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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.
51

Miami-Dade Task Force: A Content Analysis of How Coastal Communities View Sea Level Rise as a Threat

Alvaro, Francisco 01 May 2019 (has links)
Sea level rise (SLR) has become a serious threat for coastal communities in recent years. Many communities, including South Florida, are already having the security of their daily lives impacted as climate change causes SLR and other environmental impacts to worsen. This study reviews the Miami-Dade Sea Level Rise Task Force Report to determine how this coastal county government views SLR as a threat. Using mixed content analysis to analyze the report qualitatively and quantitatively, the Task Force's recommendations are categorized based on their focus on security, infrastructure, economics, and the environment. One finds the concerns of the people to maintain their property and infrastructure, as well as their access to water and other basic needs, as insurance costs spike and funding becomes more difficult to obtain. Policies will have to be revised using updated scientific studies, modeling, and mapping to mitigate against the worse-case scenarios.
52

Interdepartmental teaching of conservation at the Ohio State University /

Hanselman, David Lee January 1963 (has links)
No description available.
53

Conservation understandings in the intermediate grades /

Graff, George Portsmouth January 1962 (has links)
No description available.
54

CONTRIBUTION TO THE MANAGEMENT OF THE CENTRAL DELTA OF NIGER RIVER IN MALI.

TRAORE, GAOUSSOU. January 1985 (has links)
During the past decade, there has been a clear recognition of the relationship between environment and development, and that it is through the process of development that environment is often negatively affected. Therefore, to minimize the destructive effect of development, planning became a necessity. However, for any management goal, there are usually several alternative ways of developing a plan. My planning process began by a general resources inventory of the Republic of Mali including soils, vegetation, surface waters, groundwaters, land use, and population. Then, based on this inventory, I chose a planning area using pre-established criteria. The area chosen was the "Inland Delta of the Niger River." The Delta, with 30,100 km², has an enormous economic potential, and livestock raising is an important component of this potential. However, four main factors are limiting the development of livestock raising in the region: Lack of an official and consistent land right, uncontrolled increase of the number of animals, uncontrolled increase of cultivated fields, and persistent drought. The objective of this dissertation was to make a preliminary investigation which would help the Government of the Republic of Mali establish a coherent and integrated plan for all economic activities in the Delta. The economic, social and environmental components of the current livestock management and two management alternatives have been analyzed, using a model planning unit and also a herd model. The first alternative consisted of changing the herd composition, and the second alternative was a combination of changing the herd composition and the use of irrigation and fertilization to grow adapted forage species. The results showed that the two alternatives are better than the current management, and that the second alternative provided the highest economic returns and stability to the region. The implementation of the proposed plan will necessitate the creation of agro-pastoral units based on soils, vegetation, and social characteristics. The Government should adopt a more coherent and coordinated policy toward the different land users of the Delta, the final objective being high stable economic returns for the population, the preservation of the basic resources, and the equilibrium among different activities.
55

Infectivity and Physiological Effects of White Spot Syndrome Virus (WSSV) in Farmed Louisiana Red Swamp Crayfish (Procambarus clarkii)

Pace, Barcley Talon 20 April 2016 (has links)
The red swamp crayfish, Procambarus clarkii, represents an important aquaculture species responsible for over half of all commercial aquaculture profits in Louisiana. White spot syndrome virus (WSSV) is highly pathogenic and induces mass mortality in crustacean aquaculture operations worldwide. Crayfish lack the adaptive ability of the vertebrate immune system, and must depend on primitive, innate immune responses to combat viral infections. This study aims to investigate the dose-response of WSSV in P. clarkii and to examine viral-host interactions by examining the biochemical and immunological changes induced by WSSV infection in this species. Viable viral particles were isolated from naturally infected P. clarkii gill tissue, quantified using a novel digital PCR approach, and inoculated into P. clarkii to determine a median lethal dose (LD50) value of WSSV particles. After estimating an LD50 value, crayfish were inoculated at this nominal concentration of viral particles, and biological tissues were sampled across time to observe physiological and immunological changes throughout the course of WSSV infection. Antioxidant activity increased over time, while immunological gene expression was downregulated in the gill tissue of WSSV-infected crayfish. Knowledge of the infectivity of WSSV in native crayfish is of critical importance to the management of the commercial aquaculture industry in Louisiana. Examination of the viral-host interactions in crayfish can be used to facilitate future investigations towards WSSV prevention and management, and serve to develop the use of P. clarkii to model innate immune responses to WSSV infection in other decapod crustaceans. This is the first study to investigate dose-response and immunological changes induced by the Louisiana strain of WSSV in native crayfish.
56

Biomass Gasification for Electricity Generation: An Integrated Approach for Development of Forest Residue-Based Projects in Rural India

Mishra, Anand 09 May 2016 (has links)
Biomass gasification is generally regarded as a promising technology for various advanced application in energy production. Biomass is the only carbon-based sustainable option among the renewable energy sources. This study is focused on fostering biomass gasification for electricity generation sector in India. The study addresses four broad aspects of biomass gasification for electricity generation - feedstock properties and gasification technology, policy and regulatory framework governing the sector, financial evaluation of electricity generation from biomass gasification, and feedstock supply. The study is divided in four chapters, each of which addresses one aspect of electricity generation through biomass gasification. Based on literature, first chapter presents a brief review of various properties of biomass feedstocks that are critical for gasification. It reviews the thermochemical conversion processes and the major issues related with biomass gasification with reference to some promising gasifier technology systems. Based on literature, second chapter examines the importance of national and sub-national policies supporting the development of bioenergy industry (including gasification for electricity generation) in various countries. The policies and instruments deployed globally are compared with those deployed in India. Third chapter posits a framework for conducting financial evaluation of a gasification power project. A case study of pine needle gasification power project in a remote rural area of Northern India is considered. In absence of historical data related with similar projects, a probability distribution for the Net Present Value (NPV) for the project is generated with the help of Monte Carlo Simulation. The simulation for NPV uses estimates of input variables from the data gathered from an existing pine needle based gasifier operating in the study area. Continuing with the case study, fourth chapter studies the villagers perspective on supplying pine needles to the gasification project. . A survey was administered to estimate villagers willingness to collect pine needles from the forests and supply it at a price to the gasification project. The willingness is modeled on demographic, livelihood, and latent factors, that are used in a Multinomial Logistic Regression Model to estimate the probability of households willingness to collect and supply pine needles to the project.
57

Vegetation Influences Microbial Community Structure and Methane Emissions in Southeastern Louisiana Wetlands

Rietl, Anthony Jason 11 May 2016 (has links)
Methane has a warming potential 28 times that of carbon dioxide and has been increasing in the Earths atmosphere since 1750. An understanding of the dynamics of methane emissions from natural sources is becoming increasingly important as we may need to mitigate emissions from these sources in the future to help reduce the effects of climate change. Wetlands are the single largest natural source of methane; however, little attention has been given to how plant species, biota, and interactions between above and belowground communities and microbial communities may affect methane emissions. First, microbial community structure and function was assessed for two salt marsh plant species, Spartina alterniflora and Juncus romerianus via bacterial, archaeal, and fungal gene fragments, and extracellular enzyme assays to determine whether wetland microbial communities were structured by vegetation, and whether communities were functionally different. Bacterial communities were differentiated by plant species in two of three sites, suggesting while vegetation likely plays a role in structuring these communities, specific site characteristics are likely of equal importance. Fungal communities were influenced more by site than vegetation, and archaeal communities appeared to be structured by vegetation. Second, four freshwater wetland plants (Sagittaria lancifolia, Panicum hemitomon, Eleocharis macrostachya, Echinochloa walteri) were transplanted and grown in large mesocosms, and clipped to differing heights under different nutrient treatments to detect changes in methane emissions, methanogen, and methanotroph communities. Methane emission rates were plant species specific, and a three way interaction indicated that species, nutrient level, and clipping level altered methane emission. Methanogen and methanotroph communities were not altered by the treatments. Lastly, densities of marsh periwinkle snails and southern ribbed mussels were manipulated inside fenced enclosures within a S. alterniflora salt marsh, and methane emissions and extracellular enzyme activities were measured over the course of a year. Southern ribbed mussels increased the emission of methane when present, but marsh periwinkle snail density had no effect. The data collected show that microbial community structure in wetlands are influenced by vegetation, that methane emission rates are plant species specific, and that southern ribbed mussels have the potential to increase methane emissions from S. alterniflora marshes.
58

Living on the Edge: An Assessment of the Habitat Use of Waterbirds in Estuarine Wetlands of Barataria Basin, LA

Patton, Brett Ashley 13 July 2016 (has links)
The wetlands of Louisiana are losing area at the rapid rate of 42.9 km2 yr-1 and the trend is expected to continue. This combined with expected sea-level rise will likely cause large shifts in vegetation and salinity regimes that will affect the wildlife species reliant on these ecosystems. Waterbirds serve as indicator species of ecosystem health in estuarine wetland habitats; therefore, these species are often the targets of wetland management goals in Louisiana. However, many proposed wetland restoration projects are focused primarily on social impacts with only a few specific waterbird species designated for management. The majority of these waterbird habitat-use studies in Louisiana wetlands have focused on waterfowl species and their abundance in wetland habitats during migration and winter. My overall objective was to compare habitat use of all waterbird taxa in fresh and saline estuarine wetland habitats. Additionally, I examined habitat use at finer spatial scales to assess a possible preference for marsh edge microhabitats when compared to open water and interior emergent vegetation. I also investigated waterbird associations with the environmental parameters of emergent and aquatic species composition, percentage of open water, and salinity. From July 2014 to December 2015, I compared waterbird density and species richness both spatially and temporally to assess habitat use. I found that species richness differed between fresh and saline habitats depending on the month, with the month of April having the greatest species richness. Waterbird density was greatest among edge microhabitat regardless of salinity type, and birds utilized this habitat up to 15 m from the edge. Density did not vary in open water plots in relation to salinity type. The relationships between environmental variables and species were significant (p=0.002) as well as relationships between guilds and environmental variables (p=0.002). These data will be useful in attempts to simulate the effects of wetland loss and salinity changes on habitat quality for waterbirds in coastal Louisiana, and will inform habitat restoration and management decisions for optimal waterbird use.
59

Relative Resistance to Breaking of Pinus taeda L. and Pinus palustris

Garms, Cory Glenn 23 June 2016 (has links)
Patterns from hurricane damage give an indication that longleaf pine (Pinus palustris) is more windfirm than loblolly pine (Pinus taeda). Tree windfirmess has been attributed to many factors including species and material properties like wood strength and stiffness. Because longleaf pine wood is stronger and stiffer than loblolly pine wood, this study used static winching methodology to see if these properties account for differences in windfirmness by measuring bending force required to break stems (MMAX). Stress-strain diagrams were constructed for pulled trees to explore how they behave under increasing loads. Based on these diagrams, it appears that living trees can act as linear elastic materials as they experience increasing static lateral stress. As expected, longleaf pine stems were stiffer than loblolly pine wood in situ based on Youngs modulus of elasticity derived from these diagrams. Tree basal area was the best predictor of MMAX for both species, however, species had no effect on the maximum bending moment required to break tree stems of a given basal area for these trees under these conditions. The stiffness of the stems was higher for longleaf than loblolly as indicated by the modulus of elasticity, but the strength of the stems as indicated by the modulus of rupture was not significantly different between the species.
60

Efficacy and Feasibility of Alginate Bait for the Louisiana Commercial Blue Crab (Callinectes sapidus) Fishery

Clowes, ElizaBeth Lorraine 05 May 2016 (has links)
Louisiana leads all U.S. states in blue crab (Callinectes sapidus) landings, but high fuel and bait costs have hindered commercial fishing productivity of Louisiana in recent years. The primary baitfish, Atlantic menhaden (Brevoortia tyrannus), has steadily increased in price and decreased in availability, while crab prices remain low. To reduce costs for fishermen, an alternative bait was developed that incorporates shrimp waste into a semi-rigid alginate matrix. Lab testing and preliminary field tests show that shrimp-alginate bait may be a suitable alternative to menhaden for Louisiana crab fishermen. I evaluated bait performance by conducting field sampling to compare catch rates and longevity of standard baitfish and shrimp-alginate bait. I performed seasonal fishery-independent testing at three sites across Southern Louisiana from summer 2014 to spring 2015, and tested the bait on commercial crabbing boats throughout coastal Louisiana during peak crab season in 2015. Catch rates of shrimp-alginate were less than menhaden overall, however, bait performance changed with site and season, and did not significantly differ when I evaluated commercially relevant crab classes. Analysis of remaining bait quantity after fishing showed that shrimp-alginate remains intact as long, or longer, than standard baitfish during peak crab fishing from June through August. After testing shrimp-alginate bait in the field, I evaluated the economic feasibility of producing the bait with a partial budget supply line. With its current formulation, shrimp-alginate can only be produced at a cost lower than menhaden (currently $0.50/lb.) under optimal production scenarios, however, slight modifications that improve shelf life could dramatically decrease the cost of bait production. Findings from both field work and feasibility analysis show promise in the alternative shrimp-alginate bait with given improvements to catch rate efficacy and product storage.

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