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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.
191

Análisis del efecto del arbolado urbano sobre la absorción de material particulado respirable (MP2, 5), mediante el software I - Tree Eco al interior del Parque Ecuador en la ciudad de Concepción

Barra López, Daniel January 2019 (has links)
La realización de esta memoria se encuentra en el marco del proyecto Fondecyt de Iniciación N°1180990 "Construcción social del clima urbano: hacia la calidad y justicia climática en ciudades chilenas". / Memoria para optar al título de Geógrafo / El deterioro en la calidad del aire es uno de los principales problemas ambientales que afectan a las ciudades alrededor del mundo, siendo la polución por material particulado 2,5 (MP2,5) la más peligrosa y mortal para el ser humano. Diversas también han sido las soluciones propuestas para ayudar a mitigar los efectos negativos de la contaminación atmosférica. De estas, una de las que ha tomado mayor fuerza durante el último tiempo corresponde a la utilización de los árboles urbanos para disminuir la contaminación al interior de las ciudades. Mediante el software I-Tree Eco, desarrollado por el Departamento de Agricultura de los Estados Unidos (USDA), se analizaron los efectos que posee el arbolado urbano sobre la interceptación y posterior absorción de MP2,5, al interior de la ciudad de Concepción, Región del Biobío, Chile. A partir de datos de calidad de aire, precipitación y la estructura de los árboles urbanos, el software permite estimar la cantidad de contaminación del aire removida durante un año por los árboles. Para lograr el propósito de la investigación, se utilizaron datos desde el Sistema de Información Nacional de Calidad del Aire (SINCA), mientras que el relleno de datos faltantes de esta base de datos, se realizó por medio del método de imputación de datos individual (SDEM Model). Por otra parte, la base de datos de precipitación se obtuvo desde la Red Agroclimática Nacional (AGROMET). Luego, mediante la fotointerpretación de imágenes satelitales a través de Google Earth, más las capas de levantamiento de espacios verdes, extraídas desde la red CEDEUS y el trabajo en terreno, se identificaron los elementos de la infraestructura verde de mayor relevancia, localizados al interior de la ciudad de Concepción. Junto con ello, se identificó al Parque Ecuador como uno de los espacios más importantes, debido a su tamaño y cercanía con el centro de la ciudad, asimismo, se realizó un inventario completo de los árboles urbanos presentes en su interior, identificando su estructura. Estos datos fueron procesados por el software, obteniendo la eliminación total de la contaminación por MP2,5, su capacidad de almacenamiento y secuestro de carbono, y la emisión total de compuestos orgánicos volátiles biogénicos (COVBs) que poseen los árboles urbanos del parque. Los resultados demuestran que el parque al año eliminó un total de 4,52 Kg de MP2,5, mientras que la tasa de eliminación fue de 0,13 gm-2 por cobertura arbórea; el almacenamiento de carbono fue de 350 toneladas de carbono y su secuestro bruto fue de 3,24 toneladas métricas por año, mientras que las especies del parque anualmente emiten un total de 50,48 Kg de COVBs. / Deterioration of air quality is one of the main environmental problems affecting cities around the world, with particulate matter pollution 2.5 (PM2.5) being the most dangerous and deadly for humans. The proposed solutions to help mitigate the negative effects of air pollution have been diverse; of these, one that has taken greater strength on recent times has been the use of urban trees to reduce pollution inside the cities. This way, through the software I-Tree Eco, developed by the U.S. Department of Agriculture (USDA), the effects of urban trees on the interception and subsequent absorption of PM2.5, inside of Concepción city, Biobío region, Chile were analyzed. Using data of air quality, precipitation and the structure of urban trees, the software allows to estimate the amount of air pollution removed by trees over a year. To achieve the objective of this research, data from the National Air Quality Information System (SINCA) was used, while the filling of missing data was done through the individual data imputation method (SDEM Model). Complete rainfall data was obtained from the National Agroclimatic Network (AGROMET). Then, through photointerpretation of satellite images from Google Earth, plus the layers of green space surveying, extracted from the CEDEUS network and workfield, the most relevant elements of the green infrastructure inside the city of Concepcion were identified. Ecuador Park was identified as one of the most relevant spaces on this city, and a complete inventory of the urban trees that are present inside of it was made, identifying its structure. The data was then processed by the software, obtaining the total elimination of the contamination by PM2.5, their storage capacity and carbon sequestration, and their emission of biogenic volatile organic compounds (BVOCs) that the urban trees of the park have. The results show that the park eliminated a total of 4.52 Kg of MP2.5 per year, while the elimination rate was 0.13 gm-2 for tree coverage; carbon storage was 350 tons of carbon and its gross sequestration was 3.24 metric tons per year, while the park species annually emit a total of 50.48 Kg of BVOCs.
192

How Scale and Scope of Ecosystem Markets Impact Permit Trading: Evidence from Partial Equilibrium Modeling in the Chesapeake Bay Watershed

Natalie R Loduca (9155501) 29 July 2020 (has links)
This study uses the Simplified International Model of agricultural Prices, Land use and the Environment, on a Grid (SIMPLE-G­), a partial equilibrium model of agricultural production, to explore how the scale and scope of environmental quality markets influence farm-level production decisions and market performance. I simulate how permit trading affects producers’ input use decisions, and ultimately pollution emissions, by modifying the supply nest structure of the model to include water quality permits as an additional output from agricultural production. Conservation practices improving water quality may also result in ecosystem co-benefits (e.g., reduced greenhouse gas emissions and habitat provision). Hence, I extend SIMPLE-G to quantify these co-benefits and simulate the effects of allowing conservationist producers to “stack” permits (i.e., to supply multiple permit types for each co-benefit). I find that, overall, permit production increases with the scale and scope of the markets. <a>At the smallest market size</a>—which allows trading only within 8-digit hydrological unit code watersheds—unintended policy implications arise as the stacked markets cause one conservation practice to crowd out the other. Meanwhile, the largest market—which allows trading across the Chesapeake Bay Watershed—produces nitrogen permits more efficiently which may lead to less of the secondary permits in comparison to other market configurations. The results of this study support the Environmental Protection Agency’s urging of the expansion of the scale and scope of ecosystem markets.
193

Perceptions of Problems, Policies, and Politics of a Controversial Pacific State Mosque

Sahakian, Frederick 01 January 2018 (has links)
Despite the existence of land use and environmental protection policies designed to provide guidance on land development, some projects can still be contentious. As the number of Muslims and mosques in the United States are increasing, little is known about the problematic conditions that Muslims may experience when attempting to site a new mosque, community center, or cemetery. The purpose of this study was to develop a deeper understanding about the experiences and perceptions of those involved in the failed siting of a controversial mosque, community center, and cemetery project in a U.S. West Coast state. The multiple streams framework was used to examine the problem, politics, and policy streams that occurred throughout the case. The research question addressed the key elements that led to community protests and the ensuing state lawsuit. A qualitative case study design was used to analyze literature, news reports, government reports, and the loosely-structured interviews of 15 purposefully-selected community stakeholders. The interview data were coded and categorized for thematic analysis. Results indicated that navigating the politics stream was especially difficult for the mosque applicants because they did not anticipate much resistance and were unaware of community members' concerns about water table contamination. Implications for positive social change include providing policy makers with insight into conflict that may arise in the siting of a mosque, community center, or cemetery and potentially reducing conflict between Muslims and non-Muslims.
194

Soil Fertility Status and Degradation of 2, 4, 6-Trinitrotoluene Contaminated Soils

Katseanes, Chelsea Kae 01 March 2014 (has links) (PDF)
Current models for predicting the environmental fate of munitions constituents (MC) in soils are based mostly on chemical distribution parameters and neglect the larger considerations of other soil parameters. We are working towards a new approach based on the whole soil activity for predicting the long-term residence time and fate of MC in soils with connection to agronomic soil fertility concepts. These relationships are demonstrated by correlating experiments involving full physical and chemical characterization of eight taxonomically distinct soils, with batch reactor studies determining MC degradation potential. Soils were incubated in a slurry for 10 days in a closed reactor system with temperature, pH, and Eh readings recorded every 24 h. Air and slurry samples were taken eight times within the 168 h incubation period. Carbon dioxide, TNT, and nutrient solution concentrations were assessed to obtain a full picture of soil chemistry changes associated with microbial activity in response to additions of TNT. Multivariate analysis was used to determine the main factors impacting degradation rate. Principle Components Analysis (PCA) statistically classified the soils based on the variance of their soil property data. Partial Least Squares Analysis (PLS) showed that TNT degradation was possibly correlated with soil fertility characteristics. Although this is an exploratory study, results show promise in moving towards a more effective way of predicting TNT environmental fate in soils.
195

Ekosystemtjänster från anlagda och restaurerade våtmarker : Och hur de kan bidra till att de svenska miljökvalitetsmålen uppnås / Ecosystem services from constructed and restored wetlands : And how they can contribute to achieving the Swedish environmental quality objectives

Hjerpe, Felicia, Olsson, Alexandra January 2022 (has links)
Under det senaste seklet har svensk våtmarksareal minskat med en fjärdedel, vilket motsvarar 2,7 miljoner hektar. Detta till följd av ett industrialiserat samhälle med ett starkt intresse i utbyggnad av jordbruk, skogsbruk och vattenkraft. Exploateringen av svensk våtmark har medfört att många av de betydelsefulla ekosystemtjänster våtmarker bidrar med har upphört. Idag är det på grund av denna förlust aktuellt att anlägga och restaurera våtmark, bland annat i syfte att erhålla en eller flera av dessa ekosystemtjänster. Syftet med denna rapport är att undersöka vilken miljö- och klimatpåverkan anlagda och restaurerade våtmarker medför samt huruvida de kan bidra till att de svenska miljökvalitetsmålen uppnås. Genom en omfattande litteraturstudie insamlades data som legat till grund för den bedömning som gett rapportens resultat. Resultatet visade på olika nivåer av påverkan på miljö och klimat från bland annat ekosystemtjänsterna vattenrening, biologisk mångfald och klimatreglering, med slutsatsen att den sammanlagda påverkan främst är positiv. Effekterna av ekosystemtjänsterna bedömdes även påverka företrädesvis sex av de sexton miljökvalitetsmålen för vilka en noggrannare bedömning genomfördes, med slutsatsen att anläggning och restaurering av våtmark har en främst positiv påverkan på fem av dessa mål. / During the last century, the Swedish wetland area has decreased by a quarter, equal to 2.7 million hectares, due to an industrialized society with a strong interest in further expansion of agriculture, forestry, and hydropower. The exploitation of Swedish wetlands has resulted in the cessation of many essential ecosystem services to which wetlands contribute. Due to this loss of wetland area, it is now relevant to construct and restore wetlands to obtain one or more ecosystem services. The purpose of this report is to investigate the extent to which these ecosystem services can be acquired from constructed and restored wetlands and whether these can contribute to achieving the Swedish environmental quality objectives. Data was collected through an extensive literature study which formed the basis for the assessment that led to the report's result. The result showed different levels of impact on the environment and climate from the ecosystem services water purification, biodiversity, and climate regulation, with the conclusion that the total effect is mainly positive. The effects of the ecosystem services were also assessed to affect primarily six of the sixteen environmental quality objectives for which a more accurate assessment was carried out, with the conclusion that construction and restoration of wetlands has a primarily positive effect on five of these objectives.
196

Övergödning av Mälaren : Betydelsen av antalet beviljade dispenser av stallgödselspridning vid Sagån

Vinberg, Ulrika January 2010 (has links)
<p>Eutrophication was recognized in the early 1900's and results in severe algal blooms, increased biomass production and eventually leads to an altered ecosystem. In Mälardalen we find the most eutrophic lakes. Most of the applied phosphorus and nitrogen into seas and oceans comes from agriculture, and the nutrients losses are affected by local weather conditions and soil type. Guidelines for storage and distribution of manure were introduced in the 80s, and the rules were strengthened January 1, 2010. Localities and previous county administrations can whether there are special reasons, grant an exemption for manure application during winter-periods despite the current ban.</p><p>In this essay I have examined how many exemptions of manure application that has been granted at the Sagån river, and what implications it has for the eutrophication of Lake Mälaren. Sagån’s catchment area extends through Enköping, Sala, Heby, Västerås and Uppsala. Since 2000, 23 waivers of manure application have been granted, most of these deviations have occurred on snow-covered ground or when the weather change considerably. This means that much of the nutriment in the manure went down to the nearby water when the snow melted. Computations were made In order to find out how much phosphorus was spread each time. The conclusion is that the pig manure contains significantly more phosphorus, meaning greater phosphorus losses. However, these calculations are only estimates.</p><p>Several farmers were contacted to find out what they think about the regulation of the management and application of manure. They believe that the new legislation does not pose a problem for them. But farmers with small distribution areas in relation to the number of animals could have some problems.</p>
197

A critique of the CEQA process in evaluating land use impacts on a transit system : the Natomas Village Center case study

Cruz, Annie Kathleen Freeland January 2003 (has links)
This study examines how well California's Environmental Quality Act (CEQA) evaluates land use redesignations on transit projects, in particular light rail. A case study of the Natomas Village Center, a proposed project in Sacramento, California, is analyzed in relation to its Environmental Impact Report (EIR) and the CEQA process.Specifically, the focus of the investigation is on assessing the impacts of land use changes on the Downtown-Natomas-Airport light rail alignment. The CEQA methodology and how it is employed are critiqued for their effectiveness in documenting and mitigating the environmental impacts on light rail transit adjacent to the Natomas Village Center. / Department of Urban Planning
198

Dimensionering och optimering av ett solcellssystem för en industribyggnad i Mellansverige : En simuleringsstudie

Östlund, Christine January 2019 (has links)
Vid omställningen till förnybara energisystem är solkraften som energikälla ett möjligt alternativ, för att uppnå klimat och energimålet med 100% förnybar energiproduktion år 2040. Detta är något regeringen eftersträvar genom infört bidrag i form av subventioner och skattereduktion vid installation av solceller. I denna fallstudie undersöks vilken effekt två olika solcellssystem har för en industribyggnad i Mellansverige, där studien tar hänsyn till ekonomisk-, teknisk- och klimatrelaterade aspekter. Systemen dimensioneras i strävan av optimala förhållanden samt av byggnadens begränsningar, med kostnadsförslag från en lokal återförsäljare få en bild av om återbetalningstiden är motiverande i frågan. Den lokala klimatpåverkan analyseras med växthusgasutsläpp i fokus, detta genom resultat av litteraturstudie. Dimensioneringen av solcellssystemen baseras på empiriskt material av studieobjektet och simuleras i programmet Winsun PV. Studien resulterade i två storlekar på system med tillhörande kostnadsförslag som ligger till grund för återbetalningstiden. System fall 1 dimensionerades i syfte att hålla den nominella systemeffektens storlek till 255 kWp, detta för att undgå extra energiskatt. Systemet gav ett årligt utbyte av 228 MWh/år som gav återbetalningstid mellan 18 – 22,5 år. Systemet simulerades med optimal lutningsvinkel av 39° i 15° azimutriktning av modulerna. System fall 2 dimensionerades till 1200 kWp i syfte att täcka effektivt användbar takyta, med årligt utbyte på 886 MWh/år och återbetalningstiden blev mellan 22,5 – 25,1 år. Modulerna simulerades med takets lutning ±4,7° i -15° azimutriktning. För att solceller ska ge ett mer lönsamt utbyte i högre latituder krävs en vidare effektivitetsutveckling för solcellstekniken samt ett förlängt investeringsstöd från Länsstyrelsen för framtida installationer. Om solcellssystemet ger en positiv inverkan på det ekologiska fotavtrycket beror av vart solcellen är tillverkad samt vilken elmix som byts ut mot den producerade solenergin. / When converting to renewable energy systems, solar power as an energy source is a potential option; in order to achieve the climate and energy goal with 100% renewable energy production in year 2040. This is something the government try to achieve by making installation of solar cells more attractive through allowances such as subventions and tax reduction. The aim of this study was to analyze the effect of solar cell system on an industrial building in the midst of Sweden, in regard of economical-, technical- and climate related points of view. This was performed by replacing purchased electricity with locally produced electricity, where optimal circumstances for the solar power systems and the limits of the building has been taken into consideration during the dimensioning. With cost suggestions from a local authorized dealer the magnitude of the pay off time as a motivating factor was estimated. The local climate impact will be investigated through a litterature study, focusing on green house gas emissions. The dimensioning of the solar cell systems were based on empirical input from measurements in combination with documented data regarding the industrial building and simulated in the program Winsun PV. The study resulted in two different-sized systems with cost sheets that formed the basis for the calculated pay off time. System case 1 was dimensioned to keep the size of the nominal system effect to 255 kWp, this to avoid extra energy tax. The system gave an annual exchange of 228 MWh / year which gave the repayment period between 18 - 23 years. The system was simulated with an optimum angle of 39 ° in 15 ° azimuth direction of the modules. System case 2 was dimensioned to 1200 kWp in order to cover the effective usable surface of the roof, the system gave an annual exchange of 886 MWh / year and the repayment period was 22.5 - 25.1 years. The modules were simulated with the roof slope ± 4.7 ° in -15 ° azimuth direction. A further efficiency development for solar cell technology is required as well as an extended investment support from the County Administrative Board, to provide a more profitable exchange of solar cell systems in higher latitudes. If the solar cell system has a positive effect on the ecological footprint depends on where the solar cell is made and which electrical mix replaced by the produced solar energy.
199

Análise espacial e desigualdade ambiental no município de São Paulo / Spatial analysis and environmental inequality in São Paulo city

Morato, Rubia Gomes 25 November 2008 (has links)
O objetivo desta pesquisa é estudar a análise espacial da desigualdade ambiental no município de São Paulo/SP. A desigualdade ambiental é o princípio pelo qual, grupos de pessoas sejam étnicos, raciais ou de classe suporte uma parcela desproporcional das conseqüências ambientais negativas das operações econômicas, de políticas e programas federais, estaduais e locais, bem como resultantes da ausência ou omissão de tais políticas. Os dados utilizados para análise são o Censo 2000, realizado pelo IBGE, uma imagem de satélite Landsat ETM+, a carta geotécnica do município de São Paulo, produzida pelo IPT e o levantamento de áreas contaminadas realizado pela Cetesb. São consideradas as condições de abastecimento de água, de esgotamento sanitário, de coleta de lixo, a arborização urbana, a ocorrência de inundações e/ou escorregamentos e a presença de reservatórios de retenção das águas pluviais (piscinões) e áreas contaminadas. Para a análise e integração dos dados é utilizado um Sistema de Informação Geográfica com funções de processamento de imagens. / The purpose of this work consists of studying the spatial analysis of the environmental inequality in São Paulo city. Environmental inequality is the principle that a specific social group (eg. ethical, racial or economic) is disproportionately affected by environmental hazards. In this study we used: 2000 Census data (released by IBGE); Landsat ETM+ image of bands 3 and 4; a geotechnical map of São Paulo (IPT) and a list of contaminated point sources carried out by Cetesb. Urban infrastructure facilities such as water supply coverage; sewerage system; garbage collection; urban green area; landslides and flood occurrences; presence of piscinões and contaminated area were employed. The analysis of these data was undertaken using a Geographic Information System (GIS) integrated with Remote Sensing image processing.
200

Padrões de ocupação do solo e microclimas urbanos na região de clima tropical continental. / Urban occupation patterns and microclimates in the brazilian continental tropical region

Duarte, Denise Helena Silva 05 December 2000 (has links)
O objeto deste trabalho são os microclimas urbanos nas cidades brasileiras na região de Clima Tropical Continental. Partindo do princípio que há uma correlação entre microclimas urbanos e ocupação do solo, o objetivo é medir numericamente a correlação entre a temperatura do ar e algumas variáveis familiares ao planejamento, e que podem ser regulamentadas pela legislação municipal, a fim de orientar as medidas necessárias para amenizar o rigor climático nas cidades da região. Faz-se uma descrição qualitativa e quantitativa das variáveis urbanísticas envolvidas, bem como medições de temperatura e umidade do ar em diferentes estações e horários. Os resultados mostram que as variáveis taxa de ocupação e coeficiente de aproveitamento mantém correlação positiva com a temperatura do ar, e refletem uma maior influência da densidade construída sobre o período noturno, o que concorda com a teoria existente. Já com as variáveis arborização e água a correlação foi negativa em relação à temperatura do ar, em todos os horários. Ao final propõe-se um índice em função das variáveis urbanísticas utilizadas, visando subsidiar futuros trabalhos na determinação da proporção ideal entre densidade construída, arborização e água. / The subject of this thesis is the urban microclimate in cities of the Brazilian Continental Tropical Region. According to the principle that there is a correlation between urban microclimates and urban occupation, the objective is to numerically measure the correlation between air temperature and variables which are familiar to urban planning strategies. These variables can be controlled by municipal regulations, aiming to guide the procedures to ameliorate the urban harsh climate in that region. Qualitative and quantitative descriptions of the urban variables are made, as air temperature and humidity measurements registered along the day for the two main seasons. The results show that with variables related to building density, the correlation was positive when referred to air temperature, and reflected the greater influence of building density at night, what is in accord with the existing theory. On the other hand, using trees and water, the correlation was negative, when related to air temperature, in all periods. At the end, this work suggests an index using urban variables, aiming to support future studies in determining the ideal proportion among building density, trees and water in urban environments.

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