Rozprawy doktorskie: „Pond water”

1

Shpiner, R. A. M. "Treatment of produced water by waste stabilsation pond". Thesis, Imperial College London, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.498655.

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Falabi, Ablawa Jeanne. "Pathogen removal from wastewater by a duckweed pond". Thesis, The University of Arizona, 1996. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_etd_hy0093_sip1_w.pdf&type=application/pdf.

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3

Saqqar, Muwaffaq M. "System analysis of a wastewater stabilization pond complex". Thesis, University of Newcastle Upon Tyne, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308964.

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Chmilar, Jennifer Andrea. "Ancient Maya Water Management: Archaeological Investigations at Turtle Pond, Northwestern Belize". Cincinnati, Ohio : University of Cincinnati, 2005. http://www.ohiolink.edu/etd/view.cgi?acc%5Fnum=ucin1121358311.

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5

Betts, Anthony Thomas. "Assessment of a Countywide Stormwater Pond Improvement Project: Impacts of the Hillsborough County Adopt-A-Pond Program". Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3009.

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Comparative research was conducted to assess the environmental impacts of the Adopt-a-Pond program, which operates throughout Hillsborough County, Florida. The Adopt-a-Pond program was established in 1992 and designed to address nonpoint pollution through outreach and stormwater pond enhancement. However, the program had never been thoroughly and scientifically evaluated. Therefore, assessments of water quality and vegetative characteristics were made at ninety Adopt-a-Pond participants and eleven control ponds to explore the potential impacts of the program on measurable environmental parameters. Statistical analysis of the results failed to demonstrate any statistically significant environmental improvements associated with the Adopt-a-Pond program, and measures of program activity did not illustrate a consistently positive relationship. These results indicate a need to readdress the policies and implementation of the program. Poor compliance by program volunteers, evident by the limited span of group participation (mean = 2.5 years) and relatively low percentage of actively involved residents, is the most likely culprit for the unremarkable improvements in pond quality, as pond enhancement techniques are firmly established in the literature. Overall, these conclusions underline the need for an integrated evaluation component in policymaking and an adaptive management approach to environmental management. A more detailed analysis is warranted to provide time series data, which examines ponds both before and after entry to the program and after implementing landmark improvement measures. In the end, the results of the study have provided a better understanding of the AAP and other similar restoration programs, and hopes to allow for enhancement of AAP program restoration practices.

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6

Westensee, Dirk Karl. "Post-treatment technologies for integrated algal pond systems". Thesis, Rhodes University, 2015. http://hdl.handle.net/10962/d1018180.

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Integrated Algae Pond Systems (IAPS) are a derivation of the Oswald designed Algal Integrated Wastewater Pond Systems (AIWPS®) and combine the use of anaerobic and aerobic bioprocesses to effect wastewater treatment. IAPS technology was introduced to South Africa in 1996 and a pilot plant designed and commissioned at the Belmont Valley WWTW in Grahamstown. The system has been in continual use since implementation and affords a secondarily treated water for reclamation according to its design specifications which most closely resemble those of the AIWPS® Advanced Secondary Process developed by Oswald. As a consequence, and as might be expected, while the technology performed well and delivered a final effluent superior to most pond systems deployed in South Africa it was unable to meet The Department of Water Affairs General Standard for nutrient removal and effluent discharge. The work described in this thesis involved the design, construction, and evaluation of several tertiary treatment units (TTU') for incorporation into the IAPS process design. Included were; Maturation Ponds (MP), Slow Sand Filter (SSF) and Rock Filters (RF). Three MP's were constructed in series with a 12 day retention time and operated in parallel with a two-layered SSF and a three-stage RF. Water quality of the effluent emerging from each of these TTU's was monitored over a 10 month period. Significant decreases in the chemical oxygen demand (COD), ammonium-N, phosphate-P, nitrate-N, faecal coliforms (FC) and total coliforms (TC) were achieved by these TTU's. On average, throughout the testing period, water quality was within the statutory limit for discharge to a water course that is not a listed water course, with the exception of the total suspended solids (TSS). The RF was determined as the most suitable TTU for commercial use due to production of a better quality water, smaller footprint, lower construction costs and less maintenance required. From the results of this investigation it is concluded that commercial deployment of IAPS for the treatment of municipal sewage requires the inclusion of a suitable TTU. Furthermore, and based on the findings presented, RF appears most appropriate to ensure that quality of the final effluent meets the standard for discharge.

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Desrochers, Anne. "Water harvesting through ponds in the Arco Seco region of the Republic of Panama : decision support system for pond storage capacity estimation". Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80908.

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The 'Arco Seco' or 'Dry Arc' region of the Republic of Panama is considered to be the driest in the country, where many areas of this region experience severe water stress during the months of January through May. This study was conducted to develop a tool for the assessment of sustainable implementation of water harvesting through ponds for agricultural purposes in the region. A computer based Decision Support System (DSS) has been developed specifically for the Arco Seco region in order to facilitate pond storage capacity estimation. As part of the DSS, four computer programs have been designed for four different case scenarios; the first one is for sites that have high water demand and no topographical restrictions for pond size; the second is for fairly high water demand, no topographical restrictions for pond size, and for farmers who wish to have a backup of water to use mostly during drier years; the third is for low water demand, usage during the dry season only, and topographical restrictions for pond size, and finally the fourth is for constant water demand throughout the year, and for sites where runoff is the only water source.*
*This dissertation is a compound document (contains both a paper copy and a CD as part of the dissertation).

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8

Schneider, Seth J. "Hydrothermal and water quality modelng for evaluation of Ashumet Pond trophic state". Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/42637.

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Thye, F. Brian. "Virginia Tech Duck Pond Retrofit for Improved Water Quality in Stroubles Creek". Master's thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/46523.

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Stroubles Creek is registered on Virginiaâ s 303(d) list of impaired waters for both benthic and fecal coliform impairments. The upper reach of the creekâ s watershed drains into two ponds on the Virginia Tech campus. The area draining to the ponds, approximately 715 acres, encompasses most of the Town of Blacksburg and the Virginia Tech campus. Below the ponds, the creekâ s watershed is primarily forested and agricultural, with some areas of residential development. In order to improve water quality downstream, the two ponds will be converted to a water quality facility by redirecting all flow from the northern branch of Stroubles Creek into the upper, smaller pond, which then flows into the larger pond below. With flow into the upper pond increasing dramatically, the dam between the two ponds and associated overflow structures were evaluated and redesigned to protect the dam from overtopping and possible washout. In addition, concrete weirs were designed and will be constructed on both branches of Stroubles Creek above the ponds for future installation of flow and water quality monitoring equipment. Above the ponds, the banks along both branches of the creek have become severely eroded. Interlocking concrete block armoring was designed for the stream banks to reduce erosion and protect the trees growing along the creek. This project was jointly funded by Virginia Tech and a grant from the Virginia Department of Conservation and Recreation Water Quality Improvement Fund. Construction will be performed by the Capital Design department of Virginia Tech.
Master of Science

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10

MCCORKEL, MIA, Chandra Khatri, Ritika Mohan i Elizabeth Pedersen. "TREATMENT OF CENTRAL ARIZONA PROJECT WATER: REVERSE OSMOSIS AND EVAPORATION POND BRINE DISPOSAL". Thesis, The University of Arizona, 2009. http://hdl.handle.net/10150/192552.

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Bowen, Christian A. "Effects of Raceway Pond Water and Nutrient Recycling on Microalgae Production and Harvesting". DigitalCommons@CalPoly, 2018. https://digitalcommons.calpoly.edu/theses/1896.

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To be environmentally sustainable, algae biofuel production requires extensive recycling of water and nutrients during algae cultivation. Such recycling can be in the form of reuse of external wastewaters, such as from municipal sewers, but, to achieve significant biofuels production, internal recycling at the algae farms is also needed. A potential difficulty with internal recycling is the accumulation of auto-inhibitory compounds in recycled algae pond water. An additional concern is that nutrients in the residuals from algae biofuel manufacturing will be only partly bioavailable. Both these factors can limit the extent of internal recycling. Ultimately, combining external and internal recycling might be the most sustainable as long as these limiting factors are not excessive. Another important consideration in algae biofuel feedstock production is harvesting, which can be energy intensive and expensive. Bioflocculation of algae cells followed by sedimentation is a low input harvesting method, but one that might be affected by resource recycling. In the present 7-month study, algae productivity and settleability were measured for several types of water and nutrient recycling, using pilot raceways and tubes settler tanks fed municipal wastewater. Two control raceway sets and two types of water and nutrient recycling raceway sets were operated concurrently. Each set was comprised of duplicate raceways (33-m2 surface area each, 0.3-m deep, 4-day hydraulic residence time with CO2 supplementation). One control set was fed primary clarifier effluent while the other control set was fed nitrified, filtered reclaimed wastewater. The two experimental raceway sets were fed different nutrients. One set received anaerobically-digested algal biomass (algae digestate) and the other set chemical fertilizer. Both recycling raceway sets were monitored to determine if water and nutrient recycling had any detrimental impacts on algal biomass growth. Productivity was reported as gross and net in terms of volatile suspended solids (VSS). Gross productivity was based on raceway effluent biomass flow, which could be harvested for biofuel production. Net productivity was based on influent minus effluent biomass flows, which better represents algae growth. As a complement to the productivity data, measurements were made of indictors (salt, soluble chemical oxygen demand, and soluble UV absorbance) of potentially inhibitory substances and of nitrogen and phosphorus concentrations, which would have limited growth if they were too low. After 7 months of continuous operation and 50 cycles of water reuse, the algae productivities of the water and nutrient recycling raceways matched or exceeded the productivities of the control raceways. Net productivities of the primary effluent-fed and reclaimed water-fed control ponds averaged 15.4 and 18.0 g-VSS/m2-day, respectively, while the digestate-fed and fertilizer-fed recycling ponds net productivities averaged 19.6 and 18.8 g-VSS/m2-day, respectively. The average standard deviation of the various duplicate sets ranged from 0.3 – 4.0 g-VSS/m2-day. These results do not indicate that algae were inhibited during the 7 months of continuous water recycling and digestate fertilization. In fact, the results suggest that recycling enhances productivity, although the statistical power of this experiment was low. Indicators of potentially inhibitory substances were monitored during the experiment (salinity, soluble chemical oxygen demand, and UV absorbance). Only salt concentrations showed significant accumulation in the ponds, but not to concentrations expected to be inhibitory. A greater number of replicates and a longer experimental period are recommended in future experiments.

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12

Jimoh, Taobat Adekilekun. "Water quality, biomass and extracellular polymeric substances in an integrated algae pond system". Thesis, Rhodes University, 2018. http://hdl.handle.net/10962/57307.

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Integrated algae pond systems (IAPS) combine the use of anaerobic and aerobic bioprocesses to effect wastewater treatment. Although, IAPS as a technology process offers many advantages including efficient and simultaneous N and P removal, no requirement for additional chemicals, O2 generation, CO2 mitigation, and a biomass with potential for valorization, a lack of technological advancement and the need for large land area, has limited the reach of this technology at industrial scale. In mitigation, peroxonation was introduced as a tertiary treatment unit and its effect on COD and TSS of IAPS treated water investigated. An effort was made to characterize the soluble but persistent COD in IAPS treated water and, productivity of the HRAOP mixed liquor was investigated to gain insight into the potential use of this biomass. Results show that peroxone treatment effectively reduced COD, TSS, and nutrient load of IAPS water without any significant impact on land area requirement. Indeed, summary data describing the effect of peroxone on quality of IAPS-treated water confirmed that it complies with the general limit values for either irrigation or discharge into a water resource that is not a listed water resource for volumes up to 2 ML of treated wastewater on any given day. Extraction followed by FT-IR spectroscopy was used to confirm albeit tentatively, the identity of the soluble but persistent COD in IAPS treated water as MaB-floc EPS. Results show that MaB-flocs from HRAOPs are assemblages of microorganisms produced as discrete aggregates as a result of microbial EPS production. A relationship between photosynthesis and EPS production was established by quantification of the EPS following exposure of MaB-flocs to either continuous light or darkness. Several novel strains of bacteria were isolated from HRAOP mixed liquor and 16S ribosomal genomic sequence analysis resulted in the molecular characterization of Planococcus maitriensis strain ECCN 45b. This is the first report of Planococcus maitriensis from a wastewater treatment process. Productivity and change in MaB-flocs concentration, measured as mixed liquor suspended solids (MLSS) between morning and evening were monitored and revealed that MLSS is composed of microalgae and bacteria but not fungi. Concentration varied from 77 mg L-1 in September (winter) to 285 mg L-1 in November (spring); pond productivity increased from 5.8 g m-2 d-1 (winter) to 21.5 g m-2 d-1 (spring); and, irrespective of MLSS concentration in late afternoon, approximately 39% was lost overnight, which presumably occurred due to passive removal by the algae settling pond. The outcomes of this research are discussed in terms of the quality of treated water, and the further development of IAPS as a platform technology for establishing a biorefinery within the wastewater treatment sector.

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13

Hounkpe, Wendeou Sèna Peace. "Wastewater treatment and resource recovery for poverty alleviation : a combined duckweed and water hyacinth pond system". Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/20965.

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Floating macrophyte pond systems, with the ability to produce nutrient enriched plants simultaneously with wastewater treatment, are a sustainable solution to contribute to environmental protection and safe nutrient recovery from domestic wastewater. However, to meet the requirements for reuse with high strength wastewater containing high levels of metal pollution generated in developing countries, an adequate combination of water hyacinth and duckweed ponds is proposed in order to take advantage of the best characteristics of each of these macrophyte ponds. This research focused on the advancing of the understanding of the effectiveness of treatment and resource recovery under the effect of changing operational parameters such as pH, light intensity, influent metal content and fluctuating pollutants loading rate on pond performance and recycling ability in order to fill the noticed gap of knowledge. Experiments conducted in water hyacinth ponds (WHP), under batch and tropical natural weather conditions, revealed that pH between 6.4 and 7.1, full sunlight and seven days hydraulic retention time were optimum for plant biomass production and pollutant removal in WHP. WHP was able to regulate pH when the initial pH values moved outside this interval with a drop in biomass production as a side effect. These ponds showed a first order kinetic for the removal of iron, zinc and copper from aqueous solution and their accumulation in plants biomass with a preferential sequence Fe > Zn > Cu. However the presence of metals in water hyacinth biomass led to the reduction in ponds performances and a risk of re-pollution of the effluent through the release of metals into water. A comparative study carried out over sixty-two weeks in a pilot scale combined water hyacinth and duckweed ponds (DWP) channel and waste stabilization ponds channel working under fluctuating loading rates showed different environmental conditions occurred these ponds. The fluctuating loading rate was also found to have a reduced effect on the combined WHP/DWP channel performance and effluent quality stability with the effluents meeting the entire reuse requirement at high hydraulic flow rate (retention time greater than 20 days). Fish was able to grow in the WHP/DWP channel. Results suggested some guidelines on WHP/DWP system design, operation and maintenance. The overall outcome of this research is a significant contribution to the development of integrated combined WHP/DWP technology for treatment of wastewater and resource recovery on site.

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14

Prokešová, Eva. "Posouzení možnosti zřízení vodní nádrže". Master's thesis, Vysoké učení technické v Brně. Ústav soudního inženýrství, 2019. http://www.nusl.cz/ntk/nusl-402596.

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The aim of the thesis is to assess the possibility of establishing a water reservoir in s selected location witch regard to its possible water management activities including geological conditions. The thesis also defines basic terms related to water reservoir and their parts. This work was elaborated with the help of available literature and valid laws of the Czech Republic concerning the given issue. At the end of the work will be valued land meeting the conditions for the construction of a small water tank. The award will take place in two ways according to the decree and direct comparison.

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15

Vickers, Shannon Lynne. "Metal mobility in a stormwater detention pond, investigating metal mobility and sediment-water exchange". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0002/MQ46012.pdf.

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16

Choi, Julia. "The study of biological interactions using water quality modeling : Massachusetts Military Reservation, Ashumet Pond". Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/42623.

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Chainark, Suwanit Boyd Claude E. "Effect of sodium nitrate treatment on water and sediment quality in laboratory and pond studies". Auburn, Ala, 2008. http://hdl.handle.net/10415/1454.

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Ouedraogo, Faissal Romaric. "Impact of Sludge Layer Geometry on the Hydraulic Performance of a Waste Stabilization Pond". Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6344.

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Improving the hydraulic performance of waste stabilization ponds (WSPs) is an important management strategy to not only ensure protection of public health and the environment, but also to maximize the potential reuse of valuable resources found in the treated effluent. To reuse effluent from WSPs, a better understanding of the factors that impact the hydraulic performance of the system is needed. One major factor determining the hydraulic performance of a WSP is sludge accumulation, which alters the volume of the pond. In this study, computational fluid dynamics (CFD) analysis was applied to investigate the impact of sludge layer geometry on hydraulic performance of a facultative pond, typically used in many small communities throughout the developing world. Four waste stabilization pond cases with different sludge volumes and distributions were investigated. Results indicate that sludge distribution and volume have a significant impact on wastewater treatment efficiency and capacity. Although treatment capacity is reduced with accumulation of sludge, the latter may induce a baffling effect which causes the flow to behave closer to that of plug flow reactor and thus increase treatment efficiency. In addition to sludge accumulation and distribution, the impact of water surface level is also investigated through two additional cases. Findings show that an increase in water level while keeping a constant flow rate can result in a significant decrease in the hydraulic performance by reducing the sludge baffling effect, suggesting a careful monitoring of sludge accumulation and water surface level in WSP systems.

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Vemuri, Sruthi Chowdary. "Nutrient Removal in a Constructed Wetland, and Impact on Water Quality in a Downstream Pond". Youngstown State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1327337303.

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20

Murphy, Sarah Elizabeth. "An investigation into the treatment efficiency of a primary pond in the Barker Inlet Stormwater Wetland System, South Australia /". Title page, table of contents and abstract only, 1999. http://web4.library.adelaide.edu.au/theses/09ENS/09ensm978.pdf.

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Thesis (M.Eng.Sc.)--University of Adelaide, Dept. of Civil and Environmental Engineering, 2000?
Corrigenda pasted onto front end-paper. The CD contains Excel spreadsheets containing data collected. Bibliography: leaves 209-222.

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21

Lizima, Louis. "Hydraulic Evaluation of a Community Managed Wastewater Stabilization Pond System in Bolivia". Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4360.

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This work explores the hydraulic performance of a wastewater lagoon system located in San Antonio, Bolivia. The system consists of one facultative pond and two maturation ponds in series and is managed through a locally elected water committee. A tracer study was performed on the primary facultative pond and an analysis of the solids accumulation on the bottom of the facultative lagoon was also performed. The results were used to generate residence time distribution curves and provide an estimate of mean residence time in the system. The data was used to examine hydraulic efficiency as it relates to short-circuiting and dead zones. A sludge study accumulation study was performed using the white towel method and the resulting measurements were interpolated to determine a total estimated sludge volume of 169 m3 (which is 8% of the facultative pond volume). An orange study was also performed to assess the surface flow pattern in the system. The results were compared with a computational 2-d model. The 2-d model incorporated the estimated sludge distribution and provided a good fit for the tracer dye concentrations measured in the field over the 12 day study period. Simple models such as the Tanks in Series and the Completely mixed model were evaluated and abandoned because of their inability to model the physical behavior in the system. The Completely mixed model did however perform better than the Plug flow model. After comparing the tracer results from the reactor models that were considered: Tanks in Series, Completely mixed fluid, manual interpolation and the results from the 2-d cfd flow simulation, the results that provided the best fit for the data over 12 days was the manual interpolation method at a flow rate of 98 m3/day and configuration D at 60 m3/day. However, because of uncertainty as to what depth to obtain a representative area for the 2-d simplification and sensitivity to flow; all four configurations were considered for estimating the MHRT at the lowest measured flow rate of 60 m3/day. The results at a flow rate of 60 m3/day varied between 10.88 and 13.04 days for the MHRT with a hydraulic efficiency that varied between 33-51.6% (accounting for sludge volume). This is much shorter than the actual nominal retention time of 37 days and the design nominal retention time of 26 days. As a result it was concluded that short-circuiting was occurring in the facultative lagoon.

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Harper, Elizabeth B. "The role of terrrestrial habitat in the population dynamics and conservation of pond-breeding amphibians". Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/4693.

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Thesis (Ph. D.)--University of Missouri-Columbia, 2007.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on September 25, 2007) Vita. Includes bibliographical references.

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Gornak, Steven. "A Comparison of Meristics and Morphometrics between Two Strains of Pond Cultured Striped Bass (Morone saxatilis)". W&M ScholarWorks, 1991. https://scholarworks.wm.edu/etd/1539617636.

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Ansah, Yaw Boamah. "Characterization of pond effluents and biological and physicochemical assessment of receiving waters in Ghana". Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/31948.

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This study was carried out to characterize ponds and aquaculture systems, and also to determine both the potential and actual impacts of pond aquaculture effluents on receiving stream quality in the Ashanti and Brong Ahafo regions of Ghana. Water, fish and macroinvertebrate samples were collected from upstream, downstream and nearby reference streams of, and questionnaires administered to, 32 farms. Total settleable solids were higher in ponds than reference streams (p = 0.0166); suspended solids was higher in ponds than reference streams (p = 0.0159) and upstream (p = 0.0361); and total phosphorus was higher in ponds than reference (p = 0.0274) and upstream (p = 0.0269). Total nitrogen was most clearly higher in ponds than all other locations: p = 0.0016, 0.0086 and 0.0154 for the differences between ponds and reference, upstream, and downstream respectively. BOD5 level was also higher in ponds than all locations (p = 0.0048, 0.0009, and 0.0012 respectively). Also, non-guarding fish species were more abundant in reference streams than downstream (p = 0.0214) and upstream (p = 0.0251), and sand-detritus spawning fish were less predominant in reference streams than upstream (p = 0.0222) and marginally less in downstream locations (p = 0.0539). A possible subsidy-stress response within study streams was also observed. Hence, ponds are potential sources of these water quality variables to receiving streams. Effluent-receiving streams, generally, were not much different from reference streams in terms of most the metrics of community structure and function used in the comparisons. Hence, even though receiving streams in Central Ghana may not be severely impacted by aquaculture effluents at the moment, the management of pond effluents will determine the scale of future impact. Vegetable, cereal, and livestock farming could serve as additional sources of fecal streptococci and coliform bacteria and nutrient-enrichment within the study area, besides aquaculture, and so these industries must also be included in efforts to minimize pollution of these streams.
Master of Science

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Lévesque, Céleste Marie. "Oil sands process water and tailings pond contaminant transport and fate : physical, chemical and biological processes". Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/50023.

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The Alberta Oil Sands development has been in operation since the 1960s, where innovations in technology in bitumen extraction have resulted in adaptive management of environmental sensitivities to Oil Sands Process-affected Water (OSPW) and tailings. This research assessed all the potential processes that OSPW constituents might undergo in the tailings impoundments in order to theorize on their ultimate fate. A conceptual tailing pond model was created, the first of its kind as there have been no attempts in the existing literature, and a tool for future management of these facilities. The development of a model is quite complex where the objectives are defined (e.g. OSPW constituents) and the various physical, chemical, biological, geochemical, hydrological and limnological processes involved. This research was conducted by one individual, while such integration and analysis would typically be tackled by a team of multidisciplinary experts. The scope of this research included the OSPW produced from oil sands open-pit mining, extraction and processing of bitumen. The crushing of ore and chemical additives affect water chemistry through the release of ions, salts, metals and organic compounds. Oil sands mines generate process affected water high in contaminants and the high degree of water recycling further concentrates these substances. The spatial and geological focus comprised the Athabasca ore deposit, with special attention on the Fort McMurray area and particular examination of the Mildred Lake Settling basin. A thorough literature review was conducted where the data and concepts from various scientific sources were utilized as a basis in the creation of a Tailings Pond Model, to conceptualize the physical, chemical and biological processes within a typical tailings settling basin. All further refinement and upgrading of the bitumen, processing of coke or other by-products were out of scope. Technological innovations in bitumen extraction and assisted tailings consolidation have resulted in more complex constituent compositions. The physical, chemical and biological processes occurring within a tailings pond are multifaceted making it difficult to model the ultimate fates of various substances. Chemical oxidation and bacterial decomposition have been shown to decrease toxicity of certain contaminants of greater concern.
Applied Science, Faculty of
Chemical and Biological Engineering, Department of
Graduate

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26

Caporuscio, Elizabeth. "EVALUATION OF A SEQUENTIAL POND SYSTEM FOR DETENTION AND TREATMENT OF RUNOFF AT SKYPARK, SANTA'S VILLAGE". CSUSB ScholarWorks, 2018. https://scholarworks.lib.csusb.edu/etd/773.

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Understanding the extent to which human activities impact surface water resources has become increasingly important as both human population growth and related landscape changes impact water quality and quantity across varying geographical scales. Skypark, Santa’s Village is a 233.76-acre tourism-based outdoor recreation area located in Skyforest, California residing within the San Bernardino National Forest. The park is situated at Hooks Creek, the headwaters of the Mojave River Watershed, and is characterized by a diverse landscape that includes forest cover and human development, including impervious surfaces, a restored meadow, and recreational trails. In 2016, Hencks Meadow was considered degraded by human activity and restored by the Natural Resources Conservation Services (NRCS) using best management practices (BMPs) to manage stormwater runoff and mitigate pollutants entering recreational downstream surface water. Three BMP detention basins were constructed to store and improve water quality from stormwater runoff. The purpose of this study is to observe the extent to which the engineered BMP detention basins design were effective in mitigating stormwater pollution from entering Hooks Creek. Over a six to eight month period (January to August), ponds were tested in situ bi-weekly for temperature (ºC), dissolved oxygen (mg/L), pH, turbidity (NTU), conductivity (µS/cm), nitrate (mg/L), and ammonium (mg/L), with additional laboratory tests for total suspended solids (mg/L), total dissolved solids (mg/L), chemical oxygen demand (mg/L), total coliform (MPN/100mL), Escherichia coli (MPN/100mL), and trace metals (µg/L). The results of this study support that the BMP design is improving surface stormwater runoff from impervious surfaces before it enters Hooks Creek. Findings could also promote the design and implementation of stormwater BMP detention basins at other site locations where water degradation is evident. Furthermore, this research can be used to promote the necessary improvement of water quality and quantity on a widespread geographical scale.

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Dang, Thien Ngon. "Autonomous water-cleaning machine using solar energy in shrimp ponds". Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-99264.

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Limited water exchange shrimp culture technology is commonly used today in many shrimp farms in Vietnam to reduce water usage, input of diseases and discharge of nutrient-rich effluents into environment as well as to increase the production per unit area. However, a remaining problem in this technology is that the water quality in shrimp ponds will be reduced due to limitation of water exchange for a long period. The accumulation of inorganic components such as waste feed, bacterial deposits or other biological debris at the pond bottom will lead to low dissolved oxygen, high ammonia-nitrogen level, high fecal coliform bacteria and high turbidity which cause a severe degradation of water quality and detriment to shrimp growth and survival. To solve this remaining problem, an autonomous water-cleaning machine for shrimp ponds was designed to control the waste accumulation in the pond. This is an effective solution to replace manual cleaning methods for water quality management in shrimp farming in the coastal area of the Mekong delta of Vietnam. Especially, this technique can be used for biosecure shrimp production systems according to GMP standards to meet the objectives for sustainable development of shrimp aquaculture in Vietnam
Kỹ thuật nuôi tôm không thay nước đang được sử dụng rộng rãi ở các trại nuôi tôm Việt Nam vì giúp giảm lượng nước sử dụng, hạn chế thải nước vào môi trường và giúp tăng diện tích nuôi trồng tôm. Tuy nhiên, bản thân kỹ thuật này cũng tạo nên một sản phẩm chất thải là phân tôm, thức ăn và chế phẩm sinh học xử lý nước dư thừa. Chất thải này dần dần tích tụ dưới đáy ao tạo thành lớp bùn độc, rất thiếu ôxy và chứa nhiều chất gây hại như ammonia, nitrite, hydrogen sulfide. Để tránh làm giảm diện tích ao nuôi do chất thải tích tụ làm tôm lảng tránh và tăng mật độ tôm nuôi trồng, thiết bị tự hành thu gom chất thải làm sạch nước trong vuông nuôi tôm đã được nghiên cứu, thiết kế và chế tạo thành công. Thiết bị đã thay thế các hoạt động làm sạch chất thải thủ công của con người, không sử dụng các nguồn năng lượng gây ô nhiễm, giảm nhu cầu về điện góp phần phát triển sản xuất tôm sạch đạt chuẩn GMP và phát triển bền vững ở các tỉnh ven biển miền Tây Việt Nam

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Xu, Bojun. "Microbial fuel cells coupled with open pond for wastewater treatment: is it viable?" Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/52987.

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Sediment microbial fuel cell (SMFC) is a special type of microbial fuel cells that can be deployed in a natural water body for energy production and contaminant removal. This MS project aims to explore whether it will be viable to apply SMFCs for wastewater treatment. Experimental SMFCs were studied in several configurations and operational modes for organic removal, nitrate reduction, and energy recovery. When treating an artificial secondary effluent for nitrate removal, the SMFC could remove 44% of the nitrate, higher than that without electricity generation. The enhanced removal was attributed to the supply of electrons to nitrate reduction in the aqueous phase through oxidizing the organics in the sediment. The lack of a proper separator between the anode and the cathode led to the failure of the SMFC when treating an artificial raw wastewater. Ion exchange membranes were incorporated into the MFCs that were installed in a lab-scale open water pond (150 L in volume). Such a system achieved 100% COD removal and more than 75% removal of ammonium nitrogen. However, denitrification remained as a challenge because of a lack of anoxic zone. To reduce the cost of the cathode catalysts, a polymer-based carbon cloth was investigated and exhibited better performance than bare carbon cloth. The results of this MS project have demonstrated that SMFCs in the absence of a proper separator cannot be applied for wastewater treatment. A membrane-based MFC system integrated with open pond may function as a wastewater treatment system, though nitrogen removal efficiency must be improved.
Master of Science

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29

Stoudt, Amanda. "Pollution Prevention and Water Reuse at Utah Department of Transportation Facilities". DigitalCommons@USU, 2020. https://digitalcommons.usu.edu/etd/7714.

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As stormwater flows over roads, sidewalks, and other impervious surfaces, it picks up pollutants that are deposited on these surfaces. One common pollutant transported by stormwater is road salt. While the application of road salt is crucial for wintertime public safety, road salt has a host of negative environmental impacts. Road salt has been linked to increasing levels of dissolved solids in groundwater, vegetation damage, and behavioral changes in aquatic organisms. Studies have shown that these impacts are concentrated around salt storage facilities. As a result, the United States Environmental Protection Agency issued many state departments of transportation municipal separate storm sewer system (MS4) permits. In Utah, road salt is stored at Utah Department of Transportation (UDOT) maintenance stations, which are regulated by a Phase I MS4 permit. To comply with their MS4 permit, UDOT constructed retention ponds to capture salt-laden stormwater and truck wash water. However, without information and established maintenance and management plans informing pond design, these retention ponds suffer from design issues such as overflow throughout the winter season. Through pollution prevention assessments, pond and tap water analysis, pond sediment analysis, and surface water quality modeling at 11 UDOT maintenance stations, this project provides UDOT with site design guidelines and best management practices to ultimately reduce the impact of UDOT road salt facilities on the environment.

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Bozkurt, Okan Cagri. "Operation Of The Water Control Structures". Master's thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615419/index.pdf.

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Floods are one of the most important natural disasters regarding damages caused by them. Major reasons of huge damages of floods are unplanned urbanization, narrowing of river beds and incorrect operation of water control structures. Geographic Information Systems (GIS) can provide important tools to be used in flood modeling studies. In this study, Lake Mogan, Lake Eymir and Incesu Detention Pond subbasins are studied for flooding events within GIS framework. These subbasins are important catchment areas of city of Ankara with total drainage area of 1070 km2. Soil Conservation Service (SCS) method is used to obtain flood hydrographs for 12 hour duration and 50, 100 and 500 year return periods. Flood routing procedure is applied to obtain discharges at the outlet of the Mogan and Eymir Lakes and Incesu Detention Pond. Operation performance of water control structures are tried to be estimated by using hydrographs which are obtained for different scenarios. Results show that elements of Lake Mogan Water Control Structure do not have capability to discharge 500 year storm safely to the downstream of the lake. However, 100 year storm can be routed without creating problem if necessary small precautions are taken. On the other hand, water control elements of Lake Eymir and Incesu Detention Pond can transmit obtained flood volumes to the downstream parts by assuming that closed conduit at the exit of Incesu Detention Pond can safely convey resultant flood discharges.

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TÃvora, Marcelo Aguiar. "Impact Socioenvironmental Release of Leachate and Sewage in Water Resources: The Case of Pond Borzeguim, Itapipoca-CE". Universidade Federal do CearÃ, 2010. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=9009.

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FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico
O municÃpio de Itapipoca localiza-se na zona norte da regiÃo do estado do CearÃ e dista 133 km da capital, Fortaleza. Sua populaÃÃo Ã estimada em 114 mil habitantes e a cidade enfrenta um problema ambiental comum a outras cidades cearenses: a destinaÃÃo dos resÃduos sÃlidos em lixÃes. O lixÃo do municÃpio de Itapipoca foi instalado em 2002 em Ãrea de grande vulnerabilidade socioambiental, nas proximidades de uma importante lagoa e de uma comunidade que dela se utiliza para atividades econÃmicas e consumo prÃprio. A comunidade do Borzeguim â nome homÃnimo ao da lagoa â possui cerca de 50 famÃlias que desde 2002 protestam contra a chegada do lixÃo. NÃo obstante, em 2004, foi instalada uma estaÃÃo de tratamento de esgoto com efluente sendo lanÃado no mesmo sistema hÃdrico impactado pelo lixÃo. Por nÃo existir um estudo dessa natureza na regiÃo com a finalidade de saber o real impacto causado, Ã que o presente trabalho foi desenvolvido. Dessa forma, o objetivo deste Ã analisar os impactos socioambientais decorrentes da disposiÃÃo inadequada de resÃduos sÃlidos e lÃquidos nos recursos hÃdricos da comunidade supracitada. Os objetivos especÃficos sÃo avaliar o impacto social da disposiÃÃo inadequada dos resÃduos sÃlidos sobre a populaÃÃo que reside no entorno do lixÃo; avaliar a qualidade das Ãguas do sistema hÃdrico em estudo, identificando os parÃmetros que excedam os limites estabelecidos pela resoluÃÃo CONAMA 357/2005; simular o comportamento da autodepuraÃÃo do trecho em estudo considerando-se o parÃmetro de oxigÃnio dissolvido. Para isso foram realizadas entrevistas semi-orientadas com uma amostra da comunidade e com os catadores encontrados no lixÃo com intuito de contemplar o diagnÃstico social. Para o diagnÃstico fÃsico-ambiental da qualidade de Ãgua superficial, foram realizadas quatro campanhas e analisados os seguintes parÃmetros: OD, DBO, pH, Coliformes Termotolerantes, E.Coli, Salinidade e TransparÃncia de Secchi. Foram simulados os comportamentos da autodepuraÃÃo do sistema hÃdrico em estudo utilizando-se da modelagem de qualidade de Ãgua proposta por Streeter & Phelps e a carga da DBO. Com isso, chegou-se Ãs seguintes conclusÃes: 1) o lixÃo e a ETE causam transtornos Ã comunidade do Borzeguim, exalam mau cheiro, desvalorizam a comunidade provocando sentimentos de racismo por parte de terceiros e depreciaÃÃo imobiliÃria, bem como modificam as relaÃÃes entre comunidade e lagoa. 2) o lixÃo causa forte depleÃÃo de OD no riacho enquanto que a ETE acelera a reaeraÃÃo do sistema; 3) a lagoa encontra-se eutrofizada, possui excessiva presenÃa de microalgas na superfÃcie, alta taxa de produtividade primÃria e diminuta zona fÃtica. 4) a carga poluente oriunda da cidade se mostrou importante fator da degradaÃÃo. Dessa forma, fica clara a importÃncia de estudos interdisciplinares acerca da questÃo dos resÃduos sÃlidos para que sirvam de subsÃdios a planos de recuperaÃÃo da Ãrea degradada e planos de gestÃo.
The municipality of Itapipoca is located in the northern region of the state of Ceara, some 133 km from the capital, Fortaleza. Its population is estimated at 114 000 inhabitants and the city faces an environmental problem common to other cities in CearÃ: the disposal of solid waste in landfills. The landfill site at Itapipoca was installed in 2002 in an area of great socio-environmental vulnerability, near a large pond and a community that uses it for economic activities and direct consumption. The community of Borzeguim - the eponymous name of the pond - has about 50 families that since 2002 protest against the placement of the landfill. Nevertheless, in 2004, was installed a sewage treatment plant, with effluent being released in the same water system impacted by landfill. The inexistence of such a study of the region that would let us know the real impact of such practices, motivated the conception of the present work. Thus, our goal is to analyze the social and environmental impacts arising from inadequate disposal of solid and liquid waste in the water resources of the community above. The specific objectives are to assess the social impact of inadequate disposal of solid waste on the population that resides in the vicinity of the landfill and to evaluate the water quality of the water system under study, identifying the parameters that exceed the limits established by CONAMA 357/2005, and simulate the behavior of self-purification of the stretch under study considering the measure of dissolved oxygen. In order to do so, we conducted semi-structured interviews with a sample of the community, including human scavengers found in the landfill, with a view at addressing the social diagnosis of the area. In order to diagnose physical and environmental quality of surface water, four campaigns were conducted, analyzing the following parameters: DO, BOD, pH, fecal coliform, E. Coli, salinity and Secchi transparency. We simulated the behavior of self-purification of the water system under study using the modeling of water quality proposed by Streeter & Phelps and the load of BOD. With that, we reached the following conclusions: 1) the landfill and STS cause problems to the community of Borzeguim, emmiting stink, provoking their rejection (by the members of other communities) and causing real estate depreciation, as well as disturbing the relationship between community and pond. 2) the landfill causes strong depletion of DO in the creek while the STS retards the reaeration system, 3) the pond is eutrophic, has excessive presence of microalgae on the surface, high rate of primary productivity and diminute photic zone. 4) the pollution load coming from the city is an important factor in the degradation of the pond. These conclusions evidentiate the indispensability of further interdisciplinary studies on the issue of solid waste disposal on the Borzeguim area to serve as a subsidy to plans for restoration of similar degraded areas and as a subsidy to plans for their subsequent sustainable management and, more immediately, as a technical foundation of any proposals for the adoption of those plans.

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Malone, Caroline E. ""Sea Water Fish in a Freshwater Pond:" An Institutional Approach to Understanding Cooperative Scarcity in the United States". Scholarship @ Claremont, 2014. http://scholarship.claremont.edu/scripps_theses/499.

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There is remarkable cooperative organization scarcity in the United States. Particularly in the credit union and worker cooperative sectors, this scarcity is not satisfactorily explained by neo-classical economic models that assume competitive conditions and profit-maximizing organizations. This paper supplements the conventional economic understandings of credit union and worker cooperative scarcity with an institutional analysis. Mechanisms of coercive, mimetic, and normative institutional isomorphism developed in DiMaggio and Powell’s theory of organizational isomorphism are applied to provide greater understanding of credit union and worker cooperative scarcity in the US. It appears that these forces of isomorphism work in conjunction with one another, as well as with competitive forces of isomorphism, to cyclically reproduce the scarcity of credit unions and worker cooperatives which prevails in the US.

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33

Edwards, Paula Kay. "The Correlation of the Concentration of Selected Metals Determined in Water and Fish Samples from a Public Pond". Digital Commons @ East Tennessee State University, 2010. https://dc.etsu.edu/etd/1774.

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The concentrations of heavy metals (Cd, Cu, Fe, Ni, Pb, Zn) were measured in water, and fish samples caught from the pond at Fishery Park in Unicoi County, TN. The water samples were collected once a week for 8 weeks. The amounts of metals in the muscle tissues, gill, and liver of the two fish species were measured. This was to determine if any correlation exists between the metal contents in water and those in the fish samples. The concentration ranges for the heavy metals found in the water samples are as follows: Zn 0.04-0.13; Cu, 0.00-0.00; Pb, 0.00-0.59; Cd, 0.0067-0.0071; Fe, 0.208-0.512; and Ni, 0.044-0.270 ppm. The concentration range for the heavy metals found in the fish tissues are as follows: Zn 0.0-0.48; Cu, 0.00-0.00; Pb, 0.00-0.43; Cd, 0.00-99.7; Fe, 25.7-1245.5; and Ni, 0.00-268.5 ppm. There was a strong correlation found between the water and fish tissue samples.

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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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35

Fairman, Christy Michelle. "Using an Occupancy Modeling Framework to Test the Effects of Habitat Variables on Pond Occupancy of Mabee's Salamander (A mabeei) and Marbled Salamander (A opacum)". W&M ScholarWorks, 2009. https://scholarworks.wm.edu/etd/1539626882.

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36

Drašar, Zdeněk. "Studie rekonstrukce rybníku Těšík v k.ú. Horní Bory". Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2018. http://www.nusl.cz/ntk/nusl-371823.

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This diploma thesis deals with the proposal of reconstuction of the pond Těšík at the level of study. The introductory part of the thesis defines the terminology and the partition of small water reservoirs. The next practical part is focused to the locality of interest and its current state leading to the necessary reconstruction. This part is followed by the design of a technical solution for reconstruction based on hydrotechnical calculations and the graphics part.

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37

Woodside, M. D. "Analysis of water quality problems in the VPI & SU Duck Ponds and suggested management alternatives". Thesis, Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/53725.

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Allochthonous nutrients were monitored during three storm events on one of the major tributaries entering the shallow VPI&SU Duck Ponds. Autochthonous nutrients were monitored for a period of ten months. During these storms, the stormwater runoff contributed large amounts of organic matter and fertilizer nutrients that settled in the ponds and during anoxic conditions, recycled to stimulate algal blooms. Alum was applied to one pond to reduce internal cycling of nutrients. A 25 mg/L dose of alum produced an aluminum hydroxide floc that settled to the bottom and afterwards, lowered othophosphate-phosphorus concentrations below 10 µg/L in the water column. The longevity of the one-time treatment in reducing the sediment-phosphate release rate is unknown because the monitoring program was not continued beyond July of 1988. A pond-treatment program involving copper sulfate was initiated to control algal blooms consisting mainly of the green alga, Chlamydomonas. Based on the complexing properties of the water, such as alkalinity and humics, a copper sulfate dose of 13.6 kg was determined to be a safe and effective dose that reduced algal densities but did not result in any visible adverse effects upon other aquatic life. Both of the pond management schemes were designed to aid managers of small urban ponds who have low operating budgets and a lack of technical equipment.
Master of Science

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38

Ebanks, Sue C. "The Common Pond Snail Lymnaea stagnalis: Extracellular Fluid Recovery in Adults and Calcification and Lead Sensitivity During Embryonic Development". Scholarly Repository, 2010. http://scholarlyrepository.miami.edu/oa_dissertations/658.

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Freshwater organisms are known to maintain hyperosmotic internal conditions despite outward diffusive loss of ions. The freshwater common pond snail Lymnaea stagnalis faces this challenge while additionally attaining the necessary ions for calcification. These are the first documented assessments of the time and mode of recovery for ions lost due to full-body withdrawal in adults of this species. Additionally, this document reports on the physiological and developmental onset of embryonic calcification and the commencement of active acquisition of shell-forming ions from the surrounding environment. The effect of water chemistry and lead (Pb) exposure on embryonic growth, development, and calcium (Ca2+) acquisition was also tested. Pharmacological and water chemistry manipulations were used to determine mechanisms for embryonic Ca2+ and HCO3-/CO32- acquisition and the sensitivity of those pathways. Lastly, L. stagnalis, was shown to have a lowest effective concentration of <1.5 µg Pb l-1 using net Ca2+ uptake, growth, and developmental endpoints in laboratory and natural waters. This is the lowest effective concentration observed for any organism to date. One of the most insightful findings reported here is the interconnectedness of the pathways for acquisition of Na+ and Ca2+ through endogenous production of H+ and HCO3- via carbonic anhydrase-catalyzed hydration of metabolic CO2. The combination of high demand for Ca2+ throughout early life stages and periodic acute demands for Na+ recovery following extracellular fluid loss apparently causes L. stagnalis to be highly sensitive to changes in water chemistry, including [Pb] in the embryos, and possibly pH. The findings reported here warn of the need to establish freshwater environmental indicators and consider raising awareness of the threat of freshwater acidification, which may be greater than that of ocean acidification.

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Florberger, Jenny. "Dagvattendammars reningseffekt : påverkande faktorer och metodik för statistisk modellering". Thesis, Uppsala University, Department of Earth Sciences, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-88846.

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Storm water is defined as runoff from precipitation such as rain or snow. It is collected in sewage disposal systems and since it mainly originates from urban areas it can contain high levels of heavy metals, nutrients and oil etc. Polluted storm water is currently treated by different methods such as wet ponds, constructed wetlands and filter strips. This study investigates these methods, which in earlier studies have shown to give varying results regarding their treatment efficiency.

This thesis has been written on commission of SWECO VIAK and was aimed at studying those parameters that may affect the treatment efficiency of nutrients and heavy metals in storm water treatment facilities (STF:s). Through literature studies the dominating treatment processes in ponds and wetlands were examined. The flow pattern was then simulated in four different storm water ponds, of varying shape and size, by using a physically based computer model. The residence time distribution for each pond could then be calculated as well as the hydraulic efficiency, which is a measure on how well the inflowing water is spread throughout a pond. Finally a multiple regression analysis was performed. This analysis examined how the reduction of lead, copper, zinc and cadmium depends on the following factors: the specific pond area, the variance of the residence time distribution, the hydraulic efficiency and the concentration of incoming metals and suspended solids. The specific pond area is a factor which is defined as the pond area divided by the reduced run off area.

The results from the multiple regression analysis indicate that an increasing content of inflowing suspended solids leads to a better treatment efficiency regarding lead and copper. The specific area showed to have some effect on the treatment efficiency, but this effect was less than that of the content of inflowing suspended solids. The reduction of cadmium depended mainly on the specific area and the incoming concentration of cadmium. An increasing reduction of zinc could to some extent be explained by an increasing specific area.

The results from this analysis and earlier studies are emphasizing the fact that adsorption to particles and sediment is one of the main processes for a good separation of heavy metals from storm water. Longer measurements series from additional treatment facilities are needed to build a statistical model which, in the future, can be used to predict the treatment efficiency of storm water ponds.

Dagvatten är regn- och smältvatten som samlas upp i avloppssystem. Då detta vatten huvudsakligen härstammar från urban bebyggelse så kan det innehålla höga halter tungmetaller, närsalter och olja med mera. Idag behandlas förorenat dagvatten bland annat genom nyttjande av dammar, våtmarker och översilningsytor. Dessa behandlingsalternativ har dock visat sig ge varierande resultat med avseende på dess reningseffektivitet.

Detta arbete har utförts på uppdrag av konsultföretaget SWECO VIAK och syftade till att studera vilka parametrar som påverkar reningseffekten av närsalter och tungmetaller i dagvattendammar. Genom litteraturstudier undersöktes de dominerande reningsprocesserna i dammar och våtmarker. Därefter modellerades strömningen i 4 dammar med varierande form och storlek. Vid detta arbete erhölls en fördelning av uppehållstiden hos vattnet för respektive damm samt ett värde på den hydrauliska effektiviteten, vilken är ett mått på hur väl det inströmmande vattnet sprids ut i dammen. Slutligen utfördes en multipel regressionsanalys.

Vid denna analys undersöktes hur reningen av bly, koppar, zink och kadmium beror av den specifika dammarean, variansen hos vattnets uppehållstidsfördelning, den hydrauliska effektiviteten samt inkommande metall- och TSS-koncentration (suspenderat material). Den specifika dammarean är en faktor vilken defineras som kvoten mellan dammens area och dess reducerade avrinningsområde.

Resultaten från den multipla regressionen tyder på att en ökad inkommande halt av suspenderat material till dammen har störst betydelse för en förbättrad avskiljning av bly och koppar. Även den specifika arean och metallkoncentrationen i inflödet visade sig ha en viss, men något mindre, betydelse. Reduktionen av kadmium berodde däremot till störst del av den specifika arean och inkommande kadmiumkoncentration. En ökad reduktion av zink förklarades till viss del av en ökad specifik area. Resultatet att halten av suspenderat material i hög grad avgör reningen samt tidigare studier understryker det faktum att adsorption till partiklar och sediment verkar vara en av de viktigaste processerna för en god avskiljning av tungmetaller. Längre mätserier från fler dagvattendammar krävs dock för att i framtiden ta fram en statistisk modell vilken skulle kunna användas till att prediktera reningseffekten.

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40

Stevenson, James Ronald. "Sustainability of brackish-water pond aquaculture systems : a farm-level analysis of economic, social and ecological dimensions in the Philippines". Thesis, University of Reading, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.427839.

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Eriksson, Linda. "Lakvattenrening och kontroll vid deponier : granskning och sammanställning". Thesis, Uppsala University, Department of Earth Sciences, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-88869.

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If not purified leachate from landfills would cause damages on the environment. At most landfills in Sweden local treatment of leachate is achieved, at the rest the leachate is transported to sewertreatment. While no comprehensive legal provisions for discharge exist in Sweden there is a difference in discharges between the installations for landfill. If no comprehensive legal provisions is produced guidance must improve.

Treatment of leachate and self monitoring system at fifteen installations in Sweden has been studied and compared. A study of literature about different treatment solutions has also been performed. Practical information about the landfills has been gathered through visits. Processes of treatment described in literature correspond to measures. Variations exists between the self monitoring systems at the installations both between parameters for analyses, how often controls take place and were testpoints are situated.

Knowledge of reactions and techniques for treatment of compounds common in leachate exist. Further research about compounds whose effect we do not know for certain must be achieved.

Lakvattenrening och egenkontrollprogram vid femton deponier i Sverige har studerats och jämförts. En litteraturstudie angående olika reningstekniker har även utförts. Information om deponierna och reningsprocesserna har inhämtats via studiebesök och miljörapporter. Vid jämförelse av rening har olika processer studerats separat. Den beskrivning av processerna som finns i litteraturen stämmer väl med uppmätta resultat. Exempel på detta är ammoniumhalter som reduceras i luftad damm, halter totalkväve som minskar genom rening i Satsvis Biologisk Reaktorteknik och reducerad halt suspenderat material som inträffar vid rening genom markfilter. Egenkontrollprogrammen vid de olika deponierna varierar dels i avseende på vilka parametrar som kontrolleras och dels hur ofta kontroller utförs och var provpunkter är belägna.

För de vanligast förekommande ämnen som existerar i lakvatten finns kunskap om reaktioner och fungerande tekniker för rening. Problem uppstår för de ämnen vilkas reaktioner och förändringar man ej känner till. Farhågor finns dessutom att det i lakvatten finns föreningar vars existens och verkan vi ej känner till. På grund av detta krävs ytterligare forskning på lakvatten.

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42

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

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

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Nipper, Joel. "Measurement and modeling of stormwater from small suburban watersheds in Vermont". ScholarWorks @ UVM, 2016. http://scholarworks.uvm.edu/graddis/444.

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Despite decades of U.S. water quality management efforts, over half of assessed waterbody units were threatened or impaired for designated uses in the most recent assessments, with urban runoff being a leading contributor to those impairments. This cumulative research explores several aspects of urban runoff dynamics through a combination of field study and modeling. Stormwater ponds are ubiquitous in developed landscapes due to their ability to provide multiple forms of treatment for stormwater runoff. However, evolving design goals have reduced the applicability of much of the early work that was done on pond effectiveness. In this study, we instrumented a recently constructed detention pond in Burlington, VT, USA. Flow gaging demonstrated that the pond achieved a 93% reduction in event peak flow rates over the monitoring period. Storm sampling showed that the pond significantly reduced total (TN) (1.45 mg/L median influent, 0.93 mg/L median effluent, p < 0.001) and total phosphorus (TP) (0.498 mg/L median influent, 0.106 mg/L median effluent, p < 0.001) concentrations over the events sampled. A loading analysis estimated the TN and TP removal efficiencies for the pond to be 23% and 77% respectively. Lastly, temperature data collected from the pond showed that during the summer the pond accumulates considerable heat energy. This study adds to the body of literature on detention pond performance, and raises concerns about the extensive use of stormwater ponds in watersheds where thermal stress is a concern. EPA SWMM is a widely used urban hydrologic, hydraulic and water quality model, though its application can be limited due to its deterministic nature, high dimensional parameter space, and the resulting implications for modelling uncertainty. In this work, I applied a global sensitivity analysis (SA) and evolutionary strategies (ES) calibration to SWMM to produce model predictions that account for parameter uncertainty in a headwater tributary case study in South Burlington, VT, USA. Parameter sensitivity was found to differ based on model structure, and the ES approach was generally successful at calibrating selected parameters, although less so as the number of concurrently varying parameters increased. A watershed water quality analysis using the calibrated model suggested that for different events in the record, the stream channel was alternately a source and a sink for sediment and nutrients, based on the predicted washoff loads and the measured loads from the stream sampling stations. These results add to the previous work on SWMM SA, auto-calibration, and parameter uncertainty assessment. Lastly, given the extent of eutrophication impairment in the U.S., I compared TN and TP data collected in these original works with national and regional datasets. TN concentrations sampled in this work were generally commensurate with values reported elsewhere, however TP data were not. Drainage area attributes and an event based rainfall runoff analysis of the study catchments provided circumstantial support for the idea that runoff from lawns is driving the high TP loads in Englesby Brook. The role of pet wastes is considered as a potentially fruitful area for further research.

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Petersen, Jacques R. "A geochemical investigation of ground water and soils affected by evaporation pond seepage, at the Namakwa Sands Mineral Seperation Plant(MSP)". Master's thesis, University of Cape Town, 2004. http://hdl.handle.net/11427/4218.

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Bibliography: leaves 78-81.
Evaporation ponds are used for treating wastewaters in arid regions worldwide. Namakwa Sands an Anglo American plc operation, mines heavy minerals along the semi arid West Coast of South Africa. An acid effluent is generated during treatment of these heavy minerals. The effluent is neutralized and disposed of into unlined evaporation ponds. Seepage from the ponds affects the surrounding environment as well as the subsurface waters. The main objective of this study was to investigate the effects of the seepage on the groundwater resources and potential implications for contaminant migration in the subsurface environment.

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Aza-Gnandji, Cocou Davis Ruben. "Salinity of irrigation water in the Philippi farming area of the cape flats, Cape Town, South Africa". University of the Western Cape, 2011. http://hdl.handle.net/11394/2921.

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Magister Scientiae - MSc
This research investigated the nature, source and the spatial variation of the salinity of the water used for irrigation in the urban farming area of Philippi, which lies in the Cape Flats region of the Cape Town Metropolitan Area, South Africa. The irrigation water is mainly drawn from the Cape Flats aquifer, and pumped into ponds for eventual crop irrigation. Water samples were collected in summer and in winter from fifteen selected sites using standard water sampling procedures. Each site consisted of one borehole and one pond. The samples were routinely analyzed for salinity levels, and concentrations of major and minor ions. From the same boreholes and ponds, water was sampled in summer for isotope analysis to assess effects of evaporation on the water quality and salinity. Descriptive statistics were used to display the variation in range of specific ions in order to compare them with the recommended ranges. Geographical Information Systems analysis described the spatial distribution of the salinity across the study area, and hydrogeochemical analysis characterized the various waters and detected similarities between the water samples in the study area and other waters found in the Cape Flats region. In addition, the US salinity diagram classification of irrigation water developed by Richards (1954) was used to assess the current suitability of groundwater and pond water samples collected during the entire sampling period for irrigation activities. The research indicated that the concentrations of some ions such as chloride, nitrate, potassium and sodium exceeded in places in the study area, the target range values set by the Department of Water Affairs and Forestry (DWAF, 1996) and the Food and Agriculture Organization (Ayers and Westcot, 1985). It revealed that borehole and pond water were mostly brackish across the area regarding their total dissolved salts content, and fresh water was only found in the middle part of the study area. The research found that sea water does not intrude into the aquifer of the study area, and the accumulation of salts in groundwater and soil in the study area is mainly due to the agricultural activities and partially due to the natural movement of water through the geological formation of the Cape Flats region. The conceptual model of the occurrence of the salinization process supported these findings. From this investigation it is understood that the groundwater and pond water in the study area were generally suitable for irrigation purposes but they have to be used with caution as the vegetables are classified as sensitive and moderately sensitive to salt according to DWAF Irrigation water guidelines (1996). The quality of these waters was mainly affected by the land use activities.
South Africa

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Luksanaree, Maneechot. "Impacts of Future Climate Change in Water Resources Management at the Chao Phraya River Basin, Thailand". Kyoto University, 2020. http://hdl.handle.net/2433/259028.

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Marcin, Richard, i Matej Mucha. "THEORETICAL STUDY TO IMPROVE THE ENERGY BALANCE IN WASTEWATER TREATMENT PLANT : Investigation of microalgae photobioreactor in biological treatment step and open algal pond in reject water treatment in Uppsala and Västerås". Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-29917.

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The self-treatment system of nature cannot handle man-caused high rate water pollution on its own, therefore cleaning in wastewater treatment plant (WWTP) is necessary to avoid eutrophication – excessive enrichment of nature by nutrients. Current technologies applied in WWTPs are old, outdating and highly energy demanding, especially biological treatment step generally requires large amount of energy for aeration of water. The alternative to current system could be microalgae treatment step, which would use green algae to consume pollutants present in the waste water, namely nitrogen, phosphorus and heavy metals. Via photosynthesis it could produce oxygen required for biological oxidation of organic matter. Furthermore carbon source is necessary for microalgal growth, this can be added to the water as CO2 produced in other industries and so decrease global greenhouse gas footprint. Co-digestion of microalgae with undigested wastewater sludge under mesophilic conditions can give a synergic effect for biogas production, therefore harvested and co-digested microalgae could contribute to positive energy balance of WWTP. Full-scale microalgae cultivation in WWTP can be achieved only when good grow is guaranteed. This is a result of many factors, particularly access to nutrients, light condition, water temperature, and pH. The goal of master’s thesis was to understand and evaluate main factors influencing algal growth using literature review, propose design of microalgae treatment step with artificial lights and evaluate energy balance, of wastewater treatment plants in Uppsala and Västerås with new design. The work proposed two different designs of microalgae treatment steps, modelled in Excel and applied to current state of municipal WWTP in Västerås and Uppsala with belonging satellite plants. The first design of microalgae activated photobioreactor (MAASPBR) aimed to replace current biological treatment step. This is possible in Västerås and Uppsala WWTPs if microalgae can consume 75% of total nitrogen (Ntot) and produce at least 13.5 and 2.4 tonne O2/day in Västerås and Uppsala respectively. The sensitivity analysis showed that minimal volumetric algal yield of 0.15 kg/m3 ,day and 0.25 kg/m3 ,day is required for Västerås and Uppsala respectively, when oxygen production rate of 1.92 kg O2/kg microalgae is assumed. Furthermore harvested and co-digested algae with sewage sludge contributes to significant increase of biogas production and negligible transportation energy increase. The second design of open algal pond for reject water (OAPRW) aims to cultivate microalgae on reject water with high concentration of nutrients, generated in sludge centrifuge. The model assumed high algal growth due to excessive amount of nutrients and increased water temperature to 24°C. Results show a possible 23% and 20% electricity saving on blowers in the biological treatment in Västerås and Uppsala respectively. Both models have positive impact on energy balance in all WWTPs, however MAASPBR has greater uncertainties, because this type of photobioreactor has not been tested unlike OAPRW which has been tested in pilot plant scale.

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Girleviciute, Aiste. "Uppföljning av reningsfunktionen i Steningedalens våtmark". Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-353512.

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Dagvattnet från Märsta är belastat med bland annat tungmetaller och näringsämnen. Vattnet hamnar i Märstaån och transporteras vidare ut till Mälaren. Steningedalens våtmark är ett dammsystem som renar och fördröjer en del av Märstaåns flöde före transport ut mot Mälaren. Syftet med detta självständiga arbete på kandidatnivå har varit att undersöka anläggningens reningsfunktion med hjälp av sedimentprovtagning. Sedimentprover har tagits vid in- och utloppet och en kemisk analys av dessa har utförts i ett ackrediterat laboratorium. Resultaten från in- och utloppet har jämförts för att se om det sker en minskning av föroreningar genom systemet. Fem sedimentfällor har placerats ut i delar av dammsystemet för att undersöka sedimentfördelningen och muddringsbehovet i anläggningen. Resultatet av studien visade att dammsystemet har en god vattenreningsfunktion med avseende på tungmetallerna bly, nickel, kadmium, krom, koppar och zink samt näringsämnet fosfor. Anläggningen har bedömts att vara i behov av muddring.
In Märsta, the storm water is contaminated with heavy metals and nutrients (nitrogen and phosphorus) among other pollutants. The water emits to the river Märstaån and further to the lake Mälaren. The wetland of Steningedalen is a pond system that delays part of the stream in Märstaån and purifies the water on its way through the system. This independent project is based on investigation of the purification functioning at Steningedalen wetland. The investigation has been done by sediment sampling and analysis. The samples were taken from the inlet and the outlet of the pond system. Chemical analysis has been made on these samples in an accredited laboratory. The results were compared in order to see if there is a trend through the system. Five sediment traps were placed in parts of the system to study the distribution of the sediment and the need of dredging. The results of the study have concluded that the stormwater pond system has a good water purification function with regard to heavy metals lead, nickel, cadmium, chromium, copper and and zinc aswell as the nutrient phosphorous. The study has also shown that the system is in need of dredging.

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Jackson, Kate Maree. "Suspended solid levels in two chemically dosed sediment retention ponds during earthworks at SH20, Auckland". The University of Waikato, 2008. http://hdl.handle.net/10289/2298.

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Earthworking activities have the potential to accelerate soil erosion through vegetation clearance and soil compaction processes. The eroded sediment can have many detrimental effects on receiving aquatic environments, and thus its discharge is controlled under the Resource Management Act, 1991. Two chemically dosed sediment retentions ponds at the SH20 extension project in Mount Roskill, Auckland were investigated, and the impact of the discharge of one of these ponds on a receiving waterbody was assessed using the Stream Ecological Valuation (SEV) method. Rainfall and suspended solid data was collected for a nine month period between November 2006 and August 2007, although sampling did not commence at one of the ponds until March 2007. Two SEV samples were undertaken within the receiving waterbody; one in November 2006 and the other in November 2007 to assess environmental changes resulting from the sediment retention pond discharge. The suspended solids results measured within the sediment retention ponds during this study were much lower than those reported by other studies on earthwork sites. This is believed to be due to the effective implementation of sediment and erosion control measures onsite. The Somerset Road pond was very effective at removing suspended solids throughout the sampling period, with the majority of suspended solid removal occurring in the forebay as it typically did not become full enough to overflow into the main pond. When the forebay was full of water, the PAC dosing system resulted in large reductions in suspended solid levels over a short horizontal distance within the forebay. A smaller amount of suspended solid reduction was achieved in the main pond, predominately through dilution, with the major function of the main pond being additional storage capacity for runoff. Discharge from the Somerset Road Pond was not continuous due to low water levels in the main pond. However, when discharge did occur, the suspended solids levels were very low compared with other studies investigating sediment retention pond discharge. The Richardson Road pond was less effective at removing suspended solids due to the flow regime within the forebay. There were two runoff channels entering the forebay, as well as a continual flow of groundwater. Only one of the runoff channels was directly dosed with PAC, and as the water level in the forebay was typically at, or just below, the level spreader at all times, there was a decreased potential for the PAC to become evenly distributed through the forebay and achieve dosing of all runoff. Furthermore, the main pond discharged continuously during the study period, resulting in reduced residence times of runoff within the pond system. Nonetheless, the discharge from the main pond was much lower than other studies, implying suspended solid reduction was being achieved. The SEV method indicated that the receiving environment was already degraded due to modifications to the riparian vegetation, increased dissolved oxygen demand, and moderate bank erosion. This was reflected in the macroinvertebrate population, with only pollution tolerant taxa being collected, thus limiting the use of macroinvertebrates as an assessment tool in this study. However, the SEV method, which assesses a wide range of ecological functions, implied that very little environmental change occurred as a result of the sediment retention pond discharge. A small increase in deposited sediment was observed on the stream bed, however indications are that deposited sediment is rapidly washed away once earthworks are completed. Thus this deposited sediment may not have a permanent impact within the receiving environment.

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Žydelis, Renaldas. "Vandens kokybės parametrų kaita ir Akademijos tvenkinio įtaka jų pokyčiams Dotnuvėlės upėje". Master's thesis, Lithuanian Academic Libraries Network (LABT), 2013. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130621_143233-75055.

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Lietuvoje kaip ir daugelyje pasaulio šalių dedama daug pastangų, kad vandenų tarša mažėtų. Pagal valstybinio monitoringo duomenis nustatyta, kad Lietuvos upėse vis dar išlieka didelės biogeninių medžiagų koncentracijos. Vandens tarša yra viena iš pagrindinių ES aplinkosaugos problemų. Norint išsiaiškinti pagrindines vandens taršos problemas, būtina atlikti nagrinėjamos upės vandens kokybės parametrų matavimus. Tam tikslui nuo 2010-11-06 iki 2013-05-07 buvo atliekami vandens kokybės tyrimai, kurių metu buvo fiksuojami šie parametrai: vandens lygis, ištirpusio deguonies koncentracijos, aktyvi vandens reakcija (pH), bendrosios mineralizacijos, elektrinio laidžio, nitratų ir vandens temperatūros kaita. Vandens kokybės parametrai matuoti aukščiau ir žemiau Akademijos tvenkinio, kuris susidarė 1968 m. ant Dotnuvėlės upės ties Akademijos gyvenviete. Pagal minėtus duomenis buvo nustatyta vandens kokybė atskiruose Dotnuvėlės ir jos intako Kačiupio upių taškuose. Atlikus tyrimą buvo nustatyta, kad Akademijos tvenkinys sąlygoja nitratų pasiskirstymą upėje, t. y. pastebėtas nedidelis nitratų padidėjimas upėje žemiau tvenkinio. Nustatyta, kad bendroji mineralizacija rudenį didėjo, žiemos metu svyravo, o pavasarį mažėjo. Pagal ištirpusio deguonies kiekį visose matavimo stotyse vanduo atitiko labai blogą, blogą, vidutinę, gerą arba labai gerą būklę. Vandens lygis Akademijos tvenkinyje tiriamuoju laikotarpiu svyravo 0−19 cm ribose stoties „O“ atskaitos atžvilgiu. Kitų išmatuotų vandens... [toliau žr. visą tekstą]
In Lithuania, as well as in other countries of the world, great efforts are made to reduce water pollution. According to the national monitoring data, there is still a high concentration of biogenic substance in Lithuanian rivers. Water pollution problem is one of the key EU environmental issues. In order to find out the main water pollution problems, it is necessary to conduct the measurements of water quality parameters of the investigated River. For this purpose, from 06/11/2010 to 07/05/2013 water quality measurements were carried out, during which values of the following parameters were recorded: water level fluctuations, dissolved oxygen concentration, pH, total dissolved solids, the variation of nitrates and water temperature. Water quality parameters were measured upstream and downstream the pond at Akademija settlement. In accordance with the given data, water quality was identified in several points of Dotnuvėlė and Kačiupio rivers. The research revealed that the pond of Akademija determines nitrate distribution in the river, i.e. a slight nitrate increase was observed in the river below the pond. It was disclosed that in autumn total dissolved solids increased, in winter the concentration varied and it decreased in spring. According to the amount of dissolved oxygen at all measurement stations, water corresponded to a poor, extremely poor, moderate, good or extremely good condition. During the research period, water level in the pond of Akademija ranged from 0-19... [to full text]

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