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The Bahamas Biocomplexity Study Photo CollectionStoffle, Richard W., Van Vlack, Kathleen A., O’Meara, Nathaniel B., Martinez, Aja Y. 01 August 2013 (has links)
These photographs offer illustrations of the people, places and resources in the six communities visited during the Bahamas Biocomplexity project.
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Origin and Geochemistry of Modern Bahamian OoidsDuguid, SARAH 27 January 2009 (has links)
The Bahamian Archipelago is one of the few locations in the world where ooid formation is actively occurring. Ooid cortices from six locations in the region were incrementally dissolved and analyzed for 14C, δ18O, δ13C, Mg/Ca and Sr/Ca ratios. Ooids were examined under SEM after each step in the incremental analyses to characterize the nature of dissolution. Radiocarbon dating indicates that surface ooids began forming across the Archipelago between 1000 and 2800 yr BP and continue to form today.
The ooids have the same pattern of microboring alteration across the region. The surface and outer cortex of the ooids are punctuated with unfilled microborings, whereas the inner cortex contains two morphologies of aragonite cement filling the microborings. The two morphologies of cement form in association with two different species of cyanobacteria, one is Solentia sp. the other is interpreted to be Hyella sp..
The chemistry of ooids from across the region is remarkably similar. δ18O and δ13C values for all samples vary directly, having a slope of approximately 1. The outer cortex has low δ18O and δ13C values of -3.4‰ and 0.2‰ respectively, whereas the δ18O and δ13C values of the inner cortex are high with values of 1.9‰ and 6.8‰ respectively. The presence of aragonite cement in microborings in the inner cortex increases the overall isotopic composition of both oxygen and carbon in the ooid, causing it to appear close to equilibrium with seawater. The isotopic variation in δ18O and δ13C within the cortex can be characterized as a mixing line between the low values in the unaltered ooid laminae and the aragonite cement in the microborings.
The most exterior portion of the ooid has very high Mg/Ca values and is interpreted as an amorphous calcium carbonate (ACC) coating. There are two other phases in the cortex, both being aragonite. The outer cortex has a higher Mg/Ca ratio and lower Sr/Ca ratio than the inner cortex. This difference in chemistry is a result of the presence of aragonite cement in the inner cortex.
Stable isotopic and trace element results coupled with SEM investigations indicate that microbes do not play a role in ooid formation, but instead alter the texture and chemistry of ooids after they have formed. This alteration occurs throughout the entire shoal region. A new model of ooid formation is proposed whereby a veneer of ACC precipitates on an ooid while it is at the sediment-water interface (the active phase). This veneer of ACC later recrystallizes to aragonite needles, possibly nucleating on organic material and a new cortex layer is formed. Observations from this study lead to a deeper understanding of the chemical processes involved in ooid genesis, which allows for a better understanding of paleoenvironments hosting ooid formation. / Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2009-01-27 13:29:42.765
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Hollywood films, reflective practice, and social change in teacher education : a Bahamian illustrationButler, Faith J. January 2000 (has links)
This qualitative inquiry explores the use of Hollywood films depicting teachers (teacher-films) as an approach to reflective practice and social change with 60 undergraduate students in a teacher education programme in the Bahamas. In order to facilitate critical reflection on the preservice teachers' perceptions of teaching, on themselves as teachers, and on their teaching experience, a module comprised of five teacher-films (To Sir With Love, Blackboard Jungle, Stand and Deliver, The Prime of Miss Jean Brodie, and SARAFINA!) is designed and employed. The depictions of teaching are deconstructed as a means of introducing the complexity of teaching as well as unveiling the relevance of issues such as class, race, gender, and the politics of power and position to the life of a teacher. Central to the study is exploring how prospective teachers "read" these films and what insights prospective teachers gain from the films. / The study generates four main data sources: (1) transcriptions of audio-taped group discussions with the preservice teachers, (2) the preservice teachers' written responses to questionnaires relating to the teacher-films, (3) reflective journals kept by the preservice teachers, and (4) the preservice teachers' written responses to the entire teacher-film module. The analysis of the data is presented in two parts. First, the preservice teachers' overall response to the teacher-film module is detailed. Next, their close reading of teaching and learning as portrayed in two of the films, The Prime of Miss Jean Brodie and SARAFINA!, is discussed. A number of themes that emerge within the data such as the role, influence, and power of teachers are explored. / This inquiry has revealed how teacher-films can be utilized within teacher education to prompt neophyte teachers to examine their identity as teachers, to scrutinize their perceptions and assumptions, as well as to stimulate questions with regard to the perplexities of teaching. Film pedagogy also has potential to heighten awareness of vital issues of teaching such as race, class, and gender, to provoke self-study, and prompt social change. In addition, educators and researchers can learn much by examining preservice teachers' responses to popular screen images of teachers as well as other popular culture images of teachers. This information can be used to design teacher education curricula that more adequately prepare neophyte teachers for the challenges of teaching.
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Coastal landforms of Cat Island, Bahamas a study of Holocene accretionary topography and sea-level change /Lind, Aulis O. January 1968 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1968. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
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Incorporation and Preservation of Molybdenum and Uranium Isotope Variations in Modern Marine SedimentsJanuary 2012 (has links)
abstract: Molybdenum and uranium isotope variations are potentially powerful tools for reconstructing the paleoredox history of seawater. Reliable application and interpretation of these proxies requires not only detailed knowledge about the fractionation factors that control the distribution of molybdenum and uranium isotopes in the marine system, but also a thorough understanding of the diagenetic processes that may affect molybdenum and uranium isotopes entering the rock record. Using samples from the Black Sea water column, the first water column profile of 238U/235U variations from a modern euxinic basin has been measured. This profile allows the direct determination of the 238U/235U fractionation factor in a euxinic marine setting. More importantly however, these data demonstrate the extent of Rayleigh fractionation of U isotopes that can occur in euxinic restricted basins. Because of this effect, the offset of 238U/235U between global average seawater and coeval black shales deposited in restricted basins is expected to depend on the degree of local uranium drawdown from the water column, potentially complicating the interpretation 238U/235U paleorecords. As an alternative to the black shales typically used for paleoredox reconstructions, molybdenum and uranium isotope variations in bulk carbonate sediments from the Bahamas are examined. The focus of this work was to determine what processes, if any, fractionate molybdenum and uranium isotopes during incorporation into bulk carbonate sediments and their subsequent diagenesis. The results demonstrate that authigenic accumulation of molybdenum and uranium from anoxic and sulfidic pore waters is a dominant process controlling the concentration and isotopic composition of these sediments during early diagenesis. Examination of ODP drill core samples from the Bahamas reveals similar behavior for sediments during the first ~780ka of burial, but provides important examples where isolated cores and samples occasionally demonstrate additional fractionation, the cause of which remains poorly understood. / Dissertation/Thesis / Ph.D. Geological Sciences 2012
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Water Resources Assessment and Geographic Information System (GIS)-based Stormwater Runoff Estimates for Artificial Recharge of Freshwater Aquifers in New Providence, BahamasDiamond, Mildred Genevieve 31 March 2011 (has links)
The Bahamas is a small island nation that is dealing with the problem of freshwater shortage. All of the country’s freshwater is contained in shallow lens aquifers that are recharged solely by rainfall. The country has been struggling to meet the water demands by employing a combination of over-pumping of aquifers, transport of water by barge between islands, and desalination of sea water. In recent decades, new development on New Providence, where the capital city of Nassau is located, has created a large area of impervious surfaces and thereby a substantial amount of runoff with the result that several of the aquifers are not being recharged. A geodatabase was assembled to assess and estimate the quantity of runoff from these impervious surfaces and potential recharge locations were identified using a combination of Geographic Information Systems (GIS) and remote sensing. This study showed that runoff from impervious surfaces in New Providence represents a large freshwater resource that could potentially be used to recharge the lens aquifers on New Providence.
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Need for government assistance in housingDavis, Ivern Ulysses January 1968 (has links)
Housing is one of the major problems in North America This problem becomes more acute daily in the urban centers as (1) the population explosion continues; (2) the process of urbanization increases; and (3) new household units are formed in greater numbers. Although in the United States and Canada there is no street sleeping and squatting as there is in India and other countries of Asia and South America, nevertheless, the inadequate conditions of housing of the slums and blighted areas result partially from the pressure for shelter caused by these three demographical factors.
The problem of housing is essentially a problem of enabling every citizen to obtain decent accommodation at a price that he can afford. In addition to the demographic factors already mentioned, other dimensions of complexity of this problem are contributed by the fact that housing deficiencies
correlate closely with low income levels, inferior employment
and educational opportunities, and frequently, racial discrimination. This problem is further compounded by the increasing cost of housing construction.
The search for further solutions to alleviate the housing problem, and the realization of the inter-relationship of housing standards, housing costs, and income led to the study hypothesis:
That there is a certain family income level below which adequate housing cannot be obtained without assistance.
A technological break-through in the housing industry can ease considerably the present housing problem. Of all man's necessities, however, housing has seen the fewest production
changes in recent centuries. Until such breakthrough is achieved the existing resources must be used to combat the problem.
Since the "New Deal" of the 1930's both the governments
of Canada and the United States have actively participated in housing assistance and support programs. These programs, however, have not assisted the low income groups as much as the middle and upper income groups. Of over 73,000 FHA applications in 1967 only 5,000 were for a variety of social purposes which included low-income housing. The housing codes, urban renewal programs, and public housing projects have not yet sufficed to provide every North American family with a home of adequate standards.
Governor Otto Kerner of Illinois, head of the Commission on a Civil Disorder, regards poor housing as one of the major causes of the social problems now facing almost every American city. A recent HUD study forecasts a need, greatest among the urban poor, for 22.5 million units of new housing in the next decade. The question is, how can this need be met?
This study essentially reviews some of the methods by
which government can assist low income families and households in obtaining adequate housing. The review begins with an examination of the nature of the housing problems in which the inter-relationship of housing standards, housing costs, and family incomes are analysed and evaluated. The conclusions from the review were; (1) that the costs of housing increase with the level of standard, and (2) that family income was the primary obstacle to adequate housing.
The significant findings have been that a wider choice of methods of housing assistance can be adopted, as well as a wider choice of type and tenure of accommodations. Such range of choice can alleviate many of the present problems in urban renewal and relocation programs and most of all reduce the need for substandard dwelling units.
In view of these findings and recognizing that adequate housing is in the interest of the family, the community, and the nation, the thesis investigates some of the ways by which the amount and method of assistance required by the low income groups may be determined if they are to be housed adequately.
By means of the case study method the hypothesis was
tested and verified. The most significant conclusion drawn from
the case study is the substantiation of the validity of the
hypothesis:
That there is a certain family income level
below which adequate housing cannot be obtained without assistance.
This income level is established by the cost of minimum standard of socially and officially accepted housing. The measurement of this income level is therefore dependent on two factors: (1) determining what is the minimum housing standard for a family, with due regards to family size, and existing social, cultural, and official attitudes; and (2) determining what is the minimum cost of such standard of housing, with due regards to existing construction methodology and practices, technological skills, and available materials. / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate
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Acoustic Telemetry Studies of Bonefish (Albula vulpes) Movement Around Andros Island, Bahamas: Implications for Species ManagementHaley, Vanessa 03 November 2009 (has links)
Bonefish (Albula spp.) support an economically important catch-and-release recreational fishery, as well as artisanal harvesting, in The Bahamas. Little is known about the large-scale movement patterns of bonefish, yet such information is essential for proper species conservation and management. I used acoustic telemetry to determine large-scale movement patterns of bonefish around Andros, Bahamas, in conjunction with presumed spawning migrations. I conclude that bonefish travel long distances from shallow flats to pre-spawning aggregation sites in proximity to off-shore reef locations. Off-shore movement to deeper reef locations occurs around both new and full moons. This study has also confirmed anecdotal reports that the North Bight is an important spawning migration corridor for bonefish. This information is critical for the protection of bonefish and identifies important habitats (e.g. migration corridors and pre-spawning aggregations) on Andros that warrant protection from coastal degradation or fishing pressures.
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REESTABLISHMENT OF A QUEEN CONCH, LOBATUS GIGAS, BREEDING POPULATION IN A MARINE PROTECTED AREA IN THE BAHAMASUnknown Date (has links)
The queen conch, Lobatus gigas, is key to the Bahamian way of life. Recent studies suggest that commercial stocks will be depleted in The Bahamas in 10-15 years. In response to this, an egg farm was established in a historic breeding ground in Moriah Harbour Cay National Park, Exuma, Bahamas. Previously used for aquaculture, the egg farm concept was tested as a restoration method. Conch were tagged (n=251) and stocked in a 1,385 m2 (0.14 ha) circular enclosure at an equivalent density of 1,813/ha or 1 conch/5.5 m2. The egg farm was visited every 24-48 hours during the study period (May 26-August 14, 2019) to examine conch distribution, burial, predation, breeding, and egg mass laying. Queen conch Essential Fish Habitat was characterized in this study, contributing to a knowledge gap concerning conch spawning areas. No egg masses were laid, despite temperature, sediment solid-phase organics, calcium carbonate, and other seagrass habitat characteristics displaying similarities to previous studies in which conch spawned. It is speculated that egg laying did not occur due to handling disturbances, which may have caused the conch to resorb their gonads. Comprehensive recommendations are made for future egg farms intended for restoration. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection
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Bahamian Quaternary Geology and the Global Carbon BudgetLarson, Erik Bond 17 May 2014 (has links)
Sea-level change during the Quaternary has had significant impacts on the geology of the Bahamas and the global carbon budget. During periods of low sea-level position conduit caves form in the Bahamas as a function of their respective water budgets. These conduit caves can then collapse and if this collapse reaches the surface a progradational collapse blue hole can be made. Upon subsequent sea-level rise these blue holes can become sediment inilled. Tidal pumping through these sedimentilled blue holes can result in the formation of whitings. Whitings are formed when the tidally pushed water warms and degasses CO2, driving the precipitation of CaCO3. Whitings are also formed on the shallow banks by resuspension by fish. As sea-level fluctuates the amount of land in the Bahamas and other carbonate regions increases or decreases with sea-level fall or rise, respectively. As the amount of land increases in the Bahamas and other carbonate regions, there is a decrease of carbonate rock exposure at high latitudes due to glaciation. The loss of high latitude carbonates is made up for in the gain of low latitude carbonates in terms of rates of inorganic carbon drawdown associated with karst processes. Additionally, this inorganic carbon draw down from karst processes represents approximately 16% of the unknown carbon sink as reported by the IPCC. This study is significant in that it contributes to the understanding of sea-level fluctuations in relation to the geology of the Bahamas and the global carbon budget.
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