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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.
451

Diet Similarity of Pen-Raised Versus Native, Louisiana White-Tailed Deer in Southeastern Louisiana

Davis, Kristopher Scott 20 November 2003 (has links)
Previous studies have shown that pen-raised deer may be already predisposed to malnutrition at a higher rate then their native counterparts because they are normally raised on a pelleted ration and may not forage efficiently once released into wild habitats. Therefore, twenty pen-raised white-tailed deer that were offspring of deer obtained from Missouri (Odocoileus virginianus) were released onto a marsh pump-off habitat in southeast Louisiana (Da Bunch) to compare their diets to the diets of the native, wild, white-tail deer population already established in the area over four consecutive seasons to test this hypothesis. The microhistological analysis technique was used to estimate the botanical compositions of fecal pellets collected from both populations of deer located in the same range, over four consecutive seasons (Spring, Summer, Fall, and Winter) to account for seasonal variability. Native, wild and pen-raised deer diets averaged 78.2% similar during the year of the study, and were significantly associated to one another during each of the four seasons (P < 0.00001), indicating that all deer foraged on similar plant species in similar proportions. Differences were found in species frequencies per fecal sample, but for only five of the fifty-one species utilized significant differences were found (P < 0.001) between populations. Those species were Diodia virginiana in the spring, Aeschynomene americana, Ambrosia spp. during fall, and Berchemia scandens and Celtis laevigata in the winter. Both deer populations were predominantly grazers, with forbs constituting for a yearly average of 41.20% the deer diets. This study agrees with previous studies that concluded that translocated deer released into a new environment will adapt to the area and forage just as efficiently as the pre-existing deer population in the area assuming carrying capacity is not compromised.
452

Microstegium vimineum Spread Rate in Relation to Two Different Leaf Litter Disturbances and an Evaluation of Aboveground Biomass Accumulation and Photosynthetic Efficiency in Response to Four Light Treatments

Hull, John Andrew 01 August 2010 (has links)
Microstegium vimineum is a non-native invasive plant species classified as an annual, shade-tolerant C4 grass. There is limited research regarding variables affecting the spread of M. vimineum. Two studies were conducted to investigate the spread of M. vimineum. A field study was undertaken in 2009 to determine how M. vimineum spreads in relation to litter disturbance. In 2010, a greenhouse study was conducted to determine the impact light has on M. vimineum aboveground biomass, height growth, and photosynthetic efficiency.The field study consisted of three treatments, Undisturbed (Control), Stirring, and Removal of leaf litter, employed along the boundary of existing M. vimineum populations in ½-meter by 2-meter plots. Distance of spread from the existing population and percent cover were documented for one growing season. Plants were counted at the end of the study. Neither stirring nor removal of leaf litter had a significant impact on spread rate, percent cover, or the number of plants in a given treatment suggesting pre-growing season leaf litter disturbance does not influence M. vimineum spread, percent cover, or number of plants.The greenhouse study consisted of growing M. vimineum under four light treatments: 100, 70, 45, and 20 percent of full light. Heights were measured weekly while minimum, maximum, and variable fluorescence emission, non-photochemical and photochemical quenching, and maximum quantum yield of Photosystem II photochemistry (QYmax) were measured every 10 days. Aboveground biomass accumulation was calculated at the end of the study. Results indicate that M. viminuem aboveground biomass accumulation is highest in 70 percent to 100 percent light while photosynthetic efficiency is highest between 45 percent and 70 percent light. This research indicates that M. vimineum does not spread appreciably at low light levels (closed canopies) in areas with litter disturbances that do not change the light regime. M. vimineum has greater aboveground biomass and photosynthetic efficiencies at higher levels of light. Thus, forest disturbances that result in more light reaching the ground may influence the spread of M. vimineum by creating a more favorable environment.
453

Essential Elements of Ecological Literacy and the Pathways to Achieve It: Perspectives of Ecologists

McBride, Brooke Baldauf 05 August 2011 (has links)
<p>National assessments have led many to conclude that the level of ecological literacy among the general population in the United States is too low to enable effective social responses to current environmental challenges. However, the actual meaning of ecological literacy varies considerably between academic fields and has been a topic of intensive deliberation for several decades. Within the field of ecology in particular, a driving purpose behind this ongoing discussion has been to advance a complete, pedagogy-guiding, and broadly applicable framework for ecological literacy, allowing for the establishment of guidelines and tools for assessing educational achievement; yet, a widely accepted framework does not currently exist. What is ecological literacy and how can it be achieved? Through an extensive review of the literature, I traced the evolution of the related concepts of environmental literacy, ecological literacy, and ecoliteracy, and compared and contrasted the numerous proposed frameworks across multiple dimensions of affect, knowledge, skills, and behavior. In addition to characterizing the overall discourse, this analysis facilitated close examination of where we have been, where we are, and where we might be headed with respect to these vital conversations. To explore current perspectives on the topic, I analyzed the open-ended responses of more than 1,000 ecologists and other environmental scientists on the nature of ecological literacy and how it may be achieved. Factor analysis revealed the presence of six common dimensions underlying respondents' views of ecological literacy (cycles and webs, ecosystem services, negative human impacts, critical thinking/application, nature of ecological science, and biogeography) and five common dimensions for how to achieve it (education by mass media, formal/traditional education, financial incentive, participatory/interactive education, and communication/outreach by scientists). Based on these results, I proposed a framework for ecological literacy that, ideally, will provide guidance for the development of updated ecology curricula and assessment tools, a foundation for discussion of alignment between K-12 and higher education, and a mechanism for creating greater synergy between formal and informal learning environments. Further, to assess the impacts of innovative graduate programs designed to train ecologists in promoting ecological literacy, I analyzed pre- and post-fellowship surveys completed by participants in an ecologically focused K-12 outreach program at The University of Montana, as well as the broader impacts of a set of similar programs across the country. These highly beneficial programs are urgently needed to ensure that future leaders of the scientific enterprise are well-equipped with the tools to effectively communicate their science with diverse audiences well beyond their scientific peers. Indeed, ecologists and other natural and social scientists who study the environment have multiple roles to play in promoting a modern vision of ecological literacy in society today.</p>
454

Evaluation of industrial promoted agroforestry in Andhra Pradesh and Madhya Pradesh, India

McDonald, Brian D. January 2009 (has links)
Thesis (M.S.)--West Virginia University, 2009. / Title from document title page. Document formatted into pages; contains viii, 72 p. : ill. (some col.), col. maps. Includes abstract. Includes bibliographical references (p. 62-65).
455

Conflict expansion and containment in forestry politics /

Pralle, Sarah Beth. January 2001 (has links)
Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (leaves 346-363).
456

Le reboisement en France son utilité, sa mise en pratique ...

Bailac, Jean. January 1910 (has links)
Thèse--Faculté de droit de l'Université de Bordeaux. / "Bibliographie": p. [201]-202.
457

Contribution à l'étude de l'influence des éléments météorologiques sur l'accroissement des forêts

Primault, Bernard, January 1900 (has links)
Thèse--Zurich. / Vita. "Extrait de la Revue geofisica pura e applicata, vol. 24 (1953)." Summary in French, German and English. Bibliography: p. 55-58.
458

Die geographie des waldes in Thüringen ...

Leonhardt, Carl Otto, January 1928 (has links)
Inaug.-disc.--Jena. / Lebenslauf. "Literaturverseichnis": p. [94]-95.
459

Eräiden Suomen kaupunkien halkojen hankintaalueet markkinatieteellinen tutkimus. Summary: The firewood supply areas of Finnish towns; market research.

Holopainen, Viljo. January 1950 (has links)
Thesis--Kelsingin Yliopiston. / Place of imprint on cover: Helsinki. "Eripainos Julkaisusta, Reprint from Acta forestalia Fennica 59." Bibliography: p. [211]-219.
460

Stand dynamics and disturbance history of five oak-dominated old-growth stands in the unglaciated Appalachian Plateau

Rentch, James S. January 2001 (has links)
Thesis (Ph. D.)--West Virginia University, 2001. / Title from document title page. Document formatted into pages; contains xi, 227 p. : ill. (some col.), maps. Includes abstract. Includes bibliographical references.

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