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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.
141

Natural history and reproductive strategies of tropical reef algae, with an emphasis on the green algal order Bryopsidales and the genus Halimeda

Vroom, Peter S. January 2001 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 2001. / Includes bibliographical references. Also available on microfiche.
142

A case study of irgarol contamination in coastal environments /

Carbery Jr., Kelly K. January 2006 (has links) (PDF)
Thesis (M.S.)--University of Puerto Rico, Mayaguez Campus, 2006. / Tables Includes bibliographical references.
143

La Défense sanitaire maritime d'un port contre la peste.

Lequerré, G. January 1905 (has links)
Th.--Méd.--Paris, 1904-1905. / Paris, 1904-1905 t. 27, n ° 150.
144

Identifying Overwash Deposits in Arid Environments| Towards a Millennial-Scale Record of Cyclones and Makran Trench Tsunamis from Sur Lagoon, Oman

Griffis, Anne 15 May 2018 (has links)
<p> Coastlines along the Arabian Sea are susceptible to marine inundation from Makran Subduction Zone (MSZ) earthquakes and tropical cyclones. Sediments deposited by these forms of inundation can expand the decadal instrumental record of events to include millennial timescales in regions without rich historical records (i.e., Oman). On November 28, 1945 a 8.1 M<sub>w</sub> MSZ earthquake generated a tsunami that inundated coastlines of the Arabian sea with wave heights as high as 13m. The stratigraphic, sedimentological, foraminiferal, and geochemical signatures of deposit were examined from a small (12 km&sup2;), microtidal lagoon in Sur, Oman. The 1945 tsunami deposit contained distinctive taphonomic assemblages of foraminifera and bivalves. Below the 41cm thick 1945 shell-rich deposit at Sur Lagoon, seven additional anomalous sand (mean grain size of 3.73&phis; &plusmn; 1.66; very fine sand) layers, ranging in thickness from 7 to 32cm, were found preserved within fine-grained lagoonal sediment (mean grain size of 4.44&phis; &plusmn; 1.66; very coarse silt). The seven inferred overwash layers have features consistent with the 1945 tsunami deposit such as fining upward trends, marine foraminifera (e.g., <i> Amphistegina</i> spp., planktics) and increased concentrations of calcium and strontium. By contrast, the surrounding lagoon deposits contain finer grain sizes, intertidal and nearshore foraminifera (e.g., <i>Ammonia tepida</i>, miliolids), and increased concentrations of titanium and magnesium. Based on these data, the seven overwash layers found below the 1945 tsunami deposit have been attributed to marine inundation. Radiocarbon dating indicated an age of 3127 to 2515 cal yr BP for the deepest stratigraphic unit.</p><p>
145

Studies of Hypnea spicifera

Hewitt, Florence E January 1955 (has links)
No description available.
146

The uptake of arsenicals by the marine algae Isochrysis galbana and Dunaliella tertiolecta

Tsang, Angela Ka Yen January 1990 (has links)
Two marine algae, Isochrysis galbana and Dunaliella tertiolecta, were grown in the presence of arsenate, arsenite, monomethylarsonate (MMA), and dimethylarsinate (DMA). Cell growth was monitored by using in vivo fluorescence and cell density measurements. The effects of different levels of arsenicals on the arsenic uptake were examined using Hydride Generation Atomic Absorption (HGAA) Spectrometry and Graphite Furnace Atomic Absorption (GFAA) Spectrometry. The spin-echo ¹H NMR spectra of these algae are reported. Significant arsenic uptake and incorporation occurred when both algae were subjected to elevated levels of arsenicals. I. galbana was most affected by arsenite at the range of concentrations tested (2 - 8 ppm). Total incorporation is also the highest in this medium. The alga seems to be able to adapt to high arsenate concentrations. D. tertiolecta was most affected by elevated levels of arsenate (10.7 ppm). Water soluble extracts of algal cells grown in this medium contain at least four arsenicals which possibly include arsenate and arsenite. Growth of both algae was not affected by DMA at the levels examined. Growth enhancement is observed in all MMA treated cultures. Arsenic speciation of the residual media showed that both algae can reduce arsenate to arsenite. / Science, Faculty of / Chemistry, Department of / Graduate
147

Preliminary work on a tentative method for the estimation of iodine in sea-weeds

CHAN, Kwan Man 01 January 1939 (has links)
No description available.
148

Reproductive biology and diet of the St. Joseph (Callorhinchus capensis) in South Africa

Nibam, Abi Henry January 2011 (has links)
Includes abstract. / Includes bibliographical references (p. 72-84). / The reproductive biology of the commercially exploited fish St. Joseph or Cape Elephant fish Callorhinchus capensis, is described based on 173 fishes caught by gillnets in October 2010 from Velddrif along the west coast of South Africa. Segregation by sex was reflected by a difference in sex ratio from 1:1 for females to males fishes collected from the fishery (?2 = 16.23, d.f. = 1, p = 5.6 x 10-5).
149

Geological mapping of the inner shelf off Cape Town's Atlantic Seaboard, South Africa

Van Zyl, Frederik Wilhelm 19 February 2019 (has links)
The Atlantic Seaboard is an 18 km stretch of coastline located on the Cape Peninsula, South Africa, roughly between the Cape Town suburbs of Mouille Point in the north and Hout Bay in the south. It borders heavy shipping traffic and contains a mix of urban and natural environments including up-market seaside neighbourhoods and is part of the Table Mountain National Park. The predominantly rocky coastline has a northeast–southwest orientation with interspersed sandy pocket beaches. A narrow, low-lying coastal plain (marine terrace) in the north merges with coastal cliffs further south. The geomorphology and sedimentology of the coast are closely linked to the underlying geology, influencing the shape of coastal embayments and promontories, as well as the composition and distribution of sediment. Hydrographic, geophysical and sedimentological techniques were used to collect high-resolution bathymetry, seafloor geology and sediment distribution data to better understand modern coastal processes. The results indicate a low-relief seafloor consisting of Malmesbury Group rocks in the north. To the south the seafloor consists of high-relief Cape Granite reefs interspersed with fine to medium grain sand and bioclastic (shelly) gravel. Sediment transport is generally northward by longshore drift. In the south, the high-relief granite reef and headlands form sediment traps resulting in several large pocket beaches and offshore sediment deposits. In the north, the low-relief Malmesbury bedrock is largely free of sediment, except within narrow erosional gullies. Most sediment rapidly passes through to the north resulting in a sediment-starved rocky seafloor. The three principal sources of beach sand are aeolian fine sand transported by the Karbonkelberg headlands bypass dune entering the sea at Sandy Bay, biogenic carbonate production along the coast, and weathering of Table Mountain Group sandstone and granite bedrock. A fourth source is sediment entering the system via longshore drift from the south of Duiker Point. The water depth around the Duiker Point headland is presently too deep for sediment to be transported easily through longshore drift, other than during large storm events, but during past sea-level low stands this would have played an important part in supplying sediment to the coast. Changes in sea level play an important part in shaping the geomorphology of the coastline. Beach deposits, both sandy and boulder beaches have been left at various elevations along the coast, both offshore and onshore. Although today the Sea Point area is protected by sea walls and man-made structures, a higher sea level was responsible for shaping the narrow coastal plain. Increasing rates of global sea-level change are becoming an important issue all over the world and the Atlantic Seaboard coast is not immune to the effects of sea-level rise. The frequency and magnitude of storm events that breach the sea defences erode beaches and sea cliffs and cause damage to private and public property are likely to increase in the future
150

Entering murky legal waters transboundary impacts of acid mine drainage within the Limpopo river as potential breaches of South Africa's duty not to cause significant harm

Kinna, Rémy Paul January 2013 (has links)
Includes bibliographical references.

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