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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.
261

Návrh zážitkové naučné stezky v přírodním parku Bohdalovsko

Chytalová, Klára January 2019 (has links)
The nature trail was designed in the diploma thesis to inform visitors about fauna, flora and historical attractions in the Bohdalovsko Nature Park. The 3.8 km route was designed in the western part of the area of interest. The nature trail was designed in 4 different variants. In the variants with interactive elements, 7 individual stops were designed. The option with QR codes on the columns and guide text was designed with 10 stops in view of better integration into the territories. In all variants, the same supporting furniture in the form of benches was designed. A bridge over the Bohdalovský potok stream was designed to make one resting place accessible. The work includes an itemized budget of the educational trail and a list of financing options including marketing proposal. Part of the thesis is an annex part containing technical report, drawing documentation and other necessary attachments.
262

Ecological Distribution and Community Analysis of Tardigrada From Choccolocco Creek, Alabama

Romano, Frank A., Barreras-Borrero, Blanca, Nelson, Diane R. 01 January 2001 (has links)
A seasonal survey of tardigrade populations in the riparian zone of the Choccolocco Creek, Alabama, was undertaken from August 1994 through December 1995. Six sites within the riparian zone were sampled in different portions of the creek. At each site, 3 trees with cryptogams were sampled six times during survey period. From a total of 108 samples, 1,588 tardigrades were extracted and individually mounted on slides in Hoyer's medium. The community was dominated (86%) by specimens in the genus Macrobiotus. One species of Echiniscus was new to science and will be described in a separate paper. No significant difference was found between tardigrade occurrence (total number of individuals) and season, moss genera, or three species. However, there was a significant relationship between the number of tardigrades and sites, indicating the need for additional replicate samples. Simpson's and Shannon-Wiener's species diversity indicated indicated that species richness and evenness were low. Jaccard's and Standard's community similarity indices suggested that the communities within the riparian zone were dissimilar along Choccolocco Creek.
263

Biodiversity Patterns on an Inshore to Offshore Gradient Using Metabarcoding and Barcoding Molecular Tools

Villalobos Vazquez de la Parra, Rodrigo 12 1900 (has links)
It has been estimated that coral reefs shelter 830 000 species. Well-studied biodiversity patterns provide tools for better representation of species in marine protected areas. A cross-shelf gradient in biodiversity exists for fishes, corals, and macroalgae. Here, an inshore to offshore gradient in biodiversity on the Saudi Arabian coast of the Red Sea was sampled using Autonomous Reef Monitoring Structures (ARMS) with barcoding and metabarcoding techniques. It was hypothesized that differences in community structure would be driven by an increase in habitat area. The difference was attributed to the greater accumulation of sediments close to shore that increases the area habitable for sediment dwelling organisms and favors macroalgal cover. Macroalgae are inhabited by a greater number of species than live coral. Only 10% of the sequences of the barcoded fraction and <1% of the metabarcoded fraction had a BLAST hit on the NCBI database with a previously identified species sequence. In addition, the rarefaction curves for all fractions did not plateau. The ARMS community composition changed from inshore to offshore and was significantly correlated with the percentage of algal and bryozoan plate cover. The differences in community composition were related to changes in habitat but not to sediments retrieved from the ARMS.
264

Relationships Between Terrestrial Vertebrate Fauna and Selected Coniferous Forest Habitat Types on the North Slope of the Uinta Mountains

Winn, David S. 01 May 1976 (has links)
The objectives were (1) to relate terrestrial vertebrate responses to the management practices used for lodgepole pine forests within the Barometer Watershed, Mountain View Ranger District, Wasatch National Forest, Utah . (2) To correlate terrestrial vertebrate densities or frequencies with community types, edge, major forest stand structures , and (3) to propose management plans to manipulate densities of major vertebrate species in a predetermined manner. The study was conducted between 1973-1975 and provides a detailed description of forest vegetation for 53 lodgepole pine (Pinus contorta) stands. For each of these stands, a complete summary is provided of tree populations, coverage, and frequency of major vascular undergrowth species . Eight lodgepole pine forest community types are defined. A key is provided for identification of each community type and its anticipated habitat type. The relationships between densities of major vertebrate species, forest communities, and major forest stand structures are described. Big game utilization of ecotones created by mountain meadows and the lodgepole pine forest are discussed. In addition, the response of selected small mammal and big game species to clearcut size is provided. Important research findings were: (1) In the lodgepole pine forest most vertebrates exhibit preferences for specific community types. (2) Due to the broad definition of present habitat classifications, limited predictions can be made about the general response of wildlife populations on most sites. (3) The use of park-like openings and associated peripheral timber hy big game animals is closely associated with community type, edge configuration, and historical travel lanes. (4) An abundance of downed woody material enhances big game calving and resting areas. (S) The number of bird species is closely associated with understory biomass and diversity. (6) Management schemes that speed up the rotation of lodgepole pine overstories eliminate certain vertebrate communities associated with the final successional stages. The following specific recommendations for overstory removal are suggested. (1) Timber sales should be developed by drainage, with longterm objectives that insure the distribution of a variety of communities within a drainage. (2) The addition of major stand structure information should be included in habitat classification systems. (3) Timber sales should be designed with irregular edges and buffers of standing timber which provide cover and concealment. (4) Moist sites and relic areas, representing the final stages of succession, should be planned into the overall drainage sale philosophy. {5) In relatively undisturbed areas, vehicular travel should be prohibited following overstory removal.
265

Calcification and Productivity in a Dominant Shallow Water Reef Building Coral, Acropora palmata (Lamarck)

Gladfelter, Elizabeth H. 01 January 1977 (has links) (PDF)
Coral reefs are "constructional physiographic features of tropical seas consisting fundamentally of a rigid calcareous framework made up mainly of the interlocked and encrusting skeletons of reef-building (hermatypic) corals (Wells,1957). The principal organisms responsible for the construction of modern day coral reefs, the stony corals, comprise the cnidarian order Scleractinia, which is closely allied to the sea anemones (Actinaria). Individual polyps secrete a calcium carbonate skeletal cup (calyx) beneath the basal epidermis. In most coral species the polyps remain connected by living tissue forming a colony and calcium carbonate is deposited beneath the basal epidermis of the entire colony, thereby constructing a three-dimensional mass of calcium carbonate which increases in size with the passage of time. The living tissues of reef building corals are packed with unicellular symbiotic dinoflagellates termed zooxanthellae which have been shown to be of Importance in both the calcification of the skeleton and in production of organic material on the reef.
266

A Comparative Study of the Bottom Fauna of four Texas Lakes

Lamb, Leonard D. 08 1900 (has links)
This thesis attempted to study the bottom productivity both qualitatively and quantitatively with reference to the distribution of bonthos. The study of the bottom fauna in large reservior lakes is a relatively new field. This work will give more information on an unknown field than previously existed, although its scope is not intend to be exhaustive.
267

Dinosaurian Faunas of the Cedar Mountain Formation and LA-ICP-MS Detrital Zircon Ages for Three Stratigraphic Sections

Mori, Hirotsugu 23 November 2009 (has links) (PDF)
The Cedar Mountain Formation contains the most diverse record of Early Cretaceous dinosaurs in the western hemisphere. However, analyses of its faunas have been hindered because 1) most taxa are based on incomplete/fragmentary materials or incomplete descriptions, 2) most sites and some horizons preserve few taxa, and 3) the stratigraphy and geochronology are poorly understood. To help resolve these stratigraphic and correlation problems U-Pb LA-ICP-MS detrital zircon ages were obtained at significant sites and horizons. These dates indicate all sites at or near the base of the formation are no older than 122 to 124 Ma, thus all basal stratigraphic packages are time equivalent. Detrital zircons coarsely bracket the temporal span of the Ruby Ranch Member between about 115 Ma to 111 Ma while the base of the Mussentuchit Member is dated between 108 to 104 Ma and the top of the member is Cenomanian in age. Multivariate analyses utilizing Simpson and Raup-Crick similarity index and pair-group moving algorithms reveal that formationfs faunas fall into two groups. These groups are compared statistically with European, Asian, and Morrison faunas. Results indicate (1) that there is no close relationship between the Yellow Cat fauna and the Morrison Formation fauna and (2) corroborate long-standing hypotheses that the Yellow Cat fauna has European ties and the Mussentuchit fauna has Asian ties. Detrital zircon LA-ICP-MS U-Pb ages were used in this study to approximate the time of deposition of strata because volcanic ashes are rarely preserved in the formation. The ability to select the youngest crystals in a sample prior to applying analytical methods could substantially reduce the number of crystals and cost required to obtain these dates. To this end, the hypothesis that the most pristine, unabraded crystals should be younger than abraded crystals was tested by imaging detrital zircons via SEM, ranking the crystals by the degree of abrasion, and determining their ages. Results of this study partly corroborate the hypothesis in that there is a correlation between the degree of abrasion and ages – obviously abraded crystals are most likely the oldest while pristine to slightly abraded crystals are usually the youngest in a given sample.
268

Dynamic linkages between stratigraphy, climate, oceanography, and biotic events in the middle Silurian of eastern Laurentia

Thomka, James R. January 2015 (has links)
No description available.
269

Textural, mineralogical and structural controls on soil organic carbon retention in the Brazilian Cerrados

Zinn, Yuri Lopes 22 November 2005 (has links)
No description available.
270

Wildlife Information and Indigenous Culture Centre in Churchill, Manitoba: Where History is Exhibited and Experienced

Pavilanis, Claudia January 2023 (has links)
The abstract presents an architectural proposal for the Churchill Wildlife Information and Indigenous Culture Centre in Churchill, Northern Manitoba. The project aims to create a dynamic and educational space that showcases the town's rich history, celebrates its Indigenous heritage, and emphasizes the harmonious coexistence with the diverse local wildlife. Situated at the historically significant Rocket Range site, the centre seamlessly integrates with the natural landscape, offering visitors an immersive and captivating journey. Through carefully designed teaching spaces, interactive wildlife exhibitions, and curated displays of indigenous historical photographs, art, and artifacts, the centre provides a comprehensive exploration of Churchill's cultural and environmental heritage. Sustainability and cultural exchange are core principles guiding the design approach. The centre incorporates an artist-in-residence program, facilitating hands-on demonstrations of indigenous crafts while fostering dialogue and mutual learning. With a focus on addressing the need for an updated space that accurately reflects Churchill's unique culture and history, the centre endeavours to inspire a renewed connection with the environment and indigenous traditions. By promoting appreciation, knowledge, and a sense of responsibility towards wildlife, the centre aspires to become a beacon of education and conservation in Churchill's remarkable landscape.

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