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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.
341

Quantifying the Environmental Performance of a Stream Habitat Improvement Project

Morse, Cody 01 August 2018 (has links)
River restoration projects are being installed worldwide to rehabilitate degraded river habitat. Many of these projects focus on stream habitat improvement (SHI), and an estimated 60%of the 37,000 projects listed in the National River Restoration Science Synthesis Program focus on SHI for salmon and trout species. These projects frequently lack a sufficient monitoring program or account for the environmental costs associated with SHI. The present study used life cycle assessment (LCA) techniques and topographic effectiveness monitoring to quantify environmental costs on the basis of geomorphic change. This methodology was a novel approach to assessing the cost-benefit relationship of SHI. To test this methodology, two phases of the Lower Scotts Creek Floodplain and Habitat Enhancement Project (LSCR) were used as a case study. The LSCR was a SHI project installed along the northern coast of Santa Cruz County, California, USA. A limited scope LCA was used to quantify the life cycle impacts of raw material production, materials transportation, and on-site construction. Once these baseline results were produced, a topographic monitoring program was used to quantify the topographic diversity index (TDI) in pre- and post-project conditions. The TDI percent change was used to scale the baseline LCA results, which quantified the environmental impacts based on geomorphic change. Phase II outperformed phase I. Phase I had greater cumulative environmental impacts and experienced a 7.7 % TDI increase from pre- to post-project conditions. Phase II had 43% less cumulative environmental impacts and experienced a 7.9% TDI increase from pre- to post-project conditions. The impacts in phase I were greater because of the amount of material excavated to create off-channel features, which were a key feature of the LSCR. A scenario analysis also was conducted within the LCA component of this study. The scenario analysis suggests that life cycle impacts could be reduced by 30%-65% by using the accelerated recruitment method in place of importing materials to build large wood complexes. The results of this study suggest that managers may improve the environmental performance of SHI projects by: (1) using the accelerated recruitment method to introduce larger key pieces to the channel, reducing the need to import materials; (2) using nursery grown plants as opposed to excavating plants for revegetation; (3) minimizing fuel combustion in heavy equipment and haul trucks by ensuring clear access to the channel and streambank, using small engine equipment to clear access corridors during site preparation, running more fuel-efficient machinery or bio-fuel powered machinery, and by attempting to minimize haul distances by sourcing materials locally; and (4) utilizing a “franken-log” design (a ballasted LWC configuration with a rootwad fastened to the downstream end of a log) in LWCs which led to favorable TDI change. This study concluded that LCA could be a valuable tool for monitoring SHI and river restoration projects and that further research of the TDI analysis is justified.
342

The effectiveness of biosphere reserve as a tool for sustainable natural resource management in Vhembe District Municipality, Limpopo Province, South Africa

Mphidi, Mosima Florina 22 October 2019 (has links)
MENVSC / Department of Geography and Geo-Information Sciences / The purpose of this study was to contribute towards a better understanding of the effectiveness of Biosphere Reserve as a tool in managing natural resources in the Vhembe District Municipality (VDM), Limpopo Province of South Africa. There are limited documented materials for a better understanding of the effectiveness of Biosphere Reserve (BR) as a tool in managing natural resources in the Vhembe District Municipality (VDM). As a result, this study was undertaken to bridge this gap and to discover new insights to assist in understanding the effectiveness of BR as a tool in managing natural resources. This study adopted a pragmatic research approach, which is a mixture of the qualitative and quantitative research approaches, wherein data were collected using primary and secondary sources. Both primary and secondary data were used, in order to obtain information concerning the effectiveness of biosphere reserve in the study area. Primary data were obtained using a combination of methods, including participatory rural appraisal (PRA) tools and techniques, and informal and formal surveys. The secondary data was collected from desk-based examination of relevant documentation relating to conservation of the Biosphere Reserves areas. The documents included previous reports from Greenest Municipality Competition (GMC) results for all local municipalities from 2012 to 2017, Management Effective Tracking Tool (METT-SA) from 2016 to 2018, and previous research data on conservation. The results obtained revealed that Biosphere Reserve (BR) is an effective tool for the conservation of natural resources within Vhembe District, South Africa. This is because natural resources are taken into consideration when there are developments and projects being undertaken. Furthermore, the communities in Vhembe District Municipality benefit from the programmes and projects aimed at conserving natural resources within the VBR. The study also revealed that there are environmental challenges within the Vhembe Biosphere Reserve due to mining activities, climate change, developments in natural resources and deforestation, which require the enforcement of by-laws and programmes and projects aimed at conserving natural resources. / NRF
343

Examining Employee Motivation, Environmental Systems, and Corporate Social Responsibility in Proenvironmental Behavior

Warrick, Brian 01 January 2016 (has links)
The World Health Organization has pointed to climate change as the most significant issue in the 21st century as a result of greenhouse gas emissions and environmental pollution. Organizations are leaning toward corporate social responsibility (CSR) and environmental management systems (EMS) to reverse the current trend; however, these efforts are often ineffective or pooly implemented. The purpose of this quantitative study was to determine the extent to which employees' proenvironmental behavior relates to their protection motivation and organizational identification, as well as their perception and knowledge of the organization's CSR and EMS, respectively. Using social identity as the theoretical framework, this research addressed how organizational and intrapersonal factors influence employees' proenvironmental behavior. One hundred-twenty employees from American-based organizations completed an online survey measuring self-assessed proenvironmental behaviors, among other variables. The results from a Pearson correlation analysis indicated that all of the independent variables had a significant positive relationship with employee proenvironmental behaviors. Multiple regression analysis showed that while each variable was a significant predictor of proenvironmental behaviors, only the economic dimension of CSR (β = .300, p = .014) and the self-efficacy dimension of protection motivation (β = .269, p = .037) significantly contributed to the model. Leaders' use of the findings may lead to positive social change through improved environmental performance in the form of decreased pollution, a more efficient use of natural resources, and reduced greenhouse gas emissions, all toward a more sustainable future.
344

Vegetation, Environmental Characteristics, and their Relationships: Variation within the Annually Flooded Riparian Zones of the John Day River Basin, Oregon

Hartsfield, Samuel J. 13 February 2009 (has links)
I hypothesized that vegetation and physical environmental characteristics would differ between the upper and lower extents of the annually flooded riparian zone on the John Day River, and that relationships between species and environmental variables would display differences between these two zones. Vegetation, environmental variables, and relationships between them were assessed for the entire annually flooded riparian zone, and for the proposed upper and lower zones. Data were collected from 60 one-square-meter quadrats: 30 in each the upper and lower zones. Sites were randomly selected and located so that flood duration was roughly equal at all sites within each zone. 34 plant species were encountered: 25 in the upper zone, 27 in the lower zone. Wetland obligate and facultative wetland species groups and eight individual species accounted for statistically different percentages ofquadrat cover between zones. ANOSIM analysis identified two statistically distinct vegetation communities between the two zones. Soil texture averaged 75.85% sand and 20.81% fines. Sand ranged between 36.69% and 95.55%. Fines ranged between 2.54% and 58.84%. A horizon depths and fine soil particle concentrations were greater in the upper zone. Coarser soils with more sand and gravel dominated the lower zone. All enviromnental variables studied, except pH, were highly variable throughout the study area. ANOSIM analysis results suggest that the upper and lower zones have distinct, statistically different physical environments from each other. Regression analyses relating species quadrat cover to physical environmental variables were performed for the total, upper, and lower riparian zones. Numerous differences were identified between the upper and lower riparian zones that the riparian scale analyses did not represent accurately. There were ten instances in which the zone scale analyses identified a relationship in either the upper or lower zone, while the corresponding riparian scale analysis failed to identify any relationship. The results of this study indicate that vegetation and the physical environment are statistically different between the upper and lower zones on this river, and that relationships between a given plant species and environmental variable can vary between zones. Future research and management efforts should consider and address the potential for such between-zone variation.
345

L'accès du public aux terrains privés pour la randonnée pédestre au Québec : quelle compatibilité avec l'exercice des droits de propriété?

Tanguay, Caroline 07 1900 (has links)
Ce mémoire s’intéresse à la collaboration entre deux groupes d’acteurs grâce à qui des sentiers de marche en milieu naturel sont rendus accessibles au public sur les terres privées : les propriétaires fonciers et les gestionnaires de réseaux pédestres. Souvent fondé sur des ententes de droit de passage, leur partenariat répond à une demande sociale grandissante pour la pratique d’activités de sport et de loisir en plein air, plus forte encore à proximité des zones urbaines. Or, il repose sur des assises précaires. Compte tenu du peu de connaissances dont nous disposons sur ces enjeux au Québec, cette recherche exploratoire vise à comprendre dans quelle mesure l’accès du public aux sentiers de randonnée pédestre formels localisés sur des terrains privés peut être compatible avec l'exercice des droits de propriété privés. Nous cernons à la fois les facteurs influençant cette compatibilité ainsi que les stratégies mobilisées par les gestionnaires et les propriétaires pour utiliser ces facteurs comme leviers ou, au contraire, réduire leur portée. Une enquête de terrain qualitative a été menée en deux phases : d’abord auprès de gestionnaires de sentiers de plusieurs régions du Québec (première phase), puis auprès de gestionnaires et de propriétaires fonciers de Sainte-Brigitte-de-Laval (cas ciblé pour la seconde phase). Les résultats de la recherche montrent que l’accès du public peut être compatible avec l’exercice des droits de propriété privés, mais que cela dépend de deux facteurs majeurs : la capacité des acteurs (1) d’actualiser leurs propres pratiques et représentations du terrain et (2) de se faire mutuellement confiance. Les manifestations de ces facteurs et les stratégies employées par les deux groupes d’acteurs sont exposées. Puis, nous identifions l’enjeu cardinal pour chacun d’eux. Les propriétaires souhaitent continuer de profiter de leur propriété en dépit et au-delà de la présence du sentier. Les gestionnaires, conscients du caractère asymétrique de la relation qui les lie aux propriétaires, tentent de construire le lien de confiance avec ces derniers, tout en composant avec des ressources limitées. Le mémoire propose finalement une réflexion sur de possibles pistes d’intervention à partir des solutions évoquées par les participants et d’un examen de différents outils d’urbanisme. La recherche expose sa contribution sur les plans théorique, méthodologique et pratique. Elle a été l’occasion de revisiter l’étendue et les limites de l’exercice des droits de propriété au Québec en plus de montrer la valeur heuristique de la théorie de l’accès. Sa démarche exploratoire, itérative et les méthodes utilisées ont permis de générer de nouvelles connaissances empirique pour le Québec. La réflexion sur de possibles pistes d’intervention pourra éclairer les professionnels de l’aménagement du territoire. / This paper focuses on the collaboration between two groups of actors who make nature trails accessible to the public on private land: landowners and hiking trails managers. Often based on right of way agreements, their partnership meets a growing social demand for outdoor recreation, which is even stronger near urban areas. However, it is based on a precarious foundation. Given the limited knowledge we have on these issues in Quebec, this exploratory research aims to understand the extent to which public access to formal hiking trails located on private land can be compatible with the exercise of private property rights. We identify both the factors influencing this compatibility and the strategies mobilized by managers and owners to use these factors as levers or, on the contrary, to reduce their scope. A qualitative field survey was conducted in two phases: first with hiking trail managers located in several regions of Quebec (first phase), and then with managers and private landowners in Sainte-Brigitte-de-Laval (case selected for the second phase). The research results show that public access can be compatible with the exercise of private property rights when associated with two major factors: the actors’ ability (1) to accomplish their own uses and representations of the land and (2) to trust each other. The manifestations of these factors and the strategies employed by the two groups of actors are outlined. Then, we identify the main issue for each of them. The private landowners want to keep on benefitting from the property despite and beyond the presence of the trail. The managers – aware of the asymmetrical nature of the relationship between them and the owners – try to build trust with the latter while dealing with limited resources. Finally, a reflection on possible avenues of intervention is initiated based on the solutions mentioned by the participants and an examination of various urban planning tools. The research presents its contribution on the theoretical, methodological, and practical levels. It was an opportunity to revisit the scope and limits of the exercise of property rights in Quebec and to demonstrate the heuristic value of access theory. Its exploratory, iterative approach, and the methods used have generated new empirical knowledge for Quebec. The reflection on possible avenues of intervention could enlighten land use planning professionals.
346

Behavior and Habitat Use of Roseate Terns (Sterna dougallii) Before and After Construction of an Erosion Control Revetment

Grinnell, Corey 01 January 2010 (has links) (PDF)
An erosion control revetment was constructed at the Falkner Island Unit of the Stewart B. McKinney National Wildlife Refuge, Connecticut during the winter of 2000–2001. At the time, Falkner Island was the fifth largest breeding colony site for the federally endangered Roseate Tern. This study measures and describes some baseline information regarding Roseate Tern nesting, behavior, and habitat use at Falkner Island during the three breeding seasons prior to revetment construction (1998–2000). This baseline information is then compared to similar information from the first breeding season following revetment construction (2001). For Roseate Tern adults, this study examined changes in pre-nesting habitat use, nest site distributions, and pre-nesting behavioral time allocation. Changes in habitat availability and habitat use by Roseate Terns are compared as a result of the revetment construction. Roseate Terns used rocky beach in a greater proportion than other habitats before revetment construction, and used revetment boulders in a greater proportion than all other habitats after revetment construction. Roseate Terns nested more often in artificial sites (nest boxes and tires) than in natural sites in all years of the study. The mean date for the first eggs in each nest did not differ between years. We observed more Roseate Terns prospecting artificial nest sites (n = 66 times) than natural sites (n = 21 times) for three years of this study. Prospecting behavior occurred later in the season in some subcolonies, but this difference did not appear to be related to the construction. For Roseate Tern chicks, this study investigated the use of crevices as hiding places from before (1999–2000) and after (2001) the construction of an erosion control revetment. In all years, Roseate Tern chicks used crevices found under artificial nest sites more frequently than expected by chance when compared to crevices found in other microhabitats. Chicks also used crevices formed in various microhabitat types at different stages of development. The erosion control revetment created crevices that had larger openings, steeper floors, and deeper lengths than those previously used by chicks before construction. In the year after revetment construction, the openings of crevices used by chicks that died were wider than crevices used by chicks that survived. We discuss our findings in the context of the potential consequences that the revetment construction had on Roseate Tern chick survival.
347

An Ecosystem Approach to the Sustainability of Urbanizing Watersheds

Raposa, Sarah L 01 January 2011 (has links) (PDF)
Political boundaries make watershed planning difficult despite the influence of many state and federal programs. Broad, top-down, watershed initiatives fail to reach many municipalities due to human resources, time and legalities. Thus, a watershed ecosystem based approach to city planning should be utilized in order to integrate a holistic and scientific foundation for land use decisions. However, there is a need for research for developing and applying a watershed approach to urbanizing watersheds. The goal of this study is to provide a series of science based transferable recommendations upon which municipalities can make land use planning decisions. These recommendations are informed by a watershed modeling and prioritization study conducted with the community of Northampton, Massachusetts. Analyses of water resource planning options were made concerning future development scenarios using an approach which links water quality and quantity, land use and government. A required component of the ecosystem approach, stakeholder participation, applied the Deliberative Attribute Prioritization Procedure (DAPP) for the first time in this context to assess the relative of different environmental concerns. The results of these stakeholder focus groups showed the importance of several key attributes including land use, water quality, water quantity, and impacts to neighborhing communities that were utilized in the watershed models. This thesis provides an integrated tool for water resource planning at the municipal level. However, without the effective transfer of these recommendations into existing policies like zoning, the results of the study have limited use. Therefore implementation of recommendations within municipal planning documents is an important component. This information will be utilized to evaluate priority water resource protection overlays by providing quantitative information and decision making within a community. A citywide watershed model and analysis used to guide policy-making and decision-making will assist in fulfilling the community of Northampton’s continuing commitment to work toward economic, environmental, and equitable sustainability, as well as provide a model for other communities.
348

Impact of climate oscillations/indices on hydrological variables in the Mississippi River Valley Alluvial Aquifer.

Raju, Meena 13 May 2022 (has links) (PDF)
The Mississippi River Valley Alluvial Aquifer (MRVAA) is one of the most productive agricultural regions in the United States. The main objectives of this research are to identify long term trends and change points in hydrological variables (streamflow and rainfall), to assess the relationship between hydrological variables, and to evaluate the influence of global climate indices on hydrological variables. Non-parametric tests, MMK and Pettitt’s tests were used to analyze trend and change points. PCC and Streamflow elasticity analysis were used to analyze the relationship between streamflow and rainfall and the sensitivity of streamflow to rainfall changes. PCC and MLR analysis were used to evaluate the relationship between climate indices and hydrological variables and the combined effect of climate indices with hydrological variables. The results of the trend analysis indicated spatial variability within the aquifer, increase in streamflow and rainfall in the Northern region of the aquifer, while a decrease was observed in the southern region of the aquifer. Change point analysis of annual maximum, annual mean streamflow and annual precipitation revealed that statistically decreasing shifts occurred in 2001, 1998 and 1995, respectively. Results of PCC analysis indicated that streamflow and rainfall has a strong positive relationship between them with PCC values more than 0.6 in most of the locations within the basin. Results of the streamflow elasticity for the locations ranged from 0.987 to 2.33 for the various locations in the basin. Results of the PCC analysis for monthly maximum and mean streamflow showed significant maximum positive correlation coefficient for Nino 3.4. Monthly maximum rainfall showed a maximum significant positive correlation coefficient for PNA and Nino3.4 and the monthly mean rainfall showed a maximum significant positive correlation coefficient of 0.18 for Nino3.4. Results of the MLR analysis showed a maximum significant positive correlation coefficient of 0.31 for monthly maximum and mean streamflow of 0.21 and 0.23 for monthly maximum and mean rainfall, respectively. Overall, results from this research will help in understanding the impacts of global climate indices on rainfall and subsequently on streamflow discharge, so as to mitigate and manage water resource availability in the MRVAA underlying the LMRB.
349

Using an Inventory of Unstable Slopes to Prioritize Probabilistic Rockfall Modeling and Acid Base Accounting in Great Smoky Mountains National Park

O'Shea, Thomas A 01 August 2021 (has links)
An inventory of unstable slopes along transportation corridors and performance modeling are important components of geotechnical asset management in Great Smoky Mountains National Park (GRSM). Hazards and risk were assessed for 285 unstable slopes along 151 miles of roadway. A multi-criteria model was created to select fourteen sites for two-dimensional probabilistic rockfall simulations and Acid Base Accounting (ABA) tests. Simulations indicate that rock material would likely enter the roadway at all fourteen sites. ABA test results indicate that influence of significant acid-producing potential is generally confined to slaty rocks of the Anakeesta Formation and graphitic schist of the Wehutty Formation. The research illustrates an approach for prioritizing areas for site-specific investigations towards the goal of improving safety in GRSM. These results can help park officials develop mitigation strategies for rockfall, using strategies such as widening ditches and encapsulating acidic rockfall material.
350

Mortality Assessment of Redwood and Mixed Conifer Forest Types in Santa Cruz County Following Wildfire

Auten, Steve R 01 December 2012 (has links) (PDF)
On August 12, 2009, the Lockheed Fire ignited the west slope of the Santa Cruz Mountains burning approximately 7,819 acres. Foresters and other land managers were left with challenging decisions on how to evaluate tree mortality. Big Creek Lumber Company, California Polytechnic State University, San Luis Obispo (Cal Poly)’s Swanton Pacific Ranch (SPR), and other resource professionals familiar with this region teamed up to develop a method for evaluating damage and thereby mortality for redwood, California nutmeg, live oak, tanoak, California bay, Pacific madrone, big leaf maple, Douglas-fir, Monterey pine, and knobcone pine. Quantitative damage criteria were used to design three Mortality Assessment models (MA), divided into three diameter at breast height classes (1-8.9, 9-16.9, >17 inches), for all tree species. These models were compared against pre-fire data from 82, one-fifth acre fixed plots from SPR’s Continuous Forest Inventory. Since the initial evaluation using the new MA in Fall 2009, each of the 2,877 trees were re-evaluated in Spring 2010 and Spring 2011 to determine if initial evaluations from the MA in 2009 were correct. To date, predictions to determine individual tree mortality using the Mortality Assessment models have been 89.3% correct.

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