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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

A Geographical Information System for Fire Management by the Western Cape Nature Conservation Board

Ford, Francois York 04 1900 (has links)
Thesis (MSc (Geography and Environmental Studies))--University of Stellenbosch, 2006. / A multitude of unique fauna and flora exist within the Western Cape of South Africa. Fire plays an intricate role in the conservation and extinction of many of these species. It is therefore imperative to understand this delicate relationship in order to help preserve the province’s uniquely balanced ecosystem. The Western Cape Nature Conservation Board (WCNCB) expressed the need for a system that would allow reserve managers to produce basic fire frequency and veld age maps with considerable ease. These maps are needed for intelligent decisionmaking regarding the management of veldfires. Information concerning vegetation and historical veldfires in the Western Cape, collected over a period of 50 years exist in tabular format in databases of the WCNCB. Some of these tables contain spatial information elements, such as areas affected by fires. Tabular data with spatial elements can be converted to a geographical information system (GIS) format, extracting value previously shielded from the user. Using GIS techniques and the programming language Avenue, two tools with powerful decision-making qualities were created to extract value from these datasets. One tool shows the fire history of a specified area as a digital map. This map shows areas with varying occurrences of fires over time, thereby highlighting hot spots within the specified location. The ability to view various fire scar datasets spatially over a specified period, as opposed to records in a table, enables the user to understand the extent to which areas have been repeatedly exposed to fire and quickly identify areas most affected. The second tool shows vegetation age in a similar fashion, allowing the user to see the current spatial distribution of vegetation and its age. Knowledge about the age of indigenous vegetation, such as fynbos, in a predetermined area, facilitates the reserve manager in decisions related to block burning. This is an accepted practise in areas where vegetation requires fire to stimulate germination. Both tools provide decisionmaking support to reserve managers regarding the most suitable course of action in terms of the implementation of a proactive or passive approach towards fires. This study satisfies the needs of the WCNCB by exploring the hidden value within their datasets. GIS supported by the programming language, Avenue, was successfully utilised in the development of a system capable of extracting information from current datasets to support reserve managers in their critical decision-making processes.
82

Reconstruction of a fire regime using MODIS burned area data : Charara Safari Area, Zimbabwe

Magadzire, Nyasha 03 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Current efforts to address Zimbabwe‘s decade long veld fire crisis has partly been hindered by a lack of financial resources and fire data. This study illustrates the potential of using the MODIS burned area product as an alternative cost- and time-effective method for reconstructing historical fire records in Zimbabwe. Two MODIS burned area products were evaluated, namely the MCD45A1 and WAMIS (Meraka Institute‘s MODIS burned area product). Both products yielded similar levels of accuracy despite the difference in algorithms. However, it is assumed that at certain thresholds, either in tree cover or fire intensity, WAMIS ceases to map fires as accurately as the MCD45A1. Ten years of fire data for Charara Safari Area (CSA) was extracted from the MCD45A1, and used as a basis to establish six parameters: fire incidence, extent, seasonality, fire size, frequency and fire return interval (FRI). It was observed that approximately 50% of CSA burned annually, with an average of 132 fires occurring every year. Although there was no overall increase or decrease in the extent of area burned over the 10 year study period, an increasing trend in fire incidence was noted. Through an assessment of effective fire size, it was established that more fires in CSA were gradually becoming smaller in size, while the extent of area burned remained fairly constant. Hence, the increase in fire incidences and lack of a corresponding increase in area burned. This study was also used to identify areas in the fire regime that may be a potential ecological risk to the miombo woodland in CSA. Three points of concern were revealed: firstly, a high prevalence of late season fires was observed in the northern bounds of CSA. Secondly, 64.2% of the total area burned in CSA burned between 6 and 10 times over the 10 year period, and lastly, 85% of the total area burned over the period 2001 and 2010 had a FRI of less than 2 years. The combination of late season fires, high fire frequency and short FRI in CSA is indicative of possible alterations in the state of the miombo woodlands, which may have negative socio-economic implications on CSA and its surrounding communities. This study has demonstrated that the MCD45A1 is a useful source of much needed fire information for Zimbabwe. Therefore, the possibility of integrating methods employed in this study into the current collection of fire data should be given due consideration. / AFRIKAANSE OPSOMMING: Huidige pogings om Zimbabwe se dekade lank veldbrand krisis aan te spreek is gedeeltelik belemmer deur 'n gebrek aan finansiële hulpbronne en vuurdata. Hierdie studie illustreer die potensiaal van die gebruik van die MODIS verbrande area produk as 'n alternatiewe koste-en tyd-effektiewe metode vir die rekonstruksie van historiese vuurrekords in Zimbabwe. Twee MODIS verbrande area produkte is geëvalueer, naamlik die MCD45A1 en WAMIS (Meraka Instituut se MODIS verbrand area produk). Beide produkte het soortgelyke vlakke van akkuraatheid opgelewer ten spyte van die verskil in die algoritmes. Dit word egter aanvaar dat op sekere drempels, óf in die boom bedekking, of brandintensiteit, WAMIS brande minder akkuraat karteer as die MCD45A1 produk. Tien jaar van vuurdata vir Charara Safari Area (CSA) is uit die MCD45A1 data onttrek, en gebruik as 'n basis om ses parameters vas te stel: vuurvoorkoms, omvang, seisoenaliteit, vuurgrootte, frekwensie en tyd tussen die terugkeer van vuur na ‗n spesifieke plek (nl. FRI). Dit is waargeneem dat ongeveer 50% van die CSA jaarliks gebrand word, met 'n gemiddeld van 132 brande wat elke jaar voorkom. Daar was nie 'n algehele toename of afname in die omvang van die totale verbrande area oor die 10 jaar studietydperk nie. Maar 'n toenemende neiging in die vuurvoorkoms was wel opgemerk. Deur middel van 'n assessering van effektiewe vuurgrootte, is daar vasgestel dat meer kleiner brande in CSA voorkom, terwyl die omvang van die verbrand area redelik konstant gebly het. Dus was daar ‗n toename in die aantal vuurvoorvalle al was daar nie 'n ooreenstemmende toename in die totale verbrande oppervlakte was nie. Hierdie studie is ook gebruik om gebiede in die vuurregime te identifiseer wat 'n potensiële ekologiese risiko vir die miombobosveld in CSA inhou. Drie punte van kommer word geopenbaar: eerstens, 'n hoë voorkoms van laatseisoen brande is waargeneem in die noordelike grense van CSA. Tweedens, 64,2% van die totale verbrande oppervlakte in die CSA brand tussen 6 en 10 keer bine die 10-jaar periode. Laastens, 85% van die totale verbrande oppervlakte oor die tydperk 2001 tot 2010 het 'n FRI van minder as twee jaar. Die kombinasie van laatseisoen brande, hoë vuurfrekwensie en kort FRI in CSA is 'n aanduiding van moontlike veranderinge in die toestand van die miomboveld, wat negatiewe sosio-ekonomiese implikasies op die CSA en die omliggende gemeenskappe kan uitoefen. Hierdie studie het getoon dat die MCD45A1 'n nuttige bron van broodnodige vuur inligting vir Zimbabwe is. Daarom, moet die moontlikheid van die integrasie van die metodes wat gebruik word in hierdie studie in die huidige versameling van vuurdata behoorlike oorweging gegee word.
83

Discursive Horizons of Human Identity and Wilderness in Postmodern Environmental Ethics: A Case Study of the Guadalupe Mountains of Texas

Hood, Robert L. (Robert Leroy) 05 1900 (has links)
Using a genealogy of the narratives of the Guadalupes, I explore three moral identities. The Mescalero Apache exist as caretakers of sacred space. Spanish and Anglo settlers exist as conquerors of a hostile land. The park service exists as captives, imprisoned in the belief that economic justifications can protect the intrinsic value of wilderness. The narrative shift from oral to abstract text-based culture entails a shift from intrinsic to instrumental valuation. I conclude that interpretation of narratives, such as those of the Guadalupes, is not by itself a sufficient condition for change. Interpretation is, however, a necessary condition for expanding the cultural conversation beyond merely instrumental justifications to include caring for wilderness's intrinsic values.
84

In Defense of Wilderness: A Documentation of the Social and Cultural Aspects of the Boundary Waters Canoe Area (BWCA)

Brickle, Tyler A. 05 1900 (has links)
My thesis research provides an alternative argument for the protection of the wilderness that extends far beyond that of the purely biological and instead looks at wilderness for the intrinsic value, focusing on the social and cultural aspects. Through an ethnographic approach, I uncovered the how, why, and in what context people connect with wilderness and how people lean on these experiences. Through analysis of the interviews and data that was collected, I was able to identify tangible and intangible values associated with wilderness exploration and understand how these social and cultural aspects manifest themselves in people's day-to-day lives.
85

The politics of John Muir

Freeman, Dorothy M. 01 January 1977 (has links) (PDF)
A man does not always see himself as others see him. John Muir is venerated by several generations of Americans as a man who left a legacy of State and National Parks, State and National Forests, outdoor beauty and untouched wilderness areas which would never have survived has it not been for this dedicated man. He did not plan such a course. He did what he found necessary to be done, without thought of personal gain or public honor. However, during his lifetime there were those who did not view him with such veneration. Countless ranchers, lumberman and politicians must have considered him a formidable foe. The purpose of this paper is to show how involved he was politically. He really became quite an adept politician, although the whole idea would have been extremely distasteful to him if he had heard himself designated as such.
86

The implementation of an environmental monitoring and management system in the wilderness area of the Hluhluwe-Imfolozi Park.

Cryer, Paul Bernard. January 2009 (has links)
KwaZulu-Natal’s Hluhluwe-Imfolozi Park has historically been prioritized for biodiversity conservation but it also has the oldest protected wilderness area in the country. For 50 years, conservation management, tourism and education within the Imfolozi Wilderness Area have generally been carried out using non-mechanized wilderness principles. The validity of the Imfolozi Wilderness is constantly questioned in terms of efficiency, equity and aesthetics and is consequently subject to a variety of pressures that those different ideologies can exert. The historical development and applicability of the wilderness concept is examined here against evolving South African social and environmental circumstances. Whilst this investigation confirms the findings that colonialism and apartheid resulted in the exclusion of local peoples from protected areas, it also takes note that Imfolozi’s history is characterized by organizations and individuals who ignored the racist laws of the time. Nevertheless, management structures pertaining to both politics and conservation tended to be top-down, such that the Imfolozi Wilderness retained an air of elitism, regardless of attempts to be racially inclusive. Modern trends in protected area management expose the necessity of refining the justification of wilderness areas, to simultaneously recognize localized priorities and the importance of such areas to the planet’s ecological wellbeing. Without attempting to resolve philosophical debates but, at the same time, recognizing their validity, protected area management requirements for the Imfolozi Wilderness are examined in terms of the legal mandate handed to the management agency. This leads to the selection of the Limits of Acceptable Change planning and management system which is implemented as an action research project in conjunction with the Imfolozi Management Team, over a three year period. This involved: defining legal mandates and area issues; defining the zonation categories for the wilderness area; selecting the indicators to measure human impact; compiling an inventory of conditions in the wilderness area; specifying standards; examining alternative zonation category allocations from stakeholders and selecting a preferred alternative. The desired outcome was the establishment of a system in which managers could receive ongoing collaboration from stakeholders and consultatively develop a defendable wilderness management strategy that would meet the legal requirements of the area’s proclamation. Through a descriptive narrative, this dissertation provides an account of the implementation process and discusses to what extent this has been achieved. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.
87

FIRE HISTORY OF THE GILA WILDERNESS, NEW MEXICO.

Swetnam, Thomas W., Swetnam, Thomas W. January 1983 (has links)
No description available.
88

The wilderness knot

Washington, Haydn G., January 2006 (has links)
Thesis submitted for the degree of Doctor of Philosophy University of Western Sydney. / Title from electronic document (viewed 2/6/10) Interviews held with: "James' Dharug, Traditional Custodian; Dr. Rob Lesslie, conservation biologist, Dr. Val Plumwood, environmental philosopher, Virginia Young, Director WildCountry Project, Professor Mike Archer, Dr. Deborah Bird Rose, anthropologist, Ms. Penny Figgis, former Vice President of ACF, Dr. Tim Flannery, Director South Australian Museum, Mr. Dean Stewart, Aboriginal Education Officer, Melbourne Botanic Gardens, Dr. Rosemary Hill, ACF Northern Lands Project Officer, Professor Harry Recher.
89

Mapping the potential of veld fire occurrence in the mountain regions of the South Western Cape, using GIS

Akinnusi, Olamigoke Adekunle 04 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: Veld fires in the mountain regions of the South Western Cape are an annual occurrence. These veld fires occur as a result of human, natural and unknown causes. The Mediteranean weather conditions of the South Western Cape and its typical vegetation are conducive to these fires. Within the mountain regions of the South Western Cape, the use of fire can be advantageous for conservation and forest managers as a tool for fire management e.g. preparation of fire belts, reduction of veld fire occurrence by burning fuel load, rejuvenation of indigenous vegetation and enhancing the water yield of surrounding areas within their management area. Abnormally high incidences and run away veld fires within the management area of conservation and forest managers leads to. the loss of biodiversity, destruction of properties and loss of human lives, and extensive soil erosion. This study aimed at identifying factors contributing towards the occurrence of veld fires in the mountain regions of the South Western Cape, and using GIS to analyse spatially the contributing variables, and to generate seasonal veld fire hazard maps. Potential veld fire occurrence on a seasonal basis was mapped using spatial analyses of variables that are significant to the distribution of veld fires within the study area. Variables used to assess potential veld fire occurrences were: vegetation, slope, population density (human influence), proximity to roads, mean monthly maximum temperatures and mean monthly rainfall. The veld fire hazard maps generated indicated that potential for veld fire occurrence is high in the summer and autumn months, decreasing to a low in the winter and spring seasons. The exception is the Southern Cape sub-region where the possibility of veld fires can be quite high in winter as a result of Fohn-like berg winds. These winds are characterized by sudden increases in temperature and decreases in humidity that may pose severe fire hazards. Reducing and containing veld fires in the mountain regions of the South Western Cape depends on the effective use of the seasonal veld fire hazard maps. The maps can be used to delineate critical zones of veld fire occurrence which can be used for evaluating costeffective control measures and can be implemented to reduce the level of veld fire danger within the management areas of conservation and forest managers. There is a need for a Catchment Management System (CMS) (Richardson, Van Wilgen, Le Maitre, Higgins & Forsyth, 1994) that can be used to generate daily probabilities of veld fire occurrence and to link these to fire-spread models for predicting or simulating expected fire directions and severities or intensities, and educating people about fires and the damage it can do. / AFRIKAANSE OPSOMMING: Elke jaar kom daar veldbrande in die berggebiede van die Suidwes-Kaap voor. Die oorsake van hierdie veldbrande is van menslike, natuurlike of onbekende oorsprong. Die Mediterreense weersomstandighede en die tipiese plantegroei van die Suidwes-Kaap is ook bevorderlik vir die ontstaan van veldbrande. In die berggebiede van hierdie streek kan die gebruik van vuur egter ook tot voordeel van natuurbewaring en bosbou aangewend word deurdat dit gebruik kan word as 'n metode om die brande te bestuur, soos in die voorbereiding van brandpaaie, in die vermindering van die voorkoms van veldbrande deur vooraf van die brandbare materiale af te brand, in die vernuwing van die inheemse plantegroei en in die verhoging van wateropbrengs in die omliggende gebiede binne die area wat bestuur moet word. 'n Abnormale hoë voorkoms van veldbrande binne die bestuursgebied van bewarings- en bosboubestuurders lei egter tot 'n verlies aan biodiversiteit, die vernietiging van eiendom, 'n verlies aan menselewens en uitgebreide gronderosie. Die doel van hierdie studie was om die faktore wat bydra tot die voorkoms van veldbrande in die berggebiede van die Suidwes-Kaap te identifiseer, om GIS te gebruik om 'n ruimtelike analise van die bydraende veranderlikes te doen en om dan 'n seisoenale veldbrandgevaarkaart saam te stel. Die potensiële voorkoms van veldbrande op 'n seisoenale basis is gekarteer deur gebruik te maak van ruimtelike analises van die veranderlikes van belang in die verspreiding van veldbrande in die studiegebied. Die volgende veranderlikes is gebruik om die potensiële voorkoms van veldbrande te bepaal: plantegroei, helling, bevolkingsdigtheid (invloed van mense), afstand vanaf paaie, gemiddelde maandelikse maksimum temperature en gemiddelde maandelikse reënval. Die veldbrandgevaarkaarte wat ontwikkel is, het aangetoon dat die potensiële voorkoms van veldbrande hoog is in die somer- en herfsmaande en dan afneem tot 'n laagtepunt in die winter en lente. 'n Uitsondering is die Suid-Kaap-substreek waar die moontlikheid van veldbrande selfs in die winter taamlik hoog is as gevolg van Fëhn-tipe bergwinde. Hierdie winde word gekenmerk deur In skielike toename in temperatuur en In afname in humiditeit wat die brandgevaar skerp kan verhoog. Die vermoë om veldbrande in die berggebiede van die Suidwes-Kaap te verminder en te beperk, sal grootliks afhang van die effektiewe gebruik van die seisoenale veldbrandgevaar-kaarte. Die kaarte kan gebruik word vir die afbakening van kritieke sones vir die voorkoms van veldbrande wat dan gebruik kan word vir die evaluering van koste-effektiewe beheermaatreëls. Hierdie kaarte kan dan geïmplementeer word om die vlakke van veldbrandgevaar binne die gebiede waarvoor bewarings- en bosboubestuurders verantwoordelik is, te verminder. Daar is In behoefte aan In opvanggebiedbestuurstelsel (OGB) (Richardson, Van Wilgen, Le Maitre, Higgins & Forsyth 1994) wat gebruik kan word om daaglikse waarskynlikhede vir die voorkoms van veldbrande te genereer. Dit kan gekoppel word aan brandverspreidingsmodelle wat die verwagte rigting van brandverspreiding, asook die ems of intensiteit daarvan, kan voorspelof simuleer. Die publiek moet ook ingelig word oor veldbrande en die skade wat daardeur aangerig kan word.
90

Environmental education and high school backpacking

Ficke, David Russell 01 January 2005 (has links)
The call of the wilderness resonates in all of our hearts, with the desire to get in touch with nature and experience wilderness at some level. This project gives the high school teacher the practical resources necessary to share the passion of being in the wilderness with high school students.

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