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Surface Water and Groundwater Hydrology of Borrow-Pit Wetlands and Surrounding Areas of the Lewisville Lake Environmental Learning Area, Lewisville, TexasDodd-Williams, Lynde L. 08 1900 (has links)
The focus of this study was to characterize the surface water and groundwater hydrology of borrow-pit wetlands located within the borders of the Lewisville Lake Environmental Learning Area (LLELA), east of the Elm Fork of the Trinity River. The wetlands were excavated into alluvial deposits downstream of the Lewisville Lake Dam. Both surface water and groundwater contribute to the hydro-period of the borrow-pit wetlands. Nearby marshes exhibit characteristics of groundwater discharge. Salinity in groundwater-fed wetlands could affect establishment of vegetation, as suggested from plant surveys. Surface water input from storm events dilutes salinity levels. Management of LLELA wetlands should include long-term evaluation of hydrology and plantings to enhance habitat. Plans for additional wetlands should consider both surface water and groundwater inputs.
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ENABLING LARGE-SCALE HYDROLOGIC AND HYDRAULIC MODELING THROUGH IMPROVED TOPOGRAPHIC REPRESENTATIONSayan Dey (7444328) 19 December 2021 (has links)
<p>Topography is one of the primary drivers of
physical processes in the rivers and floodplains. Advances in remote-sensing
and survey techniques have provided high-resolution representation of the
floodplains but information regarding the 3D representation of river channels
(commonly known as river bathymetry) is sparsely available. Field surveys along
an entire river network in a watershed remains infeasible and algorithms for
estimating simple but effective characterization of river channel geometry are
hindered by an incomplete understanding of the role of river bathymetry in
surface and subsurface processes. </p>
<p> The
first objective of this dissertation develops an automated framework – System
for Producing RIver Network Geometry (SPRING) for improving the geospatial
descriptors of a river network. The tool takes as input the DEM and erroneous
river centerline to produce spatially consistent river centerlines, banks, and
an improved representation of river channel geometry. SPRING can process entire
river networks and is not limited single reach applications. The proposed
framework is flexible in terms of data requirements, resolution of output
datasets and user preferences. It has a user-friendly graphic user interface
(GUI) and is appropriate for large-scale applications since it requires minimal
user input.</p>
<p> A
better understanding of the role of bathymetric characteristics in surface-subsurface hydrology and hydrodynamics can
facilitate an efficient incorporation of river bathymetry in large river
networks. The second objective explores the level of bathymetric detail
required for accurately simulating surface and subsurface processes by developing
four bathymetric representations using SPRING with reducing level of detail.
These bathymetric configurations are simulated using a physically based tightly
coupled hydrologic and hydrodynamic model to estimate surface and subsurface
fluxes in the floodplains. Comparison of fluxes for the four bathymetric
configurations show that the impact of river bathymetry extends beyond surface
routing to surface water – groundwater interactions. Channel conveyance
capacity and thalweg elevation are the most important characteristics
controlling these interactions followed by channel side slope and channel
asymmetry. </p>
<p> The
final objective aims to develop benchmarks for bathymetric characteristics for
accurately simulating flooding related physical processes. The sensitivity of
surface and subsurface fluxes to error in channel conveyance capacity is
investigated across reaches with varying geomorphological characteristics. SPRING
is used to create six bathymetric configurations with varying range of error in
channel conveyance capacity (ranging from 25% to 300%). They are simulated
using a tightly coupled physically distributed model for a flood event and the
estimates of water surface elevation, infiltration and lateral seepage are compared.
Results show that incorporating channel conveyance capacity with an error of
within 25% significantly improves the estimates of surface and subsurface
fluxes as compared to those not having any bathymetric correction. For certain
reaches, such as those with high drainage area (>1000km<sup>2</sup>) or low
sinuosity (< 1.25), errors of up to 100% in channel conveyance capacity can still
improve H&H modeling.</p>
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Studie úpravny vody z povrchového zdroje / Study of water treatment plant from surface sourceInwald, Petr January 2021 (has links)
The first part of the thesis deals with water sources and methods of drinkable water treatment. This section describes the technologies used for two-stage water treatment from a surface source. The second part deals with study of the new drinking water treatment plant from a surface source for Adamov town. The work documents the current state of the existing water treatment plant and describes used technology with a design flow Q = 30 l s-1. In the next part of thesis is design of two variations of new technological line with a design flow Q = 10 l s-1. The first variation is one-stage water treatment with pressure filters as the main separation stage. Two-stage water treatment is designed for the second variation, in which the first stage of separation are clarifiers and the second stage are pressure filters. Thesis includes drawing documentation of designed pressure filters and clarifiers, technological and height scheme of both variations.
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Problematika perfluorovaných sloučenin ve složkách životního prostředí / Issues of perfluorinated compounds in the environmental compartmentsKalášek, Stanislav January 2008 (has links)
Perfluoroalkylated substencies are priority organics polutants. They are evolved to the environment from many sources. We classify them as new xenobiotics which are present in the environment. There will be described their chemical, physical and environmental properties in theoretical part and there will be described the analytical chemistry of these substancies in varios types of environmental samples. There will be developed metod for their identification and quantification. For this assignment will be use especially chromathografic methods. There will be developed standard operation procedure. The procedure will be verify on real environmental samples.
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Využití plynové chromatografie pro stanovení reziduí léčiv ve vodách / Aplication of gas chromatography for determination of drug residuals in watersLacina, Petr January 2009 (has links)
Diploma thesis is focused on the choose of methods and optimalisation analysis procedure of selected pharmaceuticals (salicylic acid, ibuprofene, naproxene, ketoprofene and diclofenac) in surface and waste water by using gas chromatography with mass spectrometer (GC-MS). Solid-phase extraction (SPE) with Oasis HLB cartridges was used as an extraction method in this analysis. Extraction is followed by derivatization and their optimalization of selected pharmaceuticals. Derivatization and its optimalization were performed by two silylation reagens N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA) and N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA). Different volumes of derivatization reagents, different temperatures and different times were used during the procedure. The best combination is then used for analysis of real samples. Real samples of waste water were collected in sewage treatment plants in Brno – Modřice and real samples of surface water were collected from several rivers and one pond in region Moravia. This thesis also presents and tests SPE methods for extraction and concentration selected sulfonamide residues (sulfamethazine, sulfamethoxazole, sulfapyridine and sulfathiazole) from the aquatic environment.
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Upravitelnost povrchových vod / Treatibility of surface waterFuks, Josef January 2013 (has links)
The aim of the master´s thesis is the topic of the treatability of surface water with the focus on the process of suspension formation. For this work I took water samples from five different places around the Brno Dam which has contended with water quality deterioration for a long period. With these water samples, the series of jar coagulation tests were done with the application of three different commonly used coagulants. In the theoretical part of the master´s thesis I deal with the composition and attributes of surface water and the technology of its treatment. Each process of treatment is briefly described here with the emphasis on the process of suspension formation. The experimental part of the master´s thesis summarizes and presents the results gained through the coagulation tests in the laboratory. I evaluate the influence of different parameters on final effectiveness of water treatment and I try to find an optimal amount of coagulant, pH and speed of fast or slow mixing. Finally I compare the suitability of each coagulant and the influence of the sampling site on the effectiveness of water treatment.
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Nekonvenční technologie obrábění vodním paprskem / The unconventional Technology of Cutting Water JetŠimíček, Václav January 2010 (has links)
This diploma thesis deals with the unconventional technology of cutting water jet. The aim of this thesis is analysis of technological possibilities of water jet, possible operating modes (techniques) and entering technological data and influence of technical parameters on quality and accuracy of cutting. The thesis contains several experiment at which was examined achieved quality and accuracy of cuts, and simultaneously there is solved technoeconomic evaluation of this technology.
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Studium degradace léčiv s využitím pokročilých oxidačních procesů / Study of Pharmaceuticals Degradationby Advanced Oxidation ProcessesBílková, Zuzana January 2015 (has links)
At present, the issue of occurrence of female sex hormones, estrogens and progestogens, in aquatic ecosystems is often discussed by experts and the general public. These substances of steroid structure can be difficult to remove completely by conventional wastewater and drinking water treatment technologies. In given context advanced oxidation processes based on in situ generation of highly reactive hydroxyl radicals can be a suitable technique. This thesis deals with the study of kinetics and degradation products of photocatalytic decomposition of seven female sex hormones (estrone, -estradiol, estriol, ethinylestradiol, diethylstilbestrol, progesterone and norethindrone). Experiments were conducted in a laboratory glass reactor, which was equipped with an energy efficient UV-A LED light source (365 nm emission wavelength) and an immobilised photocatalyst in a form of TiO2 five-layer film deposited on glass. Model samples of water with the initial hormone concentration of 1 mg·L-1 were used and the degradation process was monitored by an HPLC-MS method. In the given system all compounds of interest except estriol had very significant tendency to be adsorb. In the case of estriol the formal rate constant of photocatalytic decomposition was determined based on the Langmuir-Hinshelwood model for two different initial concentrations, 0.5527 hour-1 (1 mg·L-1) and 0.1929 hour-1 (5 mg·L-1), and by comparison of these values it was found that the higher degraded compound concentration, the slower decomposition (fivefold increase of the initial concentration resulted in the constant decrease to almost one-third). Moreover nine degradation products of estriol photocatalytic decomposition were recorded and their structure was designed based on mass spectra. In the second thematic part of the thesis attention was paid to development of a SPE-HPLC-MS method for simultaneous determination of female sex hormones in water ecosystems, with emphasis on an extraction part optimization. The final samples treatment process included besides extraction with Supel™ Select HLB 200 mg SPE cartridges also mechanical impurities removal, hormones extraction from solids trapped on filtration material, sample acidification and extract purification with Supelclean™ ENVI-Florisil® cartridges. Optimised method was used for determination of female sex hormones in two Brno rivers, Svitava and Svratka. In the most cases the concentration was below the detection or quantification limit.
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The suitability of estrogen and androgen bioassays for the measurement of endocrine activity in different water matricesNgcobo, Silindile January 2017 (has links)
Endocrine disrupting chemicals (EDCs) are ubiquitous in the environment and their
presence in water bodies is documented. They discharge into surface water (SW)
unmonitored, posing a threat to both aquatic and terrestrial lives. This is a challenge
as not all populations have access to treated drinking water (TDW). The EDC
contaminated serves as a route of exposure, together with ineffective treatment
plants. Given the complexity of the endocrine system, EDCs may mimic or
antagonise natural hormones or disrupt their synthesis, metabolism and excretion.
The associated health effects include testicular dysgenesis syndrome, metabolic
disorders and cancers. Policy and internationally standardised test methods are
however sti ll limited. This study therefore aimed to assess the suitability of two
assays used for screening estrogenic activity and one for androgenic activity in
different water sources.
The study consisted of two phases. In phase 1, water sample (tap, surface and
treated wastewater) were collected from a catchment area in Pretoria. The samples
and a spiked MilliQ laboratory water sample were extracted with solid phase
extraction (SPE) and sent to Germany for distribution to participating laboratories.
Samples (n=24) from six different countries were received to test for androgenic
activity in the MDA-kb2 reporter gene assay. In phase 2, SW and TDW samples
were collected from April 2015 until March 2016. The samples were filtered,
extracted using SPE and assayed with the YES assay, T47D-KBluc reporter gene
assay for estrogenic activity and MDA-kb2 reporter gene assay for androgenic
activity. In phase 1, androgenic activity was detected in 4 out of 24 (21%) samples and
ranged from 0.23 ± 0.040 ng/L to 0.008 ± 0.001 ng/L DHTEqs. In phase 2,
estrogenic activity was detected in 16 out of 24 (67%) SW samples in the T47DKBluc
reporter gene assay and ranged from 0.31 ± 0.05 pg/L to 10.51 ± 5.74 pg/L
EEqs. It was below the detection limit (dl) in the YES assay. Androgenic activity was
detected in 4 out of 24 (17%) SW samples, ranging from 0.0033 ± 0.0050 ng/L to
0.090 ± 0.040 ng/L DHTEqs. Androgenic and estrogenic activity was higher i n pretreatment
samples compared to post-treatment in both treatment plants. In phase 1, the MDA-kb2 reporter gene assay was successfully applied to water
samples from different sources. Androgenic activity was highest in treated
wastewater. In phase 2, treatment plants proved to be effective in removing
estrogens detected in the SW samples, as the TDW samples were below the dl.
Estrogenic activity is within the ranges reported in other studies. Positive samples
were below the 0.7 ng/L proposed trigger value for health risk assessments.
Detected androgenic activity was lower in TDW samples compared to the SW
samples supplying the two treatment plants indicating that they were both effective in
removing the androgenic activity detected. Few studies have reported androgenic
activity in tap water. This study strengthens the argument for using a battery of assays when monitoring
endocrine activity as EDCs occur at low concentrations in mixtures. / Dissertation (MSc)--University of Pretoria, 2017. / School of Health Systems and Public Health (SHSPH) / MSc / Unrestricted
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Determination of anions and cations in natural waterNetshifhefhe, Humbelani Kelly 21 September 2018 (has links)
MSc (Chemistry) / Department of Chemistry / Surface water is used for domestic and agricultural activities in Musina region and other surrounding areas. This is because of the shortage of potable water. As a result, the people living in the region and its surrounding areas are potentially exposed to hazardous contaminants that may be present in the surface water. It is therefore important to ascertain the quality of the surface water in the region.
Surface water samples were collected from Mutale, Nwanedi, Tshipise and Nzhelele rivers. The samples were analysed for anions such as fluoride (F-), chloride (Cl-), nitrate (NO3-), phosphate (PO43-), sulphate (SO42-); cations such as aluminium (Al), calcium (Ca), iron (Fe), potassium (K), magnesium (Mg), sodium (Na) and trace metals such as lithium (Li), vanadium (V), chromium (Cr), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), molybdenum (Mo), cadmium (Cd), thallium (Tl) and lead (Pb) by using analytical techniques such as IC, ICP-OES and ICP-MS. The same samples were also investigated for other parameters such as pH, temperature, EC, TH, TDS, Na % and SAR. The WHO (2008), SANS 241 (2006) and Canadian guideline (2017) were used as a water quality guideline for drinking purposes.
Higher concentrations of Li, V, Cr, Ni, Cu, Zn, Al, Ca, Mg, K and Na in river water were detected in rainy season, whereas higher concentrations of As, Mo, K and Fe were recorded in dry season. The concentration of F-, Cd, Tl and Pb showed low contamination level in river samples. The results demonstrated that Tshipise river water was contaminated with high concentration of parameters: TDS (1864.0.8-3372.8 mg L-1), EC (2960.3-5270 mS cm-1), F- (6.403-8.419 mg L-1), SO42- (289.657-326.598 mg L-1), Na (836.690-922.810 mg L-1) and As (10.017-11.267 μg L-1) and relative to the (WHO) water guidelines. Nwanedi river also showed higher values of EC (298.0-699.0) mS cm-1 and TDS (190.3-447.5) mg L-1. In this study, the results indicated that water from Tshipise and Nwanedi river is not suitable for human consumption based on the guidelines of drinking water. The results also indicated that the soil sample had abundance of Ca, Al, Mn and Fe with concentration ranging from 0.13-10595, 0.0084-4.16, 0.0455-1116.5, 2.4-287404 mg Kg-1 respectively. / NRF
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