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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Characterizing Current and Geologic Phosphorus in Utah Lake Sediment Using Field Samples, Laboratory Methods, and Statistical Analysis: Implications for Water Quality Issues

Abu Hmeidan, Hani Yousef 01 March 2017 (has links)
Phosphorus is an essential nutrient for aquatic life forms and plays a major role in the algae blooms that occur in lakes and reservoirs. It is considered a primary limiting nutrient of phytoplankton growth in streams, lakes, and reservoirs. Excess amounts of phosphorous may cause excess growth and biomass of algae. If phosphorus is available in excess, often from sewage and industrial discharges, the high levels in a lake or reservoir can lead to eutrophication. Utah Lake is a shallow, basin-bottom lake in a semi-arid climate with sediments that are thousands of feet thick. Starting 165 years ago, humans have been discharging wastewater into Utah Lake, which in our day has raised serious questions on how the state can mitigate the negative effects of the external nutrient loading. Even though Utah Lake receives a significant amount of anthropogenic phosphorous, there are high levels of phosphorous in geologic deposits in the area, providing a long-term natural source. This study intends to provide data on the current distribution of phosphorous in lake sediments, potential for that phosphorous to be released into the water column affecting phytoplankton growth, and how historic lake sediment phosphorous levels compare to the levels in current sediments. Sediments play an important role in the overall metabolism of shallow lakes. They supply the water column with phosphorus and must be considered as they serve as a sink and source. More than 50 branches of surface flow discharge into Utah Lake, 15 of which are major. Based on previous data, a positive retention of phosphorus from these branches occurs in the lake, of which the sediment plays a role. Phosphorus release from sediment occurs under very complicated processes under many different conditions. Some main influential factors include the iron and calcium content, redox potential, microbial processes, turbidity, sediment resuspension, temperature, and pH. In this study, I analyzed 85 sediment samples sampled across Utah Lake for total phosphorus. I created Geospatial maps to show the phosphorous distribution. The data showed an average phosphorus level of 666 ppm and varied in distribution throughout the lake, though the majority of the lake had levels in the 600 to 800 ppm range. There were a few samples, which had lower total phosphorus levels, in the 200 to 300 ppm range. Based on the map, I found that these lower values were in locations representing potential springs. I hypothesize that this underground water source leached some of the phosphorous from the sediments in these areas. I found that total phosphorus concentrations in current lake sediment are quite similar to phosphorus levels in historic lake sediments levels. I also performed laboratory experiments to characterize sediment-water interactions and estimate the amount of phosphorus that could be released from lake sediments to the water column.
2

Monitoring and Modeling Total Phosphorus Contributions to a Freshwater Lake with Cage-Aquaculture

Milne, Jacquiline 24 August 2012 (has links)
A mass-balance modeling approach has been applied to gain an improved understanding of the relative contributions of phosphorus loading from various sources into a freshwater lake with cage-aquaculture in Ontario. All cage-aquaculture in Ontario is located within Lake Huron and Georgian Bay of the Great Lakes where concerns about potential environmental issues are constraining growth of the industry. Phosphorus is of particular concern for cage-aquaculture operations in Ontario since this nutrient may accelerate eutrophication of freshwater. Sound scientific information is needed for the Ministry of Environment lake managers to make defensible decisions to move the industry forward in a sustainable manner. Lake Wolsey is located on Manitoulin Island in Lake Huron, Ontario. The lake is connected to the North Channel by a small inlet where water exchanges periodically. A cage-aquaculture operation was established in 1986 and has an average annual production of approximately 250 metric tonnes of rainbow trout. We have estimated total phosphorus loadings from eight sources of inputs and three sinks from the lake. We then applied a sensitivity analysis to establish parameters that require empirical measurement and field validation. Results show non-point sources as the leading contributor of total phosphorus to Lake Wolsey (40%, 1120 kg) followed by the farm (32%, 915 kg), groundwater (11%, 305 kg), and dwellings (8%, 219 kg), internal phosphorus load from the hypoxic hypolimnion mid-lake (7%, 186 kg), precipitation (3%, 79 kg) and leaf litter (0.3%, 8 kg). Results of the sensitivity analysis show non point sources to be the most significant parameter in terms of total phosphorus loading, followed by the lake sedimentation, then the contribution by the aquaculture operation. This is followed by the exchange via the inlet, groundwater, dwellings, the internal phosphorus, sportfishing, precipitation and leaf litter. Information from this project will provide water quality managers with scientific information to aid in decisions pertaining to policy and regulatory approaches for water quality risk assessment and management of cage-aquaculture in Ontario. / Great Lakes Sustainablility Fund, Great Lakes Action Plan V, Ontario Sustainable Aquaculture Working Group
3

Future Strategy for Wastewater Treatment at Skärblacka Mill

Brusved Andersson, Linnea January 2014 (has links)
To replace nonrenewable materials, glass, plastics and metals, at the market the production of the environmental friendly material paper needs to increase numerously. An increased paper production leads to an enlarged wastewater flow at the paper mill and thereby higher surface load in the biologicalwastewater plant. Higher surface load in turn, leads to lower efficiency and higher emissions. To be able to increase the capacity of the paper production, the wastewater flow to the biological wastewater treatment needs to be decreased. In this thesis, the wastewater at Skärblacka mill has been studied to identify how to increase the production without increasing the flow of wastewater to the biological wastewater treatment. Different wastewater has been studied to identify sufficient clean wastewater flows that today are directed to the biological wastewater treatment. The outcome of this thesis is that up to 600 m3/h wastewater could be removed from the biological wastewater treatment due to sufficiently high purity. This outcome is primarily based on measurements of the emission parameters, Total Organic Carbon, Suspended Solids, Total Phosphorus and Total Nitrogen and the calculation of PEC/PNEC, environmental assessment, for the chemicals in the wastewater. The unload of up to 600 m3/h will contribute to an increased efficiency in the biological wastewater treatment and thereby lower emissions. Increased efficiency and lower levels of emissions will in turn contribute to a possibility to increase the paper production at Skärblacka mill without interfering withenvironmental demands.
4

Turbiditet som ersättningsmått för totalfosforhalt i kustmynnande vattendrag i Östergötland / Turbidity as a surrogate measure for total phosphorus concentrations in coastal streams in Östergötland

Åberg, Elin January 2014 (has links)
Eutrophication is a major problem in the Baltic Sea, as a result of increased loading of nitrogen and phosphorus. In the coastal parts of Östergötland the soil largely consists of clay and contains high levels of phosphorus bound to clay particles. Erosion of the soil in agricultural areas makes the water turbid and transports phosphorus to the Baltic Sea. The aim of this project was to examine the relationship between phosphorus and turbidity in the coastal streams of Östergötland. The aim was also to evaluate the possibility to use turbidity as a surrogate measure for phosphorus. Water samples from 41 streams along the coast of Östergötland were collected once from each location 7 – 11 of April 2014. Variables examined were turbidity, total phosphorus, molybdate reactive phosphorus and water color (absorbance 420 nm). On average, particulate phosphorus made up 80 % of total phosphorus. The study showed a significant correlation between total phosphorus and turbidity (R2adj=0.879, P<0.01, linear regression). Water color was not correlated with total phosphorus. A multiple regression with turbidity and water color as independent variables resulted in a slightly improved model (R2adj = 0,886), but was regarded as not meaningful considering the additional efforts. The conclusion of the project is that is it possible to use turbidity as a surrogate measure in these streams. / Övergödning av Östersjön är ett stort problem orsakat av ett överskott av kväve och fosfor. I de östra delarna av Östergötland består jordarna till stor del av lera och innehåller rikligt med fosfor bundet till lerpartiklarna. Vid erosion från jordarna grumlas kustmynnande vattendrag och fosfor transporteras ut till Östersjön. Syftet med projektet var att undersöka om mätning av turbiditet kan användas för att uppskatta koncentrationen av totalfosfor i Östergötlands kustmynnande vattendrag. En fältstudie genomfördes där 41 vattendrag provtogs en gång per lokal den 7 - 11 april 2014. Vattenprover från lokalerna analyserades med avseende på totalfosfor, molybdatreaktiv fosfor, turbiditet och färg (absorbans 420 nm). I genomsnitt så bestod 80 % av totalfosfor av partikulärt bunden fosfor. Det fanns ett signifikant samband mellan totalfosfor och turbiditet (R2 adj =0,879, P<0,01, linjär regression) men inte mellan färg och totalfosfor. Vid multipel regression med turbiditet och färg som oberoende variabler förbättras förklaringsgraden så marginellt (R2adj=0,886) att det inte motiverar analys av färg, då det ger en ökad arbetsinsats. Projektet visar att turbiditet går att använda som ersättningsmått för totalfosforhalt i kustmynnande vattendrag i Östergötland.
5

Totalfosforhalten i Bällstaån / Total phosphorus contents in Bällstaån

Lundqvist, Andreas January 2019 (has links)
De höga halterna av totalfosfor i Bällstaån strider mot de mål och normer som är uppsatta av regeringen. Senast 2027 måste Bällstaåns totalfosforhalt minska kraftigt, från nuvarande otillfredsställande nivå (91 μg/L) till minimumnivån god ekologisk status (40 μg/L). Samtidigt ligger Bällstaån i ett expansivt område i Stockholms län vilket gör framtiden oviss. Syftet med projektet är att försöka undersöka vilka fosforkällor som påverkar Bällstaån och hur fosforn transporteras från källa till ån. Sammanställning av mätdata avseende totalfosfor har gjorts för provpunkter längs Bällstaån, för en serie med mätperioder, för att kunna bestämma vilka provpunkters totalfosforhalt som skiljer sig från omgivande provpunkter. Med hjälp av Excel har grafer framställts från mätvärdena för att kunna ge en tydlig bild. Endast provperioder med månatliga mätningar har använts och bara provpunkter med minst 3 sammanhängande provperioder, för att minimera felkällor. Provperiod för 2013 har använts som utgångspunkt, då det är den senaste provperioden med månatlig provtagning. Totalt har mätåren 2013, 2009 och 2004 används för alla punkter och för vissa punkter även 1999 och 1992. För att skapa ytterligare giltiga punkter skarvades närliggande provpunkter samman om en giltig provperiod kunde skapas. Detta gjordes eftersom antalet punkter varierat mellan provperioderna och vissa punkter ersatts. En litteraturstudie och granskning av markanvändningen i området har använts för att kunna förutse hur fosforn når ån och försöka förklara var fosforn kommer ifrån. Med hjälp av höjddata från Lantmäteriet togs kartor fram i ArcMap, främst med verktyget ArcHydro Tools. Dessa kartor visar avrinningsområden, delavrinningsområden och olika provpunkter. Resultatet av litteraturstudien visade att möjliga fosforkällor till Bällstaån med betydande miljöpåverkan är jordbruk, dagvatten och industrier. Markanvändningen inom avrinningsområdet klargjorde att majoriteten av ytan består av hårdbelagda ytor i en urban miljö. Hårdgjorda ytor är de ytor där det inte sker någon infiltration av vatten ner i marken och en urban miljö är en stadsmässig miljö. Sammanställningen av mätdata visade att för de tre provperioder 2004, 2009, 2013 så gavs 9 giltiga provpunkter, plus en sammanslagen punkt, den mellan Ankarstocksbron och Travbron. Av dessa 10 punkter visade Veddesta dike och Brädgårn höga halter totalfosfor i förhållande till omgivande punkter. Slutsats kring utsläppspunkterna var att dagvattenutloppen stod för den största fosfortillförseln. Troliga fosforkällor för Veddesta dike var trafikerade vägar i området, Veddesta industriområde och de hårdgjorda ytor där dagvattnet leds ut i Veddesta dike. För Brädgårn var troliga fosforkällor trafikerade vägar i området, Bromstens industriområde och de hårdgjorda ytor där dagvattnet leds ut i Brädgårn. / The high levels of phosphorus in the river Bällstaån are in contradiction to the environmental goals and norms set by the Swedish government. By 2027 the total phosphorus content in Bällstaån's has to decrease sharply, from the current “unsatisfactory” level (91 µg/L) to the minimum level “good” ecological status (40 µg/L). Simultaneously, Bällstaån is located in an expansive area in Stockholm making the future uncertain. The purpose of the project is trying to investigate which phosphorus sources affect Bällstaån and how the phosphorus is transported from source to river. A compilation of measurement data regarding total phosphorus has been made of sampling points along Bällstaån, for a series of measurement periods, in order to determine which sampling points phosphorus levels that differ from the surrounding sampling points. Graphs have been produced in Excel to visualize the measurement values. Only test periods with monthly measurements are used and only sample points with at least 3 consecutive sample periods are used, to reduce error sources. The 2013 sample period is used as a starting point, as it is the newest period with monthly samplings. The sample periods used are 2013, 2009 and 2004 for all sample points. For some sample points the additional sample periods, 1999 and 1992, were added. To create additional sample points two adjacent sample points are co-joined so a valid trial period can be created. This is due to the fact that a number of sample points varied between the sample periods and some points have been replaced. A literature study and review of land use in the area has been conducted to predict how the phosphorus reaches the river and where it comes from. Using elevation data from Swedish National Land Survey, I have been produced maps in ArcMap, primarily with the tool ArcHydro Tools. These maps show basins, sub-basins and sample points. The result of the literature study shows that possible phosphorus sources to Bällstaån with significant environmental impact are agriculture, stormwater and industries. The land use in the basin area showed that the majority of the surface consists of large zones of hard-coated surfaces. The compilation of measurement data shows that for the three sample periods 2004, 2009 and 2013 9 valid test points were selected with the addition of a merged point, the one between the Ankarstocksbron and Travbron. Of the 10 test points, Veddesta dike and Brädgårn revealed high levels of total phosphorus. The conclusion regarding emission points was that stormwater outlets accounted for the largest amount of phosphorus. Probable sources of phosphorus for Veddesta dike were found to be the roads with heavy traffic, Veddesta industrial area and the area in which stormwater network is covering hard-coated surfaces within Veddesta dike sub-basin. For Brädgårn, the probable phosphorus sources were the roads with heavy traffic, Bromsten industrial area and the hard-coated surfaces within the sub-basin covered by the stormwater network.
6

Data-driven analysis of water and nutrient flows: Case of the Sava River Catchment and comparison with other regions

Levi, Lea January 2017 (has links)
A growing human population and demands for food, freshwater and energy are causing extensive changes in the water and biogeochemical cycles of river catchments around the world. Addressing and investigating such changes is particularly important for transboundary river catchments, where they impose additional risk to a region’s stability. This thesis investigates and develops data-driven methodologies for detecting hydro-climatic and nutrient load changes and their drivers with limited available data and on different catchment scales. As a specific case study, we analyze the Sava River Catchment (SRC) and compare its results with other world regions. A past–present to future evaluation of hydro-climatic data is done on the basis of a water balance approach including analysis of historic developments of land use and hydropower development data and projections of the Coupled Model Intercomparison Project, Phase 5 (CMIP5) output. Using observed water discharge and nutrient concentration data, we propose a novel conceptual model for estimating and spatially resolving total nitrogen (TN) and total phosphorus (TP) input and delivery-retention properties for a river catchment and its nested subcatchments, as well as detection of nutrient hotspots. The thesis identifies hydroclimatic change signals of hydropower-related drivers and finds consistency with other world regions. The proposed nutrient screening methodology provides a good distinction between human-related nutrient inputs and landscape-related transport influences on nutrient loading at subcatchment to catchment scale. A cross-regional comparison of the SRC data with the Baltic region shows similarity between nutrient-relevant indicators and driving socio-economic and hydro-climatic conditions. The study highlights a number of complexities with regard to CMIP5 model representation of water fluxes. The large intermodel range of CMIP5 future projections of fluxes calls for caution when using individual model results for assessing ongoing and future water and nutrient changes. / <p>QC 20170516</p> / VR 2009-3221 / FORMAS 2014-43
7

Spatial and Temporal Distribution of Total Phosphorus Concentration in Soil and Surface Water in the Everglades Protection Area

Sarker, Shishir Kumar 26 June 2018 (has links)
Draining of the Everglades allowed for the expansion of urban and agricultural development, reducing half of the size of the historic Everglades. The detrimental cascading effect on the Everglades ecosystem function is related to the total phosphorus (TP) concentrations of water inflow, the inflow rate and the distance from the discharge point. As Everglades restoration has approached 15 years since the inception of the Comprehensive Everglades Restoration Plan (CERP), there is a need to assess its progress across the ecosystem. Available data from 2004 to 2014 were collected for soils and from 2004 to 2016 for water to understand a decade of trends. Both Geographic Information System (GIS) and statistical data analysis were applied to determine changes in water quality and soil chemistry. Key findings indicate a declining trend in water TP, with mixed results for soil. Higher TP concentrations (>10 µg/L) were prevalent the areas less than 1 km from a canal or water discharge point for both soil and water. The TP in surface water was higher in the wet season compared to the dry season across the EPA possibly associated with hydrologic, climatic or other factors.
8

The Study of Treating Leachate in Landfill by Constructed Wetlands

Tsai, Kai-yuan 04 September 2004 (has links)
In this research, we dealt with the original landfill leachate, and put the flowing water by a traditional second one that has dealt with of sewage factory directly with the constructed wetland systems in lab-scale. The purpose the study is to compare the experimental results after dealing the leachate by different constructed wetland process systems which was judge at if the, can reach the water quality standard. The constructed wetland systems in the study were set up in a greenhouse on campus, which were operated between May 2004 and July 2003. Constructed wetland systematic attitude, include Free Water Surface System (FWS) and Subsurface Flow System (SSF) contact but two type constructed wetland system that become mainly. In the test use different waste water sources to feet the systems, and we planted different species of plants, and add extra carbon source. Thus, we can divide the experiment into two stages: (1) From July of 2003 to December of 2003. (2) From February of 2004 to May of 2004. In each stage, we tested three experiment group P1, P2 and total nitrogen of P3 except that the rate is 37¡Ó20%, 50¡Ó11% respectively and -6.1¡Ó37.8%. The removal efficiencies of ammonia nitrogen were estimated equal to 84¡Ó11%, 94¡Ó4% and 60¡Ó24% respectively. For total phosphorus and phosphate, P1 , P2 and P3 system were measured equal to 37¡Ó14%, 68¡Ó16% and 77¡Ó16%and 44¡Ó16%, 75¡Ó8% and 80¡Ó17% respectively . The ammonia nitrogen temperature correction coefficient (£c value) were calculated to be 0.921, 0.949, 0.926, 1.043 and 0.785 for P1, P2, P3, U1 and U2 system, respectively. The phosphate temperature correction coefficients (£c values ) were measured to be 1.006, 0.981, 1.070, 1.235 and 0.843 respectively for P1, P2, P3, U1 and U2 system. In order to increase the removal efficiencies of total nitrogen, it was always by adding carbon source. The experimental result showed, that it is add carbon source wait by system to SSF , its President nitrogen is it flow water pollution load leave 2g/m2/day nearly to put to have, and has not added water pollution load has flowed in the putting of the carbon source nearly has 6g/m2/day left, And nearly remain under 1g/m2/day in the putting and flowing water pollution load of TON, and not added the putting of the carbon source water pollution load has flowed nearly has 2-3g/m2/day left. This result showed that high total nitrogen removal efficiencies were by adding carbon source.
9

Kėdainių ir Rokiškio miestų nuotekų valyklų efektyvumo tyrimai / Efficiency Evaluation of Wastewater Treatment Plants in Kėdainiai and Rokiškis Towns

Butkus, Paulius 30 May 2012 (has links)
Tyrimo objektas – Kėdainių ir Rokiškio miesto nuotekų valyklos. Tyrimo tikslas – nustatyti, įvertinti ir palyginti Kėdainių ir Rokiškio miestų nuotekų valyklų veikimo efektyvumą prieš ir po rekonstrukcijos. Darbo uždaviniai: 1. Surinkus esamus tyrimų duomenis nustatyti, įvertinti ir palyginti Kėdainių ir Rokiškio miestų nuotekų valyklų efektyvumą prieš ir po rekonstrukcijos; 2. Atlikti surinktų duomenų statistinę analizę; 3. Nustatyti priklausomybes tarp teršiančių medžiagų koncentracijų atitekančiose ir ištekančiose nuotekose; 4. Nustatyti teršiančių medžiagų koncentracijų po nuotekų valymo priklausomybes nuo temperatūros; 5. Nustatyti Pb ir Nb koncentracijų priklausomybes ištekančiose nuotekose nuo BDS7/Pb ir BDS7/Nb santykio atitekančiose nuotekose. Tyrimo metodai: Kėdainių ir Rokiškio miestų nuotekų valyklos efektyvumui nustatyti buvo atliekama nuotekų užterštumo analizė atsižvelgiant į biocheminio (BDS7) ir cheminio deguonies (ChDS), skendinčių medžiagų (SM), bendro azoto (Nb) ir bendro fosforo (Pb) koncentracijas prieš užterštų nuotekų valymą ir po valymo. UAB „Kėdainių vandenys“ ir UAB „Rokiškio vandenys” laboratorijose surinkti 2008–2011 metų tyrimų duomenys apdoroti naudojant Microsoft Excel 2007 ir STATISTICA programas. Tyrimo rezultatai: Pirmajame skyriuje aprašomas nuotekų tvarkymas Lietuvoje, nuotekų tvarkymo būdai ir jų efektyvumas, pagrindinės nuotekų užterštumo charakteristikos, reikalavimai išleidžiamoms nuotekoms ir nuotekų valymo metu susidariusio dumblo... [toliau žr. visą tekstą] / Object of the research: wastewater treatment plants in Kėdainiai and Rokiškis towns. Aim of the research work: to determine, evaluate and compare the efficiency of the wastewater treatment plants in Kėdainiai and Rokiškis towns before and after their reconstruction. Objectives: 1. Following the research data, to determine, evaluate and compare the efficiency of the wastewater treatment plants in Kėdainiai and Rokiškis towns before and after their reconstruction; (Why do you repeat the aim??) 2. To carry out the statistical analysis of the obtained research data; 3. To determine the proportion of pollutant concentrations in the incoming wastewater and in the effluent; 4. To determine how the pollutant concentrations that are found after the wastewater treatment are affected by temperature; 5. To determine how the Pt and Nt concentrations in the effluent depend on the proportion of BOD7/Pt and BOD7/Nt in the incoming wastewater. The research methods: to determine the efficiency of the wastewater treatment plants in Kėdainiai and Rokiškis towns, the analysis of the wastewater contaminants was performed considering the following data: concentrations of biochemical (BOD7) and chemical oxygen (COD), suspended solids (SS), total nitrogen (Nt) and total phosphorus (Pt) that were fixed before and after the contaminated wastewater treatment. The data of the research, which was carried out and stored in the laboratories of UAB Kėdainių vandenys and UAB Rokiškio vandenys in... [to full text]
10

Using satellite hyperspectral imagery to map soil organic matter, total nitrogen and total phosphorus

Zheng, Baojuan. January 2008 (has links)
Thesis (M.S.)--Indiana University, 2008. / Title from screen (viewed on June 3, 2009). Department of Earth Science, Indiana University-Purdue University Indianapolis (IUPUI). Advisor(s): Lin Li, Pierre Jacinthe, Gabriel M. Filippelli. Includes vita. Includes bibliographical references (leaves 78-81).

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