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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.
631

Geographical information systems and natural resource management in Zambia : a dissertation presented in partial fulfilment of the requirements for a Masters degree in Environmental Management at Massey University, Palmerston North, New Zealand

Mwape, Ackim January 2010 (has links)
Natural resources play a critical role in the welfare of developing countries. In Zambia, even though its vast natural resources have been important to its economy as well as its people, their exploitation has resulted in severe land and environmental degradation in most parts of the country. Reliable information as to the exact extent and degree of natural resources problems is critically lacking. For effective control and management of these natural resources problems, timely, up‐to‐date, accurate and complete spatial data are needed. The integrated application of Geographical Information Systems (GIS) and remote sensing to model natural resources management data, especially at regional level, is presented in this dissertation. Three case studies in Zambia are presented and free, internet‐based, datasets are used to demonstrate the application of GIS to support natural resource management decisions in Zambia. The results of the case studies show that while data‐gathering obstacles remain in the use of GIS in Zambia, the systems can be used successfully to fill gaps in decision‐making in natural resources management. The results of the case studies have been used to make recommendations as a way forward for the use of GIS and remote sensing data in natural resource management in Zambia. Finally, selected technical issues associated with data access, data incompatibility and data accuracy are identified as important areas of future research.
632

Collective Action and Equity in Nepalese Community Forestry

Shrestha, Krishna K January 2005 (has links)
Doctor of Philosophy (PhD) / This thesis critically analyses collective action processes and outcomes in Community Forestry through the concept of embeddedness. This research focuses on the questions of when people cooperate, how and why collective action emerges and evolves, and what leads or does not lead to equitable outcomes. The thesis makes a fundamental distinction between equality and equity. The research focuses specifically on the Nepalese experience with Community Forestry (CF), which is regarded as one of the most progressive CF programs being implemented in one of the poorest countries in the world. The thesis adopts an integrated research approach involving multiple actors, scales and methods with a focus on local level CF processes and forest users. This study considers the Forest Users Group (FUG) as a unit for analysis. Field work was conducted in three FUGs from the mid-hill region of Nepal over seven months between August 2001 and February 2002. The field research moves downwards to the household level and upward to the district, national and international level actors. It employs a combination of the process analysis and actor oriented approach and qualitative and quantitative methods to understand how CF is being driven, who is driving it and why CF is advancing in a certain direction. The study shows that the emergence, evolution and outcomes of collective action in CF are complex and varied due to specific and changing socio-cultural, economic, political and ecological contexts. Without understanding the complexities, in which peoples’ motivation and collective action are embedded, we cannot explain the emergence and evolution of collective action in CF. This thesis challenges the rational choice tradition and some key points of Common Property Regimes (CPR) theory and highlights the concept of embeddedness in participatory natural resource management. The thesis highlights the problem of decentralised CF policy and the forest bureaucracy. Decentralisation universally imposes a formal democratic system based on equality without acknowledging unequal societies. In Nepal, there has been little reorganisation of the forest bureaucracy. Despite being an international model for community forestry, in Nepal the existing bureaucracy has been unable or unwilling to transfer knowledge to forest users. The thesis concludes by stating the need to avoid the pitfalls of some democratic principles associated with standardisation and formalism. This means transforming bureaucratic norms and ideology. Context is central for the sustainable and equitable management of natural resources. It must be further researched and applied in decision-making if CF is going to achieve its potential to improve the condition of forests and the welfare of rural people.
633

Analyse comparée de l'usage de la modélisation d'accompagnement pour faciliter la gestion adaptative de l'eau agricole au Bouthan / Comparative analysis of using companion modelling to facilitate adaptive management of agricultural water in Bhutan

Gurung, Tayan Raj 08 April 2011 (has links)
À venir / The customary regime of NRM in Bhutan faces greater challenges from economic development, rapid transformation of social values, local institutions and traditional perceptions on NR. Although Bhutan is projected rich in water resource for hydropower potentials, water for agriculture and domestic use is fast becoming scarcer and highly contested. As the water becomes scarce the people living in highlands are most severely affected. A detail diagnostic study of two communities, Lingmuteychu depedent of irrigated rice and Kengkhar depedent on dryland farming presents two situations of water resource issues. In Lingmuteychu the conflict of irrigation water sharing for cultivation of rice among seven villages has been inflicting restentment in all aspect of society. In contrary, in Kengkhar has been facing drinking water scarcity as the natural spring ponds dry, which forces people to walk from more than five hours to fetch water from the river. In these two sites Companion Modelling was applied to enhance understanding of water resource management dynamics and improve shared communication and learning to facilitate adaptative management dynamics and improve shared communication and learning to facilitate adaptative management strategies. The study provides as comparison of the process followerd in two sites with analysis of impacts and effects from the process. The research illustrates fow ComMod process help develop trust and and commitment in the conflicting community and pave pathways to develop social capital for adaptive management of water resource. The process was able to foster shared learning and co-construct collective actions which were implementable. The research also revealed the important role of the researchers in furthering and sustaining newly achieved cooperation. The ABMs provided an opportunity to re-create different water resource management strategies which could be used as options for the community. The research also demonstrates the feasibility of applying the ComMod approach in different fields of NRM.
634

Developing Behavioral Indices of Population Viability: A Case Study of California Sea Lions in the Gulf of California, Mexico

January 2012 (has links)
abstract: Despite years of effort, the field of conservation biology still struggles to incorporate theories of animal behavior. I introduce in Chapter I the issues surrounding the disconnect between behavioral ecology and conservation biology, and propose the use of behavioral knowledge in population viability analysis. In Chapter II, I develop a framework that uses three strategies for incorporating behavior into demographic models, outline the costs of each strategy through decision analysis, and build on previous work in behavioral ecology and demography. First, relevant behavioral mechanisms should be included in demographic models used for conservation decision-making. Second, I propose rapid behavioral assessment as a useful tool to approximate demographic rates through regression of demographic phenomena on observations of related behaviors. This technique provides behaviorally estimated parameters that may be applied to population viability analysis for use in management. Finally, behavioral indices can be used as warning signs of population decline. The proposed framework combines each strategy through decision analysis to provide quantitative rules that determine when incorporating aspects of conservation behavior may be beneficial to management. Chapter III applies this technique to estimate birthrate in a colony of California sea lions in the Gulf of California, Mexico. This study includes a cost analysis of the behavioral and traditional parameter estimation techniques. I then provide in Chapter IV practical recommendations for applying this framework to management programs along with general guidelines for the development of rapid behavioral assessment. / Dissertation/Thesis / M.S. Biology 2012
635

Two Essays on the Trade-Offs Between Multiple Policy Objectives of Environmental Management Efforts

January 2012 (has links)
abstract: Environmental agencies often want to accomplish additional objectives beyond their central environmental protection objective. This is laudable; however it begets a need for understanding the additional challenges and trade-offs involved in doing so. The goal of this thesis is to examine the trade-offs involved in two such cases that have received considerable attention recently. The two cases I examine are (1) the protection of multiple environmental goods (e.g., bundles of ecosystem services); and (2) the use of payments for ecosystem services as a poverty reduction mechanism. In the first case (chapter 2), I build a model based on the fact that efforts to protect one environmental good often increase or decrease the levels of other environmental goods, what I refer to as "cobenefits" and "disbenefits" respectively. There is often a desire to increase the cobenefits of environmental protection efforts in order to synergize across conservation efforts; and there is also a desire to decrease disbenefits because they are seen as negative externalities of protection efforts. I show that as a result of reciprocal externalities between environmental protection efforts, environmental agencies likely have a disincentive to create cobenefits, but may actually have an incentive to decrease disbenefits. In the second case (chapter 3), I model an environmental agency that wants to increase environmental protection, but would also like to reduce poverty. The model indicates that in theory, the trade-offs between these two goals may depend on relevant parameters of the system, particularly the ratio of the price of monitoring to participant's compliance cost. I show that when the ratio of monitoring costs to compliance cost is higher, trade-offs between environmental protection and poverty reduction are likely to be smaller. And when the ratio of monitoring costs to compliance costs is lower, trade-offs are likely to be larger. This thesis contributes to a deeper understanding of the trade-offs faced by environmental agencies that want to pursue secondary objectives of protecting additional environmental goods or reducing poverty. / Dissertation/Thesis / M.S. Biology 2012
636

Essays on the links between natural resources, corruption, taxation and economic growth

Veisi, Mohsen January 2017 (has links)
This thesis studies the poor development performance of resource-rich developing economies, known as the resource curse. In the first chapter we provide a comprehensive literature review of the topic and the channels through which resource abundance can result in the resource curse. Issues of corruption and governance have been emphasised to be the main driver of the resource curse. This has been illustrated by a negative relationship between resource abundance and corruption control in the literature. However, there is a gap in how natural resources facilitate corruption. In the second chapter, using empirical analysis, we study the role of taxation in the relationship between natural resources and corruption. Taxation is usually seen as a social contract between citizens and government -- people pay taxes and in return they hold their government accountable for efficient allocation of their taxes. Resource abundance shifts the reliance of government from tax incomes to resource rents. People therefore, have no sustainable mechanism to hold their government responsible for corruption and wrongdoings inside public institutions. Using different econometric methods, Pooled OLS, Fixed Effects and 3SLS, our results show that natural resource revenues crowd out incomes from tax revenues. Meanwhile, taxation has a positive and significant impact on the control of corruption throughout our analysis. The results suggest that resource-rich developing countries should invest in building their tax systems to increase their non-resource tax revenues. This will increase state capacity and demand for accountability in the public sector among citizens and hence decreases corruption. Related to our second chapter, in the third chapter we study a cash transfer programme, known as oil-to-cash, which has gained support as a tool to re-establish taxation and fight corruption. Under such a plan, resource revenues are distributed directly among the public and then each citizen is taxed optimally. Through this, government relies directly and fully on its citizens for its income. Hence, taxation is reinstated and the social contract is revived. Within a general equilibrium model we show how this happens and what the implications are of the oil-to-cash programme for economic growth. Our results clearly show how corruption results in a resource curse. Furthermore, the model explains the variation that is seen in the degree of the resource curse across countries. The study also analyses the practical barriers of the oil-to-cash plan. The study suggests that parallel to (or even prior to) such a plan countries need to invest in building their tax system and increasing their administrative capacities.
637

Bioeconomic Models and Sustainable Use of Marine Resources: Three Case Studies

January 2014 (has links)
abstract: This dissertation consists of three substantive chapters. The first substantive chapter investigates the premature harvesting problem in fisheries. Traditionally, yield-per-recruit analysis has been used to both assess and address the premature harvesting of fish stocks. However, the fact that fish size often affects the unit price suggests that this approach may be inadequate. In this chapter, I first synthesize the conventional yield-per-recruit analysis, and then extend this conventional approach by incorporating a size-price function for a revenue-per-recruit analysis. An optimal control approach is then used to derive a general bioeconomic solution for the optimal harvesting of a short-lived single cohort. This approach prevents economically premature harvesting and provides an "optimal economic yield". By comparing the yield- and revenue-per-recruit management strategies with the bioeconomic management strategy, I am able to test the economic efficiency of the conventional yield-per-recruit approach. This is illustrated with a numerical study. It shows that a bioeconomic strategy can significantly improve economic welfare compared with the yield-per-recruit strategy, particularly in the face of high natural mortality. Nevertheless, I find that harvesting on a revenue-per-recruit basis improves management policy and can generate a rent that is close to that from bioeconomic analysis, in particular when the natural mortality is relatively low. The second substantive chapter explores the conservation potential of a whale permit market under bounded economic uncertainty. Pro- and anti-whaling stakeholders are concerned about a recently proposed, "cap and trade" system for managing the global harvest of whales. Supporters argue that such an approach represents a novel solution to the current gridlock in international whale management. In addition to ethical objections, opponents worry that uncertainty about demand for whale-based products and the environmental benefits of conservation may make it difficult to predict the outcome of a whale share market. In this study, I use population and economic data for minke whales to examine the potential ecological consequences of the establishment of a whale permit market in Norway under bounded but significant economic uncertainty. A bioeconomic model is developed to evaluate the influence of economic uncertainties associated with pro- and anti- whaling demands on long-run steady state whale population size, harvest, and potential allocation. The results indicate that these economic uncertainties, in particular on the conservation demand side, play an important role in determining the steady state ecological outcome of a whale share market. A key finding is that while a whale share market has the potential to yield a wide range of allocations between conservation and whaling interests - outcomes in which conservationists effectively "buy out" the whaling industry seem most likely. The third substantive chapter examines the sea lice externality between farmed fisheries and wild fisheries. A central issue in the debate over the effect of fish farming on the wild fisheries is the nature of sea lice population dynamics and the wild juvenile mortality rate induced by sea lice infection. This study develops a bioeconomic model that integrates sea lice population dynamics, fish population dynamics, aquaculture and wild capture salmon fisheries in an optimal control framework. It provides a tool to investigate sea lice control policy from the standpoint both of private aquaculture producers and wild fishery managers by considering the sea lice infection externality between farmed and wild fisheries. Numerical results suggest that the state trajectory paths may be quite different under different management regimes, but approach the same steady state. Although the difference in economic benefits is not significant in the particular case considered due to the low value of the wild fishery, I investigate the possibility of levying a tax on aquaculture production for correcting the sea lice externality generated by fish farms. / Dissertation/Thesis / Doctoral Dissertation Biology 2014
638

Scenario Planning for Sustainable Dark Skies: Altering Mental Models and Environmental Attitudes Through Scenario Planning

January 2016 (has links)
abstract: Recent research within the field of natural resource management has been devoted to studying the cognitive structures, called mental models, that guide people’s thoughts, actions, and decision-making. Artificial lighting threatens the sustainability of pristine night skies around the world and is growing worldwide at an average rate of six-percent per year. Despite these trends, stakeholders’ mental models of night skies have been unexplored. This study will address this gap by eliciting stakeholders’ mental models of dark skies. Scenario planning has become a pervasive tool across diverse sectors to analyze complex systems for making decisions under uncertainty. The theory of scenario planning hypothesizes that scenario planning contributes to learning and improves upon participants’ mental models. However, there have been scant empirical studies attempting to investigate these two claims. Stakeholders’ mental models of dark skies were mapped while simultaneously testing the hypotheses that participation in scenario planning results in more complex mental models and alters environmental attitudes. Twenty-one Arizona stakeholders participated in one of two workshops during September 2016. Three identical surveys were given to measure knowledge, environmental attitudes and mental model change during the workshops. Knowledge gain peaked during the introductory lecture and continued to increase during the workshop. Scenario planning increased participants’ environmental attitudes from anthropocentric to nature-centered and was found to have a significant positive impact on dark sky advocates’ change in mental model complexity. The most prominent drivers affecting dark skies were identified using social network analysis of the pre and post mental models. The most prominent concepts were altered significantly from pre to post workshop suggesting that scenario planning may aid practitioners in understanding exogenous factors to their area of expertise. These findings have critical theoretical and managerial implications of mental model alteration, environmental attitudes, and the future of Arizona’s night skies. A revised theoretical framework is offered to include environmental attitudes into the theory of scenario planning and a conceptual framework was created to illustrate the most salient drivers affecting or being affected by dark skies. / Dissertation/Thesis / Masters Thesis Community Resources and Development 2016
639

Microhabitat and Movement Assessment for Northern Mexican Gartersnakes (Thamnophis eques megalops) at Bubbling Ponds Hatchery, Arizona

January 2017 (has links)
abstract: Species conservation requires an understanding of the habitats on which that species depends as well as how it moves within and among those habitats. Knowledge of these spatial and temporal patterns is vital for effective management and research study design. Bubbling Ponds Hatchery in Cornville, Arizona, supports a robust population of the northern Mexican gartersnake (Thamnophis eques megalops), which was listed as threatened under the Endangered Species Act in 2014. Natural resource managers are interested in understanding the ecology of gartersnakes at this site to guide hatchery operations and to serve as a model for habitat creation and restoration. My objectives were to identify habitat selection and activity patterns of northern Mexican gartersnakes at the hatchery and how frequency of monitoring affects study results. I deployed transmitters on 42 individual gartersnakes and documented macro- and microhabitat selection, daily and seasonal activity patterns, and movement distances. Habitat selection and movements were similar between males and females and varied seasonally. During the active season (March–October), snakes primarily selected wetland edge habitat with abundant cover and were more active and moved longer distances than during other parts of the year. Gestating females selected similar locations but with less dense cover. During the inactive season (November–February), snakes were less mobile and selected upland habitats, including rocky slopes with abundant vegetation. Snakes displayed diurnal patterns of activity. Estimates of daily distance traveled decreased with less-frequent monitoring; a sampling interval of once every 24 hours yielded only 53–62% of known daily distances moved during the active season. These results can help inform management activities and research design. Conservation of this species should incorporate a landscape-level approach that includes abundant wetland edge habitat with connected upland areas. Resource managers and researchers should carefully assess timing and frequency of activities in order to meet project objectives. / Dissertation/Thesis / Masters Thesis Applied Biological Sciences 2017
640

Rates of Lateral Expansion of Biological Soil Crusts

January 2017 (has links)
abstract: Biological soil crusts (biocrust) are photosynthetic communities of organisms forming in the top millimeters of unvegetated soil. Because soil crusts contribute several ecosystem services to the areas they inhabit, their loss under anthropogenic pressure has negative ecological consequences. There is a considerable interest in developing technologies for biocrust restoration such as biocrust nurseries to grow viable inoculum and the optimization of techniques for field deployment of this inoculum. For the latter, knowledge of the natural rates of biocrust dispersal is needed. Lateral dispersal can be based on self-propelled motility by component microbes, or on passive transport through propagule entrainment in runoff water or wind currents, all of which remain to be assessed. I focused my research on determining the capacity of biocrust for lateral self-propelled dispersal. Over the course of one year, I set up two greenhouse experiments where sterile soil substrates were inoculated with biocrusts and where the lateral advancement of biocrust and their cyanobacteria was monitored using time-course photography, discrete determination of soil chlorophyll a concentration, and microscopic observations. Appropriate uninoculated controls were also set up and monitored. These experiments confirm that cyanobacterial biological soil crusts are capable of laterally expanding when provided with presumably optimal watering regime similar to field conditions and moderate temperatures. The maximum temperatures of Sonoran Desert summer (up to 42 °C), exacerbated in the greenhouse setting (48 °C), caused a loss of biomass and the cessation of lateral dispersal, which resumed as temperature decreased. In 8 independent experiments, biocrust communities advanced laterally at an average rate of 2 cm per month, which is half the maximal rate possible based on the instantaneous speed of gliding motility of the cyanobacterium Microcoleus vaginatus. In a span of three months, populations of M. vaginatus, M. steenstrupii, and Scytonema spp. advanced 1 cm/month on average. The advancing crust front was found to be preferentially composed of hormogonia (differentiated, fast-gliding propagules of cyanobacteria). Having established the potential for laterally self-propelled community dispersal (without wind or runoff contributions) will help inform restoration efforts by proposing minimal inoculum size and optimal distance between inoculum patches. / Dissertation/Thesis / Masters Thesis Biology 2017

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