Dissertations / Theses: 'Spatial distribution of heavy metals'

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Liberti, Michael F. "Spatial distribution of heavy metals in Center Township, Delaware County surface soils." Virtual Press, 1998. http://liblink.bsu.edu/uhtbin/catkey/1115430.

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Numerous urban soils surrounding industrial and metallurgical facilities in the U.S. are contaminated with metals including lead (Pb), cadmium (Cd), copper (Cu), Zinc (Zn), chromium (Cr), and nickel (Ni). Simplified geochemical mapping requires soil sampling and analysis for the presence of heavy metals from a grid pattern within a geographic area. In this study, a contour map of metal concentrations at two depths was subsequently superimposed over a standard political map to indicate areas of elevated metal concentrations in the soil. Natural levels of Pb, Cd, Cu, Zn, Cr, and Ni in Delaware County soils were determined to be 114.2 mg/kg, 0.14 mg/kg, 29.3 mg/kg, 88.4 mg/kg, 9.0 mg/kg, and 39.8 mg/kg, respectively. The average concentrations of metals found throughout Muncie, 203.9 mg/kg Pb, 39.2 mg/kg Cu, 275.4 mg/kg Zn, 9.7 mg/kg Cr, and 25.0 mg/kg Ni, were compared with natural levels to determine the extent of heavy metal pollution from atmospheric deposition. From the geographic mapping of metal concentrations, the effect of past industrial processes on possible contamination of soils by metals in Muncie, Indiana, was determined. Metals were also be fractionated in order to assess the percentage which is potentially bioavailable. Department of Natural Resources and Environmental Management

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Kampezidou, Dimitra. "Spatial distribution of heavy metals in surface marine sediments in the Mediterranean region." Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-111066.

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Several scientific articles were mainly reviewed from Umeå’ s university database in order to determine the distribution, degree of contamination, and the sources of 7 selected heavy metals (Cr, Pb, Cu, Zn, Cd, Hg, Ni) in surface sediments along the coasts of the Mediterranean Sea. The Enrichment factor (EF) was used as pollution indicator to evaluate the extent of metal contamination in all the investigated areas. According to Abrahim and Parker (2008) the EF is defined as the ratio of the determined metal to Al (or Fe) in the sample divided by the ratio of background metal to background Al (or Fe) ratio. According to the results of this study, EF values for Cr, Pb, Cu, Cd and Ni presented an upward trend along the west to east shoreline of the Mediterranean sea, whereas Zn and Hg EF values showed a downward trend along this region. Cr generally exhibited no enrichment in places to the west (EF<1.5) whereas in the eastern side displayed moderate enrichment (EF=1.95). Pb EF values showed moderate enrichment (EF=5) along the western section of the sea, whilst in the eastern part revealed significant enrichment (5.45). Zn pollution levels were minimal (EF=1.6) in places to the west and moderate (EF=2.2) to the east. The enrichment for Cd was considered moderate in the western part of the basin and significant in the eastern section. These heavy metals distribution can be explained by the fact that different inputs (mainly due to anthropogenic activities) from the inshore environment may take place in each area of the sea. However, Cu and Ni presented the same degree of pollution (moderate) in the whole sea, presumably indicating similar Cu and Ni inputs from the terrestrial environment. However, conclusions for Hg were not possible to be drawn as the collected data were not sufficient.

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Benamer, Mustafa Alarabi. "Chemical speciation and spatial distribution of heavy metals and their adsorption onto sediments of the Berg River, Western Cape, South Africa." Doctoral thesis, University of Cape Town, 2014. http://hdl.handle.net/11427/13167.

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Includes bibliographical references. The Berg River, Western Cape, South Africa, is an example of a catchment region where human pressures and conservation of natural resources collide. The river receives effluents from two large settlements and several smaller adjacent villages, including that of industrial and extensive agricultural activity. The estuary is one of the largest in South Africa and rated as the third most important conservation zone in the country. In this study, the chemical speciation of heavy metals in the river sediment was determined in order to evaluate the extent of pollution. Chemical speciation using sequential chemical extraction of sediment samples was used to measure the mobility and bioavailability of cadmium (Cd), lead (Pb), arsenic (As), chromium (Cr), nickel (Ni), cobalt (Co), iron (Fe), copper (Cu), zinc (Zn) and manganese (Mn). The metals Cd and Zn were found to be the most mobile and bioavailable. The study also examined the vertical distribution of heavy metals in estuarine sediment cores to evaluate the extent of heavy metal contamination with time and the degree to which heavy metals are influenced by other sedimentological parameters such as grain size, sediment composition and organic matter. Three sediment cores, ranging from 160 to 240 em long, were collected using a mechanical vibrating corer. The vertical distribution of metals in the cores showed that the metal concentration was higher at the top and middle of the cores. Based on the enrichment factor (EF) and anthropogenic factor (AF) values, it is suggested that the sediments of the estuary are not polluted with Co, Mn, Cu, Ni, Zn and Fe but moderately to highly polluted with Pb, As, Cd and Cr. The data reported provide a useful baseline for establishing heavy metal concentrations in the estuary and will be an important consideration in future sediment quality studies. The spatial distribution of the metals was also studied to understand how location is linked to metal concentration. The average concentration of metals in the core sediment increased with increasing distance from the mouth of the river. The adsorption behaviour of the estuary sediment with micro-pollutants has a significant influence on the environmental quality of estuary waters. For this reason, the absorption of Pb, Cr, Cu, Ni, and Zn onto sediment was study. It was found that the sediments of the Berg River estuary have a low potential for absorption of Ni and Zn making these metals more mobile and bioavailable.

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Al-Ibrahim, Zahid Omar Mustafa. "Investigation of pollution coming from copper, lead, and zinc mining, and factors controlling mobility and bioavailability of pollutants at Ecton Hill, Staffordshire, UK." Thesis, University of Wolverhampton, 2017. http://hdl.handle.net/2436/621722.

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Former mining areas are well-known globally to be a significant anthropogenic source of contaminants being dispersed into the surrounding environment. Various human activities, including ore mineral mining, industrial activities, domestic waste production, and the agricultural application of fertilisers and pesticides, are likely to contribute to the release of huge amounts of potentially toxic metals into the ecosystem, which have harmful effects on the flora and fauna and on human health. Therefore, the main aim of this study is to evaluate the contamination that arises from some selected heavy metals (Cu, Pb, Zn, Mn, Cr, Ni, and V) in topsoil and floodplain samples from the Ecton mining area. Ecton Hill is located in the southern part of the Peak District, Staffordshire, England, and bounded by the River Manifold from the west. This area has been mined for sulphide minerals, which were extracted extensively from the 16th century until the mid-19th century; the area is currently being used for cattle rearing and agricultural purposes. Therefore, it would be worth finding out the extent to which the area has been polluted by the aforementioned metals. To this end, topsoil and floodplain samples were collected and analysed for their total concentrations using XRF technique and different granulometric classes (i.e. clay, silt, and sand) using a (Malvern Mastersizer Long Bed) laser granulometer with a presentation unit of MS-17. In addition, soil specific factors, including organic matter content, organic carbon, pH, Eh, and cation exchange capacity were also measured. Spatial distribution maps were constructed using a GIS approach for the metals studied over the study area. Contamination and ecological risk assessments were carried out via the geoaccumulation index (Igeo) and enrichment factors (EF) respectively. Moreover, collected soils for different land uses have been assessed using the UK government soil guidelines (i.e. ICRCL and CLEA's SGVs soil values). Furthermore, the bioavailability, leachability, and fractionation (using five-steps sequential extraction) of the metals in various soil phases were characterised using correlation matrix and principal component analysis (PCA) approaches. The GIS- based spatial analysis maps reveal that elevated concentrations of the metals are located around the sites of the mining waste in the area. The contamination assessment results indicate that Cu, Pb, Zn have a contamination degree ranging between strongly contaminated (class 4) and extremely contaminated (class 6). The results of the ecological assessment by enrichment factor (EF) show that Pb has the highest enrichment factor. The bioavailability results of the heavy metals under study, via EDTA, show that Cu, Pb, Zn have the highest bioavailable fractions. The regression analysis demonstrates that Mn gives the best fit regression equation with the highest R2 value of 0.825. The leachability results reveal that, of the seven heavy metals, Zn has the highest leachable value, whereas the lowest leachable was recorded for Cr. Speciation was measured using the five-steps procedure, and the results show that Cu, Pb and Zn are mainly associated with the organic matter fraction, whilst, Cr, Ni and V are associated with the residual fraction. The principal component analysis (PCA) revealed that oxides of Fe/Al, organic matter, and the clay and silt fractions are the main soil parameters responsible for binding heavy metals to the soil surfaces of the study area. Changing the redox potential conditions and acidification was investigated and the results indicate that such changes have significant effects on the release of heavy metals from the soil particles at Ecton Hill.

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Andong, Omores Raissa. "Spatio-temporal distribution of polycyclic aromatic hydrocarbons (PAHs) in soils in the vicinity of a petrochemical plant in Cape Town." Thesis, Cape Peninsula University of Technology, 2016. http://hdl.handle.net/20.500.11838/2432.

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Thesis (MTech (Chemistry))--Cape Peninsula University of Technology, 2016. Polycyclic aromatic hydrocarbons (PAHs) are an alarming group of organic substances for humans and environmental organisms due to their ubiquitous presence, toxicity, and carcinogenicity. They are semi-volatile substances which result from the fusion of carbon and hydrogen atoms and constitute a large group of compounds containing two to several aromatic rings in their molecule. Natural processes and several anthropogenic activities involving complete or incomplete combustion of organic substances such as coal, fossil fuel, tobacco and other thermal processes, generally result in the release of the PAHs into the environment. However, the fate of the PAHs is of great environmental concern due to their tendency to accumulate and their persistence in different environmental matrices and their toxicity. Animal studies have revealed that an excessive exposure to PAHs can be harmful. Evidence of their carcinogenic, mutagenic, and immune-suppressive effects has been reported in the literature. In the soil environment, they have the tendency to be absorbed by plants grown on soil being contaminated by the PAHs. It is, therefore, important to evaluate their occurrence levels in different environmental matrices such as soil concentrations.

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FERNANDES-VANDERLEI, LAZARO. "Etude geochimique des sediments marins actuels d'une cote a plateau continental etroit : exemple des alpes maritimes." Nice, 1987. http://www.theses.fr/1987NICE4120.

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On etudie les sediments recents de l'interface dans la baie des anges, la baie de villefranche-sur-mer et dans la reserve sous-marine du larvotto au large de monaco, afin de mettre en evidence les relations existant entre les processus diagenetiques et lithologiques d'une part et les proprietes physico-chimiques des sediments d'autre part. On observe en particulier la qualite de la matiere organique presente dans l'eau et les sediments ainsi que les relations entre m. O. Ou ses produits de desintegration et les metaux-traces. On analyse les variations spatio-temporelles des teneurs en sels nutritifs et en metaux-traces, leur differenciation en fonction des conditions d'oxydo-reduction. On determine les facteurs dominants controlant les processus geochimiques

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Milton, Adrian Mark. "Heavy metals in contaminated grassland ecosystems : distribution, transfer and effects." Thesis, University of Liverpool, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266222.

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Napan, Katerine. "Distribution of Heavy Metals from Flue Gas in Algal Bioreactor." DigitalCommons@USU, 2014. https://digitalcommons.usu.edu/etd/4018.

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Algae are microscopic organisms with a great potential to produce biomass and lipids at productivities several times higher than terrestrial crops. To grow, these organisms consume carbon dioxide (CO2), a greenhouse gas. This gas, emitted primarily by power plants after coal burning, can be effectively used for algae production, thus resulting in CO2 remediation and biomass beneficial utilization as feedstuff, industrial filler and biodiesel feedstock. However, since coal is a fuel mined from the earth’s crust, it contains heavy metals that are released during coal burning and inevitably enter the algal cultivation system, contaminating the water were algae is grown, the algal biomass and the products derived from such biomass. The distribution of heavy metals from flue gas in algal cultivation systems is unknown, yet necessary to advance this industry. This study focused on quantifying the distribution and effects that ten coal-derived heavy metals (Cu, Co, Zn, Pb, As, Se, Cr, Hg, Ni and Cd) will have on algae strain Scenedesmus obliquus and on the potential products derived from this algae.

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Khandoker, Rafiqul Alam. "Distribution of Heavy Metals and Trace Elements in Soils of Southwest Oregon." PDXScholar, 1997. https://pdxscholar.library.pdx.edu/open_access_etds/4691.

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Soil samples from 118 sites on 71 geologic units in southwest Oregon were collected and analyzed to determine the background concentrations of metals in soils of the region. Sites were chosen in areas that were relatively undisturbed by human activities. The U.S. Environmental Protection Agency approved total-recoverable method was used to recover metals from samples for analysis. The twenty six metals analyzed were: Ag, AI, As, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, La, Li, Mg, Mn, Mo, Na, Ni, Pb, Sb, Se, Tl, V and Zn. The Klamath Mountains followed by the Coast Range contain the highest soil concentrations of AI, Ca, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Ni, V and Zn. Soils of the Coastal Plain and High Lava Plains contain the lowest concentrations of these metals. Unusually high soil As concentrations are found at two sites in the Klamath Mountains. All Be and Cd values above laboratory's reporting limits are also from the Klamath Mountains and Coast Range. Concentrations of soil Ba and La are fairly uniform throughout the region. Soil Pb levels are generally low with a few exceptions in the Klamath Mountains, Coast and Cascade Ranges. The region west of the Cascade Range has higher soil Hg contents than in the east. Soil metal concentrations are generally much higher in the region west of the Cascade Range, excluding the Coastal Plain, than in the east with the exception ofNa, because of more ultramafic rocks and a wetter climate. Soil metal concentrations are directly related to soil development with the highest concentrations being found in well developed Alfisols and Ultisols and the lowest concentrations in poorly developed Entisols. Most metals have similar averages and ranges of concentration compared to the rest of the United States (U.S.). Metals with high values compared to the rest of the U.S. are Cr, Co, Cu, Mn and Ni. In general, AI, Co, Cr, Cu, Fe, La, Li, Mg, Na, Ni, and V are concentrated in the B horizon while Ba, Ca, Hg, K, Mn, Pb and Zn are concentrated in the A horizon.

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Thums, Catherine Rosalie. "Geochemical associations and the spatial distribution of metals in urban soils." Thesis, Imperial College London, 2005. http://hdl.handle.net/10044/1/8625.

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Sancho, Maider. "The spatial distribution of metals in disc galaxies, via simulations and observations." Thesis, University of Central Lancashire, 2017. http://clok.uclan.ac.uk/20925/.

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In this thesis we are interested in the evoluNon of disc galaxies. One of the most common ways to study it is by a deep analysis of the distribuNon of chemical abundances in the stellar populaNons of the disc component. Abundance gradients let us reconstruct the puzzle of the formaNon and evoluNon of this type of galaxies, once we learn about the diﬀerent elements that are released to the interstellar medium at each stage of the life of stars. In this work we pay special aaenNon to the so-‐called thick disc component of spiral galaxies, believing that it is a relic of the early galaxy and its understanding opens the door for a complete galaxy formaNon scenario. We analyse thick discs both with observaNonal data and simulaNons because we want to have a wider view of the situaNon and we think that such complementary approaches can help us maximise our knowledge and results. Our simulaNons with an enhanced feedback are the ones that best reproduce the measured data from the Milky Way. The trend for the variaNon of the mean metallicity with galacNc radius at diﬀerent heights from the plane matches that in the Galaxy. It is negaNve in the mid-‐plane of galaxies and then becomes posiNve at greatest heights. According to simulaNons, this behaviour is due to a populaNon of relaNvely young and metal-‐rich stars formed in situ in the outer galaxy, which is missing in the inner thick disc. When looking at the same magnitudes but via observaNons from the CALIFA local universe galaxy sample, we see that the external galaxies exhibit a variety of diﬀerent behaviours both for the metallicity and age radial gradients with height, in addiNon to the trend found in simulaNons and the Milky Way. We deduce that thick discs probably do not form through a unique mechanism but from a combinaNon of many of them. Finally we want to know the inﬂuence of the galacNc mass in the chemical evoluNon of a disc galaxy. By using a ﬁducial set of simulaNons and comparing the results to observaNonal data we conclude that the smallest systems in our set might have an incorrect feedback eﬃciency, and suggest that a mass-‐dependent modulaNon of feedback might improve the result.

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Murphy, Louise Una. "Quantifying Spatial and Temporal Deposition of Atmospheric Pollutants in Runoff from Different Pavement Types." Thesis, University of Canterbury. Civil and Natural Resources Engineering, 2015. http://hdl.handle.net/10092/10467.

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Urban development leads to increased impermeable landscapes that interrupt the hydrological cycle by creating an impermeable barrier to the natural infiltration of precipitation. Precipitate, unable to infiltrate, flows over impermeable surfaces as sheet runoff, carrying the pollutants from the land with it; thus comprising the quality of the stormwater. The runoff is redirected (frequently untreated) to nearby waterways altering their water quality and quantity, thereby, adversely affecting receiving aquatic ecosystems. Suspended solids and elevated heavy metal concentrations in stormwater are the leading causes of water quality degradation in urban waterways in New Zealand. It is widely reported that vehicles and metal roofs are a major direct source of the key pollutants (total suspended solids (TSS) and heavy metals) in stormwater runoff; however, the contribution of atmospheric deposition, as an indirect source, in stormwater runoff is rarely considered. This is principally due to the many uncertainties and challenges with measuring and managing these pollutants in stormwater runoff. Therefore, a monitoring programme into the dynamics controlling atmospherically derived pollutant build-up and wash-off from urban surfaces was conducted. In particular, this research focused on the spatial and temporal variability of Cu, Zn, Pb, and TSS deposition in different land-use areas; the influence of pavement type on atmospherically-deposited pollutant loads in stormwater; and the contribution of wet deposition and dry deposition to the total deposition loads. Impermeable concrete boards (≈ 1 m2) were deployed for 11 months in different land-use areas (industrial, residential and airside) in Christchurch, New Zealand, to capture spatially distributed atmospheric deposition loads in runoff over varying meteorological conditions. Mixed-effect regression models were developed to explain the influence of different meteorological characteristics on pollutant build-up and wash-off dynamics. Next, impermeable asphalt, permeable asphalt, impermeable concrete, and permeable concrete boards were deployed for two months in a residential land-use area to determine the influence of pavement composition and roughness on pollutant loads in stormwater. Finally, wet deposition samples were analysed in an industrial land-use area for 8 months to monitor the contribution of wet deposition to atmospherically-deposited pollutant loads. All samples were analysed for total and dissolved Cu, Zn, Pb, and TSS. Pavement type: Results showed that both impermeable and permeable concrete were efficient at retaining Cu and Zn. Bitumen leaching from the impermeable asphalt was a significant source of Zn to runoff. However, bitumen leaching from the permeable asphalt did not contain elevated Zn loads. Infiltrate from the permeable asphalt provided little/no removal of Cu and Zn. Impermeable asphalt provided greater retention of TSS and Pb over impermeable concrete because its rougher surface entrapped more particulates. TSS and Pb loads were the lowest from the permeable pavements due to the pavers filtering out particulates. Spatial variability: Results showed that all three land-use areas exhibited similar patterns of varying metal and TSS loads, indicating that atmospherically-deposited metals and TSS had a homogenous distribution within the Christchurch airshed. This suggested that the pollutants originated from a similar source and that the surrounding land-use was not an important factor in determining atmospheric pollutant loads to stormwater runoff. Although, higher pollutant loads were found for the industrial area, this was attributed to local topographic conditions rather than land-use activity. Temporal variability: Results illustrated the importance of antecedent dry days on pollutant build-up. Peak rainfall intensity and rain duration had a significant relationship with TSS and Pb wash-off; rain depth had a significant relationship with Cu and Zn wash-off. This suggested that the pollutant speciation phase plays an important role in surface wash-off. Rain intensity and duration influenced particulate pollutants, whereas, rain depth influenced dissolved pollutants. Additionally, mixed-effect models could predict approximately 53-69% of the variation in airborne pollutant loads in runoff. Deposition pathways: Wet deposition was an important contributor of dissolved Zn to stormwater runoff. However, dry deposition was the greatest source of total Cu, Zn, and Pb loads in stormwater runoff. This is principally due to the low annual rainfall in Christchurch limiting pollutant removal via wet deposition unlike dry deposition, which is continually occurring. Understanding the dynamics of airborne pollutant deposition and their contribution to stormwater pollution could help stormwater managers in strategic decision-making processes such as choice of location and installation of different treatment systems.

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Åkerblom, Staffan. "Anthropogenic heavy metals in organic forest soils : distribution, microbial risk assessment and Hg mobility /." Uppsala : Department of Environmental Assessment, Swedish University of Agricultural Sciences, 2006. http://epsilon.slu.se/200667.pdf.

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14

Rappaport, Bruce D. "Availability and distribution of heavy metals from sewage sludge in the plant-soil continuum." Diss., Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/71177.

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An investigation was conducted using in situ lysimeters (1.5 m x 2.3 m) to determine Cd, Cu, Ni, and Zn availabilities for barley (Hordeum vulgare L.) and corn (Zea mays L.) grown on four sludge-amended soils. These lysimeters were constructed in Acredale silt loam (Typic Ochraqualf), Bojac loamy sand (Typic Hapludult), Davidson clay loam (Rhodie Paleudult), and Groseclose silt loam (Typic Hapludult) soils. An aerobically digested sewage sludge from a sewage system with major industrial inputs was applied at rates of 0, 42, and 84 dry Mg ha-t to the lysimeters in the poorly-drained Acredale soil. Rates of 0, 42, 84, 126, 168, and 210 dry Mg ha-1 were applied to the lysimeters in the well-drained Bojac, Davidson, and Groseclose soils. Tissue metal concentrations were determined in 1984 and 1985 for a three crop rotation, which consisted of corn, barley, and corn on the Acredale soil. Increases in sludge-borne Ni and Zn led to increases in Ni and Zn concentrations in corn earleaf, corn grain, and barley silage. Copper concentration was increased in barley silage but not in corn grain and stover. On this poorly-drained soil, metal movement did not occur below the Ap horizon even when Cu was applied in excess of USEPA guidelines. Although there were increases in metal levels, all four metals were within the range considered normal for corn and barley growth. Soil, corn, and barley plants were sampled in 1984 and 1985 to determine Cd, Cr, Cu, Ni, and Zn availabilities for crops grown on the sludge-amended Bojac, Davidson, and Groseclose soils. Levels of DTPA-extractable Cd, Cu, Ni, and Zn in the Ap horizon of these soils increased linearly with sludge rate. Corn grain and stover yields were not decreased on the Bojac, Davidson, and Groseclose soils when 4.5, 5105, 760, 43.0, 135, and 620 kg ha-1 of Cd, Cr, Cu, Ni, Pb, and Zn were added as a sludge-amendment. Copper and Zn applied in excess of 480 and 60 kg ha- 1 of USEPA guidelines, respectively on the Bojac, Davidson, and Groseclose soils were not phytotoxic to corn plants in 1984. Corn and barley tissue sampled for three consecutive seasons had Cr concentrations <2.8 mg kg-1. Ph. D.

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Reid, Miriam Katherine. "An Investigation of the Spatial Distribution and Partitioning of Metals in Estuarine Sediments." Thesis, Queen Mary, University of London, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.499283.

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Brady, James P. "Heavy metals in the sediments of Northern Moreton Bay, Queensland, Australia." Thesis, Queensland University of Technology, 2015. https://eprints.qut.edu.au/89686/6/89686%28thesis%29.pdf.

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This project was the first comprehensive assessment of heavy metals to be conducted in the sediments of Northern Moreton Bay since the 1970s and found that shipping and shipping related activities contributed significantly to the level of sediment contamination in the area. The study was also used to develop and test new methods of assessing heavy metal sediment quality.

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Jordan, Suzanne Louise. "The distribution and geochemical fractionation of heavy metals in anthropogenically-polluted soils and soil phases." Thesis, University of Bristol, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390378.

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Brown, Rachel. "The sub-surface distribution of some heavy metals following sewage sludge injection into grassland soils." Thesis, University of Plymouth, 1994. http://hdl.handle.net/10026.1/2079.

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The use of suitable sewage sludge in agriculture is currently its cheapest disposal option, both in terms of monetary cost, resource utilisation and environmental impact Monitoring of die heavy metal content of the soil after sludge application is required by European Council Du-ective 86/278/EEC, and whilst the behaviour of metals from surface-applied sludge is well documented, the behaviour following other methods of application has received litde attention. The most important alternative land application method cturentiy in use is the subsurface injection of sludge. In this project, field- and laboratory-based experiments were set up to describe the postinjection disttibution of Cd, Cu, Ni, Pb and Zn and the effect on this of: tine design (using die straight tine, side-inclined tine and winged tine), rate of injection (225 m^ ha'-^ and 300 m3 ha"-^), and soil factors ^ H , cation exchange capacity, organic carbon, percentage clay,. Fe and Mn concentration, and redox potential). An assessment of the variability of die injection operation was also important, as account needs to be made of metal distribution and variability in order to delimit an appropriate sampling regime. The results of these experiments indicated that Cu, Pb and Zn are basically immobile, remaining widiin 120 mm of die centte of die original slot location. Tine design was seen to have a significant influence on the pattern of subsurface metal distribution, but neither this,' rate of injection nor soil factors adequately predicted die extent of diis distiibution. Instead, metal identity and concentration widiin the sludge were identified as the most influential factors, in that appreciable quantities of Cd and Ni are leached out of the profile to distances exceeding 300 mm from die sludge, and greater metal concentirations (of the remaining metals) in the injected sludge create distinct gradients in the soil and saturates exchange sites, thus promoting mobility via diffusion, over-riding normal metal chemistry. Of those measured variables that had a secondary effect on distribution, pH, Fe oxide concentration and percentage clay were identified as the most important soil factors.The winged tine was seen to promote soil disturbance and hence metal distribution, and the paraplow to restrict both. In practical terms, these conclusions indicate that the current sampling protocol is inadequate. An alternative regime is suggested.

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Luo, Chen. "Distribution and mobilization of heavy metals at an acid mine drainage-affected region, South China." Thesis, Linköpings universitet, Tema Miljöförändring, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-163084.

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Dabaoshan Mine Site (DMS) is the biggest polymetallic mine in South China. The Hengshi River receives acid mine drain (AMD) waste leaching from the tailings pond and run-off from the treatment plant which flows into the Wengjiang River, Beijiang River, before discharging into the Pearl River. Discharge from the mine site results in heavy metal contamination near the mine and lower riparian areas along the river course. The present study focuses on the distribution and mobilization of As, Cd, Pb and Zn along the Hengshi River, groundwater, fluvial sediments and soil, with a special focus on As due to its high toxicity and the fact that mining is one of the main anthropogenic sources of As. Heavy metals, grain-size, XRD, %C and S analysis were done in order to determine the physicochemical characteristics of samples. The results were used for geochemical modeling (PHREEQ) and statistical (PCA) analysis to understand and predict the behavior of heavy metals. Potential ecological risk assessment was conducted by calculating contamination degree of heavy metals in soil and sediment and it’s theoretical toxical risk. Near the tailings pond, heavy metal concentration was 2-100 times higher than chinese surface water standard for agricultural use, which decreases downstream, mianly due to dilution, sorption, precipitation and co-precipitation with minerals. In groundwater, heavy metals concentration remained low. Due to the fact that most wells were abandoned or only for household use, potential risk from groundwater is low. The soils were disturbed by industrial or agricultural activities, and heavy metal concentration varied without showing any specific trend along the river. The potential ecological risk of heavy metals are ranked as: Cd>As>Cu>Pb>Zn in sediments; Cd>Cu>Pb>As>Zn in soil. As(Ⅲ) was the predominant species in surface water, and minerals identified in soil and sediment. Arsenic from most sites exceeded the Chinese soil standard for development land. Although arsenic was assumed to have a moderate ecological risk in sediments and low risk in soils, anthropogenic activities, such as land use change and untreated sewage discharge, might reduce and release arsenic into the environment, which poses potential risk to local residents.

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Gaber, Noha. "Development of a mechanistic model to assess the distribution of heavy metals in municipal wastewater treatment." Thesis, University of Southampton, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342771.

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Finale, Carolina. "Distribution of heavy metals in the Antarctic marine environment: possible relationships between aerosol, seawater and phytoplankton." Doctoral thesis, Università Politecnica delle Marche, 2015. http://hdl.handle.net/11566/242944.

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Abstract Distribuzione dei metalli pesanti in ambiente Antartico marino: possibili relazioni tra aerosol, acqua di mare e fitoplancton Il progetto del mio lavoro di dottorato ha riguardato lo studio della distribuzione dei metalli pesanti Cd, Pb e Cu in ambiente antartico marino (mare di Ross), in particolare nell’aerosol marino, nell’acqua di mare e nel fitoplancton. La presenza di metalli pesanti nel sistema marino antartico, in particolar modo di metalli tossici come Pb e Cd, dipende da diversi fattori, tra i quali il più importante è la deposizione con l’aerosol. I metalli pesanti adsorbiti sulle particelle di aerosol, possono venire trasportati per lunghe distanze e, una volta raggiunta la superficie degli oceani, passano nella matrice acquosa. Una volta entrati nella matrice acquosa, la loro distribuzione verticale e orizzontale è controllata dalla loro interazione con il particellato sospeso lungo la colonna d’acqua. In particolare, la distribuzione dei metalli può essere influenzata dalla componente algale del particellato. Lo studio della distribuzione dei metalli in tracce nel fitoplancton è quindi un requisito importante per capire come questa fase può influenzare la distribuzione dei metalli nell’acqua di mare e, di conseguenza, i cicli biogeochimici marini di un elemento. Lo studio ha previsto il raggiungimento di diversi obiettivi: i) Analisi quali-quantitativa della componente fitoplantonica nel Mare di Ross antistante la stazione italiana “Mario Zucchelli”, campionata durante l’estate australe 2011-2012; ii) messa a punto di una metodologia analitica per la determinazione di Cd, Pb, Cu nel fitoplancton; iii) messa a punto di una tecnica analitica per la determinazione di Cd, Pb, Cu nell’aerosol; iv) studio della distribuzione di Cd, Pb e Cu in acqua di mare tra componente disciolta, particellata e algale. I gruppi di fitoplancton maggiormente presenti sono le Diatomee e le Dinoflagellate. L’abbondanza e la densità aumentano durante l’estate australe raggiungendo i massimi valori a metà gennaio e febbraio. La messa a punto della separazione del fitoplancton dal particellato non algale, che prevede la separazione fisica utilizzando un microscopio ottico invertito, è risultato essere un buon metodo per la separazione del micro-fitoplancton. La successiva messa a punto della digestione del campione di fitoplancton al microonde (necessaria per l’analisi voltammetrica) ci ha permesso di determinare la quota di metalli pesanti legata al fitoplancton. Abbiamo dimostrato che la frazione algale del particellato può variare notevolmente in rapporto al periodo di campionamento e alla profondità. La separazione fisica del fitoplancton dal particellato inorganico ci ha permesso di effettuare determinazioni accurate dei metalli pesanti legati esclusivamente alla componente algale e di poter quindi studiare l’influenza del fitoplancton sulla distribuzione dei metalli pesanti in acqua di mare. La tecnica analitica ottimizzata per la determinazione di Cd, Pb e Cu nell’aerosol (Square Wave Anodic Stripping Voltammetry), ha previsto lo studio del comportamento elettrochimico dei metalli e lo studio della caratterizzazione voltammetrica del sistema. Una volta ottimizzata, questa tecnica analitica è stata applicata con successo per la determinazione sistematica di Cd, Pb e Cu sui campioni di aerosol. In particolare, si sono determinate la frazione solubile, associata all’aerosol marino, estraibile, associata all’attività antropica locale ma e/o all’attività biogenica marina, ed inerte, di origine crostale. I dati relativi alle concentrazioni dei metalli pesanti nel fitoplancton, associati ai dati della concentrazione totale, disciolta e particellata di Cd, Pb e Cu nell’acqua di mare e la distribuzione dei metalli nell’aerosol permettono l’investigazione dei cicli biogeochimici di questi elementi. Abstract Distribution of heavy metals in the Antarctic marine environment: possible relationships between aerosol, seawater and phytoplankton The project of my PhD involved the study of the distribution of heavy metals Cd, Pb and Cu in marine Antarctic environment (Ross Sea), in particular in marine aerosol, seawater and phytoplankton. The presence of heavy metal in seawater, in particular toxic metals such Pb and Cd, depends on many input, among which the most important is the deposition of aerosol. Heavy metals adsorbed onto aeolian particles can be transported over long distances and when these particles reach the surface of oceans, the associated elements pass into the upper water masses. Once they enter the water matrix, their vertical and horizontal distributions are controlled by their interaction with particulate material suspended in water column. In particular, the distribution can be influenced by the algal component of the particulate. The study of the distribution of trace elements in the phytoplankton is a requisite for investigating the marine biogeochemical cycles of the elements. The study needed to achieve different objectives: i) quali-quantitative analysis of phytoplankton present in the Ross Sea (near “Mario Zucchelli” Italian station) during austral summer 2011-12; ii) optimization of an analytical methodology for the determination of Cd, Pb and Cu in phytoplankton; iii) optimization of an analytical technique for the determination of Cd, Pb and Cu in aerosol; iv) study of the distribution of Cd, Pb and Cu between dissolved, particulate and algal fractions. The most prevalent groups of phytoplankton are Diatoms and Dinoflagellates. Both abundance and density increase during austral summer reaching maximum values in January and February. The optimization of the physical separation of phytoplankton from non-algal particulate using an inverted optical microscope, proved to be an excellent method for the separation of micro-phytoplancton. The optimization of the microwave digestion to make the sample suitable for voltammetric analysis, allowed us to determine the quotas of heavy metals associated to phytoplankton. We demonstrated that the fraction of algal component in the particulate phase can varies considerably depending on the sampling period and on the depth. The physical separation of phytoplankton from inorganic particulate allow us to perform accurate measurements of heavy metals linked exclusively to algal component and study the influence of phytoplankton on the heavy metal distribution in seawater. The optimized analytical technique for the determination of Cd, Pb and Cu in the aerosol samples (Square Wave Anodic Stripping Voltammetry) concerned the study of electrochemical behaviour of the metals and the study of voltammetric characterization of the system. Once optimized, this analytical technique was applied for the systematic determination of Cd, Pb and Cu in the aerosol samples. In particular, we determined the soluble fraction of heavy metals, associated to marine aerosol, extractable fraction, associated to the local antrophic activity and/or to the biogenic marine activities, and inert fraction, lied to the crustal origin. Data relative to heavy metals concentration in phytoplankton, associated to data about total, dissolved and particulate seawater concentration of Cd, Pb and Cu and aerosol distribution of metals permit an investigation of the biogeochemical cycles of these elements.

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Magno, Melissa A., Ingrid Luffman, Arpita Nandi, and Brian G. Evanshen. "SPATIAL INTERPOLATION OF HEAVY METAL CONCENTRATIONS IN SOILS OF BUMPUS COVE, TN." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/asrf/2018/schedule/126.

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Mining processes generate waste rock, tailings, and slag that can increase heavy metal concentrations in soils. Un-reclaimed, abandoned mine sites are particularly prone to leaching these contaminants, which may accumulate and pose significant environmental and public health concerns. The characterization and spatial delineation of heavy metals of such soils is vital for risk assessment and soil reclamation. Bumpus Cove, once one of the richest mineralized districts of eastern TN, is home to at least 47 abandoned, un-reclaimed mines that were all permanently closed by the 1950s. This study evaluated 52 soil samples collected within a 0.67 km2 study area containing 6 known abandoned Pb, Zn, and Mn mines at the headwaters of Bumpus Cove Creek for heavy metal concentrations. Soil samples were analyzed for Zn, Mn, Pb, Cu, and Cd by means of microwave-assisted acid digestion and flame atomic absorption spectrometry (FAAS). Using the measured values and digital elevation model (DEM) derived from lidar data, ordinary kriging and cokriging interpolation techniques were used to predict the trend of heavy metal concentrations throughout the study area. Concentrations for Zn, Mn, and Pb show significant variability between sample sites (ranges of 12 – 1,354 mg/kg Zn, 6 – 2,574 mg/kg Mn, 33 – 2,271 mg/kg Pb). Cu and Cd were much less variable, with ranges of 1 - 65 mg/kg and 7 – 40 mg/kg, respectively. Of the measured heavy metals, only Zn and Pb exceed permissible limits in soils. Results show that ordinary kriging interpolation methods produced improved results over ordinary cokriging with and without lognormal transformations for all metals. Mn and Pb were found to transport further downhill following the natural drainage, whereas Zn, Cu and Cd concentrations exhibit localized variability without a clear transportation path. This study can provide a reference for state and local entities responsible for heavy metal monitoring in Bumpus Cove, TN.

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Diouf, Aissatou. "Effect of Organic Amendments on Heavy Metal Distribution and Uptake in Vegetable Gardens in Senegal." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/73036.

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The major constraints to food production in West Africa are related to the lack of suitable lands. Consequently, farmers incorporate organic amendments and wastewater to improve their yields. Within some limits, such wastes enhance soil fertility and can improve its physical properties. However, the advantages of using organic waste as fertilizer and soil amendment should be assessed with possible environmental and toxicological impacts due to the potential presence of heavy metals. The objective of this study was to assess the effect of organic amendments on heavy metal distribution in soils and vegetables in market gardens in Senegal. Organic amendments and soils samples were collected from four sites in eastern and southern Senegal. Samples were analyzed for physicochemical properties including particle size, total heavy metals, carbon content, nutrients, and pH. A sequential extraction procedure was conducted to determine heavy metal sinks. Results showed that sites were sandy in nature, low to medium in organic carbon content (8300 to 36600 mg kg-1), and had pH ranging from 5 to 7.9. The sequential extraction procedure showed that metals were distributed in the more stable soil fractions: Fe-Mn oxide, organic and residual. The highest soil metal concentrations in soils were found in Pikine and Rufisque sites. Plant samples were collected from these two sites and analyzed for total metal content. Results showed that all metal concentrations in soils, organic amendments, and vegetables were within the safe limits proposed by the World Health Organization, with the exception of Cd, Pb and Zn levels in vegetables. Master of Science

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McConway, Alex. "The effects of trace metals on juvenile cockles (Austrovenus stutchburyi)." Thesis, University of Canterbury. Biological Sciences, 2008. http://hdl.handle.net/10092/1696.

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This thesis investigated the population structure and spatial distribution of the cockle Austrovenus stutchburyi in estuaries and bays around the Canterbury coastline. Surveys investigated population attributes (average density and density of small cockles (< 10mm)) of Austrovenus stutchburyi in relation to physical environmental characteristics such as trace metals (copper, cadmium and zinc), sediment particle size, nitrogen and phosphorus levels, pore water and percentage organic matter of the sediment. Surface cover of flora and number of fauna present was also correlated with the density of cockles and small cockles < 10mm. MDS and PCA ordination showed that the biota was similar at 14 sites but differed significantly at the Pleasant Point Yacht Club (PPY) site. There was a positive correlation between fine sand (125 μm) and the average density of cockles and small cockles < 10 mm. High population densities of Austrovenus stutchburyi were also positively correlated with phosphorus levels, and percentage cover of Sea Grass (Ulva sp). However, Austrovenus stutchburyi density was negatively correlated with cadmium and zinc concentration, and percentage of mud present. The density of small cockles < 10 mm was negatively correlated with copper and cadmium concentration in the sediment and positively correlated with Topshell (Diloma subrostrata) numbers, Sea grass (Zostera muelleri) percentage cover, Sea lettuce (Ulva sp), percentage cover, and sediment particles sizes of < 63 μm (mud), 63 μm (very fine sand), and 125 μm (fine sand). Survival and behavioural changes of juvenile Austrovenus stutchburyi were investigated in relation to increased levels of copper, cadmium, and zinc in aqueous solution and sediment in the laboratory, and artificially increased levels in the field. In laboratory experiments in contaminated seawater it was found that, over time, copper and zinc had a detrimental effect on the percentage of juvenile cockles with their siphons extended as did copper concentration. Cockles 10 - 12 mm shell length exposed to different concentrations of copper had the lowest survival rate (25%) whilst cockles that were 5 - 7 mm in length had the greatest survival rate (69%). Cadmium did not affect survival or siphon extension in aqueous experiments. In the contaminated sediment experiments in the laboratory, the concentration of zinc (0, 20, 40, 80, 160 mg Zn/kg (dry weight)) and cadmium (0, 1.8, 5.6, 18, 36 mg Cd/kg (dry weight)) both decreased survival and burial of juvenile cockles in higher concentrations. Copper concentration (0, 5, 10, 25, 50 mg Cu /kg (dry weight)) decreased burial rates of juvenile cockles but did not affect survival. Transfer of juvenile Austrovenus stutchburyi within three sites in the Avon Heathcote Estuary during May 2007, found that site and exposure to copper, cadmium and zinc decreased the survival of the juvenile cockles. However, transfer of cockles between estuaries (Takamatua, Saltwater Creek and Avon – Heathcote Estuary) in May 2007 found that exposure to copper, cadmium and zinc had the main effect on survival of juvenile cockles. In July 2007 transfers of cockles between estuaries, site and exposure to copper, cadmium and zinc had an effect of survival on juvenile cockles. Cockle populations in the present research have shown a strong correlation with environmental variables, which can be used for management and conservation. The research in this thesis is a start to understanding the effects and implications of contaminants on survival, behaviour and recruitment of juvenile cockles. This research will benefit management strategies for increasing population numbers of Austrovenus stutchburyi.

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Sultan, Khawar University of Ballarat. "Distribution of arsenic and heavy metals in soils and surface waters in Central Victoria (Ballarat, Creswick and Maldon)." University of Ballarat, 2006. http://archimedes.ballarat.edu.au:8080/vital/access/HandleResolver/1959.17/12767.

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"Three sampling campaigns were conducted in the Ballarat, Creswick and Maldon areas. The sampling area is part of the Golden Triangle region where significant gold-mining activities took place from the 1850s to the present day. [...] Locations were chosen to evaluate arsenic distribution in soils, surface waters and plants in different environments. Easy access to sampling locations allowed detailed scientific sampling, especially in the seasonality study. The different range of environments such as agricultural, state forest, mining, urban and rural provided an opportunity to compare the concentrations of arsenic and other elements in the study area. The study of the three selected areas combined provided further understanding of possible exposure and pathways through which arsenic can get into the food chain. "The objective of the study is to measure levels of heavy metals/metalloids in soils, water and plants in various environments, identify whether the heavy metals/metalloids are mobile and bioavailable and understand the importance of clays and oxide complexes in the fixation of metals." Doctor of Philosophy (PhD)

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Sultan, Khawar. "Distribution of arsenic and heavy metals in soils and surface waters in Central Victoria (Ballarat, Creswick and Maldon)." Thesis, University of Ballarat, 2006. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/32792.

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"Three sampling campaigns were conducted in the Ballarat, Creswick and Maldon areas. The sampling area is part of the Golden Triangle region where significant gold-mining activities took place from the 1850s to the present day. [...] Locations were chosen to evaluate arsenic distribution in soils, surface waters and plants in different environments. Easy access to sampling locations allowed detailed scientific sampling, especially in the seasonality study. The different range of environments such as agricultural, state forest, mining, urban and rural provided an opportunity to compare the concentrations of arsenic and other elements in the study area. The study of the three selected areas combined provided further understanding of possible exposure and pathways through which arsenic can get into the food chain. "The objective of the study is to measure levels of heavy metals/metalloids in soils, water and plants in various environments, identify whether the heavy metals/metalloids are mobile and bioavailable and understand the importance of clays and oxide complexes in the fixation of metals." Doctor of Philosophy (PhD)

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Sultan, Khawar. "Distribution of arsenic and heavy metals in soils and surface waters in Central Victoria (Ballarat, Creswick and Maldon)." University of Ballarat, 2006. http://archimedes.ballarat.edu.au:8080/vital/access/HandleResolver/1959.17/15387.

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"Three sampling campaigns were conducted in the Ballarat, Creswick and Maldon areas. The sampling area is part of the Golden Triangle region where significant gold-mining activities took place from the 1850s to the present day. [...] Locations were chosen to evaluate arsenic distribution in soils, surface waters and plants in different environments. Easy access to sampling locations allowed detailed scientific sampling, especially in the seasonality study. The different range of environments such as agricultural, state forest, mining, urban and rural provided an opportunity to compare the concentrations of arsenic and other elements in the study area. The study of the three selected areas combined provided further understanding of possible exposure and pathways through which arsenic can get into the food chain. "The objective of the study is to measure levels of heavy metals/metalloids in soils, water and plants in various environments, identify whether the heavy metals/metalloids are mobile and bioavailable and understand the importance of clays and oxide complexes in the fixation of metals." Doctor of Philosophy (PhD)

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28

Paveley, C. F. "Heavy metal sources and distribution in soils, with special reference to Wales : Background ranges, threshold concentrations and sources of lead, zinc, copper, cadmium, cobalt, nickel, manganese and iron in A and B soil horizons." Thesis, University of Bradford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233744.

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Dilks, Caroline Frances. "Spatial variation and behaviour of heavy metals (Pb and Zn) in the urban soils of north-central Newcastle, Tyneside." Thesis, Northumbria University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323471.

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Groves, Sarah Anne Biological Earth &amp Environmental Sciences Faculty of Science UNSW. "Spatial and temporal variation in the hydrochemistry of marine prawn aquaculture ponds built in acid sulfate soils, Queensland, Australia." Publisher:University of New South Wales. Biological, Earth & Environmental Sciences, 2008. http://handle.unsw.edu.au/1959.4/43273.

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Many brackish water aquaculture ventures in Australia and overseas have established ponds in coastal regions with acid sulfate soils (ASS). Acid sulphate soils are known to leach relatively high concentrations of metals, acid (metal and H+ ion) and sulfur, however very little is known about how these leached elements affect the water quality of aquaculture ponds. The main objective of this thesis was to describe the hydrochemical processes controlling the water chemistry in the water column and sediment pore water in the studied aquaculture ponds over time and space. Water samples providing the spatio-temporal data were collected from the ponds with the use of adapted sampling methods commonly used in the groundwater environment. A transect of five nested piesometers was installed in two prawn ponds at Pimpama, south east Queensland, Australia. Each piesometer nest contained a multilevel with eight outtakes, a mini ?? horizontal, and a slotted piesometer. Water samples were collected from each nested piesometer on a bi-monthly basis over the prawn-growing season. The unstable elements and water quality variables (pH, Eh, DO, EC, water temperature) were measured in the field. Stable elements were analysed in the laboratory using ICP-OES and ICP-MS. Soil samples were collected at the end of the season for elemental analysis. A number of key sediment/water interactions and processes such as precipitation/dissolution reactions, oxidation-reduction reactions, photosynthesis, adsorption and seawater buffering were identified as important controls on pond water conditions. This is the first study to provide detailed hydrochemcial analysis of the pond water over time and space and aided in identifying that even shallow water bodies can be chemically heterogeneous. Analysis of the water and sediment highlighted the selection of metals that can be associated with ASS and that are mobilised from pond sediments under certain chemical conditions. In Pond 7 Al, As, Ni and Zn concentrations were generally higher at the beginning of the grow-out season. Variability of the metal concentration was observed between the water column (0 ?? 1500 mm) and the pore-water (0 - -1000 mm). The highest concentration of Al (1044 ??g/L) and Zn (104 ??g/L) were sampled in the water column (approximately 400 mm from the surface of the pond). The highest concentration of As (130 ??g/L) and Ni (73 ??g/L) were sampled in the pore water sediment (associated with ASS). Elevated Mn and Fe2+ concentrations were also associated with the sediment pore water. The highest concentrations of Mn and Fe2+ were 4717 ??g/L and 5100 ??g/L respectively. In Pond 10, Ni concentrations (167 ??g/L) were the highest at the beginning of the grow-out season. However, As (97 ??g/L), Al (234 ??g/L) and Zn (308 ??g/L) were most concentrated during the middle of the cycle. The highest mean concentrations of these elements are As (63 ??g/L), Al (91 ??g/L) and Zn (69 ??g/L) which are each associated with the sediment-water interface. These metals are integral in degrading the pond water quality and lead to a loss of beneficial algal blooms, a reduction in pond water pH, poor growth rates and high mortality in shrimp. It is also possible that the dissolved ions and precipitated compounds that are leached from the ASS are discharged into the adjacent coastal estuary of Moreton Bay. With knowledge obtained from this PhD study, effective management and treatment systems can be developed and implemented to minimise the impact of these soils on the pond system and the water discharging into natural coastal ecosystem.

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Wu, Chuan. "Effects of radial oxygen loss (ROL) on arsenic tolerance, uptake and distribution by rice (Oryza sativa L.)." HKBU Institutional Repository, 2011. http://repository.hkbu.edu.hk/etd_ra/1246.

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Raulinaitis, Mindaugas. "Effects of Hydromechanical Lake Remediation on Distribution of Metals and Metalloids in Bottom Sediments." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2012. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2012~D_20121227_090648-54420.

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Although hydromechanical lake remediation projects have been carried out over several decades, there still is a lack of evidence about the changes in environmental status after such projects, while scientific literature regarding redistribution of metals and metalloids caused by hydromechanical bottom sediment removal is especially scarce both in Lithuania and in other countries. Research of the dissertation consisted not only of extensive geochemical field work and laboratory analysis, but also methods of mathematical statistics and spatial interpolation. Results of the research and their analysis allowed to conclude that hydromechanical lake remediation results in changes of the contents of metals and metalloids of interest and their spatial redistribution in lake bottom sediments, which are specific to each metal and metalloid, thus cumulative indicators should be used to assess overall changes in sediment quality of remediated lakes. Calculation and statistical analysis of on of such indicators - total sediment contamination index (Zd) and surface interpolation of its values allowed to evaluate statistical significance of changes in contamination degree of the newly formed surface sediment layer and to assess cumulative spatial redistribution of metals and metalloids caused by hydromechanical lake remediation. Data provided in the dissertation is especially significant in preparation and design of future sediment removal projects and in determining their feasibility. Nors hidromechaninio ežerų valymo darbai vykdomi jau daugelį metų, iki šiol nėra aišku, kaip pasikeičia ežero aplinkosauginė būklė po jo išvalymo, o Lietuvos ir kitų šalių mokslinėje literatūroje informacijos apie valymo sąlygotus metalų ir metaloidų pasiskirstymo dugno nuosėdose pokyčius yra stebėtinai mažai. Disertacijos tyrime buvo taikoma kompleksinė šių pokyčių vertinimo sistema, pasitelkiant ne tik išsamius geocheminius lauko ir laboratorinius tyrimus, bet ir matematinę statistinę analizę bei erdvinę duomenų prognozę ir interpoliaciją. Tyrimų ir analizės rezultatai parodė, kad hidromechaninis ežero valymas sąlygoja nagrinėjamų metalų ir metaloidų kiekių pokyčius ir jų persiskirstymą dugno nuosėdose, kuris yra savitas atskiriems cheminiams elementams, todėl siekiant nustatyti valymo darbų įtaką būtina naudoti indikatorius, leidžiančius įvertinti bendro, kumuliacinio nuosėdų užterštumo lygio pokyčius visų nagrinėjamų elementų atžvilgiu. Vieno iš tokių indikatorių – suminio užterštumo rodiklio Zd verčių statistinė analizė ir erdvinė interpoliacija leido ne tik nustatyti statistiškai patikimą hidromechaninio ežero valymo įtakotą metalų ir metaloidų pokyčių reikšmingumą naujai susiformavusiame paviršiniame dugno nuosėdų sluoksnyje, bet ir pademonstruoti erdvinį šių elementų perskirstymą dugno paviršiaus plote. Disertacijoje pateikiama informacija yra ypač aktuali vertinant Lietuvos ežerų būklę, planuojant ežerų dugno nuosėdų šalinimo darbus ir nustatant jų tikslingumą.

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Chatter-Singh, Davene Naomi. "Spatial and temporal analysis of heavy metals in surface waters, bed sediments and suspended sediments of the River Stour, East Kent, U.K." Thesis, University of Greenwich, 2008. http://gala.gre.ac.uk/8393/.

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A baseline study has been undertaken to assess the environmental impact of heavy metals within the fluvial environment of the River Stour, E. Kent, U.K. The occurrence of metal enrichment in surface waters and bed sediments coincides mainly with areas of urbanisation and high density traffic in addition to point source discharges including STW and industrial effluent outlets. Non-tidal surface water samples exhibiting Pb, Co, Cu, Fe and Zn concentrations intermittently elevated above EQS List I and II values largely correspond with bed sediment samples exhibiting metal concentrations above background values and commonly partitioned to the mobile exchangeable/acid soluble and reducible fractions. In the tidal reaches surface water samples exhibiting As, Cd, Co, Cu, Cr, Ni, Pb, V and Zn concentrations above EQS List I and II values are generally associated with bed sediment samples exhibiting partitioning to the immobile oxidisable fraction, suggesting that estuarine processes effectively promote the liberation of elements from the sediment compartment to surface waters. Total catchment annual suspended sediment yield, (190 t/km2/yr), is consistent with previous research work detailing the annual yield of U.K. rivers which in conjunction with suspended sediment concentration data highlights the importance of the transport and distribution of associated elements throughout the river system. Research highlights a requirement to improve point source management measures and control non-point sources and dredging activities and provides an index in which to assess the future impact of anthropogenic sources of metals to the fluvial environment of the River Stour.

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Theodory, Ronnie George. "The distribution of stable isotopes and heavy metals in Dreissena polymorpha (zebra mussel), chemical tracers for environmental contamination in Lake St. Clair." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0009/MQ52747.pdf.

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Snyman, Reinette Georgenie. "The uptake and distribution of selected heavy metals in the freshwater crab, Potamonautes perlatus (Milne Edwards), in the Eerste River, Western Cape." Thesis, Stellenbosch : University of Stellenbosch, 1996. http://hdl.handle.net/10019.1/1630.

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Thesis (MScAgric (Zoology))--University of Stellenbosch, 1996. A number of studies on the general physico-chemical character of the Eerste River, Western Cape, had previously been done, but the problem of heavy metal pollution had, by 1993, not been addressed. A study was therefore undertaken from 1993-1995 in order to investigate these aspects. Since several researchers have shown that freshwater crabs accumulate certain heavy metals in their bodies and may therefore be used as monitors of environmental heavy metal pollution, the present study concentrated mainly on metal concentrations (Mn, Zn, Cu, Pb and Cd) in the local freshwater crab species, Potamonautes perlatus, and its possible use as biomonitor in the Eerste River. Two localities in the Eerste River were chosen,. in order to make comparisons, namely a relatively uncontaminated site in the Assegaaibosch Nature Reserve, Jonkershoek, and a visibly polluted site downstream from Stellenbosch, behind Stellenbosch Farmers' Winery (SFW). Crabs, water and sediment samples were collected seasonally at both localities, and metal concentrations thereof determined by atomic absorption spectrophotometry. The results showed that the Eerste River down to the SFW locality is still relatively unpolluted in terms of heavy metals. It was, however, clear that runoff from the Stellenbosch municipal, industrial and agricultural areas do have an influence on other physico-chemical features of the river. The concentrations of heavy metals in whole crabs, tissues and carapace showed that Zn concentration was well regulated in P. perlatus from both localities, Mn and Cu were accumulated in individuals from SFW, and Pb and Cd accumulated in both populations. Compartmentalization of heavy metals was shown to occur in P. perlatus: the carapace was found to be the most important storage site for Mn, Zn and Pb, the carapace and gonads equally important for Cd storage, and the digestive gland the most important site for Cu storage. Whereas gender was shown, generally, to be of little importance in heavy metal uptake in P. perlatus, crab body size and seasonality were both shown to influence heavy metal uptake to some extent. However, only summer peaks in whole crab, carapace and tissue manganese concentrations were shown to correlate with peaks in environmental Mn concentrations. It was concluded that P. perlatus would possibly only be a Suitable monitor of environmental Mn, Pb and Cd pollution, although there is no guarantee that the crab body would accurately reflect environmental concentrations. It was also ascertained that, since a study of the sperm ultrastructure of P. perlatus showed a significantly larger number of abnormal spermatozoa in male crabs from ,SFW, and since these observed differences could possibly be related to heavy metal exposure, the sperm of this species might be a more reliable indicator of heavy metal pollution. It was finally concluded that more intensive research need to be undertaken on various aspects, especially the use of the spermatozoon as indicator of environmental heavy metal pollution, and that the results of the present study could serve as a basis for future studies.

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Olujimi, Olanrewaju Olusoji. "The concentrations, distribution and health risk assessment of suspected endocrine disrupting chemicals (phenols, phthalates and heavy metals) in freshwater systems of Cape Town, South Africa." Thesis, Cape Peninsula University of Technology, 2012. http://hdl.handle.net/20.500.11838/2009.

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Thesis (DTech (Environmental Health))--Cape Peninsula University of Technology, 2012. Environmental pollution with persistent organic chemicals and inorganic trace metals is an increasingly important issue. Recently, a variety of chemicals are introduced in a very large scale on the surface water network. The main pathway of these pollutants into the environment was identified as wastewater treatment plants (WWTPs). The extended use of chemicals in many product formulations and insufficient WWTPs has lead to an increase in the levels of the detected micro-pollutants wastewater effluents. The majority of these compounds are characterized by a rather poor biodegradability. A large spectrum of pollutants present in waste as traces has been reported to exert adverse effects on human and wildlife. Even though compounds are found in wastewater in a very small amount, they may have the undesirable capability of initiating health effect on various high forms of life. This survey constitutes the first study in the City of Cape Town to report data for a variety of priority substances (phenols and phthalate esters) in WWTP effluents and receiving rivers. These results are of critical importance since the data generated are used to generate potential health risk associated with both the organic and inorganic compounds analyzed.

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Soares, Marcio Roberto. "Coeficiente de distribuição (Kd) de metais pesados em solos do estado de São Paulo." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/11/11140/tde-31052005-170719/.

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A disposição de resíduos sólidos e a aplicação de pesticidas e fertilizantes podem levar ao aumento da concentração de metais pesados em solos e águas subterrâneas. A legislação sobre metais pesados quase sempre se refere aos seus teores totais, mas a avaliação do potencial de risco e da toxicidade requer a avaliação da proporção de metal que é móvel e, possivelmente, biodisponível. Alguns parâmetros numéricos têm sido utilizados para tomadas de decisões e para direcionar estratégias de prevenção ou de remediação de áreas contaminadas. O coeficiente de distribuição sólido-solução (Kd), definido como a relação entre as concentrações adsorvida e em solução, permite a comparação do comportamento de elementos em diferentes sistemas. Agências de proteção ambiental utilizam valores genéricos de Kd encontrados em referências bibliográficas que, por terem sido gerados a partir de condições distintas das da região tropical, podem levar a incorretas estimativas de risco. É evidente a necessidade da obtenção de valores de Kd que validem estas estimativas de contaminação ou que norteiem estratégias de intervenção em áreas já contaminadas. Os objetivos deste trabalho foram avaliar a retenção de metais pesados em 30 solos representativos do Estado de São Paulo, a partir da quantificação dos valores do coeficiente de distribuição (Kd) e da relação com atributos dos solos, tais como pH, CTC e teores de argila, matéria orgânica e de diversas formas de óxidos de Fe, Al e de Mn. Os coeficientes de distribuição foram obtidos de isotermas lineares de adsorção, construídas após a adição de 0,1; 0,5; 1,0; 2,5 e 5,0 mg L-1 de Cd, Co, Cr, Cu, Ni, Pb e Zn, em experimentos tipo batch. As menores variações nos valores de Kd foram registradas para o Pb (uma ordem de magnitude 121 a 7.020 L kg-1) e para o Ni (duas ordens de magnitude - 6 a 998 L kg-1), enquanto variações de quatro ordens de magnitude foram observadas para Cd (7-14.339 L kg-1), Co (2-34.473 L kg-1) e para Cr (1-21.267 L kg-1). Coeficientes de distribuição de zinco estiveram entre 5 a 123.849 L kg-1, variando cinco ordens de magnitude. Os valores foram similares àqueles que vêm sendo utilizados pela CETESB, exceto os de Cr e Ni. Obteve-se a seguinte ordem de afinidade: Pb>>>Cu>>Cd>Zn≅Ni≅Cr>Co. Mais de 55% da variação dos coeficientes de distribuição de cátions metálicos dos grupos IIB (Cd e Zn) e VIIIB (Co e Ni) foram explicados pelo pH. Na análise conjunta, CTC e pH explicaram cerca de 80% da variação dos valores de Kd de Cd, Co e de Ni e evidenciaram que mecanismos de adsorção não-específica estão envolvidos na retenção destes elementos. No caso dos coeficientes de distribuição de Cu e de Pb, o pH e os teores de argila responderam por cerca de 63% da sua variação. Os valores de Kd de Cr apresentaram correlação inversa com o pH, principalmente na análise conjunta com os teores de argila, e 61% da sua variação foi explicada por estas variáveis. Disposal of solid residues and application of pesticides and fertilizers can lead to an increase in the concentration of heavy metals in soils and groundwater. The legislation on heavy metals nearly always refers to the total contents of these elements; however, an evaluation of their hazard potential and toxicity requires an assessment of the metal fraction that is mobile and possibly bioavailable. A few numerical parameters have been used as a foundation to make decisions and to focus on prevention or remediation strategies in contaminated areas. The solid-solution distribution coefficient (Kd), defined as the relation between metal concentrations that are adsorbed and those present in the solution, allows a comparison between the behavior of elements in different systems. Environmental protection agencies use generic Kd values found in bibliographic references; these values are often obtained under distinct conditions from those found in the tropical region, and may lead to an erroneous hazard estimates. Thus, it becomes clearly necessary to obtain Kd values that will validate these contamination estimates or provide guidance for intervention strategies in already contaminated areas. The objectives of this work were to evaluate heavy metal retention in 30 representative soils of the State of São Paulo, based on a quantification of distribution coefficient values (Kd) and their relation with soil attributes, such as pH, CEC and clay contents, organic matter, and various forms of Fe, Al, and Mn oxides. The distribution coefficients were obtained from linear adsorption isotherms, constructed after the addition of 0.1; 0.5; 1.0; 2.5; and 5.0 mg L-1 Cd, Co, Cr, Cu, Ni, Pb, and Zn, in batch-type experiments. The smallest variations in Kd value were recorded for Pb (one order of magnitude 121 to 7,020 L kg-1) and Ni (two orders of magnitude - 6 to 998 L kg-1), while variations indicating four orders of magnitude were observed for Cd (7-14,339 L kg-1), Co (2 - 34,473 L kg-1), and Cr (1 - 21,267 L kg-1). Zinc distribution coefficients were between 5 and 123,849 L kg-1, with a variation of five orders of magnitude. The values herein obtained were similar to those that have been used by CETESB, except for Cr and Ni. The following order of affinity was obtained: Pb>>>Cu>>Cd>Zn≅Ni≅Cr>Co. More than 55% of the variation in distribution coefficients for metallic cations of the groups IIB (Cd and Zn) and VIIIB (Co and Ni) were explained by pH. In the joint analysis, CEC and pH explained about 80% of the variation in Kd values for Cd, Co, and Ni, and showed that nonspecific adsorption mechanisms are involved in the retention of these elements. Regarding the distribution coefficients for Cu and Pb, pH and clay content accounted for about 63% of the variation. Kd values for Cr showed an inverse correlation with pH, especially in the joint analysis with clay contents, and 61% of the variation were explained by these variables.

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Moral, Cigdem. "Production Of Alginate From Azotobacter Vinelandii And Its Use In Water And Wastewater Treatment." Phd thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12612919/index.pdf.

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Alginates are copolymers of &beta -D-mannuronic (M) and &alpha -L-guluronic acids (G). In this study, Azotobacter vinelandii ATCC&reg 9046 was used to produce alginate in a fermentor. The effect of parameters such as dissolved oxygen tension (DOT), agitation speed, initial concentrations of sucrose and calcium on the properties of alginate were examined. Changes of DOT in the range of 1 and 10 % affected alginate production. The optimum DOT giving high alginate yield (4.51 g/L) and maximum viscosity was observed as 5 % yielding moderate GG-blocks of 55 %. Both high and low agitation levels reduced alginate production, but these conditions increased GG-block alginates as 76 and 87 % at 200 and 700 rpm, respectively. Moderate sucrose and calcium concentrations, 20 g/L and 50 mg/L, respectively were found better since further increase in their concentrations did not lead to a considerable improvement in alginate production and quality. Sodium alginates produced in this work were investigated for maximum heavy metal uptake with a special focus on copper ion and the highest copper uptake was around 1.9 mM Cu2+/g alginate. Findings showed that the block distribution of alginate was not as important as expected for copper removal. Alginate together with calcium ions was used for the removal of turbidity. The amount of GG-block was found to be important in turbidity removal. Alginate having 55 % GG block and 8.9 cP viscosity resulted in a final turbidity lower than 1 NTU at 2 mg/L of alginate with 60 mg/L of calcium ion.

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Raulinaitis, Mindaugas. "Hidromechaninio ežerų valymo įtaka metalų ir metaloidų pasiskirstymui dugno nuosėdose." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2012. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2012~D_20121227_090639-11076.

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Nors hidromechaninio ežerų valymo darbai vykdomi jau daugelį metų, iki šiol nėra aišku, kaip pasikeičia ežero aplinkosauginė būklė po jo išvalymo, o Lietuvos ir kitų šalių mokslinėje literatūroje informacijos apie valymo sąlygotus metalų ir metaloidų pasiskirstymo dugno nuosėdose pokyčius yra stebėtinai mažai. Disertacijos tyrime buvo taikoma kompleksinė šių pokyčių vertinimo sistema, pasitelkiant ne tik išsamius geocheminius lauko ir laboratorinius tyrimus, bet ir matematinę statistinę analizę bei erdvinę duomenų prognozę ir interpoliaciją. Tyrimų ir analizės rezultatai parodė, kad hidromechaninis ežero valymas sąlygoja nagrinėjamų metalų ir metaloidų kiekių pokyčius ir jų persiskirstymą dugno nuosėdose, kuris yra savitas atskiriems cheminiams elementams, todėl siekiant nustatyti valymo darbų įtaką būtina naudoti indikatorius, leidžiančius įvertinti bendro, kumuliacinio nuosėdų užterštumo lygio pokyčius visų nagrinėjamų elementų atžvilgiu. Vieno iš tokių indikatorių – suminio užterštumo rodiklio Zd verčių statistinė analizė ir erdvinė interpoliacija leido ne tik nustatyti statistiškai patikimą hidromechaninio ežero valymo įtakotą metalų ir metaloidų pokyčių reikšmingumą naujai susiformavusiame paviršiniame dugno nuosėdų sluoksnyje, bet ir pademonstruoti erdvinį šių elementų perskirstymą dugno paviršiaus plote. Disertacijoje pateikiama informacija yra ypač aktuali vertinant Lietuvos ežerų būklę, planuojant ežerų dugno nuosėdų šalinimo darbus ir nustatant jų tikslingumą. Although hydromechanical lake remediation projects have been carried out over several decades, there still is a lack of evidence about the changes in environmental status after such projects, while scientific literature regarding redistribution of metals and metalloids caused by hydromechanical bottom sediment removal is especially scarce both in Lithuania and in other countries. Research of the dissertation consisted not only of extensive geochemical field work and laboratory analysis, but also methods of mathematical statistics and spatial interpolation. Results of the research and their analysis allowed to conclude that hydromechanical lake remediation results in changes of the contents of metals and metalloids of interest and their spatial redistribution in lake bottom sediments, which are specific to each metal and metalloid, thus cumulative indicators should be used to assess overall changes in sediment quality of remediated lakes. Calculation and statistical analysis of on of such indicators - total sediment contamination index (Zd) and surface interpolation of its values allowed to evaluate statistical significance of changes in contamination degree of the newly formed surface sediment layer and to assess cumulative spatial redistribution of metals and metalloids caused by hydromechanical lake remediation. Data provided in the dissertation is especially significant in preparation and design of future sediment removal projects and in determining their feasibility.

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40

Syrovetnik, Kristina. "Long-term metal retention processes in a peat bog : Field studies, data and modelling." Doctoral thesis, Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-460.

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41

Milenija, Marković. "Model unapređenja ekološkog statusa zatvorenog sistema vodnih tela akumulacija." Phd thesis, Univerzitet u Novom Sadu, Fakultet tehničkih nauka u Novom Sadu, 2015. https://www.cris.uns.ac.rs/record.jsf?recordId=95401&source=NDLTD&language=en.

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Eksperimentalnim istraživanjem u okviru doktorske teze utvrđen je trend promene fizičko-hemijskih parametara: mutnoća, temperatura, provodljivost i pH vode, koncentracija katjona Cd2+, As3+, Hg2+ i Pb2+, ukupnog azota, fosfora i sulfatnog ajona u vodi i sedimentu, na lokalitetu Zapadne Srbije, slivno područje akumulacije Vrutci u 2003/2014. Rezultati istraživačkih aktivnosti predstavljali su osnovu za razvoj regresionog modela kojim se može predvideti koncentracija katjona teških metala u jezerskoj vodi. Primenom klaster analize, dendograma i PCA analize dobijena su tri faktora na osnovu kojih se posmatra uticaj ključnih fizičko-hemijskih parametara na kvalitet vode zatvorenog vodnog tela akumulacije pri čemu su dobijene visoko korespodentne funkcionalne zavisnosti sa realnim podacima u jezeru. Ovakva istraživanja su po prvi put sprovedena za selektovani lokalitet u Srbiji. Experimental studies in the doctoral thesis established the trend of changes in the physico-chemical parameters: turbidity, temperature, conductivity and pH of the water, the concentration of cations Cd, As, Hg and Pb, total nitrogen, phosphorus and sulphate anion in water and sediment at the site of Western Serbia, the catchment area of the reservoir Vrutci in 2003/2014. Results of research activities constituted the basis for the development of a regression model which can predict the concentration of heavy metal cations in lake water. Cluster analysis, dendograms and PCA (principal component analysis) were resulted by three factors, which could be possible to registre the impact of key physical and chemical parameters on the water quality of the closed lake reservoirs.The obtained results by multivariance analysis has showen the highly correspondent functional dependence with real data in a lake. Such research investigations were for the first time carried out in selected localities in Serbia.

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Šindelářová, Anna. "Analýza zubů a kostí metodou spektroskopie laserem buzeného plazmatu." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2021. http://www.nusl.cz/ntk/nusl-445149.

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The presented diploma thesis deals with the elemental composition of hard tissues – human and murine jaws studied by laser-induced plasma spectroscopy (LIBS). Samples of human teeth contained a disease called ankylosis and the difference in elemental composition of healthy and diseased tissue was observed to localize ankylosis in the tooth. When evaluating the map of the spatial distribution of phosphorus and calcium, a decrease in the concentration of these elements in the ankylosis infected area was observed. Furthermore, murine jaws containing lead were analyzed. When assessing the spatial distribution of lead in tissue, it was found that lead was incorporated in murine teeth in the enamel at the tip of the incisor and molars. In conclusion, LIBS method achieved good results considering the detection of the elemental distribution of hard tissues. It enables to differentiate parts of the tooth in terms of elemental composition and tissue hardness and also to detect changes in the matrix caused by a disease or bioaccumulation of heavy metals.

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Liu, Xintao. "The Principle of Scaling of Geographic Space and its Application in Urban Studies." Doctoral thesis, KTH, Geodesi och geoinformatik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-90832.

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Geographic space is the large-scale and continuous space that encircles the earth and in which human activities occur. The study of geographic space has drawn attention in many different fields and has been applied in a variety of studies, including those on cognition, urban planning and navigation systems. A scaling property indicates that small objects are far more numerous than large ones, i.e., the size of objects is extremely diverse. The concept of scaling resembles a fractal in geometric terms and a power law distribution from the perspective of statistical physics, but it is different from both in terms of application. Combining the concepts of geographic space and scaling, this thesis proposes the concept of the scaling of geographic space, which refers to the phenomenon that small geographic objects or representations are far more numerous than large ones. From the perspectives of statistics and mathematics, the scaling of geographic space can be characterized by the fact that the sizes of geographic objects follow heavy-tailed distributions, i.e., the special non-linear relationships between variables and their probability. In this thesis, the heavy-tailed distributions refer to the power law, lognormal, exponential, power law with an exponential cutoff and stretched exponential. The first three are the basic distributions, and the last two are their degenerate versions. If the measurements of the geographic objects follow a heavy-tailed distribution, then their mean value can divide them into two groups: large ones (a low percentage) whose values lie above the mean value and small ones (a high percentage) whose values lie below. This regularity is termed as the head/tail division rule. That is, a two-tier hierarchical structure can be obtained naturally. The scaling property of geographic space and the head/tail division rule are verified at city and country levels from the perspectives of axial lines and blocks, respectively. In the study of geographic space, the most important concept is geographic representation, which represents or partitions a large-scale geographic space into numerous small pieces, e.g., vector and raster data in conventional spatial analysis. In a different context, each geographic representation possesses different geographic implications and a rich partial knowledge of space. The emergence of geographic information science (GIScience) and volunteered geographic information (VGI) greatly enable the generation of new types of geographic representations. In addition to the old axial lines, this thesis generated several types of representations of geographic space: (a) blocks that were decomposed from road segments, each of which forms a minimum cycle such as city and field blocks (b) natural streets that were generated from street center lines using the Gestalt principle of good continuity; (c) new axial lines that were defined as the least number of individual straight line segments mutually intersected along natural streets; (d) the fewest-turn map direction (route) that possesses the hierarchical structure and indicates the scaling of geographic space; (e) spatio-temporal clusters of the stop points in the trajectories of large-scale floating car data. Based on the generated geographic representations, this thesis further applies the scaling property and the head/tail division rule to these representations for urban studies. First, all of the above geographic representations demonstrate the scaling property, which indicates the scaling of geographic space. Furthermore, the head/tail division rule performs well in obtaining the hierarchical structures of geographic objects. In a sense, the scaling property reveals the hierarchical structures of geographic objects. According to the above analysis and findings, several urban studies are performed as follows: (1) generate new axial lines based on natural streets for a better understanding of urban morphologies; (2) compute the fewest-turn and shortest map direction; (3) identify urban sprawl patches based on the statistics of blocks and natural cities; (4) categorize spatio-temporal clusters of long stop points into hotspots and traffic jams; and (5) perform an across-country comparison of hierarchical spatial structures. The overall contribution of this thesis is first to propose the principle of scaling of geographic space as well as the head/tail division rule, which provide a new and quantitative perspective to efficiently reduce the high degree of complexity and effectively solve the issues in urban studies. Several successful applications prove that the scaling of geographic space and the head/tail division rule are inspiring and can in fact be applied as a universal law, in particular, to urban studies and other fields. The data sets that were generated via an intensive geo-computation process are as large as hundreds of gigabytes and will be of great value to further data mining studies. QC 20120301 Hägerstrand project entitled “GIS-based mobility information for sustainable urban planning and design”

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Aleksandra, Mihailović. "Fizičke karakteristike zemljišta i distribucija teških metala na gradskom području Novog Sada." Phd thesis, Univerzitet u Novom Sadu, Prirodno-matematički fakultet u Novom Sadu, 2015. https://www.cris.uns.ac.rs/record.jsf?recordId=94955&source=NDLTD&language=en.

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Uzorci zemlji&scaron;ta iz pov&scaron;inskog sloja dubine 0 - 10 cmprikupljeni su sa 121 lokacije na gradskom području NovogSada. Ispitivano područje obuhvatilo je povr&scaron;inu (4 x 5)km2,koja je podeljena na mrežna polja veličine (400 x 400) m2 i u          svakom polju uzet je po jedan uzorak. Za 121 uzorakgradskog zemlji&scaron;ta Novog Sada ispitana su fizičko-hemijskasvojstva zemlji&scaron;ta, ukupni i pristupačni sadržaj metala (As,Co, Cr, Cu, Mn, Ni, Pb, Zn) i njihova prostorna raspodela.Konturne mape prostorne raspodele metala u zemlji&scaron;tudobijene su kori&scaron;ćenjem interpolacijske metode običnogkriginga. Za pojedine uzorke izvr&scaron;eno je razdvajanje česticapo veličinama frakcionisanjem u vodi pomoću sita različitihveličina i identifikovani su minerali prisutni u frakciji prah +glina. Aktivnosti radionuklida &bdquo;unsupported” 210Pb i 137Csodređene su za jedan deo uzoraka zemlji&scaron;ta u Novom Sadu iza uzorke zemlji&scaron;ta pored fabrike akumulatora u Somboru.Ispitana je i vertikalna distribucija stabilnog i radioaktivnogPb u zemlji&scaron;tu.Na 14 lokacija u Novom Sadu prikupljeno je 35 uzorakasnega direktno sa asfaltnih puteva i sa zemljanih povr&scaron;ina uokolini puteva i na pe&scaron;ačkim ostrvima. Raspodela čestica poveličinama i ukupne koncentracije metala (Al, Ca, Cu, Fe, K,Na, Mn, Ni, Pb, Zn) određene su analizom filtriranih uzoraka,a za 4 uzorka ispitana je morfologija čestica i urađenasemikvantitativna analiza čestica u suvoj materiji.Prilikom obrade rezultata merenja primenjene su metodedeskriptivne statistike i multivarijacione statističke analize ucilju identifikacije izvora zagađenja i određivanja povezanostiizmeđu samih metala i drugih parametara. A total of 121 surface soil samples were collected across the central part of Novi Sad covering a surface area (4 km x 5 km). The physicochemical properties, pseudo total and available metal concentrations (As, Co, Cr, Cu,  Mn, Ni, Pb, and Zn) were determined. Contour maps of spatial distribution of the investigated metals were obtained using ordinary  kriging interpolation method. Separation of different particle size fractions by wet sieving  and identification of minerals in the clay and silt fraction for some soil samples were performed.  Specific activities of radionuclides “unsupported” 210Pb and 137Cs were measured in forty soil samples collected in urban area of Novi Sad and industrial area of Sombor (near a battery manufacturer).  Vertical distribution of stable and radioactive  Pb for  two samples from the industrial soil was examined.Thirty five snow samples were collected at fourteen locations near crossroads in Novi Sad. The samples were taken directly from the road surface and from the ground surface in the vicinity of roads and on pedestrian islands. Particle size distribution and  total concentration of the metals (Al, Ca, Cu, Fe, K, Na, Mn, Ni, Pb, Zn) were  determined for filtered samples. Semi-quantitative analysis of the particles was  conducted and morphology of the particles was examined for dry matter of four snow samples. Methods of descriptive and multivariate statistics and geostatistics were carried out for  the analysis and interpretation of the data.

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45

SANTOS, DIOGO F. dos. "Caracterização dos campos neutrônicos obtidos por meio de armadilhas de nêutrons a partir da utilização de água pesada (D2O) no interior do núcleo do reator nuclear IPEN/MB-01." reponame:Repositório Institucional do IPEN, 2015. http://repositorio.ipen.br:8080/xmlui/handle/123456789/23825.

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Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-07-23T11:04:17Z No. of bitstreams: 0 Made available in DSpace on 2015-07-23T11:04:17Z (GMT). No. of bitstreams: 0 Dissertação (Mestrado em Tecnologia Nuclear) IPEN/D Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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Colombàs, Borràs Margalida. "Nivells d'elements traça i macroelements als sòls de les Illes Balears." Doctoral thesis, Universitat de les Illes Balears, 2014. http://hdl.handle.net/10803/663752.

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[cat] S'estudia l’estat actual del contingut de set macroelements (Ca, Mg, Al, Fe, K, Na i P) i nou elements traça (As, Cd, Co, Cr, Cu, Mn, Ni, Pb i Zn) en els sòls de les Illes Balears. A partir de la determinació del contingut total de macroelements i elements traça mitjançant la digestió de les mostres de sòl per via humida amb aigua règia i s’estudien les relacions que hi ha entre ells i amb les característiques fisicoquímiques del sòl. També s’estudia el comportament dels elements en funció de l’illa, la profunditat i a una sèrie de sòls representatius de les Illes Balears. Finalment, s’estableix una proposta de nivells de fons i valors de referència dels elements traça a les Illes Balears comparant diferents mètodes, amb la finalitat de poder tenir criteris que permetin identificar una possible alteració dels continguts d’aquests elements. Els continguts medians (mg kg-1) obtinguts pels elements traça estudiats a les mostres superficials han estat: As 15,8, Cd 0,42, Co 9,6, Cr 57,3, Cu 18,7, Mn 467,1, Ni 29,3, Pb 18,7, Zn 53,9. Respecte el comportament en funció de l’illa, el Cd, Co, Cr, Cu, Mn, Ni, Pb i Zn presenten valors més baixos de concentració a Formentera i els més alts a Menorca, amb situacions intermèdies a les altres dues illes, més semblants a Menorca en el cas de Mallorca i més semblants a Formentera en el cas d’Eivissa. L’As no presenta diferències de concentració entre illes. Aquest comportament dels elements traça és invers al del CCE i del pH, així, llocs on tenen un contingut elevat de carbonats tenen un baix contingut d’elements traça. Les correlacions entre la majoria de paràmetres estudiats són significativament altes (p<0,05) o molt altes (p<0,001). Tot i això, els coeficients dels llims, CO, pH, Na, P i Mg amb la resta de paràmetres són relativament baixos, indicant un baix efecte d’aquests paràmetres sobre els elements traça. Les relacions entre l’Al, Fe, K, As, Cd, Co, Cr, Cu, Mn, Ni, Pb i Zn són altament significatives i presenten majoritàriament coeficients positius elevats entre ells, suggerint un origen comú i natural d’aquests. Pel que fa l’estudi dels elements traça sobre sòls representatius de les Illes Balears s’ha observat que sobre materials calcaris, els sòls menys diferenciats presenten els continguts més baixos d’elements traça i els més evolucionats són els que presenten els continguts més elevats. Per ordre, els continguts més baixos corresponen als Arenosols de sistemes dunars litorals, seguits de Cambisols sobre margues, Calcisols, Cambisols sobre margues i, finalment, Luvisols com a tipologies més diferenciades i amb continguts d’elements traça més elevats. D’altra banda, sobre les roques olivíniques del Keuper es desenvolupen sòls amb alts continguts de P, Fe, Co, Cr, Mn i Ni i baixos de Cd. Els rangs de concentració (mg kg-1) de la població de fons dels diferents elements traça per als sòls de les Illes Balears amb el mètode del gràfic de probabilitat han estat: As 2,5-28,2, Cd 0,03-0,74, Co 1,7-16,9, Cr 12,9-95,3, Cu 2,6-32,6, Mn 53,3-793,5, Ni 5,5-49,6, Pb 0,3-34,7, Zn 9,6-96,4. Els valors mitjans de la població de fons han resultat molt semblants amb els cinc mètodes utilitzats. Tot i això, s’aprecia que el rang més ampli de població de fons, i per tant el valor de referència més alt, s’ha obtingut amb el mètode del diagrama de caixes, seguit dels mètodes del rang normal d’una mostra, del de la funció de la distribució calculada, del mètode del gràfic de probabilitat i, per acabar, del mètode de la mediana, amb el que s’obté el rang més estret, i per tant del valor de referència més baix. [spa] Se han investigado 508 perfiles de las Islas Baleares y la variabilidad en ellos de los niveles de macroelementos (Ca, Mg, Al, Fe, K, Na i P), elementos traza (As, Cd, Co, Cr, Cu, Mn, Ni, Pb i Zn) y algunas propiedades del suelo (arenas, limos, arcillas, carbonato cálcico equivalente -CCE-, carbono orgánico, pH y capacidad de intercambio catiónico). Los puntos de muestreo seleccionados presentaban una mínima influencia antropogénica y las muestras de suelo fueron recogidas para cada horizonte de cada perfil. Para el análisis de macroelementos y elementos traza las muestras fueron digeridas usando agua regia y horno microondas. Las concentraciones medias de elementos traza (mg kg-1) obtenidas en horizontes superficiales fueron: As 15,8, Cd 0,42, Co 9,6, Cr 57,3, Cu 18,7, Mn 467,1, Ni 29,3, Pb 18,7, Zn 53,9. Los resultados obtenidos del análisis estadístico revelan correlaciones significativas entre la mayoría de elementos y el contenido de CCE, arcillas y materia orgánica, indicando que las concentraciones de estos elementos se encuentran controladas por las características del suelo. La concentración de elementos traza es relativamente baja en áreas con elevado contenido de CCE, así la concentración de carbonatos en el suelo es un factor determinante en la presencia y distribución de elementos traza en los suelos del área estudiada. Con respecto a la profundidad, se observa un incremento del contenido de arcillas y pH al aumentar ésta y una disminución de la materia orgánica. Respecto los elementos traza, el Cu, Pb Cd, Mn y Zn presentan una disminución en función de la profundidad, mientras que el As, Co, Cr i Ni no presentan diferencias significativas entre los horizontes comparados. Por lo que se refiere a los suelos desarrollados en cada grupo de referencia se encontraron claras diferencias: sobre calcáreas, los suelos poco desarrollados presentan las concentraciones más bajas de elementos traza, mientras que los suelos diferenciados presentan las mayores concentraciones. En orden ascendente de concentración, el menor contenido corresponde a Arenosols de sistemas dunares litorales, seguidos por los Cambisols sobre margas, Calcisols, Cambisols sobre margas y, finalmente, Luvisols como la tipología más diferenciada y con el mayor contenido de elementos traza. Por otro lado, en suelos desarrollados sobre rocas olivínicas del Keuper aparecen altos contenidos de P, Fe, Co, Cr, Mn y Ni y bajas concentraciones de Cd. Por último se estableció la concentración de niveles de fondo y de referencia. Los valores de referencia obtenidos a partir de gráficos de probabilidad fueron(mgkg): As 28,2, Cd 0,74, Co 16,9, Cr 95,3, Cu 32,6, Mn 793,5, Ni 49,6, Pb 34,7, Zn 96,4. [eng] In this work, 508 soil profiles of Balearic Islands (European Mediterranean region) were investigated, and the variability in the levels of major elements (Ca, Mg, Al, Fe, K, Na i P), trace elements (As, Cd, Co, Cr, Cu, Mn, Ni, Pb i Zn) and some soil properties (sands, silts, clays, calcium carbonate equivalent -CCE-, organic carbon, pH and cation exhange capacity) was examined. Sampling sites with minimal antrhropogenic influence were selected and soil profile samples were analysed for major and trace element content. The soil samples were collected from every horizon in each profile and the samples were digested using aqua regia and microwave oven for pseudo-total trace elements. The median concentrations of trace elements (mg kg-1) obtained in surface horizons were: As 15.8, Cd 0.42, Co 9.6, Cr 57.3, Cu 18.7, Mn 467.1, Ni 29.3, Pb 18.7, Zn 53.9. The results obtained from the statistical analysis reveal significant correlations between most elements and CCE, clay and organic matter contents, indicating that metal concentrations are controlled by soil composition. The trace element concentration is relatively low in areas of high CCE, therefore carbonate concentration in soil is the determining factor in the presence and distribution of trace elements in the soils of the studied area. According to depth, Cu, Pb, Cd, Mn and Zn show an increase with depth, in the same way of clays and pH. As, Co, Cr and Ni do not show statistical differencies between horizons. A clear distinction was found between the metal content of the soils developed in each Reference Soil Group: Over limestones, poor-developed soils show the lowest concentrations of trace elements while well-developed soils have the highest concentrations. In ascending order of concentration, the lowest content correspond to Arenosols of litoral dune systems, followed by Cambisols over marls, Calcisols, Cambisols over marls and, finally, Luvisols as most differenciated tipologies and with higher trace element contents. On the other hand, over Keuper olivinic rocks soils with high concentrations of P, Fe, Co, Cr, Mn and Ni and low concentrations of Cd are developed. The background concentration and reference values have also been stablished. The reference values obtained in this study through probability plots were (mgkg): As 28.2, Cd 0.74, Co 16.9, Cr 95.3, Cu 32.6, Mn 793.5, Ni 49.6, Pb 34.7, Zn 96.4.

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47

ROGER, BERTRAND. "Repartition et localisation des metaux traces dans les sediments : application a l'estuaire de la loire." Nantes, 1987. http://www.theses.fr/1987NANT2021.

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La premiere partie methodologique porte sur la validite des schemas de mineralisations selectives actuels. La comparaison de deux schemas permet de mettre en evidence l'importance des readsorptions en cours de mineralisation sur les phases encore presentes. Il est necessaire de conserver a l'echantillon toute son integrite lors des attaques effectuees pour determiner la disponibilite vraie des metaux. La deuxieme partie traite du comportement des metaux lies au sediment dans l'estuaire de la loire. La covariance des teneurs en metaux avec la granulometrie et le carbone organique reste bonne tout au long de l'estuaire et les speciations ne font pas etat d'evolutions notables de repartitions lors du transit estuarien

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Cheng, Bai-You, and 鄭百佑. "Estimating Spatial Distribution of Heavy Metals in Soil." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/12257077974194451289.

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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 By combination of the semi-variogram of Kriging Method with Fuzzy theory, in order to set up a Membership Function, and the new spatial interpolation method was named Fuzzy Estimate. It has a clear principle, simple in structure, provides more flex adjusted with more reasonable physics phenomenon. By applying this new interpolation method, the spatial distribution of heavy metal in soil can be predicted more precisely. By comparison Fuzzy Estimate with the ordinary Kriging Method, Radial Basis Function(RBF) and the other three traditional spatial interpolation Methods. Such as the Inverse Distance Weighted(IDW), Global Polynomial Interpolation(GPI),Local Polynomial Interpolation (LPI).To evaluate each method’s capability and its risk in estimation spatial distribution of heavy metals in soil, 437 samples of Chang-Hwa were selected. The results indicate that RBF Method has the most accuracy in this experiment. Kriging and Fuzzy estimation are in the second place. IDW is third. While, both GPI and LPI are not suitable for application to estimate of spatial distribution of heavy metals in soil.

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Zhuang, Kai Wei, and 莊愷瑋. "Prediction of spatial distribution of heavy metals in contaminated soils by geostatistics." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/09990711972666265318.

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碩士 國立臺灣大學 農業化學研究所 83 The objectives of this study are using geostatistics and traditional statistical methods to predict the spatial dis- tribution of heavy metal in contaminated soils and to search for the most efficient sampling strategy for contaminated site characterization.Two study sites located at Tou-Yuan County were selected. The spatial distribution of soil Cd, Pb and Zn concentrations were predicted by kriging in this study. The results showed that the spatial distribution of those heavy metal concentrations estimated by ordinary kriging varied with the sampling numbers used. However, the accuracy of prediction is mainly dependent on whether the outlier data are sampled. There is no significant difference between the estimated values using spherical and exponential semivariogram model. But the estimated values using gaussian model were higher than those using spherical and exponential models at the location having high concentrations of heavy metal. The natural logtransformation of data of this study resulted in largees timated biasedness. The topsoil Cd and Pb concentrations insite A predicted by indicator kriging were more accurate than those predicted by natural log-transformed ordinary kriging. The accuracy of topsoil Cd and Pb concentrations'' prediction can be improved by the assistance of other available Cd, Pb,and Zn concentrations of topsoils or subsoils using Q-mode factor approximation. The relationship between the probability of obtaining outliers and relative sampling cost is developed and proposed as a guideline for searching the most efficient sampling strategy for characterization of spatial distribution of pollutants in contaminated soils.

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Wang, Yun-Yih, and 王允義. "Identification of Spatial Distribution of Heavy Metals in Cont aminated Soils by Geostatistical Method." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/89440989574728857628.

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碩士 國立臺灣大學 農業工程學系 84 The purpose of this research is trying to find out the soil contaminated sites in Taiwan. First, the surveyed data of 1600 ha-grid and the tentative threshold of the monitoring and control values which EPA suggests are compared. Second, the Kriging me- thod of geostaistics is used to find out the best semivariogram and concentration contour in each county. Finally, the contami- nated sites are identified. The results shows that up to 13 counties among the 15 coun- ties have the value exceeding the monitoring threshold and need to be identified. Various semivariogram models are used in this research to fitted Experimental semivariogram. Spherical model analysis is used on the evaluation of Taipei and Nanto counties. The Gaussian model is adapted to analysis the other 11 counties. Upon using the nature-log transformation, only the value of Taipei county show the obvious progress in the semivariogram analysis. Furthermore, the Zn contaminated in the soil of Chang- hwa county is measured to find out if different methods will have influence on the estimated value. The conclusion is the estimated value gained from Spherical model and Gaussian model is closer. However, the estimated value gained from Spherical model is less similar to the value from Gaussian model. The identification result is made into the graph and enclosed in Appendix as reference.

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