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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.
231

Actitudes hacia la lengua náhuatl : Un estudio sociolingüístico con jóvenes de la Ciudad deMéxico.

Jonsson, Josefina January 2014 (has links)
Nahuatl is one of the indigenous languages in Mexico that is at risk of falling out of use. The research in the last years have showed that this occurs due to the low amount of Nahuatl speakers and the social stigma and discrimination towards the indigenous peoples, among other factors.The studies of language attitudes are relevant when making attempts to revitalize a language. As Mexico City authorities have considered to implement a revitalization project, we wanted to approach the real situation of Nahuatl in that city. Our purpose was to measure the attitudes of young people towards this language. By using a direct method –a questionnaire- we asked two groups of students if they agreed or disagreed with some items about Nahuatl and its speakers. One group had contact with Nahuatl speakers and but not the other one. We compared the results and they showed that the students who have contact with Nahuatl have more positive attitudes than those who don’t have any contact with it. This study also revealed that the reason why the first group showed positive attitudes was solidarity with the Nahuatl speakers. However, the both groups considered that speaking or learning Nahuatl cannot contribute to raise their status in the Mexican society.
232

A Geographic Information Systems Tool Development For Geostatistical Analysis Of Endangered Endemic Vascular Plants Of Turkey

Demirci, Barbaros 01 June 2005 (has links) (PDF)
Modern information systems strive to provide effective use of resources. Supplied with analysis tools, geographical information systems (GIS) can serve its stakeholders with minimal requirements. In this study, GIS capabilities were employed for Turkish Flora. Data related with the threatened plants that are indigenous to Turkey were gathered from the relevant literature and reshaped into a dataset in which spatial locations were represented in a geographically referenced format. Afterwards, this output was used to investigate the affects of different factors on the distribution patterns of these plants by means of functions of GIS and multivariate analysis. At last, overlay analysis was employed in order to reveal the congruence between official protection reserves, spatial locations of the plants in danger and areas of importance for other elements of wildlife specifically birds. Outcomes of the study is three-fold. First of all, a simple algorithm was established which can be used in the formation of a unified database of widely distributed floristic data in Turkey. Geographically referenced data and the analysis results produced in the study is another value added for Turkish botanics. From another perspective, effectiveness of GIS in handling different types of non-standard data were scrutinized. Overlay analysis of locations of the plants and the protection reserves constituted the managerial aspect of the study by pointing large gaps in the actual protection coverage and proposing candidate regions for official reserve choices of the future. In essence, GIS was deemed to be an effective tool for parties working on non-standard spatial data.
233

The Population Biology Of A Narrow Endemic, Centaurea Tchihatcheffii Fisch. &amp / Mey. (compositae), In Ankara, Turkey

Cakarogullari, Didem 01 September 2005 (has links) (PDF)
Centaurea tchihatcheffii Fisch. &amp / Mey. is a critically endangered annual plant species with a narrow distribution in G&ouml / lbaSi, Ankara. The aim of this study is to understand the population dynamics of the species to help find the best way to conserve species for long term viability. The two healthiest subpopulations containing more than 1.5 million individuals were studied to estimate demographic parameters i.e. survival and reproduction rates by monitoring marked individuals, to identify pollinators, dispersers and pollen &amp / seed predators and to investigate population status, natural threats and their effects. The species is considered a weed in cereal plantations, showing adaptations of ruderal habit: High population densities (~18.5-63.2 individuals/0.5 m2), persistent seed bank with many viable seeds (~20,000/m2), rapid growth matching favorable weather conditions (almost 15 weeks from rosette to flowering), high survival with premature deaths making up only 2-20% of natural deaths mostly at rosette stage, no density dependent mortality, seed production by selfing and crossing via generalist pollinators, high reproduction rates (1200-7000 seeds/m2) and promotion of growth on aerated soil whereas inhibition with herbicides. Insect and avian predators do not cause an important damage to population. Absence of mutualists aiding in pollination (honeybee) and dispersal (ants) is out of question. There is no natural limitation on population persistence. The major threats are anthropogenic, i.e. cereal cultivation, construction and collection of individuals from natural populations. Conservation of remaining subpopulations as a reserve and alternative methods in cereal cultivation like reduced or no herbicide application should be considered as high priority conservation strategies.
234

Threats to native aquatic insect biodiversity in Hawaiʻi and the Pacific, and challenges in their conservation

Englund, R. A (Ronald A.) January 2005 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 2005. / Includes bibliographical references. / Also available by subscription via World Wide Web / ix, 202 leaves, bound ill., map 29 cm
235

Movement patterns, home range and habitat selection by Kakapo (Strigops habroptilus, Gray 1845) following translocation to Pearl Island, southern New Zealand

Joyce, Leigh, n/a January 2009 (has links)
Understanding the relationship between organisms and their environment is particularly important for the conservation and management of endangered species. The kakapo (Strigops habroptilus, Gray 1845) is a critically endangered, lek breeding, flightless nocturnal parrot endemic to New Zealand. In April 1998, a total population of fifty-six kakapo was known to survive on offshore islands. Twenty-six kakapo, thirteen males and thirteen females, were temporarily transferred to Pearl Island (518 ha), southern Stewart Island, from April 1998 to April 1999. The translocation of kakapo to Pearl Island, and subsequent breeding season, provided an ideal experimental framework to study kakapo dispersal, movement patterns, home range development, habitat selection, and lek development during the non-breeding and breeding seasons. A total of 4425 radio locations were analysed for all twenty-six birds, with a mean error polygon of 0.03 ha and an estimated average radio telemetry error of 21.6 m. Various home range analysis techniques were used to estimate kakapo home range size and overlap including: minimum convex polygons (MCP), modified minimum convex polygons (MMCP), harmonic mean analysis, adaptive kernel methods and cluster analysis. Estimates of kakapo home range size differed significantly depending on the method used (ANOVA, general linear model: F₁₃, ₁₀₇₆ = 63.99, p < 0.0001) and the season (F₂, ₁₀₇₆ = 160.75, p < 0.0001). Breeding home range size was significantly larger than non-breeding range size (mean difference = 67.6 ha, t₂₅ = 15.27, p < 0.0001). Calculations from 100% MCP and 95% harmonic mean analysis resulted in larger estimates of home range size and overlap compared to other methods. Cluster and kernel analyses appeared to give the most accurate home range representation for kakapo. Core home range areas showed a greater degree of similarity between methods. Male and female mean annual home range size did not differ significantly, whereas males had significantly (p < 0.05) larger home ranges than females during the nonbreeding season. Minimum convex polygons and harmonic mean analysis suggested that there was no significant difference in the way in which males and females interacted with each other. Kernel and cluster analyses indicated that females would overlap a greater proportion of another bird�s home range than males would. Cluster analysis also indicated that a female would have more of her home range occupied by another bird than a male would. The fact that different methods produced different quantitative results is an important consideration when using home range analysis to make conservation management decisions. Researchers must determine which method is the most appropriate for a particular research objective, species, or study area. The application of geographical information systems, ERDAS image classification techniques and global positioning systems was an integral part of this study. A large-scale vegetation classification map of Pearl Island was produced in order to quantify habitat selection by kakapo. The unsupervised classification technique produced the least accurate vegetation map, with an accuracy measure of 17-23%, compared to 52% for the supervised classification. The highest accuracy was obtained using an integrated approach involving inductive classification and deductive mapping, resulting in a vegetation classification map which correctly classified 95% of vegetation samples. Thirty-seven ecotone classes were identified and a total ecotone length of approximately 124 km was detected. Resource selection ratios and resource selection functions were estimated using a combination of discrete, continuous and area-based habitat variables. Circular buffers around used and available point locations were generated to determine whether kakapo selectively use vegetation mosaics. The probability of selection increased with increasing species diversity in each 75-metre radius buffer. Kakapo selected habitat mosaics and vegetation types with higher species diversity and moderate to high abundance of mature rimu and yellow silver pine trees.
236

Establishing mating systems by microsatellite analysis in declining saltwater crocodile (Crocodylus porosus) hatchling production at Edward River Crocodile Farm (Nth. Queensland)

Jamerlan, Mona Lisa Unknown Date (has links)
No description available.
237

Prey biomass abundance, distribution, and availability to the endangered stellar sea lion (Eumetopias jubatus) population at Ugamak Island, Alaska, 1995-99

Chumbley, Kathryn. January 2007 (has links) (PDF)
Thesis (M.E.S.)--The Evergreen State College, 2007. / Title from title screen (viewed 1/24/2008). "MES thesis." Includes bibliographical references (p. 79-88).
238

Insects on wood-decaying polypores : conservation aspects /

Jonsell, Mats, January 1900 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Härtill 6 uppsatser.
239

Bryophytes, lichens and dead wood in young managed boreal forests /

Rudolphi, Jörgen, January 2007 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2007. / Härtill 4 uppsatser.
240

Grassland plant diversity in relation to historical and current land use /

Gustavsson, Eva, January 2007 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2007. / Härtill 4 uppsatser.

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