• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 478
  • 77
  • 34
  • 18
  • 10
  • 8
  • 8
  • 8
  • 8
  • 8
  • 7
  • 5
  • 2
  • 1
  • 1
  • Tagged with
  • 741
  • 406
  • 270
  • 222
  • 221
  • 217
  • 213
  • 206
  • 204
  • 199
  • 196
  • 196
  • 196
  • 95
  • 87
  • 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.
181

Temperate urban mangrove forests : their ecological linkages with adjacent habitats

Yerman, Michelle N., University of Western Sydney, College of Science, Technology and Environment, School of Natural Sciences January 2003 (has links)
Estuarine habitats along the temperate south-eastern shores of Australia are generally made up of salt marsh, mangrove forests and seagrass beds. In urban areas these habitats have been progressively fragmented as a result of population increase and industrial expansion. Salt marshes in particular have been vulnerable to urban expansion and reclamation because of their close proximity to densely populated areas, while mangrove forests have been less often reclaimed because of frequent tidal inundation. The effect of reclamation of salt marshes on the biotic assemblages and functioning of mangrove forests with an adjacent salt marsh, park or bund wall was examined at nine separate locations on the Parramatta River, Sydney NSW. A mensurative approach was used to describe the patterns of distribution and abundance of macro fauna at several temporal and spatial scales. The implications for management are that salt marshes are an integral part of estuaries, and smaller patches of salt marsh are just as important as larger patches in maintaining the diversity of faunal assemblages and ecosystem functioning in mangrove forests in urban areas / Master of Science (Hons)
182

Ecology of benthic microalgae of estuarine intertidal sediments

Riznyk, Raymond Zenon 09 May 1969 (has links)
The benthic microalgae of sediments of the two tidal flats in Yaquina Bay, Oregon were investigated to determine the environmental factors limiting the abundance and the horizontal and vertical distribution of these organisms. The Southbeach tidal flat which is under the marine realm of deposition consists of fine to medium grained sand. The Sally's Bend tidal flat is under the fluviatile realm of deposition and consists of silt. Measurements were made of interstitial temperatures, movements of sand, turbidity, pH, salinity, depth of light penetration through the sediments, and the water content of the substrate. Samples of the benthic microalgal community were collected by using a piston corer. Sections of the cores were used for estimating the biomass: (1) by making direct counts of live microalgae, (2) by estimating chlorophyll a concentration and (3) by measuring ash-free dry weight. The greatest biomass of microalgae was found to be in cores from the lower intertidal zone while cores from the upper intertidal zone had the lowest biomass. This distribution probably results from the greater fluctuations in temperature, salinity, water content, and oxygen content, which are more variable in the upper intertidal zone. The greater biomass in cores from the lower intertidal zone may be the result of less fluctuation in environmental factors as well as the fact that this area is exposed to nutrient-laden water for longer periods of time than the upper intertidal zone. The greatest biomass of microalgae was found in the upper centimeter of cores collected at all levels of the intertidal zone, because light can penetrate no more than a few millimeters through sediment. Occurrence of algae below the photic zone is thought to result from vertical migration, sedimentation, or the activity of burrowing animals. It was found that the Southbeach tidal flat had a significantly greater biomass than Sally's Bend at all intertidal levels and in the various layers of the cores. This was attributed to differences in environmental conditions peculiar to each tidal flat which is the result of the hydrography of the bay. Estimates of the rates of potential gross production were made using a Gilson Differential Respirometer. The community from the Southbeach tidal flat had a greater potential gross rate of production than the Sally's Bend community. This was partially the result of high rates of bacterial respiration in cores from the Sally's Bend tidal flat. This tidal flat had significantly greater amounts of organic matter than Southbeach and the abundance of bacteria in sediment is related to the amount of organic matter. Measurements of the concentrations of chlorophyll a were corrected for the percentage of pheophytin present. Significantly greater amounts of pheophytin were found in cores from the Sally's Bend tidal flat which probably resulted from the large amounts of allochthonous detrital chlorophyll deposited in these sediments. The microflora consisted almost exclusively of diatoms. One hundred and fifty-four species and varieties were identified. Most of the species found in the lower intertidal zone were found in the mid and upper intertidal zones as well. Many of the species identified have never been reported from Oregon prior to this investigation. / Graduation date: 1969
183

Numerical study in Delaware Inland Bays

Xu, Long. January 2006 (has links)
Thesis (M.C.E.)--University of Delaware, 2006. / Principal faculty advisors: Dominic M. Di Toro and James T. Kirby, Dept. of Civil & Environmental Engineering. Includes bibliographical references.
184

The Fly estuarine delta, Gulf of Papua, Papua New Guinea a discussion on the genesis, sedimentation and geological evolution of tidal seas, shelves and estuarine deltas with experimentation into the application of microsedimentary techniques to expedite the identification of ancient estuarine delta sands /

Spencer, Lynton Keith. January 1978 (has links)
Thesis (M. Sc.)--University of Sydney, 1980. / Includes diagrams, graphs, tables. Bibliography: leaves 136-157. Also available in print form.
185

The transport, transformation, and trophic transfer of bioactive metals in an urban impacted buoyant river plume

Wright, Derek D. January 2008 (has links)
Thesis (Ph. D.)--Rutgers University, 2008. / "Graduate Program in Environmental Sciences." Includes bibliographical references.
186

Growth, residence, and movement of juvenile Chinook salmon within restored and reference estuarine marsh channels in Salmon River, Oregon /

Hering, David K. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 130-142). Also available on the World Wide Web.
187

English sole transport during pelagic stages on the Pacific Northwest coast and habitat use by juvenile flatfish in Oregon and Washington estuaries /

Rooper, Christopher Nethercote. January 2002 (has links)
Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (leaves 228-246).
188

Interactions between oyster reefs and adjacent sandflats : effects on microphytobenthos and sediment characteristics /

Molesky, Thomas J. January 2003 (has links)
Thesis (M.S.)--University of North Carolina at Wilmington, 2003. / Includes bibliographical references (leaves : [45]-52).
189

Transport and deposition of high-concentration suspensions of cohesive sediment in a macrotidal estuary /

Guan, Weibing. January 2003 (has links)
Thesis (Ph. D.)--Hong Kong University of Science and Technology, 2003. / Includes bibliographical references (leaves 174-185). Also available in electronic version. Access restricted to campus users.
190

The role of benthic macrofauna in influencing fluxes and speciation of dissolved zinc and copper in estuarine sediments /

MacGillivray, Kenneth A., January 2003 (has links)
Thesis (M.S.)--University of North Carolina at Wilmington, 2003. / Vita. Includes bibliographical references (leaves : [37]-40).

Page generated in 0.0442 seconds