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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.
181

ECONOMIC AND ENVIRONMENTAL IMPACTS OF STORMWATER MANAGEMENT : Case study: Cost-effectiveness evaluation of Proposition O projects

Mahdian, Adrian January 2020 (has links)
Stormwater Management (SWM) or Best management practices (BMPs) treat the stormwater runoff that carries pollutants. Pollutants in the waters and in the stormwater, negatively impact the environment, the ecology, and natural resources. Stormwater Control Measures (SCM) are used in different projects to improve water quality and quantity. This thesis aims to understand the connection between SWMs, the economy, and environmental sustainability. This thesis evaluates the cost-effectiveness of SWMs in Mediterranean climates. The research aims to guide the next project managers to choose better SWMs based on cost-effectiveness, socio-economic, and environmental implications. Various studies suggest that the terms SWM, SWM, and SCM are used interchangeably. The research methodology uses a mix of qualitative and quantitative data analysis The research was conducted in Los Angeles at the request of UCLA. Therefore, it focused on water quality improvement projects in Los Angeles. The costs for the projects, areas, and whatSWMs are used will be acquired through data gathering and personal communication with experts. This thesis compares several projects which include different SWMs. It calculates the cost-effectiveness with two different methods, firstly, the cost per drainage area, and secondly, the cost per pollutant removed. Data is gathered from the city of LA and other secondary data sources to calculate the cost-effectiveness. The calculation results showed that the Glenoaksproject and the Machado lake project were the most cost-effective. Glenoaks utilizes infiltration wells and grass swales, and the Machado lake is a large wetland. Based upon these facts, generally, wetlands and grass swales can be recommended for Mediterranean climates. The expensive total costs of SWMs or their inability to remove pollutants can strongly affect the cost-effectiveness of some projects, and produce a negative impact on the economy. Quantitative assessment of study investigates cost-effectiveness of SWMs and for highlighting its economic impact. For qualitative assessment thematic analysis of 14 sample studies related to stormwater management (SWM) was carried out. Findings reveal that 78% of sample studies reflect the themes associated with the positive economic impact of SWMs. Additionally, the sample studies confirm a 76% positive impact of SWMs on the environment and ecology of the region. Further research with better data and more accurate calculations are needed. It would be beneficial if other factors such as recreation and unquantifiable factors such as the aesthetic improvements and community benefits were incorporated into or considered together with the cost-effectiveness for future projects.
182

Přírodě blízká opatření v intravilánu města Brna / Nature-friendly measures in the urban city of Brno

Svobodová, Lenka January 2022 (has links)
The thesis is focused on climate change impact in cities. In its first general section various nature-based adaptation solutions for urban areas are presented. Functional instances of finished implementations from city of Brno are named. The second, practical, section a particular proposal of nature-based solution for Brno by partial revitalization of Svratka river and its surrounding area is shown. The feasibility is supported by 1D and 2D numerical models. Crucial output of the work are technical drawings and flood simulation maps.
183

Bioretention: Evaluating their Effectiveness for Improving Water Quality in New England Urban Environments

Dehais, Mary 01 January 2011 (has links) (PDF)
Nonpoint source (NPS) pollution is one of the leading causes of water quality problems in the United States. Bioretention has become one of the more frequently used stormwater management practices for addressing NPS pollution in urbanized watersheds in New England. Yet despite increased acceptance, bioretention is not widely practiced. This study explores and evaluates the efficacy of bioretention for protecting urban water quality. This research found that numerous monitoring methods are used by researchers and industry experts to assess the effectiveness of stormwater best management practices (BMPs) and low impact development (LID) practices that include bioretention. The two most common methods for analyzing and evaluating water quality data are pollutant removal efficiency and effluent quality. While effluent quality data is useful for characterizing classes of BMP treatment performance on a statistical basis, pollutant removal efficiency is more representative of the actual pollutant load being reduced by the stormwater treatment practice over time, and is used in Total Maximum Daily Load (TMDL) assessments. However, despite this difference, monitoring is still arguably the best method for determining the effectiveness of stormwater treatment practices. Monitoring of bioretention performance results is needed to inform improvements to design standards and guidance to aid state and local municipalities in the proper selection of bioretention/stormwater controls. This study advocates for instituting fine-scale, “safe-to-fail” design experiments as part of an adaptive management process that is used to advance bioretention design guidance and future applications of monitoring practice(s) that target reduction of pollutants in downstream receiving waterbodies. This innovative approach could result in increased use of bioretention in New England urban environments.
184

La résilience aux inondations à travers les infrastructures vertes et bleues en contexte québécois

Varsi, Santiago 12 1900 (has links)
Le besoin d’agir face aux inondations n’a jamais été aussi pressant. Le Québec a connu dernièrement des épisodes exceptionnels qui rendent à l’évidence la vulnérabilité des communautés face aux inondations, notamment d’un point de vue des infrastructures. Il est temps de réaliser un virage vers des innovations de l’aménagement qui seront davantage inclusives de l’eau. Dans cet esprit, les infrastructures vertes et bleues pourraient offrir une solution complémentaire aux infrastructures plus traditionnelles, étant plus respectueuses de l’environnement ainsi que des personnes, caractérisées par une flexibilité qui vient compenser l’incertitude climatique présentement vécue. Ce mémoire de recherche vise à étudier et cadrer le concept d’infrastructures vertes et bleues afin de proposer un scénario adapté au contexte québécois. L’exercice a permis de proposer des interventions théoriques à deux échelles complémentaires, misant sur les réalisations des acteurs de l’eau ainsi que du laboratoire de recherche dans lequel ce mémoire prend place. / The need to act in the face of floods has never been more crucial. Quebec has recently experienced exceptional episodes that highlight the vulnerability of communities to flooding, particularly from an infrastructure point of view. It is time to shift towards planning innovations that will be more inclusive of water as a resource. In this spirit, green and blue infrastructures could offer a complementary solution to more traditional interventions, being more respectful of the environment as well as people and characterized by a flexibility that can potentially compensate for the climatic uncertainty currently experienced. This thesis aims to study and adapt de concept of green and blue infrastructure to the province of Quebec, by developing a project proposal. This exercise yielded the proposal of theoretical scenarios at two complementary scales, building off local and regional interventions as well as some of the work realized by the research group in which this project takes place.
185

Expectations and reality of sustainable stormwater management : A review of implementation of Nature-Based Solutions - A case study of Southern Stockholm / Förväntningar och verklighet för hållbar dagvattenhantering : En översikt av implementering av naturbaserade lösningar - En fallstudie av Södra Stockholm

Dziubanii, Katarzyna Zofia January 2024 (has links)
The shrinking of permeable areas in favour of urban development is a phenomenon described in both scientific literature and policy documents. Changes in rainfall intensity and frequency following climate change are expected, but predicting the exact magnitude of these changes remains unclear. The uncertainty of what we will have to face in the future and when it will happen causes a blur of activities that may successively influence the mitigation of climate change. This study aims to explore and understand sustainable stormwater management within nature-based solutions (NBS) by reviewing both scientific and grey literature, as well as development plans in a specific area in southern Stockholm. Both risks and benefits of NBS implementation in urban stormwater management have been reviewed and described. Moreover, it is found in the literature that conceptual ambiguities and uncertainties of the NBS concept lead to weaker decision-making and planning processes. The goal of this study was to understand stormwater management recommendations for climate change mitigation, how these recommendations relate to detailed planning documents, what types of solutions are considered and proposed in the planning process, whether there is a link between the NBS and the proposed solutions, and finally, whether spatial analysis can help in the planning process in locating the strengths and weaknesses of the planned construction in flood-prone areas. The results of this study indicates whether the selected detailed development plans follow the recommendations of strategic documents. Detailed planning documents followed the recommendations to a limited extent. Moreover, in terms of spatial analysis, the analysed plans rarely referred to Skyfallsmodell, the model used to represent the flood-risk caused by 100-year rain event. In one of the cases of the early-stage detailed development plan, the new construction area were proposed inside an area with significant risk of flooding. The use of spatial analysis could help urban planners to identify both areas unsuitable for development and locate places suitable for NBS implementation. / Minskningen av genomsläppliga markområden till förmån för stadsutveckling är ett fenomen som beskrivs i både vetenskaplig litteratur och policydokument. Förändringar i nederbördsintensitet och storlek efter klimatförändringar förväntas, men det är fortfarande svårt att förutsäga den exakta storleken på dessa förändringar. Osäkerheten om vad vi kommer att behöva möta i framtiden och när det kommer att hända orsakar en oklarhet kring vilka aktiviteter som kommer att kunna påverka och mildra effekterna av klimatförändringarna. Denna studie syftar till att utforska och förstå hållbar dagvattenhantering genom naturbaserade lösningar (NBS) genom att granska både vetenskaplig och grå litteratur, samt utvecklingsplaner i ett specifikt område i södra Stockholm. Både risker och fördelar med NBS-implementering i urban dagvattenhantering har granskats och beskrivits. Dessutom framgår av litteraturen att begreppsmässiga oklarheter och osäkerheter i NBS-begreppet leder till svagheter i beslutsfattande och planeringsprocesser. Målet med denna studie var att förstå rekommendationer för dagvattenhantering för att mildra klimatförändringar, hur dessa rekommendationer relaterar till detaljerade planeringsdokument, vilka typer av lösningar som övervägs och föreslås i planeringsprocessen, om det finns en koppling mellan NBS och de föreslagna lösningarna, och slutligen - om rumslig analys kan hjälpa till i planeringsprocessen för att lokalisera styrkor och svagheter med den planerade konstruktionen i översvämningsutsatta områden. Resultaten av denna studie indikerar hur de valda detaljutvecklingsplanerna följer rekommendationerna i strategiska dokument. Detaljerade planeringshandlingar följde rekommendationerna i begränsad omfattning. Dessutom, när det gäller rumslig analys, hänvisade de analyserade planerna sällan till Skyfallsmodellen, som används för att representera översvämningsrisken orsakad av 100-årsregn. I ett av fallen med en tidig detaljplanen föreslogs nybyggnadsområdet inom ett område med stor risk för översvämning. Användningen av rumslig analys skulle kunna hjälpa stadsplanerare att identifiera både områden som är olämpliga för utveckling och att lokalisera platser som är lämpliga för implementering av NBS.
186

Comparing bioretention cell and green roof performance in Parma, OH

Sugano, Laura, Sugano 07 May 2018 (has links)
No description available.
187

Integration of ecosystem-based adaptation measures in urban planning : Insights from Copenhagen and Malmö

Baier, Camilla January 2020 (has links)
A key challenge for sustainable urban development is to deal with the effects of climate change. To approach this issue, ecosystem-based adaptation (EbA), i.e. the use of ecosystem services for climate adaptation, has been promoted by both scholars and practitioners. In this context, the thesis addresses two research questions: how EbA is included in strategic climate adaptation planning and how EbA is implemented in practice. To tackle these topics, the study uses a multiple case study design, where the process from strategic planning to its implementation is investigated in two Northern European cities: Copenhagen and Malmö. To collect in-depth data, qualitative methods were used: a document analysis and semi-structured interviews with planning officials were conducted. The findings of the study show that there is a high degree of awareness of the different EbA measures, their potential role to address climate change effects and their co-benefits in climate adaptation plans. However, the practical implementation of the plans was executed only at a project-based scale to address some climate change impacts rather than holistically and on a regional level. The main EbA measure that was used was the expansion and transformation of public green space. The thesis concludes that a more comprehensive approach concerning the use of EbA is needed and further mainstreaming is highly required. / En viktig utmaning för hållbar stadsutveckling är att adressera effekterna av de stundande klimatförändringar. För att ta sig an denna fråga har användningen av ekosystembaserad anpassning (EbA), dvs. användningen av ekosystemtjänster för klimatanpassning, främjats av både forskare och utövare. I detta sammanhang behandlar studien två forskningsfrågor: hur EbA ingår i strategisk klimatanpassningsplanering och hur EbA implementeras i praktiken. Studien innehåller en fallstudie- design, där processen från strategisk planering till dess genomförande undersöks i två nordeuropeiska städer: Köpenhamn och Malmö. För att samla in data användes två kvalitativa metoder: en dokumentanalys och semistrukturerade intervjuer med tjänstepersoner på kommuner. Resultaten från studien visar att det finns en hög grad av medvetenhet om de olika EbA åtgärderna, deras potentiella roll för att hantera klimatförändringseffekter och deras synergier i klimatanpassningsplaner. Det praktiska genomförandet av planerna utfördes endast i en projektbaserad skala för att ta med vissa klimatförändringseffekter snarare än på ett holistiskt vis och på en större regional nivå. Den viktigaste EbA åtgärden som användes var utbyggnaden eller omvandlingen av de offentliga grönytorna. Sammanfattningsvis har studien visat på att det finns behov av ett mer heltäckande tillvägagångssätt och ytterligare integrering beträffande användandet av EbA krävs.
188

Au-delà des services écosystémiques culturels : évaluation des valeurs relationnelles des usagers envers les jardins de rue à Montréal

Doan-Lavoie, Eva 08 1900 (has links)
Les infrastructures vertes urbaines (IVU) fournissent de nombreux bénéfices aux citoyens. L’évaluation des Services Écosystémiques (SE) permet de rendre compte de leur valeur. Le cadre conceptuel des SE valorise la nature de manière instrumentale ou intrinsèque, ce qui est inadapté pour évaluer tous les SE culturels (SEC). La notion de valeur relationnelle permet de combler les lacunes de cette vision dichotomique. Des difficultés demeurent pour opérationnaliser le concept, notamment pour les distinguer des autres valeurs environnementales dû au peu d’études empiriques sur le sujet. S’appuyant sur un cadre théorique de co-construction des SEC, les théories de l’embodiment, puis sur la construction des valeurs relationnelles, cette étude a exploré de manière qualitative les valeurs relationnelles des usagers envers les jardins de rue à Montréal. Puisqu’il s’agit d’une IVU publique en bordure de rue et partagée entre voisins, le rapport à l’espace des usagers est intéressant à étudier. Quatre jardins de rues au profil similaire ont été sélectionnés à cet effet. L’analyse des entrevues semi-dirigées réalisées avec les usagers a démontré leurs valeurs relationnelles envers les jardins de rue. Ceux-ci nourrissent l’identité des usagers, leur fait vivre des expériences valorisées, augmentent leurs capacités et leurs connaissances, accroissent leur sens des responsabilités envers la nature et envers les autres, puis alimentent leur bien-être. Leur rôle social est significatif. L’étude donne des perspectives pour opérationnaliser le concept de valeurs relationnelles en identifiant des indicateurs discursifs de ces valeurs. Les facteurs influençant les valeurs relationnelles des usagers envers les jardins de rue ont été explorés. / Urban green infrastructure (UGI) provides numerous benefits to citizens. Valuation of Ecosystem Services (ES) is a way of accounting for their value. The conceptual framework of ES values nature instrumentally or intrinsically, which is unsuitable for valuing all cultural ES (CES). The notion of relational value can fill the gaps in this dichotomous vision. Difficulties remain in operationalizing the concept, particularly in distinguishing it from other environmental values, due to the paucity of empirical studies on the subject. Drawing on a theoretical framework for the co-construction of CES, embodiment theories, and then on the construction of relational values, this study qualitatively explored users' relational values towards street gardens in Montreal. Since this is a public UGI located on street verge and shared between neighbours, users' relationship to space is interesting to study. Four street gardens with similar profiles were selected for this purpose. Analysis of the semi-structured interviews conducted with users demonstrated their relational values towards street gardens. These gardens nourish users' identity, provide them with valued experiences, increase their skills and knowledge, heighten their sense of responsibility towards nature and others, and fuel their well-being. Their social role is significant. The study provides perspectives for operationalizing the concept of relational value by identifying discursive indicators of these values. Factors influencing users' relational values towards street gardens were explored.
189

Water Fluxes in Soil-Pavement Systems: Integrating Trees, Soils and Infrastructure

de la Mota Daniel, Francisco Javier 31 January 2019 (has links)
In urban areas, trees are often planted in bare soil sidewalk openings (tree pits) which recently are being covered with permeable pavements. Pavements are known to alter soil moisture and temperature, and may have implications for tree growth, root development and depth, drought resilience, and sidewalk lifting. Furthermore, tree pits are often the only unsealed soil surface and are important for water exchange between soil and atmosphere. Therefore, covering tree pits with pavement, even permeable, may have implications for the urban water balance and stormwater management. A better understanding of permeable pavement on tree pavement soil system functioning can inform improved tree pit and street design for greater sustainability of urban environments. We conducted experiments at two sites in Virginia, USA (Mountains and Coastal Plain) with different climate and soil. At each location, we constructed 24 tree pits in a completely randomized experiment with two factors: paved with resin-bound porous-permeable pavement versus unpaved, and planted with Platanus x acerifolia 'Bloodgood' versus unplanted (n = 6). We measured tree stem diameter, root growth and depth, and soil water content and temperature over two growing seasons. We also monitored tree sap flow one week in June 2017 at the Mountains. In addition, we calibrated and validated a soil water flow model, HYDRUS-1D, to predict soil water distribution for different rooting depths, soil textures and pavement thicknesses. Trees in paved tree pits grew larger, with stem diameters 29% (Mountains) and 51% (Coastal Plain) greater. Roots developed faster under pavement, possibly due to the increased soil water content and the extended root growing season (14 more days). Tree transpiration was 33% of unpaved and planted pit water outputs, while it was 64% for paved and planted pits. In June 2016, planted pits had decreased root-zone water storage, while unplanted pits showed increased storage. A water balance of the entire experimental site showed overall decreased soil water storage due to tree water extraction becoming the dominant factor. HYDRUS-1D provided overall best results for model validation at 10 cm depth from soil surface (NSE = 0.447 for planted and paved tree pits), compared to 30- and 60 cm depths. HYDRUS-1D simulations with greater pavement thickness resulted in changes in predicted soil water content at the Coastal Plain, with higher values at 10- and 30-cm depths, but lower values at 60-cm depth. At the Mountains, virtually no difference was observed, possibly due to different soil texture (sandy vs clayey). Tree pits with permeable pavement accelerated tree establishment, but promoted shallower roots, possibly increasing root-pavement conflicts and tree drought susceptibility. Paved tree pits resulted in larger trees, increasing tree transpiration, but reduced soil evaporation compared to unpaved pits. Larger bare soil pits surrounded by permeable pavement might yield the best results to improve urban stormwater retention. Also, HYDRUS 1D was successful at simulating soil water content at 10-cm depth and may be valuable to inform streetscape design and planning. / PHD / Trees in cities are often planted in pavement cutouts (tree pits) that are usually the only available area for water exchange between soil and atmosphere. Tree pits are typically covered with a variety of materials, including permeable pavement. Pavements are known to modify soil water distribution and temperature, affecting tree growth, rooting depth, drought resilience, and sidewalk lifting. A better understanding of this system can inform tree pit and street design for greater sustainability. We constructed 24 tree pits at each of two regions in Virginia, USA (Mountains and Coastal Plain). These tree pits were paved with permeable pavement or unpaved, and planted with London Plane or unplanted. We measured stem diameter, root growth, and soil water content and temperature over two years and tree sap flow for one week in summer (Mountains only). We also used a soil water flow model, HYDRUS-1D, to predict water distribution for different rooting depths, soil textures and pavement thicknesses. After the first growing season trees in pavement were larger, with stem diameters 29% (Mountains) and 51% (Coastal Plain) greater. Roots developed faster under pavement, possibly due to increased soil water content and a 14-day increase in root growing season. Also, in June 2017, tree transpiration was 33% of unpaved-and-planted pit water outputs, and 64% of paved-and-planted pits. In June 2016, root-zone water storage decreased in planted pits but increased in unplanted pits. When considering the entire experimental site, soil water storage decreased, with tree water extraction being the dominant factor. HYDRUS-1D performed better at 10-cm soil depth than at 30- and 60-cm depths. At the Coastal Plain, HYDRUS-1D predicted higher soil water content at 10- and 30-cm depths with increased pavement thickness, but lower values at 60-cm depth. At the Mountains, there was no effect, possibly due to higher clay content. Permeable pavement accelerated tree establishment, but promoted shallower roots, increasing drought susceptibility and risk for root-pavement conflicts. Pavement resulted in larger trees and greater transpiration, but reduced soil evaporation. Larger bare-soil pits surrounded by permeable pavement might optimize stormwater retention.
190

Hybrid Fringes. Discussing contemporary (r-)urban fractal territories: Techno-natural tactics for post-urban systems

Betta, Alessandro 08 October 2020 (has links)
Contemporary debate on the future of urban areas is open and far from finding a convergence point among disciplines. As environmental concerns rise globally and connections between urbanity and ecology are being developed, urban-rural fringes are still an overlooked territory. The thesis proposes a shift in the focus as traditional frameworks have proven to be inadequate to track land-use changes in these hybrid spaces. Starting from selected key concepts, a compelling narrative on hybrid urban-rural fringes is proposed. The thesis benefited from the work done within the Interreg Alpine Space project “Los_Dama!”. This allowed to bridge the gap between research and practice and to directly investigate local planning tools in their adoption process to understand the approach to urban-rural fringes and investigate the role of agriculture. The comparison of the tools and direct fieldwork with local stakeholders supported the understanding of barriers in the implementation of hybrid performative landscapes.

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