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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Tourism policy, biodiversity conservation and management: a case study of the Kruger National Park, South Africa

Zhou, Leocadia January 2009 (has links)
The Kruger National Park (KNP) management has recently made considerable progress in enacting new policies to address biodiversity conservation and management challenges. However, the interlinkages among the new policies to support biodiversity conservation and management have not been evaluated, particularly the principles and approaches, and how these interact in terms of policy decision-making at the economic and political levels. This study seeks to evaluate the interlinkages among the new policies and how they affect one another, as an avenue to promote a more integrated and comprehensive policy implementation. These policies include the tourism policy, the elephant management policy, and the water provision policy. At policy-making level, the integration of these three policies enhances the possibilities for balancing and controlling the pressures exerted on environmental resources. At the implementation level, it offers a framework for the coordination of the interventions of the policies in space so as to recognise and capitalize on their synergies. Given the inevitably multifarious and departmentalized nature of policy formulation in the KNP, there is a need for the analysis of interlinkages amongst policies. The conceptual framework underpinning this study derives much from Briassoulis’ (2004) policy integration. The research utilizes both qualitative and quantitative research methods, and focuses on selected camp sites within the Park. The findings indicate that current procedures for tourism policy-making and implementation are weak, and little is done by way of impact assessment. This has been attributed to the lack of capacity at the KNP. The findings also reconfirm that policy-making is too fragmented. As a result, policy coordination and cooperation among park managers is weak. This study suggests that an environmental policy integration approach can lead to improved policy-making and implementation. Informed by the data collected from interviews, questionnaires and document analyses, a management framework has been developed to demonstrate how an integrated approach to Environmental Policy Integration (EPI) or management can help sustain the practice of wildlife tourism and support biodiversity conservation. It is concluded that greater realisation of integrated policy-making and implementation in the KNP can be achieved by establishing a formal coordinating office. However, a special feature of KNP policy-making is its widespread consultation system that can provide a fertile ground for enhancing EPI.
42

Body composition estimation and nutritional status of African buffalo (Syncerus caffer) in the Kruger National park

Erasmus, Marius Eugene Anton 13 December 2006 (has links)
Please read the abstract in the 00front part of this document / Dissertation (MSc Agric (Production Physiology))--University of Pretoria, 2006. / Animal and Wildlife Sciences / unrestricted
43

Die ultrastruktuur van sperme van die rooibok Aepyceros melampus (Lichtenstein, 1812) in die Nasionale Krugerwildtuin met spesiale verwysing na die invloed van koperbesoedeling

Ackerman, Dirk J. (Dirk Jacobus) 08 1900 (has links)
Thesis (PhD) -- Stellenbosch University, 1995. / ENGLISH ABSTRACT: Graling in the Kruger National Park. south of Phalaborwa Gate, is contaminated with copper, probably from a nearby copper refinery. Cattle in the neighbourhood have died from copper poisoning while the average copper concentration in the livers of impala in the Krgler National Park, was found to be abnormally high. The possibility exists that the ultrastructure of spermatozoa may serve as an indicator of environmental conditions. To examine this statement further, the purpose of this study includes the following: - To describe the ultrastructure of normal impala sperm as well as their abnormalities. - To quantify the sperm abnormalities of each experimental animal and to relate the abnormalities with the copper concentration in the impala liver, in order to determine whether any correlation exists between these two variables. Impala have been terminated monthly, from 1992.06.09 to 1993.05.15. in the vicinity of Phalaborwa Gate and in the Skukuza area for other research projects. Their sperm were made available for this study. The control group consisted of 20 animals which comprised 14 animals from an area, not contaminated with copper, along the Nwaswitshaka spruit near Skukula and 6 animals originally from the same area but which had been kept in captivity at Skukuza on a diet, not contaminated with copper. The experimental group consisted of 44 animals which comprised 32 animals from copper contaminated grazing along the Tshutshi spruit south of Phalaborwa Gate and 12 animals captured along the Nwaswitshaka spruit which were kept on a copper contaminated diet in captivity at Skukuza. Sperm from the epididymis of each animal were collected and fixed in a temporary laboratory. The sperm were processed at the Electron Microscopy Unit of the Faculty of Veterinary Science of the University of Pretoria and studied by means of scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The copper concentration in the liver was analyzed and bone marrow collected of each animal in order to determine the condition of the animal. The external morphology of a normal impala sperm was documented by means of SEM and the dimensions of the sperm determined. SEM micrographs of observed sperm abnormalities were taken. Percentages for normal sperm and the percentages of some abnormalities of a control group (Average liver copper concentration - ALCC = 37.9 ppm WB) were calculated. The same percentages were also calculated for an experimental group (ALCC = 104 ppm WB). The control group and the experimental group exhibited 91.6% and 93.6% normal sperm respectively. The difference in percentage sperm abnormalities of the two groups was of the same order. The increased copper in the livers of the experimental group has thus not lead to an increase of the percentage macro-abnormalities observed with SEM. The ultrastructure of normal impala sperm were described and documented with micrographs by means of TEM. The deviations of the normal sperm ultrastructure were also recorded on micrographs. Percentages were calculated for the normal sperm sections, as well as the abnormalities of some sperm sections of a contrl group (ALCC = 33.86 ppm WB). The same percentages were also calculated for an experimental group (ALCC = 122.5 ppm WB). For the control group the average percentage sperm neck sections with vacuoles was : 31.5% and for the experimental group this percentage was : 57.9%. The increased copper concentrations in the livers of the experimental group thus led to an increase of the percentage of sperm necks with vacuoles. There is also reason to believe that the difference of the percentages of sections of the sperm head, in the control and experimental group, should be remarkably greater. A graphic analysis of the TEM-data has also shown that a statistically significant correlation exists between the percentage of sperm with vacuoles in the neck and the copper concentrations in the livers of impalas. The conclusion is that high level copper concentrations exert a detrimental effect on the ultrastructure of the sperm neck. The possibility also exists that copper concentrations in impala liver > 500 ppm WB. will show a correlation with the percentages of some of the other abnormalities observed. / AFRIKAANSE OPSOMMING: Die weiding suid van Phalaborwahek in die Krugerwildtuin word waarskynlik vanaf 'n nabygeleë kopersmeltery met koper besoedel. Van die plaasdiere in die omgewing het reeds van kopervergiftiging gevrek en die gemiddeIde koperkonsentrasie in die lewers van rooibokke is abnormaal hoog. Die moontlikheid bestaan dat die ultrastruktuur van spermatozoa as 'n indikator van omgewingstoestande kan dien. Om bogenoemde moontlikheid verder te ondersoek was die doelwit van hierdie studie die volgende: Om die ultrastruktuur van normaIe rooiboksperme en hulle abnormaliteite te beskryf en die spermabnormaliteite van elke proefdier te kwantifiseer en met die koperkonsentrasie in die lewer in verband te bring om sodoende te bepaal of daar 'n korrelasie tussen die twee veranderlikes bestaan. Rooibokke wat maandeliks vanaf 1992.06.09 tot 1993.05.15 vir ander navorsingsprojekte in die omgewing van Phalaborwahek en Skukuza getermineer is, se sperme is vir die studie beskikbaar gestel. Die kontrolegroep het bestaan uit 20 diere wat saamgestel is uit 14 diere afkomstig van die Nwaswitshakaspruit naby Skukuza, uit 'n gebied wat nie met koper besoedel is nie en 6 diere uit 'n groep wat oorspronklik uit dieselfde gebied gekom het, maar wat te Skukuza in aanhouding geleef het op voedsel wat nie met koper besoedel was nie. Die eksperimentele groep het bestaan uit 44 diere waarvan 32 in die omgewing van die Tshutshispruit suid van Phalaborwahek versamel is en die ander 12 diere is langs die Nwaswitshakaspruit gevang en op 'n koperbesoedelde dieet te Skukuza aangehou. Sperme uit die epididymis van elke dier is in 'n tydelike laboratorium versamel en gefikseer. By die Elektronmikroskopie Eenheid van die Fakutreit van Veeartsenykunde van die Universiteit van Pretoria is die sperme voorberei en met behulp van skandeerelektronmikroskopie (SEM) en transmissie-elektronmikroskopie (TEM) bestudeer. Die koperkonsentrasie in die lewer is bepaal en murgvet is versamel om die kondisie van die diere te bepaaI. Met SEM is die uitwendige morfologie van 'n normale rooiboksperm met mikrograwe gedokumenteer en die mates van die sperm bepaal. Mikrograwe van waargeneemde spermabnormaliteite is met SEM geneem. Persentasies is vir normale sperme en die abnormaliteite van sommige sperme van 'n kontrolegroep (Gemiddelde lewerkoperkonsentrasie - GLKK =37.9 dpm NB) bereken. Dieselfde persentasies is ook vir 'n eksperimentele groep (GLKK = 104 dpm NB) bereken. Van die kontrolegroep het 91.6% en van die eksperimentele groep 93.6% sperme normaal vertoon. Die verskil in persentasies spermafwykings van die twee groepe was ook van dieselfde orde. Die verhoogde koperkonsentrasie in die lewers van die eksperimentele groep het dus nie gelei tot 'n verhoging van die persentasie makro-abnormaliteite wat met SEM waargeneem is nie. Die ultrastruktuur van 'n normale rooiboksperm is met behulp van TEM beskryf en met mikrograwe gedokumenteer. Die afwykings van die spermultrastruktuur is ook op mikrograwe vasgelê. Persentasies is vir die normale spermsneë en die abnormaliteite van sommige spermsneë van 'n kontrolegroep (GLKK = 33.86 dpm NB) bereken. Dieselfde persentasies is ook vir 'n eksperimentele groep (GLKK = 122.5 dpm NB) bereken. Vir die kontrolegroep was die persentasie neksneë met vakuoles = 31.5% en vir die eksperimentele groep was die persentasie = 57.9%. Die verhoogde koperkonsentrasie in die lewer van die eksperimentele groep het dus gelei tot 'n verhoging van die persentasie neksneë met vakuoles. Rede bestaan om te glo dat die verskil van die persentasies kopsneë van die kontrole- en eksperimentele groep ook aansienlik hoër behoort te wees. 'n Grafiese analise van die TEM-data het ook getoon dat daar 'n statisties betekenisvolle korrelasie tussen die persentasie spermnekke met vakuoles en die koperkonsentrasie in die lewer van rooibokke bestaan. Die bevinding is dat hoë lewerkoperkonsentrasies 'n nadelige invloed op die ultrastruktuur van die spermnek uitoefen. Die moontlikheid bestaan ook dat koperkonsentrasies in die lewer > 500 dpm NB ook 'n korrelasie met sommige van die ander abnormaliteite sal toon.
44

Molecular ecology and invasive species management: unravelling the dynamics of Lantana camara invasions in the Kruger National Park, South Africa using a molecular approach

Vardien, Waafeka 03 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Non-native species are recognized as a major component of global environmental change. Their ecological impacts are numerous and include the alteration of whole ecosystem processes as well as the loss of native biodiversity. As such, understanding the processes that drive the invasion of non-native species is essential for the control and management thereof. Numerous research approaches have been used to provide insight on the history and ecology of non-native species invasions. However, recent approaches employing molecular techniques have greatly helped in solving taxonomic issues associated with some of these species; identifying sources of invasions; and shedding light on colonization dynamics. Lantana camara, a globally invasive and highly variable species complex, is one of the most notorious plant invaders in South Africa. The species has been associated with negative impacts in agricultural areas, decreased invertebrate diversity, livestock mortality, and where it occurs along riparian areas- decreased water quality and obstruction to accessing water sources. This project aimed to review L. camara invasions in South Africa and to unravel patterns of spread in L. camara along the Sabie-Sand catchment in South Africa’s flagship protected area, the Kruger National Park, using a molecular approach. The findings of the first part of the study highlight that L. camara has successfully spread across South Africa with only four known introduction events, and this can be attributed to the species’ broad ecological tolerance, its use in the horticultural industry, and a variety of dispersal vectors (birds, humans and rivers). Furthermore, although sale of the species is prohibited in the country, it will continue to spread naturally and also has the potential to expand its distribution under changing climate scenarios. The second part of the study highlights that spread along the Sabie-Sand catchment is primarily river-driven and that the Sand tributary is the invasion source in the system. Because the Sand tributary originates outside the Kruger National Park, and only a small portion is under park management, the implications for spread are important. / AFRIKAANSE OPSOMMING: Nie-inheemse spesies word erken as 'n belangrike komponent van die globale omgewing verandering. Hulle ekologiese impak is talle en sluit in die verandering van ekosisteem prosesse asook die verlies van inheemse biodiversiteit. As sodanig, die begrip van die prosesse wat lei tot die inval van 'n nie-inheemse spesies is noodsaaklik vir die beheer en bestuur daarvan. Talle navorsingsbenaderings is gebruik om insig te gee oor die geskiedenis en ekologie van nie-inheemse spesies invalle. Onlangse benaderings soos die gebruik van molekulêre tegnieke, help in die oplossing van taksonomiese kwessies wat verband hou met 'n paar van hierdie spesies,in die identifisering van bronne van invalle, en om lig te werp op die kolonisasie dinamika. Lantana camara, 'n wêreldwye indringende en spesie kompleks, is een van die mees berugte plantindringer in Suid-Afrika. Die spesie is geassosieer met negatiewe gevolge in landbou gebiede, afgeneem ongewerwelde diversiteit, vee mortaliteit, en waar dit voorkom saam oewer gebiede - afgeneem kwaliteit van die water en obstruksie tot waterbronne. Hierdie projek is daarop gemik om om L. camara invalle in Suid-Afrika te hersien en patrone van verspreiding te ontrafel in L. camara langs die Sabie-Sand-opvanggebied in Suid-Afrika se vlagskip beskermde gebied, die Kruger Nasionale Park, met behulp van 'n molekulêre benadering. Die bevindinge van die eerste deel van die studie wys dat L. camara het suksesvol versprei oor die hele Suid-Afrika met slegs vier bekende inleiding gebeure, en dit kan toegeskryf word aan die spesie se breë ekologiese verdraagsaamheid, die gebruik daarvan in die hortologie bedryf, en 'n verskeidenheid van die verspreiding vektore (voëls, mens en riviere). Verder, hoewel die verkoop van die spesie in die land verbied word, sal dit natuurlik voortgaan om te versprei en het ook die potensiaal om uit te brui onder veranderende klimaat scenario's. Die tweede deel van die studie wys dat versprei langs die Sabie-Sandopvanggebied hoofsaaklik rivier-gedrewe is en dat die Sand sytak die inval bron is. Omdat die Sand sytak buite die Kruger Nasionale Park ontstaan, en slegs 'n klein gedeelte onder park bestuur is, is die implikasies vir verspreiding belangrik. / Financial support from the DST-NRF Centre of Excellence for Invasion Biology and the Working for Water (WfW) Programme through their collaborative project on “Research for Integrated Management of Invasive Alien Species” and Stellenbosch University’s Subcommittee B Young Researcher's Fund
45

The influence of pan characteristics on their seasonal usage by mammals within the Makuleke Ramsar Wetland System

Antrobus, Romy 30 January 2015 (has links)
A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of requirements for the degree of Master of Science. / Central to the study of animal ecology is the usage an animal makes of its environment. In arid and semi-arid environments worldwide, the availability of surface water largely determines the behaviour, distribution and abundance of animals. As a consequence, the distribution and quality of water are factors that influence carrying capacities of protected areas in environments such as the Kruger National Park, South Africa. Just as wildlife may select water sources according to water quality, they may also select drinking locations according to perceived predation risk. Predation risk can therefore strongly influence the patch use and resource selection of animals. Similarly, human traffic and activity in natural areas can also have an effect on the behaviour and resource use of resident wildlife. This research investigates mammal usage patterns at selected water sources within the Makuleke Wetland System in Kruger National Park to contribute towards management planning for this important Ramsar Wetland Site. The research examines daily and seasonal trends in usage as well as possible links to water quality, land cover and human disturbance. Camera traps were set up seasonally at perennial pans and rivers within the Makuleke Wetland system to determine mammal species’ usage patterns. Environmental characteristics associated with each water source, such as water quality, vegetation cover and extent of human activity were also determined. A cluster analysis and Canonical Correspondence Analysis (CCA) were run in order to determine how environmental variables may influence mammal species’ seasonal drinking site selection. Overall, mammals appear to be selecting for drinking sites with increased distances to ground cover where they are more likely to see predators in advance. Mammal species appear to be avoiding the Zimbabwean border as a result of human activity in the Zimbabwean side of the Great Limpopo Transfrontier Park. The perennial pans and rivers appear to be a significant water source during the dry months to large herbivore and large carnivore species, which display the greatest seasonal fluctuations. Elephants show the greatest demand for water during the dry season and access the perennial water sources throughout the day and night. The Makuleke wetland system, and in particular the perennial water sources, provide an important dry season refuge for the northern Kruger National Park’s and the Greater Limpopo Transfrontier Park’s elephant population. The Luvuvhu River and its associated pan (Nwambe), within its floodplain, are sources of water for the greatest diversity and richness of species when compared to the water sources associated with the Limpopo floodplain, within the Makuleke Wetland System. Information from this study may aid South African National Parks management with their “adaptive management” strategy for Kruger National Park, to manage the park in an ever changing environment. It is widely accepted that emphasis be placed on the major role river systems play in biodiversity, and hence their high priority in conservation.
46

The role of price sensitivity and pricing in the demand for accommodation of local visitors to the Kruger National Park

Schutte, Ignatius Christian 11 June 2013 (has links)
The need for the study was prompted by discussions with my fellow photographers and friends that fewer people visited the Kruger National Park the last few years. Various reasons were given for it. I discussed it with Professors G. Puth and A. N. Schreuder, and members of the National Parks Board. Initially it was decided that a study should be done of why there was a decrease in the demand for accommodation in the Park, and how it could possibly be improved. Mr. P. Fearnhead and Professor A. N. Schreuder suggested that it would be better if a price sensitivity study should be done with a new computer program, namely conjoint analysis. This type of study has not been done in South Africa before. One of the major purposes of a conjoint analysis is to measure consumer preferences among competitive products and services. Basically it measures preferences of tourists by making trade-offs between five attributes and seventeen levels, and that consumers make complex decisions not on one factor alone but on several factors "jointly". Thus it was named conjoint analysis. Ranking a number of different combinations of attribute levels on a nine-point rating scale indicated their preferences. The results were then processed by a computer program, Conjoint Value Analysis (CVA), Version 2.0 system. They indicated their preferences by ranking a number of different combinations of attribute levels to give utility values for the attributes. Six representative camps (three large and three small ones) were used for a stratified sample of 428 respondents. The findings will give recommendations that can be used. AFRIKAANS : Die behoefte vir die studie is aangespoor deur gesprekke met my medefotograwe en vriende dat minder mense die Nasionale Kruger Wildtuin die laaste aantal jare besoek het. Veskeie redes is daarvoor gegee. Ek het dit met Professore G. Puth en A. N. Schreuder, en lede van die Nasionale Parkeraad bespreek. Oorspronklik is besluit dat 'n studie gedoen behoort te word oar hoekom daar 'n afname in die vraag vir akkommodasie in die Wildtuin was, en hoe dit moontlik verbeter kon word. Mnr. P. Fearnhead en Professor A. N. Schreuder het voorgestel dat dit beter sou wees indien 'n prysssensitiwiteit-studie met 'n nuwe rekenaarprogram, nl. gesamentlike analise ("conjoint analysis"), gedoen sou word. Hierdie tipe studie was nag nie voorheen in Suid-Afrika gedoen nie. Een van die hoof oogmerke van 'n gesamentlike analise is om verbruiksvoorkeure tussen mededingende produkte en dienste te meet. Basies meet dit voorkeure van toeriste deur kompromiee ("trade-offs") tussen vyf eienskappe en sewentien vlakke te maak, en dat verbruikers komplekse besluite maak nie oar een eienskap aileen nie, maar verskeie eienskappe gesamentlik ("jointly"). Daarom is dit gesamentlike analise ("conjoint analysis") genoem. Hulle voorkeure word gewys deur die toekenning van 'n rangorde aan 'n aantal veskillende kombinasies van eienskap-vlakke op 'n nege-punt skattingskaal. Die resultate is daarna deur 'n rekenaarprogram, Conjoint Value Analysis (CVA), Version 2.0 sisteem, verwerk. Hulle wys hulle voorkeure deur die toekenning van 'n rangorde van 'n aantal van verskillende kombinasies van eienskap-vlakke om nuttigheidswaardes vir die eienskappe te gee. Ses verteenwoordigende kampe (drie grates en drie kleintjies) is gebruik vir 'n gestratifiseerde steekproef van 428 respondente. Die bevindings sal aanbevelings gee wat gebruik kan word. / Dissertation (MCom)--University of Pretoria, 1999. / Marketing Management / MCom / Unrestricted
47

The presence of persistent organic pollutants and heavy metals in sediment samples from rivers in the Kruger National Park / Annemarie van Gessellen

Van Gessellen, Annemarie January 2015 (has links)
Since 2008, large numbers of Nile crocodile (Crocodylus niloticus) carcasses were found in the Kruger National Park (KNP), South Africa. Most of the crocodile carcasses were found in the Olifants Gorge, which is situated below the Letaba and Olifants river confluence, before the Mozambique border and Massingir Dam. The Massingir Dam is an important resource and it plays a significant role in the welfare of the local Mozambican population. Autopsies performed on the crocodiles indicated that the adipose tissue colour changed from normal white to yellow and this is usually a sign of pansteatitis. Pansteatitis is caused by lipid peroxidation in an organism and it is characterised by the lack of vitamin E. This disease is recognisable by the hardening of the fatty tissue and yellow discolouration, and is mostly associated with aquatic organisms from polluted ecosystems. There are speculations that the crocodile fatalities may be associated with the Massingir Dam that backed up into the Olifants Gorge after flooding. After the dam was reconstructed, it flooded the Olifants Gorge, causing it to act like a localised sediment trap as the water flow slowed down and as a result, caused pollutants to build-up. Sediment samples were collected from selected rivers and ponds within the KNP. These samples were analysed for selected elements, persistent organic pollutants (POPs), and polycyclic aromatic hydrocarbons (PAHs). The sediment samples were analysed in Norway for POPs and PAHs with the use of a high-resolution gas chromatography/mass spectrometry (GC/MS) and the heavy metals were analysed in South Africa with the use of inductively-coupled plasma mass spectrometry (ICP/MS). In order to identify which elements may have affected the health of the crocodiles, a series of sediment quality indices were used. These indices made it possible to determine which elements may have been involved. The order of probability of heavy metals causing harm was Se>As>Ni>Cr>Cu>I>V>Mn>Co>Fe>Cd>Hg>Zn>Pb>Ba>U. The data was compared to selected international guidelines. All the information was used to determine which of the sampled sites had the highest contamination. The sites sampled with the highest concentrations were in the Crocodile, Nkomati, Olifants, and Letaba Rivers. Concentrations of the elements, POPs, and PAHs were also quantifiable in the Olifants Gorge. The following elements (Fe, Co, Cu, Cr, Pb, V, As, and Ni) were quantified at elevated levels and may therefore have caused negative effects on the crocodiles in the Olifants Gorge. These elevated concentrations, in combination with the dramatic change in the physical environment due to the dam, could have added additional stress that may have contributed to the observed crocodile mortalities in the Olifants Gorge. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015
48

The presence of persistent organic pollutants and heavy metals in sediment samples from rivers in the Kruger National Park / Annemarie van Gessellen

Van Gessellen, Annemarie January 2015 (has links)
Since 2008, large numbers of Nile crocodile (Crocodylus niloticus) carcasses were found in the Kruger National Park (KNP), South Africa. Most of the crocodile carcasses were found in the Olifants Gorge, which is situated below the Letaba and Olifants river confluence, before the Mozambique border and Massingir Dam. The Massingir Dam is an important resource and it plays a significant role in the welfare of the local Mozambican population. Autopsies performed on the crocodiles indicated that the adipose tissue colour changed from normal white to yellow and this is usually a sign of pansteatitis. Pansteatitis is caused by lipid peroxidation in an organism and it is characterised by the lack of vitamin E. This disease is recognisable by the hardening of the fatty tissue and yellow discolouration, and is mostly associated with aquatic organisms from polluted ecosystems. There are speculations that the crocodile fatalities may be associated with the Massingir Dam that backed up into the Olifants Gorge after flooding. After the dam was reconstructed, it flooded the Olifants Gorge, causing it to act like a localised sediment trap as the water flow slowed down and as a result, caused pollutants to build-up. Sediment samples were collected from selected rivers and ponds within the KNP. These samples were analysed for selected elements, persistent organic pollutants (POPs), and polycyclic aromatic hydrocarbons (PAHs). The sediment samples were analysed in Norway for POPs and PAHs with the use of a high-resolution gas chromatography/mass spectrometry (GC/MS) and the heavy metals were analysed in South Africa with the use of inductively-coupled plasma mass spectrometry (ICP/MS). In order to identify which elements may have affected the health of the crocodiles, a series of sediment quality indices were used. These indices made it possible to determine which elements may have been involved. The order of probability of heavy metals causing harm was Se>As>Ni>Cr>Cu>I>V>Mn>Co>Fe>Cd>Hg>Zn>Pb>Ba>U. The data was compared to selected international guidelines. All the information was used to determine which of the sampled sites had the highest contamination. The sites sampled with the highest concentrations were in the Crocodile, Nkomati, Olifants, and Letaba Rivers. Concentrations of the elements, POPs, and PAHs were also quantifiable in the Olifants Gorge. The following elements (Fe, Co, Cu, Cr, Pb, V, As, and Ni) were quantified at elevated levels and may therefore have caused negative effects on the crocodiles in the Olifants Gorge. These elevated concentrations, in combination with the dramatic change in the physical environment due to the dam, could have added additional stress that may have contributed to the observed crocodile mortalities in the Olifants Gorge. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015
49

Phylogenetic analysis of plant community assemblages in the Kruger National Park, South Africa

16 August 2012 (has links)
D.Phil. / What underlies species distribution and species coexistence has long been of key interest in community ecology. Several methods and theories have been used to address this question. However, it still remains a controversial debate. The recent development of plant DNA barcodes with possibility of merging phylogeny with ecology brings high expectation in uncovering the processes underlying community assemblages. Previous works that used molecular approach in community ecology focused mainly on rainforests. Using a phylogenetic approach, this study brings novel understandings about savanna ecology, especially regarding how megaherbivores impact plant community composition. The Kruger National Park (KNP) is one of the world’s largest reserves, but less studied from a phylogenetic perspective. A DNA database of 445 DNA sequences (plant DNA barcodes, rbcLa + matK) was generated for the woody plants of the KNP. This database proves reliable in reconstructing the phylogeny of Angiosperms of the park. Based on this phylogeny, the present study characterised plant community composition, and investigated how megaherbivores influence this composition. Results indicate that plant communities in the KNP are not neutral, i.e. they are more clustered than expected under various null models. This suggests that ecological forces, most likely habitat filtering may be playing key role in dictating community structure in the KNP. The KNP is well-known for its richness in megaherbivores. The contribution of these animals to the current shape of plant community structures was therefore further investigated. Where megaherbivores have been excluded, plant diversity decreases, but shifts in plant community structure are contingent upon the initial community composition, suggesting that herbivory might be important filter that drives the clustering pattern observed.
50

Review of the ecological implications of artificial waterhole closures in the Kruger National Park and the effect thereof on tourism

22 June 2011 (has links)
M.Sc. / Boreholes in the Kruger National Park (KNP) was at first developed to increase the number of animals that were at low densities because of poaching, diseases, fencing and low permanent water availability. This development of artificial waterholes without managerial measures or knowledge of possible consequence led to negative impacts on the environment. These included that the higher concentration of herbivores around artificial waterholes led to a change in vegetation; secondary vegetation growth did not support the feeding habits of water dependent species; the infiltration rate of water in the soil surrounding waterholes changed and animal distribution patterns also changed, in turn changing the predatory base. Due to the above the KNP developed a new water policy. The policy states that all artificial waterholes that are open should be part of natural ecosystem principles. This led to the closure of many artificial waterholes that did not conform to the requirements of the new water policy. This study aimed to determine the ecological implications of artificial waterholes and whether tourism will be affected by the closure of these artificial waterholes. The following two hypothesis were thus tested in this project: i) Artificial waterholes have ecological implications on the environment. ii) The closure of artificial waterholes will have a negative response from tourists and thus affect tourism to the KNP. The results from this project indicated that both these hypothesises can be accepted as the available literature clearly showed that artificial waterholes do have a negative impact on the environment and that the majority of the tourist questioned asked for the waterholes to be opened again. The latter reaction was mainly due to the tourist‟s concern that the animals will suffer and die without water. Furthermore the visitors are concerned they won‟t see animals anymore. This result can partly be due to the low awareness of the visitors on the subject. No effort was made to communicate these decisions, and the reasons it‟s based on, to the public. Although a certain number of artificial waterholes were closed according to the new KNP policy, it is still important to keep a number open due to fact that KNP is not a natural system. It is suggested however that the closure of the artificial waterholes take place differently, following a principle of rotational opening and closing of patches of waterholes to allow recovery of vegetation and facilitate migration between waterholes.

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