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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Investigation of the efficacy of BDOC protocols used in biofilm measurement and monitoring

Olugbuo, Zita January 2017 (has links)
A research report submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in Partial Fulfilment of the requirements for the degree of Masters of Science in Engineering, 2017 / Access to good quality drinking water is essential for the maintenance of public health. To guarantee a steady supply of good quality water, water treatments plants are designed to provide potable water that meets national and, where necessary, local water quality standards. While the protection of natural water resources against pollution, and proper treatment of water at treatment plants are both crucial to the provision of safe drinking water, the reality is that the quality of treated water can degrade during distribution. Microbial proliferation within distribution systems can cause problems such as unpleasant tastes and odours as well as the proliferation of pathogenic microorganisms. For most utilities, it is biofilm that grows on pipe surfaces that act as permanent inocula continuously inoculating the bulk water as it flows through the distribution system. Distribution system biofilm growth and the resulting impact on water quality can be minimized by various treatment processes, designed to remove biodegradable organic matter (BOM) from the water. The removal of BOM is of great importance to water utilities because it eliminates bacterial regrowth and the many associated water quality issues. Hence, the spatial and temporal mapping of biodegradable organic carbon (BDOC) offers water utilities an effective strategy in managing the BOM in the distribution system. This research is aimed at evaluating the applicability of BOM measurement protocols to monitoring biostability and biofilm formation potential within a drinking water distribution system (DWDS). This study specifically investigated the efficacy of a simplified version of the high-density BDOC test as a protocol for monitoring BDOC in finished water. The high-density BDOC protocol was found to be a more streamlined approach in contrast to the assimilable organic carbon (AOC), and provides a suitable monitoring mechanism for lowering biofilm formation potential in DWDSs. / CK2018
22

Piped water access, child health and the complementary role of education : panel data evidence from South Africa

Wapenaar, Korstiaan Erich January 2017 (has links)
Thesis (M. Com. (Economics))--University of the Witwatersrand, Faculty of Commerce, Law and Management, School of Economic & Business Sciences, 2017 / This study establishes the causal impact of piped water access on child health in rural South Africa (2008 – 2015) through the use of a panel dataset and a quasi-experimental sample space. By employing an ordinal measure of child health as the dependent variable within ordinal probit, fixed and random effects, propensity-score matched difference-in-difference and system-GMM estimators, it is demonstrated that positive health benefits for children with access to piped water are observed if and only if the minimum level of educational attainment of the primary-caregiver is equal to or greater than 7 years. This finding of complementarity is demonstrated to be a function of an individual’s (in)capacity to evaluate water quality: people below this threshold suffer from a piped water bias, place insufficient weight on the observable characteristics of water when determining water quality and are subsequently less likely to treat piped water preceding consumption. The interactional effect estimates are statistically significant at the 5% level with the impact ranging from 1.617 to 2.008 levels. / GR2018
23

A measure of service quality on water in Lepelle-Nkumpi Municipality in the Limpopo Province

Shongwe, Nkosinathi Sipho January 2007 (has links)
Thesis (MBA.) -- University of Limpopo, 2007 / The residents of Lebowakgomo in Lepelle-Nkumpi Municipality experience numerous inequalities in relation to water services provision. Some of the residents protest towards the inequalities through refusal to pay for the water services. The confrontational non paying residents field questions which the municipality can hardly answer. The problem of refusal to pay is of the magnitude that recently the municipality had to go house-to-house pleading with the inhabitants to pay if the municipality was to continue to provide water services. The specific objectives of this study were three-fold: (1) to determine water service quality using residents’ perceptions on water services in Lebowakgomo, (2) to determine residents’ expectations and perceptions on water services in Lebowakgomo, and (3) to determine the residents’ perceptions on water service quality and customer satisfaction in Lebowakgomo using age, gender, qualification and suburb. A questionnaire comprising five dimensions, namely, tangibles, reliability, assurance, empathy and responsiveness, was compiled to collect data from three suburbs of Lebowakgomo in Lepelle-Nkumpi Municipality. The original sample size was 120, with 9 becoming spoiled due to missing data. The independent variables comprised age, qualification, suburb and gender. Most of the data were analysed for kurtosis and skewness and with the exception of one variable, the rest of the data did not conform to parametric analysis criteria. The major findings of this study indicated overall negative perceptions of residents’ on four dimensions of empathy, reliability, responsiveness and assurance on water service quality which implied that the residents were dissatisfied with the service and called on management to use SERVQUAL as a valid model of assessment to identify areas requiring immediate attention for service improvement. On the other contra positive it was revealed that the municipality was doing well on the tangibles dimension. ix The study recommended use of SERVQUAL in measuring quality of other services within the constitutional competencies of the municipality and further research to investigate age contribution to service quality.
24

Spatial and temporal variability in water quality characteristics of the Swartkops Estuary

Pretorius, Liaan Marié January 2015 (has links)
Water quality characteristics of the heavily urbanised and industrialised Swartkops River catchment in the Eastern Cape has been the focus of several studies since the 1970s. Overloaded and poorly maintained wastewater treatment works (WWTW), polluted stormwater runoff and solid waste have had a negative impact on the water quality status of the Swartkops River and estuary. Past studies have revealed that a distinct relationship exists between land use activities and the water quality of the Swartkops Estuary, which in turn has raised concerns pertaining to the ecological, economic, recreational, and cultural value of the estuaryThe Swartkops Estuary has a Present Ecological State (PES) of Category D(1) and a Recommended Ecological Category (REC)(2) of a C (Van Niekerk et al., 2014). It is known that effective management of anthropogenic impacts on coastal systems requires a thorough understanding of the system’s biological responses to wastewater discharges and to hydrologic changes. For this reason, the objective of this study was to determine the current water quality status of the Swartkops Estuary, and to gain greater insight into factors controlling eutrophication. This was important as outdated water quality information was used in the Swartkops Integrated Environmental Management Plan (Enviro-Fish Africa, 2011) due to a lack of current data. To determine the current water quality status of the Swartkops Estuary the present study investigated spatial and temporal variability in physico-chemical parameters, nutrients, phytoplankton biomass and community composition, faecal bacteria, and “where possible” related this to historical water quality data. In general, points of entry into the estuary were investigated for their impact on nutrient enrichment and the bacteriological status of the estuary. Water quality surveys were completed in September 2012, November 2012, February 2013, May 2013 and August 2013The present study found evidence to suggest that water is not flushed as efficiently from the estuary as was previously the case, and that the natural hydrology of the estuary has been modified. These changes appear to be the effect of large volumes of wastewater discharges from the wastewater treatment works (WWTW), which has led to the additional stresses of increased vertical stratification and reduced vertical mixing. A build-up of dissolved inorganic nutrients has given rise to persistent eutrophic conditions and phytoplankton blooms occurring from the middle reaches to the tidal limit of the estuary. These findings were associated with a generally well oxygenated estuary; however, bottom water hypoxic conditions were recorded in the upper reaches of the estuary on two occasions and were generally associated with bloom.forming flagellates. Elevated concentrations of inorganic nutrients stimulated phytoplankton to attain high biomass ranging from 0 to 248 g l-1 (31.8 6.56 g l-1). All nutrients displayed positive linear gradients from the mouth to the tidal limit, showed significant (p < 0.05) temporal and spatial variability, and were significantly (p < 0.05) correlated with phytoplankton biomass. Phytoplankton blooms (> 10 000 cells ml-1) of several different groups were recorded from the middle reaches of the estuary to the tidal limit. Diatoms were the dominant group during increased freshwater inflow (at mean daily flow rate of 2.14 m3 s-1) and low DIP levels, whereas flagellates were generally the dominant group during reduced flow and under higher nutrient levels. Although the different tidal stages had no effect on phytoplankton biomass per se, it did support co-existance between phytoplankton groups. This was noted during the spring ebb tide in September 2012 (i.e. flagellates, diatoms and dinoflagellate) and in February 2013 (i.e. dinoflagellates, diatoms and chlorophytes). Phytoplankton blooms have become persistent in the middle to upper reaches of the estuary where chlorophyll-a was > 20 µg l-1 and cell density exceeded 10 000 cells ml-1; a situation not reported in previous studies. The Motherwell Canal was and still is the main source of nitrogen (generally in the form of ammonium) to the estuary, whereas the Swartkops River is still the primary source of phosphorus to the estuary. Since the stormwater canal services the large residential area of Motherwell where leaks in the sewer system, the dumping of night soil buckets, and faulty pumps are often reported, polluted discharges from the Motherwell Canal can enter the canal at any given point. In contrast to the canal, DIP loading from the Swartkops River to the estuary generally occurred under conditions of low flow, whereas nitrogen showed no apparent relationship. Faecal bacteria originating from the Motherwell Canal had the most profound effect on the bacteriological status in the middle reaches of the estuary, whereas the Swartkops River had an intermediate effect due to bacteria die-offs occurring between the point of release from the WWTW to the riverine reaches and the tidal limit of the estuary. Nevertheless, Escherichia coli and enterococci levels are still high, especially in the summer months rendering the estuary unsafe for recreation during this season. Historical data on trace metals in the water column were limited and thus observations from the present study could not be concluded with much confidence. However, preliminary data suggest that levels of copper, zinc, iron and cadmium have increased by at least 90% in the estuary, at the tidal limit of the estuary and in the Markman and Motherwell canals. High inputs of nutrients, trace metals and faecal bacteria to the estuary from land-use activities indicate the necessity for remedial actions with the main objective being to conserve and protect the estuary’s recreational, ecological and economic functions.
25

Sample preparation techniques for determination of total metal content in wastewater treatment plants in Gauteng Province

Dimpe, Mogolodi 23 April 2015 (has links)
M.Sc. (Chemistry) / Prosperity for South Africa depends on the sound management and utilization of many resources, with water playing a crucial role. Located largely in a semi-arid part of the world, South Africa’s water resources are, in global terms, scarce and extremely limited. A key environmental problem facing South Africa is water pollution. This arises from many sources, including mining and industrial effluents, and runoff of biocides, nutrients and pathogens from agricultural lands, urban areas and informal settlements with poor sanitation. The consequences are often severe, including among other impacts, habitat destruction, reduced oxygen levels, fish kills and loss of human life. Inorganic and organic pollutants as well as microbes are the main constituents of the effluent from the domestic, mining, agriculture, metal electroplating, petrochemical and transport industries. The presence of pollutants in environmental systems is of concern because ultimately, they are incorporated into drinking water and various food chains. Therefore, the overall focus of this study was mainly metals analysis in wastewater systems before and after treatment processes so as to establish the efficiency of the treatment processes....
26

Defluoridation of groundwater using vermiculite modified with hexadecyltrimethylammonium: a case study of Siloam Village, Limpopo Province, South Africa

Ologundudu, Tayo Oladipo 05 1900 (has links)
MENVSC / Department of Hydrology and Water Resources / See the attached abstract below
27

The use of water quality, aquatic species composition and aquatic habitat conditions to access the river health condition of the Nzhelele River, Limpopo Province, South Africa.

Mokgoebo, Matjutla John 01 1900 (has links)
Health condition of a river is a necessity for the sustainability of aquatic ecosystems. River health status of the Nzhelele River was assessed through the use of water quality, macroinvertebrate taxa composition and aquatic habitat conditions. The study was conducted along the Nzhelele River in Limpopo Province of South Africa where the river transcends six tribal villages. The objectives were to assess water quality conditions in order to determine the magnitude of pollution impact, to correlate species diversity and water quality parameters, to measure the size of degraded areas with respect to species richness and to develop a model for managing river health condition of the Nzhelele River. Data were collected monthly between February and December 2016 (early autumn to mid-summer). Macroinvertebrates were sampled where water samples were collected to ensure that the relationship between water quality and macroinvertebrates was adequately correlated. Water quality parameters that were analysed were pH, stream temperature, river velocity, conductivity, Dissolved Oxygen, Total Dissolved Solids, nitrates, nitrites and chlorine. Assessment of habitat conditions was done through the assessment of habitat and riparian zone integrity. One-way ANOVA was used to determine if there were significant differences between the six sampling areas in terms of water quality and aquatic species composition. Principal Correspondence Analysis (PCA) was used to correlate water quality and macroinvertebrate data. The results indicated that water quality parameters significantly differed among the six sampling sites and that also explained the variations in diversity of macroinvertebrates that were sampled from the six sampling sites. Pollution tolerant organisms constituted a total of 46.7% and the remaining 53.3% represented pollution sensitive organisms. PCA results showed positive and negative correlations between macroinvertebrates and water quality parameters to indicate variations in the levels of pollution along the Nzhelele River. Habitat integrity results indicated that the Musekwa sampling site was the most degraded and had lower species diversity. The Ratio of Ephemeroptera, Plecoptera and Trichoptera (EPT) and Chironomidae Abundances should be reviewed to read as Ratio of EPT and Chironomidae-Thiaridae Abundances in order to strengthen the study of the relationship between pollution tolerant and pollution sensitive organisms. / Environmental Sciences / Environmental Science
28

Assessment of the impact of water and sediment quality on aquatic macroinvertebrate assemblages in the Blyde River of the Olifants River System, Limpopo Province

Malakane, Karabo Concelia January 2019 (has links)
Thesis (M.Sc. (Zoology) -- University of Limpopo, 2019 / The Olifants River is one of the major river systems in South Africa, providing water for industries, mines, agricultural and domestic activities. Consequently, the river has turned out to be one of the most polluted rivers in South Africa. The Blyde River is an important tributary of the Olifants River, known for its continuous flow and good water quality. However, the recent increase in human activities such as, commercial agricultural and large-scale forestry practices in the catchment may have a negative impact on the quality of the water, which may consequently affect the aquatic biota community structure. The aim of the study was to assess the water and sediment quality of the Blyde River using aquatic macroinvertebrates as bioindicators and the South African Scoring System version 5 (SASS5) protocol was followed. Seven sampling sites were selected at Blyde River and five samples were collected per site. Collected macroinvertebrates were identified to family level and classified according to their tolerance levels to pollution at the University of Limpopo Biodiversity Laboratory. In addition, seasonal readings of the physico-chemical parameters such as, pH, dissolved oxygen (DO), temperature, salinity, total dissolved solutes (TDS) and electrical conductivity (EC) were recorded in situ using YSI Model 554 Datalogger with a 4 m multiprobe and a Mettler Toledo SevenGo™. Most of the physico-chemical parameters recorded at Blyde River were within the South African water quality guidelines for aquatic ecosystems. Metals such as, As, Al, Ba, B, Cd, Cr, Co, Cu, Fe, Pb, Mn, Ni, Se, Ag, Sr, Sn, Ti, V, and Zn were tested from the water column, sediments and macroinvertebrate tissue. Almost all the metals analysed from the water column and sediments were within the quality guidelines. Out of the twenty tested metals, As, Ag, Cu, and Zn exceeded the recommended quality guidelines in the water column at some sites. Only As, Cr and Cu exceeded the recommended quality guidelines in the sediments. The most abundant macroinvertebrates were from the orders Ephemeroptera, Diptera, and Trichoptera at all sites. There was a similar macroinvertebrate community structure across the sites, supported by the positive correlation analysis among the sites (r > 0.4). Wildlife Estate and Wildrivers Estate had the highest and lowest numbers of sensitive macroinvertebrates respectively. The highest percentage of iv sensitive macroinvertebrate taxa was recorded in winter and the highest percentage of tolerant species was recorded in summer. This was also supported by the SASS indices, the SASS score, number of taxa and average score per taxon (ASPT) were highest in winter, followed by autumn, spring and lowest in summer. The overall SASS indices showed that the water quality condition at most of the sites at Blyde River could be considered as good. All the seven sites on average fell under ecological band A and B, except for the Wildrivers Estate, thus, the water quality status of the river could be described as unmodified and largely natural with few modifications. / VLIR
29

Assessing the effects of water and sediment quality on aquatic macro-invertebrate diversity in the Steelpoort River, Olifants River System, Limpopo Province

Matlou, Katlego Shirley January 2017 (has links)
Thesis (M.Sc. (Zoology)) -- University of Limpopo, 2017 / In this study data was collected to establish if the water and sediment quality of the Steelpoort River has any effects on macro-invertebrate species. The Steelpoort River is a tributary of the Olifants River system but not much data about the water quality is available. The Steelpoort River is a perennial river (Ashton et al. 2001) situated west of Burgersfort and from there it flows in a north- easterly direction and converges with the Olifants River in the Drakensberg near Kromellenboog. High silt levels in the river, increases the risk of flooding and leads to the smothering of in-stream habitats resulting in loss of some invertebrate and fish species. Sampling of the water, sediment and macroinvertebrates was conducted quarterly at the Steelpoort River at five sites. One site was above the impoundment (De Hoop Dam) and the rest were below the impoundment. A handheld YSI 556™ Multi Probe System (MPS instrument and a Mettler Toledo SevenGo™ conductivity meter were used to measure the physico-chemical characteristics at the sites. The macroinvertebrates were sampled using the SASS 5 bio-assessment protocol (Goodyear & McNeill 1999, Dickens & Graham 2002). Macro-invertebrate samples were collected using a 400 mm x 400 mm SASS net with a 250 μm mesh size. The substrate was disturbed for a period of two minutes to free macro-invertebrates from the substrate. The SASS score for each site was evaluated in the field for three of the five samples. The macro-invertebrate samples were preserved in 70% ethanol and sorted to family level in the University of Limpopo’s Biodiversity laboratory. For the majority of the physico-chemical parameters the most elevated were detected downstream and lowest concentrations were detected upstream. Analysis of variance (ANOVA) indicated that there were no significant differences for electrical conductivity, salinity, and TDS, between the sites (p>0.05). There were however significant differences in the temperature, dissolved oxygen, turbidity, and pH concentrations (p<0.05). The majority of the metals and metalloids in the water (Fe, Mn, V, Co, Zn, Ba, and Cu) were highest at Tiershoek (Site1) and lowest at Steelpoort (Site 4) and Burgersfort Bridge (Site 5).The mean metal concentrations collected showed elevated levels for chromium, copper and zinc, which were above the CCME sediment guidelines. The most abundant macroinvertebrates were from the family Ephemeroptera which are pollution sensitive and good indicators of pollution in aquatic ecosystems. When using the interpretation of the SASS 5 results from Chutter 1995, the mean Average Score Per Taxa (ASPT) scores show that the water quality for Tiershoek (Site 1) and Polopark (Site 3) is natural but the habitat diversity has been reduced. For De Hoop (Site 2) and Steelpoort (Site 4), the mean ASPT score shows that there is some deterioration in the water quality. Finally, for Burgersfort Bridge (Site 5), the mean ASPT score indicates that there is major deterioration in the water quality. Primer statistical analysis indicated that the average dissimilarity between sites showed that the highest dissimilarity was between Tiershoek (Site 1) and Burgersfort Bridge (Site 5) which was conclusive with the results from the macro-invertebrate count and SASS, indicating that there is diverse difference from upstream to downstream. CCA indicated positive correlations between nutrients detected at Steelpoort with Athericidae, Tabanidae, Gomphidae, Baetidae, Elmidae, Planaria, Psephenidae, and Libellulidae which was indicated that water chemistry characteristics exert influence on macroinvertebrates. The results showed that there is degradation of the water quality in river from upstream to downstream with more pollution tolerant species being abundant at Steelpoort (Site 4) and Burgersfort Bridge (Site 5). The most favourable season was autumn and the least summer/spring and this may be attributed to the life cycle of the macro-invertebrate communities / NRF VLIR
30

Assessment of a hydrodynamic water quality model, DUFLOW, for a winter rainfall river

Nitsche, N. C. 12 1900 (has links)
Thesis (MEng)--Stellenbosch University, 2000. / ENGLISH ABSTRACT: The Berg River is one of the largest rivers in the winter rainfall area of the Western Cape and is one of the most important water supply sources of the area. The Riviersonderend-Berg system needs to be expanded in order to meet increasing water demands of the Greater Cape Town (GCT) region. The implementation of future schemes will remove additional fresh water from the Berg River main stem, which will give rise to increased nutrient levels and higher salinity in the water. A water quality information system (WQIS) has been proposed to benefit the management of water resources, the flow quantity and the quality of the water. A part of this WQIS will be a water-quality simulation model that characterizes the water quality situation and is able to predict water quality responses to future implementations, as well as simulate different scenarios that can be used for management purposes. The objective of this study is to represent the water quality situation of the Berg River in a simulation model by implementing, testing and verifying a water quality simulation model, and assembling a hydraulic and water quality database suitable to meet foregoing objectives. This study firstly examined the water quality variables of concern: pH, Total Dissolved Salts (TDS) and phosphates to develop an understanding of the water quality responses and causes of the main stem of the Berg River system. A thorough review of the available models has been undertaken in the light of certain selection criteria, before determining that DUFLOW would be an acceptable model for this study. The water quality variables that have been modelled are TDS, Phosphates as P04, Oxygen and Temperature. As no predefined module simulating temperature, TDS and COD was included; these algorithms, describing the processes of these water quality variables have been additionally coded. The coding was possible, as DUFLOW' s water quality module consists of an open structure. The predefined water quality module was simplified to only include the water quality process algorithms, for water quality variables where data was available. Unfortunately, phosphates were mainly simulated on advection, and the influence of all the additional processes could not be assessed. All data gathering and preparation for the model had to be completed before commencing the model configuration. This included information on cross-sections, historical flow records, bridges and weirs for the hydraulic component ofDUFLOW. For the water quality module, information on historical grab samples has been obtained and 'infilled' to provide daily time series. To simulate the water quality in a river as accurately as possible, the flow simulation needs to be accurate. Ungauged subcatchment runoff was added to the simulation model to improve the correspondence between the simulated and the measured flow. Calibration of the water quality part of DUFLOW was completed by adjusting the different parameters after a sensitivity analysis. The model was verified by using a different time period than for the configuration, to ensure that an independent data set has been used. After configuring, calibrating and verifying the model, the applicability of the model could be tested for different scenario runs. Three scenarios were chosen according to real situations: • a short term effluent spill, with and without water releases from an upstream source (either Skuifraam Dam or Voëlvlei Dam); • the impact on the flow and water quality situation of the river when an upstream dam is built; • a long term management control scenario, that analyses load or concentration releases into the river according to limitations upstream and downstream of the discharge location. The scenario analysis provides an opportunity to assess the applicability of DUFLOW to simulate real time management and operational issues in a river and to aid in management decisions. / AFRIKAANSE OPSOMMING: Die Bergrivier is een van die grootste riviere in die winterreënvalgebied van die Weskaap en is een van die mees belangrike waterverskaffingsbronne in die area. Die Riviersonderend-Bergrivier-stelsel moet uitgebrei word om aan die groeiende waterbehoefte van die groter Kaapse Metropolitaanse Area te voldoen. Die implementering van toekomstige skemas sal addisionele vars water uit die hoof-loop van die Bergrivier onttrek, wat tot hoër voedingstof-vlakke en soutgehalte in die water sal lei. 'n Waterkwaliteitsinformasiestelsel (WQIS) sal van nut wees om die vloei-omvang en waterkwaliteit van waterbronne te bestuur. 'n Deel van die WQIS sal 'n waterkwaliteit-simulasiemodel wees, wat die waterkwaliteitsituasie sal kan ontleed, waterkwaliteit-reaksies op toekomstige implementerings kan voorspel, asook verskeie scenarios vir bestuursdoeleindes kan simuleer. Hierdie studie behandel spesifiek die waterkwaliteitsveranderlikes pH, totale opgeloste soute, fosfate, temperatuur en suurstof om 'n begrip te ontwikkel van die waterkwaliteitsreaksies en oorsake van die hoofloop van die Bergriviersisteem. Die doelwit van hierdie studie is om die waterkwaliteitsituasie van die Bergrivier uit te beeld deur die implementering, toets en kalibrasie van 'n waterkwaliteit-simulasie model, asook die insameling van hidrouliese- en waterkwaliteitsdata om aan bogenoemde doelwitte te voldoen. 'n Reeks beskikbare modelle is deeglik ondersoek voordat besluit is dat die DUFLOW model 'n gepaste model vir hierdie spesifieke studie is. Die keuse was gebaseer op spesifieke vereistes wat as belangrik beskou is deur potensiële bestuursgeorienteerde gebruiksgroepe. Die waterkwaliteitsveranderlikes wat gemodelleer is, is totale opgeloste soute, fosfate as P04, suurstof en temperatuur. Omdat geen voorgegewe temperatuur-, TDS- en COD modules in die model ingesluit is nie, is die algoritmes wat die prosesse van hierdie waterkwaliteitsveranderlikes beskryf, addisioneel gekodeer. Die kodering is moontlik gemaak deur die oop struktuur van DUFLOW se waterkwaliteitsmodule. Die voorgegewe waterkwaliteitsmodule is vereenvoudig om alleenlik die waterkwaliteit proses-algoritmes in ag te neem wanneer data vir waterkwaliteitsveranderlikes beskikbaar was. Ongelukkig is die fosfate hoofsaaklik op beweging gesimuleer, en die invloed van alle addisionele prosesse kon nie getoets word nie. Alle data-insameling en -voorbereidings vir die model moes voltooi word, voordat begin kon word met die opstel van die simulasie-model. Dit het inligting oor dwarssnitte, historiese vloeirekords, brik en keerwalle vir die hidrouliese komponent van DUFLOW ingesluit. Vir die waterkwaliteitsmodule is inligting van historiese bemonstering verkry en ingevulom 'n daaglikse tydreeks te verkry. Om die water-kwaliteit van 'n rivier so akkuraat as moontlik te simuleer, moet die vloei-simulasie redelik akkuraat wees. Ongemete sub-opvanggebied afloop is bygetel om die korrelasie tussen die gesimuleerde en gemete vloei te verbeter. Kalibrasie van die waterkwaliteitmodule van DUFLOW is voltooi deur die verskillende parameters te verstel na 'n sensitiwiteits-analise. Die model is geverifieer deur 'n ander tydperiode as die vir die opstel te gebruik, om sodoende te verseker dat Inonafhanklike data stel gebruik word. Na die opstel, kalibrasie en verifiering van die model, kon dit toegepass word vir verskillende bestuursscenanos. Drie scenarios is na aanleiding van werklike situasies gekies: 'n korttermyn uitvloeisel storting-situasie met en sonder loslatings van 'n stroomop bron (Of Skuifraamdam Of Voëlvleidam), die impak op die vloei- en waterkwaliteitsituasie van die rivier sou 'n dam stroomop gebou word. 'n langtermyn bestuurs-scenario waarin die lading en konsentrasies, veroorsaak deur die loslatings vanuit die dam na die rivier, ontleed word na aanleiding van beperkings stroomop en -af van die loslatingsplek. Die analise van die scenarios verskaf 'n geleentheid om die toepaslikheid van DUFLOW te ondersoek om werklike operasionele aangeleenthede te simuleer en om sodoende bestuursbesluite te vergemaklik.

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