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Land-use on water quality of the Bottelary River in Cape Town, Western CapeItoba Tombo, Elie Fereche January 2010 (has links)
Thesis (MTech (Environmental Management))--Cape Peninsula University of Technology, 2010 / Freshwater scarcity and river pollution has become a serious challenge for governments
and scientists. Worldwide, governments have a responsibility to provide their populations
with enough clean water for their domestic needs. Scientists will have an enormous task
to find a way to purify polluted water, because of its vital role in human lives and an
increasing demand for water consumption due to population growth. Although the water
from the Bottelary River is used on a daily basis for farming activities, its pollution level
as well as spatial distribution of effluents in the catchment is unknown. In the present
study, I took monthly water samples from six sampling points for laboratory analysis.
The laboratory determined concentration levels of phosphorous, chloride, nitrate, and
nitrate nitrogen (N03N), as well as the chemical oxygen demand (COD) and suspended
solids from the samples. On the same occasion's pH, dissolved oxygen, electrical
conductivity and temperature were measured in-situ using a multi-parameter reader. The
results were then compared with the South African Water Quality Guidelines for Aquatic
Ecosystems and for irrigation (DWAF, 1996a, 1996c). The non-point pollution source
(NPS) model was used to generate predictions of the pollution level from the land-uses
and use the data obtained from the field to validate the model predictions. Finally, I
performed a two-factorial A One-way Analysis of Variance (ANOVA) without
replication to assess the spatial and temporal variation of the measured variables along
the river.
The findings of the study have shown that the concentration levels of some compounds
are below the Target Water Quality Range (TWQR) set by the Department of Water
Affairs and Forestry (DWAF, 1996a, 1996b, 1996c) while, the concentrations of chloride,
total nitrogen and water quality variables such as electrical conductivity, suspended
solids, are higher than the TWQR (DWAF, 1996a, 1996b, 1996c). Based on the above
findings water of the Bottelary River can have negative effects on the environment and
human lives because of the concentration level of these compounds. It was therefore
recommended that, environmentally friendly measures and practices must be undertaken
in order to decrease the pollution and avoid further pollution of the river.
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Exploring potential impacts of hydraulic fracturing (fracking) on groundwater contamination in the Karoo: perspectives on institutional capabilities in water management in South AfricaChisebe, Khumbelo Britney January 2017 (has links)
A dissertation submitted in fulfilment of the requirements for the degree of
Master of Environmental Science.
with
Witwatersrand University, Johannesburg, South Africa,
(School of Geography, Archaeological and Environmental Science within the
Faculty of Science)
2nd June 2017. / Hydraulic fracturing in the Karoo is said to be a game changer of energy sector in South Africa, but it is said to pose potential groundwater contamination. Therefore the aim of the study was to investigate the extent to which current institutional set up in South Africa can deal and address potential environmental challenges that are associated to fracking. The study was particularly interested in investigating the institutional capabilities in the context of water management.
The literature review of this study showed that water resource is a major environmental concern that revolves around hydraulic fracturing, including the water resources use and potential contamination. In addition, it should be considered that hydraulic fracturing is a new mining process in South Africa and Africa as a whole with controversial mining techniques and environmental impacts involved within this process. The review indicates that the biggest issue with proposed hydraulic fracking mining process in the Karoo is if the South African Government has taken into consideration the resources, infrastructures and skills to execute the process successfully. The literature asserts that even if proper enforcement of any regulations on this rapidly expanding industry will still be difficult as the regulation is insufficient due to certain explicit exemptions. In South Africa, the starting point for hydraulic fracturing and the associated regulations that governs fracking, is the recognition of an argument that South Africa does not possess any fracking specific laws, guidelines or even polices.
Research participants were asked to give their views on the research topic by answering the semi structured interview questions. Data from the semi-structured interviews and literature review was analysed and discussed to address the research questions. The results of the investigation confirmed that there was no any legislation in place to govern this mining process in South Africa. Currently there are legislations which are under review and development to also address hydraulic fracking and the protection of water resources. The government should also involve other research institutes in the drafting and decision making of the legal institute governing hydraulic fracking to ensure that all gaps are identified before fracking can be permitted in the Karoo. / MT 2017
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An assessment of the impact of the black village communities, their associated land-use and related practices on water quality of the Kat River in the Eastern Cape, South AfricaSoviti, Malixole Knottien 16 May 2013 (has links)
Amongst others, the South African National Water Act No. 36 of 1998 acknowledges that access to sufficient safe and clean water is a basic right to all South Africans. However, it is well known that millions of inhabitants of rural communities in South Africa are still deprived of this right. Many rural communities in South Africa are thus consuming unsafe, untreated water everyday, thereby exposing themselves to waterborne diseases. The main reason of concern however is the fact that, nevertheless, little is known about rural water quality in South Africa as most water quality work is being undertaken in urban areas. The study's aim is twofold: first, the study examines the impact of Black rural communities' land-use and related activities on water quality and second is specifically, to study the washing practices of the rural communities in the upper Kat River area. To understand the potential impacts of the upper Kat River Black village communities and their associated land-use practices on the quality of upper Kat River catchment, prominent land-use and related activities in the area were investigated. Study area maps were studied and field surveys undertaken to observe major land-use and related activities in the area. The results of the study show that most used land in the area is being utilised for agricultural activities. Settlements and commercial forestry also occupy considerable areas of land. The literature survey suggests that such land-use could have a considerable degrading impact on the quality of both surface and groundwater. The study also investigated the impact of the in-stream use of detergents on water quality in the upper Kat River valley, Eastern Cape - South Africa. In-stream washing practices of certain communities in the upper Kat River valley were investigated and the impact of detergents on water quality was assessed. Recovery of the flow from the input of detergents was also measured. During the study, it has been ascertained that doing laundry by the stream is the common practice in the study area. Water quality analysis results show a remarkable increase on the levels of chloride, turbidity, and electrical conductivity in water as a consequence of direct input of detergents practice into the river during the washing. The recovery of the water quality at a distance of 1km from site of input was almost complete. Water quality monitoring programme was undertaken to establish a link between land-use and the quality of water. In a water quality study routine carried out for a period of 40 weeks on a twice monthly frequency, the state of the flows of the river was determined; water samples were collected at pre-determined points; and the in situ analysis of selected water quality variables (with the exception of the faecal coliforms whose analysis was carried out in the biotechnology laboratory) was carried out. Results of the study showed that the concentration of the studied water quality variables in the area varied widely with time. A clear distinction in concentration of variables such as electrical conductivity, turbidity, pH, total hardness, chloride, and nitrate was evident at the high compared to the low flow period of the study. The concentration of the studied water quality variables in the upper Kat River catchment area also seemed to vary over space. The concentration of variables such as electrical conductivity, pH, total hardness, chloride, nitrate, potassium, number of faecal coliform bacteria per 100ml was observed to be higher in most of the tributary streams than the main river. Turbidity however was orders of magnitude higher in the Kat River than the rest of the tributaries. Most importantly however, results of the study showed that there is a strong link between the quality of water and land-use and related activities in the area. The spatial results of the study showed a strong connection between some land-use and the concentrations of water quality variables. For example, areas of intense grazing were noted with high concentrations of nutrients like nitrate and a higher number of faecal coliform bacteria per 100 ml of water. It was established during the study that land-use and related activities in the upper Kat River valley are negatively impacting on the quality of water thereby rendering it less fit for use for domestic purposes. The continued use of the polluted water by the communities is thus accompanied by a danger of the outbreak of waterborne diseases like cholera. When the concerned communities met in a workshop to discuss the issue of quality of their water, they committed themselves to: • shunning water polluting activities, • at least boiling their drinking water before consuming it. The communities also requested a meeting with the Department of Water and Forestry officials to request a treated, piped supply of water. / KMBT_363 / Adobe Acrobat 9.54 Paper Capture Plug-in
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Development of a sediment quality triad approach to evaluate sediments in marine and freshwater environments of South AfricaShaddock, Bridget Florence 15 July 2014 (has links)
Ph.D. (Aquatic Health) / Please refer to full text to view abstract
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Pollution control investment decisions and policy preferences of senior managers of the Southern African fish processing industryLipschitz, Steven January 1990 (has links)
Bibliography: pages 134-147. / Pollution control regulations directed at the land-based factories of the Southern African fish processing industry do not appear to promote the required level of investment in pollution control systems. Two self-administered mail-questionnaires comprising undisguised fixed-alternative and open-ended questions were constructed to survey the opinions and viewpoints of a census consisting of twenty-seven senior managers responsible for making pollution control investments in the demersal and pelagic sectors of the fish processing industry. The first questionnaire was directed at establishing the relative importance of factors that influence waste and pollution control investment decisions as well as the perceptions and preferences of managers with regard to various pollution control policy options. Descriptive statistics such as the modal class were used to summarize the distribution of opinions and viewpoints within the research population. Rank ordered preference data was analyzed using a multidimensional unfolding computer algorithm. This structural multivariate statistical method is a special case of non-metric multidimensional scaling that generates perceptual maps which can aid in the discovery of the hidden structure underlying multidimensional decisions. Investments in waste and pollution control do not appear to have a high priority when compared to other strategic investments that the fish processing industry managers may make. The relative importance of factors that could influence the managers of the industry to invest in waste control equipment appear to be determined by the perceived financial returns that can be expected from such investments. Findings suggest that pollution control legislation is rendered ineffective due to inadequate enforcement. However, it appears that existing legislation needs to be rationalized in order to facilitate compliance. The most favoured pollution control instruments were those that lowered the cost of legally mandated expenses such as subsidies and income tax allowances. These were followed by permit systems which specified the allowable characteristics of discharges while allowing individual companies freedom of choice as to the method of achieving compliance. The second questionnaire was used to verify the researcher's interpretation of the findings and preliminary conclusions drawn from the replies to the first questionnaire.
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The use of biological indicators in assessing pollution status in selected rivers in Limpopo Province, South AfricaNephale, Livhuwani Eva January 2020 (has links)
Thesis (M.Sc. (Aquaculture)) -- University of Limpopo, 2020 / The aim of the study was to assess the extent to which biological indicators and biomarkers can be used to monitor the pollution status of the Sand and Blood Rivers. Physico-chemical parameters were assessed as a primary approach in assessing pollution status of the Sand and Blood Rivers. Temperature, pH, dissolved oxygen (DO), biological oxygen demand (BOD), turbidity, total dissolved solids (TDS), total nitrogen, phosphorus and ammonia were assessed during the rainy and dry seasons. Physico-chemical parameters showed spatial and temporal variation. The hierarchical average linkage cluster analysis grouped the reference sites (S1 and B1) into one group and sites after points of discharge (B2, S2, S3, S4 and S5) into another group. This grouping was due to the pollution status of each site, with the reference sites less polluted than the sites downstream of the wastewater treatment plant effluent points of discharge. The canadian council of ministers of the environment water quality index (CCME WQI) categorized reference sites as good, whilst sites after points of discharge were categorized as poor. This shows that the Sand and Blood Rivers are degrading.
Heavy metal contamination in water, sediment and grass from the Sand and Blood Rivers was evaluated during the rainy season and dry season. All assessed heavy metals (Cadmium, Chromium, Copper, Iron, Lead, Manganese, Nickel, and Zinc) were below the detection limit in water, with an exception for Iron and Manganese. All metals assessed were also below the probable effect levels (PEL) according to the CCME. Geo-accumulation Index showed that the Sand and Blood Rivers were not contaminated with heavy metals. The enrichment factor (EF) further showed that only site B2 was enriched with manganese from anthropogenic activities. Heavy metal assessment in Cyperus exaltatus showed that this grass is a poor candidate for phytoremediation.
Macroinvertebrates were used as biological indicators to assess pollution status of the Sand and Blood Rivers. Macroinvertebrates were sampled according to South African scoring system (SASS) and identified using aquatic invertebrates of South African rivers field guide. The SASS and average score per taxon (ASPT) categorized all sampling sites as critically modified. The family-level biotic index (FBI) also showed that the Sand and
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Blood Rivers are enriched with organic pollution. The reference sites recorded high macroinvertebrates diversity, compared to the sites after points of discharge. All indices used showed spatial and temporal variation in the water quality of the Sand and Blood Rivers. The relationship between macroinvertebrates and physico-chemical parameters were explored with the use of canonical correspondence analysis (CCA). The CCA triplots showed that the reference sites were associated with pollution sensitive taxa, whilst pollution tolerant taxa were associated with sites after points of discharge. Moreover, sites after points of discharge strongly correlated with phosphorus, nitrogen, ammonia, BOD and TDS.
Clarias gariepinus gills and liver histology were used as biomarkers in assessing pollution status in the Sand and Blood Rivers. Gills and liver samples were qualitatively and semi-quantitatively assessed. Fish from the reference sites had less gill lesions than fish from sites downstream. Alterations such as hyperplasia of interlamellar, fusion of secondary lamellae, epithelial lifting and hyperplasia of secondary lamellae were observed in fish collected from downstream. Fish from downstream also showed more liver alterations than fish from the reference sites. Alterations such as melano-macrophage centers (MMC), macrovesicular steatosis, sinusoid congested with kupffer cells, nuclei pleomorphism and vacuolation were identified in liver of fish from sites S4 and S5. This was further confirmed by the high gill and liver indices of fish from downstream.
Acetylcholinesterase enzyme (AChE) enzyme in brain and lactate dehydrogenase (LDH) in liver of Clarias gariepinus were used as biomarkers in assessing pollution status of the Sand and Blood Rivers. Both AChE and LDH enzymes were lower on fish from downstream compared to fish from the reference sites. This shows that AChE and LDH enzymes on fish from downstream were inhibited. This was attributed to the use of pesticides on farms surrounding the Sand and Blood Rivers and also the discharge of poorly treated sewage effluent from the Polokwane and Seshego wastewater treatment plants (WWTP’s). The Sand and Blood Rivers are surrounded by farms that utilize pesticides in their practice. This study showed that biological indicators and biomarkers can be used to assess pollution status of the Sand and Blood Rivers. However, biological
vii
indicators and biomarkers should be used in concurrence with physico-chemical parameters. / Department of Agriculture Forestry and Fisheries,
Water Research Commission (WRC)
and Aquaculture Research Unit.
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Biological monitorings of mining pollution in tributaries of the Olifants River in the Sekhukhune AreaMakwarela, Maanda January 2020 (has links)
Thesis (M.Sc. (Zoology)) -- University of Limpopo, 2020 / Water pollution has been one of the major concerns all over the world for at least the
past two decades. In South Africa, the Olifants River System is one of the most polluted
river systems. Anthropogenic activities being carried out within the Olifants River
Catchment area pose threats to the aquatic ecosystem. The Upper and Middle
catchments are being characterised by intensive mining, industries, agricultural
practices and inadequate sewage treatments. Thus, the aim of this study was to
investigate the influence of mining activities on the water quality and health status of the
Steelpoort River, a tributary of the Olifants River System. This was achieved through
assessing the quality of water by analysing physico-chemical parameters, macro nutrients and metals at four selected sites, determining the response of macro invertebrate assemblages to water quality using the South African Scoring System
(SASS) version 5 and determining the diversity of fish using the Fish Response
Assessment Index (FRAI).
Sampling of water, sediment, macro-invertebrates and fish was done seasonally
(August 2017 – May 2018) at four selected sites. Site 1 and site 2 were located upstream
while site 3 and site 4 were located midstream and downstream respectively. Water and
sediment samples were analysed by WATERLAB (PTY) LTD by means of Inductively
Coupled Plasma Optical Spectrometry (ICP-OES). Macro-invertebrates were sampled
following the SASS protocol. Macro-invertebrates were identified, counted and recorded
then released back to the river. Fish were sampled following the FRAI index protocol.
The results obtained indicated that the system variables; pH, water temperature,
dissolved oxygen and total dissolved solids fell within the target water quality range
(TWQR) for aquatic ecosystems. However, some concentrations of macro-nutrients
recorded were above the TWQR. These include ammonium at site 3 and nitrogen at
sites 2, 3 and 4 which indicated that there was a variation in the influx of macro-nutrients
into the river at different river sections. The higher concentrations of ammonium and
nitrogen may adversely affect the functioning and survival of biological communities.
The metal results indicated that most metals (As, B, Ba, Cd, Cu, Pb, Ni and Cr) fell within
the recommended water and sediment quality guidelines (DWAF 1996c; CCME 2012).
Chromium concentrations recorded in sediment were above the sediment quality
guideline at all the selected sites (CCME 2012). Iron and Zn were also above the
guideline values at all selected sites. In terms of physico-chemical parameters and metal
concentrations indicated that the water quality of the Steelpoort River was fairly good.
The macro-invertebrates were also analysed; their abundance, distribution and family
richness indicated that there was a deterioration of water quality from upstream to
downstream which may be an indication of increase in influx of pollutants and
modifications in the stream such as flow, cover and microhabitat. The highest macro invertebrate abundance and richness was at site 1 while the lowest was at sites 3 and
4. Site 3 was highly modified while site 1 was the least modified site. The
Ephemeroptera, Plecoptera and Trichoptera index (EPT) and Ephemeroptera,
Plecoptera and Trichoptera/Chironomidae ratio (EPT/C ratio) analysis also confirmed
that the water quality of the Steelpoort River is deteriorating from upstream to
downstream. Site 1 had the highest value of EPT while site 2 had the highest value of
EPT/C. Site 3 had the lowest value for both EPT and EPT/C ratio. The higher EPT and
EPT/C ratio indicate the presence of highly sensitive taxa. The Canonical
Correspondence Analysis (CCA) indicated a strong correlation between metals (Pb, Cr,
Mg, As and Se) and macro-invertebrates (Pleidae, Ecnomidae, Athericidae,
Synlestidae, Lestidae and Pyralidae). The SASS 5 results also indicated deterioration
of water quality from upstream to downstream with the highest values of SASS score
and Average Score Per Taxon (ASPT) being recorded at site 1 followed by site 2 while
the lowest SASS score and ASPT were at site 3 followed by site 4.
The use of fish as biological indicator also supported the same pattern of water quality
deterioration and influx of pollutants which was previously indicated as increasing from
upstream to downstream of the Steelpoort River. Site 1 had the highest fish abundance,
while site 4 had the lowest fish abundance. However, the fish species richness was
highest at site 4 while the lowest species richness was at site 1. The Shannon Weiner
Diversity Index also supported that site 4 had the highest fish species richness while site
1 had the lowest species richness. The FRAI results indicated that different sites were
in different Ecological Categories (EC). The ECs showed a trend from higher EC
category upstream to lower EC category downstream. Site 1 had an EC of C followed
by site 2 with an EC of C/D, site 4 with EC of D and then site 3 with the lowest EC of
D/E. This might serve as an indication of decrease in habitat availability, increase of
pollutants input and increase in stream modification. The CCA showed a weak
correlation system variables and fish species. However, a strong correlation was observed between most metals and most fish species with the exception of Mesobola
brevianalis Boulenger, 1908, Chiloglanis pretoriae Van Der Horst, 1931, Labeobarbus
marequensis Smith, 1841 and Enteromius neefi (Greenwood, 1962).
In conclusion, the water in the Steelpoort River is still in relatively good condition.
However, increasing mining, industrial and agricultural practices in the catchment area
results in increase of pollutants input into the river system. All the four selected sites
were contaminated to some degree, with site 3 being the most affected site and site 1
being the least affected site. For this reason, it is important to continuously monitor the
health status of the Steelpoort River and to educate the nearby communities who rely
on this river for water supply about the quality of the water from the Steelpoort River. / DSI-NRF SARCHI (Ecosystem Health)
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The remediation of surface water contamination: WonderfonteinspruitOpperman, Ilze 29 February 2008 (has links)
When mining activities in some parts of the Witwatersrand were discontinued in
2000, the defunct workings started to flood. In September 2002 the mine water
started to decant from the West Rand Mine Basin (WRB) next to the Tweelopie East
Stream. Treated water is currently used in the mine's metallurgical plants and 15Ml
per day of treated water is disposed firstly into the Cooke Attenuation Dam and then
discharged into the Wonderfonteinspruit.
The aim of this study was to find and provide remediation measures as a result of
acid mine drainage and other impacting factors on the water quality and volume in
the Wonderfonteinspruit.
Conductivity and total dissolved solids (TDS) were highest at the point where the
tailings dam leached into the Wonderfonteinspruit. Sulphate was very high as was
expected due to acid mine drainage. The best way to treat the high sulphate levels is
with sulphate-reducing bacteria. To avoid the fatal flaw of many other constructed
wetlands, a continuous carbon source is provided to the bacteria in the form of
activated sewage from the Flip Human sewage treatment plant. Iron and other heavy
metals are being precipitated through oxidation reactions to form oxides and
hydroxides from the aerobic cell in the wetland. The wetlands are also known for
their ability to reduce nitrate and microbial values with great success.
In the remediation, four elements that currently do not comply with the SABS criteria
for class 0 water, were chosen for improvement: conductivity, dissolved solids,
sulphate and iron. Conductivity falls within class 1 and has a maximum of 178 mS/m
@25ºC that should be reduced to under 70 mS/m. Total dissolved solids have a
value of 1585 mg/l, which is much higher than the prescribed 450 ml/l, making it
class 2 water. The last two problematic elements are both considered as class 2
water: sulphate peaks at 592 mg/l where the preferred value is 200 mg/l, and iron
should be 0.01 mg/l, not the staggering 0.3mg/l.
iv
Alternative mitigation methods were identified and analysed for the impacts of the
five major contaminators and ultimately the solution comes down to constructed
wetlands. This is not a straightforward solution, however, and a specific design to
accommodate all the different pollutants and water quality ranges was proposed.
The other mitigation methods include a cut-off trench and pump-back system for the
tailings dam, as well as the implementation of a monitoring programme. The sewage
works should be optimised and better managed. Both the settlement and agricultural
sector need to be educated on their representative impacts on the environment and
government assistance should be available. / ENVIRONMENTAL SCIENCES / MSC (ENVIRON MANAGEMENT)
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Optimisation of HPLC-based methods for the separation and detection of herbicide glyphosate and its major metabolite in waterMadikizela, Lawrence Mzukisi January 2010 (has links)
Dissertation submitted in partial compliance with the requirements for the Masters Degree in Technology, 2010. / Water storage dams play an important part in the collection and purification of water destined
for human consumption. However, the nutrient rich silt in these dams promotes rapid growth
of aquatic plants which tend to block out light and air. Glyphosate is universally used as the
effective non-selective herbicide for the control of aquatic plants in rivers and dams.
Invariably there is residual glyphosate present in water after spraying of dams and rivers with
glyphosate herbicide. The amount of residual glyphosate is difficult to determine on account
of high solubility of glyphosate in water. Thus a method of sample preparation and a sensitive
HPLC method for the detection of trace amounts of glyphosate and its major metabolite
aminomethylphosphonic acid (AMPA) in water is required. A crucial step in sample
preparation is pre-column derivitization of glyphosate with 9-fluorenylmethyl chloroformate
(FMOC-Cl).
For sample pretreatment, water samples were derivatized with FMOC-Cl at pH 9, extracted
with ethyl acetate and sample clean-up was carried out by passing a sample through the SPE
cartridge. For SPE, recovery studies were done to choose a suitable cartridge for glyphosate
and AMPA analysis. The following cartridges were compared, namely, C18, Oasis HLB and
Oasis MAX SPE cartridges. Best recoveries (101% for glyphosate and 90% for AMPA) were
obtained using 500 mg of C18 solid-phase extraction cartridge. The eluent from SPE cartridge
was injected into HPLC column. Three types of separation columns (namely; C18 column,
silica based amino column and polymeric amino column) were compared for the separation
of glyphosate and AMPA. The best separation of glyphosate and AMPA in water samples
was achieved using a polymeric amino column and a mobile phase at pH 10 which contained
a mixture of acetonitrile and 0.05 M phosphate buffer (pH 10) 55:45, (v/v) respectively.
The method was validated by spiking tap water , deionized water and river water at a level of
100 μg/l. Recoveries were in the range of 77% -111% for both analytes. The method was also
used in determining the levels of glyphosate and AMPA in environmental samples. This
method gave detection limits of 3.2 μg/l and 0.23 μg/l for glyphosate and AMPA
respectively. The limits of quantification obtained for this method were 10.5 μg/l and 3.2 μg/l
for glyphosate and AMPA respectively. / Eskom Tertiary Education Support Programme (TESP) Durban University of Technology.
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'n Ekologiese studie van Germistonmeer : met spesiale verwysing na besoedelingstoestande en die effek daarvan op die akwatiese makrotebraatfauna10 September 2015 (has links)
M.Sc. / Please refer to full text to view abstract
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