Typescript. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1990. / Includes bibliographical references (leaves 127-136) / Microfiche. / ix, 136 leaves, bound ill. 29 cm

The study sought to test the applicability of the Hotelling rule in South Africa. In environmental economics, the Hotelling rule has come to be a pillar of the exhaustible resources framework and in addition to this, it has presented essential insights into the consumption and extraction of non-renewable resources. Hotelling sought to address one important question which had been unanswered regarding the depletion of exhaustible resources: How much of the natural resource in question should be consumed presently and how much of it should be stocked up for future generations? The focus was to find a solution for those involved in the exploitation of natural resources to choose between the current value of the natural resource if extracted and sold and the future increased value of the asset if left unexploited. According to the Hotelling rule, the extraction path in competitive market economies will, under certain circumstances, be socially optimal. An extraction path that is not socially optimal compromises the welfare of future generations. The welfare of South Africa’s present population and more especially in the future will be greatly determined by the stock of natural resources available and the quality of the environment. Currently, the production processes deplete natural resources. Concern with the supposed increasing scarcity of gold in South Africa, and the possibility of running out of gold, has become a source of concern. South Africa’s gold reserves (gold in the ground that can be extracted profitably) are becoming depleted at an alarming rate. Most reserves are already exhausted; and the costs involved in mining lower-grade ore, and deposits located very deep in the ground, are becoming excessive. In light of this, this study sought to test the applicability of the Hotelling rule in South Africa. In order to empirically test the Hotelling rule, the study was guided by previous literature that had sought to test it. In this regard, the study used both descriptive and inferential statistics. The study has three data analysis chapters. The first two presented and examined the time series properties of gold prices, gold production and gold consumption. The third data analysis chapter examined the relationship between gold price and interest rates. In the first two data analysis chapters, visual inspection, growth rates, variance ratio tests and advanced unit root tests were used to examine the time series properties of gold prices, gold production and gold consumption. Results showed that the behaviour of the gold price series and gold production series in South Africa have a behaviour that is socially optimal. This is in line with the Hotelling rule. The rule predicts exponentially increasing resource prices and this result in mineral resources following the path of the positive trend. The positive trend is prompted by the increasing price reflecting the increasing scarcity of the resource. However, consumption trends were seen to be violating the Hotelling rule. The Hotelling rule predicts that the price increases until it eventually reaches the choke price, where the quantity demanded decreases to zero. However, in contrast to this, results showed that the demand for gold has been increasing instead of decreasing. This is not in line with the Hotelling rule. Furthermore the relationship between interest rate and gold price was negative and this suggested that the price of gold was not rising at the rate of the interest rate. The results of the study suggested that gold production is not following a social optimally path. The study recommended that the government come up with measures that prolong the lifespan of the gold reserves. These included research and development to promote technological innovations in the mining sector. This may make it possible for firms to access lower-grade ores. The study also recommended that since the Hotelling rule partly applied in the gold sector, there is a need to adopt some other theoretical measures that can ensure that the proceeds from the gold taxes are used in the most effective way.

No description available.

Thesis. 1976. Ph.D.--Massachusetts Institute of Technology. Dept. of Economics. / Microfiche copy available in Archives and Dewey. / Includes bibliographical references. / Ph.D.

Dissertation (PhD)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: The efficient management of renewable resources may ensure sustainable income to communities and countries. In the past the mathematical modelling used in the management decisions, in South Africa, was based on biological considerations only. In this thesis we include economic factors in the models and aim to determine steady state harvesting levels such that a maximum present value of all future revenues may be reached. A bio-economical approach is followed throughout the study and applied to the South African Cape Rock Lobster (Jasus lalandii) resource. We first address the problem using the simplest surplus production models. The model is applied to the Cape Rock Lobster, finding that the economical factors do indeed influence the steady state results, emphasising that they should be incorporated in the modelling process. A more descriptive two-sex-delay-difference model is then applied, which includes delay times for juveniles to reach sexual maturity and distinguishes between sexes. Yet further involved stage-class models are also studied and we propose a solution to the non-linear programming problem reached. These models may assist decision makers in future as knowledge on, for example, the growth of the two sexes, proper size limits and the influence of price differences are gained. Finally, we propose a harvesting strategy where catch is taken from alternative spatial lanes and apply here results from reaction diffusion theory. This theoretical approach might provide guidelines to new and underdeveloped fisheries in future, but also influence current inshore fisheries towards new management strategies. / AFRIKAANSE OPSOMMING: Die doeltreffende bestuur van hernubare hulpbronne kan 'n volhoubare ekonomiese opbrengs aan gemeenskappe en lande verseker. In die verlede is die wiskundige modelle wat in die besluitnemingsproses gebruik is, in Suid Afrika, gebaseer op biologiese oorwegings alleen. In hierdie studie word ook ekonomiese faktore in die modelle ingesluit en word ewewigstoestande bepaal vir vangste, sodanig dat 'n maksimum huidige waarde van toekomstige inkomste uit 'n vissery bereik word. 'n Bio-ekonomiese benadering word deurgaans gevolg en modelle word toegepas op die Suid-Afrikaanse Weskus Kreefbron (Jasus lalandii). Die studie begin deur basiese surplus produksie modelle te gebruik. Die resultate van die toepassing op die Weskus Kreefbron toon dat die ekonomiese faktore 'n groot invloed op die voorgestelde ewewigstoestand van die populasie het. Dit benadruk dus die feit dat hierdie faktore in die modelleringsproses ingesluit behoort te word. Meer beskrywende twee-geslag-vertragings-verskil modelle word daarna toegepas, en sluit in 'n vertragings periode vir vis om 'n volwasse stadium te bereik. Hierdie tydfaktor verskil dikwels vir mannetjies en wyfies en daarom word hier 'n twee-geslag model gebruik. Meer gevorderde klasse modelle word ook bespreek. Ons stel 'n oplossing vir hierdie nie-lineêre programmeringsprobleem voor. Hierdie gevorderde modelle mag in die toekoms handige hulpmiddels wees wanneer inligting rakende 'n spesie gesoek word. Sulke inligting mag insluit die groeitempos van mannetjies en wyfies, geskikte grootte beperkings vir vangste en die invloed van prysverskille vir verskillende groottes vis. 'n Nuwe vangste strategie word ook voorgestel waar vangste slegs geneem word uit alternatiewe ruimtelike bane en pas ons hier resultate uit die reaksie-diffusie teorie toe. Hierdie teoretiese oplossings mag riglyne bied wanneer nuwe visserye in die toekoms ontgin word, maar ook huidige visserye beïnvloed in die rigting van 'n nuwe bestuur strategie.