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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.
241

Mycobionts, germination, and conservation genetics of federally threatened Platanthera praeclara (Orchidaceae) /

Sharma, Jyotsna, January 2002 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.
242

Mycobionts, germination, and conservation genetics of federally threatened Platanthera praeclara (Orchidaceae)

Sharma, Jyotsna, January 2002 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.
243

A habitat suitability model for Ricord's iguana in the Dominican Republic

Dine, James. January 2009 (has links)
Thesis (M.S.)--Indiana University, 2009. / Title from screen (viewed on August 27, 2009). Department of Geography, Indiana University-Purdue University Indianapolis (IUPUI). Advisor(s): Jan Ramer, Aniruddha Banergee, Jeffery Wilson. Includes vita. Includes bibliographical references (leaves 47-52).
244

Effects of temperature, photoperiod, and substrate on the maturation and reproductive behavior of the Topeka shiner (Notropis topeka)

Witte, Christopher C. Noltie, Douglas B. January 2008 (has links)
The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on October 6, 2009). Thesis advisor: Dr. Douglas B. Noltie. Includes bibliographical references.
245

Spatial analysis of Helianthus schweinitzii (Schweinitz's sunflower), an endangered species endemic to the Piedmont of North Carolina

Smith, Tammy Capps. January 1900 (has links)
Thesis (M.A.)--The University of North Carolina at Greensboro, 2008. / Directed by Roy Stine; submitted to the Dept. of Geography. Title from PDF t.p. (viewed Apr. 13, 2010). Includes bibliographical references (p. 58-64).
246

The diversity and endangerment of Hawaiian dry forests and their role as a signal for climate change

Pau, Stephanie, January 1900 (has links)
Thesis (Ph. D.)--UCLA, 2009. / Vita. Includes bibliographical references.
247

Animales..¿En peligro de extinción o en peligro de que los extingamos?

Rodríguez García, Gustavo 12 August 2014 (has links)
This paper presents the issue of endangered species from a Law & Economic's perspective. In this way, instead of defending the creation of legal mechanisms oriented to public protection of animals (seen as a heritage of humanity), the author maintains the reasons why animals should be considered under a private property regime that provides incentives for their care and for productivity. / Revisión por pares
248

SCAPHIRHYNCHUS STURGEON EARLY-LIFE HISTORY

Phelps, Quinton Edward 01 August 2011 (has links)
Rehabilitation of sturgeon populations requires an understanding of sturgeon autecology during all life stages, especially during early life when high mortality occurs. To begin to understand sturgeon early-life history I determined river of origin on a multi-basin scale (i.e., potential rivers of origin). I then determined habitat needs and early life demographics on a more localized scale (i.e., specific river). Trace elements differ between river reaches of the central US and may be used to determine origin of age-0 sturgeon. My trace element analyses suggested that age-0 sturgeon captured in the Middle Mississippi River, which extends from the confluence of the Missouri River downstream to the confluence of the Ohio River, drifted from as far upstream as the Gavins Point Dam on the Missouri River (> 1200 km), while other individuals originated locally in the Middle Mississippi River. On a more refined scale of habitats, I used trawling to identify habitat features used. Age-0 Scaphirhynchus sturgeon catch rates were highest around artificial structures (i.e., wing dikes) and island areas while main channel habitat comprised the lowest catch rates. Within these habitats, young sturgeon frequently occupied low velocities (i.e., ~0.1), moderate depths (i.e., 2 to 5 m), and sand substrate. Although determination of river of origin and specific habitats used are imperative for restoration, sturgeon populations are likely regulated by factors within habitats that affect early-life dynamics. Mean sturgeon growth rates ranged from 1.42-1.50 mm/d over the four years but did not differ among years. Individuals hatched over a 25 to 50-d period and peak hatch dates were between 10- 20 May during all years. Hatching coincided with optimum spawning temperatures of 17-20oC and a rise in river stage. Abundance was positively related to river stage, with longer durations of high water related increasing abundance. Mortality of age-0 sturgeon increased with the number of days where water temperature exceeded 28 oC. In the end this study has set benchmarks for understanding factors affecting the early-life ecology of Scaphirhynchus sturgeon.
249

Developing an environmental education strategy framework: a case study of the Endangered Wildlife Trust (EWT)

O'Grady, Janis January 2005 (has links)
The study focused on the development of an environmental education (EE) strategy framework in the Endangered Wildlife Trust (EWT) of South Africa. Evidence shows that the roles of conservation and biodiversity education could potentially be merged towards producing a practical strategy, beneficial to the organisation and its individual staff members. Questionnaires, interviews and the individual perceptions of staff members, as well as the analysis of relevant documents, suggested that the potential for the practice of EE towards the development of an EE strategy within the organisation is substantial. EWT staff members can contribute towards a change in the way that South Africans think about conservation and nature. Environmental ethics need to be promoted and understood by all. Within the EWT, environmental education activities are in place and diverse, yet they lack any form of monitoring and evaluation. The Trust is already practicing a form of EE but the potential to do more and the opportunities for expansion are unlimited.
250

STATUS AND DISTRIBUTION OF THE STATE-THREATENED MARSH RICE RAT (ORYZOMYS PALUSTRIS) IN ILLINOIS

Eubanks, Bryan Wayne 01 May 2010 (has links)
The marsh rice rat (Oryzomys palustris) is a semi-aquatic rodent classified as state-threatened in Illinois due to historical wetland loss coupled with being on the northern periphery of its range. The most recent survey for this species in Illinois occurred in 1988, and this study reassessed its status and distribution. From 2007 to 2009, I used live traps to sample for rice rats at previously occupied and random wetland-dominated sites in 5 southern Illinois watersheds. I captured 132 individual rice rats 192 times in 13,248 trap nights. Capture success was 15.10 captures/1,000 trap nights. I detected rice rats within 3 of 5 watersheds, 16 of 48 sites, and 5 new locations. Most rice rats were captured in permanent or semi-permanent emergent wetlands and rice rat occurrence was strongly related with coal mine-associated wetlands. I collected microhabitat measurements at 10% of trap locations and recorded landcover types within and around sites. I analyzed data using t-tests, logistic regression, and occupancy modeling. Percent herbaceous cover and percent visual obstruction (0.0-0.5m) positively influenced rice rat occurrence and were among the most important microhabitat models. The best model in the candidate set of landcover variables included proportion of upland grass in areas surrounding wetlands as a predictor of rice rat occurrence. I believe insufficient evidence exists to warrant removal of the threatened status of the marsh rice rat. However, current management practices, such as wetland restoration, grassland restoration, and mowing of roadside ditches, likely benefit rice rat populations. Slight modification of these management activities may facilitate the eventual delisting of marsh rice rats.

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