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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.
61

Can ICT Enhance Nature Conservation and Protected Area Management? A case study from Mongolia's Khuvsgol Lake National Park / 自然保護と保護区管理の推進に対するICTの役割に関する研究-モンゴル国フブスグル湖国立公園を事例に-

Guy McCarthy, Christopher 23 May 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(地球環境学) / 甲第21978号 / 地環博第185号 / 新制||地環||37(附属図書館) / 京都大学大学院地球環境学舎地球環境学専攻 / (主査)准教授 真常 仁志, 教授 舟川 晋也, 教授 西前 出 / 学位規則第4条第1項該当 / Doctor of Global Environmental Studies / Kyoto University / DGAM
62

The Response of a Predatory Fish, Ophiodon elongatus, to a Marine Protected Area: Variation in Diet, Catch Rates, and Size Composition

Anderson, Eric S 01 December 2016 (has links)
Marine Protected Areas (MPAs) are a management tool used to protect and sustain many ecologically and economically important fish species from overexploitation by recreational and commercial fishing. Lingcod (Ophiodon elongatus) and some of its prey species, such as rockfish (Sebastes spp.), are species that are protected from fishing in some California MPAs. Lingcod is an apex predator that consumes a variety of fish and invertebrate species. In this study, I sought to assess the effect of an MPA on the abundance, size and diet of Lingcod. I hypothesized that Lingcod in a no-take MPA would be more abundant and larger than Lingcod in an adjacent reference site (REF) that was open to fishing. Furthermore, I hypothesized that diet would differ between Lingcod in caught the MPA and Lingcod in the REF. I collected Lingcod from the Point Buchon State Marine Reserve (MPA) and an adjacent REF site that was open to fishing. I measured, weighed, sexed, and collected stomach contents from Lingcod using the gastric lavage (stomach pumping) technique. Then, I identified prey items from Lingcod stomach contents down to the lowest taxonomic level possible and quantified diet composition by percent by occurrence, percent by number, and percent by mass. Lingcod in the MPA consumed more fish prey items than Lingcod in the REF site. Lingcod in the REF consumed more cephalopod prey items than Lingcod in the MPA. I analyzed the four most common prey items (rockfish, anchovies, flatfish, and octopus) for nutritional content. My data suggest that Lingcod increased in size and abundance in a no-take MPA because they do not suffer from fishing mortality. However, a more nutritious diet could also contribute to a biologically significant advantage for Lingcod in the MPA. To address this would require further research focused on calculating the net energy (gross energy extracted from the prey item minus the energetic costs of handling and digesting the prey item) obtained by Lingcod from consuming different fish and cephalopod prey items. MPAs can be an effective management tool for protecting fish stocks, although, it is important to understand the interspecific interactions between predator and prey species to adaptively mange MPAs and the species that reside within them.
63

Newly designated Indigenous Protected and Conserved Areas in Canada’s North : another label for inequitable co-management agreements or an honest attempt to walk the road of reconciliation?

Seiferth, Carolin January 2022 (has links)
Inclusion of Indigenous communities and Traditional Ecological Knowledges (TEK) alongside reconciliation efforts feature in numerous plans and policies for nature and biodiversity conservation. But to what extent do these agreements present an honest attempt to equally share power and responsibility between Indigenous peoples and governance agencies in protected area management? In this thesis, I trace how including Indigenous communities and their TEK entered Canada’s policy discourse on nature conservation. I focus on the designation of Indigenous Protected and Conserved Areas (IPCAs), which presents Canada’s latest approach towards including Indigenous peoples in protected area management. Through a study of policy documents, I compare changes in Canadian governance agencies’ proposal of and motivations behind Indigenous peoples’ inclusion with insights from Indigenous communities’ documents related to Edéhzíe Protected Area and Thaidene Nëné Indigenous Protected Area. These documents offer insights into Indigenous stewardship practices, emphasize Indigenous self-governance as well as the role of TEK, Western science, and Indigenous languages in IPCA management. Although I conclude that Edéhzíe Protected Area and Thaidene Nëné Indigenous Protected Area present an honest attempt to equally share power and responsibility in IPCA management, I call on governance agencies to further centre Indigenous peoples’ ideas on stewarding biodiversity-rich places, grant rights to self-determination and self-governance, and restore justice.
64

Comparisons of Fish Species Inside and Outside of Marine Protected Areas off the South Central Coast of California

Rasmussen, David E 01 October 2010 (has links) (PDF)
COMPARISONS OF FISH SPECIES INSIDE AND OUTSIDE OF MARINE PROTECTED AREAS OFF THE SOUTH CENTRAL COAST OF CALIFORNIA David E. Rasmussen From 2004-2008 and 2008-2009 Cal Poly University researchers conducted two separate tag and recapture studies of nearshore fish populations along California’s central coast. Three locations were sampled that have experienced different degrees of fishing pressure. Big Creek MPA has been closed to all fishing from 1993 onwards and is the farthest from port of all locations. Cambria lies closest to port of the three locations and because of this has the highest fishing pressure. Piedras Blancas lies midway between Cambria and Big Creek. Portions of Cambria and Piedras Blancas were designated as MPAs in 2007. Sampling protocols of these two different studies differed in bait used and size of commercial fish trap. An experiment was conducted to simultaneously compare the different trapping and baiting protocols from the prior studies to find a conversion factor that related catch per unit effort (CPUE), length frequency distributions and captured fish diversity between the two studies, thus providing a means to connect the two data sets for stock assessments and baseline MPA monitoring. Our sampling showed no significant difference in mean fish length or diversity between the two protocols for the five most common nearshore fish species captured, and three of the five species showed no significant difference in CPUE. Cabezon (Scorpaenichthys marmoratus), showed a significantly lower CPUE (50.5%) using the MLPA monitoring protocols compared to the commercial fishing protocol and black and yellow rockfish (Sebastes chrysomelas) had a significantly higher CPUE (310%) using the MLPA monitoring protocol. These findings provide a means of maintaining data continuity across the entire sample region and inclusion of earlier projects in the analyses of nearshore fish populations of the region. With the linkage of these two studies we provide important baseline data for the Cambria MPA from before it was established in 2007. Fish populations were compared on a year-to-year basis within each location, and between the different locations. I found several main factors helped to explain differences in size and abundance across time within individual locations, and across the three locations. These factors were inherent differences in habitat, establishment of MPAs, and changes in fishing pressure and post-larval recruitment. Cabezon were largest within Big Creek, followed by Piedras Blancas and Cambria which held the smallest fish, suggesting that fishing pressure is influencing fish size. However, cabezon were more abundant at Cambria than either other location suggesting that location is influencing abundance. Within Cambria, we are seeing an MPA effect with abundance within the MPA staying stable while the reference site is declining. Gopher rockfish (Sebastes carnatus) and black and yellow rockfish had similar trends with size and abundance between locations. Big Creek and Piedras Blancas held the largest fish, while Cambria was smaller. Both rockfish species were most abundant at Big Creek, followed by Cambria then Piedras Blancas. Size for these species is likely influenced by fishing pressure, and abundance is likely influenced by both fishing pressure and location. Both species increased in abundance 2004-2009 at Cambria, and this could be due to improved levels of post-larval recruitment. There is also a possible MPA effect for gopher rockfish at Cambria with a near significant divergence in size of fish between the MPA and reference site. Kelp greenling (Hexagrammos decagrammus) were similar in size and abundance between all sampling locations. There is a possible MPA effect at Cambria, with a significantly higher abundance than the reference site; however this difference predates the MPA’s establishment but could have been exacerbated by it. Lingcod (Ophiodon elongatus) size did not vary significantly between sites, but they were the most abundant at Cambria, followed by Piedras Blancas, then Big Creek, suggesting that habitat is influencing abundance. There was also a possible MPA effect on abundance of lingcod at Cambria with the MPA having a significantly higher abundance than the reference site. Similarly to the kelp greenling, these differences predated the MPA, but could have been exacerbated by its establishment, and abundance within the MPA has stayed stable, while the reference site was declining. Big Creek and Piedras Blancas have similar Shannon-Weiner diversity values, while Cambria has significantly lower. However, after MPA establishment at Cambria, the MPA has attained significantly higher diversity levels than the reference site. Over the short period of time that the Piedras Blancas and Cambria MPA have been established the populations within them have changed. However, there are no discernable trends in size, abundance and diversity between the MPA and reference sites at both locations. It is likely that with these slower growing, long-lived fish species that it will take more years for differences between the sites to manifest themselves.
65

Spatial and Temporal Comparisons of Gopher Rockfish (Sebastes carnatus) Life History and Condition in South Central California

Meyers-Cherry, Natasha Leigh 01 December 2014 (has links) (PDF)
Recent studies have shown environmental factors influence life history traits in fishes. Understanding intraspecific variability of life history characteristics and condition is necessary to determine local fisheries management strategies. Gopher rockfish, Sebastes carnatus, comprise 50% of the estimated shallow nearshore recreational rockfish catch in California, yet insufficient local data exist regarding life history traits and condition of this species. Our study locally defines growth parameters (maximum size and age), size (age) at reproductive maturity, and condition (hepatosomatic indices) for gopher rockfish in south central California. The growth parameter values of gopher rockfish from our study are similar to previously published research. However, our data also indicate that the current local gopher rockfish stock in south central California reaches reproductive maturity at a larger size and an older age when compared to gopher rockfish sampled throughout central California (primarily in Monterey) between 1977-1982. Furthermore, we examined spatial and temporal differences in life history information, within and outside of two south central California Marine Protected Areas (MPAs) established in 2007, between two time periods. Our data show that the size and longevity of fish has increased after the establishment of MPAs.
66

How important are water sources to pastoralist movement in times of climate change? : A modelling approach.

Mischke, Max Louis January 2023 (has links)
Livestock grazing is an important part for the livelihood of a large part of the world’s population. While in some areas of the world water accessibility is often taken for granted, in arid regions this can be a limited resource. The central Asian country of Mongolia is one of the countries that sees excessive livestock grazing in an arid region. Nomadic pastoralism is widespread to ensure access to fresh water sources as well as pastures. These movement patterns are under ongoing research, but so far, the impact of water accessibility on these movement patterns has not been investigated. Specifically in the Great Gobi B Strictly Protected Area, pastoralists rely on water obtained from a variety of sources like lakes, rivers, and wells. I analysed camp usage and the availability of water for pastoralists to uncover current movement patterns and how these are influenced by water. I want to gain insight on how the distance to the closest water source influences camp usage and how this changes with seasonality and the size of the herd. For this I conducted Kruskal-Wallis and two-sided Pearson tests respectively. A potential overlap between wildlife and livestock was investigated since this might be a potential conflict and further leading to the spread of diseases. Furthermore, I modelled precipitation and temperature until the year 2050 to spot a potential redistribution of water in an already arid region. There was no correlation found between the seasons nor herd size and the distance to the closest and second closest water source. In my analysis, the overlap between wildlife and livestock was found only to a minor extend. Precipitation and temperature in the region were found to change only to a marginal degree from 2023 to 2050. Due to this, I identified the most important water sources and camps based on the analysisof the current data.
67

Protected Area Planning and Management: Supporting Local Stakeholder Participation with an Asset-Based, Biocultural Approach

Wengerd, Nicole M. 26 May 2018 (has links)
No description available.
68

Effects of fishing on a coral reef fish assemblage in Northeastern Brazil

De Moraes Carvalho, Felipe 15 February 2022 (has links)
Reef fisheries are important activities that support the livelihoods of millions of people. Reef fisheries exploit different habitats and typically target a diversity of species caught with a matching diversity of fishing gears. However, previous studies of reef fisheries have generally lacked detailed information on the catch and effort by gear and habitat type. In this dissertation, the sustainability of a coral reef fishery at the Marine Protected Area Costa dos Corais, Northeastern Brazil is assessed. In 1,833 landing interviews with local fishers, 100 fished species were identified and the total catch in kilograms for each species, the size composition of captured individuals and the habitat type exploited were recorded. First, the dissertation explores how fishing gears selected for distinct functional traits. A low competitive interaction between different gears was noted. Gears used in reef habitats selected for sedentary and benthic species, while gears used in coastal lagoons targeted highly mobile and pelagic. Second, the dissertation assesses how different gear affected the catch rates of coral reef fishes. Gears used on coral reef habitats had a more negative effect on catch rates than those used in coastal lagoons. The three gear types that affected catch rates more severely were hook and line, gillnet and cast net. Based on the results it is argued that the effects of reef fisheries on catch rates were highly depended on the vulnerability of target species. Finally, the dissertation assesses the ability of the fishing-down concept to assess the sustainability of the local fishery; the fishing-down is used to describe the process of moving away from catching large fish to progressively targeting smaller fish. I found strong support for the fishing-down, as fisheries decreased the average size of the fish assemblage and affected more heavily the catch rates of fishes with higher index of vulnerability. Overall results show that fisheries management should focus on the conservation of vulnerable taxa that are responsible for key ecological processes in coral reefs such as herbivory and coral predation. The decision-making process on management measures must be based on clear discussions with all stakeholders involved. / Doctor of Philosophy / Coral reefs are one of the richest environments on the planet, but overfishing threatens their conservation. Reef fishers use many techniques, or fishing gears, such as hook and line and nets, to catch a high diversity of fish species. Reef fisheries are often unsustainable as fishers are allowed to employ high levels of effort. Thus, studies are needed to assess the sustainability of coral reef fisheries and determine which gears are more negative to reef fishes. In a series of three studies, I investigated how reef fisheries affected fish communities in Northeastern Brazil. I used a total of 1,833 interviews with fishers in which I recorded the total catch for each species, obtained size of fish individuals, and asked about the environment that was exploited, coral reefs or coastal lagoons. First, I evaluated how the different gears selected for groups of species with unique life-history characteristics, such as size, mobility and period of activity. I found that gears such as hook and line and harpoon selected for species with sedentary traits that live near the bottom of the ocean, whereas nets selected for very mobile species that inhabit surface waters. In general, fishers did not compete for the same resources with different gears. Second, I assessed how the different gears affected the relative abundance of coral reef fishes. The three gear types that affected more heavily the relative abundance of fishes were hook and line, gillnet and cast net. I argue that the negative effects occurred because these gears caught species with characteristics that made them vulnerable to exploitation, such as slow body growth. Third the dissertation assesses the ability of the fishing-down concept to assess the sustainability of the local fishery; the fishing-down is used to describe the process of moving away from catching large fish to progressively targeting smaller fish. I found strong support for the fishing-down as the studied fisheries impacted the size and the abundance of local fishes. My results suggest that fisheries management should focus on the conservation of vulnerable fish responsible for key ecological processes such as herbivory and coral predation. The decision-making process regarding fisheries management must also be based on clear discussions with all stakeholders involved.
69

Visitor Impact Assessment and Management for Protected Areas in Central and South America

Farrell, Tracy Ann 06 January 2000 (has links)
Ecotourism and protected area visitation have been steadily increasing in recent years in Central and South America, inevitably resulting in natural resource impacts. The consequences of such impacts may include natural resource degradation, diminished aesthetic qualities, or decreased functionality of certain facilities like recreation sites and trails. Recreation ecology and visitor impact management expertise and tools are available to help balance the potentially conflicting management goals of protecting natural resources and permitting visitation but such knowledge has not been widely used in Central and South America. The goals of this research were to characterize certain visitor-related natural resource impacts and to determine how these impacts could be assessed and managed in Central and South America. The research included case studies of eight protected areas in Costa Rica and Belize, trail impact assessment research at Torres del Paine National Park in Chile, and development of a new visitor impact assessment and management framework, presented as three papers intended for journal submission. The first paper had two objectives: 1) to identify visitor-related natural resource impacts at selected protected areas in Costa Rica and Belize to increase awareness about visitor impact problems, and 2) to apply and compare rapid trail and recreation site impact assessment procedures to provide study site managers with impact data and impact assessment procedures. A variety of natural resource impacts were reported by interview subjects and recorded by rapid assessment procedures. The management utility of the rapid trail and recreation site impact assessment procedures were compared and discussed and the need for developing additional rapid assessment procedures to evaluate other resource impacts reported by protected area managers was also identified. The intent of the second paper was to investigate trail impacts at Torres del Paine National Park. Study objectives included measuring the frequency and magnitude of selected trail impacts, and comparing the relative impact contribution of the amount of use, vegetation type, trail position and trail grade on common condition indicators such as width and incision. Findings somewhat contradicted those of other studies, revealing that amount of use significantly contributed to trail width and incision. However, findings also indicated that vegetation type and trail grade contributed to number of informal trails and trail incision, respectively. A variety of management strategies were recommended and suggestions were provided for future monitoring studies. The purpose of the third paper was to propose a new visitor impact assessment and management framework that would provide managers with a feasible means of addressing visitor impact management concerns for selected protected areas in Central and South America. The Protected Areas Impact Assessment and Management (PAIAM) framework was adapted from existing frameworks like carrying capacity and the Limits of Acceptable Change to provide a simple, cost-effective and relatively quick decision making process. PAIAM analyzes visitor impacts using an expert panel and incorporates stakeholders and local residents into decision making. This study experimentally applied the new framework in Mexico and compared PAIAM to existing frameworks. The focus of this dissertation is on Central and South America since they are heavily visited ecotourist regions that could potentially benefit from applying recreation ecology and visitor impact expertise and tools to protected area management. This research demonstrated that a variety of visitor impacts are affecting natural resources and visitor facilities like trails and recreation sites at selected protected areas in Central and South America. This research also developed and applied rapid impact assessment procedures and visitor impact frameworks for use in Central and South American protected areas. / Ph. D.
70

Exploring Visitors: Using the Theory of Planned Behavior to Understand Visitor Behavior and Improve the Efficacy of Visitor Information in Haleakalā National Park

Reigner, Nathan P. 30 December 2008 (has links)
Resource and visitor experience degradation in Haleakalā National Park resulting from recreational use of the Pools of 'Ohe'o has led park officials to discourage visitor use of the pools. This study uses the Theory of Planned Behavior (TPB) to examine relationships among visitors' attitudes, subjective norms, and perceived behavioral control with regard to exploring the pools, their intentions to explore, and their actual behaviors while visiting the pools. Further, this study examines the influence of persuasive messages on visitors' behavior at the pools. Persuasive message treatments emphasize either the dangers of exploring the Pools of 'Ohe'o or resource protection and visitor experience impacts of recreational use at the pools. Through regression analysis of attitudes, norms, and perceived behavioral control with intention to explore, TPB is generally found to be an effective model for understanding visitor behavior at 'Ohe'o's Pools, particularly when visitors are exposed to persuasive messages. Results of analysis of variance indicate that the TPB model components of attitudes and subjective norms with regard to traveling companions and National Park Service officials are influenced by exposure to the persuasive treatment messages. Additionally, both intention to explore the pools and observed exploration behavior are significantly lower among those visitors receiving any persuasive treatment message. Thus, results of this research generally support the individual relationships assumed within TPB. With identification of the most influential components of visitor behavior, as understood through the TPB model developed in this study, managers of Haleakalā National Park will be able to develop and apply persuasive interpretive messages that maximize safe and sensitive visitor recreational behavior at the Pools of 'Ohe'o. / Master of Science

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