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1
Gilfillan, Geoffrey. "An investigation of the olfactory and multi-modal communication of African lions (Panthera leo) in the Okavango Delta, Botswana." Thesis, University of Sussex, 2017. http://sro.sussex.ac.uk/id/eprint/70332/.
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Communication is a crucial mechanism at the basis of animal social behaviour and likely to be of central importance in facilitating the evolution of complex animal societies. This thesis aims to expand our knowledge of the olfactory, vocal and multi-modal communication of wild African lions. Much of our understanding of lion behaviour originates from studies in East Africa, yet the ancestral lion may have been a wetland specialist in habitats such as the Okavango Delta. Here I first employ an established playback design to test whether lions can determine the number of conspecifics calling in large vocal choruses, demonstrating that the upper limit for lions to assess the number of simultaneous callers is three, matching the ability of humans performing a similar task. I then use a novel playback experiment to demonstrate that lions are capable of cross-modal processing of information on individual identity; an ability originally thought to be unique to humans and not previously demonstrated in wild animal populations. Next, I provide a novel and detailed investigation into the olfactory communication of lions. First I analyse the scent-marking of lions and the responses of group members to marks, and demonstrate that chemical signals may play an important role in the social lives of prides. I then use a scent presentation experiment to test the function of urinary scent-marks in communication within and between prides, determining that lion urine signals the social group and sex of the depositor and may be important for sexual assessment and territory defence. Overall this thesis significantly advances our knowledge of the vocal and olfactory communication of African lions, and provides the first evidence that lions are capable of cross-modal individual recognition during communication between conspecifics. Together these results highlight that olfactory and multi-modal communication are important for lions, despite being previously overlooked.
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Broekhuis, Femke. "Niche segregation by cheetah (Acinonyx jubatus) as a mechanism for co-existence with lion (Panthera leo) and spotted hyaena (Crocuta crocuta)." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:b49a3d35-1b89-4c38-91c5-10330589b2be.
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Intraguild competition and predation have been recognised as important ecological factors influencing the population dynamics of carnivores. The effects of these interactions are often asymmetrical due to a size-related dominancy hierarchy. However, it has been suggested that competitively subordinate carnivores can minimise the costs of predation and competition through spatial and temporal avoidance. Here I investigate the ecological and behavioural mechanisms by which cheetahs (Acinonyx jubatus) coexist with competitively stronger lions (Panthera leo) and spotted hyaenas (Crocuta crocuta). Fieldwork was carried out in the Okavango Delta, northern Botswana, between October 2008 and August 2011. A total of 20 Global Positioning System (GPS) radio-collars were fitted on all known cheetahs (n=6), lion prides (n=5) and spotted hyaena clans (n=6) in the study area (approx. 3 000 km2). Pre-programmed radio-collars recorded locations and activity continuously for each individual and these data were complemented with direct behavioural observations. Cheetah data were analysed with respect to the temporal and spatial likelihood of encountering lions and spotted hyaenas. Results suggest that the response to the risks posed by other predators is species-specific, habitat-specific and dependent on the immediacy of the risk. Resource partitioning was not the main mechanism for coexistence as cheetahs overlapped extensively with lions and spotted hyaenas in time, space and habitat use. Instead, cheetahs adjusted their spatial distribution in response to immediate risks or adapted their habitat use depending on their vulnerability (e.g. behaviours such as feeding or with differing levels of moonlight at night). In general, cheetah temporal and spatial distribution is a hierarchal process, firstly driven by resource acquisition and thereafter fine-tuned by predator avoidance. In addition, habitat heterogeneity seemed to be key in facilitating coexistence. Understanding the behavioural mechanisms that interacting apex predators adopt to regulate these negative interactions could be crucial to carnivore conservation, especially as human-related habitat loss is forcing species into ever smaller areas.
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Wohland, Pia Nicole. "Ecosystem fluxes in the Okavango Delta, Botswana." Thesis, University of Leeds, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.445846.
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Milzow, Jan Christian. "Hydrological and sedimentological modelling of the Okavango Delta Wetlands, Botswana /." Zürich : ETH, 2008. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=18058.
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Bonyongo, Mpaphi Casper. "The ecology of large herbivores in the Okavango Delta, Botswana." Thesis, University of Bristol, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.409528.
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Plavsic, Militsa Justine. "Small mammal responses to fire in the Okavango Delta, Botswana." Thesis, University of Cambridge, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.612817.
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Mmualefe, Lesego Cecilia. "Sample preparation for pesticide analysis in water and sediments a case study of the Okavango Delta, Botswana." Thesis, Rhodes University, 2010. http://hdl.handle.net/10962/d1005006.
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This thesis presents a first ever extensive analysis of pesticides in water and sediments from the Okavango Delta, Botswana, employing green sample preparation techniques that require small volumes of organic solvents hence generating negligible volumes of organic solvent waste. Pesticides were extracted and pre-concentrated from water by solid phase extraction (SPE) and headspace solid phase microextraction (HS-SPME) while supercritical fluid extraction (SFE) and pressurized fluid extraction (PFE) were employed for sediments. Subsequent analysis was carried out on a gas chromatograph with electron capture detection and analytes were unequivocally confirmed by high resolution mass spectrometric detection. Hexachlorobenzene (HCB), trans-chlordane, 4,4′-DDD and 4,4′-DDE were detected after optimized HS-SPME in several water samples from the lower Delta at concentrations ranging from 2.4 to 61.4 μg L-1 that are much higher than the 0.1 μg L-1 maximum limit of individual organochlorine pesticides in drinking water set by the European Community Directive. The same samples were cleaned with ISOLUTE C18 SPE sorbent with an optimal acetone/n-hexane (1:1 v/v) mixture for the elution of analytes. No pesticides were detected after SPE clean-up and pre-concentration. HCB, aldrin and 4, 4‟-DDT were identified in sediments after SFE at concentration ranges of 1.1 - 30.3, 0.5 – 15.2 and 1.4 – 55.4 μg/g, respectively. There was an increase of pesticides concentrations in the direction of water flow from the Panhandle (point of entry) to the lower delta. DDE, fatty acids and phthalates were detected after PFE with optimized extraction solvent and temperature. The presence of DDT metabolites in the water and sediments from the Okavango Delta confirm historical exposure to the pesticide. However their cumulative concentration increase in the water-flow direction calls for further investigation of point sources for the long-term preservation of the Delta. The green sample preparation techniques and low toxicity solvents employed in this thesis are thus recommended for routine environmental monitoring exercises.
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Bonyongo, Mpaphi Casper. "Vegetation ecology of the seasonal floodplains in the Okavango Delta, Botswana." Diss., Connect to this title online, 1999. http://upetd.up.ac.za/thesis/available/etd-03012007-103712/.
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Songhurst, Anna Catherine. "Competition between people and elephants in the Okavango Delta Panhandle, Botswana." Thesis, Imperial College London, 2012. http://hdl.handle.net/10044/1/9549.
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The general objective of this study was to gain a greater understanding of the complexities of the competition between people and elephants, focusing on elements that can be investigated in the short term and could aid in devising effective mitigation and management strategies. Specifically, I aimed to a) determine the current elephant population numbers and growth rate in the study area and investigate how reliable aerial survey estimates are; b) monitor the extent of human-elephant conflict (HEC) incidents and compare community based monitoring techniques to a top-down government approach; c) determine key drivers of elephant crop-raiding and explore how spatial autocorrelation affects such data; d) investigate how elephant movements are affected by human habitat modifications, and; e) investigate rural farmers' attitudes towards elephants and compare perceived human-elephant conflict to actual measurable levels of elephant crop damage. My findings show that combinations of social and ecological factors are involved in shaping competition between people and elephants. A multi-disciplinary approach to investigations is, therefore, needed to fully understand such competition and resulting conflicts. Contributory factors to HEC identified in this study include: actual and perceived conflict levels; farmer vulnerability to risk and available coping strategies; susceptibility of crops to elephant foraging, which affects both actual and perceived conflict levels; methods used to measure damage; natural and modified behaviour of people and elephants affecting resource and spatial use as well as how each species reacts to living in close proximity to each other; and human feelings and perception towards elephants and the situation, which are influenced by an array of socio-economic factors. To be successful, effective conflict resolution and management strategies will, therefore, require consideration of short and long term dynamics, as well as a combination of mitigation approaches that consider all elements affecting conflict extent.
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Mpofu, Christopher. "Assessment of organochlorine pesticide residues in fish samples from the Okavango Delta, Botswana." Thesis, Rhodes University, 2011. http://hdl.handle.net/10962/d1006707.
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This thesis presents an evaluation of the dispersive solid-phase extraction (d-SPE) method referred to as the quick, easy, cheap, effective, rugged and safe (QuEChERS) method for the determination of four organochlorine pesticide residues in fish samples. The pesticides investigated in this study were o, p′-DDT, p, p′-DDE, aldrin and dieldrin. The combined use of Gas Chromatography with an Electron Capture Detector (GC-ECD) and sensitive Time of Flight (TOF) mass detector facilitated the identification of the target analytes. In the absence of certified reference material, the overall analytical procedure was validated by systematic recovery experiments on spiked samples at three levels of 2, 5 and 10 ng/g. The targeted compounds were successfully extracted and their recovery ranged from 76 to 96% with relative standard deviations of less than 13%. The optimum QuEChERS conditions were 2g of fish powder, 10 ml acetonitrile and 1 min shaking time. The optimal conditions were applied to assess the levels of chlorinated pesticides in blunt-tooth catfish (Clarias ngamensis), tigerfish (Hydrocynus vittatus), Oreochromis andersonii and red-breasted tilapia (Tilapia rendalli) from the Okavango Delta, Botswana. Dieldrin, p, p′-DDE and aldrin were detected in all the analysed samples with a concentration range of 0.04 – 0.29, 0.07 – 0.33, 0.04 – 0.28 and 0.03 – 0.24 ng/g per dry weight in O. andersonii, C. ngamensis, T. rendalli and H. vittatus respectively. These concentrations were below the US-EPA 0.1 μg/g allowable limit in edible fish and the Australian Maximum Residue Limit (MRL) of 50 - 1000 ng/g in fresh fish. DDT was not detected in all the fish species investigated. The mean lipid content recorded in the fish samples were 1.24, 2.16, 2.18 and 4.21% for H. vittatus, T. rendalli, O. andersonni and C. ngamensis respectively. No systematic trend was observed between fish age and pesticide levels in fish. Acetylcholinesterase (AChE) activity assays were performed to assess the effects of organochlorine pesticides in Clarias ngamensis. The enzyme activity recorded in Clarias ngamensis from the Okavango Delta and the reference site was 12.31 μmol of acetylcholine iodide hydrolysed/min/g brain tissue. The enzyme activity remained the same indicating no enzyme inhibition. The conclusions drawn from this study are that the QuEChERS method is applicable for the determination of organochlorine pesticide residues in fish matrices. The fish from the Okavango Delta are safe for human consumption.
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Bokhutlo, Thethela. "Life-history and stock assessment of Clarias Gariepinus in the Okavango Delta, Botswana." Thesis, Rhodes University, 2012. http://hdl.handle.net/10962/d1005142.
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Large catfishes (Clarias gariepinus & Clarias ngamensis) are not exploited commercially in the Okavango Delta, Botswana. They however constitute a large proportion of the gill net fishery catch (23 %) albeit as by-catch, coming second after cichlids (70 %). Monthly experimetal gill net sampling over 8 years showed that C. gariepinus was the most abundant species in the Okavango Delta by mass making up 37 % of the catch composition by fresh weight. Despite the relatively high abundance of C. gariepinus in the Okavango Delta, its status has never been fully assessed. For this reason, this study aimed to assess the status of C. gariepinus in the Okavango Delta with the particular goal to determine if the species could support a directed commercial gill net fishery. Investigation of the effects of the flood pulse on abundance of C. gariepinus showed that variability in water levels was the major driver of population abundance for this species. Three biological variables: (1) catch per unit effort (CPUE); (2) % catch composition and (3) Shannon's diversity index (H') exhibited a negative and significant relationship with the flood index within a year. The variation in these variables was statistically significant between months. There was a weak positive relationship between water levels and the biological variables between years suggesting increase in productivity of the system at high water levels without a lag period. Age and growth were determined using sectioned otoliths. Edge analysis showed that growth zone deposition occurred during the drawdown period in summer when water temperature and day length were increasing. The maximum recorded age was 15 years. Growth of this species was best described by the linear models (y = 21.50x + 427.39 mm LT; r² = 0.35) for females and (y = 23.79x + 440.83 mm LT; r² = 0.38) for males. The von Bertalanffy growth model described growth as Lt = 10000(1- exp(-0.002(t + 18.07))) mm LT for combined sexes Lt = 10000(1- exp( -0.002(t + 18.50))) mm LT , for females and Lt =908(1-exp(-0.076(t+7.95)))mmLT for males. Age at 50 % maturity was attained in the first year of life. Spawning occurred throughout the year with an apparent peak between November and April. The mean total annual mortality rate (Z) was 0.25 per year. The mean annual natural mortality rate (M) was 0.20 per year and fishing mortality (F) was calculated at 0.05 per year. The life history strategy of C. gariepinus was in between the periodic and opportunistic strategies. Therefore management of this species should be aimed at maintaining a healthy adult population and age structure. Since a large portion of the Okavango Delta is already protected and most other parts are also inaccessible to fishers there are enough spatial refugia for the species and the status quo should be maintained. Under this scenario, there is no need for regulation of the current mesh sizes because the species is harvested after maturity and replenishment of exploited populations will always occur from other parts of the system. Per recruit analyses indicate that the current fishing mortality maintains spawner biomass at levels greater than 90 % of pristine levels. Therefore a commercial fishery may be established using mesh 93 mm to maximize yield with a rotational harvesting strategy. Close monitoring is essential to ensure that re-colonization of overexploited habitats does indeed occur. Recreational angling and commercial gill net fishing need to be separated on a spatial and temporal scale during the feeding run to minimize potential conflicts.
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Bennitt, Emily. "The ecology of African buffalo (Syncerus caffer) in the Okavango Delta, Botswana." Thesis, University of Bristol, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.573418.
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Abstract Wilderness areas across the globe are under rising threat from increasing anthropogenic activities, the effects of which are likely to be exacerbated by climate change. The Okavango Delta is a relatively pristine wetland system that supports abundant wildlife and provides livelihoods for many local communities. This ecosystem is governed by an unusual dual moisture regime, which is responsible for seasonal changes in resource availabilities, and corresponding shifts in herbivore spatial patterns and population demographics. African buffalo form an important part of the system, so understanding their ecological requirements is essential 'for the conservation of this unique area. My results showed that the extent and location of buffalo home ranges depended on the availability of water and forage, as did their habitat use. Forage abundance and palatability were the main characteristics sought by grazing buffalo, whereas shade and sparse grass were preferred for resting; these trends were apparent at multiple spatial scales, both within and between habitat types. Buffalo displayed an unusual social system: highly dynamic herds occupied shared ranges and, within my study area, formed two sub-populations with divergent migratory strategies; these were probably driven by differing resource availabilities and levels of anthropogenically-induced spatial restriction. The sub-populations shared similar critical seasonal habitats, and showed comparable population demographics and body condition; neither appeared to be under nutritional stress, and their seasonal ranges provided access to forage with similar characteristics. High levels of heterogeneity at several spatial scales appeared to be the most important ecological factor for a sustainable buffalo population. My results highlighted the importance of identifying and protecting critical seasonal resources, and the movement routes linking them, for the conservation of highly mobile large herbivores and the ecosystems that support them, particularly in the light of unpredictable future environmental changes.
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Murray-Hudson, Mike. "Floodplain vegetation responses to flood regime in the seasonal Okavango Delta, Botswana." [Gainesville, Fla.] : University of Florida, 2009. http://purl.fcla.edu/fcla/etd/UFE0024728.
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Lehmensiek, May. "Evaluation of tourism in the Okavango Delta in Botswana using environmental accounting." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0008842.
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Mbongwe, Bontle. "Fate and persistence of DDT and its metabolites in the Okavango Delta, Botswana." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ67838.pdf.
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Shacks, Vincent. "Habitat vulnerability for the Nile crocodile (Crocodylus niloticus) in the Okavango Delta, Botswana." Thesis, Link to the online version, 2006. http://hdl.handle.net/10019/1651.
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Merron, Glen Steven. "The ecology and management of the fishes of the Okavango Delta, Botswana, with particular reference to the role of the seasonal floods." Thesis, Rhodes University, 1991. http://hdl.handle.net/10962/d1005112.
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The Okavango is a vast inland delta system in northern Botswana which receives an annual flood from the highlands of southern Angola. There are distinct communities of fish in the Okavango which can be separated from each other by the physical characteristics of the different habitat types with which they co-evolved. This thesis provides an account of the biology and ecology of selected fish species in the Okavango Delta. Their response to the annual flood regime, and the environmental factors which limit their distribution and abundance, are examined. The thesis emphasizes the importance of water fluctuations in determining the nature of the fish fauna and the reaction of the fishes in terms of community structure, movements, breeding, predator-prey interactions and feeding. Four major ecotones were studied in the Okavango Delta. In the riverine floodplain and perennial swamp ecotones a higher species diversity was recorded than in the seasonal swamp and drainage rivers ecotones where diversity was lowest and comprised mainly of smaller fish species. A greater variety of habitat types was associated with the riverine floodplain and perennial swamp relative to the seasonal swamp and drainage rivers. The variety of habitat types between ecotones is associated with the degree of flood inundation in the respective ecotones. During the course of this study, annual recruitment of fish into the drainage rivers was from refugia in the seasonal swamp whereas the greatest degree of lateral and longitudinal movement was in the riverine floodplain and perennial swamp. Movement was in response to both biological requirements, such as availability of food and spawning sites, and physical features of the environment, such as the changing water depth. The total catch per unit effort (CPUE) of fish throughout the year was more constant in the riverine floodplain and perennial swamp than in the seasonal swamp and drainage rivers where CPUE fluctutated widely. An increase in CPUE during the duration of this study was apparent and related to the magnitude of the annual flood. In contrast to most other African wetlands, the arrival of the annual flood in the Okavango Delta coincides largely with the dry winter months. This situation presented an opportunity to compare the influence of floods and water temperature on the reproductive biology of the selected fish species. The results show a definite pattern and indicate that both the flood cycle and increased water temperatures greatly influence the breeding cycles of the selected species. The tilapia Oreochromis andersonii exhibited a considerable degree of phenotypic plasticity. Fish from the seasonally inundated areas showed a smaller mean size, egg size and larger number of eggs relative to fish in the perennially flooded areas. The size at sexual maturity was also smaller. These different reproductive characteristics exhibited by O. andersonii are dependent on the degree of water retention in the different habitats. The fishes of the Okavango have adopted other reproductive strategies to survive the changing environmental conditions brought about by an annual flood cycle. These strategies include the construction of foam nests, as described for Hepsetus odoe, for guarding the young and to provide an oxygen-rich environment. Two main non-piscivorous feeding pathways were identified in the Okavango. These are a detritus pathway based on dead plant and animal material, and an epiphyte pathway, based on algae and invertebrates that are attached to plant stems. Seasonal changes in diet in relation to the annual flood were recorded. The most dramrtic change was demonstrated by the catfish Clarias gariepinus which congregates in mass aggregations in the northern regions of the Delta and hunt in packs. Pack-hunting by catfish is a regular response to the annual fluctuations in water level. It is my conclusion that the main flow of biotic and abiotic stimuli within the Okavango Delta originates from the relatively hydrologically stable riverine floodplain and perennial swamp ecotones to the widely fluctuating seasonal swamp and drainage rivers ecotones. The relatively stable ecotones allow a diverse and biotically interdependent fish community to develop, whereas the widely fluctuating seasonal swamp and drainage rivers ecotones are characterized by a less diverse and interdependent fish community. The degree of abiotic and biotic interdependence among fish in an ecotone is very important for the long term management of the Okavango Delta. Potential developers have to determine whether the effect of a given action by man is likely to result in a long term disturbance or merely in an elastic recoil to a more or less similar state. Recommendations are made on the conservation and management of Okavango fishes taking into account the ecological characteristics of the delta.
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McCarthy, Jenny. "Remote sensing for detection of landscape form and function of the Okavango Delta, Botswana." Doctoral thesis, KTH, Civil and Environmental Engineering, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3314.
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Matswiri, Gertrude Mamotse. "Two in one: explaining the management of the Okavango Delta World Heritage Site, Botswana." Master's thesis, University of Cape Town, 2017. http://hdl.handle.net/11427/27483.
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Because of their outstanding universal significance, World Heritage sites are worthy of special protection by the international and local communities. They obtain this status after being listed under the UNESCO 1972 Convention Concerning the Protection of the World Cultural and Natural Heritage. In previously colonised regions such as Africa, the conservation and management of World Heritage is based on international laws and modern management systems introduced after conquest. However, the process protects mostly the universal values on which the inscription of the site was based. This often marginalises local values and local management systems which are important to local communities. It also alienates local communities from their heritage which they have protected for many years. This research explores the relationship between modern and traditional management systems in the Okavango Delta Natural World Heritage site. It will focus on understanding the local values of the site, the current management system and traditional practices of the local communities. The expected outcome is to develop a syncretic management system influenced by the traditional and the modern. It is hoped that such a system will not privilege one type of value over others.
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Pastier, Anne-Morwenn. "The Okavango delta through the deformation of its surface : multi-proxy approach from hydrology to tectonics." Thesis, Rennes 1, 2018. http://www.theses.fr/2018REN1B004/document.
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Le Delta de l'Okavango est un système endorhéique formant un cône alluvial dans la dépression du Kalahari. L'écosystème y est rythmé par une crue annuelle en provenance de l'Angola et entravée par l'escarpement des failles normales du graben de l'Okavango. Ce régime annuel est très variable, car la répartition de la crue annuelle diffère tous les ans. À plus grande échelle temporelle, du millénaire au Ma, l'endorhéisme du Delta peut varier entre des marais (actuel), un mega-lac ou perdre son caractère endorhéique (rivière). Les processus pouvant contrôler ces variations de régime sont 1) l'hydrologie du système, 2) l'activité des failles du graben, 3) l'apport sédimentaire et 4) l'écosystème. Cette étude apporte des contraintes quantifiées éclairant deux de ces processus à travers l'observation de la déformation de la surface terrestre par l'enregistrement de stations GPS permanentes. Le signal observé est annuellement impacté par la charge hydraulique résultant de la saison des pluies, et inter-annuellement par les variations de cette charge, ainsi que l'activité tectonique du graben. Les satellites GRACE fournissent un enregistrement quasi-continu de la variation du stock d'eau continentale, rendant possible la modélisation de la déformation élastique de la surface terrestre sous l'effet de cette charge. Le signal de déformation ainsi modélisé est comparable au signal saisonnier enregistré, validant les données satellitaires GRACE et révélant un important aquifère dans le bassin de l'Okavango. GRACE fournit ainsi un nouveau proxy permettant de suivre l'évolution de l'aquifère, et de valider le modèle hydrologique calibré précédemment pour le bassin. Les variations inter-annuelles d'eau souterraine dans le bassin validées par GRACE confirment le rôle de tampon des variations climatiques joué par l'aquifère sur la modulation des variations climatiques. La phase des variations du stock d'eau met de plus en évidence un effet de seuil dans la recharge de ce stock, en fonction de l'intensité des premières pluies. La faible résolution spatiale des variations du stock d'eau continental fournie par GRACE peut finalement être mieux contrainte par un examen plus détaillé des signaux GPS dans le bassin. Les vitesses de déformation horizontales de part et d'autre du graben révèlent une déformation tectonique faible sur l'ensemble du graben, de 1 mm/an exclusivement décrochante dextre. Une si faible déformation exclut une influence significative de l'activité tectonique et sismique du graben sur la variabilité de la distribution de la crue. Cette déformation observée remet en question le modèle géodynamique admis dans la région, soit une phase précoce de rifting liée à la propagation d'une branche SW du Rift Est-Africain. Un recensement des nombreuses études géophysiques réalisées dans la région dans la dernière décennie et un réexamen de la sismicité de l'Afrique australe n'amène aucune preuve significative de rifting dans le graben de l'Okavango. Un autre modèle géodynamique pour l'Afrique australe est proposé, basé sur l'accommodation lointaine de la déformation associée à l'ouverture à taux différentiels du Rift Est-Africain et le déplacement du craton du Kalahari par rapport au reste de la plaque nubienneThe Okavango Delta is an endorheic system forming an alluvial fan in the Kalahari depression. The local ecosystem is paced by the annual flood coming from the Angolan highlands, blocked downstream by the normal faults scarps of the Okavango graben. This annual regime is highly variable, with the spatial distribution of the flood differing every year. At the geological time scale, from millenary to mega-annual, the Delta's endorheism can also vary between wetlands (current regime), mega-lake or loose its endorhism to turn into a river. Processes driving these regime variations are 1) the hydrological system, 2) the faulting of the graben, 3) the sedimentary input and 4) the ecosystem. This study brings quantitative constraints regarding two of these processes through the deformation of the Earth's ground surface monitored by permanent GPS stations. The observed signal is impacted seasonally by the hydrological loading resulting from the rainy season, and inter-annually by the variations of the terrestrial water storage, as well as the tectonic activity of the graben. GRACE satellites provide a quasi-continuous record of the variations of the Earth's continental water storage, allowing the modelling of the elastic deformation imposed on the Earth's crust by loading. The resulting modelled deformation signal is well correlated to the observed seasonal signal, hence validating the GRACE data products and revealing a large aquifer in the Okavango basin. GRACE thus provides a new proxy to monitor the evolution of water storage, and to validate more robustly the hydrological model calibrated for the basin. The variations in terrestrial water storage (TWS) in the basin validated by GRACE confirm the buffer effect of the aquifer in the modulation of climatic variations. The phase of the TWS variations moreover highlights a threshold in the recharge of TWS during the rainy season, depending on the intensity of the first rains. Finally, the poor spatial resolution of TWS variations provided by GRACE can be further constrained by a detail examination of the GPS signals in the basin. Horizontal displacements rates across the graben reveal a low tectonic deformation rate, of 1 mm/yr, exclusively along a dextral strike-slip component. Such a low deformation rate excludes a significant influence of the graben faulting on the variability of the flood distribution. The observed deformation calls into question the current geodynamic model for the area, i.e. incipient rifitng due to the propagation of a southwestern branch of the East African Rift System. A review of the numerous geophysical studies in the study area over the last decade, as well as a re-examination of the seismic data in southern Africa does not provide significant evidence for rifting in the Okavango graben. An alternative geodynamic model is proposed, based on the far-field accommodation of the deformation resulting from the differential extension rates in the Rift Valley, and the displacement of the Kalahari craton relative to the Nubian plate
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Mmopelwa, Gagoitseope. "The value of the Okavango delta a natural resource accounting approach /." Thesis, Pretoria : [s.n.], 2006. http://upetd.up.ac.za/thesis/available/etd-12072006-152953.
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Marazzi, L. "Biodiversity and biomass of algae in the Okavango Delta (Botswana), a subtropical flood-pulsed wetland." Thesis, University College London (University of London), 2014. http://discovery.ucl.ac.uk/1459199/.
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In freshwater bodies algae provide key ecosystem services such as food and water purification. This is the first systematic assessment of biodiversity, biomass and distribution patterns of these aquatic primary producers in the Okavango Delta (Botswana), a subtropical flood-pulsed wetland in semiarid Southern Africa. This study delivers the first estimate of algal species and genera richness at the Delta scale; 496 species and 173 genera were observed in 132 samples. A new variety of desmid (Chlorophyta) was discovered, Cosmarium pseudosulcatum var. okavangicum, and species richness estimators suggest that a further few hundred unidentified species likely live in this wetland. Rare species represent 81% of species richness and 30% of total algal biovolume. Species composition is most similar within habitat types, thus varying more significantly at the Delta scale. In seasonally inundated floodplains, algal species / genera richness and diversity are significantly higher than in permanently flooded open water habitats. The annual flood pulse has historically allowed more diverse algal communities to develop and persist in these shallower and warmer environments with higher mean nutrient levels and more substrata and more heterogenous habitats for benthic taxa. These results support the Intermediate Disturbance Hypothesis, Species-Energy Theory and Habitat Heterogeneity Diversity hypotheses. Higher algal biodiversity supports higher algal biomass in the floodplains, where species form three-dimensional communities of attached and periphytic algae requiring more nutrients than phytoplankton assemblages. Multivariate analyses demonstrate that habitat type, flooding frequency and conductivity most importantly influence the relative abundance of algal species, genera and phyla in the Okavango Delta. This study’s findings highlight how the preservation of water level fluctuations and habitat heterogeneity is crucial to maintaining biodiverse and thus resilient food webs in this unique ecosystem which faces increasing anthropogenic threats, such as global warming and upstream water abstraction plans.
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Vitale, Jessica. "The olfactory behaviour of spotted hyaenas (Crocuta crocuta) and sympatric mammals in the Okavango Delta, Botswana." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/48855/.
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Understanding the natural behaviour and coexistence of species is important for the conservation of intact ecosystems, and behavioural studies can enhance our knowledge of processes such as communication and competition. I investigated the social dynamics and scent-marking behaviour of spotted hyaenas (Crocuta crocuta), and the occurrence of interspecific olfactory eavesdropping among African mammals, within the Okavango Delta ecosystem of Botswana. First, social network analysis found that the hyaena population was comprised of five main clans that maintained territories but whose home ranges overlapped considerably. Scavenging at large carcasses involved associations between individuals from different clans and resulted in relative tolerance toward territorial intruders. Second, observations of communal latrine use found that latrines are likely involved in territorial advertisement by hyaena clans, and cyclical patterns of latrine growth and decline were linked to annual rainfall. Third, a translocation experiment showed that hyaena scats appear to be less important for hyaena communication than other cues associated with latrines, especially as hyaenas did not differ in their behaviour towards scat originating from latrines located in resident versus non-resident clan home ranges. Heterospecific mammals investigated, scent-marked, and were vigilant at hyaena latrines, suggesting a potential function for hyaena latrines in interspecific eavesdropping and/or communication. Fourth, a urine presentation experiment found that the investigation of sympatric predator urine by African mammals stimulated vigilance behaviour, suggesting that olfactory signals provide information about predation risk. Hyaenas exhibited context-specific differences in behaviour towards predator urine: they were more likely to investigate urine samples alongside indicators of predator activity (i.e. carrion odour, carcasses) and were most likely to exhibit vigilance at carcasses when exposed to urine from lions and wild dogs. This study greatly enhanced our understanding of spotted hyaena behaviour within the Okavango Delta, an important ecosystem for the conservation of African large predators. Furthermore, this study provided the first experimental evidence of the role of hyaena scats in intraspecific communication and interspecific olfactory eavesdropping at latrines. My research findings regarding the population’s clan structure and home ranges will form the foundation for subsequent investigation into human-wildlife conflict in the study area. Furthermore, the results from two scent experiments shed light on the potential importance of olfactory signals for mediating interspecific interactions among African mammals, particularly among large predators.
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Evans, Kate Elizabeth. "The behavioural ecology and movements of adolescent male African elephant (Loxodonta africana) in the Okavango Delta, Botswana." Thesis, University of Bristol, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.431629.
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Dikgola, Kobamelo. "Spatial and temporal variation of inundation in the Okavango Delta, Botswana; with special reference to areas used for flood recession cultivation." University of the Western Cape, 2015. http://hdl.handle.net/11394/4677.
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Philosophiae Doctor - PhDThe Okavango Delta is recognized as one of the famous inland wetlands and its sustainable use is important for socio-economic development of Botswana. The Okavango delta comprises permanent swamps, seasonal swamps, and drylands on islands within the delta and the surrounding areas, sustained by Okavango river inflows from upstream and local rainfall. TheOkavango River splits into several distributary channels within the delta. Areas which are flooded annually vary in response to varying inflows into the delta. Peak inflows into the delta occur during the February to May period. Due to the low gradient over the delta, these inflows move slowly resulting in peak outflows from the delta occurring during the June to August period. The inundated area over the entire delta increases from May until it reaches maximum inAugust and starts to decrease from September, reaching minimum inundated area in the months of December and January. The incoming flood wave into the delta and maximum inundation is out of phase with the local rainfall season.Communities living within and around the delta derive their livelihoods from tourism, hunting, fishing, livestock rearing, and crop production. Crop production is carried out on drylands and within floodplains. Some of the households take advantage of the increase in soil moisture arising from this inundation along floodplains to cultivate their crops as the floods recede. This practice is locally referred to as molapo farming which highly depends on inundation of floodplains. The availability of floodplain inundation highly depends on the magnitude of inflows into the delta and the local rainfall which are highly variable resulting in uncertainty regarding successful crop production, availability of livestock grazing areas, and uncertainty in reliance on the wetlands resources such as fishing. The uncertainty experienced in timing of extreme events which cause flooding of resulting in water reaching areas or floodplains where it is not wanted, and also uncertainity in timing of low flows, therefore water not reaching some parts of the delta.Several hydrological studies have been carried out with the aim of improving the understanding of the spatial and temporal dynamics of flows throughout the delta including predicting areas that are likely to be inundated each year. The significant gap addressed by this research is to improve the understanding of the spatial and temporal influence of magnitude and timing of flows on floodplain inundation. Local rainfall on the delta is highly variable over time and space due to its convective nature. This research also addresses the rainfall temporal and spatial variations and its implications on floodplain inundation. The knowledge about spatial extent and duration of floodplain inundation should assist in predicting each year the viability of molapo farming. Three research site, Shorobe, Tubu and Xobe are selected as case studies to understand the dynamics of floodplain inundation induced either by inflows or local rainfall. Local rainfall during the December to March period enables the crops to reach maturity. The onset of the rainy season is very important in supporting sowing of crop seeds. Local rainfall on the delta varies considerably. Aerial rainfall interpolation shows a change in rainfall magnitudes over space in different rainfall months, i.e different parts of the delta receive different rainfall magnitudes in different months of the rainy season. The spatial variation is mainly associated with the migration of the ITCZ southwards first through East Africa during October andNovember and down over Southern Africa in December to February. The movement of the ITCZ brings rainfall concentration on the northern and eastern parts of the Okavango Delta during December to January and bringing rainfall concentration to the northwestern part of the delta around February. However, rainfall spatial correlation between stations can be poor even within the first 150 km therefore implying neighboring places do not experience floodplain inundation by rainfall at the same time. The poor spatial correlation of rainfall between neighboring stations reflects the erratic nature of rainfall in the Okavango Delta characterised by localized thunderstorms. Change detection shows change points in rainfall which can be associated with ENSO episodes. A change point is identified in 1976 and 1977 which can be associated with the El Nino episodes during those years and two change points identified in 1999 and 2004 which can be associated with the La Nina episodes, therefore rainfall induced floodplain inundation can also be associated with wet and dry ENSO episodes. Rainfall does not show any significant trends except for an increasing trend on 10th percentile of Shakawe rainfall. Rainfall also does not show any cyclic behavior. Rainfall over the Okavango Delta can be divided into three unique homogenious sub-regions; sub-region 1: the northern part following the GEV probability distribution and being the region with highest rainfall amounts; sub-region 2: the lower northern and the outlet parts of the Okavango Delta following the GPA distribution with moderate rainfall; and sub-region 3: the middle part of the delta extending to the western and the eastern fringes of the delta, following the P3 distribution and having the lowest rainfall.The main characteristic that defines the Okavango Delta flows at Mohembo is its cyclic behavior. Three significant cycles are identified, close to 10, 20 and 40 years. No significant trends are identified, only a decreasing trend in minimum flows. Change points are identified in 1979 and 1988 and these can be explained by the existing cyclicity since no major land use changes have taken place in the Okavango River Basin upstream before 1989. The existence of cyclicity in Okavango River flows at Mohembo also explains the periodic wetting and drying of different floodplains in the delta. A long period of low flows was experienced from 1983 until 2003 and floodplain inundation extent was greatly reduced, more especially during the 1993-2003. During the 1993-2003 period, flows could no longer reach Maun Bridge along Thamalakne River, therefore leaving molapo floodplains around Boteti River, Gomoti River and Thaoge River to dry out. The 10 and 40 year return floods are important as they indicate the probability of a flood magnitude which has potential to result in major inundation in the Okavango Delta. Therefore, flood magnitudes with recurrence interval 10 and 40 years have high probability of occurring and can cause major floodplain inundation as they can be above the 2009 flood of 969 m3/s, which was the return of major inundation of Okavango Delta floodplains after a long period of dryness. The Ngoqa-Maunachira distributary channel of the Okavango River receives 32% of flow volumes entering the Okavango Delta at Mohembo. 12 % of the Mohembo flow volumes reach the Jao-Boro distributary whilst 1% is received by the Thaoge distributary. Therefore more inundation is experienced along the Ngoqa-Maunachira system compared to the other two. Only about 2% of the Mohembo flow volumes leave the Okavango Delta through Boteti River. Long term shifting of flow direction amongst reaches along the Okavango Delta distributaries is evident more especially along the Ngoqa-Maunachira River system. This results in shifting of inundation. Sub-surface water respond significantly to local rainfall and inflows with high soil moisture conditions retained at 60 cm and 100 cm below the ground.
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Wallace, Kevin Michael. "The feeding ecology of yearling, juvenile and sub-adult Nile crocodiles, Crocodylus niloticus, in the Okavango Delta, Botswana." Thesis, Link to the online version, 2006. http://hdl.handle.net/10019/1300.
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Bowles, Graham Robert. "The low frequency vocal communication for a herd of African elephants (Loxodonta africana) in the Okavango Delta, Botswana." Thesis, University of Bristol, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.601007.
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Since the 1980s much research has focused on the long-distance properties of elephant rumble calls. Few studies have been able to study the short-distance, intra-herd calling 01 elephants. Such understanding is imperative to the future study of their complex social behaviour. 'used a collar mounted audio and GPS data acquisition system on a captive herd of elephants based in the Okavango Delta, Botswana, to help resolve some of the logistical issues that have prevented such research in the past. My results showed that the best accuracies for predicting individual identity were achieved when using source frequency, modulation, and filter features of the call. However, comparable accuracies were still achieved when the modulation features were removed. This study also showed that similarities in calling behaviour were more influenced by social affiliations than size or age. My results also showed a framework for sub-categorising rumble calls based on their position of peak energy, degree of modulation, modulation shape, duration, and fundamental frequency. I successfully applied this method to published rumble calls, which showed that it was not limited to calls from the study herd and that such differences may be used to encode referential and motivational information. This is also the first study that measured how elephant calling behaviour is affected by seasonal and daily variations in conditions. While this study showed few changes, such aspects are important to consider in future research on elephant vocalisations. My results also showed that the contact call is not structurally defined and that call structure is more likely to be influenced by adaptations to resist sound attenuation and levels of excitement. In conclusion, I discuss how these results have improved our current understanding of low frequency calls, showing the cues receivers might use to determine various aspects about the sender and how elephants might adapt their calling to external influences. I also highlight areas of future work and discuss the advantages of the techniques used to over come some common problems faced in gathering such data and how these could be improved .
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Bourquin, Sven Leon. "The population ecology of the Nile crocodile (Crocodylus niloticus) in the panhandle region of the Okavango Delta, Botswana." Thesis, Stellenbosch : Stellenbosch University, 2008. http://hdl.handle.net/10019.1/1281.
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Thesis (PhD (Conservation Ecology and Entomology))--Stellenbosch University, 2008.The Okavango Delta, Botswana, is a unique ecosystem and this is reflected in its extraordinary biodiversity. The Nile crocodile (Crocodylus niloticus Laurenti) is the apex predator, and performs a number of vital functions in this system, making it a keystone species. The panhandle crocodile population has declined significantly over the last 80 years and is now threatened as a result of past over-exploitation and present human disturbance. In order to effectively conserve this species and in turn the health of this important region it is imperative to gain an understanding of their ecology and population dynamics. The population status of the Nile crocodile in the panhandle region of the Okavango Delta, Botswana, was assessed using a combination of capture-mark-recapture surveys, spotlight surveys and aerial surveys. The capture-mark-recapture experiment was conducted continuously from 2002 - 2006. A total of 1717 individuals, ranging in size from 136 mm – 2780 mm SVL, were captured, of which 224 animals were recaptured. Using a Bayesian technique, the total annual population in the panhandle region of the Okavango Delta was estimated to be 2 570 ± 151.06 individuals, with an adult population of 649.2 individuals with the number of breeding females estimated to be 364 individuals. It was concluded that this population cannot sustain the further harvest of breeding animals prior to the increase and stabilization of the population. Spotlight counts revealed a decline in the encounter-rate of crocodiles on the Okavango River with time, although more long-term data needs to be collected to confirm this trend. During the low-water season (September - February), 22.34 % of all crocodiles were observed, while during the flood-season only 13.34 % were observed, yielding correction factors for spotlight surveys of 4.46 (low-water) and 7.49 (high-water) for all animals in the panhandle. Two aerial surveys, conducted at the low-water and high-water peaks yielded total estimates of 588 (77.7 % of adults) during the low-water period and 350 (56.7 % of adults) during the high-water period. Correction factors of 1.28 (low-water) and 1.77 (high-water) were calculated for aerial surveys. An annual average of 50 nests was located in the panhandle, representing a 50 - 60 % decrease over the last 20 years. In regions with high human disturbance, breeding females situated their nests in hidden locations, away from accessible channels. Hatchlings exhibited elongation of the jaw in order to capture smaller prey items and morphometric shifts in jaw shape coincided with a dietary change at 400 mm SVL. The jaw became broader and deeper as animals matured, presumably in preparation for larger mammalian prey. The average growth rate of recaptured yearlings was 0.198 ± 0.116 mm.d-1 SVL and was closely correlated to the amount of time an individual spent in above-average water temperatures. Body condition (RCF) was significantly and positively correlated with a rise in water-level and negatively correlated to time spent in above-average water and air temperatures. Average RCF values were intersected when animals had spent 50 % of their time in above-average temperatures and water level. Generally crocodiles in the panhandle showed no significant sex-related differences in their sizes or the distances they travelled. The majority of recaptures (62.5 %) moved less than 500 m from the initial capture site. Adults in the panhandle occupied definite ranges, within which were preferred core areas where the majority of their time was spent. The panhandle crocodile population has declined significantly over the last 80 years, and is now threatened as a result of past over-exploitation and present human disturbance. The management of this population, including both its conservation and sustainable commercial utilisation, requires an adaptive strategy based on accurate monitoring procedures.
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Bourquin, Sven Leon. "The population ecology of the Nile crocodile (Crocodylus niloticus) in the panhandle region of the Okavango Delta, Botswana /." Link to the online version, 2007. http://hdl.handle.net/10019/813.
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Vujakovic, Peter. "Evaluation of Landsat MSS data for terrain analysis and rangeland management in the lower Okavango Delta Region, Ngamiland, Botswana." Thesis, Royal Holloway, University of London, 1986. http://repository.royalholloway.ac.uk/items/5b8660ed-eb30-48f1-acdf-85cf084d4a57/1/.
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The thesis examines the value of satellite data for terrain analysis and aspects of rangeland evaluation in Ngamiland, northern Botswana. The study area encompasses the main livestock production zone of the district. An analysis of terrain was considered integral to detailed analysis and use of satellite data for resource assessment and management. The terrain analysis was based on interpretation of multitemporal Landsat data, and aerial photography, supported by detailed field investigation. A number of classification procedures and computer based digital enhancement techniques were used to facilitate analysis and classification of the data. Terrain types were identified by relating image characteristics to terrain features, primarily vegetation patterns. Relationships between the Landsat data and various ground features related to rangeland resources were analysed. These were mainly related to vegetation parameters, including cover, structure and species composition. The most important factor investigated, was the relationship between cover values of woody vegetation and the satellite data. The results were used to develop a classification using the Landsat digital data. The usefulness of Landsat data for rangeland management, and the importance of adequate ground survey and other support data sources, is discussed in the light of results obtained.
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Kgomotso, Phemo Karen. "Global environmental agreements and local livelihoods : how the internationalisation of environmental resources shapes access to and control over wetland resources in the Okavango Delta, Botswana." Thesis, University of Sussex, 2011. http://sro.sussex.ac.uk/id/eprint/38451/.
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This thesis examines how global environmental crisis narratives and discourses have influenced environmental policy and practice in conservation programmes for the Okavango Delta, Botswana. In particular, it highlights the contested nature of biodiversity conservation and the embedded power relations in the framing, definition and crafting of solutions to the problem of biodiversity degradation at local, national and international levels. The thesis therefore examines, based on these framings, the consequences of global environmental agreements, such as the Ramsar Convention and the UN Convention on Biological Diversity, for local livelihoods in terms of access to and control over local environmental resources in the Okavango Delta. Using a political ecological conceptual lens and related literature on common pool resource management and community-based natural resource management, this thesis traces the changing perceptions, narratives and discourses relating to the Okavango Delta over time, and assesses how these have shaped changes in policy for the Delta's use and management. It specifically analyses the implementation of international programmes and their role in facilitating these changes. Through an in-depth study of dynamic human-environment interactions around fisheries and other wetland resources, this thesis shows how international interventions have not only increased conflicts but also facilitated the strict regulation of these resources. The thesis therefore analyses how framing these and other common pool resources as being of ‘international significance' alters control over them and affects the livelihood security of the local people that depend on these resources. It concludes that such restrictive conservation policies and management approaches have led to a transfer of control over wetland resources from local subsistence users to other, more powerful, commercial interests, especially those in the international tourism industry.
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Velempini, Kgosietsile M. "The Integration of Environmental Education in the Secondary School Curriculum: A Case Study of a 10th Grade Junior Secondary School Curriculum in the Okavango Delta, Botswana." Ohio University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1451919034.
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Msukwa, Chimwemwe Kanyamana. "Strategic interests in transboundary river cooperation in Southern Africa – the case of the Okavango." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/5239.
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Thesis (MA (Political Science. International Studies))--University of Stellenbosch, 2010.Bibliography
ENGLISH ABSTRACT: Water is life. Its availability and quality directly relates to what is possible in agriculture as well as human health. In Southern Africa, water issues have become an important political agenda as a result of the droughts that the region has been experiencing. The Southern Africa Development Community (SADC), in its water protocol advises its member states to set up river basin organisations to manage transboundary rivers in Southern Africa. The aim is to encourage the sustainable use of international rivers. Sharing international rivers has proven to be a very difficult issue as shown by the voting patterns on the UN Convention on the Law of Non Navigational Uses of Transboundary Rivers and the subsequent failure of entry into force of this convention. While strategic interests on the global levels manifest themselves in voting patterns in forums like the UN Assembly, the situation is trickier at the regional level. These strategic interests are ever present as a result of states’ need for recognition of their sovereignty and the inability of states to accept any hierarchical enforcement. This study investigates the impact of these interests at the basin level on the structure of cooperation. With the use of a case study, namely the Okavango River Basin Commission, and guided by regime theory, the study looks at the process of regime formation and maintenance in the basin. It concludes that states use cooperative arrangements (international water cooperation regimes) as tools for the strategic protection of their sovereignty.
AFRIKAANSE OPSOMMING: Water is lewe. Die beskikbaarheid en kwaliteit het direk te betrekking op wat moontlik toeneemed is in landbou so wel as menslike gesondheid. Water as ʼn noodsaaklike bron in suider-Afrika word meer en meer beskou as ʼn belangrike kwessie op die politieke agenda as gevolg van droogte wat in die streek ondervind word. ʼn Hoë vlak van belangrikheid word aan die bestuur van water binne die streek geheg. Die SAOG (Die Suider – Afrikaanse Ontwikkelings gemeenskap), het in sy water protokol aan sy lid state beveel om rivier kom organisasies te stig om beheer uit te oefen oor riviere in Suider- Afrika wat oor grense heen vloei. Die doel is om lidstate aan te moedig om die volhoubare gebruik van internasionale riviere te bevorder . Die vedeling van internasionale riviere is ‘n komplekse kwessie soos wat VN stempatrone aandui ten opsigte van die Wet op die Verbod teen Navigasie op Oorgrensende Riviere en die daaropvolgende versuim van die inwerkingtreding van die Konvensie aandui. As gevolg van state se behoefte vir erkenning van hul soewereiniteit en hul strategiese belange bly die deel van rivierkomme ‘n moeilike internasionale probleem. Hierdie studie ondersoek die impak van die bogenoemde belange op die kom vlak op die struktuur van samewerking. Met die gebruik van ʼn gevallestudie, naamlik die Okovango Rivier Kom Kommissie, en aan die hand van regime teorie, ondersoek die studie die proses van regime formasie asook die problematiek rondom die instandhouding van die Komissie. Die gevolgtrekking is dat state koöperatiewe reëlings (internasionale water samewerking regimes) as instrumente vir die beskerming van hul strategiese soewereiniteit en eie belange gebruik.
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Kotze, Christen Robynne. "Social organisation and population demographics of lions (Panthera leo) in the Okavango Delta." Thesis, 2016. http://hdl.handle.net/10539/21705.
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thesis submitted to the School of Animal, Plant and Environmental Sciences, Faculty of Science, University of the Witwatersrand, Johannesburg in fulfillment of the requirements for the degree of Masters in Science. Johannesburg 2016.The Okavango Delta in northern Botswana contains the largest, unfenced lion population in southern Africa, and is one of the most important population strongholds for the species on the continent. Despite its conservation importance, however, little information has been published on the drivers of lion ecology in this unique wetland ecosystem. In the Okavango Delta, the annual flood pulse causes dramatic seasonal contractions of available dry land, and consequently variable distribution and abundance of prey. Lions must therefore adapt to a dynamic environment not only on an annual basis, but also on a longer time-scale as inundation patterns cycle from periods of low to high floods. The main aim of the study was to determine which social and ecological factors were most important in determining lion population demographics and social organisation in the unique wetland environment of the Okavango Delta. Data were intensively collected on demographic rates and social organisation of five resident lion prides in the south-western Okavango Delta from 1997 to 2004, during which inundation patterns shifted from low to high floods. We investigated the effects of two ecological factors, namely prey availability and flood extent, and one social factor, namely intra-specific competition, on lion social organisation and population demographics. Lions occurred at high densities, and the population was regulated socially and not by resource limitation. Our results indicated that competition with neighbours exerted the most extensive influence on the lion population and significantly affected the survival of young cubs and reproductive rates. Competition reduced pride size, but contrary to our expectations, also negatively influenced sub-group size, indicating that territorial disputes do not drive sub-group patterns in the Okavango Delta. Prey availability did not appear to be an important limiting factor for the population, and group sizes were inversely related to prey availability, most likely due to habitat saturation resulting in higher levels of recruitment. Prey availability only influenced survival of young cubs, which are most vulnerable to nutritional stress. Higher levels of flooding led to smaller pride and sub-group sizes, indicating that higher flood levels for extended periods may lead to a decline in lion densities due to increased competition for available dry land. While flooding exerted no direct effect on demographic rates, we posit that habitat conversion during high flood cycles causes a decline in prey, resulting in a time-lagged effect on the lion population. Our results show that during low flood cycles when herbivore abundance is high, lions occur at high densities and are largely self-regulated. However, as flood levels increase, prey availability declines and lions are placed under increasing pressure for space and resources, which could ultimately lead to population decline. From a conservation perspective, the south-western Okavango Delta population is thus most vulnerable during periods of high floods, when lion densities naturally decline, and lions may be pushed towards the veterinary fence where human-lion conflict is high. Future studies should focus on how anthropogenic threats around the Okavango Delta threaten the viability of the lion population in this conservation area, and seek to secure important corridors to neighbouring populations. Keywords: lion, Panthera leo, social organisation, pride size, population demographics, survival reproduction, Okavango Delta, flooding, competition, prey abundance
LG2017
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"The impact of tourism on agriculture in the Okavango Delta, Botswana." Thesis, 2003. http://hdl.handle.net/10413/3957.
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In recent years the use of tourism as a development strategy by third world governments has increased, resulting in the intersection of international tourism and local agricultural strategies. The aim of this thesis is to critically assess the impact of tourism development on local agriculture in the Okavango Delta in Botswana. More specifically, the study appraises the current state of tourism and agriculture in the Okavango Delta, assesses the social, economic and environmental effects of tourism development on the Okavango Delta and its communities, examines local agricultural production and consumption patterns, assesses the patterns of supply and demand of food in the region, and evaluates the impact of tourism on local subsistence agriculture, while making use of both qualitative and quantitative data sources. The Okavango Delta region is faced with several socio-economic problems. These include high unemployment levels, unequal regional development, income inequalities and extreme levels of poverty. 'Rural-urban' migration by local subsistence farmers in search of formal employment opportunities has risen steadily since the early 1990s, resulting in unprecedented social changes to the inhabitants of the Delta, and the abandonment of traditional farming practices. This, together with the limited interaction between the local population and tourism industry, is increasingly leading to tension between local and foreign parties in the region. The large proportion of foreign owned tourist facilities and foreign investment results in major economic leakages, and the exclusion of Motswana from any form of meaningful participation in the tourism industry. The presence of foreign tourists in the Delta enforces the need for imports, increasingly damaging local agricultural production as both production and consumption becomes imported. If tourism is to be of any benefit to the local population in the Okavango Delta, there has to be local involvement and ownership. The fostering of linkages between tourism and other sectors, particularly agriculture, is imperative in attempting to bring about socio-economic growth in this region.Thesis (M.A.)-University of Natal, Pietermaritzburg, 2003.
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Neuenschwander, Amy Lynn 1968. "Remote sensing of vegetation dynamics in response to flooding and fire in the Okavango Delta, Botswana." Thesis, 2007. http://hdl.handle.net/2152/3646.
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The Okavango Delta, an internationally recognized wetland, is undergoing natural and anthropogenic change at a variety of spatio-temporal scales. The objective of this research was to utilize remotely sensed imagery to assess the spatio-temporal distribution of flooding and fire and their subsequent influences on vegetation as represented by vegetation index trajectories in the Okavango Delta. The characterization of the spatiotemporal dynamics of vegetation spectral response via a time-series of remotely sensed data not only informs ecosystem and disturbance theory but also presents new methodological applications for multi-temporal change analysis. Disentangling these components from a signal is critical for better assessing the interrelationships among climatic oscillations, disturbance regimes, and human management on ecosystem response. This research tested six hypotheses regarding flooding and fire, and found that the largest number of fires occurred either within 5 km of the border to the Wildlife Management Areas or within the active (flooded a minimum of every two years) floodplains. These hypotheses indicate that burning is highest where people have accessinto the management areas and where the natural resources are plentiful. Periodicities from vegetation signal time-series did not confirm published climate-driven periodicities of 3, 8, and 18-years but did reveal seasonal (6 month) and quasi-decadal periodicities. Vegetation trajectories were more predictable with increasing flood frequency and duration, but were less predictable with increased fire frequency. The fact that increased burning resulted in less predictable behavior indicates the potential of quantifying the anthropogenic influence on the landscape using remotely sensed imagery. Flooding and fire were not statistically correlated to the residual dynamics, refuting the conceptualization of flooding and fire as disturbance and supporting the interpretation of flooding and fire as disturbance regimes. This research thus contributes methodologically and theoretically to the ecology literature by operationalizing tests for disturbance versus disturbance regimes via spatio-temporal characterization. Further, this work extends change detection techniques typically implemented with coarser spatial resolution but more frequently acquired imagery by using harmonic regression and wavelet analysis with Landsat data. Lastly, this work provides a temporally rich assessment of recent vegetation, flooding, and fire trends for improving management efforts of the Okavango Delta.
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Harrison, Phillipa Anne. "The role of tourism in natural resource management in the Okavango Delta, Botswana." 2006. http://hdl.handle.net/10413/3427.
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In recent years the use of tourism as a development strategy by Third World governments has increased, resulting in the intersection of international tourism and local resource utilisation patterns. The aim of this thesis is to critically assess the impact of tourism in the utilisation and management of natural resources in the Okavango Delta in Botswana. More specifically, the study appraises the current state of tourism and natural resource utilisation and management in the Okavango Delta; assesses the past and present forms of resource utilisation practised by the local inhabitants scattered throughout the Delta area; focuses on the implementation of government policy regarding resource use; highlights past and present relationships between tourism and resource utilisation; and examines the impact of tourism on the areas resources, environment and local inhabitants. Research has shown that the Okavango Delta, which is Botswana's primary tourism area, is faced with a number of social, economic and environmental challenges. These include extreme levels of poverty, especially in the rural areas; lack of infrastructure; competition over land and resources; growing regional inequality; social degradation; increased imports leading to foreign exchange leakages; changes in subsistence strategies and increased 'rural-urban' .migration; and the loss of control of the region by the local population to the global tourism system. The Okavango Delta is in the process of undergoing a change from traditional, rural, subsistence economies and livelihoods to capitalist, commercial-driven economic structures. In the Okavango Delta, as in many places around the world, people are in the process of being integrated into national level political, social and economic institutions, both within and outside of their control. The creation of employment for the local population, the sustainable use of the Delta and its resources, the development of the local agricultural industry, the continued growth of the tourism industry, and striking a balance between the conservation/preservation of the Okavango and meeting the water requirement needs of Angola, Namibia, and Botswana's growing populations are amongst the key concerns present in the area. 11 Tourism in the Okavango Delta is directly dependent upon the utilisation of the region's natural resources of wildlife, water and natural vegetation areas for the industry. As such, tourism has increasingly impacted upon the way, and degree to which, these resources are managed and utilised, hence being identified as a key factor effecting the resource sector. If the Government of Botswana is to develop a tourism industry which fosters environmental and natural resource preservation, rather than maintaining a heavy dependence on limited and fragile resources, a better understanding of the relationship between the two sectors is necessary. Enhancing the positive linkages between tourism and natural resource utilisation in the Okavango Delta region represents an important means to stimulate increased natural resource and environmental protection, and improve the distribution of tourism benefits to rural communities. amongst the key concerns present in the area. Tourism in the Okavango Delta is directly dependent upon the utilisation of the region's natural resources of wildlife, water and natural vegetation areas for the industry. As such, tourism has increasingly impacted upon the way, and degree to which, these resources are managed and utilised, hence being identified as a key factor effecting the resource sector. If the Government of Botswana is to develop a tourism industry which fosters environmental and natural resource preservation, rather than maintaining a heavy dependence on limited and fragile resources, a better understanding of the relationship between the two sectors is necessary. Enhancing the positive linkages between tourism and natural resource utilisation in the Okavango Delta region represents an important means to stimulate increased natural resource and environmental protection, and improve the distribution of tourism benefits to rural communities.Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2006
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Mbaiwa, Joseph Elizeri. "Tourism development, rural livelihoods, and conservation in the Okavango Delta, Botswana." 2008. http://hdl.handle.net/1969.1/ETD-TAMU-3064.
Full textAbstract:
This study analyzed changes in livelihoods before and after tourism development
at Khwai, Mababe and Sankoyo villages in the Okavango Delta. Specifically, it analyzed
how people interacted with species like giraffe (Giraffa camelopardalis), sable antelope
(Hippotragus niger) and thatching grass (Cymbopogon excavatus) before and after
tourism development. This analysis was expected to measure the effectiveness of
tourism development as a tool to improve livelihoods and conservation. The concept of
social capital, sustainable livelihoods framework and the Community- Based Natural
Resource Management (CBNRM) paradigm informed the study. Qualitative and
quantitative data were gathered through field-based research, using tools of participant
observation, semi-structured interviews, and key informant interviews. Results indicate
that local customs and institutions at Khwai, Mababe and Sankoyo ensured the
conservation of resources in pre-colonial Botswana. However, British colonial rule
(1885-1966) affected traditional institutions of resource use hence the beginning of
resource decline. The British colonial rule and the first 15-20 years after Botswana’s independence from British rule saw an increase in resource degradation. Results also
indicate that since CBNRM began in the 1990s, tourism development has positive and
negative effects on rural livelihoods. On the positive side, tourism development in some
ways is achieving its goals of improved livelihoods and conservation. Residents’
attitudes towards tourism development and conservation have also become positive
compared to a decade ago when these communities were not involved in tourism
development. On the negative side, tourism is emerging as the single livelihood option
causing either a decline or abandonment of traditional options like hunting and gathering
and agricultural production. Reliance on tourism alone as a livelihood option is risky in
the event of a global social, economic and political instability especially in countries
where most tourists that visit the Okavango originate or in Botswana itself. There is
need, therefore, for communities to diversify into domestic tourism and small-scale
enterprises. On the overall, tourism development through CBNRM indicates that it is a
viable tool to achieve improved livelihoods and conservation in the Okavango Delta.
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Laletsang, Kebabonye. "Groundwater investigations using geophysical techniques at Marophe, the Okavango Delta, Botswana /." 1995. http://collections.mun.ca/u?/theses,30649.
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Boyes, Rutledge Stephen. "The ecology of Meyer's parrot (Poicephalus meyeri) in the Okavango Delta, Botswana." Thesis, 2008. http://hdl.handle.net/10413/10836.
Full textAbstract:
Meyer’s Parrot Poicephalus meyeri is the smallest of the nine Poicephalus
parrots, forming the P. meyeri superspecies complex with five congeners. Their distributional
range far exceeds any other African parrot, extending throughout subtropical Africa. Meyer’s
Parrots had previously not been studied in the wild, and therefore, gathering high-quality
empirical data on their behavioural ecology became a research and conservation priority. The
primary aim of the study was to correlate environmental (e.g. rainfall, habitat availability,
resource characteristics, food resource abundance and temperature) and social (e.g. inter- and
intra-specific competition, predation, and human disturbance) variables with aspects of their
ecology (e.g. flight activity, food item preferences, breeding activity, and group dynamics) to
evaluate the degree of specialization in resource use (e.g. trophic, nesting and habitat niche
metrics).
African deforestation rates are the highest in the world, resulting in twelve out of the
eighteen Meyer’s Parrot range states undergoing drastic loss of forest cover over the last 25
years. Most commentary on the population status of Meyer’s Parrots and other Poicephalus
parrots pre-dates this period of rapid deforestation In addition, over 75 000 wild-caught
Meyer’s Parrots and almost 1 million wild-caught Poicephalus parrots have been recorded in
international trade since 1975. Empirical data from this study was used to identify ecological
weaknesses (e.g. niche specialization or low breeding turnover) for evaluation within the
context of deforestation in the African subtropics. Baseline data on the breeding biology and
nest cavity requirements of Meyer’s Parrots was also necessary to assess the viability of
applying the conservative sustained-harvest model to African parrots. A unifying goal of this
study was to advance our knowledge of the ecology of African parrots and other
Psittaciformes by assessing the validity of current hypotheses put forward in the literature.
The Meyer’s Parrot Project was initiated in January 2004 on Vundumtiki Island in the
north-eastern part of the Okavango Delta, Botswana. Due to high flood waters between
March and July 2004, road transects were postponed till August 2004. Transects were
conducted at Vundumtiki from August 2004 to July 2005 and February 2007 to August 2007,
and at Mombo from August 2005 to January 2006. During 480 road transects over 24
months, food item preferences closely tracked fruiting and flowering phenology, resulting in
significant positive correlations between Levins’ niche breadth, rainfall and food resource
availability. Meyer’s Parrot can, therefore, be considered opportunistic generalists predispersal
seed predator that tracks resource availability across a wide suite of potential food
items, including 71 different food items from 37 tree species in 16 families. Meyer’s Parrots
were, however, found to be habitat specialists preferring established galleries of riverine forest
and associated Acacia-Combretum marginal woodland. These strong habitat associations
facilitate their wide distribution throughout the Kavango Basin, Linyanti Swamps, down the Zambezi valley, up along the Rift Valley system in associations with the great lakes, through
the Upper Nile and the Sudd, and west as far as Lake Chad through the Sahel.
Seventy-five nest cavities were measured during this study, including 28 nest cavities
utilized by Meyer’s Parrots within the 430ha sample area at Vundumtiki. Over 1700 hours of
intensive nest observations at six nest cavities was undertaken. Meyer’s Parrots formed
socially monogamous pair-bonds maintained over at least four breeding seasons. Breeding
pairs established breeding territories up to an estimated 160ha within which there were 1–6
nest cavities. Eggs hatched asynchronously, yet nestlings fledged synchronously with similar
body size and condition. There was evidence to support the incidence of extra-pair
copulations, however, mitochondrial DNA sequence data are required to confirm the
incidence of extra-pair fertilizations. Meyer’s Parrots had no preferences in regard to nest tree
species beyond the incidence of suitable nest cavities, which are selected and further
excavated to accommodate their non-random nest cavity preferences. There was a significant
non-nesting Meyer’s Parrot population during the breeding season, likely due to this longlived
cavity-nester delaying nesting until a suitable breeding territory becomes available.
Meyer’s Parrots utilize communal roosts during summer and disperse from them
according to the Foraging Dispersal Hypothesis. Due to the requirement to roost during the
middle of the day to avoid heat stress, Meyer’s Parrots have bimodal flight and feeding
activity patterns. The highest probability of locating Meyer’s Parrots is between 08h30 and
11h00 during summer when both adults are feeding on the seeds of fleshy-fruits in riverine
forest communities.
Due to the paucity of data on the current distribution and population status of Meyer’s
Parrots and other African parrots, a continent-wide survey of all African parrots represents a
conservation priority. Current deforestation rates in several Meyer’s Parrot range, their
specialist habitat associations, and lack of evidence to support adaptability to a changing
landscape mosaic necessitate the re-classification of Meyer’s Parrots as data deficient or nearthreatened.
Based on low breeding population due to limited breeding opportunities, the
CITES Appendix II wild-caught bird trade should also be halted until the sustainability of this
trade has been evaluated and the relevant information made available.Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.
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Heinl, Michael [Verfasser]. "Fire regime and vegetation response in the Okavango Delta, Botswana / Michael Heinl." 2005. http://d-nb.info/97811728X/34.
Full text
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Tedder, Michelle Jennifer. "Dry woodland and savanna vegetation dynamics in the Eastern Okavango Delta, Botswana." Thesis, 2012. http://hdl.handle.net/10413/10005.
Full textAbstract:
The Okavango Delta is an extremely dynamic system with variable vegetation comprised of permanent
swamps, seasonal swamps, dry islands, floodplains and dry grassland, savanna and woodland. The system
is largely driven by the interaction between fire and the annual flood, which filters down from the
Okavango River catchments in Angola. While extensive research has been conducted on the flood-driven
vegetation little is known about the dry woodland and savanna regions bordering these flood-driven
habitats. A taxonomic classification of woody species composition resulted in eleven vegetation types.
These data were then reanalyzed in terms of woody species morphology allowing these eleven vegetation
types to be grouped into four functional response groups in order to provide a platform for improving the
understanding of how dry woodland and savannas interact with the environment. These four groups were
the savanna group mixed thornveld and the three woodland groups; mixed broadleaf woodland, shrub
mopane woodland and tall mopane woodland. Burning in mixed thornveld and mixed broadleaf woodland
was found to decrease woody species density and grass fuel loads and could be used for grazing
management to remove unpalatable growth and improve grass species composition, while burning in
shrub mopane woodland and mixed mopane woodland merely decreased the woody understory and is not
recommended. Utilization dominated by grazing livestock resulted in overutilization of the grass sward
leading to bush encroachment in both mixed thornveld and shrub mopane woodland, while utilization by
goats alone resulted in underutilization of the grass sward and a dominance of herbaceous annuals.
Livestock utilization had no effect on the occurrence of Pecheul-loeschea leubnitziae, a shrubby pioneer
previously thought to be an indicator of overgrazing, however extensive P. leubnitziae cover was
associated with a sward dominated by shade-tolerant grasses with low forage quality. Shrub mopane
woodland and tall mopane woodland appear to be more stable vegetation states than mixed broadleaf
woodland and mixed thornveld being less vulnerable to colonization by pioneer species and alteration as a
result of utilization or environmental factors. For this reason management and monitoring of mixed
thornveld and mixed broadleaf woodland is essential to prevent vegetation degradation and to ensure
optimal forage availability for both livestock and wildlife.Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.
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Chase, Michael John. "International river basin management : a case study of the Okavango River Basin." 2002. http://hdl.handle.net/10413/4507.
Full textAbstract:
This dissertation reviews the principles of International River Basin Management and their
application by the governments of Angola, Botswana and Namibia. The dissertation deals with the
issues popularised by governments, water planners and international agencies that the twenty-first
century's conflicts will be fought over water. Increasingly this concern is being used to justify new
water-supply dams and river diversion projects. This is especially so in arid Southern Africa, the
focus of this dissertation, where numerous major international water transfers are underway and
many more are being planned. While Namibia's growing thirst is a serious problem, the story is more
complicated than just too many basin states putting their straws into one glass. The growing conflicts
over the Okavango's water use raise broader questions about ownership of common resources, and
equity of access to those resources.
Most southern African countries depend on primary natural resources to sustain economies and their
people. The environmental issues are remarkably similar in countries within the region, and the
economic, social and political fortunes of the individual countries are intertwined. Furthermore, the
ways in which resources are being managed are similar and thus cause for common concern. In
general, the ability of countries in the region to achieve sustainable development depends not on
national policies but also on the commitment of neighbours to practice sound environmental
management. This is because activities in one country can easily cause impacts on a neighbour and
possibly result in "downstream" opportunity costs.
This case study of the Okavango River Basin, a river facing prospective developments from riparian
states Angola, Botswana and Namibia, attempts to find sustainable solutions to solving international
resource conflict. In addition to outlining the possible future threats to the Okavango River, this
study proclaims a number of recommendations in the way of declaring alternatives to Namibia's
plans to extract water from the Okavango River. One such recommendation is the encouragement of
Water Demand Management as an alternative to water transfer by Namibia. This management
strategy is aimed at optimising the use of available water rather than developing new or extended
supplies and as a result it has a vital role to play since it contributes to sustainable development rather than over exploitation of limited natural resources. The majority of large rivers in the Southern African Development Community (SADC) are shared by
three or more countries, and as the region's water resources come under growing development
pressure, the importance of establishing effective national and regional methods and institutions for
sustainably managing these resources will increase greatly. From economic, ecological and human
welfare perspectives, the Okav,ango River Basin is arguably one of the most important transboundary
natural resources (TBNR) in the region. Owing to the basin's remoteness and history of conflict, the
Okavango was spared much of the destructive developments that rivers in the region have suffered.
As a result, the relatively pristine Okavango ecosystem continues to provide significant benefits to
the region much as it has done for centuries. As we approach the new millennium, however, it is
clear that the health of the Okavango River Basin is threatened as riparian states increasingly turn to
the Okavango to support their growing populations and economies.Thesis (M.Env.Dev.)-University of Natal, Pietermaritzburg, 2002.
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Mokae, Motsidisi Lorraine Lolo. "Histomorphology as a tool to assess the health status of five economically important fish species in the Okavango Delta Panhandle, Botswana." Thesis, 2014. http://hdl.handle.net/10210/8811.
Full textAbstract:
Ph.D. (Zoology)Histomorphology as a tool to assess the health status of five economically important fish species in the Okavango Delta Panhandle, Botswana the Okavango Delta, and an inland freshwater wetland of national and international importance was designated by the Ramsar Convention in 1996. This site is of global importance because of a wide diversity of fish species found in this freshwater ecosystem. The Okavango Delta is also one of the last 'near pristine' sites on the African continent and therefore serves as an ideal reference site to describe the normal histomorphology of selected organs in sentinel fish species which could be used as reference for future toxicological studies. The aim of this study was to assess the health status of five economically important fish species namely, Clarias gariepinus (Burchell, 1822), Clarias ngamensis (Castelnau, 1861), Serranochromis robustus jallae (Gunther, 1864), Serranochromis angusticeps (Boulenger, 1907) and Hydrocynus vittatus (Castelnau, 1861) sampled from the Okavango Delta Panhandle, by describing the normal histomorphology of the liver, gills and gonads of the sentinel species. The sentinel fish species are of significant importance because they form an integral part of the small-scale commercial, subsistence and recreational fisheries in this ecosystem. In the past few decades, fish-health research has focused almost exclusively on histopathological alterations resulting from pollution caused by exposure to chemicals, parasitesand pathogens. Limited attention has been devoted to the normal histomorphology and health status of fish species in various aquatic ecosystems including the Okavango Delta Panhandle. Also, histopathological evaluations noted only the presence of abnormalities without quantitative assessment of the extent of the abnormalities within each tissue section. The absence of baseline normal histomorphology and numerical data however, makes it difficult to establish cause-and-affect relationships between pathology and contamination patterns in various fish species. It is imperative therefore, that the normal histomorphology of organs in fish species occurring in this region should be known so that histopathological conditions maybe accurately diagnosed…
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"Community-based natural resource management, livelihood diversification & poverty alleviation : a case study of NG 22/23 and associated communities, Okavango Delta, northern Botswana." 2006. http://hdl.handle.net/10413/3453.
Full textAbstract:
This paper presents a case study from Ngamiland, northern Botswana where community~
based natural resource management (CBNRM), through a joint venture agreement (NA)
between a Community~based Organisation (CBO) and the private sector for nonconsumptive
tourism has been implemented with the objective of contributing to localised
poverty alleviation and livelihood diversification through employment and CBO fee
revenue. The economic contribution of these benefits is considered with respect to
commonly accepted norms and standards within the development ideology of sustainable
development and its global measurements; therefore, a brief background of the concepts
of poverty, livelihood and ecotourism is presented to provide context for the evaluation of
CBNRM as a preferred land~use in Botswana. An evaluation of the significance of wage
employment revenue and consequent remittances in the specific case study is intended to
contribute to existing studies which have primarily emphasised the contribution of CBO
fee revenue only to households. It is concluded that wage employment revenue makes a
significant contribution at a household level to localised poverty alleviation and
livelihood diversification compared to the insignificant contribution ofCBO fee revenue.Thesis (M.Env.Dev.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.