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For the benefit of current and future generations : prospects for intergenerational equity in South AfricaLittleford, Sarah-Jane January 2014 (has links)
This thesis examines a crisis of governance in the Republic of South Africa (RSA), a crisis which threatens Constitutionally guaranteed intergenerational rights to water, meaning these rights are unlikely to be upheld. RSA's post-1994 Constitution incorporated a number of historically unparalleled human rights, based on fundamental principles of human dignity and equality. This includes the right to water resources for current and future generations - making RSA one of a few countries to enshrine intergenerational rights in law. Under law, Government acts as fiduciary trustee with duties to protect the water resources for current and future generations of citizens. The thesis asserts that influences of Emmanuel Kant, John Rawls and Edith Brown Weiss are reflected in the Constitution and subsequent laws. However, historical and on-going impacts from extractive industries in the province of Gauteng are negatively impacting upon intergenerational water rights. Acid mine drainage is an acidic wastewater produced as a by-product of mineral extraction - particularly gold. It is polluting ground- and surface-waters across the province. A lack of effective government response to this issue has meant that AMD is acting as a catalyst accelerating the country's already problematic governance processes to a crisis level. As it has no long-term management plan, the government is neglecting its intergenerational responsibilities and abrogating Constitutional purpose. This situation is exacerbated by multiple, often conflicting, understandings in different sectors of society of the significance of intergenerational equity, further reinforcing the governance crisis. Due to lack of government response, non-State agents, specifically the mining and financial sectors, are becoming increasingly involved in political decision-making and governance. This has positive short-term effects in ensuring that the rights of communities that were previously affected by water shortages and pollution are upheld. Yet there are potential serious long-term repercussions for democracy in RSA as a result: non-State actors are not best equipped to determine outcomes of governance, and this may result in procedures of deliberative democracy being contravened. Robert Dahl's theories inform this thesis's understanding of deliberative democracy. Consequently, although RSA's Constitution guarantees intergenerational equity in theory, it is hard to achieve in practice. This is due to the governance crisis that has been precipitated by acid mine drainage, so that intergenerational rights to water are an unlikely long-term outcome for this developing nation.
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Contamination levels in and cellular responses of intertidal invertebrates as biomarkers of toxic stress caused by heavy metal contamination in False BayMdzeke, Naomi Patience 03 1900 (has links)
Thesis (PhD) -- Stellenbosch University, 2004. / ENGLISH ABSTRACT:Heavy metals are persistent environmental contaminants whose sources of inputs into
the environment are both natural and anthropogenic. The levels of heavy metals
(cadmium, copper, nickel, lead and zinc) in the False Bay intertidal zone were
measured in the water, sediments and invertebrate species between August 2000 and
August 2001. The results of the water and sediment analyses revealed that most
pollution was associated with the northern shore of the bay between Strand and
Muizenberg, where the most populated and industrial catchments occur. Significant
spatial variations occurred, indicating the presence of localised contamination, while
seasonal variations may be related to changes in precipitation and runoff at different
times of the year. The concentrations of cadmium, nickel and lead were occasionally
higher than the levels recommended by the South African Water Quality Standards.
The possible sources of pollution at the different sites are also discussed. The
concentrations of the five metals in the different invertebrate species (Oxystele
tigrina, 0. sinensis, Choromytilus meridionalis, Patella oculus, Patiriella exigua and
Tetraclita serrata) also revealed significant seasonal and spatial variations, with both
the soft tissues and shells accumulating heavy metals. The barnacle T serrata from
Rooiels had the highest cadmium concentration (70.67 J.lg/g dry weight), which may
be related to historic pollution inputs from the military activities which took place at a
weapons testing site at this site between 1987 and 1994, although no evidence was
found to confirm this. The periwinkle 0. tigrina from Strand had the highest copper
concentration (70.25 J.lg/g) while the limpet P. oculus from the same site had the
highest nickel concentration (35.75 J.lg/g). The shells of the mussel C. meridionalis
from Muizenberg had the highest concentration of lead (25.75 J.lg/g). Since cadmium
occurs as a constituent of phosphate fertilisers used widely in the False Bay
catchments, the effects of cadmium exposure on the different species were
investigated during 14-day laboratory exposures to 200 and 400 J.lg/LCdCh. The
results revealed a general pattern of tissue metal increase in the exposed organisms,
followed by slight reductions after decontamination in clean seawater. The viscera
and kidneys of C. meridionalis accumulated most of the dissolved cadmium. The
shells of the mussels also accumulated cadmium, indicating the possible use of shells
as a detoxification matrix. / AFRIKAANSE OPSOMMING:Swaarmetale is persisterende omgewingskontaminante waarvan die insetbronne beide
natuurlik of van menslike oorsprong kan wees. Die kontaminasievlakke van
swaarmetale (kadmium, koper, nikkel, lood en sink) in die Valsbaai tussengetysone is
in die water, sedimente en invertebraatspesies bepaal vanaf Augustus 2000 tot
Augustus 2001. Voorlopige resultate van die water- en sedimentontledings het getoon
dat die meeste besoedeling by die noordelikke oewer van die baai voorgekom het
tussen Strand and Muizenberg, waar die mees digbewoonde en ge-industrialiseerde
opvangsgebiede is. Betekenisvolle ruimtelike en seisoenale variasie het in die
konsentrasies van swaarmetale voorgekom, met die ruimtelike variasie wat moontlik
gelokaliseerde kontaminasie aandui terwyl die seisoenale variasies weer verband mag
hou met veranderings in die neerslag en afloop gedurende verskillende tye van die
jaar. Die konsentrasie van kadmium, nikkel en lood was somtyds hoer as die vlakke
wat deur die Suid-Afrikaanse Waterkwaliteitsstandaarde voorgestel word. Die
moontlike bronne van besoedeling in die verskillende areas is ook in bespreking
genoem. Die konsentrasies van die vyf swaametale in die verskillende
invertebraatspesies (Oxystele tigrina, 0. sinensis, Choromytilus meridionalis, Patella
oculus, Patiriella exigua and Tetraclita serrata) het ook seisoenale en ruimtelike
variasies vertoon, die swaarmetale het in die sagte weefsel en skulpe van die
invertebrate geakkumuleer. Die hoogste gemiddelde konsentrasie van kadmium
(70.67 ).lg/g droe massa) is in die heel-liggaam monsters van die eendemossel T
serrata gemeet wat by Rooiels versamel is. Die vlakke mag verband hou met die
oprigting en aktiwiteite van die wapentoetsingsaanleg in die opvanggebied van die
Rooiels lokaliteit tussen 1987 en 1994, maar geen bewyse daarvan is gevind nie. Die
tolletjie, 0. tigrina wat in die 10kaliteit by Strand versamel is het die hoogste
gemiddelde konsentrasie koper gehad 70.25 pig droe massa), terwyl die klipmossel
P. oculus by dieselfde versamelpunt die hoogste konsentrasie nikkel (35.75 ).lg/gdroe
massa) gehad het. Eksperimentele studies is ook uitgevoer op vier invertebraat
spesies wat vir 14 dae in akwaria blootgestel is aan see-water met 200 en 400 p,g/L
CdCh, en daama gedekontamineer is in skoon seewater. / The NRF and the University of Stellenbosch, for funding this study.
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Anthropocentric impacts on the ecology and biodiversity of the Natalspruit watercourse and its associated wetlandsKruger-Franck, Elmarie 07 1900 (has links)
Information regarding the ecological wellbeing of the Natalspruit and its adjoining wetlands is
essential if the river is being managed using sound ecological management principles. Despite
this, little is known about this river, with little documentation at the regional or municipal level.
This study partially addresses this knowledge gap by evaluating the impacts of human activity
on a section of the Natalspruit and its adjoining wetlands. It reports on pollution concentrations
found at selected sample sites and compares the results to Rand Water data and the National
Standards and Guidelines of South Africa for physicochemical parameters and contaminated
soils. Water samples were collected at five chosen sample sites during May and July 2018. Soil
samples were taken during July 2018. The study found that water at all five sample sites is not
suitable for drinking, the health of livestock and recreational use due to the present and high
Total Coliform levels (ranging from 450 CFU/100ml to 100 000 CFU/100ml), as well as
Turbidity, Total Hardness, TDS, Mg, NO2, SO4, and BOD which also exceeded the guidelines.
Only site SS1 (May) exceeded the CaCO3 concentrations regarding livestock health. No
guidelines were available for DO levels on the health of livestock. Cl levels in the Natalspruit
was suitable for drinking. PO4 concentration at all the sites were all within the guidelines of
acceptable levels for aquatic ecosystems. In terms of heavy metals, Cr levels significantly
exceeded the guidelines at all five sample sites with the exception of ecosystem health. This is
of great concern due to the toxicity of Cr. Cu concentrations exceeded the guidelines for both
all land-uses protective of water resources and ecosystem health, at SS1, SS2, SS3 and SS5. Ni
concentrations exceeded the guidelines for all land-uses protective of the water resources at
SS5. Pb and Zn concentrations exceeded the guidelines for the land-uses protective of the water
resources at all the sites with the exception of SS4 for Pb and SS2 and SS4. SS1 and SS5
reported Zn concentrations higher than the guideline for the protection of ecosystem health.
SASS 5, PES and EIS assessments indicated moderate to severe modifications of the river.
Thus, mining, industrial activities, surface runoff from densely populated informal settlements and wastewater treatment plants have negatively impacted upon the river. Decades of
environmental neglect and effluent discharge have degraded the ecosystem, thus necessitating
rehabilitation. However, as the study was limited in both time and scope, so additional research
should be undertaken. / Environmental Sciences / M. Sc. (Environmental Management)
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