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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.
31

The taxonomy, morphology and reproduction of the Myrionemaceae, Elachistaceae, Corynophlaeceae and Giraudyaceae (Phaeophyceae) in Southern Australian /

Skinner, Stephen. January 1980 (has links) (PDF)
Thesis (Ph.D.) -- University of Adelaide, Dept. of Botany, 1981. / Typescript (photocopy).
32

Effects of sedimentation on the structure of a phaeophycean dominated macroalgal community /

Turner, David J. January 2004 (has links) (PDF)
Thesis (Ph.D.)--University of Adelaide, School of Earth and Environmental Sciences, Discipline of Environmental Biology, 2005? / "July 2004" Includes bibliographical references (leaves 150-172). Also available electronically.
33

Production of docosahexaenoic acid by Crypthecodinium cohnii using continuous-mode process

Inan, Deniz. January 2008 (has links)
Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains viii, 95 p. : ill. (some col.). Includes abstract. Includes bibliographical references.
34

Spatial variation on tropical rocky shores the role of herbivory and disturbance /

Hutchinson, Neil. January 1999 (has links)
Thesis (Ph.D.)--University of Hong Kong, 2000. / Includes bibliographical references (leaves 220-255) Also available in print.
35

A study of the benthic algae in the kelp bed off Del Monte Beach, Monterey, California

Keithly, John Luther. January 1974 (has links)
Thesis (M.S.)--Naval Postgraduate School, 1974. / Includes bibliographical references (leaves 141-142).
36

Structure anatomique des mélobésiées (application à la classification)

Lemoine, Mme. Paul. January 1911 (has links)
Thése - Université de Paris. / From "Annales de l'Institut océanographique. t. II." "Liste des ouvrages cités": p. [201]-206.
37

Grazing, nutrients, and marine benthic algae : insights into the drivers and protection of diversity /

Guerry, Anne D., January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2006. / Printout. Includes bibliographical references (leaves 176-192). Also available on the World Wide Web.
38

An investigation into the primary productivity of the Antarctic macro-alga Phyllogigas grandifolius (A. & E.S. Gepp) Skottsb

Hastings, Robin M. January 1977 (has links)
The productivity of the large brown alga Phyllogigas grandifolius (A. & E.S. Gepp) Skottsb. has been studied over a period of 2 1⁄2 years. This alga is endemic to the Antarctic and circumpolar in distribution. Photosynthesis was measured in situ using SCUBA, Uptake of 14C-labelled sodium bicarbonate was used to obtain values for gross photosynthesis throughout the year, and by monitoring respiration at the same time using the Winkler technique a value for daily accretion could be found. The curves for daily accretion showed only one mm maximum per season, that at the deeper of the two sites occurring later than at the shallow site, as the light levels reaching the deeper algae continued to increase. Positive accretion expressed in mugC. cm-2.d-1 was observed only during the summer months. Maxima in 1974 were 70 mugC. cm-2.d-1 at the shallow site and 56 at the deep site. Respiration was low throughout the year as a result of the small annual range of water temperature (+1.5°C to -2°C). The mean respiratory rate was found to be 1.55 mugC. cm-2.h-1 Variation in the rate was observed along the length of the frond with the maximum occurring in the region of the meristem about 10cm. above the base of the frond. In situ studies of frond growth showed a complete cessation of growth during the winter months but recommenced before the departure of the sea-ice. This and day length appear to be the two main limiting factors of growth. Mean growth rate: 8.0mm. wk-1. With the growing season restricted, to 6 months, the mean productivity for that season was found to be 2.4 g C.m-2.d-1, with a photosynthetic efficiency of 14%. In the winter this efficiency drops to 1%. These figures were obtained from bomb calorimetry studies. Mannitol, the main storage product and primary respiratory substrate showed summer maxima of around 18% dry weight, falling to 2% during the winter. Due to the irregular distribution of the alga, biomass estimates are rather subjective. One of the denser 'stands' of Phyllogigas gave a figure of 0.813 kg. m-2 and a Leaf Area Index of 4.5. Other LAI values were as low as 0.0028. The mean SLA was 0.075. The net annual primary productivity was found to be 15.3 metric tons, hectare-1 year-1.
39

Studies on the biology of the economic marine red alga Gelidium pristoides (Turner) Kuetzing (Gelidiales : Rhodophyta)

Carter, Alan Robert January 1987 (has links)
Various aspects of the biology of the intertidal agarophyte, Gelidium pristoides, were investigated, with the aim of providing information that would assist in formulating a management policy for this economic seaweed resource. G.pristoides occurs as tufts comprising as many as 40 individual plants, representing all three conspicuous life history stages, that are linked by the intertwining of their basal creeping axes. Individual plants consist of a system of branched creeping axes, which is largely responsible for colonizing surrounding substrata, from which one or more erect flattened fronds arise. These erect fronds may reach a height of 15 cm, and are irregularly bipinnately branched. Internal vegetative anatomy is generally typical of the genus. Morphological variation in mature plants is limited to increased plant height and branch density during the summer season. A dorso-ventrally flattened creeping habit was seen during early recruitment on flat rock surfaces and limpet shells within grazer exclusion plots, which developed into typical erect plants. Although there is a close taxonomic affinity between G.pristoides and the low-growing Gelidium turf, which occurs on wave-cut platforms in the eastern Cape (both produce bispores), the turf appears to represent a genetically divergent ecotype of the typical G.pristoides habit. In the light of present observations, it is suggested that the recent inclusion of G.pristoides in the new Onikusa genus should be questioned. Reproduction in G.pristoides is typical of the genus, except for the production of bispores, instead of tetraspores, in the sporophyte generation. The smaller nuclei in the binucleate bispores, in comparison to carpospores, suggested they are the product of normal meiosis (meiospores). This was confi rmed by chromosome counts of germl i ngs deri ved from bispores (n = 13-17) and carpospores (2n = 28-33). Throughout the geographical range of the seaweed, the bisporophyte generation is dominant over the combined male and female gametophyte generati on by a ratio of about 3 : 1. This imbalance may be due to bispores. G.pristoides a greater germination success of carpospores over plants are fertile throughout the year, while at Port Alfred there is no apparent seasonality in spore release. Growth of carpospore and bispore germlings is similar under various temperature treatments in culture. Optimum temperatures for growth were from 15-23°C, which corresponds with the sea temperatures experienced within the geographical range of the species . At Port Alfred, growth (linear frond elongation) and standing crop levels were maximal during summer . Ory weight levels were significantly inversely related to both growth and ash levels. Agar contents (% of dry weight) were generally greater in summer (48% ) than in winter (30%), and were inversely correlated with thallus nitrogen levels. Agar contents of distal plant halves were higher (8-15%) than in proximal halves. Regrowth of G.pristoides to original biomass or standing crop levels after harvesting, is similar for plucking and shearing at different times of the year. Regrowth is more rapid after spring and summer harvests (2-3 months) than after winter harvests (4-5 months). During the summer season, harvesting at monthly intervals showed significantly greater total yields, and production rates (e.g . 3.13 g. dry wt. / m2 / day for plucking) than under 3-monthly intervals (1.42 g. dry wt. / m2 / day for plucking). In contrast, average yields per harvest were Significantly greater when recovery period was longer (e.g. 3 months). Quadrats that were completely denuded failed to recover after a year, while regrowth was also retarded with increased elevation on the shore. Agar contents did not differ Significantly between plucked (38%) and sheared (42%) plant material. G.pristoides is distributed from about 0 . 2-0.75 m above MLWS, with a reduction in stature and frequency corresponding to increased elevation on the shore. Frond elongation rates, germling survival and recruitment within grazer-exclusion plots, is retarded with increased elevation level. Plants transplanted above the normal vertical range of the seaweed became severely bleached and died, while plants transplanted below the normal range of the seaweed (sub littoral fringe) senesced due to overgrowth by the epiphytic encrusting coralline, Polyporolithon patena (Hook . et Harv . ) Mason . G.pristoides recrui t ment in the sublittoral fri nge was enhanced with the exclusion of grazers . However, successful recruits were displaced due to smothering by articulated corallines (e.g. Corallina sp. and Jania sp. ) . G.pristoides is largely restricted to cracks and crevices in the rock, and also occurs on a large proportion of the available shells of the limpet Patella oculus Born., and to a lesser extent, shells of the barnacle Tetraclita serrata. G.pristoides recruitment was significantly enhanced by the exclusion of grazers (using toxic antifouling paint barriers). G.pristoides recruitment within the exclusion plots was significantly greater on artificially attached limpet shells (almost 100% cover) than on rock surfaces (20-30% cover), which occurred largely within cracks and crevies in the rocky substratum. ly attached to limpet G.pristoides plants are significantly more strongand barnacle shells than to rock and epilithic encrusting corallines (Lithothamnion sp.). Removal of G.pristoides from limpet shells revealed pits of a uniform size in the surface of the shells, into which the rhizoidal attachment organs of the seaweed penetrate. It is concluded that the horizontal distribution of G.pristoides is largely controlled by grazers (and "escapes" from grazing) and resistance to dislodgement by wave action. Based on present results, and considering some of the socio-economic factors associated with the Gelidium industry in South Africa, suggestions are made concerning the management and long-term maintenance of G.pristoides resources in the eastern Cape.
40

A structural investigation of the sulphated polysaccharides of Aeodes orbitosa and Phyllymenia cornea

Parolis, Haralambos January 1968 (has links)
A highly sulphated, methylated polysaccharide, aeodan, isolated from the red seaweed Aeodes orbitosa was shown to contain galactose, 2-̲̲O-methyl-D-galactose, 4-O̲-methyl-Lgalactose, 6-O̲-methyl-D-galactose, xylose, and glycerol. The polysaccharide was desulphated with methanolic hydrogen chloride. Periodate oxidation of aeodan and desulphated aeodan, followed by reduction and hydrolysis, revealed the presence of 1,4- and 1,3-linked galactose residues and 1,3-linked 6-O̲-methy l-D-galactose residues in aeodan. Treatment of aeodan with sodium hydroxide revealed that the majority of the ester sulphate groups were alkali stable. Methylation of desulphated aeodan revealed that the polysaccharide was composed entirely of 1,3 and 1,4 links. Methylation of aeodan revealed the presence of 1,3- and 1,4- linked units, 1,3-linked galactose-2-sulphate, and 1,3-linked galactose-2, 6-disulphate units in the polysaccharide. Partial hydrolysis of aeodan resulted in the isolation and characterisation of 3-O̲-D-galactopyranosyl-D-galactose and 4-O̲-ß-D-galactopyranosyl- D-galactose. A sulphated, methylated polysaccharide, phyllymenan, isolated from the red seaweed Phyllymenia cornea was shown to contain galactose, 2-O̲-methyl-D-galactose, 4-O̲-methyl L- galactose , 6-O̲-methyl -D-galactose, and xylose. The polysaccharide was completely desulphated with methanolic hydrogen chloride. Periodate oxidation of phyllymenan before and after desulphation revealed that removal of the sulphate ester groups had not produced any new adjacent hydroxyl groups. Alkali treatment of phyllymenan revealed that the ester sulphate groups were alkali stable. Methylation studies on phyllymenan revealed the presence of 1,3- and 1,4-linked units, 1,3-linked galactose-2-sulphate, and 1,3-linked galactose- 2,6-disulphate units in the polysaccharide. Partial hydrolysis of phyllymenan revealed the presence or 4-O-̲ß- D-Dgalactopyranosyl- D-galactosc, 4-O-̲ß-D-galactopyranosyl -2-0- methyl-D-galactose, a galactosylgalactose composed of D and L-galactose, and adjacent 6-O̲-methyl- and 2-O̲-methyl-D- galactose units in the polysaccharide.

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