Dissertations / Theses on the topic 'Pollution pattern'
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1
Tegegn, Ferezer. "Physico-chemical pollution pattern along Akaki River basin, Addis Ababa, Ethiopia." Thesis, Stockholms universitet, Institutionen för naturgeografi och kvartärgeologi (INK), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-80460.
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The present study focuses on the analysis of physico-chemical parameters: electrical conductivity, nitrate and phosphate in the Akaki River basin of Addis Ababa, Ethiopia. These secondary water quality parameters were obtained from two different sources: the surface water quality data both for Little and Great Akaki were retrieved from Addis Ababa Environmental Protection Agency (AAEPA). Whereas, the groundwater quality data for four water wells were obtained from Addis Ababa Water and Sewerage Authority (AAWSA). These water quality parameters have been determined in order to assess the pollution levels of Akaki River basin. The values of the parameters have been evaluated with respect to the maximum acceptable standard level of WHO (World Health Organization) for surface and drinking water. The outcome of the study observed absence of spatial and temporal pattern both on surface and groundwater but displayed a huge variation. The result also showed increasing concentration and variation of all parameters inside and outside the city of Addis Ababa with increasing industrialization and urbanization. Comparison also showed that the little Akaki is highly polluted as compared to Great Akaki River. The ground water chemistry also showed a high phosphate load in all of the productive wells. On the contrary, all the wells displayed nitrate level below WHO standard and they are free from Nitrate. KEY WORDS: Addis Ababa, Ethiopia, Physico-chemical, Little and Great Akaki, AAEPA, AAWSA, Spatial, temporal.
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Purkayastha, Kanan K. "Pattern recognition and an OH reactivity study of urban air pollution." Thesis, University of Bristol, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.683909.
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Pattern recognition focuses on the recognition of pattern and regularities in data. In urban air pollution studies such as the study of the relationship between air pollutant concentration and meteorology data or atmospheric photochemistry, such as hydroxyl molecule loss in the atmosphere, pattern recognition is pertinent. This thesis presents various case studies where emission potential to atmosphere, concentration pattern in an air basin, extreme event pattern on a local or regional scale, patterns of the relationship between meteorological parameters and chemical parameter and atmospheric chemical loss processes have been explored. The thesis presents some new approaches to studying urban air pollution. The first study is a landfill gas emission potential study, where the composite signal has been analysed. The study proposes a new Monte Carlo permutation scheme to capture the composite landfill gas emission potential to the atmosphere. It also compares the new method with the traditional Fisher g statistics method. The second study reviews the existing methods for identifying extreme events of particulate matter on a local and regional scale and develops a new method based upon medcouple calculations of dispersion of data. This study also informs the relationship between local meteorology and extreme events using a new mathematical approach. The third study involves different pattern recognition techniques such as self organising maps, hierarchical and non-hierarchical clustering techniques, the receiver operating characte11stic curve method and a multivariate statistical approach to explore the pattern of air pollution on a regional scale. The fourth study involves applying soft modelling approaches such as block similarity measures, partial least square and principal component regression techniques to explore the relationship between meteorology and urban air pollution. This study applies a new kind of instrument known as an AQ mesh. So appropriate calibration approaches for studying these data have been followed. The fifth study is the measurement of total OH reactivity in a subtropical climatic region in the autumn season. Non-methane volatile organic carbon and different trace species contribution to OH reactivity have been assessed. This study involves the development of an instrument to generate the OH radical in a laboratory environment and kinetic study of the OH radical with volatile organic carbons and trace species in ambient air. An attempt has also been made in this study to calculate the potential "Criegee intermediate" by the ozonolysis of identified alkenes in the ambient air.
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Hantsch, Nichole M. "Pattern and process of watershed nutrient dynamics in South Central New York." Diss., Online access via UMI:, 2008.
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Bellchamber, Sara B. "Simulating the effects of riparian zone delineation and management practices on landscape pattern and timber production." Diss., Columbia, Mo. : University of Missouri-Columbia, 2004. http://hdl.handle.net/10355/4106.
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Thesis (M.S.) University of Missouri-Columbia, 2004.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (June 29, 2006) Vita. Includes bibliographical references.
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Shrestha, Samata. "IMPACT OF NEIGHBORHOOD MORPHOLOGY ON AIR POLLUTION DISPERSION PATTERNS DUE TO UNPLANNED BUILDING DEMOLITION: A PARAMETRIC STUDY." Kent State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=kent155654365109521.
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Philander, Lorraine. "The effect of an argumentation-based instructional approach on Grade 3 learners' understanding of river pollution." Thesis, University of the Western Cape, 2012. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_7227_1381213860.
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The research reported in this paper involves the use of dialogical argumentation in scientific context with 7-9 year olds as part of teaching and learning in primary classrooms. To develop an understanding of scientific concepts, four suitable collaborative activities on river pollution were used as a stimulus to effectively engage learners in scientific reasoning and use evidence for decision-making through cognitive harmonization. The research, involved four groups of five children each. Data were collected through analysis of children&rsquo
s Water Pollution Questionnaire (WPQ), classroom observation, documentation of field notes, conversations and focus group interviews. The study found that all groups were able to engage in the activities to some extent, but that good quality argumentation develops when children are familiar with working in this manner. This study sought to investigate the opportunities, possibilities and challenges associated with a dialogical argumentation teaching and learning approach in a primary school science class A mapping technique was used to analyze the children&rsquo
s discussions and identify the quality of their different &ldquo
levels&rdquo
of argument. This study confirmed that an argumentation based instruction was an effective way of enhancing learners&rsquo
understanding of river pollution. The learners&rsquo
listening skills improved tremendously and they were actively involve during discussions and provided claims with valid grounds or reasons. They were also very enthusiastic and challenged each other&rsquo
s claims during these argumentation lessons, but most of all was the enjoyment that was visible on their young faces. Further research needs to be carried out over a longer period to determine the effectiveness of an argumentation based instruction.
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Magerman, Ruben Clive. "Effects of an argumentation-based instruction on grade 10 learners' understanding of the causes of pollution at a river site." Thesis, University of the Western Cape, 2011. http://hdl.handle.net/11394/1777.
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Magister Scientiae - MScThis study was based on the Science and Indigenous Knowledge Systems Project (SIKSP) at the School of Science and Mathematics Education, University of the Western Cape. The project seeks to enhance educators' understanding of and ability to implement a Science-IKS curriculum (Ogunniyi, 2007) through using the theoretical framework of argumentation (Toulmin Argument Pattern) to the extent that learners would value the significance of both worldviews. This study sought to find the effects of an Argumentation-Based Instruction on grade 10 learners' understanding of the causes of pollution at a river site. Since the integration of Science and IKS are envisaged by Curriculum 2005 (C2005), two theoretical argumentation constructs have been used namely, Toulmin's (1958) Argumentation Pattern (TAP) and Ogunniyi's (1995) Contiguity Argumentation Theory (CAT).
South Africa
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Henshaw, Stephen John. "Trends and patterns in urban air pollution in the UK." Thesis, University of Bristol, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.509769.
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Al-Mutawa, Ayesha Ibrahim. "The influence of the meteorological conditions on air pollution levels in Emirate of Dubai, United Arab Emirates." Thesis, University of Liverpool, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366431.
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Forselius, Ellen. "Spatial patterns of pollution associated with creosote treated poles in Mälardalen." Thesis, Stockholms universitet, Institutionen för naturgeografi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-120583.
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Creosote is a product name given to a mixture of several hundred compounds, which is often used to protect wooden poles from rot and insect damage, however it has also been linked to causing cancer in humans. Alternative materials for power poles include concrete, steel, composite and non-treated wooden poles. This report looks at Mälarenergi Elnät ABs 17,000 creosote coated poles and their patterns of pollution. GIS analyses in ArcGIS were used to evaluate which creosote poles are most critical to replace by implementing a system of "penalty points" based on the spatial distribution of the poles. 15 of the creosote poles were selected for a field study to investigate how much creosote is leaked to the ground.1,000 of the power poles were assigned penalty points of 10 or higher which could be a starting point in pole replacement, although the penalty points system could be used in many different ways for this purpose. Of the 15 power poles investigated during the field work, 5 showed higher leakage than recommended by Naturvårdsverkets guidelines for sensitive ground use. These 15 poles only make up 0,1% of Mälarenergi Elnät ABs total creosote coated poles, but the results are considered alarming enough to at least merit further studies of the creosote leakage.
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Hall, Kimberlee K., Brian G. Evanshen, Kurt J. Maier, and Phillip R. Scheuerman. "Using Multivariate Statistics to Identify Patterns Association Land Use to Fecal Pollution Sources.Similar Creeks in Northeast Tennessee to Identify Patterns Associating Land Use to Fecal Pollution Sources." Digital Commons @ East Tennessee State University, 2011. https://dc.etsu.edu/etsu-works/2948.
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Long, Xuezhu. "Particulate air pollution in central London : characterisation, temporal patterns and source apportionment." Thesis, University College London (University of London), 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247431.
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Ba-Akdah, Mohammad Abdulaziz Salim. "Patterns in the uptake, release, distribution, and transfer of petroleum hydrocarbons in marine organisms." Thesis, Heriot-Watt University, 1996. http://hdl.handle.net/10399/1304.
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Monthe, Luc Arthur. "Etude des équations aux dérivées partielles hyperboliques application aux équations de Saint-Venant." Rouen, 1997. http://www.theses.fr/1997ROUES074.
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Dans ce travail, nous avons adapté une méthode de volumes finis aux équations de Saint-Venant avec termes sources, dans des configurations monodimensionnelles et bidimensionnelles complexes. Ces équations représentent les écoulements de l'eau peu profonde, consécutifs par exemple a une rupture de barrage. Pour la partie hyperbolique des équations, le schéma de Roe, solveur approché de Riemann, est introduit, et amélioré par une modification entropique, afin de prendre en compte les configurations particulières, telles que l'écoulement sur fond sec. Une extension à l'ordre deux de ce schéma a été réalisée, soit par la méthode de limitation de flux, soit par la méthode MUSCL en espace et Runge-Kutta 2 en temps. Une analyse de stabilité numérique non linéaire a été menée ; cela a permis la justification et la prédiction de limitations sur la condition CFL, confirmées par les expériences numériques. D'autre part, on introduit un schéma fractionné pour la prise en compte du terme source. La stabilité et la convergence du schéma vers la solution entropique sont prouvées dans le cas scalaire. Dans le cas de problèmes bidimensionnels, et afin de traiter correctement les termes de diffusion, des schémas conçus et analysés récemment ont été appliqués. Il s'agit d'un schéma à neuf points (VF9) dans le cas de maillages structurés, et d'un schéma à quatre points (VF4) dans le cas de maillages non structurés. En outre, une technique d'adaptation de maillage basée sur la méthode des ressorts a été utilisée avec succès, dans le cas de maillages structurés, afin de capturer avec plus de précisions les ondes de chocs et de détente. Enfin, on présente une méthode originale d'optimisation, les algorithmes génétiques (GAS), faisant le lien entre la méthode des volumes finis introduite et l'identification de paramètres physiques. Les expériences numériques réalisées, entre autres pour la propagation de polluants dans des domaines à géométrie complexe, ont confirmé les performances de ces méthodes.
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Wade, Katherine Signs. "A Descriptive Analysis of Temporal Patterns of Air Pollution in Atlanta, GA and an Assessment of Measurement Error in Air Pollution Monitoring Networks in Atlanta, GA." Thesis, Available online, Georgia Institute of Technology, 2005, 2005. http://etd.gatech.edu/theses/available/etd-08252005-141752/.
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Thesis (M. S.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2006.Mulholland, James, Committee Chair ; Russell, Armistead, Committee Member ; Tolbert, Paige, Committee Member.
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Saraswat, Arvind. "Air pollution in New Delhi, India : spatial and temporal patterns of ambient concentrations and human exposure." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/56224.
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Urban air pollution is a major health and environmental concern worldwide, and the levels are extremely high in New Delhi, India. This research is focused on the spatial and temporal variability of air pollutant concentrations and its implications for population exposure in New Delhi. Since traffic is considered a significant source of air pollutants in urban environments, robust and multiple linear regression models were used to understand the impact of local traffic flow on ambient concentrations of PM₂.₅, CO, NO and NO₂ at a busy intersection. To elicit the spatiotemporal variability of PM₂.₅ and its constituents (black carbon and ultrafine particles), land use regression (LUR) models were developed. Separate morning and afternoon models were developed using 136 hours (39 sites), 112 hours (26 sites) and 147 hours (39 sites) of PM₂.₅, BC and UFPN data, respectively. Finally, to understand how spatiotemporal variations in PM₂.₅ concentrations impact population exposure, a probabilistic simulation framework was developed to integrate the PM₂.₅ LUR models with time-activity data obtained from a field survey. Regression models explained about 50–80% variability in hourly pollutant concentrations and localized traffic flow explained up to 19% of variability on that scale. Auto-rickshaw and truck flow had a higher influence on NO₂ and PM₂.₅ concentrations, respectively. Independent variables in the LUR models included population density, distance from major roads, and major and minor road lengths in buffers of different radii; measurements from a fixed continuous monitoring site were also used as independent variables in the PM₂.₅ and BC models. The temporal term explained most of the variability (63–77%) in PM₂.₅ and BC models compared to spatial variables (4–16%). Exposure simulations indicate that the estimated annual average PM₂.₅ exposure (109 µg m-³) was high compared to North American or European cities. PM₂.₅ exposures were highest during the winter months (~200 µg m-³) compared to the summer months (~50 µg m-³). Ignoring mobility (i.e. exposure during transport or at work/school locations), as is generally assumed in epidemiologic studies of long-term exposure, underestimated PM₂.₅ population exposure by about 11%.Science, Faculty of
Resources, Environment and Sustainability (IRES), Institute for
Graduate
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Gurram, Sashikanth. "Understanding the Linkages between Urban Transportation Design and Population Exposure to Traffic-Related Air Pollution: Application of an Integrated Transportation and Air Pollution Modeling Framework to Tampa, FL." Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/7030.
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Rapid and unplanned urbanization has ushered in a variety of public health challenges, including exposure to traffic pollution and greater dependence on automobiles. Moreover, vulnerable population groups often bear the brunt of negative outcomes and are subject to disproportionate exposure and health effects. This makes it imperative for urban transportation engineers, land use planners, and public health professionals to work synergistically to understand both the relationship between urban design and population exposure to traffic pollution, and its social distribution. Researchers have started to pay close attention to this connection, mainly by conducting observational studies on the relationship between transportation, urban form, and air quality. However, research on this topic is still nascent. Further, most studies do not predict exposures under alternative urban design scenarios. Hence, to understand the relationship between urban design and population exposures, there is a need to build and apply integrated modeling tools that can predict exposures under alternative urban design scenarios.
Within this context, the overarching goal of this dissertation is to understand how the transportation infrastructure of cities can be designed for improved urban air quality and mitigation of population exposure to traffic pollution. The study area is Hillsborough County, Florida, a sprawling region with limited transit availability and a diverse population along with a mix of urban, suburban, and rural areas. The rank of the county for sprawl and congestion metrics (i.e., yearly delay and travel time index) fall in the mid-range in comparison with other US urban regions. Thus, the study area may be representative of other US urban regions with medium sprawl and above-average congestion levels. Oxides of nitrogen (NOx), a surrogate for traffic pollution, is the focus pollutant. The Health Effects Institute’s report on traffic-related air pollution identifies NOx as a potential surrogate due to its relative ease of measurement and the abundance of epidemiologic studies that characterize exposures to NOx.
Because exposures are dependent on the spatial and temporal distributions of both people and pollution, this study first sought to understand the importance of activity and travel patterns of individuals for exposure estimation. To estimate exposures, the 2009 National Household Travel Survey (NHTS) data containing daily individual activity records, ArcGIS-estimated shortest-time travel route profiles, and the annual-average diurnal cycle of NOx derived from hourly CALPUFF dispersion model results from 2002, were combined. Two exposure measures were estimated: activity-based exposure that considers the daily activity and travel patterns of individuals, and residence-based exposure that considers only the pollutant concentrations at the residences. Exposure estimation without inclusion of activity and travel patterns was found to slightly underestimate activity-based exposures on average. Additionally, disproportionately-high exposures were found for blacks, Hispanics, below poverty groups, urban residents, and people whose daily travel time is greater than one hour. Finally, urbanicity and travel time variables were found to be the strongest predictors of daily exposure.
Following this, a modeling framework was developed to predict population exposure by integrating activity-based travel demand modeling (DaySim), dynamic traffic assignment simulation (MATSim), mobile-source emission estimation (EPA MOVES), and pollutant dispersion modeling (R LINE). This modeling framework was used to predict daily population and subgroup exposures by estimating the high-resolution spatial and temporal distributions of both pollution and individual activities for the year 2010. Persistent exposure inequalities were found at the population-level; blacks, Hispanics, active age groups (19-65 years), below-poverty and middle-income groups, urban residents, and individuals with daily travel times above one hour had higher estimated exposures than the population mean. These inequalities for blacks, Hispanics, and below-poverty non-white groups worsened at higher exposure levels. Use of low-resolution activity and pollution data as opposed to high-resolution data led to underestimation of exposures (by 10% on average).
Finally, the integrated modeling framework was employed to understand the relationship between urban transportation and land use design, air quality, and population exposure. Three scenarios that are based on a combination of diesel-bus transit services and residential distribution were simulated. Specifically, the low-transit scenario used the 2040 base residential distribution and the 2010 bus services. The enhanced-transit scenario applied the 2040 bus services proposed for the county instead. The compact-growth scenario added an increase of residential density to this latter scenario. Specifically, about 37% of total households were redistributed from locations with low accessibility to jobs and transit to locations near employment and bus stops. Results indicate slight higher non-car travel mode shares in the enhanced-transit and compact-growth scenarios compared to the low-transit scenario (with a 7.1% increase for walking, 0.2% for bicycle, and 1.8% for transit for the compact-growth scenario versus the low-transit scenario). The enhanced-transit scenario resulted in slightly lower daily total travel distances and times compared with the low-transit scenario, but daily total emissions and winter mean concentration of NOx were higher, i.e., the increase in bus transit services did not induce sufficient shifts in travel mode to overcome the concomitant increase in diesel-bus emissions. The compact-growth scenario resulted in lower daily total travel distance (9%) and travel time (2.1%) and daily total emissions of NOx (11%) and its winter mean concentration (9%), compared with both the low-transit and enhanced-transit scenarios. Although the compact-growth scenario improved the air quality of the region on average, daily population mean exposure was higher compared with both the low-transit (29%) and enhanced-transit scenarios (25%). This is largely due to the redistribution of population to urban core locations that had higher pollutant levels. Overall, neither the bus-transit improvements nor residential compaction strategies alone were sufficient to mitigate population exposures. Combining them with transit that services both origins and destinations, uses clean fuel technologies, and separates major roadways from dense residential pockets may be needed for greater exposure reductions.
Overall, this dissertation has implications for population exposure to traffic pollution and public health through transportation and land use interventions. Results presented here may be applicable to other study regions that have similar composite sprawl scores as the Tampa Bay area. Future studies should exploit spatially-and temporally-resolved data on human activities and travel, vehicular activities, and air quality for better characterization of population exposure. Engineers and planners should pay greater attention to integrated land use and transport planning; lone, disjointed, and ill-planned design interventions may exacerbate population exposure to air pollution. The integrated modeling framework presented here may be applied in a wide variety of urban contexts to further explore the nexus between travel demand, air quality, and exposures. However, before such an exercise is undertaken, a preliminary analysis should be conducted to assess the transferability of the framework. Policies that could be studied include mixed land use design, urban compaction with controlled sociodemographic distributions (to assess exposure inequality), and inclusion of additional types of transit and fuel technologies.
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Mohammed, Nuredin Ibrahim. "Daily changes and short-term exposure patterns in time series studies of air pollution and acute health effects." Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/6658/.
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This thesis investigated the effects of daily changes in exposure (delta) and short-term exposure patterns on the relationship between air pollution and health in time series studies. Using data from London and Hong Kong, delta was defined as the difference in particulate matter (PM10) concentration between successive days. Short-term exposure pattern series were defined based on number of peaks in PM10 within rolling weekly blocks. The mathematical equivalence of identifiable models for delta with conventional distributed lag model was derived and alternative model specifications were proposed. Measurement error and missing data exhibited more impact on delta than the absolute metrics in simulation studies. Evidence of association for delta PM10 with mortality was found only in Hong Kong which attenuated towards the null with more rigorous adjustment for weather. The pattern analysis approach hypothesized, in addition to amount (dose) and duration of exposure, epidemiological studies ought to take patterns of exposure into account. However, convincing evidence was not found for the effect of short-term exposure patterns on mortality risk estimates both in London and Hong Kong. Refining the definition of exposure patterns and methodological improvements including analysing data from multiple cities are highly recommended in related studies in the future.
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Palm, Britta. "Pesticide use in rice cultivation in Tarapoto, Peru : usage patterns and pesticide residues in water sources /." Uppsala : Swedish University of Agricultural Sciences, Department of Environmental Assessment, 2007. http://epsilon.slu.se/10587693.pdf.
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Truluck, Timothy Francis. "Hospital admission patterns of childhood respiratory illness in Cape Town and their association with air pollution and meteorological factors." Master's thesis, University of Cape Town, 1993. http://hdl.handle.net/11427/17402.
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Bibliography: pages 103-119.The aims of this study were (a) to examine the profile of hospital admissions for selected respiratory illnesses for two major hospitals in Cape Town, and (b) to analyse the association of such admissions with air pollution indicators and meteorological variables. The first part of the study investigated the admission patterns of coloured and African children under twelve years of age who were diagnosed as suffering from asthma or acute respiratory infections at two major teaching hospitals in Cape Town. Computerized hospital admission records covering the years 1988-1990 from the overnight holding wards of the Red Cross War Memorial Children's Hospital and Tygerberg Hospital were used to determine patterns with respect to diagnosis, gender, race, age and date of admission. During the three year study period, respiratory admissions at both hospitals accounted for 15 078 (47.3%) out of a total of 31 887 admissions. Acute respiratory infections accounted for 63.6% and asthma 37.4 % of these respiratory admissions. Two factors of interest were noted: (1) Considerably more males than females were admitted with both asthma and acute respiratory infections. (2) Asthma admissions to Red Cross Hospital among African children were proportionally much less than those of coloured children when compared to the proportions of admissions for acute respiratory infections. After removal of the seasonal effect, a multiple linear regression model was fitted to the data to determine the individual associations between admissions and ambient environmental variables. Significant associations were found between: (1) acute respiratory infections and oxides of nitrogen, soiling index, and temperature; (2) asthma and oxides of nitrogen (3) total admissions and soiling index, average temperature and minimum temperature (negative). The study concluded that despite generally low levels of air pollution in Cape Town, childhood respiratory admissions to Red Cross War Memorial Children's Hospital and Tygerberg Hospital were statistically significantly associated with some ambient air pollutants as well as temperature. However, given the nature of both the exposure and admissions databases, these results should be treated with caution. More representative site selections for air pollution monitors, as well as searching and controlling for possible confounding factors (i.e. indoor air pollution, parental smoking, overcrowding), would allow a better understanding of the current air pollution problem and the possible effects on the respiratory health of children in metropolitan Cape Town.
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Speir, Cameron Lindsey. "Two Cost Analyses in Resource Economics: The Public Service Costs of Alternative Land Settlement Patterns and Effluent Allowance Trading in Long Island Sound." Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/31154.
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This study offers two cost analyses to inform public policy decisions on the use of land and water resources. The first presents some public service costs associated with different spatial forms of land development. The second cost analysis presents costs associated with three different policy options for meeting water quality goals in Long Island Sound.
The objective the first analysis is to determine the cost to local governments of providing water distribution and wastewater collection services to alternative spatial forms of residential development. Components of spatial form are explicitly defined in terms of lot size, distance and tract dispersion. An engineering cost model is used to determine the water and sewer costs to three sets of hypothetical land settlement scenarios. Each set shows the effect of one component of spatial form on cost.
The results show that smaller lots, shorter distances between existing centers and less tract dispersion reduce public water and sewer costs. Lot size is found to have the most pronounced effect on water and sewer cost. Some policy options for reducing the public service costs associated with development are considered.
The objective of the second cost analysis is to analyze the cost implications of a nitrogen allowance trading system for wastewater treatment plants in Connecticut. Effluent allowance trading involves the transfer of pollution control responsibility between pollution sources. Effluent allowances are the right to discharge a given quantity of waste into the environment over a given time period. Allowance trading has been proposed as a way of reducing pollution control costs, encouraging innovative pollution prevention techniques and more quickly achieving water quality goals.
Long Island Sound, a major estuary in the northeastern United States, experiences chronically low dissolved oxygen levels. Excessive nitrogen loads from anthropogenic activities in the Sound watershed have been identified as the cause of the oxygen problem. The state of Connecticut is examining the possibility of introducing an effluent allowance trading system in order to reduce the cost of achieving required reductions in nitrogen discharge.
A linear programming model is used to predict trading outcomes and allowance prices. The total cost of achieving a nitrogen load cap is calculated under three administrative approaches. The first approach is a uniform reduction requirement where all plants are required to reduce discharge by the same proportion. The second approach is an administrative reallocation of waste load where a regulatory agency assigns control responsibility based on the agency's understanding of relative costs. The third approach is a flexible effluent allowance trading system. The results will show that a trading program offers cost savings over traditional regulatory approaches, demonstrate the potential for further cost savings from pollution prevention activities and estimate the cost savings that would result from including nonpoint sources in the overall nitrogen reduction strategy.
Master of Science
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Correa, Cano María Eugenia. "Macroecological patterns of plant species and anthropogenic activities." Thesis, University of Exeter, 2015. http://hdl.handle.net/10871/22975.
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The study of macroecology not only identifies patterns in the distribution and abundance of species at large spatial and temporal scales, it also gives insight into the processes underlying those patterns. The contribution of this work is not limited to helping develop the field of ecology per se, but also provides important insights into the understanding of large scale processes like climate change, the spread of introduced species, pest control and how increasing pressure from anthropogenic activities threatens biodiversity and ecosystem services. During the first decade following its formal inception, most of the progress in macroecology was made through studies of animal species, and research into plant species continues to lag far behind. This thesis contributes to the study of the macroecology of plant species by examining some selected macroecological patterns that have been studied only for animal species and by including an important issue that might have significant effects on diverse macroecological patterns, namely anthropogenic activities. The second and third chapters of the thesis address the generalised individuals-area relationship (GIAR) and the patch individuals-area relationship (PIAR), two macroecological relationships not previously explored for plant species. I show for the first time the existence of negative GIARs at the intraspecific and interspecific levels in plant species, similar to those documented for animal species. Unlike animal species, I did not find a broadly consistent intraspecific PIAR in plant species; more than half of the tested species showed negative PIARs. The resource concentration hypothesis may help explain those positive PIARs that were observed. The fourth chapter considers the effect of past human activities on current patterns of plant species richness at a landscape scale. Using a detailed database on the historical anthropogenic activities for Cornwall, U.K., I examine the relationship between species richness and the area covered by each historical land-use at two different spatial resolutions (10km x 10km and 2km x 2km). I find that at the 10km x10km scale human activities carried out since the 17th and 19th centuries explain an important proportion of the variation in current plant species richness. In contrast, a model at 2km x 2km scale with upland woods and the total land area of a grid cell explain only 5% of the variation. The fifth and sixth chapters focus on how artificial light at night (ALAN), which has increasingly come to attention as a significant anthropogenic pressure on species, is interacting with the distributions of plant species. In the fourth chapter, I consider the plant family Cactaceae to determine the proportion of the global distribution ranges of species that is being influenced by ALAN, and how this changes with the size of these distribution ranges and over a 21-year period (1992 to 2012). I found that >80% of cacti species are experiencing ALAN somewhere in their distribution range, and that there is a significant upward trend in ALAN in the ranges of the vast majority of species. For the sixth chapter, I consider similar issues for the threatened plant species of Britain, exploiting new remote sensing imagery of nighttime lighting at a very fine spatial resolution (c.340x340m2). Only 8% of Britain is free of artificial light at night and in consequence a high number of threatened plant species have a high proportion of their range under some influence of ALAN.
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Hayn, Michael, Steffen Beirle, Fred A. Hamprecht, Ulrich Platt, Björn H. Menze, and Thomas Wagner. "Analysing spatio-temporal patterns of the global NO2-distribution retrieved from GOME satellite observations using a generalized additive model." Universität Potsdam, 2009. http://opus.kobv.de/ubp/volltexte/2010/4499/.
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With the increasing availability of observational data from different sources at a global level, joint analysis of these data is becoming especially attractive. For such an analysis – oftentimes with little prior knowledge about local and global interactions between the different observational variables at hand – an exploratory, data-driven analysis of the data may be of particular relevance. In the present work we used generalized additive models (GAM) in an exemplary study of spatio-temporal patterns in the tropospheric NO2-distribution derived from GOME satellite observations (1996 to 2001) at global scale. We focused on identifying correlations between NO2 and local wind fields, a quantity which is of particular interest in the analysis of spatio-temporal interactions. Formulating general functional, parametric relationships between the observed NO2 distribution and local wind fields, however, is difficult – if not impossible. So, rather than following a modelbased analysis testing the data for predefined hypotheses (assuming, for example, sinusoidal seasonal trends), we used a GAM with non-parametric model terms to learn this functional relationship between NO2 and wind directly from the data. The NO2 observations showed to be affected by winddominated processes over large areas. We estimated the extent of areas affected by specific NO2 emission sources, and were able to highlight likely atmospheric transport “pathways”. General temporal trends which were also part of our model – weekly, seasonal and linear changes – showed to be in good agreement with previous studies and alternative ways of analysing the time series. Overall, using a non-parametric model provided favorable means for a rapid inspection of this large spatio-temporal NO2 data set, with less bias than parametric approaches, and allowing to visualize dynamical processes of the NO2 distribution at a global scale.
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Albalawi, Salem Mohammad S. "Daily air pollution levels and asthma : exploring the influence of time-activity patterns on personal exposure in Al Jubail industrial city, Saudi Arabia." Thesis, University of Newcastle upon Tyne, 2017. http://hdl.handle.net/10443/3566.
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Title: Daily air pollution levels and asthma; exploring the influence of time-activity patterns on personal exposure in Al Jubail industrial city, Saudi Arabia Introduction: Air pollution is a known risk factor for adverse cardio-respiratory health effects. In the last few years, epidemiological studies have provided evidence that exposure to air pollution can aggravate symptoms in asthmatic patients. Some epidemiological studies have used ambient air pollution levels based on fixed-site monitoring (FSM) data to evaluate the short-term effects of ambient air pollution levels on asthma-related emergency department visits (AEDv) using time-series analysis. In the recent past, technology has greatly improved, making it possible to carry out personal monitoring of indoor and outdoor microenvironments (ME). While the existing literature on time-activity patterns (TAP) and ME exposures for populations in the USA and Europe keeps on growing, little research on this topic has been carried out in the Middle East. This study was designed to (i) investigate the statistical association between exposure to air pollution and AEDv, and (ii) identify factors that influence personal exposure in different ME in Jubail Industrial City, Saudi Arabia. Methods: Daily number of AEDv, air pollution levels (particulate matter (PM2.5 and PM10), sulphur dioxide (SO2), carbon monoxide (CO) nitrogen oxides (NOx)) and weather variables (temperature and relative humidity) were obtained from the Royal Commission of Al Jubail Industrial City for the period between 2007 and 2011. Data were analysed using a time series approach, which involved application of a generalised linear model (GLM). Relative risks (RRs) were estimated using Poisson regression, while controlling weather variables, day of the week and holiday indicator for lag times of 0 - 7 days. RRs and 95% confidence intervals (CIs) in AEDv were calculated with each increment of inter-quartile range (IQR) change of each pollutant. Furthermore, to explore the influence of different ME on personal exposure levels, 27 students aged between 16-18 years were recruited and asked to record their detailed movements using a time-activity diary at 15-minute intervals over a period of 24 hours. The students were asked to carry a small backpack containing ii a personal air monitor to measure their personal exposure to PM2.5, and a GPS device to help identify ME including travelling, outdoors, at school and at home. Results: The association between AEDv and change in the quantity of SO2, NO2, PM2.5 and PM10 remained positive and statistically significantly after adjustment in the multi-pollutants model. The RR (in percent %) of AEDv increased by 5.4% (95% CI: 2.4, 8.5) at lag 2 for SO2 , 3.4% (95% CI: 0.8, 6.1) at lag 3 for NO2, 4.4% (95% CI: 2.4, 6.6) for PM2.5 and 2.2% (95% CI: 1.3, 3.2) for PM10 at lag 0 per IQR change in pollutants, 2.0ppb, 7.6ppb, 36μg/m3 and 140μg/m3 respectively. No significant associations between AEDv and CO were found. The time activity diary revealed that most of the students’ time was spent indoors (88.6%). The FSM median (IQR) PM2.5 level, 51.0μg/m3 (34.0-74.2), was significantly higher than personal median PM2.5 level, which was 30.0μg/m3 (20.9-42.4) (Wilcoxon p-value<0.001). Total personal outdoor median concentration of PM2.5, 44.4μg/m3 (31.1-59.5), was significantly higher than total personal indoor concentration, which was 28.3μg/m3 (19.2-40.2) (p-value<0.001). There was a significant but weak correlation between FSM and personal monitor PM2.5 levels when indoors (Spearman’s rank correlation=0.228, p-value < 0.001 n=544), but not at outdoors microenvironment. Conclusion: Current levels of ambient air pollution were associated with AEDv in Al Jubail. While there appear to be similarities between TAP in this small population sample from the Middle East and Europe/USA, the exposure levels in this industrial city appear to be very high, compared to the WHO air quality guidelines. The validity of FSM data as a proxy for personal exposure to PM needs to be characterised so that the exposure error associated with this proxy measure is better understood.
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Stendera, Sonja Johnson Richard K. "Spatiotemporal variability of chemistry and biota in boreal surface waters : a multiscale analysis of patterns and processes /." Uppsala : Swedish University of Agricultural Sciences, 2005. http://diss-epsilon.slu.se/archive/00000956/.
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Thesis (doctoral)--Swedish University of Agricultural Sciences, 2005.Thesis documentation sheet inserted. Appendix reproduces four papers and manuscripts co-authored with R.K. Johnson. Issued also electronically via World Wide Web in PDF format; online version lacks appendix.
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Assaghir, Zainab. "Analyse formelle de concepts et fusion d'informations : application à l'estimation et au contrôle d'incertitude des indicateurs agri-environnementaux." Phd thesis, Institut National Polytechnique de Lorraine - INPL, 2010. http://tel.archives-ouvertes.fr/tel-00587784.
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La fusion d'informations consiste à résumer plusieurs informations provenant des différentes sources en une information exploitable et utile pour l'utilisateur. Le problème de la fusion est délicat surtout quand les informations délivrées sont incohérentes et hétérogènes. Les résultats de la fusion ne sont pas souvent exploitable et utilisables pour prendre une décision, quand ils sont imprécis. C'est généralement due au fait que les informations sont incohérentes. Plusieurs méthodes de fusion sont proposées pour combiner les informations imparfaites et elles appliquent l'opérateur de fusion sur l'ensemble de toutes les sources et considèrent le résultat tel qu'il est. Dans ce travail, nous proposons une méthode de fusion fondée sur l'Analyse Formelle de Concepts, en particulier son extension pour les données numériques : les structures de patrons. Cette méthode permet d'associer chaque sous-ensemble de sources avec son résultat de fusion. Toutefois l'opérateur de fusion est choisi, alors un treillis de concept est construit. Ce treillis fournit une classification intéressante des sources et leurs résultats de fusion. De plus, le treillis garde l'origine de l'information. Quand le résultat global de la fusion est imprécis, la méthode permet à l'utilisateur d'identifier les sous-ensemble maximaux de sources qui supportent une bonne décision. La méthode fournit une vue structurée de la fusion globale appliquée à l'ensemble de toutes les sources et des résultats partiels de la fusion marqués d'un sous-ensemble de sources. Dans ce travail, nous avons considéré les informations numériques représentées dans le cadre de la théorie des possibilités et nous avons utilisé trois sortes d'opérateurs pour construire le treillis de concepts. Une application dans le monde agricole, où la question de l'expert est d'estimer des valeurs des caractéristiques de pesticide provenant de plusieurs sources, pour calculer des indices environnementaux est détaillée pour évaluer la méthode de fusion proposée.
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Carpenter, Evan S. "Identifying Cultural and Non-cultural Factors Affecting Litter Patterns in Hickory Creek, Texas." Thesis, University of North Texas, 2014. https://digital.library.unt.edu/ark:/67531/metadc699896/.
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Plastic deposition in hydrological systems is a pervasive problem at all geographic scales from loci of pollution to global ocean circulation. Much attention has been devoted to plastic deposition in marine contexts, but little is known about inputs of plastics into local hydrological systems, such as streams. Any attempt to prevent plastic litter must confront people’s behaviors, so archaeological concepts are used to distinguish between various cultural inputs (e.g., littering) and non-cultural forces (e.g., stream transport) that affect litter patterns on the landscape. Litter surveys along Hickory Creek in Denton, TX, are used to assess these factors.
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Mpherwane, Salome Kedibone. "An investigation into the allozyme genetic variation patterns among populations of freshwater fish from different river systems of Southern Africa." Thesis, University of Limpopo (Turfloop Campus), 2011. http://hdl.handle.net/10386/910.
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Saleh, Nadja, and Frida Jannebring. "Samband mellan medelhavskost, fisk- och skaldjursintag samt tjock- och ändtarmscancer : En litteraturstudie." Thesis, Uppsala universitet, Institutionen för folkhälso- och vårdvetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-439646.
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Background: Colon- and rectalcancer is the third most common cancer form worldwide. Previous research shows that unhealthy eating habits has a connection as a causal factor for cancer and that it's possible to prevent a third of all cancer cases with a changed diet. Medeiterranian diet consist of a high intake of seafood and is believed to be a healthpromoting diet. It is also a lower prevalence of cancer among the mediterranian coast. A WHO-report shows that about 1,5 - 2 % of all cancer cases have a connection to environmental pollution and nowadays most waters contains environmental pollution. Aim: The aim of this study was to update the state of knowledge between the mediteranian diet, it's frequency of seafood intake and colon- and rectal cancer in adults. Method: A literature review was used to answer the aim. The article search was made in PubMed where 12 articles were chosen and passed the quality review. Results: There was an ambiguously connection between mediterranean diet and the incidence of colon- and rectalcancer as research did not agree on whether there was a connection or not and the amount of studies used was limited. Some studies believe that there’s a significant connection while others believe that there isn’t any connection. The study partly confirms the connection between the intake of seafood and the prevalence of colon- and rectalcancer where they who ate according to the WHO-recommendations possibly had a smaller risk of developing colon- and rectalcancer compared to those who ate either more or less seafood than recommended. Conclusion: More research is needed in the field to ensure possible connection.Bakgrund: Tjock- och ändtarmscancer är den tredje vanligaste cancerformen världen över. Tidigare forskning visar att ohälsosamma matvanor har en koppling som orsak till cancer och att det genom att förbättra kostvanorna är det möjligt att förebygga en tredjedel av alla cancerfall. Medelhavskost med sitt höga intag av fisk- och skaldjur anses vara en hälsofrämjande kost och kring medelhavskusten är det en minskad förekomst av dödsfall orsakade av cancersjukdom. En rapport av WHO visar att ca 1,5–2 % av alla cancerfall har kopplingar till kemiska föroreningar och de flesta vatten innehåller numera kemiska föroreningar. Syfte: Syftet med studien var att uppdatera kunskapsläget för samband mellan medelhavskost, dess intag av fisk- och skaldjur och tjock-och ändtarmscancer hos vuxna över 18 år. Metod: En litteraturstudie användes för att besvara syftet. Artikelsökningen skedde i PubMed där 12 artiklar valdes ut och klarade kvalitetsgranskningen. Resultat: Ett tvetydigt samband fanns mellan medelhavskost och förekomsten av tjock- och ändtarmscancer då forskningen inte var överens om huruvida det finns ett samband eller inte samt att det var en begränsad andel studier. Vissa studier menar att det finns ett signifikant samband medan andra menar att det inte finns något samband. Studien stärker till viss del sambandet mellan fisk- och skaldjurintag och förekomst av tjock- och ändtarmscancer där de som åt fisk enligt WHO´s nuvarande rekommendationer möjligen hade en minskad risk för tjock- och ändtarmscancer jämfört med de som åt antingen mer eller mindre. Slutsats: Mer forskning behövs inom området för att säkerställa eventuella samband.
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Hall, Kimberlee K., Brian G. Evanshen, Kurt J. Maier, and Phillip R. Scheuerman. "Application of Multivariate Statistical Analyses to Microbial Water Quality Parameters in Four Geographically Similar Creeks in Northeast Tennessee to Identify Patterns Associating Land Use to Fecal Pollution Sources." Digital Commons @ East Tennessee State University, 2008. https://dc.etsu.edu/etsu-works/2947.
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Clyde, Gerard A. "Spatial and temporal patterns exhibited by select physicochemical and biological water quality parameters in Lake Texoma, Oklahoma and Texas." Thesis, University of North Texas, 2004. https://digital.library.unt.edu/ark:/67531/metadc4628/.
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From August 1996 through September 1997 eleven fixed stations were sampled monthly in January, March , April , July, August, September, and November and fortnightly in May and June for the purposes of establishing baseline conditions present in Lake Texoma as related to U.S. Army Corps of Engineers chloride control activities in the upper Wichita River, Texas. Five reservoir zones were identified a priori using historical chloride concentration data and include the Red River Zone (RRZ), Red River Transition Zone (RRTZ), Main Lake Body (MLB), Washita River Transition Zone (WRTZ), and Washita River Zone (WRZ) in order of decreasing chloride concentration. The existence of the WRTZ is not supported here, however the Big Mineral Arm in the RRTZ was observed to be highly independent of the mixing patterns observed in the RRTZ and was treated post priori separately from the RRTZ. Spatial and temporal comparisons between reservoir zones were performed on seventeen (17) physicochemical parameters from each of the eleven sampling stations and phytoplankton count data from one sampling station within each reservoir zone and physicochemical parameters were observed to exhibit a fixed spatial gradient. Strong density gradients throughout the reservoir were observed to occur in conjunction with vertical stratification of the water column. Stratification stability at individual stations was attributable to both thermal and salinity density gradients throughout the period of stratification with the degree to which stratification is thermally or chemically induced influenced by inter-annual variability in hydraulic residence time. Hypolimnetic oxygen depletion rates were also observed to be affected by changes in hydraulic residence time with a long-term trend of decreasing relative areal hypolimnetic oxygen rates detected between the 1970s and 1990s. The algal assemblage present in Lake Texoma is dominated by the Cyanophyta, which comprises 82.1 % of the assemblage total standing crop with one species, Microcystis incerta, comprising 57.0 % of the assemblage total standing crop and is typical of a temperate eutrophic lake. The algal assemblage was affected more by temporal dynamics rather than spatial dynamics with variance observed in the algal assemblage attributable to physicochemical factors which vary through time.
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Guerrero, Viviana Vanesa Urbina. "Condições atmosféricas associadas à dispersão de poluentes nas cidades de São Paulo e Santiago." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/14/14133/tde-20042016-161502/.
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Este trabalho teve como objetivo analisar as condições meteorológicas favoráveis e desfavoráveis à dispersão de poluentes, com ênfase no ozônio, nas áreas urbanas associadas à Região Metropolitana de São Paulo (RMSP) e a Grande Santiago (GS). Medidas de concentração de estações localizadas em ambas as áreas de estudo foram utilizadas para determinar o comportamento médio, o número de ocorrências de ultrapassagens de padrão de qualidade do ar e o aumento noturno das concentrações de ozônio num período de dez anos. Foi encontrado que o máximo horário acontece próximo das 14 horas (horário local) nas duas regiões, e que existe uma tendência à diminuição no número de ultrapassagens do padrão de qualidade do ar associado a este poluente. Na RMSP é possível observar um máximo secundário durante a madrugada, enquanto que este fenômeno não é claramente observado nos valores médios de concentração na GS. Com dados da Reanálise do NCEP/NCAR foi visto que a ocorrência deste fenômeno está associada a configurações sinóticas específicas na GS, enquanto que na RMSP não existe padrão sinótico específico que diferencie casos com e sem aumento de ozônio noturno. Um novo módulo fotoquímico (NPM), contendo 95 reações foi inserido no modelo BRAMS na tentativa de melhorar o prognóstico das concentrações de poluentes, principalmente em relação ao ozônio. O NPM mostrou melhor desempenho que o módulo fotoquímico original do modelo (SPM; Simple Photochemical Module) para todos os poluentes considerados, salvo o ozônio, para o qual o SPM apresentou melhores índices estatísticos em 5 das 7 estações avaliadas. As características locais associadas à ocorrência simultânea ou não de aumento na concentração de ozônio foram estudadas utilizando o modelo BRAMS com o módulo SPM ativado, sendo verificado que o aumento de ozônio na RMSP está associado, principalmente, ao transporte vertical deste poluente a partir de níveis mais elevados da atmosfera, enquanto que o transporte horizontal é a maior contribuição para o aumento das concentrações de ozônio durante o período noturno na GS.This work aimed to analyze the favorable and unfavorable meteorological conditions for pollutant dispersion, especially ozone, at the Metropolitan Area of São Paulo (MASP) and the Greater Santiago (GS). Ozone concentration measurements from stations located in both urban areas were used to determinate the mean behavior, the number of standard air quality exceedances and the increase on nocturnal ozone concentration over a 10 years period. It was found that the diurnal maximum occurs around 14 local time in both urban areas, and that there is a diminishment tendency of the total cases of standard air quality exceedances during all period. A secondary maximum of ozone concentration was observed in MASP at night, which was not clearly seen on mean values over GS. By using the NCEP/NCAR Reanalysis data it was seen that the occurrence of this phenomenon is associated to specific synoptic patterns for GS, while there is no specific synoptic pattern for the MASP cases, with or without nocturnal increase in ozone concentrations. A New Photochemical Module (NPM), containing 95 reactions was coupled to BRAMS model in an attempt to improve the prediction of air pollutants, especially ozone. The NPM showed a better performance than the original module, the SPM (Simple Photochemical Module), for all considered pollutants but ozone. For this pollutant, the SPM presents better statistical indexes for 5 of the 7 stations analyzed. The local characteristics related to simultaneous occurrence of nocturnal ozone increase was studied using the SPM-BRAMS model, which showed that the secondary nocturnal maximum of ozone concentrations in MASP are related to vertical transport of this pollutant from higher levels of the atmosphere to the surface, while the horizontal transport is a major contributor to the increase of ozone concentrations in the GS during the night.
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Fox, John Tyler. "Spatiotemporal Patterns and Drivers of Surface Water Quality and Landscape Change in a Semi-Arid, Southern African Savanna." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/81462.
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The savannas of southern Africa are a highly variable and globally-important biome supporting rapidly-expanding human populations, along with one of the greatest concentrations of wildlife on the continent. Savannas occupy a fifth of the earth's land surface, yet despite their ecological and economic significance, understanding of the complex couplings and feedbacks that drive spatiotemporal patterns of change are lacking. In Chapter 1 of my dissertation, I discuss some of the different theoretical frameworks used to understand complex and dynamic changes in savanna structure and composition. In Chapter 2, I evaluate spatial drivers of water quality declines in the Chobe River using spatiotemporal and geostatistical modeling of time series data collected along a transect spanning a mosaic of protected, urban, and developing urban land use. Chapter 3 explores the complex couplings and feedbacks that drive spatiotemporal patterns of land cover (LC) change across the Chobe District, with a particular focus on climate, fire, herbivory, and anthropogenic disturbance. In Chapter 4, I evaluated the utility of Distance sampling methods to: 1) derive seasonal fecal loading estimates in national park and unprotected land; 2) provide a simple, standardized method to estimate riparian fecal loading for use in distributed hydrological water quality models; 3) answer questions about complex drivers and patterns of water quality variability in a semi-arid southern African river system. Together, these findings have important implications to land use planning and water conservation in southern Africa's dryland savanna ecosystems.Ph. D.
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Mansui, Jérémy. "Observation et modélisation des macro-déchets en mer Méditerranée, de la large échelle aux échelles côtière et littorale." Thesis, Toulon, 2015. http://www.theses.fr/2015TOUL0015/document.
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L'objectif général de cette thèse est d'étudier les mécanismes de transport des déchets marins flottants ainsi queleur accumulation potentielle en Méditerranée, en s'appuyant sur la modélisation numérique de leur dérive ainsique sur des observations in-situ de leur distribution. La dynamique du transport des déchets marins y estnotamment analysée en terme d'échelles caractéristiques du bassin, en partant de la grande échelle jusqu'auxéchelles côtière et littorale.Dans un premier temps, l'examen d'un ensemble d'expériences Lagrangiennes numériques a permis d'identifierdans le bassin des zones probables d'accumulation non permanentes à grande échelle (Mansui et al., 2015a).L'impact à l'échelle côtière d'un courant de bord (Courant Nord) et des forçages atmosphériques sur ladistribution locale et l'échouage des déchets marins flottants a ensuite pu être estimé en utilisant notammentdes données originales recueillies en mer et à terre (Mansui et al., 2015b, en révision)The main objective of this work is to study the floating marine debris transport mechanisms and their potentialaccumulation in the Mediterranean Sea, using numerical modelling and in-situ observations of debris. Thetransport dynamics is analysed in terms of typical scales in the basin, from the large scale to the coastal andlocal scales.First, the analysis of a Lagrangian experience data set show the potential existence of non-permanent and largeretention areas (Mansui et al., 2015a). In a second stage, the coastal impact of a boundary current (the NorthernCurrent) and atmospheric forcings on the local distribution and stranding of floating marine litter has beenestimated (Mansui et al., 2015b, under revision), using an original set of data combining offshore sightings andbeaching surveys
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Minot, Marceau. "Traits biologiques et facteurs environnementaux structurant les mouvements locaux et la dispersion des libellules( Insecta, Odonata) dans les réseaux de mares. Pond creation and restoration:: patterns of odonate colonisation and community dynamics Biometry of the large dragonfly Anax imperator (Odonata, Aeshnidae):: A study of traits from larval development to adults Effects of water pollution on the larval development and condition of the adults at emergence in Aeshna cyanea (Odonata: Aeshnidae) Habitat use and movements of a large dragonfly (Odonata: Anax imperator) in a pond network. Diversity and genetic structure of Anax imperator populations at the European scale." Thesis, Normandie, 2020. http://www.theses.fr/2020NORMR031.
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Au cours des dernières décennies, le nombre de mares a connu un déclin de plus de 50 % dans les pays européens, atteignant parfois jusqu'à 90 % dans certaines régions. Cette diminution a entraîné une forte perte de connectivité entre les mares. Pourtant, ces écosystèmes petits et dispersés sont essentiels au cycle de vie d'une grande diversité d'espèces d'eau douce. Les politiques d'aménagement du territoire, comme la création des Trames Vertes et Bleues en France, visent à améliorer les continuités écologiques pour permettre le maintien des populations existantes et les échanges entre elles. Cependant, les études de connectivité entre les mares doivent prendre en compte les capacités de dispersion des espèces et cette information fait souvent défaut pour orienter les mesures de restauration. Dans le présent travail, nous avons étudié les capacités de dispersion des libellules à plusieurs échelles spatiales ainsi que les caractéristiques biologiques et les facteurs environnementaux qui façonnent leurs mouvements. Dans la première partie, nous avons évalué la colonisation par les libellules de 20 mares normandes pendant les trois années suivant leur création ou leur restauration. Les résultats mettent en évidence des taux de colonisation élevés pendant la première année et aucune différence de richesse spécifique n'a été constatée entre les mares nouvellement créées ou restaurées. Cela suggère que la restauration des mares après un assèchement total ne devrait pas toujours être prioritaire par rapport à la création de nouvelles mares dans les stratégies de gestion. Nous avons constaté que les espèces généralistes étaient davantage présentes la première année après la création ou la restauration des mares, alors que la présence d’espèces spécialistes des forêts augmentait avec l'âge du plan d’eau. Les résultats ont également mis en évidence que le contexte paysager autour des mares (i.e. milieu forestier ou ouvert) avait un effet sur la composition des communautés de libellules. Enfin, l'abondance totale des espèces d'odonates était liée à la densité des plans d’eau alentours. Ce résultat souligne que les mares très connectées peuvent abriter des populations plus importantes que les mares isolées et donc être plus résistantes aux perturbations. La deuxième partie fournit des éléments sur le développement larvaire d'Anax imperator et la relation entre les caractéristiques morphologiques des larves et des adultes. Les résultats suggèrent que la survie de cette espèce pendant la période de maturation pourrait dépendre de la longueur des individus. Nous avons également essayé d'étudier la dispersion natale en marquant 87 individus à l'émergence, mais seuls deux mâles ont été retrouvés après la période de maturation. Enfin, l'effet de deux polluants de l'eau (Round-up et DEET) sur le développement larvaire et les adultes d'Aeshna cyanea a également été étudié à différentes concentrations. Les larves ont été élevées dans des conditions de laboratoire et exposées à des concentrations allant jusqu'à 30 mg.L-1 des deux polluants. Aucun effet des polluants sur les conditions morphologiques des larves ou des ténéraux n'a été détecté, ce qui suggère que A. cyanea est une espèce tolérante aux potentielles pollutions de l'eau dans les mares. Le niveau de la protéine de stress HSP70 était également similaire selon les différents traitements, mais les adultes ténéraux présentaient des niveaux de stress plus élevés que les larves, ce qui suggère que l'émergence a provoqué un stress élevé chez les individusDuring the last decades, the number of ponds decreased by more than 50 % in European countries, occasionally reaching up to 90 % in some regions. Their decline in number has led to a strong loss of connectivity between waterbodies. Yet, these small and scattered ecosystems are essential for the life cycle of a high diversity of freshwater species. Land use policies like the creation of Greenways and Blueways in France aim to improve ecological continuities to allow maintenance of existent biological populations and exchanges between them. However, the connectivity between ponds must be considered according to the dispersal abilities of freshwater species and this information often lacks to guide restoration measures. In the present work, we studied the dispersal abilities of dragonflies on several spatial scales and investigated the biological traits and environmental factors that shaped their movements. In the first part, we evaluated the colonization of 20 ponds in Normandy by dragonflies during three years after pond restoration or pond creation. The results highlight high colonization rates during the first year and no difference in species richness was found between newly created or restored ponds. This suggests that restoration of ponds after complete drought should not always be prioritized over pond creation in management strategies. We found that generalist species were more present in the first year after pond creation or restoration, whereas the occurrence of forest specialists increased with the age of the pond. The results also highlighted that the landscape context around ponds (i.e. forest vs. open lands) had an effect on the composition of dragonfly communities. Finally, the total abundance of odonate species was related to the density of other ponds in the surroundings. This result emphasizes that highly connected ponds can support larger populations than isolated ones and thus, be more resilient to perturbations. The second part provides insights into the larval development of Anax imperator and the relationship between morphological traits of larvae and adults. The results suggest that the survival of this species might depend on its body length during the maturation period. We also tried to study the natal dispersal by marking 87 individuals at emergence, but only two males were resighted after the maturation period. Finally, the effect of two water pollutants (i.e. Round-up and DEET) at different concentrations was also investigated on the larval development and adults of Aeshna cyanea. Larvae were reared under laboratory conditions and exposed to concentrations up to 30 mg.L-1 of the two pollutants. No effect of the pollutants was detected on the morphological conditions of larvae or tenerals, suggesting that A. cyanea is tolerant to potential water pollution of ponds. The level of HSP70 stress protein was also similar according to the different treatments, but teneral adults presented higher levels of stress than larvae, suggesting that emergence induced a high stress in the individuals. The third part focuses on the dispersal of A. imperator. We first assessed the local movements within a pond network in the Normandy region
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Gineste, Benoit. "Étude de la biologie et de la vulnérabilité au développement anthropique des oiseaux marins nocturnes à La Réunion." Thesis, La Réunion, 2016. http://www.theses.fr/2016LARE0015/document.
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La biodiversité est actuellement fortement menacée par les activités humaines. Dépendant des milieux marins et terrestres, les oiseaux marins sont particulièrement exposés aux pressions anthropiques. À La Réunion, les conséquences des impacts des aménagements sur les populations restent méconnues. Dans une optique de conservation et de réalisation d'études environnementales pertinentes, des informations fiables sur la répartition des espèces, sur leur comportement de vol et une évaluation de leur vulnérabilité vis-à-vis des aménagements sont nécessaires. Les objectifs de cette thèse sont de préciser des données biologiques et d'évaluer la vulnérabilité des oiseaux marins nocturnes de La Réunion face aux aménagements. Nous avons étudié l'évolution de la taille et de la répartition des colonies de puffin tropical Puffinus bailloni à l'échelle de l'île sur une période de 19 ans. Les patterns de vol du puffin tropical et du pétrel de Barau Pterodroma baraui ont été caractérisés par imagerie radar à différentes échelles temporelles et spatiales. Nos résultats montrent une stabilité apparente de la population de puffin tropical malgré la forte pollution lumineuse. Le puffin tropical et le pétrel de Barau présentent des patterns de vol spécifiques. Les effectifs estimés de pétrel de Barau suggèrent une population plus importante que celle connue actuellement. Les effectifs estimés de puffin tropical sont cohérents avec les estimations actuelles. Les jeunes pétrels de Barau s'envolent principalement durant les premières heures de la nuit. Des outils d'aide à la décision ont été produits. Nos travaux soulèvent la nécessité de poursuivre des recherches fondamentales et appliquéesThe biodiversity is currently threatened by human activities. As they depend both of marine and terrestrial habitats, seabirds are particularly exposed to human pressures. In Reunion Island, the consequences of the urbanization on populations are unknown. For conservation and environmental assessment purposes, accurate information on the species repartition, flight patterns and vulnerability to infrastructure is required. The goals of this thesis are to update biological information on species and to assess the vulnerability of nocturnal seabirds of Reunion Island exposed to infrastructure. We studied the evolution of the size and the repartition of the colonies of tropical shearwater Puffinus bailloni at the scale of the entire island over a 19-years period. The flight patterns of tropical shearwater and Barau's petrel Pterodroma baraui were described with radar technology at different spatial and temporal scales. Our results show an apparent stability of the tropical shearwater population despite an important light pollution. Tropical shearwater and Barau’s petrel present specific flight patterns. The estimated census of Barau's petrel suggests a population size higher than current estimation whereas the estimated census of tropical shearwater is reliable to current estimations. Barau's petrels' juveniles mostly take off during the first hours of the night. Decision making tools have been produced. Our study also highlights the need to conduct further fundamental and applied researches
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Wu, Yu-ping, and 伍玉平. "The Analysis of Air Flow Pattern For Pollution Control." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/53561244085727739161.
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碩士國立中山大學
機械與機電工程學系研究所
90
In recent years, the demand for higher cleanliness and air quality control of the indoor environment is increasing especially during the manufacturing process. Although different design standards and codes were adapted worldwide, the air flow pattern analysis still dominates the design process. The parameters affecting the design process were cross-examined, including the air change rate, clean room sizes and layout, air supply and exhaust ports layout, unbalanced supply and exhaust air volume (QR=1.2QS), until system optimization is achieved. Furthermore, FFU system with 0.46m/s air speed was identified to be appropriate for injection module designs. In order not to increase manufacturing cost, the FFU can be design with three-fiered speed control to provide energy efficiency with space flexibility. However, in low-speed operation, the slightly positive pressure cannot be maintained properly and should be avoided to operate in unconditioned rooms.
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Ho, Sheng-Wei, and 何勝惟. "Multivariate Analysis of Soil Heavy Metal Pollution and Land Use Pattern in Taiwan." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/40938447747739756301.
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碩士國立臺灣大學
生物環境系統工程學系暨研究所
90
Factor analysis and landscape indices were used to find out the relationship between the land use and soil heavy metal pollution in Tao-Yuan, Hsin-Chu, Chang-Hua, and Kao-hsiung. The study revealed that soil heavy metal and landscape patterns could be grouped into the factor model that account for all of the variation. A landscape pattern is a mixture of natural and human-managed patches that vary in size, shape, and arrangement, and result from complex interactions of physical, biological, and social forces. The following landscape indices for each sampling site were used to characterize landscape patterns and land use including; Shannon Weaver Diversity Index (SDI), Area-Weight Mean Shape Index (AWMPFD), density of irrigation ditches (DL), the ratio of urban planning area (RAup), Nearest Neighbour Index (R) and number of plants. Semiconductor Manufacturing and Printed Circuit Board are the most important industries in Tao-Yuan and Hsin-Chu areas, wastewaters discharge are the major reason for soil pollution. Fragmentation caused by urbanization and industrialization in Chang-Hua is the main reason of soil pollution in this region.
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Hong, Jia-Hong, and 洪嘉宏. "Analysis of Air Flow Pattern and Pollution Control in the Mini-Environment of Injection Molding Clean Room." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/28855246120235118012.
Full textAbstract:
碩士國立中山大學
機械與機電工程學系研究所
91
High technology industries have stringent on clean room environment. Traditional ballroom type clean room can’t meet the requirement in many cases. The uni-directional laminar ballroom type cleanroom is can’t fulfill such requirement. The adoption of Mini-Environment technology is becoming the mainstream of the environment control technology for high technology industries process. It is the goal of this project to simulate and design the air flow pattern, in using the current injection machine as a model, to achieve the cleanliness of class 1,000 – 10,000. There are four major steps in achieving this goal, Namely: 1、The dynamic 3D CFD simulation of the flow pattern of the clean bench. 2、The evaluation of the pollution source and its impact on the overall cleanliness 3、The basic design of the class 1,000 cleanroom for this machine 4、The modification necessary to achieve this goal through design iterations. The results of this research are useful in the understanding of the flow characteristics in a mini-environment. The buffer zone of laminar flow was found to be effective to avoid cross contamination with the outside environment during door opening. The height of the processing opening of the mini-environment is found to be an important factor on the flow turbulent intensity and particle concentration. Concentration due to an operator can also be reduced by this buffer zone. The numerical techniques developed can also be used as numerical models in future studied.
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DI, CHIO ROBERTO. "Theoretical and Practical Aspetcts of the Catalytic Pattern of Nanostructured MnCeOx Systems for Environmental Applications." Doctoral thesis, 2018. http://hdl.handle.net/11570/3131264.
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The technological development of human beings over the last few centuries has led them to produce great quantities of atmospheric pollutants. Nowadays, large areas of the globe find themselves facing pollution phenomena that undermine people's health, causing serious damage to the respiratory system, as well as to the ecosystems. Catalytic oxidation technologies proved to be successful in preventing or mitigating harmful gaseous emissions, but their large-scale exploitation is bound to the development of efficient and economical catalytic systems. Transition Metal Oxide catalysts, and in particular those based on Mn, have demonstrated excellent oxidative capacities in various applications such as the mineralization of toxic organic compounds from wastewater (CWAO), the oxidative detoxification of gas exhausts, the selective NOx reduction (SCR), the synthesis of bio-fuels and fine chemicals, showing performance comparable or even superior to the traditional noble metal systems. Among these, the catalytic oxidation of carbon monoxide has a great value both from a scientific and technological point of view: in fact, it is considered a model reaction, which can provide basic information on the reactivity of heterogeneous catalysts but at the same time, many are the possible fields of application, ranging from the purification of industrial streams (e.g., PROX) to the development of ambient temperature operating systems for indoor or mobile applications (e.g., gas masks, gas sensors).
In this context, the work of this thesis is aimed at analyzing the practical and theoretical aspects of the oxidation of carbon monoxide on MnCeOx catalysts. To achieve this goal, a series of samples with different Ce content was synthesized by the redox precipitation method and tested by means of Temperature Programmed Catalytic Reaction (TPCR) in the CO oxidation reaction. From a systematic comparison of the bulk (e.g., XRD, Raman, BET) and superficial (XPS) characterization data, with the results of catalytic activity, it was possible to identify the Mn(IV) sites as main responsible for the marked oxidation activity of the MnCeOx systems. Subsequently, the empiric reaction kinetics and mechanistic issues of the CO oxidation reaction were assessed on a model MnCeOx (i.e., M5C1) catalyst. The numerous mechanistic evidences collected, led us to the formulation of a Langmuir-Hinshelwood reaction mechanism and the relative kinetic equation. The last goal of this work was to obtain a reaction model able to predict the reactivity pattern of the studied catalyst in a wide range of experimental conditions in terms of temperatures (293-533K), reagents pressure (p0CO-p0O2, 0.00625-0.025 atm) and CO/O2 ratio (λ0, 0.25-4.0).
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Magerman, Ruben Clive. "Effects of an argumentation-based instruction on grade 10 learnersâ understanding of the causes of pollution at a river site." Thesis, 2011. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_3465_1319195566.
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This study was based on the Science and Indigenous Knowledge Systems Project (SIKSP) at the School of Science and Mathematics Education, University of the Western Cape. The project seeks to enhance educatorsâ understanding of and ability to implement a Science-IKS curriculum (Ogunniyi, 2007) through using the theoretical framework of argumentation (Toulmin Argument Pattern) to the extent that learners would value the significance of both worldviews. This study sought to find the effects of an Argumentation-Based Instruction on grade 10 learnersâ understanding of the causes of pollution at a river site. Since the integration of Science and IKS are envisaged by Curriculum 2005 (C2005), two theoretical argumentation constructs have been used namely, Toulminâs (1958) Argumentation Pattern (TAP) and Ogunniyiâs (1995) Contiguity Argumentation Theory (CAT).
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Mohamed, Mostafa H. A., and R. S. Sharma. "Patterns and mechanisms of light non-aqueous phase liquid in unsaturated sand." 2003. http://hdl.handle.net/10454/2676.
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NoThe paper presents patterns and mechanisms of light non-aqueous phase liquid (LNAPL) migration in an unsaturated/saturated sand, based on a detailed experimental investigation using a fully instrumented two-dimensional model with dimensions of 120 x 120 x 10 cm. Suction head and degree of saturation were monitored simultaneously using tensiometers and time domain reflectometry (TDR) transducers respectively. LNAPL spills into the unsaturated zone were simulated to investigate the influence of new variables of practical importance, including the spill area, volume of spill and fluctuations of groundwater table, on the patterns of LNAPL migration. The patterns are explained in terms of the relationship between matric suction and degree of saturation. Fluctuations of water level are found to have a major influence on the distribution of LNAPLs in the unsaturated/saturated sand for large volumes of LNAPL spill. Measurements of degree of saturation of water at different levels are used to explain the LNAPL migration. It was found that water suction head was not affected by migrating LNAPL if the degree of saturation of water was above the residual saturation. Results of LNAPL suction head were found to be consistent with the migration patterns. Additionally, the average suction head difference between different levels indicated accurately the direction of LNAPL migration, which was in good agreement with the patterns observed using electronic imaging.
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Gilbreath, Yvonne Janiece. "Shifting pollution patterns in the production of refined oil products and industrial chemicals under NAFTA." 2002. http://wwwlib.umi.com/cr/utexas/fullcit?p3099450.
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Gaumnitz, Lisa Lynn. "Science frames and informational patterns a content analysis of newspaper coverage of an air pollution reduction program /." 1993. http://catalog.hathitrust.org/api/volumes/oclc/33099241.html.
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Thesis (M.S.)--University of Wisconsin--Madison, 1995.Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 61-64).
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Fowles, AE. "Assessing anthropogenic impacts on reef communities: patterns, indicators and processes." Thesis, 2017. https://eprints.utas.edu.au/23842/1/Fowles_whole_thesis.pdf.
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Estuaries have been favoured for human settlement, and since then have slowly deteriorated as a consequence of multiple and interacting anthropogenic impacts in their unique sheltered environments. The capacity to predict which urban impacts are most severely affecting benthic communities is essential for estuarine biological conservation. Understanding urban effects and key biological responses may help to determine where impacts take place, if effects are reversible, and how pollution affects flow through the estuarine ecosystem. In this thesis, I apply observational surveys and experimental manipulation to examine patterns in sessile communities in the marine component of estuaries, and to link changes in the ecosystem to pollution sources.
In one of the first studies to consider large scale patterns of rocky reef communities across multiple estuaries, I investigated the influences of environmental and anthropogenic factors in influencing the composition, cover and dominance of macro-algae and sessile invertebrates. Reef Life Survey underwater transect protocols were conducted in three large urban estuaries. I utilised information from photo-quadrats to disentangle natural and human impact variables and describe an environmental baseline for current sessile community patterns within these ecosystems. Statistical model selection was conservative, with environmental variables entered into the models first, and then human effects accounted for. I then tested for significant patterns for functional groups. Heavy metals and proximity to ports appeared to be the major anthropogenic drivers of patterns of temperate reef sessile biota, with functional group response consistent and generalizable for two of the three estuaries. Comparison between the three capital city estuaries highlighted a clear effect of intense urbanisation and the complex nature of historical and contemporary pollution effects on biota.
To further disentangle the effects of different pollution types on sessile reef assemblages, I conducted a manipulative experiment in one of the most heavily polluted estuaries worldwide (Derwent Estuary, Hobart). I translocated healthy sessile communities grown on concrete pavers to locations adjacent to marinas, sewerage outfalls, fish farm cages, and stormwater discharges, each with associated controls. Reef communities subjected to chronic levels of pollution in the most heavily urbanised area differed from those outside this area, with perennial Laminariales largely replaced by stress-tolerant species. Pollution types differed in their effects on transplanted communities, with marinas showing greatest negative impact, with significant losses in canopy and foliose macroalgae. Communities near fish farms, marinas and storm water drains were characterised by abundant filamentous algae.
A concurrent experiment using bare pavers assessed the effects of the four different pollution sources on recruitment of native and non-indigenous algae and sessile invertebrates on rocky reefs in the degraded Derwent estuary over a one year period. Non-indigenous and cryptogenic species showed significantly higher cover on experimental pavers near marinas and sewerage drains compared with associated control sites. The cover of opportunistic species was significantly higher near fish farms and sewerage outfalls, and the cover of some native species was amplified at sewerage outlets relative to the control sites. Colonisation of less desirable algal communities seems to be accelerated by some urban impacts. Results suggest that careful consideration of urban drainage is required to reduce introductions of invasive algal species. Redirection of outlets offshore into better flushed areas and relocation of dense fish farm leases away from partially enclosed areas may help reduce some of the negative changes to sessile communities.
Impacts of urban pollution on benthic assemblages can be direct or indirect, through ecological interactions. I analysed invertebrate macro and mesograzer abundances from pavers used for the reef transplantation experiment to explore the potential mediation of pollution impacts through effects of pollution on mobile fauna. Log response ratios and structural equation modelling indicated that observed responses of algal groups and grazers were directly affected by pollution, rather than through trophic pathways involving interactions between these groups.
Overall, this study provides important information to improve management in estuarine systems with macroalgal-dominated reefs. Urbanisation has clearly led to large-scale decline in abundance of ‘healthy’ sessile benthic species, with persisting species presumably living near their tolerance limits. Current pollution loads need to be minimised if we are to
maintain and restore the unique and undervalued reef communities in the increasingly urbanised environment of estuaries.
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"Spatiotemporal Patterns, Monitoring Network Design, and Environmental Justice of Air Pollution in the Phoenix Metropolitan Region: A Landscape Approach." Doctoral diss., 2014. http://hdl.handle.net/2286/R.I.25096.
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abstract: Air pollution is a serious problem in most urban areas around the world, which has a number of negative ecological and human health impacts. As a result, it's vitally important to detect and characterize air pollutants to protect the health of the urban environment and our citizens. An important early step in this process is ensuring that the air pollution monitoring network is properly designed to capture the patterns of pollution and that all social demographics in the urban population are represented. An important aspect in characterizing air pollution patterns is scale in space and time which, along with pattern and process relationships, is a key subject in the field of landscape ecology. Thus, using multiple landscape ecological methods, this dissertation research begins by characterizing and quantifying the multi-scalar patterns of ozone (O3) and particulate matter (PM10) in the Phoenix, Arizona, metropolitan region. Results showed that pollution patterns are scale-dependent, O3 is a regionally-scaled pollutant at longer temporal scales, and PM10 is a locally-scaled pollutant with patterns sensitive to season. Next, this dissertation examines the monitoring network within Maricopa County. Using a novel multiscale indicator-based approach, the adequacy of the network was quantified by integrating inputs from various academic and government stakeholders. Furthermore, deficiencies were spatially defined and recommendations were made on how to strengthen the design of the network. A sustainability ranking system also provided new insight into the strengths and weaknesses of the network. Lastly, the study addresses the question of whether distinct social groups were experiencing inequitable exposure to pollutants - a key issue of distributive environmental injustice. A novel interdisciplinary method using multi-scalar ambient pollution data and hierarchical multiple regression models revealed environmental inequities between air pollutants and race, ethnicity, age, and socioeconomic classes. The results indicate that changing the scale of the analysis can change the equitable relationship between pollution and demographics. The scientific findings of the scale-dependent relationships among air pollution patterns, network design, and population demographics, brought to light through this study, can help policymakers make informed decisions for protecting the human health and the urban environment in the Phoenix metropolitan region and beyond.Dissertation/Thesis
Ph.D. Biology 2014
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Roffe, Sarah Jane. "An investigation into the spatio-temporal patterns of modelling SO2, NOx and surface O3 across the Highveld priority area, South Africa." Thesis, 2017. http://hdl.handle.net/10539/23542.
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A thesis submitted to the Faculty of Science, University of the Witwatersrand, in fulfillment of the requirements for the degree of Master of Science. Johannesburg, 2017.The Highveld is identified as an air pollution ‘hotspot’ area where pollutant concentrations are elevated due to the high density of industrial and non-industrial air pollution sources. To enhance air quality across the Highveld, it was declared a priority area to manage and monitor pollutants to reduce their negative impact on the environment and society. Hence, the aim of this study was to investigate ambient air pollution across the Highveld Priority Area (HPA), using ground-level SO2, NOx and surface O3 concentrations, meteorological parameters and Moderate resolution imaging spectroradiometer (MODIS) atmosphere products, for January to December 2011, to develop new modelling techniques to aid in the management of air pollution. Results show the annual mean trace gas concentrations of SO2, NOx and surface O3 were 12.14, 14.75 and 28.77 ppb, respectively. SO2 and NOx concentrations were highest during winter at an average of 17.56 and 20.96 ppb, where surface O3 concentrations were highest during spring at an average of 32.82 ppb. Diurnal patterns of SO2 and surface O3 were similar, where a midday peak occurred. NOx concentrations instead showed peaks during traffic hours. Ambient air temperature, solar radiation, relative humidity, wind speed and rainfall levels peaked during summer. Atmospheric pressure was relatively stable throughout the year. Winds typically ranged from N to E up to April and from S to NW from May. Very little variation in SO2 and NOx concentrations was explainable by meteorology, 4 to 29 % and 5 to 23 %, while the influence of meteorology on surface O3 concentrations was more significant, 23 to 53 %. Spatial multiple regression statistical models using a cross validation approach for model validation were made over a number of temporal scales. The model fitting and validation processes indicated that the models were not a good fit as only up to 69, 74 and 58 % of SO2, NOx and surface O3 concentrations with high root means square error (RMSE) values of up to 22.10, 15.56 and 18.59 ppb, respectively, could be explained by the models. This process revealed the potential to model pollutants across the HPA, and as a pilot study future work can be based on this study. It is clear that spatial modelling for pollution estimation and management is necessary as seen by the frequent exceedances of the national and international ambient air quality standards.
XL2017
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Brauer, Michael, Jochen Brumm, and Stefanie Ebelt. "Evaluation of ambient air pollution in the Lower Mainland of British Columbia: Public health impacts, spatial variability, and temporal patterns." 2000. http://hdl.handle.net/2429/875.
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John, Juanette. "Lead exposure of children attending pre-school facilities in certain geographical areas of Pretoria, in relation to their activity patterns : a cross-sectional study." Diss., 2003. http://hdl.handle.net/2263/28025.
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"Determining the influences of land use patterns on the diatom, macroinvertebrate and riparian vegetation integrity of the Lower Harts/Vaal River systems." Thesis, 2010. http://hdl.handle.net/10210/3268.
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M.Sc.Water resources in South Africa are scarce and need to be protected and managed in a sustainable way for future generations. Food supply is a great priority worldwide and the pressure to produce enough food has resulted in the expansion of irrigation and the steadily increasing use of fertilizers and pesticides to achieve higher yields. Rivers are impacted by agriculture through increased suspended sediment loads (which affects primary production, habitat reduction and introduction of absorbed pollutants), elevated nutrient inputs (which may increase the abundances of algae and aquatic plants), salinization and pesticide runoff (which eliminates species intolerant to these conditions and therefore impacts on the normal production of the river system). Aquatic biota plays an integral part in the functioning of aquatic ecosystems. Biological monitoring is used to assess ecosystem health and integrity. Biological communities reflect the overall integrity of the river ecosystem by integrating various stressors and therefore provide a broad measure of their synergistic effects. The research area falls within the Lower Vaal Water Management Area (WMA), which lies in the North-West and Northern Cape Provinces. The lower Vaal River and the Harts River (one of the tributaries of the Vaal) are the river systems under investigation in this study. Farming activities ranges from extensive livestock production and rain fed cultivation to intensive irrigation enterprises at Vaalharts (such as maize, cotton and groundnuts). The Vaalharts is the largest irrigation scheme in South Africa. Salinity is of concern in the lower reaches of the Harts- and Vaal Rivers, due to saline leachate from the Vaalharts irrigation scheme. Agricultural inputs are known to affect aquatic communities and chemicals (e.g. pesticides, herbicides, fertilizers) are extensively used in the Vaalharts irrigation scheme. At present there are no data on the effect of these chemicals on the aquatic biota of the lower Harts- and Vaal Rivers. The aims of this study were to assess the diatom- and macroinvertebrate community structures, ecosystem integrity and macroinvertebrate feeding traits (functional feeding groups – FFGs) in relation to land use.