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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.
111

Algal-herbivore interactions in coastal communities in Tung Ping Chau, Hong Kong.

January 2005 (has links)
So Ka Yi Erica. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 243-255). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract --- p.iii / Contents --- p.ix / List of Tables --- p.xii / List of Figures --- p.xix / Chapter Chapter 1 --- General Introduction / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.2 --- General Objectives --- p.11 / Chapter 1.3 --- Study Site --- p.12 / Chapter 1.4 --- Organization of the Thesis --- p.13 / Chapter Chapter 2 --- "General Surveys on the Abundance of Algae and Herbivores in A Ma Wan, A Ye Wan and Lung Lok Shui, Tung Ping Chau, Hong Kong" / Chapter 2.1 --- Introduction --- p.16 / Chapter 2.2 --- Materials and Methods --- p.20 / Chapter 2.2.1 --- Study site --- p.20 / Chapter 2.2.2 --- Measurement of water temperature --- p.21 / Chapter 2.2.3 --- Measurement of algal percentage cover --- p.22 / Chapter 2.2.4 --- Measurement of herbivore density --- p.22 / Chapter 2.2.5 --- Investigation on the species richness and diversity of algae and herbivores --- p.23 / Chapter 2.2.6 --- Statistical analysis --- p.24 / Chapter 2.3 --- Results --- p.27 / Chapter 2.3.1 --- Measurement of algal abundance and diversity --- p.27 / Chapter 2.3.1.1 --- Percentage cover and morphology --- p.28 / Chapter 2.3.1.2 --- Species richness --- p.29 / Chapter 2.3.1.3 --- Species diversity --- p.29 / Chapter 2.3.1.4 --- Dominance and composition --- p.30 / Chapter 2.3.2 --- Measurement of herbivore abundance and diversity --- p.32 / Chapter 2.3.2.1 --- Density of herbivores --- p.32 / Chapter 2.3.2.2 --- Species richness --- p.33 / Chapter 2.3.2.3 --- Species diversity --- p.34 / Chapter 2.3.2.4 --- Dominance and composition --- p.34 / Chapter 2.3.3 --- Relationships between algae and herbivores --- p.37 / Chapter 2.3.3.1 --- Pairwise Pearson Correlation between algae and herbivores in different sites --- p.37 / Chapter 2.3.3.2 --- Canonical correlations between algal and herbivorous species --- p.38 / Chapter 2.3.4 --- "Water temperature and its relationships with the abundance, richness and diversity of algae and herbivores" --- p.39 / Chapter 2.4 --- Discussion --- p.40 / Chapter 2.4.1 --- Spatial distribution of algae and herbivores --- p.40 / Chapter 2.4.2 --- Seasonal distributions of algae and herbivores --- p.46 / Chapter 2.4.3 --- Interactions between algae and herbivores --- p.50 / Chapter Chapter 3 --- Growth of Algae in Herbivore-exclusion Manipulative Experiment / Chapter 3.1 --- Introduction --- p.106 / Chapter 3.2 --- Materials and Methods --- p.111 / Chapter 3.2.1 --- Study site --- p.111 / Chapter 3.2.2 --- Manipulative experiment --- p.111 / Chapter 3.2.3 --- Investigation on the manipulative experiment --- p.112 / Chapter 3.2.3.1 --- Species composition of algae and herbivores --- p.113 / Chapter 3.2.3.2 --- Percentage cover of algae and density of herbivores --- p.113 / Chapter 3.2.3.3 --- Sizes of herbivores --- p.113 / Chapter 3.2.4 --- Detecting the cage effect --- p.114 / Chapter 3.2.5 --- Statistical analyses --- p.114 / Chapter 3.3 --- Results --- p.117 / Chapter 3.3.1 --- Algae --- p.117 / Chapter 3.3.1.1 --- Percentage cover --- p.117 / Chapter 3.3.1.2 --- Species richness --- p.120 / Chapter 3.3.1.3 --- Composition between treatments --- p.121 / Chapter 3.3.1.4 --- Compositions between set-ups --- p.121 / Chapter 3.3.1.5 --- Effects from caging and clearing --- p.122 / Chapter 3.3.2 --- Herbivores --- p.123 / Chapter 3.3.2.1 --- Density --- p.123 / Chapter 3.3.2.2 --- Species richness --- p.124 / Chapter 3.3.2.3 --- Compositions between treatments --- p.124 / Chapter 3.3.2.4 --- Compositions between set-ups --- p.125 / Chapter 3.3.3 --- Relationships between algae and herbivores --- p.125 / Chapter 3.3.3.1 --- Abundance --- p.125 / Chapter 3.3.3.2 --- Composition --- p.126 / Chapter 3.3.4 --- Sizes of herbivores --- p.128 / Chapter 3.3.5 --- Irradiance between treatments --- p.128 / Chapter 3.4 --- Discussion --- p.129 / Chapter 3.4.1 --- Effects of clearing on algal and herbivore dynamics --- p.130 / Chapter 3.4.2 --- Effects of caging on algal and herbivore dynamics --- p.135 / Chapter 3.4.3 --- Effects of seasonality of clearing on algal and herbivore dynamics --- p.139 / Chapter 3.4.4 --- Interactions of algae and herbivores --- p.142 / Chapter Chapter 4 --- Feeding Behavior of Common Herbivores in the Artificial Food Experiment / Chapter 4.1 --- Introduction --- p.216 / Chapter 4.2 --- Materials and Methods --- p.218 / Chapter 4.2.1 --- Sample collections --- p.218 / Chapter 4.2.2 --- Production of artificial foods --- p.219 / Chapter 4.2.3 --- Feeding experiments --- p.219 / Chapter 4.2.4 --- Statistical analysis --- p.220 / Chapter 4.3 --- Results --- p.221 / Chapter 4.4 --- Discussion --- p.222 / Chapter Chapter 5 --- Summary and Conclusion --- p.233 / References --- p.243
112

Harmful algae from container ship ballast water taken from the open ocean and from Oakland, California (May, 1996 to April, 1997)

Zhang, Fangzhu., 張芳珠. January 1997 (has links)
published_or_final_version / Ecology and Biodiversity / Master / Master of Philosophy
113

Characterization of novel compounds isolated from Karenia brevis cultures

Truxal, Laura T. January 2008 (has links) (PDF)
Thesis (M.S.)--University of North Carolina Wilmington, 2008. / Includes appendixes. Title from PDF title page (viewed May 27, 2009) Includes bibliographical references (p. 96-102)
114

Turf algal/sediment (TAS) mats a chronic stressor on scleractinian corals in Akumal, México /

Roy, Roshan Elizabeth Ann, Theriot, Edward C., Lang, Judith C. January 2004 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2004. / Supervisors: Edward C. Theriot and Judith C. Lang. Vita. Includes bibliographical references.
115

The ecophysiology of Gelidium Pristoides (Turner) Kuetzing : towards commercial cultivation

Steyn, Paul-Pierre January 2009 (has links)
The ecophysiology of the red alga Gelidium pristoides (Turner) Kuetzing was investigated in an effort to establish a technique for commercial cultivation. The seaweed is of commercial importance in South Africa where it is harvested from the intertidal zone rocky shores along the coast. It is dried and exported abroad for the extraction of agar. Yields and quality could be improved by cultivation in commercial systems. However, attempts at growing the seaweed in experimental systems have all ended in failure. This study aimed to describe the conditions in which the seaweed grows naturally; and investigate its physiological response to selected physical conditions in the laboratory in order to determine suitable conditions for mariculture. Ecological studies showed that G. pristoides grew above the spring low tide water level. The upper limit of the seaweed’s vertical distribution range, as well as its abundance, was largely dependent on wave exposure. The zone normally inhabited by G. pristoides was dominated by coralline turf in sheltered areas, while the abundance of G. pristoides increased towards more exposed rocky shore sites. The seaweed occurred among species such as Pattelid limpets and barnacles, but was usually the dominant macroalga in this zone, with coralline turf and encrusting algae being the only others. Physical conditions in the part of the intertidal zone inhabited by G. pristoides were highly variable. During low tide temperatures could vary by as much as 10°C within the three hours between tidal inundation of the seaweed population, while salinity varied by up to 9 ppt, and light intensity by as much as 800 μmol m-2 s-1. During these exposure periods the seaweed suffered up to 20% moisture loss. Laboratory experiments on the seaweed’s response to these conditions indicated that it was well adapted to such fluctuations. It had a broad salinity (20 and 40 ppt), and temperature tolerance range (18 to 24°C), with an o ptimum of temperature of 21°C for photosynthesis, while there was no difference in the photosynthetic rate of the alga within the 20 to 40 ppt salinity range. The alga had a low saturating irradiance (ca. 45 – 80 μmol m-2 s-1) equipping it well for photosynthesis in turbulent environments, with high light attenuation, but poorly to unattenuated light conditions. Exposure resulted in an initial increase in photosynthetic rate followed by a gradual decrease thereafter. pH drift experiments showed that low seawater pH, and associated increased carbon dioxide availability, resulted in an increase in photosynthetic rate. This response suggests that the seaweed has a high affinity for carbon dioxide, while the reduction in photosynthetic rate in response to bicarbonate use inhibition indicates that it also has the capacity for bicarbonate use. The high affinity of Gelidium pristoides for carbon dioxide as an inorganic carbon source appears to be the primary reason for the low abundance of the alga on sheltered rocky shore areas, and also explains the failure of the alga to grow in tank or open-water mariculture systems. Exposed rocky shores have experience heavy wave action, and the resultant aeration and mixing of nearshore waters increases the availability of carbon dioxide, which is considered a limiting resource. The absence of such mixing and aeration at sheltered site makes this less suitable habitat for G. pristoides. Periodic exposure also makes high levels of atmospheric carbon dioxide available from which the seaweed benefits. The traditional mariculture systems in which attempts have been made to cultivate the seaweed failed to satisfy either of the above conditions.
116

Isolation and characterization of alginate from Hong Kong brown seaweed: an evaluation of the potential use of the extracted alginate as food ingredient.

January 2000 (has links)
by Li Yung Yung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 105-121). / Abstracts in English and Chinese. / ACKNOWLEDGEMENTS --- p.i / ABSTRACT (ENGLISH VERSION) --- p.ii / ABSTRACT (CHINESE VERSION) --- p.iv / TABLE OF CONTENTS --- p.v / LIST OF TABLES --- p.x / LIST OF FIGURES --- p.xi / LIST OF ABBREVIATIONS --- p.xiii / Chapter CHAPTER ONE --- INTRODUCTION / Chapter 1.1 --- Seaweed --- p.1 / Chapter 1.1.1 --- General Introduction --- p.1 / Chapter 1.1.2 --- Classification and Use of Seaweed --- p.1 / Chapter 1.1.3 --- Phycocolloids --- p.2 / Chapter 1.1.4 --- Hong Kong Seaweed --- p.3 / Chapter 1.1.4.1 --- Sargassum Species --- p.3 / Chapter 1.1.4.2 --- Padina Species --- p.5 / Chapter 1.2 --- Source and Production of Alginate --- p.8 / Chapter 1.2.1 --- Function of Alginate in Seaweed --- p.8 / Chapter 1.2.2 --- Chemical Structure of Alginate --- p.8 / Chapter 1.2.3 --- Alginate Production --- p.9 / Chapter 1.2.4 --- Isolation of Alginate --- p.13 / Chapter 1.2.5 --- Commercial Methods --- p.13 / Chapter 1.3 --- Application of Alginate --- p.14 / Chapter 1.3.1 --- Industrial Application --- p.14 / Chapter 1.3.2 --- Pharmaceutical Application --- p.16 / Chapter 1.3.3 --- Food Application --- p.17 / Chapter 1.3.3.1 --- Uses of Alginate in Food --- p.17 / Chapter 1.3.3.2 --- Safety --- p.19 / Chapter 1.4 --- Structure and Function Relationship of Alginate --- p.19 / Chapter 1.4.1 --- Physico-Chemical Properties --- p.21 / Chapter 1.4.1.1 --- M/G ratio --- p.21 / Chapter 1.4.1.2 --- Solution Properties --- p.21 / Chapter 1.4.1.3 --- Viscosity --- p.23 / Chapter 1.4.1.4 --- Molecular Weight --- p.27 / Chapter 1.4.2 --- Functional Properties --- p.27 / Chapter 1.4.2.1 --- Emulsion --- p.27 / Chapter 1.4.2.2 --- Gel Properties --- p.27 / Chapter 1.4.2.3 --- Mechanism of Gelation --- p.29 / Chapter 1.4.2.4 --- Gel Strength and Syneresis --- p.30 / Chapter 1.5 --- Physiological Effects --- p.32 / Chapter 1.5.1 --- Dietary Fibre --- p.32 / Chapter 1.5.2 --- Minerals --- p.32 / Chapter 1.6 --- Significance of the Present Study --- p.33 / Chapter CHAPTER TWO --- MATERIALS AND METHODS / Chapter 2.1 --- Seaweed Collection --- p.36 / Chapter 2.2 --- Sample Preparation --- p.36 / Chapter 2.3 --- Alginate Extraction --- p.38 / Chapter 2.3.1 --- Method A --- p.38 / Chapter 2.3.2 --- Method B --- p.38 / Chapter 2.3.3 --- Commercial Alginate --- p.39 / Chapter 2.4 --- Chemical Composition of Alginate --- p.41 / Chapter 2.4.1 --- Alginate Content --- p.41 / Chapter 2.4.2 --- Moisture Content --- p.41 / Chapter 2.4.3 --- Crude Protein Content --- p.41 / Chapter 2.4.4 --- Ash Content --- p.42 / Chapter 2.4.5 --- Monosaccharide Composition --- p.42 / Chapter 2.4.5.1 --- Acid Deploymerisation --- p.42 / Chapter 2.4.5.2 --- Neutral and Amino Sugar Derivatization --- p.42 / Chapter 2.4.5.3 --- Determination of Neutral Sugars by Gas Chromatography --- p.43 / Chapter 2.4.5.4 --- Uronic Acid Content --- p.44 / Chapter 2.4.6 --- Uronic Acid Block Composition --- p.44 / Chapter 2.4.6.1 --- "MG, MM and GG Block Determination" --- p.44 / Chapter 2.4.6.2 --- M/G Ratio Determination --- p.45 / Chapter 2.4.6.3 --- Phenol-Sulfuric Acid Method --- p.45 / Chapter 2.5 --- Physico-Chemical Properties of Alginate --- p.46 / Chapter 2.5.1 --- Viscosity --- p.46 / Chapter 2.5.1.1 --- Ostwald Viscometer --- p.46 / Chapter 2.5.1.2 --- Brookfield Viscometer --- p.47 / Chapter 2.5.2 --- Molecular Weight --- p.47 / Chapter 2.5.2.1 --- From Intrinsic Viscosity --- p.47 / Chapter 2.5.2.2 --- Gel Permeation Chromatography-Laser Light Scattering (GPC-LLS) --- p.48 / Chapter 2.6 --- Functional Properties of Alginate --- p.49 / Chapter 2.6.1 --- Emulsifying Activity (EA) and Emulsion Stability (ES) --- p.49 / Chapter 2.6.2 --- Gel Formation --- p.49 / Chapter 2.6.3 --- Gel Strength and Syneresis --- p.50 / Chapter 2.6.4 --- Application in Food ´ؤ Fruit Jelly --- p.52 / Chapter 2.7 --- Data Analysis --- p.53 / Chapter CHAPTER THREE --- RESULTS AND DISCUSSION / Chapter 3.1 --- Proximate Composition of Selected Seaweed --- p.54 / Chapter 3.1.1 --- Moisture Content --- p.54 / Chapter 3.1.2 --- Ash Content --- p.56 / Chapter 3.1.3 --- Crude Protein Content --- p.57 / Chapter 3.1.4 --- Carbohydrate Content --- p.58 / Chapter 3.2 --- Chemical Composition of Alginate Extracted from Two Different Methods --- p.58 / Chapter 3.2.1 --- Percentage Yield --- p.59 / Chapter 3.2.2 --- Alginate Content --- p.61 / Chapter 3.2.3 --- Moisture Content --- p.62 / Chapter 3.2.4 --- Ash Content --- p.62 / Chapter 3.2.5 --- Residual Protein Content --- p.63 / Chapter 3.2.6 --- Monosaccharide Composition of Alginate --- p.63 / Chapter 3.2.7 --- M/G Ratio --- p.66 / Chapter 3.2.8 --- Summary --- p.69 / Chapter 3.3 --- Comparative Studies of Physico-Chemical Composition of Alginate from Sargassum and Padina Species --- p.71 / Chapter 3.3.1 --- Block Composition and M/G Ratio --- p.71 / Chapter 3.3.2 --- Viscosity --- p.75 / Chapter 3.3.2.1 --- Intrinsic Viscosity ´ؤ Capillary Viscometer --- p.75 / Chapter 3.3.2.2 --- Solution Viscosity - Brookfield Viscometer --- p.79 / Chapter 3.3.2.2.1 --- Effect of Temperature --- p.79 / Chapter 3.3.2.2.2 --- Effect of Concentration --- p.81 / Chapter 3.3.2.2.3 --- Shear Thinning and Time Independent Effect --- p.82 / Chapter 3.3.3 --- Molecular Weight --- p.88 / Chapter 3.3.3.1 --- From Intrinsic Viscosity --- p.88 / Chapter 3.3.3.2 --- Gel Permeation Chromatograph-Laser Light Scattering (GPC-LLS) --- p.90 / Chapter 3.4 --- Comparative Studies of the Functional Properties of Extracted Alginate with Commercial Alginate --- p.93 / Chapter 3.4.1 --- Emulsifying Activity (EA) and Emulsifying Stability (ES) --- p.93 / Chapter 3.4.2 --- Gelling Properties --- p.95 / Chapter 3.4.2.1 --- Effect of Calcium Concentrations --- p.95 / Chapter 3.4.2.2 --- Gel Strength and Syneresis --- p.97 / Chapter 3.4.3 --- Application in Food --- p.99 / Chapter CHAPTER FOUR --- CONCLUSIONS --- p.103 / REFERENCES --- p.105 / RELATED PUBLICATION --- p.120
117

Studies on the marine algae of southern Australia / by H.B.S. Womersley / The marine algae of Kangaroo Island. 1-4 / Marine coastal zonation in southern Australia in relation to a general scheme of classification / A general account of the intertidal ecology of South Australian coasts / Protochara, a new genus of characeae from Western Australia / The archipelago of the recherche. 3b, Marine algae / The species of macrocystis with special reference to those on southern Australian coasts / Australian species of Sargassum subgenus Phyllotrichia / A new marine Vaucheria from Australia / New marine Chlorophyta from southern Australia / A critical survey of the marine algae of southern Australia. 1, Chlorophyta / The genus Codium (Chlorophyta) in southern Australia / Marine algae from Arnhem Land, North Australia / The structure and reproduction of Gulsonia annulata Harvey (Rhodophyta) / Studies on the Sarcomenia group of the Rhodophyta / The marine algae of Australia / A free floating marine red algae / Sympodophyllum, a new genus of Delesseriaceae (Rhodophyta) from South Australia / The structure and systematic position of the Australiasian brown alga, Notheia anomala / The structure and systematic position of the Australiasian brown alga, Notheia anomala / Australian species of Sargassum subgenus Anthropycus

Womersley, H. B. S. (Hugh Bryan Spencer), 1922-, University of Adelaide. Dept. of Botany January 1959 (has links)
"Adelaide, Dec. 1959." / Includes bibliographical references. / 1 v. (various pagings) : / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / The studies included in this thesis have been carried out since 1946 in the Department of Botany, University of Adelaide. The 25 papers, reprints from various journals, have been grouped in two sections; firstly those on intertidal ecology; secondly taxonomic studies (in order of publication). One paper on a freshwater Charophyte is also included. / Thesis (D.Sc.)--University of Adelaide, Dept. of Botany, 1959
118

Seasonal patterns of algal availability, influences on diet selection and fitness of the tropical crab grapsus albolineatus

Kennish, Robin. January 1995 (has links)
published_or_final_version / Ecology and Biodiversity / Doctoral / Doctor of Philosophy
119

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

Hutchinson, Neil. January 1999 (has links)
published_or_final_version / Ecology and Biodiversity / Doctoral / Doctor of Philosophy
120

Cytokinins in Ecklonia maxima and the effect of seaweed concentrate on plant growth.

Featonby-Smith, Bryan Charles. January 1984 (has links)
The endogenous cytokinin levels in the brown alga Ecklonia maxima (OSBECK) PAPENF., and the effect of applications of the seaweed concentrate (Kelpak 66) prepared from this alga, on the growth and yield of various plants was investigated. Tentative identification of the cytokinins present in Ecklonia maxima using High Performance Liquid Chromatography revealed the presence of cis and trans-ribosylzeatin, trans-zeatin, dihydrozeatin and isopentenyladenosine. Seasonal and lunar variations in the endogenous cytokinin levels in fresh and processed Ecklonia maxima material were investigated. Lamina, stipe and holdfast regions of one, two and three metre plants harvested from February 1981 until January 1982 together with samples of processed material from the normal production run, collected over the same period were used in this investigation. Analysis revealed both qualitative and quantitative changes in the cytokinin levels which were closely correlated to the seasonal patterns of growth of Ecklonia maxima. During summer zeatin, ribosylzeatin and their dihydroderivatives were responsible for most of the detected activity. The cytokinin glucosides increased above the levels of free cytokinins during winter. The lunar cycle study of material harvested on a daily basis during April - May 1983 revealed marked fluctuations in the cytokinin levels in the various tissues of two metre plants which were closely correlated with the phases of the moon. Greenhouse trials were conducted to determine the effects of the commercially available seaweed concentrate (Kelpak 66) on the growth of Lycopersicon esculentum MILL. plants in nematode infested soil. Kelpak 66 at a dilution of 1 : 500 improved the growth of treated plants significantly, irrespective of whether it was applied as a foliar spray at regular intervals, or whether the soil in which the plants were grown was flushed once with the diluted seaweed concentrate. Root growth was significantly improved whenever the seaweed concentrate was applied. Associated with this improved root growth was a reduction in the infestation of Meloidogyne incognita (KOIFORD and WHITE) CHITWOOD. Finally, the effect of seaweed concentrate and fertilizer applications on the growth and endogenous cytokinin content of Beta vulgaris L. and Phaseolus vulgaris L. plants was investigated. Seaweed concentrate at a dilution of 1 : 500 applied as a foliar spray improved the growth of treated plants significantly, irrespective of whether it was applied on its own or together with a chemical fertilizer. Root growth and the endogenous cytokinin content of these roots increased with seaweed concentrate application. Increases were also detected in the cytokinin content of fruits of Phaseolus vulgaris plants treated with seaweed concentrate. Associated with this increase in the cytokinin content was an increase in the dry mass of the fruit from treated plants. The significance of these findings and the possible relationship between the endogenous cytokinins present in Ecklonia maxima and the effect of the seaweed concentrate on plant growth is discussed. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1984.

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