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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.
11

Administering the port of Hong Kong

Leung, Yuk-kwan. January 1988 (has links)
Thesis (M.Soc.Sc.)--University of Hong Kong, 1988. / Also available in print.
12

Genetic structure and physiological variation of a widespread European lagoon specialist Cerastoderma glaucum (Bivalvia) living in extreme environmental conditions / Structure génétique et variation physiologique chez Cerastoderma glaucum (Bivalvia) vivant dans des conditions environnementales différentes

Tarnowska, Katarzyna 25 March 2010 (has links)
Cette thèse de doctorat est un projet franco-polonais en co-tutelle entre le Département du Fonctionnement des Ecosystèmes Marins (l'Université de Gdansk, Pologne) et le laboratoire DIMAR (l'Université de la Méditerranée, France). La variation physiologique et la structure génétique des populations d’une espèce lagunaire, le bivalve, Cerastoderma glaucum, ont été étudiées. C. glaucum est une espèce sessile avec une phase larvaire planctonique. Elle est présente surtout dans les bassins isolés ou semi-isolés sans marée, comme les lagunes, les estuaires, les baies et les lacs. Ces habitats sont extrêmes de par des changements de conditions environnementales à court terme plus importants que dans le milieu marin. Ils sont souvent isolés, le flux de gènes est limité et des adaptations locales sont attendues. C. glaucum a révélé une forte variabilité des paramètres morphométriques et physiologiques entre les 3 populations de la Mer Baltique, la Mer du Nord et la Méditerranée. Les coques de la Mer Baltique sont beaucoup plus petites que celles des autres populations et leur taux de respiration est le plus élevé, ce qui est probablement provoqué par le stress osmotique. Les populations de l’Europe du nord ont un pattern de la reproduction monocyclique, tandis que la population de la Méditerranée peut se reproduire tout au long de l’année. Les changements saisonniers dans la composition biochimique sont corrélés avec les changements de condition trophique et avec le cycle reproductif. / This PhD is a Polish-French project between the Department of Marine Ecosystems Functioning (University of Gdansk, Poland) and DIMAR laboratory (Université de la Méditerranée, France). Physiological variation and genetic structure of the populations of lagoon specialist, the bivalve, Cerastoderma glaucum, have been studied. C. glaucum is a sessile species with a planctonic larval stage. It inhabits mainly non-tidal areas, like lagoons or brackish lakes. Those habitats are extreme, because they are much more subject to short-term variations in environmental conditions than marine habitats. They are also often isolated and as a consequence the gene flow among populations is limited and local adaptations are expected. The lagoon cockle revealed a strong interpopulation variability of morphometric and physiological parameters among 3 populations studied: from the Baltic Sea, the North Sea, and the Mediterranean Sea. The cockles from the Baltic Sea were much smaller than those from other populations and they exhibited the highest respiration rate, probably due to osmotic stress. The populations from the northern Europe had a monocyclic reproductive pattern, whereas the Mediterranean population seemed to reproduce throughout the year. Seasonal changes in biochemical components contents appeared to be correlated with changes in trophic conditions and the reproductive cycle. High respiration rates in populations from the northern Europe in spring and autumn could have resulted from gamete development (in spring) and phytoplankton blooms (in spring and autumn).
13

Aspects of the ecology of the common raven in Harney Basin, Oregon

Stiehl, Richard B. 01 January 1978 (has links)
Common Ravens (Corvus corax L.) have been implicated as significant predators on the eggs of waterfowl and shorebirds on Malheur National Wildlife Refuge. Malheur Refuge, located in southeastern Oregon on the northern edge of the Great Basin, is one of the largest waterfowl refuges in the United States and is an important breeding area for waterfowl. In order to provide fundamental information on which a sound raven management plan could be based, research was conducted from 1975-1977 on aspects of population density, brood phenology, nesting success, seasonal use of the study area, roosting behavior, and food habits of ravens on and near the refuge. Nesting density was determined to be one pair per approximately 25 km2 . Most nests occurred in rimrocks, but trees and abandoned human structures were also used. Investigation of 87 nests revealed that the incubation period was 21 + 1 days. Incubation began with the laying of the first egg; hatching was asynchronous. Nesting period was 41 + 3 days. An original method of age-classing ravens is described. A total of 266 ravens was marked with patagial tags. Observation of marked individuals as far as 480 km from the study area suggests considerable mobility in the population. Population numbers vary seasonally, peaking in the winter. The Harney Basin is the location of an exceptionally large winter roost for ravens. Analysis of food remains, collected from 34 nests, indicates that ravens have varied diets and that there are significant differences in the diets of ravens nesting in different habitats. A correlation exists between the proportion of the diet that is avian material and the proximity of the raven nest to waterfowl production areas. Based on these findings, suggestions are offered for a management plan for Common Ravens on Malheur National Wildlife Refuge.
14

Places of refuge and the obligation to accommodate ships in distress

Ucar, Zeynep. January 2006 (has links)
No description available.
15

Perspectives

Dottin, Danielle Amanda 18 July 2023 (has links)
The five senses are something we rely on to perceive our external world. Through an architectural sense, meditative and relaxing experiences establish themselves. How one is influenced by their surroundings a sense of self sparks a connection between body and place. Architecture, along with the phenomenon of synesthesia, brings another level of understanding of the world. With architectural spaces that enclose and water, a sense can be amplified and advanced to the forefront of the accompanying senses. Through the perception of one sense through another, the question of how the senses are in association with each other arises. With being submerged underground, a meditative refuge for the self embodies the five senses and the sense - less. Sight, touch, smell, taste, and sound work collectively to convey the experience of synesthesia. The perception of senses through another creates unique experiences and evokes self awareness. / Master of Architecture / The five senses [ sight, touch, hearing, smell, and taste ] are something we rely on to perceive our external world. Through an architecture of sense, meditative and relaxing experiences establish themselves. This sense of self sparks a connection between body and place. Architecture, along with the phenomenon of synesthesia, brings another level of understanding of the world. With architecture and water, a sense can be amplified and advanced to the forefront of the accompanying senses. Through the perception of one sense through another, the question of how the senses are in association with each other arises.
16

Control of Lepidium latifolium and restoration of native grasses

Laws, Margaret S. 23 November 1999 (has links)
Lepidium latifolium L. (perennial pepperweed, LEPLA) is an exotic invader throughout western North America. At Malheur National Wildlife Refuge (MNWR) in southeast Oregon, it has invaded about 10% of meadow habitats that are important for wildlife. This study's objective was to determine the most effective and least environmentally harmful treatment to control this weed and restore native vegetation using integrated pest management techniques. During summer 1995, nine 0.24-ha plots in three meadows infested with L. latifolium at MNWR were randomly assigned to a treatment with metsulfuron methyl herbicide, chlorsulfuron herbicide, disking, burning, herbicide (metsulfuron methyl or chlorsulfuron) then disking, herbicide (metsulfuron methyl or chlorsulfuron) then burning, or untreated. Changes in L. latifolium ramet densities and basal cover of vegetation, litter, and bare soil were evaluated in 1996 and 1997. Sheep grazing was evaluated as a treatment for reduction in flower production along roadsides and levees during summer 1997. Revegetation treatments of seeding, transplanting or natural (untreated) revegetation were attempted at plots treated with chlorsulfuron, disking, chlorsulfuron then disking, and at untreated plots from October 1996 through September 1997. Chlorsulfuron was the most effective control treatment with greater than 97% reduction in L. latifolium ramet densities two years after treatment. Metsulfuron methyl was an effective control (greater than 93% reduction) for one year. Disking was ineffective. Burning was ineffective at the one site where sufficient fine fuels existed to carry fire. Herbicide treatments were associated with increased grass and reduced forb cover. Disking was associated with reduced grass and litter cover. Disking combined with either herbicide treatment was associated with reductions in all plant cover (49 to 100%), increased bare ground, and invasion by other weedy species such as Cirsium arvense (L.) Scop. (Canada thistle, CIRAR) and Bromus tectorum L. (cheatgrass, BROTE). Ungrazed L. latifolium averaged 4513 flowers per ramet. Sheep grazing reduced L. latifolium flower production by at least 98%. Revegetation treatments were unnecessary in sites treated with chlorsulfuron and were ineffective at all treatment sites. / Graduation date: 2000
17

Monitoring changes in plant community composition and landscape structure as a result of prescribed burning at Big Oaks National Wildlife Refuge

Basey, Gary L. 03 June 2011 (has links)
A vegetation monitoring program was initiated at Big Oaks National Wildlife Refuge (Big Oaks NWR) to help understand the effects of fire management on critical wildlife habitat. The objectives of this study were to produce a baseline description of plant community structure and composition and to describe the landscape-level impacts of fire management within the refuge. These grassland communities are important for managing rare grassland wildlife species, especially Henslow's sparrows. Permanent plots were established in three managed grassland communities. Information on plant community species composition and structure was collected during 2000-2001. Andropogon viginiana and Solidago juncea were the dominant plant species in the permanent plots. Rhus copallinum and Liquidamber styraciflua were the dominant woody species. Changes in landscape structure were determined using aerial photographs and a geographic information system (GIS). Vegetation data layers were created for 1995 and 1998 with vegetation patches classified using the National Vegetation Classification System (NVCS). Field data was collected during 2000 and 2001 to validate the data layers. Changes in composition and structure of nine vegetation classes were compared between burned and unburned areas. Percent cover of grassland area increased while sparse woodland and shrubland decreased during the study period. The amount of total patches and total edge declined in the burn areas. Mean grassland patch size increased while the number of grassland patches and grassland edge decreased in the burn areas. Therefore, the grassland areas within the burn units were more homogeneous in 1998. The results of this study were related to Henslow's sparrow population estimates in the fire management units.
18

Woody plant species composition in forest fragments at Muscatatuck National Wildlife Refuge

Fribley, Laura A. January 2006 (has links)
Several invasive woody plants grow in forest fragments at Muscatatuck National Wildlife Refuge in Seymour, Indiana. The objective of this study was to determine what woody species were growing in two upland forests and to assess the level of dominance that invasive species had in these areas. The variables of depth into the forest and directional aspect were also considered. Thirty-two belt transects were sampled and 54 woody species were found, including six invasive species: Ailanthus altissima (tree-ofheaven), Berberis thunbergii (Japanese barberry), Elaeagnus umbellata (autumn olive), Lonicera japonica (Japanese honeysuckle), Lonicera maackii (amur honeysuckle), and Rosa multiflora (multiflora rose). Importance values were calculated as an indicator of relative species dominance. Detrended Correspondence Analysis and Cluster analysis suggested that the invasive species were grouped on the forest edge transects; aspect was not found to be a determinant in where invasive species grew. Correlation coefficients demonstrated a significant difference between transect depth and the following variables at both forests: woody species density per transect, invasive species dominance, Elaeagnus umbellata density per hectare, and Lonicera japonica dominance. Rosa multiflora was one of the three most dominant understory species in both forests; on the edge transect, it was one of the top two. Soil temperatures were also measured at each transect, but no consistent trends were found within the data. In light of resources available, it is suggested that land managers focus on controlling Rosa multiflora and Ailanthus altissima. / Department of Natural Resources and Environmental Management
19

Passerine nest ecology in managed, mixed-grass prairie /

Kerns, Courtney K. January 2004 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Includes bibliographical references. Also available on the Internet.
20

Passerine nest ecology in managed, mixed-grass prairie

Kerns, Courtney K. January 2004 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Includes bibliographical references. Also available on the Internet.

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