavement where tree roots can also thrive. Two container experiments evaluated tree function in this system. We examined whether tree roots can grow into compacted subsoils and if root penetration increases soil infiltration rate. Quercus velutina, Acer rubrum, and a no-tree variant were planted in 26.5 L (7 gal) containers and the rootballs surrounded by compacted clay loam. Roots grew into all layers of the compacted soil. Infiltration rate increased by 63% (+/-2%) compared to no-tree containers. A second experiment evaluated water uptake and tree development in fluctuating water tables. Quercus bicolor and Fraxinus pennsylvanica were planted in 94.6 L (25 gal) containers with structural soils (either Stalite or CU® Structural Soil). Trees were subjected to fluctuating water tables simulating infiltration rates of 2, 1, and 0.1 cm/hr for two growing seasons. Trees thrived in all infiltration regimes but roots were shallower in slowly drained treatments. Trees grew best and transpired the highest water volume with moderate infiltration. Even if trees uptake only small volumes of water, increased canopy size compared to conventional plantings (because of greater penetrable soil volume) allows greater rainfall interception thus decreasing runoff. / Master of Science
118

The impact of urban expansion and population growth on productivity of forestlands : study area: Rustenburg Local Municipality.

Seokwang, Modise. January 2007 (has links)
The survey has been carried out in North West Province within Rustenburg Local Municipality. This is an Urban Forestry research in which six sites including peri-urban, urban, suburban and semi-rural areas were selected for the study. The aim of the study was to determine the relationship between households and their local trees and forests. Forest in this context included community gardens, vegetation cover, open spaces, soil, water, productive sites and animals that form part of forest. Data collection was mainly based on questionnaires and covered sample of 272 households. Statistical Package of Social Sciences (SPSS) 15.0 using 5% sampling intensity (confidence level) was used in which the data has been represented by numbers. Analysis was based on determining households’ relationship with their trees and local forest, and how they influence forest productivity or development. With SPSS two techniques, regression model and descriptive statistics were applied to analyze quantitative and qualitative data. Regression model was significant in prediction of the dependent variable (Y) using independent variables (X), and proved to be a good model to analyze data for fuelwood, timber and forest food production. Descriptive statistics was important in counting number of times each category or variable is used. Participants had varying perceptions regarding the use of forest due to factors such as availability of forest resource, type of residence, and their living standard. Generally, households in suburban and urban areas value the forests for economic and environmental benefit, while the peri-urban and semi-rural households utilized their trees and forest to meet their energy demand. A large number of households consume forest food as compared to timber and fuelwood due to the availability of the resources. The Municipality as a whole is undergoing rapid development expected to continue throughout years. These developments are stimulated by mining activities and influx of people in the area. All these factors threaten the existing natural resources especially forest areas and water. Areas of these resources are declining due to the current demand for housing, new mining sites and continuous establishment of informal settlements. Trees and forest within peri-urban and semi-rural areas are in poor conditions as compared to urban and suburban areas. Poor waste management and poverty are issues aggravating the situation especially in poor developing sites that have been studied. Most agricultural sites have been transformed into residential areas, and thus exacerbating problems of food insecurity in the whole country. Household size has major influence in fuelwood, timber and forest food production as an increase or decrease in the size will determine the amount of consumption, production or development. Value for forest, access to forest, level of interaction and restrictions regarding the use of forest are also significant aspects contributing to forest productivity and development as they show the relationship that exists between forest and households. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2007.
119

Investigating the Potential of Land Use Modifications to Mitigate the Respiratory Health Impacts of NO2: A Case Study in the Portland-Vancouver Metropolitan Area

Rao, Meenakshi 02 June 2016 (has links)
The health impacts of urban air pollution are a growing concern in our rapidly urbanizing world. Urban air pollutants show high intra-urban spatial variability linked to urban land use and land cover (LULC). This correlation of air pollutants with LULC is widely recognized; LULC data is an integral input into a wide range of models, especially land use regression models developed by epidemiologists to study the impact of air pollution on human health. Given the demonstrated links between LULC and urban air pollution, and between urban air pollution and health, an interesting question arises: what is the potential of LULC modifications to mitigate the health impacts of urban air pollution? In this dissertation we assess the potential of LULC modifications to mitigate the health impacts of NO2, a respiratory irritant and strong marker for combustion-related air pollution, in the Portland-Vancouver metropolitan area in northwestern USA. We begin by measuring summer and winter NO2 in the area using a spatially dense network of passive NO2 samplers. We next develop an annual average model for NO2 based on the observational data, using random forest -- for the first time in the realm of urban air pollution -- to disentangle the effects of highly correlated LULC variables on ambient NO2 concentrations. We apply this random forest (LURF) model to a 200m spatial grid covering the study area, and use this 200m LURF model to quantify the effect of different urban land use categories on ambient concentrations of NO2. Using the changes in ambient NO2 concentrations resulting from land use modifications as input to BenMAP (a health benefits assessment tool form the US EPA), we assess the NO2-related health impact associated with each land use category and its modifications. We demonstrate how the LURF model can be used to assess the respiratory health benefits of competing land use modifications, including city-wide and local-scale mitigation strategies based on modifying tree canopy and vehicle miles traveled (VMT). Planting trees is a common land cover modification strategy undertaken by cities to reduce air pollution. Statistical models such as LUR and LURF demonstrate a correlation between tree cover and reduced air pollution, but they cannot demonstrate causation. Hence, we run the atmospheric chemistry and transport model CMAQ to examine to what extent the dry deposition mechanism can explain the reduction of NO2 which statistical models associate with tree canopy. Results from our research indicate that even though the Portland-Vancouver area is in compliance with the US EPA NO2 standards, ambient concentrations of NO2 still create an annual health burden of at least $40 million USD. Our model suggests that NO2 associated with high intensity development and VMT may be creating an annual health burden of $7 million and $3.3 million USD respectively. Existing tree canopy, on the other hand, is associated with an annual health benefit of $1.4 million USD. LULC modifications can mitigate some fraction of this health burden. A 2% increase in tree canopy across the study area may reduce incidence rates of asthma exacerbation by as much as 7%. We also find that increasing tree canopy is a more effective strategy than reducing VMT in terms of mitigating the health burden of NO2. CMAQ indicates that the amount of NO2 removed by dry deposition is an order of magnitude smaller than that predicted by our statistical model. About one-third of the difference can be explained by the lower NO2 values predicted by CMAQ, and one-third may be attributable to parameterization of stomatal uptake.
120

Qualidade do espaço verde urbano: uma proposta de índice de avaliação. / Quality of urban green space: a proposal of evaluation index.

Alvarez, Ivan André 12 April 2004 (has links)
O objetivo deste trabalho foi propor, entre os índices já existentes, um índice que avalie a qualidade da cobertura vegetal em relação à sua função ecológica, no meio urbano. Para a composição deste índice, compararam-se os métodos de amostragem aleatória simples e de amostragem estratificada de inventários da arborização de calçadas com o censo, com a finalidade de se escolher o melhor método de levantamento quali-quantitativo para árvores de calçada. Determinou-se o número de árvores por quilômetro, número total de árvores, Índice de Diversidade de Shannon (IDS) para árvores de calçada. Foram calculados o Índice de Espaços Livres de Uso Público (IELUP), a Porcentagem de Espaços Livres de Uso Público (PELUP), o Índice de Cobertura Vegetal em Áreas Urbanas (ICVAU) e o Índice de Verde por Habitante (IVH). Foram utilizadas planta baixa digital, fotografia aérea e videografia para mensurar as áreas ocupadas pela vegetação. A unidade de paisagem escolhida para estudo foi o bairro Santa Cecília em Piracicaba, Estado de São Paulo, Brasil, nos anos de 2000 a 2003. O levantamento amostral qualitativo das árvores de calçada foi feito por amostragem aleatória simples, escolhido, no trabalho, como o melhor método para inventariar árvores de rua. Considerando o ano de 2003, para a proposição do índice, os resultados obtidos foram: a) o IELUP variou de 11,42 a 41,62m2/hab (videografia); b) o PELUP variou de 1,52% a 2,89%; c) o ICVAU foi de 25,76m2 (forração + cobertura arbórea) e de 16,48 m2 (cobertura arbórea); d) o IVH foi de 101,96m2/hab (forração + cobertura arbórea) e de 65,21m2/hab (cobertura arbórea). Para a avaliação de espaços verdes urbanos foi feita discussão em função de obter-se um chamado "Índice de Qualidade do Espaço Verde Urbano" (IQEVU), particularizado para a função ecológica, então denominado "Índice de Qualidade do Espaço Verde Urbano com Função Ecológica" (IQEVUe). Os parâmetros para avaliação deste último índice foram: sombreamento, para árvores de calçadas; hidrologia, fixação de Carbono e influência de temperatura, para todos os espaços verdes. O IQEVUe mostrou-se adequado e coerente para mensurar os benefícios da vegetação em áreas urbanas, fornecendo subsídios para o planejamento e o manejo de cidades. / The aim of this work was to propose a new index, amongst other already known, that evaluates the quality of green coverage in relation to its ecological role in urban environment. To elaborate this index, simple random and stratified random sampling were compared with the census, in order to assess the best qualitative and quantitative method to do the tree inventory. A survey of sidewalk arborisation, as well as trees per kilometre, total number of trees and the Shannon Diversity Index (IDS) of sidewalk trees were evaluated. Amongst the studied indexes were the Index of Open Spaces for Public Use (IELUP), Percentage of Open Spaces for Public Use (PELUP), Index of Green Coverage for Urban Areas (ICVAU) and Index of Green per Inhabitant (IVH), by means of digital plan, aerial photography and videography for the areas covered by vegetation measurement. Santa Cecilia District in Piracicaba City, Sao Paulo State, Brazil, was the object of study from 2000 to 2003. The qualitative sampling survey of trees was carried out by simple random sampling, as found to be the most adequate to survey sidewalk trees. Data obtained for 2003, the year chosen to propose the new index, were: a) IELUP varied from 11.42 to 41.62m2/inhab, using videography; b) PELUP varied from 1.52% to 2.89%; c) ICVAU was 25.76m2 (coverage + tree canopy) and 16.48m2 ( tree canopy ); d) IVH consisted of 101.96m2/hab (coverage + tree canopy) and 65.21m2/inhab (tree canopy). The index for the evaluation of green spaces, so named "Index for Quality of Green Urban Space" (IQEVU) was one of the subsidies to study and propose the "Index for Quality of Green Urban Space with Ecological Role" (IQEVUe). The parameters for evaluation of such index were the shading from sidewalk trees; hydrology, Carbon sequestration and temperature influence for all green space. In this study, the proposed IQEVUe seems to be adequate and coherent as an evaluation method for the benefits of urban vegetation, providing subsidies for the planning and management of cities.

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