Dissertations / Theses on the topic 'Ground and surface water environments'
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Kikuchi, Colin. "Spatially Telescoping Measurements for Characterization of Ground Water - Surface Water Interactions along Lucile Creek, Alaska." Thesis, The University of Arizona, 2011. http://hdl.handle.net/10150/202976.
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A new spatially telescoping approach was proposed to improve measurement flexibility and account for hydrologic scale in field studies of groundwater-surface water (GW-SW) interaction. We applied this spatially telescoping approach in a study GW-SW interactions along Lucile Creek, Alaska. Catchment-scale data were used to screen areas of potentially significant GW-SW exchange, indicating groundwater contribution from a deeper regional aquifer along the middle to lower reaches of the stream. This initial assessment was tested using reach-scale estimates of groundwater contribution during base flow conditions. The reach-scale measurements indicated a large increase in discharge along the middle reaches of the stream accompanied by a shift in chemical composition towards a regional groundwater end member. Point measurements of vertical water fluxes were used to evaluate spatial and temporal variability of GW-SW exchange within representative reaches. The spatially telescoping approach identified locations of GW-SW exchange and improved interpretation of reach-scale and point-scale measurements.
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Colgan, Gary A. "Estimating surface/ground-water mixing using stable environmental isotopes." Thesis, The University of Arizona, 1989. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_etd_hy0042_m_sip1_w.pdf&type=application/pdf.
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Zwierschke, Kerry Hughes. "IMPACT OF TURFGRASS SYSTEMS ON THE NUTRIENT STATUS OF SURFACE WATER, AND GROUND WATER." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1235150457.
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Zhu, Danyun. "Determination of Residential-Use Turf Pesticides in Surface and Ground Water by HPLC/DAD." Fogler Library, University of Maine, 2003. http://www.library.umaine.edu/theses/pdf/ZhuD2003.pdf.
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Sloan, William Taylor. "Up-scaling hydrological processes and the development of a large-scale river basin modelling system." Thesis, University of Newcastle Upon Tyne, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.299643.
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Lee, Ronald Sang. "A physical assessment of Snake Pond of Cape Cod, Massachusetts, including a thermal and surface/ground water model." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/42686.
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Dara, Rebwar Nasir. "Using Ground Penetrating Radar (GPR) for identifying floodplain and riverbed structural heterogeneity and implications for groundwater-surface water exchange." Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8016/.
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The aim of the study is to investigate the variability in riverbed permeability fields in an unprecedented spatial resolution and quantify the impacts on controlling hyporheic exchange fluxes. Geophysical surveys were conducted deploying GPR on the floodplain and within the channel. At locations identified to be representative for the range of streambed hydrofacies in investigated stream reach, multi-level mini-piezometer networks were installed in the streambed. The results of GPR surveys in both sites provided different radar reflections which indicated a range of different radar facies and helped to delineate the type and extend of high and low conductive materials. The localised high Darcy fluxes inside high conductivity piezometers indicated rapid discharge of groundwater due to the enhanced connectivity to deeper groundwater. Whereas, low flow velocity within and around low conductivity peat and clay lenses indicated that these layers substantially inhibit groundwater upwelling, resulting in enhanced streambed residence and reaction times. The increase in residence time and the related depletion in the volume of DO facilitated the development of conditions necessary for nitrate reduction. In contrast, preferential flow paths and short residence times in highly conductive drift deposits resulted in no significant changes in nitrate concentrations along hyporheic flow paths.
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Kgomotso, Phemo Karen. "Global environmental agreements and local livelihoods : how the internationalisation of environmental resources shapes access to and control over wetland resources in the Okavango Delta, Botswana." Thesis, University of Sussex, 2011. http://sro.sussex.ac.uk/id/eprint/38451/.
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This thesis examines how global environmental crisis narratives and discourses have influenced environmental policy and practice in conservation programmes for the Okavango Delta, Botswana. In particular, it highlights the contested nature of biodiversity conservation and the embedded power relations in the framing, definition and crafting of solutions to the problem of biodiversity degradation at local, national and international levels. The thesis therefore examines, based on these framings, the consequences of global environmental agreements, such as the Ramsar Convention and the UN Convention on Biological Diversity, for local livelihoods in terms of access to and control over local environmental resources in the Okavango Delta. Using a political ecological conceptual lens and related literature on common pool resource management and community-based natural resource management, this thesis traces the changing perceptions, narratives and discourses relating to the Okavango Delta over time, and assesses how these have shaped changes in policy for the Delta's use and management. It specifically analyses the implementation of international programmes and their role in facilitating these changes. Through an in-depth study of dynamic human-environment interactions around fisheries and other wetland resources, this thesis shows how international interventions have not only increased conflicts but also facilitated the strict regulation of these resources. The thesis therefore analyses how framing these and other common pool resources as being of ‘international significance' alters control over them and affects the livelihood security of the local people that depend on these resources. It concludes that such restrictive conservation policies and management approaches have led to a transfer of control over wetland resources from local subsistence users to other, more powerful, commercial interests, especially those in the international tourism industry.
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Schoeman, Nika Anna. "Prevalence, characterisation and potential origin of Escherichia coli found in surface and ground waters utilized for irrigation of fresh produce." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/79801.
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Thesis (MSc Food Sc)--Stellenbosch University, 2013.ENGLISH ABSTRACT: Over the past two decades, there has been an increase in the use of water sources for irrigation, as well as an increase in Escherichia coli outbreaks linked to fresh produce. The full extent and type of E. coli contamination present in natural water sources is unknown and the contamination sources have also not been confirmed. The aim of this study was to enumerate and characterise E. coli from both irrigation water and potential contamination source sites. Total coliform and E. coli counts found in contamination source sites were as high as log 7.114 and log 6.912 MPN.100 mL-1, respectively. Total coliform and E. coli counts for irrigation sites were lower, with maximum counts of log 5.788 and log 5.768 MPN.100 mL-1, respectively. It was found that more than one third (5/14 = 35.71%) of the irrigation sites had E. coli counts exceeding the guidelines (<1 000 counts.100 mL-1) for ‘safe’ irrigation water for fresh produce (<1 000 counts.100 mL-1) as set by the Department of Water Affairs (DWA) and World Health Organisation (WHO), making the water unsuitable for the irrigation of fresh produce. Phylogenetic subgroups (A0, A1, B1, B22, B23, D1 and D2) and the MALDI Biotyper system (PCA dendrogram) were used to create a fingerprint of each E. coli isolated from the environment. These were then used to link E. coli strains from irrigation water to their most probable contamination origin. Escherichia coli population structure was found in this study, to be better suited for linking E. coli strains from irrigation water to their most likely source, than just applying the phylogenetic grouping. The MALDI Biotyper data in combination with the phylogenetic subgroup assignment was then used to group similar strains and link E. coli from irrigation water to their contamination sources by comparing population structures. Strains isolated from surface and groundwater showed similar distribution patterns, but groundwater strains showed a population structure more indicative of porcine and bovine origin, while surface water showed population characteristics which could not be used to make conclusive links between the irrigation water and suspected contamination sources. When investigating the population structures of individual sample sites, it was found that phylogenetic subgroups A0, A1 and B1 frequently made up the bulk of the E. coli population. It was also found that linking individual irrigation sites to contamination sources was successful, as irrigation site Berg-2 was found to have a similar population structure to contamination source site Plank-1 which represents human pollution from an informal settlement. This led to the conclusion that Berg-2 was being contaminated by human pollution, most probably from an informal settlement. Upon further investigation it was found that Berg-2 is downstream of an informal settlement, proving that E. coli population structure is a successful means of microbial source tracking (MST). Virulence factors of the 153 E. coli isolated during the study were identified and the potential risk associated with using the investigated irrigation water for irrigation of fresh produce, was determined. Two enteropathogenic E. coli (EPEC) strains were isolated from the irrigation water, one from the Plankenburg River water, and the other from a borehole in the Drakenstein area. The latter indicates that borehole water is not as safe as was once thought, and that there are bacterial contaminants finding their way into groundwater. The occurrence of an EPEC strain in river water shows that neither ground nor surface water is guaranteed to be safe, and that treatment of water being used for the irrigation of fresh produce should be implemented.
AFRIKAANSE OPSOMMING: Oor die afgelope twee dekades was daar nie net 'n toename in die gebruik van alternatiewe waterbronne vir besproeiing nie, maar ook 'n toename in uitbrake van Escherichia coli uitbrake wat aan vars produkte gekoppel kan word. Die tipe E. coli-besmetting wat in natuurlike waterbronne teenwoordig is, is onbekend en die besmettingsbron is ook nog nie bevestig nie. Daarom was die doel van hierdie studie om die voorkomssyfer van E. coli van beide besproeiingswater en potensiële kontaminasiebronne te bepaal, asook om die E. coli te karakteriseer. Totale kolivorme en E. coli-tellings wat in kontaminasiebronne gevind is, het ‘n maksimum van log 7,114 en log 6,912 MPN.100 mL-1 onderskeidelik bereik, terwyl die totale kolivorme en E. coli-tellings vir besproeiingswater laer was, met 'n maksimum van log 5,788 en 5,768 MPN.100 mL-1, onderskeidelik. Dit is bevind dat meer as 1/3 (5/14 = 35,71%) van die besproeiingswaterbronne meer E. coli bevat as wat toegelaat word in die riglyne vir "veilige" besproeiingswater vir vars produkte (<1 000 fekale koliforme.100 mL-1) wat deur die Departement Waterwese (DWA) en die Organisasie vir Wêreldgesondheid (WHO) aanbeveel word. Filogenetiese subgroepe (A0, A1, B1, B22, B23, D1 en D2) en die ‘MALDI Biotyper’-stelsel (PKA dendrogram) is gebruik om unieke profiele vir elke geïsoleerde E. coli te skep. Dié profiele is daarna gebruik om E. coli-stamme van besproeiingswater te koppel aan die mees waarskynlike oorsprong van kontaminasie. Daar is in hierdie studie bevind dat die E. coli-populasiestruktuur beter geskik was vir die koppeling van E. coli-stamme van besproeiingswater na hul mees waarskynlikste bron, as net die toepassing van die filogenetiese groepering. Dit was toe gevind dat E. coli wat uit oppervlak- en grondwater geïsoleer is, soortgelyke verspreidingspatrone het, maar grondwaterstamme se bevolkingstruktuur is meer aanduidend van fekale besmetting deur varke en beeste, terwyl oppervlakwater se bevolkingseienskappe nie duidelik genoeg was om ‘n gevolgtrekking oor moontlike bronne van besmetting te maak nie. Toe die populasiestruktuur van die individuele bemonsteringspunte ondersoek is, is daar bevind dat die filogenetiese subgroepe A0, A1 en B1 dikwels die meeste tot die E. coli bevolking bydra. Daar is ook bevind dat die koppeling van isolate in individuele besproeiingswaterbronne met hul mees waarskynlike bronne van kontaminasie suksesvol was. Besproeiingswater van Berg-2 het 'n soortgelyke populasiestruktuur as Plank-1 wat beskou is as ‘n kontaminasiebron. Dit het gelei tot die gevolgtrekking dat Berg-2 heel waarskynlik deur menslike besoedeling beïnvloed word, soos Plank-1, en dat daar moontlik ook ‘n informele nedersetting by Berg-2 betrokke is. Na verdere ondersoek is gevind dat Berg-2 inderdaad ook stroomaf van 'n ander informele nedersetting geleë is, wat bewys dat die E. coli-populasiestruktuur 'n suksesvolle manier is om E. coli kontaminasie te verbind met besproeiingswater. Patogeniese faktore, wat in E. coli voorkom en maagkieme veroorsaak, is vooraf getoets in elkeen van die 153 E. coli-isolate wat tydens die studie geïdentifiseer is. Twee ‘enteropathogenic’ E. coli (EPEC)-stamme is uit die besproeiingswater geïsoleer: een uit die Plankenburgrivier (Plank-3), en die ander uit 'n boorgat in die Drakenstein-gebied (Boorgat A1). Hierdie inligting dui aan dat boorgatwater nie so veilig is as wat voorheen vermoed is nie, en dat bakteriese kontaminasie wel vookom wat nie alleen die grondwater besmet nie, maar ook daarin oorleef. Die voorkoms van die EPEC-stamme in hierdie studie is ‘n aanduiding dat beide grond- en opppervlakwater ewe gevaarlik kan wees, en dat daar dus geen waarborg vir die veiligheid van die water is nie. Die behandeling van grond- en oppervlakwater, wat vir die besproeiing van vars produkte gebruik word, moet daarom ernstig oorweeg word om moontlike uitbrake van E. coli op vars produkte te verhoed.
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Li, Xuan. "Fate of Silver Nanoparticles in Surface Water Environments." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1320888780.
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Vionnet, Leticia Beatriz 1960. "Modeling of ground-water flow and surface water/ground-water interactions of the San Pedro River Basin, Cochise County, Arizona." Thesis, The University of Arizona, 1992. http://hdl.handle.net/10150/278134.
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Ground-water exploitation in the Upper San Pedro Basin has produced the formation of a cone of depression around the Sierra Vista-Fort Huachuca area. A portion of the mountain front recharge that otherwise would reach the San Pedro River is being intercepted by pumping, and portions of baseflow are being captured by pumping. The purpose of this study is to construct a simulation model capable of simulating the ground-water system as well as the ground-water-surface water interactions. The flow simulation was done by a three-dimensional, finite-difference ground-water flow model (MODFLOW) that incorporates a new stream-aquifer interaction package. Steady state simulations were performed to represent mean annual conditions. Transient simulations cover a 48 year period, starting in 1940 and ending in 1988. A sensitivity analysis of the steady state model was also performed.
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McCary, John. "Incorporating surficial aquifer ground-water fluxes into surface-water resource management studies." [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001095.
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Rosenberry, Donald O. "Influence of fluvial processes on exchange between ground water and surface water." Connect to online resource, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3284456.
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Anderson, Jacob. "Geochemical Tracers of Surface Water and Ground Water Contamination from Road Salt." Thesis, Boston College, 2013. http://hdl.handle.net/2345/3313.
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Thesis advisor: Rudolph HonThe application of road de-icers has lead to increasing solute concentrations in surface and ground water across the northern US, Canada, and northern Europe. In a public water supply well field in southeastern Massachusetts, USA, chloride concentrations in ground water from an unconfined aquifer have steadily risen for the past twenty years. The objectives of this study are to understand spatial and temporal trends in road salt concentrations in order to identify contamination sources and fate. To this end, the methods of this project include field and lab work. Water samples were collected from surface, near-surface, and ground water from March 2012 to March 2013. The other major field data are specific conductance measurements from probes located in three piezometers. In the lab, all samples were analyzed for major ions with ion chromatography analysis. Additionally, trace elements were measured by inductively coupled plasma analysis on a subset of samples. The results of these hydrogeochemical procedures showed several important trends. First, the highest concentrations of sodium and chloride from near-surface samples were located near to roadways. Second, ground water samples taken from glacial sediments contained relatively high concentrations throughout the water column, whereas ground water samples from wetlands had high concentrations only near the surface. Third, there was no clear relationship between pH and cation concentrations. Finally, specific conductance data showed strong seasonal trends near to the surface, whereas values taken from deeper in the aquifer were steadily increasing. Based on these results, it is highly probable that road salt application is the dominate contamination source. The pathways of road salt in the watershed include runoff into surface water and infiltration into the vadose zone and ground water. Road salt appears to preferentially travel through glacial features rather than floodplain features. It is possible that sodium from road salt is sorbed to aquifer sediment and displaces other cations. However, the low values of trace metals suggest that cation exchange is not mobilizing heavy metals. Finally, the increasing specific conductance values deep in the aquifer suggest that road salt is retained within the aquifer and concentrations will likely increase in the future if the current road salt application procedures are continued
Thesis (MS) — Boston College, 2013
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Earth and Environmental Sciences
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Chung, Ying-Hua. "Water behavior in different biological environments." Diss., University of Iowa, 2011. https://ir.uiowa.edu/etd/1213.
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In this thesis, we report on our studies of water dynamics and structure in various biological environments which include: the surfaces of proteins and various oligosaccharides, the intervening space between proteins; and in the vicinity of cryoprotectant disaccharides in the liquid and ice phases. From a theoretical perspective, we propose methodology to compute diffusivity and residence times on the surface of biomolecules. In particular our proposed algorithm to compute residence times appears to be better in dealing with poor statistics associated with the number of water molecules that remain on a surfaces for extended times. The type of linkage between monomers and the anomeric configuration all play a major role in determining the structure and dynamics of water on the surface of carbohydrates.
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Grundy, Ian H. "Air flow near a water surface /." Title page, table of contents and summary only, 1986. http://web4.library.adelaide.edu.au/theses/09PH/09phg889.pdf.
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Coes, Alissa L., and Alissa L. Coes. "A GEOCHEMICAL APPROACH TO DETERMINE GROUND-WATER FLOW PATTERNS IN THE SIERRA VISTA BASIN, ARIZONA, WITH SPECIAL EMPHASIS ON GROUND-WATER/SURFACE-WATER INTERACTION." Thesis, The University of Arizona, 1997. http://hdl.handle.net/10150/622969.
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Water quality in the Sierra Vista Ground-Water Basin is of extreme importance due to the basin's unique ecosystem and predicted future population growth. Portions of the Upper San Pedro River, flowing through the Sierra Vista Basin, contain some of the few remaining perennial streamflows in the southwest. Baseflow in the perennial reaches of the river are maintained almost entirely by the regional and floodplain aquifer systems. A population increase is predicted for the Sierra Vista Basin, and an impact on groundwater quality and availability can be expected. Due to the closely linked hydrologic systems within the basin, contamination or depletion of the regional aquifer could have direct implications for the San Pedro River. Water samples were collected within the study area from the regional and floodplain aquifers, the San Pedro River, and a bedrock spring in the Huachuca
Mountains. Samples were analyzed for field parameters, major-ions, and stable isotopes to describe the main chemical characteristics of the hydrologic systems within the basin. Analysis of regional aquifer geochemistry indicates a ground-water system strongly controlled by calcite precipitation. Specific conductance, deuterium and oxygen-18 values indicate a mixing of regional-aquifer ground water and San Pedro River surface water within the floodplain aquifer. Estimates of inflow to perennial reaches of the floodplain aquifer from the regional aquifer vary from 50 to 80%, depending on location. Inflow to the San Pedro River at Charleston from the regional aquifer is estimated to be about 50 to 70% of the stream discharge.
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Nam, Kijin. "Optimization of paths and locations of water quality monitoring systems in surface water environments." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/24745.
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Thesis (Ph.D.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2009.Committee Chair: Aral, Mustafa; Committee Member: Guan, Jiabao; Committee Member: Kim, Seong-Hee; Committee Member: Roberts, Philip; Committee Member: Uzer, Turgay.
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Vionnet, Leticia Beatriz, Thomas III Maddock, and David C. Goodrich. "Investigations of stream-aquifer interactions using a coupled surface-water and ground-water flow model." Department of Hydrology and Water Resources, University of Arizona (Tucson, AZ), 1997. http://hdl.handle.net/10150/615700.
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A finite element numerical model is developed for the modeling of coupled
surface-water flow and ground-water flow. The mathematical treatment of subsurface
flows follows the confined aquifer theory or the classical Dupuit approximation for
unconfined aquifers whereas surface-water flows are treated with the kinematic wave
approximation for open channel flow. A detailed discussion of the standard approaches to
represent the coupling term is provided. In this work, a mathematical expression similar
to Ohm's law is used to simulate the interacting term between the two major hydrological
components. Contrary to the standard approach, the coupling term is incorporated
through a boundary flux integral that arises naturally in the weak form of the governing
equations rather than through a source term. It is found that in some cases, a branch cut
needs to be introduced along the internal boundary representing the stream in order to
define a simply connected domain, which is an essential requirement in the derivation of
the weak form of the ground-water flow equation. The fast time scale characteristic of
surface-water flows and the slow time scale characteristic of ground-water flows are
clearly established, leading to the definition of three dimensionless parameters, namely, a
Peclet number that inherits the disparity between both time scales, a flow number that
relates the pumping rate and the streamflow, and a Biot number that relates the
conductance at the river-aquifer interface to the aquifer conductance.
The model, implemented in the Bill Williams River Basin, reproduces the observed
streamflow patterns and the ground-water flow patterns. Fairly good results are obtained
using multiple time steps in the simulation process.
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Robinson, J. Mike. "Chemical and Hydrostratigraphic Characterization of Ground Water and Surface Water Interactions in Cache Valley, Utah." DigitalCommons@USU, 1999. https://digitalcommons.usu.edu/etd/6717.
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A series of five east-west and two north-south hydrostratigraphic cross sections were drawn from drillers' logs of water wells within the southern half of Cache Valley, Utah. These cross-sections demonstrate that ground water flow to streams is restricted by a continuous low- II permeability layer, nearly 100-feet thick. This layer was correlated to the lake-bottom deposits of the Bonneville (30,000 -13,000 years ago) and Little Valley (140,000 - 90,000 years ago) cycles of the ancient Lake Bonneville.
The most productive aquifers in the valley, collectively termed the principal aquifer , are in the southeast corner , approximately between Smithfield and Hyrum, and between the eastern valley margin and the valley center. Sands and gravels of the principal aquifer were deposited as alluvial fans and deltas by streams draining the Bear River Range.
Ground water chemistry in the principal aquifer system is of the calcium-magnesium bicarbonate type with total dissolved solids (TDS) averaging about 300 ± 100 mg/L. TDS and the relative proportions of sodium, potassium, and chloride increase down flowpath, from recharge areas in the east to discharge areas in the west.
Oxygen-18 (18O) and deuterium (D) analyses were performed on precipitation samples at three locations on the east valley benches, four surface water samples from streams entering the valley, and fourteen ground water samples from either wells or springs. Precipitation and surface water values generally plotted along the Global Meteoric Water Line (GMWL), although the precipitation values plotted significantly lower on the GMWL than the surface water values. Of the ground water samples, twelve from the principal aquifer generally clustered near the surface water data points, suggesting that water from streams, rather than infiltrating precipitation, recharges the principal aquifer.
Twelve ground water samples were analyzed for tritium. The tritium values of eight samples from wells or springs in the principal aquifer suggest recharge after 1952. Two samples with tritium values dating prior to 1952 are from wells in the principal aquifer, and two are from wells west of the principal aquifer.
Four samples were analyzed for 14C. Two of these wells were completed in the principal aquifer and two west of it. Correcting for partial carbon dilution, the age difference between the different areas is on the order of tens of thousands of years.
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Biddulph, Matilda. "Testing the efficacy of mitigation measures for reducing fine sediment and associated pollutant delivery to and through rivers in agricultural catchments of England." Thesis, University of Northampton, 2016. http://nectar.northampton.ac.uk/9543/.
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Agricultural intensification has contributed to the degradation of freshwaters in the UK, through enhanced delivery of fine sediment and associated contaminants, leading to sedimentation and eutrophication. European legislation (Water Framework Directive 2000/60/EC) and subsequent UK government initiatives such as Catchment Sensitive Farming (CSF) and Demonstration Test Catchments (DTC), aim to improve the quality of freshwaters. The DTC programme aims to find cost-effective ways to reduce agricultural diffuse water pollution. This study aimed to monitor rivers in the Hampshire Avon DTC with existing and planned mitigation measures, to measure the effectiveness of the mitigation measures, and to develop an experimental design for wider application for pollution mitigation. The methods used and tested in this study were a combination of affordable, replicable and sustainable methods (in-stream sediment collection and water quality monitoring), more complicated, expensive, analytical laboratory methods (particle size, loss-on-ignition, geochemistry, mineral magnetism, environmental radionuclides), and sediment source fingerprinting. The mitigation measures were: improvement to farm infrastructure, a wooded and a grassed riparian buffer, and a constructed wetland and in-stream pond treatment train. The improved farm infrastructure (resurfacing of a farm track, installation of a retention pond, improvements to a drainage ditch) effectively reduced inputs of sediment and associated contaminants to the river, however, this had little positive impact on the river due to greater importance of inputs from other sources. The riparian buffers were reducing fine sediment and associated contaminant inputs laterally and from upstream, however, the effectiveness of the riparian buffers was undermined by a lack of riparian buffers upstream and by sub-surface field drains. Combined analysis of the river from the farm infrastructure in the headwaters (farm scale) to the wooded riparian buffer downstream (sub-catchment scale) showed a change in the dominant source of sediment. This highlighted that an experimental design would require monitoring at varying spatial scales, as individual farm scale mitigation measures may have little impact on an entire sub-catchment due to the importance of other sources from a larger drainage area. The constructed wetland and instream pond were not effective at reducing longitudinal delivery of fine sediment and associated contaminants due to issues related to maintenance and design, emphasising the importance of appropriate targeting, design, and maintenance of mitigation measures. The results from this study showed that the methods used would be suitable as part of an experimental design for wider application. Although complex and expensive, sediment source fingerprinting is essential for determining appropriate and cost-effective mitigation at farm and sub-catchment scales. Monitoring of the sediment and water quality using the affordable, replicable and sustainable methods could be managed by farmers and landowners across a dense spatial area, at a high temporal frequency, to ensure sustainable effectiveness of mitigation. There is a need for more co-working between policy makers and scientists to ensure appropriate funding and timescales for research are provided, and with farmers and landowners to improve understanding and vested interest in the contribution of agriculture to the degradation of water quality.
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Hadley, Heidi K. "Hydrochemical Definition of Ground Water and Surface Water, with an Emphasis on the Origin of the Ground-Water Salinity in Southern Juab Valley, Juab County, Utah." DigitalCommons@USU, 1996. https://digitalcommons.usu.edu/etd/6706.
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As part of a U.S. Geological Survey study in Juab Valley in central Utah from 1991 to 1994, the chemistry of ground - and surface -water samples was determined. Total dissolved solids in the ground water of southern Juab Valley have historically been higher , in general, than ground water in other areas of Utah . Total dissolved solids for ground-water samples from this study ranged from 623 to 3,980 milligrams/liter. High-sulfate chemical data of previous studies suggested that the major source of ground-water salinity is the dissolution of gypsum (hydrous calcium sulfate ) from the Arapien Shale. Sulfur-34 to sulfur- 32 isotopic ratio data have confirmed that dissolved Arapien Shale is the major source of salinity in southern Juab Valley water.
This thesis study of southern Juab Valley had four main objectives: 1) define the present chemistry of the ground and surface water; 2) qualitatively determine the mineralogy of the Middle Jurassic Arapien Shale; 3) determine the major sources of salinity; and 4) determine the main flow path in the ground-water system. Chemical data show that the water in southern Juab Valley is predominantly of a calcium-magnesium-sulfate-bicarbonate composition. X-ray diffraction determined the mineralogy of the Arapien Shale as primarily calcite and quartz. Mineralogy of the acid-insoluble residue is illite, chlorite, quartz, and a trace of feldspar. Based on chemical, isotopic, and simple salt weight percent data, dissolution of gypsum is the major source of salinity in southern Juab Valley water. Using the chemical and isotopic data as input , a mass balance computer software program (NETPATH) helped to determine that the gypsum is derived from the Arapien Shale . NETPATH and the potentiometric surface map helped to define the main ground-water flow path as southwest across southern Juab Valley, from Chicken Creek in the San Pitch Mountains on the east side of the valley toward Chick Creek Reservoir in the southwest part of the valley.
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Fleming, Brandon J. "Effects of anthropogenic stage fluctuations on surface water/ground water interactions along the Deerfield River, Massachusetts." Amherst, Mass. : University of Massachusetts Amherst, 2009. http://scholarworks.umass.edu/theses/226/.
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Vionnet, Leticia Beatriz, and Thomas Maddock. "Modeling of Ground-Water Flow and Surface/Ground-Water Interaction for the San Pedro River Basin Part I Mexican Border to Fairbank, Arizona." Department of Hydrology and Water Resources, University of Arizona (Tucson, AZ), 1992. http://hdl.handle.net/10150/614152.
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Many hydrologic basins in the southwest have seen their perennial streamflows
turn to ephemeral, their riparian communities disappear or be jeopardized, and their
aquifers suffer from severe overdrafts. Under -management of ground -water exploitation
and of conjunctive use of surface and ground waters are the main reasons for these
events.
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Van, Metre Peter Chapman 1956, and Metre Peter Chapman 1956 Van. "Flow and water quality relations between surface water and ground water in the Puerco River basin near Chambers, Arizona." Thesis, The University of Arizona, 1990. http://hdl.handle.net/10150/277926.
Full textAbstract:
The Puerco River is an ephemeral stream that received effluent from uranium-mine dewatering operations from the 1950's until 1962 and from 1968 until mining ceased in 1986. Flow and water-quality relations between the Puerco River and the alluvial aquifer underlying it were investigated at a site near Chambers. Data collection included installing and sampling nine monitor wells and two drive points; monitoring stage and sampling surface water; and slug testing wells. The stream recharges the alluvial aquifer during periods of flow and the streambed is a location of ground-water discharge by evapotranspiration during periods of no flow. Discharge by evapotranspiration may exceed recharge thus reducing the potential for contaminant movement away from the river by advective transport. Geochemical modeling indicates that uranium minerals are undersaturated in the range in Eh observed. A +0.84 correlation was calculated relating dissolved uranium concentration to depth in monitor wells suggesting the stream is a source of uranium to the alluvial aquifer. (Abstract shortened with permission of author.)
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Neaville, Chris C. "Hydrogeology and simulation of ground-water and surface-water flow in Pinal Creek Basin, Gila County, Arizona." Thesis, The University of Arizona, 1991. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1991_400_sip1_w.pdf&type=application/pdf.
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Oztas, Nur Banu. "Pesticide Pollution In Surface And Ground Water Of An Agricultural Area, Kumluca, Turkey." Phd thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/3/12609445/index.pdf.
Full textAbstract:
Concentrations of 17 organochlorine and 14 organophosphorus pesticides were measured in 27 ground and 11 surface water samples collected from a heavily agricultural area, Kumluca, in spring and fall seasons of 2005. The samples were preconcentrated by Solid Phase Extraction. GC-ECD and GC-NPD systems were used for quantitative determination of organochlorine and organophosphorus pesticides respectively.
The quality check/quality assurance tests were performed by the analysis of field and laboratory blanks, standard reference materials, spiked control and sample matrices, surrogate standards, sampling and analysis replicates. It is observed that, sample matrix lowers average percent recoveries from 89% to 76%.
The uncertainties of measurements were calculated to determine major factors affecting the analysis results. It was observed that uncertainty arising from extraction procedure was generally the highest.
The most commonly observed pesticide was endosulfan (70%) and chlorpyriphos (53%) for organophosphorus and organochlorine pesticides. The highest average concentration was observed for heptachlor (26 ng/L) and fenamiphos (184 ng/L).
Generally pesticides were detected more often in surface waters, where the concentrations were also higher. The concentrations of organophosphorus pesticides in spring, and organochlorine pesticides in fall season were higher.
The high occurrences and detection of degradation products of chlorinated pesticides clearly indicate their intense use before 1980s. It is shown that, in Kumluca environment, degradation of these pesticides mostly occurs in surface waters.
It is observed that agricultural activities affect water quality in the region. The total concentration limit (500ng/L) was exceeded for 27% of surface and 14% of ground water samples, at least once in both seasons. The legal limit for a single pesticide (100ng/L) was exceeded by 32 % of surface, 24 % of ground water samples.
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Lauwo, Simon Yesse. "A modeling investigation of ground and surface water fluxes for Konza Tallgrass Prairie." Thesis, Manhattan, Kan. : Kansas State University, 2007. http://hdl.handle.net/2097/470.
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Cairampoma, Arroyo Alberto, and Vega Paul Villegas. "Legal regime ground water in Peru." THĒMIS-Revista de Derecho, 2017. http://repositorio.pucp.edu.pe/index/handle/123456789/108913.
Full textAbstract:
This article studies the legal regime of groundwater by analyzing the context of integrated water resources management and recognizing its definition and characteristics.Furthermore, it analyses the ownership of ground water, the planning regime applicable, the exploration and exploitation activities, their authorization certificates, the activity of supervision over them, and finally the article describes the special schemes for management and limitation recognized in Peruvian law.En el presente artículo se estudia el régimen jurídico de las aguas subterráneas, analizando el marco de la gestión integrada de recursos hídricos y reconociendo su definición y particularidades.Asimismo, se analiza la titularidad de las aguas subterráneas, el régimen de planificación aplicable, las actividades de exploración y explotación, sus títulos habilitantes, la actividad de supervisión que sobre ellas recae, para finalmente, dejar anotados los regímenes especiales de gestión y limitación reconocidos en el ordenamiento jurídico peruano.
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Mathipa, Morongwa Mary. "Analysis of the bio-physicochemical quality of surface and ground water in the Tubatse Municipality." Thesis, University of Limpopo, 2016. http://hdl.handle.net/10386/1663.
Full textAbstract:
Thesis (M. Sc. (Microbiology)) -- University of limpopo, 2016Human activities are known to be the major contributors to contamination of natural water sources. This becomes a serious health risk when the communities rely on the same water sources for their household water needs. The current study investigated the bio-physicochemical quality of surface and ground waters found in a mining area in the Tubatse locality, for their suitability for drinking and other household use. The bacteriological analyses of surface waters showed dominance by genera of the phylum Proteobacteria, followed by Actinobacteria and Firmicutes. The isolates included the genera Aeromonas, Pseudomonas, Cronobacter, Acinetobacter, Enterobacter, Pantoea, Serratia, Bordetella, Kocuria and Streptococcus. This dominance pattern is proportionately similar to the pattern reported on human skin and of gut biota. Enterobacter spp. were the predominant species in the surface waters, followed by Bordetella spp. With regard to ground water, one sample was laden with coliforms whereas the other sample was free of coliforms. Physical quality parameters such as turbidity, colour and (total suspended solids) TSS of the surface and ground water samples were compliant with the set standards for drinking water according to South African water quality guidelines (2005). The concentrations of Zn, [SCN-], Cr, Co, Fe, Ni, Cu, H2O2, Cl2 were determined in the surface and ground waters in dry and wet seasons as well. A non-significant decrease in the levels of Cl2 and [SCN-] and an increase in TDS and Cr were observed in the wet season. All metal and chemical levels in surface and ground water, except Cr, were lower than permitted concentration for drinking water. However the concentrations of Zn, Fe and Co exceeded the normal expected concentrations of < 3.5 μg/L, 0.5 mg/L, < 0.01 mg/L and < 5 μg/L respectively. The sediments and soil samples were digested with aqua regia for Cu, Cr, Fe, Co and Zn analyses. An increase in the levels of Zn, Cr and Co in the wet season was observed. The concentrations of the heavy metals such as Co, Cu and Cr were higher in sediments at the sampling points closer to the mining sites. Cytotoxicity assay was performed with different concentrations, as detected in the water and sediment samples, of Zn, [SCN-], Cr, Co, and Fe on C2C12 (mammalian) cells. An increase in viable cells was observed after treatment with Cr (0.2, 0.45 and 0.9 mg/L), Zn and Fe (1.0 and 2 mg/L), Co (2, 5 and 10 mg/L). Only cells treated with SCN- (3.3, 5.4 and 7.2 mg/L) exhibited a significant decrease in viability. These results demonstrate that the water in the Tubatse municipality is not suitable for drinking and other household purposes without prior treatment which will remove contaminating microorganisms and chemicals and heavy metals.
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Davis, Laura Agnes. "Ground-Water Flow and Interaction with Surface Water in San Bernardino Valley, Cochise County, Arizona and Sonora Mexico." Thesis, The University of Arizona, 1997. http://hdl.handle.net/10150/191298.
Full textAbstract:
In the center of San Bernardino Valley in southeastern Arizona, San Bernardino National Wildlife Refuge provides unique wetlands habitat for endangered fish and wildlife. Confined conditions exist within the refuge, producing springs, artesian wells, and perennial pools along Black Draw, the main surface-water drainage. A numerical flow model was constructed in order to understand the hydrogeologic system of the basin. Annual inflows to the basin include 50,171 acre-feet of mountain-front recharge, 4,360 acft of underflow, and 7,074 ac-ft of river leakage. Annual outflows consist of 57,704 ac-ft of underflow, 3,010 ac-ft of river leakage, 537 ac-ft of evapotranspiration, 346 ac-ft of spring discharge, and 5 ac-ft of stream leakage. Further investigations are needed to refine the annual steady-state model, develop a seasonal (oscillatory) model, and construct transient simulations predicting responses of the hydrologic system to climatic and/or anthropogenic stresses. Extremely large mountain-front recharge and subsurface outflow estimates should be improved by conducting pump tests, geophysical studies, and isotope dating and chemistry analyses of ground water, and by collecting more water levels in Sonora. These studies will also provide information on the role of basalt flows in mountain-front recharge distribution and ground-water flow patterns. The study concludes with a recommended monitoring program for the refuge.
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Davis, Laura Agnes, Thomas III Maddock, and Robert Mac Nish. "Ground-water flow and interaction with surface water in San Bernardino valley, Cochise county, Arizona and Sonora, Mexico." Department of Hydrology and Water Resources, University of Arizona (Tucson, AZ), 1997. http://hdl.handle.net/10150/615699.
Full textAbstract:
In the center of San Bernardino Valley in southeastern Arizona, San Bernardino
National Wildlife Refuge provides unique wetlands habitat for endangered fish and
wildlife. Confined conditions exist within the refuge, producing springs, artesian wells,
and perennial pools along Black Draw, the main surface-water drainage. A numerical
flow model was constructed in order to understand the hydrogeologic system of the basin.
Annual inflows to the basin include 50,171 acre-feet of mountain-front recharge, 4,360 acft
of underflow, and 7,074 ac-ft of river leakage. Annual outflows consist of 57,704 ac-ft
of underflow, 3,010 ac-ft of river leakage, 537 ac-ft of evapotranspiration, 346 ac-ft of
spring discharge, and 5 ac-ft of stream leakage. Further investigations are needed to refine
the annual steady-state model, develop a seasonal (oscillatory) model, and construct
transient simulations predicting responses of the hydrologic system to climatic and/or
anthropogenic stresses. Extremely large mountain-front recharge and subsurface outflow
estimates should be improved by conducting pump tests, geophysical studies, and isotope
dating and chemistry analyses of ground water, and by collecting more water levels in
Sonora. These studies will also provide information on the role of basalt flows in
mountain-front recharge distribution and ground-water flow patterns. The study
concludes with a recommended monitoring program for the refuge.
33
Neish, Catherine Dorothy. "Formation of Prebiotic Molecules in Liquid Water Environments on the Surface of Titan." Diss., The University of Arizona, 2008. http://hdl.handle.net/10150/194180.
Full textAbstract:
Saturn’s moon Titan represents a unique locale for studying prebiotic chemistry. Reactions occurring in its thick nitrogen-methane atmosphere produce a wide variety of carbon, hydrogen, and nitrogen containing organic molecules. If these molecules are exposed to liquid water, they may react further to produce oxygen-containing species, a key step in the formation of terrestrial biomolecules. On average, Titan's surface is too cold for liquid water. However, models indicate that melting caused by impacts and/or cryovolcanism may lead to its episodic availability. One possible cryovolcanic dome, Ganesa Macula, was identified in early observations by the Cassini spacecraft. In this work, I estimate the height and morphology of this feature using a synthetic aperture radar (SAR) image. I then use a thermal conduction code to calculate the freezing timescale for an initially liquid dome, yielding freezing timescales of ~10² - 10⁵ years. To determine how far aqueous organic chemistry can proceed in liquid water environments on Titan, I measure the rate coefficients of Titan analogue organic molecules ("tholins") with low temperature aqueous solutions to produce oxygenated species. These reactions display first-order kinetics with half-lives between 0.4 and 7 days at 273 K (in water) and between 0.3 and 14 days at 253 K (in 13 wt. % ammonia-water). Tholin hydrolysis in aqueous solutions is thus very fast compared to the freezing timescales of impact melts and volcanic sites on Titan, which take hundreds to thousands of years to freeze. The fast incorporation of oxygen, along with new chemistry made available by the introduction of ammonia, may lead to the formation of molecules of prebiotic interest in these transient liquid water environments. This chemistry makes impact craters and cryovolcanoes important targets for future missions to Titan.
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Syaukat, Yusman. "Economics of integrated surface and ground water use management in the Jakarta region, Indonesia." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0028/NQ51048.pdf.
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Pullan, Stephanie. "Modelling of pesticide exposure in ground and surface waters used for public water supply." Thesis, Cranfield University, 2014. http://dspace.lib.cranfield.ac.uk/handle/1826/8605.
Full textAbstract:
Diffuse transfers of pesticides from agricultural land to ground and surface waters can lead to significant drinking water quality issues. This thesis describes the development and application of a parameter-efficient, numerical model to predict pesticide concentrations in raw water sources within an integrated hydrological framework. As such, it fills an unoccupied niche that exists in pesticide fate modelling for a computationally undemanding model that contains enough process complexity to be applicable in a wide range of catchments and hydrogeological settings in the UK and beyond. The model represents the key processes involved in pesticide fate (linear sorption and first-order degradation) and transport (surface runoff, lateral throughflow, drain flow, percolation to the unsaturated zone, calculated using a soil water balance) in the soil at a daily time step. Soil properties are derived from the national soil database for England and Wales and are used to define the boundary conditions at the interface between the subsoil and the unsaturated zone. This is the basis of the integrated hydrological framework which enables the application of the model to both surface water catchments and groundwater resources. The unsaturated zone model accounts for solute transport through two flow domains (accounting for fracture flow and intergranular matrix flow) in three hydrogeological settings (considering the presence and permeability of superficial deposits). The model was first applied to a small headwater sub-catchment in the upper Cherwell. Performance was good for drainflow predictions (Nash Sutcliffe Efficiency > 0.61) and performed better than the MACRO model and as well as the modified MACRO model. Surface water model performance was evaluated for eight pesticides in five different catchments. Performance was generally good for flow prediction (Nash Sutcliffe Efficiency > 0.59 and percentage bias below 10 %, in the validation period for all but two catchments). The 90th percentile measured concentration was captured by the model in 62 % of catchment-pesticide combinations. In theremaining cases predictions were within, at most, a factor of four of measured 90th percentile concentrations. The rank order of the frequency of pesticides detected over 0.1 μg L-1 was also predicted reasonably well (Spearman’s rank coefficient > 0.75; p < 0.05 in three catchments). Pesticide transport in the unsaturated zone model was explored at the point scale in three aquifers (chalk, limestone and sandstone). The results demonstrate that representing the unsaturated zone processes can have a major effect on the timing and magnitude of pesticide transfers to the water table. In comparison with the other catchment scale pesticide fate models that predict pesticide exposure at a daily time-step, the model developed stands out requiring only a small number of parameters for calibration and quick simulation times. The benefit of this is that the model can be used to predict pesticide exposure in multiple surface and groundwater resources relatively quickly which makes it a useful tool for water company risk assessment. The broad-scale approach to pesticide fate and transport modelling presented here can help to identify and prioritise pesticide monitoring strategies, to compare catchments in order to target catchment management and to highlight potential problems that could arise under different future scenarios.
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Cho, Jae-Pil. "A comprehensive modeling approach for BMP impact assessment considering surface and ground water interaction." Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/27890.
Full textAbstract:
The overall goal of this study was to develop a comprehensive tool for assessing the effectiveness of selected BMPs on both hydrology and water quality and to demonstrate the applicability of the system by considering 1) temporally and spatially changing land use management practice in an agricultural watershed and 2) interaction between surface and ground water over the entire system. A user interface and Dynamic Agricultural Non-point Source Assessment Tool (DANSAT) were developed to achieve this goal. DANSAT is the only distributed-parameter, physically-base, continuous-simulation, and multi-soil layer model for simulating impacts of agricultural BMPs on hydrology and water qulality in small agricultural watersheds. DANSAT was applied to QNB plot (18m à 27m) and two agricultural watersheds in Virginia, including Owl Run watershed (1140 ha) and QN2 in the Nomini Creek watershed (216 ha), to evaluate the model components and its performance in predicting runoff, sediment yield, and pesticide load. DANSAT performed well in predicting total runoff and temporal variations in surface runoff for both field-scale and watershed-scale applications. Total percent errors between the measured and predicted results were less than 10% except for one case (39.8% within a subwatershed of Owl Run watershed), while the daily Nash-Sutcliffe model efficiencies were greater than 0.5 in all applications. Predicted total sediment yields were within ±35% of observed values in all applications. However, the performance of DANSAT in predicting temporal trend and spatial distribution of sediment loads was acceptable only within Owl Run watershed, where high correlations between flow rates and sediment loads exist. The predicted total pesticide loads were within ±100% of observed values. DANSAT failed to simulate the temporal occurrence of pesticide loads with a 0.42 daily Nash-Sutcliffe efficiency value. The Dual-Simulation (DS) was developed within the linked ground water approach to resolve problems encountered due to the existence of different temporal scales between DANSAT and the existing ground water models such as MODFLOW and MT3D. The linked approach performed better in predicting the seasonal trend of total runoff compared to the integrated approach by showing an increase in monthly Nash-Sutcliffe efficiency value from 0.53 to 0.60. Surface and subsurface output variables were sensitive to the changes in spatially distributed soil parameters such as total porosity and field capacity. A maximum grid size of 100 m was recommended to be appropriate for representing spatial distribution of topographic, land use, and soil characteristics based on accuracy analysis during the GIS manipulation processes. Larger time-step based on predefined acceptable maximum grid size, decreased the computational time dramatically. Overall sensitivity to different grid sizes and time-steps was smallest for hydrology components followed by sediment and pesticide components. Dynamic crop rotation was considered by DANSAT, and the model successfully simulated the impacts of temporal and spatial changes in crop rotations on hydrology and water quality for both surface and subsurface areas. DANSAT could prove to be a useful tool for non-point source pollution managers to assess the relative effectiveness of temporally and spatially changing BMPs on both surface and ground water quantity and quality.Ph. D.
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Nalesso, Mauro. "Integrated Surface-Ground Water Modeling in Wetlands With Improved Methods to Simulate Vegetative Resistance to Flow." FIU Digital Commons, 2009. http://digitalcommons.fiu.edu/etd/122.
Full textAbstract:
This dissertation focused on developing an integrated surface – subsurface hydrologic simulation numerical model by programming and testing the coupling of the USGS MODFLOW-2005 Groundwater Flow Process (GWF) package (USGS, 2005) with the 2D surface water routing model: FLO-2D (O’Brien et al., 1993). The coupling included the necessary procedures to numerically integrate and verify both models as a single computational software system that will heretofore be referred to as WHIMFLO-2D (Wetlands Hydrology Integrated Model). An improved physical formulation of flow resistance through vegetation in shallow waters based on the concept of drag force was also implemented for the simulations of floodplains, while the use of the classical methods (e.g., Manning, Chezy, Darcy-Weisbach) to calculate flow resistance has been maintained for the canals and deeper waters. A preliminary demonstration exercise WHIMFLO-2D in an existing field site was developed for the Loxahatchee Impoundment Landscape Assessment (LILA), an 80 acre area, located at the Arthur R. Marshall Loxahatchee National Wild Life Refuge in Boynton Beach, Florida. After applying a number of simplifying assumptions, results have illustrated the ability of the model to simulate the hydrology of a wetland. In this illustrative case, a comparison between measured and simulated stages level showed an average error of 0.31% with a maximum error of 2.8%. Comparison of measured and simulated groundwater head levels showed an average error of 0.18% with a maximum of 2.9%.
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Schmid, Wolfgang, and Wolfgang Schmid. "A farm package for modflow-2000: Simulation of irrigation demand and conjunctively managed surface-water and ground-water supply." Thesis, The University of Arizona, 2004. http://hdl.handle.net/10150/626888.
Full textAbstract:
A new Farm Package (FMP) was developed for using the U.S. Geological Survey's
groundwater modeling program, MODFLOW-2000 (MF2K), to estimate irrigation water
allocations to irrigation settings. The FMP dynamically integrates irrigation water
demand, surface-water & groundwater supply, and return flow from excess irrigation.
Routed surface-water delivery is optional, and can be simulated by coupling FMP with
the Streamflow Routing Package (SFRl ).
MF2K with FMP and SFRl allows estimating the allocation of surface-water and
groundwater to farms for the following applications: (1) historic and future simulations,
(2) water rights issues and operational decisions, (3) non-drought and drought situations.
Irrigation demand, supply, and return flow are partly subject to head-dependent sinks
and sources such as transpiration uptake from groundwater (formulated by FMP) and
leakage between the conveyance system and the aquifer (formulated by SFRl).
A steady state transpiration uptake, varying with changing water level, is stepwise
linearly approximated by FMP. This was validated by ensembles of variably saturated
soil column models using HYDRUS2D for different soil types, values of potential
transpiration, and root zone depths. A restriction of transpiration uptake is proportional to
a reduction of the active root zone. It is approximated in FMP by an analytical solution,
which determines inactive ranges of the root zone with pressure heads typical for
conditions of anoxia or wilting. At steady state, the transpiration uptake equaled the flux across the water table (plus
the irrigation flux, if applied). Therefore, changes in soil water storage are assumed
negligible. Based on this assumption, the irrigation flux required is determined in FMP
by subtracting transpiratory components from natural sources (groundwater,
precipitation) from a maximum transpiration uptake. This transpiratory irrigation
requirement is calculated for each finite difference cell, and increased sufficiently to
compensate for evaporative losses and for inefficient use. Accumulating the resulting cell
delivery requirement over all cells in a farm yields the total farm delivery requirement,
which is to be satisfied with surface- or groundwater.
Five economic and non-economic drought response policies can be applied, if the
potential supply of surface- and groundwater is insufficient to meet the crop demand.
The code was verified by a hypothetical example problem run in 55 scenarios (5
drought policy scenarios x 11 parameter-group scenarios). Among all sources and sinks
in a cumulative volumetric budget, 'farm well discharge,' and particularly 'farm net
recharge,' were most sensitive to changes in drought policies or changes of parameters.
39
Schmid, Wolfgang. "A farm package for MODFLOW-2000 simulation of irrigation demand and conjunctively managed surface-water and ground-water supply /." Diss., The University of Arizona, 2004. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_2004_287_sip1_w.pdf&type=application/pdf.
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Moakes, Greg. "Study of Lithium Solvation Environments in Water-saturated Nitrobenzene." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/14105.
Full textAbstract:
It was found that there exist three major water environments when water is dissolved in nitrobenzene. 2H NMR has proved that these solvatomers exist irrespective of whether lithium salt is added to the system. 7Li NMR experiments suggested that the first solvatomer is majority nitrobenzene, the second a mixed solvation shell consisting of nitrobenzene and water and the third solvatomer is a large water aggregated at the glass surface. The mixed solvation state is short lived and is promoted by addition of water of by supersaturating the system upon cooling. This is a high energy state and decays either into the homogenous bulk NB state or to the surface of the glass wall, depending on if glass surface is present. In the 7Li NMR experiments, the hydrophobicity of the salt, determined by the anion, affects the relative intensity of the three 7Li resonances.
Addition of lithium serves to promote hydrogen bonding in the majority nitrobenzene solvatomer, as confirmed by FTIR and neutron diffraction studies. There is no evidence that it has an effect on the size of the mixed solvatomer or the water aggregate immobilized on the glass surface. A reasonable hypothesis is that lithium exchanges between the water species which are formed independent of lithium involvement. The system is summarized as follows:
Below critical water concentration (~200mM) nitrobenzene/water is a homogeneous distribution of water molecules in nitrobenzene. Addition of lithium salt to such a system has two main affects. First, the lithium promotes hydrogen bonding between the dissolved water molecules, as confirmed by FTIR and neutron scattering. Second, the hydrogen bonded water may precipitate causing microheterogeneity of the system, leading to a second resonance observed in both the 2H and 7Li NMR spectra (LiNB/W). In the presence of glass, a third solvation state can nucleate at the glass surface; this solvation state has character even closer to that of bulk water (LiW). These two supplementary solvation states can be artificially induced by either adding aliquots of water or cooling.
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Schock, Kevin A. "Predicting Seepage of Leachate from the St. Johns Landfill to Ground and Surface Water Systems." PDXScholar, 1993. https://pdxscholar.library.pdx.edu/open_access_etds/4648.
Full textAbstract:
Determination of the vertical and horizontal groundwater hydraulic gradient within a landfill is the first step in determining the potential of groundwater contamination from the landfill leachate. The length of a study and the frequency at which measurements are recorded can greatly affect the description of the local groundwater environment. A more comprehensive analysis can be preformed for longer periods of study and greater measurement frequency. The intent of this study was to install a continuous groundwater level monitoring system around the st. Johns Landfill for a minimum study length of one year. This would allow a more thorough study of the seasonal character and behavior of the groundwater system beneath the landfill than in previous studies. Particular interest was paid to groundwater level changes resulting from seasonal weather changes. Additional attention was paid to other forcing mechanisms which could be perturbing groundwater levels, and variations in the geochemical groundwater constituents. Included throughout this report is a literature review of various studies pertinent to the analysis of groundwater level variations. Seasonal variations in vertical groundwater hydraulic gradients were reviewed and time averaged vertical seepage rates were estimated. Areal plots of groundwater levels were used to view expected horizontal groundwater hydraulic gradients during seasonal maximum and minimum groundwater levels. A computer model was developed to study the effects temporal variations in slough water levels had on groundwater seepage rates through the perimeter dike separating the landfill from the sloughs. The modeling provided an estimate of the average horizontal leachate seepage rate into the sloughs. Comparison plots of monitoring well groundwater levels were used to analyze potential swash zones beneath the landfill and potential effects of lowered water levels in Bybee Lake. Spectral analysis techniques were imployed to determine the dominant frequencies observed in the groundwater levels, allowing determination of the type of forcing mechanism driving the fluctuations. Geochemical groundwater constituents were statistically analyzed to determine the significance of observed trends in the data: areal plots of chloride concentrations and electrical conductivity were made to view constituent distributions within the underlying aquifers. Estimated vertical and horizontal groundwater seepage rates into the local waters showed that horizontal leachate seepage is insignificant compared to vertical leachate seepage. Groundwater level comparison plots indicated no significant swashing beneath the landfill occurred. The statistical studies on groundwater forcing mechanisms indicated that either the slough or the Columbia River water levels could be perturbing groundwater levels. Trend analyses on the geochemical groundwater constituents indicated significant, positive trends in chloride concentrations, and undeterminable trends in electrical conductivity.
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Powers, Craig W. "Monitoring the Transport of Microorganisms in Aquatic Environments Using Unmanned Surface Vehicles." Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/81961.
Full textAbstract:
The majority of the Earths surface is covered with water, and the air-water interface (AWI) acts as the natural boundary between the atmosphere and the water. The AWI is an important ecological zone in natural aquatic habitats that governs transport of material and energy between bodies of water and the atmosphere. Little is known about temperature profiles and biological transport across the boundary layers at the air-water interface, and how wind interactions at the AWI affects them. New technologies such as sensors and unmanned surface vehicles (USV) need to be developed and used to address this knowledge gap. The goal of the research is to study population densities of the bacteria Pseudomonas syringae below, at and above the AWI using USV equipped with specialized sensors.
The first specific objective was to map temperature profiles and resolve the boundary layer at the AWI using high resolution distributed temperature sensing (HR-DTS) on board an unmanned surface vehicle (USV).
Our second research objective was to sample microbes from the water with a USV at multiple depths and locations.
Our third research objective was to sample microbes from the atmosphere with a USV at the AWI.
Our fourth research objective was to track and localize hazardous agents (tracer dyes) using a USV in aqueous environments.Ph. D.
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Holmes, Stuart W. "Investigation of Spatial and Temporal Groundwater Thermal Anomalies at Zanesville Municipal Well Field, Ohio: Implications for Determination of River-Aquifer Connectivity Using Temperature Data." Ohio University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1462026430.
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Pearce, Meryl Winsome. "Assessment of factors influencing the quality of surface and ground water in the Hout Bay river catchment." Thesis, Rhodes University, 1989. http://hdl.handle.net/10962/d1001900.
Full textAbstract:
An investigation into the quality of surface water and ground water was conducted during 1988 in the 38,8 km² Hout Bay River catchment near Cape Town. The main objective of the study was to determine those areas and activities which constitute a pollution source and to ascertain the relative proportion which each contributes to the pollution problem and health risk of the surf zone of the beach at Hout Ba . The objective was achieved by monitoring the chemical and microbiological attributes of the Hout Bay River, its tributaries and stormdrains in wet and dry conditions on a routine basis and during storm events. Hout Bay is a rapidly developing residential area in which sewage disposal occurs by means of septic tank soakaway systems. Ground water quality was monitored to investigate the contribution to contamination by septic tank effluent. Results showed that stormdrain effluent in dry and wet conditions and surface runoff during rainfall were the main vectors of pollution. Although the pollution concentration was high during dry conditions the greatest pollution discharge to the surf zone of Hout Bay occurred during storm events. In view of the proposed residential development it is imperative that pollution control measures be undertaken so as to secure the future recreational and aesthetic value of Hout Bay
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Jenkins, Michael Edward 1961. "Ground and surface water assessments supporting instream flow protection at the Hassayampa River Preserve, Wickenburg, Arizona." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277236.
Full textAbstract:
The Arizona Nature Conservancy's Hassayampa River Preserve is 50 miles northwest of Phoenix near the town of Wickenburg. Four miles of the largely ephemeral Hassayampa River are perennial within the preserve, supporting one of the finest remaining cottonwood-willow forests in the state. Stream flows are affected by wells pumping ground water directly from the alluvial aquifer and may be influenced by wells which intercept lateral inflow from the regional basin-fill aquifer. Developing effective management strategies to protect base flow conditions (∼4 cfs) depends on a clear understanding of the surface and ground-water systems in the preserve. Provided that ground water developers near Wickenburg recognize and incorporate the interconnected nature of each hydrologic system, perennial flow within the preserve is not believed to be immediately threatened. (Abstract shortened with permission of author.)
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Brasseur, Philippe. "Experimental Study of the Growth and Stable Water Isotopes of Ice Formed by Vapour Deposition in Cold Environments." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34487.
Full textAbstract:
Ice formed by water vapour deposition has been identified in different terrestrial environments: 1) in the atmosphere; 2) at the ground’s surface; 3) in caves; 4) in seasonally frozen ground; and 5) in perennially frozen ground (permafrost). Thus far, ground ice formed by diffusion and deposition of vapour in soils (types 4 and 5) has rarely been studied in a natural setting and remains one of the most poorly described ice types on Earth. This thesis focuses on the dynamics of deposition and sublimation of atmospheric water vapour into permafrost and the isotopic signature (D/H and 18O/16O) of the emplaced ground ice under different experimental conditions. Ground ice was produced in sediments with different thermo-physical characteristics (glass beads, JSC Mars-1 simulant). After a two-month growth period, the higher porosity sediments (JSC) had more than 7x the gravimetric water content than the lower porosity soil. Ground ice profiles had a distinct concave downwards shape due to the decrease in saturation vapour pressure with depth. Results also indicate that vapour deposited ground ice has a distinct δD-δ18O composition that plots near regression slope value of 8. Pore water isotopes plot below the global meteoric water line (GMWL) when the source of moisture is directly on top of the sediments. If an air gap is introduced between the source of moisture and the sediments, the pore water isotopes shift above the GMWL due to re-sublimation at the ground surface. Overall, this thesis addressed some fundamental knowledge gaps required to better understand the growth and isotopic evolution of ground ice emplaced by vapour deposition.
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Simpson, Matthew. "An analysis of unconfined ground water flow characteristics near a seepage-face boundary." University of Western Australia. Centre for Water Research, 2003. http://theses.library.uwa.edu.au/adt-WU2004.0025.
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A quantitative understanding of ground water flow characteristics in unconfined aquifers is important because of the prevalence of abstraction from, and pollution of these systems. The current understanding of ground water flow in unconfined aquifers is limited because of the dominance of horizontal flow modelling strategies used to represent unconfined flow processes. The application of horizontal flow principles leads to an ignorance of seepage-face formation and can not predict the complicated three-dimensional nature of the ground water flow that dominates at the ground water-surface water interface. This study aims to address some of these deficiencies by exploring the true three-dimensional nature of ground water flow including the formation of seepage faces at the ground water-surface water interface using numerical and laboratory techniques. A finite element model for simulating two-dimensional (vertical) variably saturated flow is developed and benchmarked against standard laboratory and field-scale solutions. The numerical features of the finite element model are explored and compared to a simple finite difference formulation. The comparison demonstrates how finite element formulations lead to a broader spatial averaging of material properties and a different method for the representation of specified flux boundaries. A detailed comparison analysis indicates that these differences in the finite element solution lead to an improved approximation to the partial differential equation governing two-dimensional (vertical) variably saturated flow. A laboratory analysis of unconfined ground water flow and associated solute transport characteristics was performed. The analysis focused upon unconfined flow towards a pumping well. The laboratory observations were reliably reproduced using a three-dimensional (axi-symmetric), variably saturated ground water flow model. The model was benchmarked against the ground water flow characteristics such as the seepage-face height and total flow rate. In addition, the model was shown to reliably reproduce the solute transport features such as travel times and streamline distributions. This is the first time that a numerical model has been used to reliably reproduce the solute transport characteristics near a seepage-face boundary where the three-dimensional flow effects are prevalent. The ability to reliably predict solute transport patterns in the seepage-face zone is important since this region is known to support vital microbially facilitated reactions that control nutrient cycling and contaminant attenuation. The three-dimensional travel time distribution near the seepage-face was compared to that predicted using a horizontal flow modelling approach derived from the basic Dupuit-Forchheimer equations. The Dupuit-Forchheimer based model indicated that horizontal flow modelling would under-estimate the total residence time near a seepage-face boundary, thereby introducing a considerable source of error in a solute transport analysis. For this analysis, a new analytical solution for the steady travel time distribution in an unconfined aquifer subject to a single pumping well was derived. The analytical model has identified, for the first time in the hydrogeology literature, the use of the imaginary error function. The imaginary error function is a standard transcendental function and an infinite series approach to evaluate the function was successfully proposed. The two-dimensional (vertical) ground water flow model was extended to handle the case where the flow is driven by density gradients near the ground water-surface water interface. The unsteady, two-dimensional, Galerkin finite element model of density-dependent ground water flow in variably saturated porous media is rigorously presented and partially benchmarked under fully saturated (confined) conditions. The partial benchmarking involved reproducing solutions to the standard Henry salt-water intrusion and the Elder salt-convection problems. The model was used in a standard density-coupled and a new density-uncoupled mode to elucidate the worthiness of the Henry and Elder problems as benchmark standards. A comparison of the coupled and uncoupled solutions indicates that the Henry salt-water intrusion problem has limited worthiness as a benchmark as the patterns of ground water flow are relatively insensitive to density-coupled effects. Alternatively, the Elder problem is completely dependent upon a correct representation of the density-coupled flow and solute transport processes. The coupled versus uncoupled comparison is proposed as a new test of the worthiness of benchmark standards. The Henry salt-water intrusion problem was further analysed in an attempt to alleviate some of the difficulties associated with this benchmark problem. The numerical model was tested against a re-evaluated version of Henry's semi-analytical solution for the coupled solute concentration distribution. The numerical model was used to propose a modified version of the Henry problem where the importance of density-coupled processes was increased. The modified problem was shown to have an improved worthiness as compared to the standard solution. The numerical model results were benchmarked against a new set of semi-analytical results for the modified problem. Certain advantages in using the modified problem as a test case for benchmarking the results of a numerical model of density-dependent ground water flow are identified. A numerical investigation of the patterns of density-driven ground water flow at the ground water-surface water interface was undertaken. The numerical model is shown to produce grid-independent results for a finely discretised domain. The pattern of discharge is controlled, in part, by two parameters. One describes the recharge applied to the aquifer, and the second describes the magnitude of the density differences between the fresh recharging fluid and the saline receiving fluid. The influence of dense intrusions upon the formation of seepage-face boundaries at the ground water-surface water interface under steady-state conditions was also investigated. Dense intrusions are shown to dominate the pattern of ground water flow only under mild recharge conditions, while seepage faces dominate the outflow pattern under strong recharge conditions. Therefore, the formation of seepage-face boundaries and dense intrusions are unlikely to coincide under the conditions examined in this study.
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Asadishad, Bahareh. "Transport and survival of bacteria in model aquatic environments: role of water chemistry, surface geochemistry, and temperature." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=121366.
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The occurrence of microbial pathogens in drinking water sources is recognized as a significant threat to public health. A better understanding of the key processes governing the fate of microbial pathogens in groundwater aquifers can help mitigate the risk of drinking water contamination. The attachment of pathogens to aquifer surfaces and the inactivation of attached and suspended pathogens are key processes that attenuate the concentration of viable pathogens in potable water supplies. Although substantial research effort has been aimed at elucidating the role of various physical, chemical and biological factors on the inactivation rate of microbes suspended in the aqueous phase, our understanding of microbe inactivation when attached to grain surfaces is limited. Thus, the first objective of this work was to develop a fluorescence-based experimental technique for evaluating the inactivation kinetics of bacteria adhered onto a surface in an aqueous environment. The technique was sensitive enough to distinguish between the inactivation kinetics of different representative bacteria attached to either a negatively or a positively charged surface. The new method was then used to characterize bacterial inactivation kinetics when attached to environmentally relevant surface chemistries such as metal oxides over a broad range of groundwater chemistries. X-ray photoelectron spectroscopy (XPS) characterization of bacterial-surface bonding was used to interpret inactivation behavior. It was observed that attachment of cells to metal-oxide surfaces can lead to formation of covalent bonds, specifically O- and C-metal bonds, between the cell and the surface, resulting in reduced bacterial viability (i.e., cell membrane integrity). Surface and near-surface soils in cold climate regions experience low temperature and freeze-thaw (FT) conditions in the winter. Microorganisms that are of concern to groundwater quality may have the potential to survive low temperature and FT in the soil and aqueous environments. Although there is a large body of literature on the survival of pathogenic bacteria at different environmental conditions, little is known about their transport in groundwater environments in low temperatures and after FT. Thus, in the second part of the project, the effect of cold temperature and repeated FT on survival, survival strategies such as motility and biofilm formation, and virulence of selected Gram-negative and Gram-positive bacteria was investigated. The adhesion properties and transport of bacteria exposed to FT were studied using quartz crystal microbalance with dissipation monitoring (QCM-D) and water saturated sand-packed columns. The expression levels of different genes encoding synthesis of flagellin, extracellular matrix production, and virulence factors were measured using quantitative reverse transcription polymerase chain reaction (qRT-PCR). Our findings demonstrate that bacteria exhibited greater retention onto sand grains after exposure to FT. Moreover, bacteria tend to survive for longer periods of time and may become more virulent at low temperature in higher ionic strength waters thereby posing a potential threat to drinking water supplies.L'apparition d'agents pathogènes microbiens dans les sources d'eau potable est reconnu comme une menace importante pour la santé publique. Une meilleure compréhension des processus fondamentaux qui régissent le sort des pathogènes microbiens dans les aquifères d'eau souterraine peut contribuer à atténuer le risque de contamination de l'eau potable. L'attachement des agents pathogènes aux surfaces des nappes phréatiques et leur inactivation lorsqu'ils sont attachés et suspendus, sont les processus clés qui atténuent la concentration des pathogènes viables dans l'approvisionnement en eau potable. Bien qu'un effort substantiel de recherche ait été réalisé, visant à élucider le rôle de divers facteurs physiques, chimiques et biologiques sur le taux d'inactivation des microbes en suspension dans la phase aqueuse, notre compréhension de l'inactivation du microbe lorsqu'il est attaché à la surface des grains est limitée. Ainsi, le premier objectif de ce travail était de développer une technique expérimentale basée sur la fluorescence pour évaluer la cinétique d'inactivation de bactéries collées sur une surface dans un environnement aqueux. La technique est suffisamment sensible pour faire la distinction entre la cinétique d'inactivation de différentes bactéries représentatives, montées soit sur une surface chargée négativement ou positivement. La nouvelle méthode a ensuite été utilisée pour caractériser la cinétique d'inactivation bactérienne lorsqu'elle est reliée à la chimie de surface environnementale telle que les oxydes métalliques et ceci sur une large gamme de produits chimiques des eaux souterraines. La caractérisation de la liaison bactérienne de surface par spectroscopie photoélectronique X (XPS) a été utilisée pour interpréter le comportement de l'inactivation. Il a été observé que l'attachement des cellules aux surfaces métal-oxyde peut conduire à la formation de liaisons covalentes, plus précisément des liaisons O- et C-métal, entre la cellule et la surface, ce qui entraîne une réduction de la viabilité bactérienne (i.e. une perte de l'intégrité de la membrane cellulaire).Dans les régions à climat froid, les sols de surface ou proches de la surface subissent de basses températures et des périodes de gel-dégel (GD). Les micro-organismes qui sont des sources de préoccupation pour la qualité des eaux souterraines peuvent avoir le potentiel de survivre à basses températures et aux périodes de GD, dans le sol et les milieux aqueux. Bien qu'il existe une littérature abondante sur la survie des bactéries pathogènes à différentes conditions environnementales, on possède peu d'informations au sujet de leur transport dans les environnements d'eau souterraine à des températures basses et après GD. Ainsi, dans la deuxième partie du projet, l'effet de la température froide et l'effet des périodes GD répétés ont été étudiés sur les stratégies de survie telles que la mobilité et la formation de biofilms ainsi que la virulence des bactéries sélectionnées à Gram négatif et Gram positif . Les propriétés d'adhérence et le transport des bactéries exposées à des périodes de GD ont été étudiés à l'aide d'une microbalance à cristal de quartz avec mesure de la dissipation (QCM-D) et de l'eau contenue dans des colonnes saturées de sable. Les niveaux d'expression des différents gènes codant pour la synthèse de la flagelline, la production de la matrice extracellulaire et des facteurs de virulence ont été mesurés en utilisant la transcription par réaction en chaîne par polymérase inverse quantitative (qRT-PCR). Nos résultats démontrent que les bactéries présentent une plus grande rétention sur les grains de sable après l'exposition aux périodes de GD. En outre, les bactéries ont tendance à survivre pendant de longues périodes de temps et peuvent devenir plus virulent à basse température dans des eaux à plus grande force ionique posant ainsi une menace potentielle pour l'eau potable.
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Kazour, Maria. "Active and passive biomonitoring tools for microplastics assessment in two highly polluted aquatic environments : case study of the Seine estuary and the Lebanese coast SOURCES OF MICROPLASTICS POLLUTION IN THE MARINE ENVIRONMENT: IMPORTANCE OF WASTEWATER TREATMENT PLANT AND COASTAL LANDFILL MICROPLASTICS POLLUTION ALONG THE LEBANESE COAST (EASTERN MEDITERRANEAN BASIN): OCCURRENCE IN SURFACE WATER, SEDIMENTS AND BIOTA SAMPLES JUVENILE FISH CAGING AS A TOOL FOR ASSESSING MICROPLASTICS CONTAMINATION IN ESTUARINE FISH NURSERY GROUNDS IS BLUE MUSSEL CAGING AN EFFICIENT METHOD FOR MONITORING ENVIRONMENTAL MICROPLASTICS POLLUTION?" Thesis, Littoral, 2019. http://www.theses.fr/2019DUNK0544.
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La production de plastique est en augmentation continue pour répondre à la forte demande mondiale. Cette production massive est la source d'importantes quantités de plastiques que l'on retrouve dans les milieux aquatiques. Parmi ces plastiques, les microplastiques (MP) (particules microscopiques d’une taille < 5 mm) se retrouvent dans l’eau, les sédiments et sont susceptibles d’être ingérés par divers organismes marins. Cette thèse se focalise sur (1) l’évaluation des sources et des apports de microplastiques au milieu aquatique et de leur présence dans les organismes, et (2) de tester la faisabilité d’utiliser des organismes vivants pour la surveillance de la pollution de l’environnement par les microplastiques. Deux zones côtières affectées par des pressions anthropogéniques ont été étudiées : Le Havre et le littoral libanais. Dans le premier cas, le rôle d’une station de traitement des eaux usées (STEP) et d’une décharge côtière dans l’introduction des microplastiques dans l’environnement a été étudié. Les MPs ont d’abord été analysés dans l'influent, la boue et l’effluent de la STEP. Leur devenir a été suivi selon un gradient de distance de la STEP au niveau de trois matrices : eau de surface, sédiments et moules sauvages (Mytilus spp.). Les MPs ont été trouvés au niveau de toutes les matrices avec une concentration qui diminue en s’éloignant de l’effluent. Des taux de microplastiques élevés (plus élevés que ceux trouvés à côté de la STEP) ont été observés à proximité de la décharge côtière, suggérant son rôle important comme voie d’entrée des MPs dans les eaux côtières. Le long de la côte libanaise, nous avons évalué pour la première fois la pollution par les MPs dans l'eau de mer, les sédiments et dans deux espèces marines importantes en terme de consommation humaine (un poisson pélagique: Engraulis encrasicolus et un bivalve: Spondylus spinosus). Les résultats ont montré différents patterns de concentration des MPs dans les matrices analysées. La présence de MPs dans les organismes était élevée (83.4% et 86.3% dans les anchois et les huîtres, respectivement). Ces résultats ont mis en évidence la pollution élevée liée aux MPs au niveau du bassin Levantin par rapport aux autres régions de la Méditerranée occidentale. De plus, les résultats obtenus indiquent une contribution potentielle des décharges côtières à cette pollution. Le plus souvent, les études sur les microplastiques impliquent l'échantillonnage d’organismes indigènes. Au cours de cette thèse, nous avons testé la faisabilité d'utiliser des organismes transplantés (encagement) pour évaluer la pollution par les microplastiques dans l'environnement marin côtier. Nous avons mis au point des expériences d'encagement avec des juvéniles de flets, Platichthys flesus, en estuaires et des moules bleues, Mytilus edulis, en zone côtière. Pour chaque espèce, l'abondance et les caractéristiques (forme, taille, couleur et type de polymères) des MPs ingérés par les individus encagés ont été comparées avec les MPs ingérés par des individus sauvages capturés sur le même site et avec ceux trouvés dans leur environnement (eaux de surface et sédiments). Nos résultats suggèrent que la technique d'encagement d'organismes peut constituer un outil prometteur pour la biosurveillance des MPs la rendant plus fiable et permettant une étude précise des effets biologiques des MPs sur une période d'exposition prédéterminéePlastic fabrication is increasing worldwide in response to daily human demands. This mass production is linked to the immense plastic marine litter found all around the world: each synthetic material is meant to find its way back into the aquatic systems. Anthropogenic pressure and the immense human population, the lack of appropriate plastic treatment process and the growing industrial activities advocate their presence in the aquatic environments. These plastics are then found in the form of microplastics (microscopic particle with a size < 5 mm) observed in the water, in the sediments and are prone to be ingested by various marine organisms along the trophic chain. This thesis focuses on (1) assessing microplastics sources and input into the aquatic environment and their occurrence in biota, and (2) to test the feasibility of using transplanted organisms (caging) for monitoring microplastics pollution in the marine coastal environment. Two coastal areas highly impacted by anthropogenic pressures were studied: Le Havre in France and the Lebanese coast. For the former, the role of a municipal wastewater treatment plant (WWTP) effluent and an abandoned coastal landfill as pathways for microplastics (MPs) input into the marine environment was assessed. MPs were first analyzed in raw sewage influent, sludge and effluent samples, and their fate was studied along a distance gradient from the WWTP in three matrices: surface water, sediments and wild mussels (Mytilus spp). MPs were found in all matrices with a decreasing abundance from the effluent. Strong MPs abundances (higher than those found near the WWTP effluent) were observed in the vicinity of the coastal landfill suggesting its importance as a MPs entry route into the marine coastal environment. Whereas for the Lebanese coast, we evaluated for the first time the MPs pollution in the seawater, sediments and two important seafood species (one pelagic fish: Engraulis encrasicolus and one bivalve: Spondylus spinosus). Results showed different patterns of MPs concentration in the analyzed matrices. The occurrence of MPs in the biota was high (83.4% and 86.3% in anchovies and spiny oysters, respectively). These results highlighted the high MPs pollution found in the Levantine Basin in comparison to other Western Mediterranean regions. In addition, the obtained results indicate the potential contribution of coastal landfills to this pollution. Most often microplastics studies involve collection of organisms’ samples from natural populations. In this thesis, we tested the feasibility of using transplanted organisms (caging) for monitoring microplastics’ pollution in the marine coastal environment. We developed caging experiments with juvenile European Flounder, Platichthys flesus, in estuarine nursery grounds and blue mussels, Mytilus edulis, in coastal marine environment. For each species, the abundance and characteristics (shape, size, color and type of polymers) of MPs ingested by caged individuals are compared with those ingested by wild individuals collected at the same site and with those found in their surrounding environment (surface water and sediments). Our results suggest that transplanted organisms (caging) may be a promising tool for MPs biomonitoring making monitoring more reliable with an accurate assessment of the biological effects of MPs over a predetermined exposure period
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Shreya, Shivangi. "Water Quality Protection - A Comparative Study of India and Sweden." Thesis, KTH, Mark- och vattenteknik (flyttat 20130630), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-210926.
Full textAbstract:
This report is a comparative study of ground water and surface water quality protection of a developing country India and a developed country Sweden. It covers the basic water policies, laws, rules, regulations and human right to water provisions in both the countries. The main aim of this report is to compare water quality approaches in India and Sweden and find out the best possible practices in each country and assess the need & feasibility of their application in the other. It describes the present water laws in both the countries and discusses about the present scenario of ground water and surface water quality, problems in ground water and surface water and how to deal with the problems in an efficient and sustainable way. It includes role of EU Water Framework Directive (EU WFD) in water quality protection in Sweden. Some interviews with stakeholders who are working in the water sector in Sweden are also included here. The main focus of this report is to analyse comparatively the present situation of water quality protection approaches and make recommendation for improvement of water quality. It focuses on “What can a developing country like India can learn from a developed country like Sweden for water quality protection?” and “Which things Sweden can adopt from India for water quality protection?” In this study India is found in worse environmental condition than Sweden. Indian ground water and surface water is more polluted than Swedish surface and ground water. Sweden is in much better condition than India and this country has more environmental concern too. In India, the basic reason for deterioration of water quality is lack of environment friendly attitude among the public, religious activities in water, corruption, loss of traditional methods of water conservation and protection, useless and unnecessary westernisation etc. In Sweden the basic cause of water quality deterioration is eutrophication in lakes, climate change, morphological changes, presence of metals and connectivity changes due to construction works, acidification etc. Sweden is an advanced country having the foresight for environmental concerns. They are doing research for betterment of water quality. India can learn some technological advancement and proper implementation of community participation in order to establish decentralised wastewater treatment plants and beneficial production and monitoring of energy resources from wastewater. Maintenance of online database for water is also a good thing to learn from Sweden.