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Vegetation succession and soil properties following the removal of pine plantations on the eastern shores of Lake St Lucia, South Africa.James, Barry Mark. January 1998 (has links)
Pine plantations have been established on secondary grassland on the dune systems of the
Eastern Shores of Lake St Lucia, KwaZulu-Natal, South Africa for the past 40 years. These
plantations have been progressively felled for the past six years, and will continue to be felled
until the year 2011, by which time they will be eliminated.
Space-for-time substitution was used to determine the direction of both woody and herbaceous
vegetation succession and to predict possible future management implications for the Eastern
Shores. Soil samples were taken from undisturbed grassland, grassland with trees, dune forest,
pine plantations, and clearfelled areas at various successional stages. To determine the effects
of the pine plantations on the soils of the area, soils were subjected to particle size analysis,
and determination of pH, organic carbon, phosphorus, exchangeable bases, iron and
aluminium.
Minimal modification of the sandy soils by the pine plantations was found to have occurred.
That which did occur was shown to be short-term, and to be ameliorated by the establishment
of an indigenous woody understorey, resembling pioneer dune forest. Soil under plantations
was shown to have a lower pH and cation exchange capacity than under opposite indigenous
vegetation but no other direct effects were observed. The direction of succession was
determined by the nature of the indigenous vegetation adjacent to the plantation. Pine
plantations were shown to facilitate succession towards dune forest by the exclusion of fire,
provision of perches and refugia for forest-dwelling animals, and creation of a forest
environment for the establishment of trees. However, the extent of re-establishment of
indigenous dune forest under pine plantations was shown to be directly related to the nature
of the adjacent indigenous vegetation, be it grassland, grassland with trees or dune forest. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 1998.
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Towards the feasibility of a landowner enterprise in the western Baviaanskloof : an external stakeholder analysisWiles, Kira Leigh Deborah January 2014 (has links)
In May 2012, a meeting was held between various stakeholder representatives of the Western Baviaanskloof to discuss the concept of a proposed landowner-enterprise. This concept was put forward in response to a need for collaboration in the midst of economic, environmental and social issues at play in the Baviaanskloof. Owing to the conservation value and rapidly decreasing economic output of the land, a radical shift to sustainable land-use practices was called for by various stakeholders. Suggested as a vehicle to generate income for the local landowners through alternative sustainable land-uses, the proposed enterprise may aid in addressing this shift by use of a bottom-up approach. During the stakeholder meeting, it was requested by the representative landowners that a feasibility assessment be conducted on the concept of the proposed enterprise prior to establishment. As an integral part of this assessment, the researcher took on the task of investigating stakeholder reception to the enterprise by means of a stakeholder analysis. It was decided to limit this to three markets: water, carbon and tourism. The purpose of this research study is twofold, namely to: investigate stakeholder influence and their reception of the proposed enterprise using a stakeholder analysis; and also to identify and advise on the opportunities and constraints relating to stakeholders, thus contributing to determining the feasibility of the proposed enterprise. In achieving the purpose of this study, a systematic stakeholder analysis framework was constructed, based on existing theory. This was necessary because, although stakeholder analysis is commonly practiced, no study was found to provide a theoretically based framework for the purpose of feasibility in the initial stages of enterprise establishment. Thus the contribution of the study is also twofold, namely the practical outcome of determining stakeholder reception for feasibility, and a secondary outcome of constructing a stakeholder analysis framework. The stakeholder analysis framework is based on an interpretation of existing stakeholder theory, with the addition of four "relational indicators" – goals, intentions, relationships, and resources. These four indicators provide a link between theory and practice in gauging the two attributes of stakeholder influence – power and interest. Dealing with a number of stakeholder interests in a unique context, the study takes on a single network case study approach in the paradigm of phenomenology. To suit the complex nature of the study, semi-structured interviews with various stakeholder representatives were conducted, using groups or organisations as units of analysis. Drawing from the stakeholder analysis framework and overall purpose of the study, four research objectives were set. The first was to identify the proposed enterprise's legitimate key external stakeholders, based on the three markets: water, carbon and tourism; the second to describe, categorise and assess relative dyadic influence of the above stakeholders by gauging their power and interest; the third, to determine the stakeholder network influence and probable reception of the proposed enterprise; and the last to advise the landowners on any identified opportunities or constraints stakeholders might pose, and thus to contribute to determining feasibility. In addressing the first objective, 21 stakeholders were identified, 12 of whom were found to be key to the current investigation. These key stakeholders were: Gamtoos Irrigation Board (GIB), LivingLands, R3G, Rhodes Restoration Group, Eastern Cape Parks and Tourism Agency (ECPTA), Department of Water Affairs (DWA), Nelson Mandela Bay Metropolitan (NMBM), Saaimanshoek, South African National Biodiversity Institute (SANBI), Department of Economic Development, Environmental Affairs and Tourism (DEDEAT), Baviaans Tourism, and Baviaans Municipality. In applying the stakeholder analysis framework, ECPTA was categorised as the definitive (most influential) stakeholder to the enterprise, and DEDEAT, SANBI (through Working for Wetlands), Baviaans Tourism, GIB, and NMBM were categorised as pivotal (influential and active). In discerning stakeholder interest in the proposed enterprise, a number of emerging themes were found to affect the projected interest and behaviour of stakeholders, apart from their specified goals. Emerging themes included: tunnel visioning, internal disparity, individual/personality clashes, and misaligned interests. In addition to this, in interpreting stakeholder interest, specific intentions or agendas that might affect the interest shown towards the proposed enterprise were also taken into account. Five predominant intentions of stakeholders were identified as: implementing a stewardship programme, establishing a tourism association, establishing a water users' association, social development, and "the big vision". Findings on the final objective revealed a number of perceived opportunities and constraints relative to the feasibility of the enterprise. Three prime opportunities were identified as: partnerships with definitive and pivotal stakeholders, the possibility of tendering for implementer of the "Working for" programmes, and taking on the role of Tourism Association. The following potential constraints were also emphasised by participants: social aspects such as individuals and personalities, the incompatibility or non-existence of local market structures, and the need for external funding. With regard to stakeholder reception, most of the stakeholders, with the exception of NMBM and Saaimanshoek, responded positively to the idea of the enterprise. Overall, based on participant perceptions, the tourism market was found to be the most feasible the carbon market uncertain and a long-term possibility, and the water market the least feasible.
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The Influence of Urban Green Spaces on Declining Bumble Bees (Hymenoptera: Apidae)Beckham, Jessica L. 05 1900 (has links)
Bumble bees (Bombus spp.) are adept pollinators of countless cultivated and wild flowering plants, but many species have experienced declines in recent decades. Though urban sprawl has been implicated as a driving force of such losses, urban green spaces hold the potential to serve as habitat islands for bumble bees. As human populations continue to grow and metropolitan areas become larger, the survival of many bumble bee species will hinge on the identification and implementation of appropriate conservation measures at regional and finer scales. North Texas is home to some the fastest-growing urban areas in the country, including Denton County, as well as at least two declining bumble bee species (B. pensylvanicus and B. fraternus). Using a combination of field , molevular DNA and GIS methods I evaluated the persistence of historic bumble bee species in Denton County, and investigated the genetic structure and connectivity of the populations in these spaces. Field sampling resulted in the discovery of both B. pensylvanicus and B. fraternus in Denton County's urban green spaces. While the relative abundance of B. fraternus in these spaces was significantly lower than historic levels gleaned from museum recors, that of B. pensylvanicus was significantly higher. Statistical analyses found that both bare ground and tree cover surrounding sample sites were negatively associated with numbers of bumble bee individuals and hives detected in these green spaces. Additionally, limited genetic structuring of bumble bee populations was detected, leading to the conclusion that extensive gene flow is occurring across populations in Denton County.
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An investigation into the contribution of housing developments to wetland degradation within the city of Harare, ZimbabweMutisi, Luke 03 July 2015 (has links)
Wetlands are fragile ecosystems that deliver a wide range of environmental and ecosystem services that contribute to human well-being. This fragility has seen a number of wetlands succumb to degradations and loss arising from different causes. The positive contribution of wetlands to various ecosystems and the increasing rate of their degradation and loss has been a cause for concern to different stakeholders for a long time. One of the landmark indications of this concern is the constitution of the Ramsar Convention that was held in Iran in 1971 with the objective of addressing concerns regarding to wetland degradation and loss. Among the competing land uses resulting in wetlands loss and degradation could be listed urban agriculture, industrial development and housing.
The research sought to assess the extent of wetland degradation with respect to housing
developments in Harare, Zimbabwe. The dilemma as to why and how wetlands were being degraded was an issue of concern. The research sought to determine whether abatement or mitigation measures were in place to address the challenges Associated with wetlands loss and degradation. The subsequent growth of developments, their associated activities and possible intervention measures had to be thoroughly assessed.
The administration of questionnaires and conducting of interviews was done to solicit data from the respondents. Collected data was analyzed through the Statistical Package for Social Scientists. Further to this, Google satellite imagery was used in the mapping of the Belvedere North and Epworth suburbs. Disturbed and undisturbed portions of the wetlands were analyzed by Geographical Information System software. Direct observation of the wetland area was used to examine existing natural features. To determine extent of pollution, water samples were collected in the wetlands and submitted to the laboratory for analysis. Analysis of selected chemical and physical parameters was carried out in the laboratory using selected methods.
The research made two important and broad findings. First, both the Belvedere North and Epworth wetlands have been severely degraded by anthropogenic activities with housing developments and urban agriculture as the major contributors of this degradation. The development of residential properties in the wetlands is a result of a high demand for residential space in Harare. Whereas housing developments in Belvedere are formal and planned, developments in Epworth were informal and haphazard. With no formal planning, the Epworth wetlands have been severely impacted by water and sand extraction as well as contamination of underground water by pit-latrines that are common in these informal settlements. Second, the research also found that wetland degradation was closely associated with the lack of clear
wetland policies both at national and local levels. The laboratory results showed that the water in Epworth was more polluted than the water in Belvedere. The measure of pollutants in Epworth was higher due to the activities being carried out as compared to Belvedere. Measures of Dissolved Oxygen, Total Dissolved Substances and conductivity increased from October to March in Epworth. Of note is the measure of Dissolved Oxygen that increased between October and March with a mean of 7.9 and 2.5 respectively. Total nitrogen and total phosphate also increased significantly in midstream and downstream sections. In essence, averages of 0.01 in October and 0.04 in March were recorded respectively for total nitrogen. The study concludes that an integrated land use approach has the potential of minimizing wetland loss and
degradation. This is possible through the formulation and implementation of a comprehensive policy involving all relevant stakeholders. This will ensure a coherent decision making process. In as much as integrated land use planning and policy formulation are potential approaches to wetland sustainability, the drive to implement policy by policy makers concerning wetlands has to be explored. As ignorance concerning the ecological importance of wetlands exists in some cases, it is critical to consider wetland benefits above other competing developments such as housing and urban agriculture. This can be achieved through merging interrelated disciplines with the idea of integrating wetland information. For instance, deriving engineering solutions
could promote development yet preserving wetlands. It is also suggested that environmental impact assessments, as planning tools should be carried out simultaneously with the town planning aspect. If given to proper planning, wetlands have a huge chance of survival. / Environmental Sciences / M.Sc. (Environmental Management)
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A river health assessment of selected South-Western Cape Rivers : index of habitat integrity, water quality and the influence of surrounding land useDawson, Emily Kathleen 12 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2003. / ENGLISH ABSTRACT: The River Health Programme (RHP) is an assessment tool for monitoring the ecological state of
rivers to ensure that they remain fit for use by present and future generations. This study, forming
part of a RHP assessment conducted on the south-western Cape Hout Bay, Lourens and Palmiet
Rivers, has the aim to (1) zone the rivers for representative site selection, (2) assess their habitat
integrity (HI), (3) determine the influence of land use on riverine HI and (4) assess the river water
quality at the time of the RHP assessments.
(1) The desktop geomorphological zonation method used in RHP assessments has not been
sufficiently previously tested on short rivers draining the Western Cape Mountains. The
Lowland River Zone of the rivers studied, as well as the Hout Bay River’s Upper Foothill Zone,
were found to have steeper gradients than expected, probably due to these rivers being shorter
and consequently steeper than any on which the method was previously tested. The notion of
one gradient river classification system being applicable throughout South Africa, with its
diverse geology and climate, is unlikely. Rather a classification system modified for various
physiographic features regions or by a factor based on river length is more realistic.
(2) Although there is a general longitudinal decrease in HI downstream along the Hout Bay and
Lourens Rivers, coinciding with increased anthropogenic activities, HI improves in the Palmiet
River’s lower reaches through the Kogelberg Nature Reserve. Surrounding land use thus seems
to be a major determinant of HI. Although the Index of Habitat Integrity (IHI) used appears to
achieve its aim, it was found to be subjective. Categorisation of the IHI scoring is suggested.
(3) The amount of natural versus disturbed land use occurring upstream of a site at a regional and
local scale, is a good predictor of riverine HI. Regional alien forestry and local urbanisation
have significantly strong negative effects on instream (r2 = -0.80, r2 = 0.80, p<0.05) and riparian
(r2 = -0.81, r2 = -0.83, p<0.05) HI. Different land use types therefore appear to affect riverine HI
at differing scales and thus managers must not only think on a local but also a catchment scale.
(4) In the Hout Bay River, a filtering system (e.g. wetland) appears to improve the water quality
between the middle and lower reaches. Along the Lourens River, high total dissolved salts,
conductivity and inorganic nitrogen concentrations in the middle reaches are cause for concern.
Along the Palmiet River there appeared to be insufficient oxygen to support most aquatic life
forms at Grabouw. Impoundments in the middle reaches act as sinks for nutrients and salts, but
the Huis and Krom tributaries downstream then appear to degrade the water quality of the
Palmiet River’s lower reaches within the Kogelberg Nature Reserve.
Together with the results of simultaneous biotic assessments, these results should be used to
develop management actions to improve the ecological health of these rivers. The results have been
used in a State-of-Rivers Report for the south-western Cape. / AFRIKAANSE OPSOMMING: Die Riviergesondheidsprogram (RGP) is 'n asseseringsinstrument wat die ekologiese stand van
riviere monitor om te verseker dat hulle steeds bruikbaar bly vir huidige en toekomstige geslagte.
Hierdie studie maak deel uit van 'n RGP-assessering van die Lourens-, Houtbaai- en Palmietrivier in
die Suidwes-Kaap en het ten doel om (1) die riviere te soneer vir verteenwoordigende
terreinseleksie, (2) die habitat-integriteit (HI) te assesseer, (3) die invloed van grondgebruik op
rivier-HI te bepaal en (4) die kwaliteit van rivierwater tydens die RGP-assesserings te bepaal.
(1) Die geomorfologiese-soneringsmetode wat in RGP-assesserings gebruik word, is nog nie
voorheen genoegsaam vir die kort riviere wat die Wes-Kaapse berge dreineer, getoets nie. Daar is
bevind dat die studiegebied riviere in die laagland-sones skerper gradiënte het as verwag, gehad het.
Dit kan moontlik toegeskryf word aan die riviere wat korter en dus steiler is as enige van dié wat
voorheen met die metode getoets is. Die moontlikheid dat een gradiëntklassifikasiestelsel vir riviere
regdeur Suid-Afrika met sy diverse geologie en klimaat toegepas kan word, is onwaarskynlik. 'n
Klassifikasiestelsel aangepas vir verskillende fisiografiese streke of met 'n faktor gebaseer op
rivierlengte, is meer realisties.
(2) Alhoewel HI stroomaf langs die Lourens- en Houtbaairivier in die algemeen longitudinaal saam
met die toename in antropogeniese aktiwiteite afneem, verbeter die Palmietrivier se HI waar dit laer
af deur die Kogelbergnatuurreservaat vloei. Die gebruike van aanliggende grond blyk dus 'n
belangrike bepaler van HI te wees. Die Indeks van Habitatintegriteit (IHI) bereik klaarblyklik die
vereiste doel, maar is te subjektief. Kategorisering van die IHI-waardes word voorgestel.
(3) 'n Goeie voorspeller van rivier-HI is die hoeveelheid natuurlike teenoor versteurde grondgebruik
stroomop van 'n terrein op 'n streeks- en lokale skaal. Die sterk negatiewe effek van uitheemse
plantegroei in die omgewing en lokale verstedeliking op stroom- (r² = -0.80, r² = 0.80, p<0.05 ) en
oewer-HI (r² = -0.81, r² = -0.83, p<0.05) is beduidend. Verskille in tipe grondgebruik beïnvloed
rivier-HI op verskillende vlakke; bestuurders moet dus plaaslik en aan die opvanggebied dink.
(4) In die Houtbaairivier lyk dit asof 'n filtreringstelsel (bv. vleigrond) die waterkwaliteit tussen die
middel- en lae gedeeltes verbeter. In die loop van die Lourensrivier is hoë totale opgeloste soute,
geleidingsvermoë en anorganiese stikstofkonsentrasies in die middelgedeelte 'n rede tot kommer. In
die Palmietrivier by Grabouw was die suurstof te min om die meeste akwatiese lewensvorme te
onderhou. Opgedamde water in die middel gedeeltes dien as 'n sink vir voedingstowwe en soute,
maar dit lyk asof die Huis- en Kromrivier die waterkwaliteit van die Palmietrivier stroomaf in die
Kogelbergnatuurreservaat degradeer.
Saam met die resultate van gelyktydige biotiese assesserings, kan hierdie resultate gebruik word vir
die ontwikkeling van bestuursaksies om die ekologiese toestand van hierdie riviere te verbeter. Die
resultate is gebruik in 'n toestand-van-riviere-verslag vir die Suidwes-Kaap.
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An investigation into the contribution of housing developments to wetland degradation within the city of Harare, ZimbabweMutisi, Luke 03 July 2015 (has links)
Wetlands are fragile ecosystems that deliver a wide range of environmental and ecosystem services that contribute to human well-being. This fragility has seen a number of wetlands succumb to degradations and loss arising from different causes. The positive contribution of wetlands to various ecosystems and the increasing rate of their degradation and loss has been a cause for concern to different stakeholders for a long time. One of the landmark indications of this concern is the constitution of the Ramsar Convention that was held in Iran in 1971 with the objective of addressing concerns regarding to wetland degradation and loss. Among the competing land uses resulting in wetlands loss and degradation could be listed urban agriculture, industrial development and housing.
The research sought to assess the extent of wetland degradation with respect to housing
developments in Harare, Zimbabwe. The dilemma as to why and how wetlands were being degraded was an issue of concern. The research sought to determine whether abatement or mitigation measures were in place to address the challenges Associated with wetlands loss and degradation. The subsequent growth of developments, their associated activities and possible intervention measures had to be thoroughly assessed.
The administration of questionnaires and conducting of interviews was done to solicit data from the respondents. Collected data was analyzed through the Statistical Package for Social Scientists. Further to this, Google satellite imagery was used in the mapping of the Belvedere North and Epworth suburbs. Disturbed and undisturbed portions of the wetlands were analyzed by Geographical Information System software. Direct observation of the wetland area was used to examine existing natural features. To determine extent of pollution, water samples were collected in the wetlands and submitted to the laboratory for analysis. Analysis of selected chemical and physical parameters was carried out in the laboratory using selected methods.
The research made two important and broad findings. First, both the Belvedere North and Epworth wetlands have been severely degraded by anthropogenic activities with housing developments and urban agriculture as the major contributors of this degradation. The development of residential properties in the wetlands is a result of a high demand for residential space in Harare. Whereas housing developments in Belvedere are formal and planned, developments in Epworth were informal and haphazard. With no formal planning, the Epworth wetlands have been severely impacted by water and sand extraction as well as contamination of underground water by pit-latrines that are common in these informal settlements. Second, the research also found that wetland degradation was closely associated with the lack of clear
wetland policies both at national and local levels. The laboratory results showed that the water in Epworth was more polluted than the water in Belvedere. The measure of pollutants in Epworth was higher due to the activities being carried out as compared to Belvedere. Measures of Dissolved Oxygen, Total Dissolved Substances and conductivity increased from October to March in Epworth. Of note is the measure of Dissolved Oxygen that increased between October and March with a mean of 7.9 and 2.5 respectively. Total nitrogen and total phosphate also increased significantly in midstream and downstream sections. In essence, averages of 0.01 in October and 0.04 in March were recorded respectively for total nitrogen. The study concludes that an integrated land use approach has the potential of minimizing wetland loss and
degradation. This is possible through the formulation and implementation of a comprehensive policy involving all relevant stakeholders. This will ensure a coherent decision making process. In as much as integrated land use planning and policy formulation are potential approaches to wetland sustainability, the drive to implement policy by policy makers concerning wetlands has to be explored. As ignorance concerning the ecological importance of wetlands exists in some cases, it is critical to consider wetland benefits above other competing developments such as housing and urban agriculture. This can be achieved through merging interrelated disciplines with the idea of integrating wetland information. For instance, deriving engineering solutions
could promote development yet preserving wetlands. It is also suggested that environmental impact assessments, as planning tools should be carried out simultaneously with the town planning aspect. If given to proper planning, wetlands have a huge chance of survival. / Environmental Sciences / M. Sc. (Environmental Management)
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Impact of land use on water quality and aquatic ecosystem health of stream networks in the upper uMngeni catchment feeding Midmar Dam, KwaZulu-Natal, South Africa.Van Deventer, Ross. January 2012 (has links)
Freshwater in adequate supply and quality is vital to life on Earth; however, land-based activities such as development, agriculture, mining and industry, and their associated contaminants, pose a major threat to the quality of freshwater water resources and health of aquatic ecosystems. The upper uMngeni catchment draining into Midmar Dam is a strategically significant water resource, supplying clean drinking water to the eThekwini, uMgungundlovu and Msunduzi municipalities. The quality of
this resource is under threat from current land-based activities such as Mpophomeni settlement and
agriculture and emerging threats in the form of the Khayalisha social housing project. Monitoring sites were established in varying land use types in three sub-catchments of the upper uMngeni, to assess water quality and ecosystem health impacts of current land uses on Midmar Dam. A suite of physical, chemical and biological water parameters were sampled in conjunction with SASS5 bio-monitoring to assess the associated impacts. Water quality and ecological condition were highest in forested land use and upstream of Mpophomeni where natural land cover and sparse settlement occurred. Marked declines in water quality and ecological condition were observed at areas under commercial agriculture, indicated predominantly by rises in nutrient concentrations and declines in the SASS5 indices. The most notable declines in water quality and ecological condition were observed at sites downstream of Mpophomeni settlement as a result of severe sewage contamination, indicated by high E. coli counts. Nutrient concentrations downstream of Mpophomeni settlement ranged from mesotrophic to hypertrophic, with nitrogen to phosphorus ratios indicative of nitrogen limitation. Ecological condition remained in the ‘seriously/critically modified’ category over the study period.
Nutrient loads produced by Mpophomeni are the highest of all the land uses, followed by that of commercial agriculture; both should be viewed as a concern, more so when viewed in terms of their compound effect on Midmar Dam water quality. Current water quality draining the commissioned Khayalisha social housing development area is good and although not natural, is of no contamination
concern to Midmar Dam. Results indicate that with current land use activities, urban development and agriculture pose a potential threat to the quality of Midmar Dam resource and that further development in the form of the Khayalisha social housing project may replicate impacts already prevailing in Mpophomeni, whereby a principle water resource may be threatened by eutrophication. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.
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Change in land cover and water abstraction : modelling runoff effects in the Bot River CatchmentStipinovich, Amalia 12 1900 (has links)
Thesis (MA (Geography and Environmental Studies))--University of Stellenbosch, 2005. / River basins have long been attracting human settlement and development, promising water and
fertile lands (Newson 1992). The Bot River Catchment on the southern coast of South Africa is
no exception. However, much of the development in this catchment has not been controlled and
its land and water resources are being abused. This is affecting the water quality and quantity of
the river system and estuary at an alarming rate.
In this thesis, the ‘reference’ land cover in the Bot River Catchment is recreated. This term is
used to describe “the hydrological state of the catchment as it was when completely covered in
natural vegetation, thus before it was impacted by humans” (Jacobs & Bruwer 2002:12). A
rainfall-runoff model is employed to investigate the effects of various land covers on the
catchment’s runoff quantity, by comparing the simulation results of the catchment’s reference
and current state.
The results of the model point to a large reduction in runoff since the reference state of the
catchment. As the rainfall-runoff model applied did not allow for modelling of the annual
agriculture that dominates the catchment, the runoff reduction was attributed to the smaller areas
of perennial agriculture, forestry and alien vegetation infestation. The simulation results
confirmed the threat of current land use practices on the environmental integrity of the Bot River
Catchment. A transition to agricultural practices that are more suited to the climate is suggested
and the eradication of alien vegetation should be seen as a priority. Most importantly, a holistic
approach should be taken towards the management of the Bot River Catchment.
The altered hydrodynamic regime of the Bot River Estuary is symptomatic of misuse of the
entire catchment. As ongoing demographic and land use pressures create a new generation of
water management problems (Department of Water Affairs & Forestry 1993), a deeper
understanding of the relationships between the different components in the Bot River Catchment
becomes increasingly urgent.
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The role of anthropogenic disturbance in the creation of a socio-ecological landscapeFox, Helen Elizabeth January 2005 (has links)
The aim of this thesis is to examine the role of anthropogenic disturbance in the creation of a socio-ecological landscape. Three key questions were answered: what impact has past anthropogenic disturbance had on present vegetative characteristics; what value did this disturbed landscape have to local people; how did the local peoples' worldviews and eco-cosmologies influence how they perceived, valued and managed their landscape? Research was based in a rural, predominantly amaXhosa village in the Kat River valley, Eastern Cape, South Africa. Four major landscape components characterised the environment, namely dense forests, former grazing lands, abandoned fields and old settlements. A combination of qualitative and quantitative methods were adopted, consisting of a vegetation and soil survey and social science methods including semistructured interviews, focus groups, transect walks and participant observation. The key finding was that anthropogenic disturbance is necessary to enhance the potential of the area to support human habitation. However, anthropogenic disturbance can have positive or negative effects for both local people and the environment. An intermediate level of disturbance is a key factor leading to a resilient socio-ecological system. Various anthropogenic disturbances have had significant affects on vegetation characteristics in terms of species richness, and a change in vegetation composition and species heights. Of the three anthropogenic landscapes examined, former grazing lands were the least intensively disturbed. They were also more species rich and structurally diverse than areas that were under agricultural production or used as a settlement. Dense forests, although the least desirable landscape to local people were, together with sacred pools, sources of ecosystem renewal and played a critical role during times of disturbance. Anthropogenic disturbance has added value to local people's livelihoods; this disturbance has resulted in a patchy landscape that supplies a wide variety of resources to local people. Local people are dependent on their environment for their basic needs; this has encouraged sustainable management practices. The local AmaXhosa still retain many elements of their traditional worldview, which has many characteristics of Animism. The environment is an integral component of their belief system and certain sites and species have significant cultural value and are protected.
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The mutual embodiment of landscape and livelihoods: an environmental history of NqabaraDe Klerk, Henning January 2007 (has links)
This thesis presents a history of the landscape of Nqabara, an administrative area in a rural and coastal area of the Eastern Cape Province, South Africa. In the process of investigating landscape history, the inquiry engages with a range of data sources from diverging discursive contexts, including data from ethnographic fieldwork, from the consultation of archival documents and historical reports as well as from comparative historic and ethnographic research, necessitating a critical consideration of the epistemological contexts of data production and the dialogue between researcher and data. Furthermore, in its aim to move beyond historical description towards explanation, the study interrogates the dualist ontological conceptualisations of nature and culture, society and ecology, object and meaning upon which are built three dominant conceptual frameworks concerned with human-environment relationships: social-ecological systems theory, transdisciplinary landscape studies and political ecology. Drawing primarily upon the works of James Gibson, Anthony Giddens and Tim Ingold, an ontological foundation is developed to guide the enquiry and move towards an alternative understanding of the relationship of people’s livelihoods with respect to the landscape in which it is lived, which I call here the praxisembodiment perspective. This ontology takes the situated patterns of action of a situated agent-in-its-environment as its point of departure and proceeds to develop a framework explaining how relations among the patterns of action of different agents-in-their-environment, emerge in structures that simultaneously enable and constrain future action. The foundation is thereby provided for a monist understanding of how landscape and social structure emerge simultaneously from the complex intersection of patterns of actions and interactions of agents in their environment. This framework calls for an understanding of time, space and scale, not as independent variables influencing process and action, but as emergent properties arising from the patterns of actions of situated agents. Finally the alternative ontology is applied to the history of landscape and livelihoods of people of Nqabara. It is concluded that an appropriate understanding and explanation of the critical transformations in the landscape as well as in social institutions, should be sought through analysis of the complex ways in which patterns of action of multiple spatial and temporal rhythms and between multiple agents in an environment, intersect and resonate.
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