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Effects of St. Lucie Estuarine Discharge Water and Thermal Stress on the Coral Montastraea cavernosaUnknown Date (has links)
Coral reef declines, particularly in coastal zones, have been linked to thermal
stress and anthropogenic impacts on water quality. St. Lucie Reef near Stuart, Florida
receives increased estuarine efflux as a result of watershed changes and management
policies that have substantially altered historic, natural flows. This research used ambient
and elevated temperatures (25°C and 30°C, respectively), and offshore versus St. Lucie
Estuarine discharge water to investigate the individual and interactive effects of thermal
and water quality stress on Montastraea cavernosa, a dominant scleractinian coral
species at St. Lucie Reef. These goals were accomplished using ex-situ, factorial,
experimental design that was supplemented with existing in-situ monitoring on St. Lucie
Reef. Zooxanthellae density and chlorophyll content were evaluated to determine effects
on the corals and their symbionts. Zooxanthellae populations were significantly affected
by thermal stress. Significant interactions between temperature and water treatment were observed, suggesting that the impacts of discharge water may be supplanted when corals
are exposed to thermal stress. In a supplement to the experiment, M. cavernosa colonies
transplanted from Palm Beach to St. Lucie Reef demonstrated resilience despite exposure
to more variable environmental conditions. Collaborative partnerships with multiple state
agencies and local government offices facilitated data sharing to inform decision making
for South Florida’s resource management strategies. Creating effective resource
management is crucial for the conservation of coastal ecosystems impacted by land-based
sources of pollution both locally and globally. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection
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Assessment of the effects of environmental contaminants on feral fish populations in the Olifants river systemLebepe, Jeffrey January 2018 (has links)
Thesis (Ph.D (Zoology)) --University of Limpopo, 2018 / Freshwater ecosystems are the most threatened systems globally, suffering from channel modification, over extraction of water and, of particular concern, pollution. In South Africa, Olifants River is categorised as the third most polluted river system. Acid mine drainage seeping from derelict and abandoned mines has been described as the primary stressor in the upper Olifants catchment. The increase of metal concentration in the water, sediment and fish tissues has been evident over the past few decades. As a result, there has been an increasing concern regarding the effects of increased metal concentrations on the health of fish and the safety of communities consuming fish from the polluted Olifants River system. This study used enzymatic and histopathologic biomarkers to assess the physiological response of Oreochromis mossambicus and Labeo rosae to environmental contaminants. The study further investigated the metal accumulation trend of across different fish tissues and assessed the edibility of O. mossambicus and L. rosae from Loskop and Flag Boshielo dams. Water, sediment and fish samplings were carried out concurrently during low flow and high flow seasons in 2014. Water and sediment sampling were done at the inflow, middle and dam wall. A minimum of 10 fish specimens for each species were collected from Loskop and Flag Boshielo dams during each sampling. For bioaccumulation analysis, liver, gill and muscle tissues were dissected out, wrapped with aluminium foil and frozen. Frozen samples were sent to SANAS accredited laboratory for metal analysis. For Histopathology, tissues were fixed in 10% neutral buffered formalin prior processing. Tissue processing was done at the Pathology laboratory of the University of Pretoria, Onderstepoort campus. For biomarker analysis, liver and brain tissues were fixed in liquid nitrogen in the field and transferred to the -80°C biofreezer at the University of Limpopo, Biotechnology Unit laboratory. Metal concentrations in the muscle tissue were used to calculate hazard quotient for human health risk assessment which was based on the assumptions that an adult weighting 70 kg consume 150 g portion once per week. Alkaline pH was observed in the water throughout the study. Most water constituents were within the guidelines at both dams. The water at Flag Boshielo Dam was oligotrophic with Loskop Dam showing mesotrophic conditions. Concentrations were below detection level for most metals; however, significant concentrations were recorded in the bottom sediment. Although Loskop Dam is being described as a repository for pollutants from the upper Olifants catchment, no significant differences (p>0.05) were observed for metal concentrations in sediment between the two dams. Coinciding with sediment metal concentrations, liver, gills and muscle have shown notable concentrations for both species at Loskop and Flag Boshielo dams. The common trend of liver accumulating higher metal concentration followed by gill and muscle (liver>gills>muscle) was observed for most metals on O. mossambicus and L. rosae at both dams. In contrast, lead, strontium and manganese showed higher concentrations in the gills. Muscle exhibited lowest concentrations for most metals. Remarkable trends on the activities of biomarkers, lactate dehydrogenase (LDH), glucose-6-phosphate dehydrogenase (G6PDH), glutathione-S-transferase (GST) and acetylcholinesterase (AChE) were detected for both species at Loskop and Flag Boshielo dams. Labeo rosae population have shown a significantly high (p<0.05) LDH activities at Loskop Dam and no significant difference (p>0.05) was observed for Oreochromis mossambicus. Glucose-6-phosphate dehydrogenase activities exhibited no significant difference (p>0.05) for both species between the two dams. Labeo rosae have shown a significantly high (p<0.05) GST activities at Loskop Dam whereas Oreochromis mossambicus exhibited no significant difference (p>0.05) between the two dams. Acetylcholinesterase (AChE) has shown no significant difference (p>0.05) for both species between the Loskop and Flag Boshielo dams. LDH, G6PDH and GST activities have shown relationship with metal concentrations, which makes them good biomarkers of metal exposure.The condition factor indicated that overall conditions of O. mossambicus and L. rosae from Loskop and Flag Boshielo dams were good. Hepatosomatic index results were not conclusive. Most histopathological alterations were recorded on both species at both dams, but with different magnitude of severity. Regressive changes were more prominent in the liver and gills of both species at Loskop and Flag Boshielo dams followed by progressive change. Gills of Oreochromis mossambicus exhibited moderate modifications (score >20) at Loskop Dam and slight modification (score <20) at Flag Boshielo Dam. Labeo rosae populations have shown slight modifications (score <20) in the gills at both dams. Both species have shown significant difference (p<0.05) on the gill index between the two dams. Liver index has also exhibited significant difference (p<0.05) for each species between Loskop and Flag Boshielo dams. Slight modifications (score <20) were observed in the liver for both species at Loskop and Flag Boshielo dams. Both species have shown to accumulate metals within their tissues with liver accumulating higher concentration for most metals, followed by gills and muscle, respectively. Although muscle showed to accumulate lesser metal concentrations, it still raise a serious concern as it is the tissue consumed by human. Lead, chromium, cobalt and antimony concentrations have been the only metals of concern in this river system over the past few years; nevertheless, the present study has shown that other metals viz. arsenic, silver and selenium have exceeded international levels for safe consumption. Given the metal concentration trend reported over the past two decade in fish tissues, there is a need for urgent intervention to address the acid mine drainage problem to ensure sustainable development of the Olifants River and safety of communities depending on it for their livelihood. / NRFand RAD
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Pharmaceutical Waste in Vermont: Results from a Survey on Purchasing, Use & DisposalHart, Christine 01 January 2018 (has links)
Pharmaceutical waste is an emerging form of waste with significant impacts on the environment. This study reports the results of a state-wide phone survey on pharmaceutical purchasing, use and disposal behavior among Vermont residents (n = 421). The objectives of this study were: 1) to compare the demographic nature of populations who purchase and use medicaton to those associated with leftover medication, and 2) to evaluate the impact of disposal behavior in Vermont and to recommend strategies to minimize pollution. The findings of this study showed that approximately 93% of survey participants reported purchasing of medication, 60% reported leftover medication and 25% reported disposing of medications down-the-drain or via municipal trash, both of which are known pathways leading to environmental pollution. Results indicate that pharmaceutical waste is common in Vermont and that disposal behavior may be contributing towards pollution. The conclusion of this study is that better management of pharmaceutical waste is needed to protect the environment and public health.
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Analysis of water pollution control laws in South Africa : a comparative analysis of South Africa, India and the United KingdomNkosi, Busisiwe Rachel January 2015 (has links)
Thesis (LLM. (Development Management Law)) -- University of Limpopo, 2015 / Water is the source of life for human beings, animals and plants also need water for them to grow. The scourge of water pollution in our country due to various reasons is of great concerns and if left unattended will have dire consequences. Uncontrolled water pollution results in health hazards to human beings, animals and other living things. In terms of our Constitution the state as a custodian of all natural resources has a duty to ensure that water as a scarce resource is preserved for the present and future generations. Legislative measures are needed in order to ensure that same prevails. Legislation imposes measure such as a permit and its condition that must be respected by the holder of such permit. Failure to observe the condition of the permit is punishable by law for both corporates and human beings.
Most environmental crimes are caused not by a deliberate intention or negligence but by poor or ineffective management systems. Public education is important in ensuring that water pollution does not take place. Authorities must also be strict in ensuring compliance with permits and prevention of water pollution as prevention is better that cure. This dissertation examines water pollution legislation in South Africa, India and the United Kingdom and offers a comparative analysis and recommendations to South Africa. The three countries are developed and also allocated in three different continents. The examination and analysis of how they fight water pollution gives a chance to South Africa on how it may improve its legislation and maintain its water quality.
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Les attestations d'assainissement au Québec : des ententes environnementales avantageuses pour les industries ou l'environnement?DesMarchais, Pierre-Olivier January 2005 (has links)
No description available.
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Bioindication of air quality in forests of northern and central California using epiphytic macrolichen communitiesJovan, Sarah 19 May 2005 (has links)
Graduation date: 2005
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Aerobic biotransformation of chlorinated aliphatic hydrocarbons by a benzyl alcohol grown mixed culture : cometabolism, mechanisms, kinetics and modelingTejasen, Sarun 27 June 2003 (has links)
The aerobic transformation of TCE and cis-DCE by a tetrabutoxysilane-grown
microorganism (Vancheeswaran et al., 1999) led to the investigation of novel
substrates, including benzyl alcohol, for promoting cometabolism. The culture grew
on carboxylic compounds and alcohols, but did not grow on formate, methanol,
methane, propane, butane, ethylene, benzene, toluene, or p-xylene. Cis-DCE
transformation was observed when the culture grew on butyrate, glucose, 1-propanol,
1-butanol, ethanol, benzyl alcohol, and phenol, and effectively transformed TCE, cis-DCE, and vinyl chloride when grown on phenol or benzyl alcohol.
Several cycles of growth on benzyl alcohol led to increases in TCE
transformation rates and transformation capacities. Products of benzyl alcohol
degradation shifted from benzaldehyde to 2-hydroxy benzyl alcohol (2HBA) during
the several cycles of growth. In resting cells studies, 2HBA production rates were
highly correlated with TCE transformation rates. TCE transformation and 2HBA
production rates doubled when the culture was grown on phenol and rates of TCE
transformation were correlated with 2HBA production rates. Benzyl alcohol- and
phenol-grown cells oxidized toluene to o-cresol, which indicated the similarity
between benzyl alcohol ortho-monooxygenase, phenol hydroxylase, and toluene
ortho-monooxygenase. 2-Butyne and 1-hexyne (but not acetylene) inhibited benzyl
alcohol- and phenol-grown cells similarly, indicating the same ortho-monooxygenase
was responsible for TCE cometabolism.
Resting cell kinetic studies were performed with cells grown on phenol or
benzyl alcohol. Benzyl alcohol degradation followed a Monod kinetics while phenol
degradation followed a Haldane kinetics. The maximum transformation rates (k[subscript max]) of
TCE, cis-DCE, and VC achieved by phenol-grown cells were about a factor of two
higher than achieved with benzyl alcohol-grown cells, while the half-saturation
constants (K[subscript s]) were in a similar range. Transformation capacities (Tc) for TCE, cis-DCE, and VC were about a factor of two to four higher with phenol-grown cells. The
modeling of TCE, cis-DCE, and VC transformation using independently measured
k[subscript max] and K[subscript s] values matched well with observed data from batch tests. Benzyl alcohol
was shown to be an effective novel substrate for the aerobic cometabolism of TCE,
cis-DCE, and vinyl chloride. Being a non-regulated compound, it might have
applications for in-situ bioremediation. / Graduation date: 2004
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Molecular biomarker hydrocarbons as discriminant indicators of environmental pollution - characterization and sourcesAboul-Kassim, Tarek A.T. 10 May 1994 (has links)
Graduation date: 1995
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La pollution industrielle de la Moselle française naissance, développement et gestion d'un problème environnemental, 1850-2000 /Garcier, Romain Bravard, Jean-Paul January 2005 (has links)
Reproduction de : Thèse de doctorat : Géographie et aménagement : Lyon 2 : 2005. / Titre provenant de l'écran-titre. Bibliogr.. Index.
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Contamination by lead and other trace metals in roadside soil and vegetation in Hong Kong /Tai, Keen-man. January 1982 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1983.
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