Thesis (M. Phil.)--University of Hong Kong, 2000. / Includes bibliographical references (leaves 144-162).

Thesis (Ph. D.)--University of Chicago. / Reprinted from the Botanical Gazette, Vol. 41, no. 3 (March 1906). Includes bibliographical references. Also available on the Internet.

Chan Wai Yi. / Thesis submitted in: November 2002. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 125-144). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.iv / Table of Contents --- p.v / List of Figures --- p.vii / List of Tables --- p.x / Chapter CHAPTER ONE: --- General Introduction --- p.1 / Resource Allocation and Life History --- p.1 / Cost of Reproduction in Plants --- p.4 / Life Histories and Cost of Reproduction in Algae --- p.5 / Importance of Sargassum Communities --- p.6 / The Marine Environment and Sargassum Communities in Hong Kong --- p.8 / Study Organism and General Objective of this Study --- p.9 / "Study Site: Lung Lok Shui, Tung Ping Chau" --- p.10 / Organization of The Thesis --- p.11 / Chapter CHAPTER TWO: --- Phenology of Sargassum siliquastrum --- p.15 / INTRODUCTION --- p.15 / MATERIALS AND METHODS --- p.20 / "Seasonal Change on Size, Growth, Density and Population structure" --- p.20 / Percentage of Reproduction --- p.21 / "Comparisons of “Deep ´ح and ""Shallow ´ح Water Populations" --- p.21 / Seasonal Change in Physical Parameters --- p.22 / Statistical Analysis --- p.22 / RESULTS --- p.23 / "General Seasonal Trends on Size, Growth and Biomass of the Deep Water Population" --- p.23 / Mean Density and Population Structure --- p.25 / Reproductive Phenology --- p.27 / Comparisons of Shallow and Deep Water Populations --- p.28 / "Seasonal Trends of Physical Parameters and Their Correlation with the Size, Growth and Reproduction of the Populations" --- p.30 / DISCUSSION --- p.32 / Chapter CHAPTER THREE: --- Cost of Reproduction in S. siliquastrum --- p.66 / INTRODUCTION --- p.66 / MATERIALS AND METHODS --- p.68 / Resource Allocation in Sargassum siliquastrum --- p.68 / Cost of Reproduction on Survival --- p.69 / Cost of Reproduction on Growth --- p.71 / Effect of Present Reproduction on Future Reproduction --- p.71 / Statistical Analysis --- p.72 / RESULTS --- p.73 / Resource Allocation in Sargassum siliquastrum --- p.73 / Cost of Reproduction on Survival --- p.76 / Cost of Reproduction on Growth --- p.80 / Effect of Present Reproduction on Future Reproduction --- p.81 / DISCUSSION --- p.85 / CHAPTER FOUR: Summary --- p.118 / REFERENCES --- p.125

The different period of growth and reproduction in the life cycle of organisms implied that the limited resources within their bodies have to be allocated between different processes as a 'trade-off'. Therefore, it would be important to understand how they adapt to the environment by understanding their life history, how they allocate their resources in different life stages and the strategies they adopt when there are changes in their living condition. / Sargassum siliquastrum is a dominant alga in Hong Kong. How it allocates its resources to growth and reproduction was examined in this thesis research. Its phenology in Lung Lok Shiu of Tung Ping Chau Marine Park, Hong Kong was studied by general monthly quadrat survey from September 2004 to May 2006. The four typical developmental stages of regeneration (slow growth), active growth, reproductive and senescence (die back) stage were observed. Maxima in length (90.28 士 45.13 cm in January 2005; 70.18 土 18.65 cm in February 2006), number of main axes (2.21 士 0.81 main axes in January 2005; 2.29 士 0.47 main axes in December 2005), number of size class 1 (l-3cm) new shoots (6.71 士 3.05 new shoots in February 2005; 5.18 士 1.39 new shoots in January 2006), number of size class 2 / (>3-5cm) new shoots (2.53 士 1.23 new shoots in February 2005), fertility (70.59 士 33.08% in January 2005; 77.74 士 17.94% in February 2006) and reproductive effort (21.13 土 7.59% in December 2004; 10.80 士 7.24% in February 2006) of the population were recorded in winter, and their minima were obtained in summer. In contrast, density of the population was highest during the slow growth stage in summer (90.50 士 62.78 individuals / m2 in July 2005), and lowest during its reproductive months (35 士 41.33 individuals / m2 in January 2005; 23.50 士 11.00 individuals / m2 in December 2005). Among the physical parameters evaluated, cooler temperature and decreasing day-length from summer to winter was found to favor the growth in length of the population whereas production of receptacles was favored by low water temperature and short day-length. / The seasonal and individual variations (between holdfast, basal, middle, top blade regions and receptacles) of the reserve sugar alcohol, mannitol, in Sargassum siliquastrum collected monthly from December 2003 to May 2006 were investigated using the HPLC technique. Seasonal variation of its mannitol content ranged from about 1% to 17% of its dry weight. Mannitol content increased as growth proceeded and peaked during the active growing stage (10.81 士 4.87 g mannitol/ lOOg dry seaweed in September 2004; 13.17 士 5.60 g mannitol/ lOOg dry seaweed in October / 2005). A drop in mannitol content was recorded only at the start of the reproductive period in December and remained stable thereafter. Dramatic decrease in mannitol concentration occurred after the reproductive period and a small increase in mannitol content was identified in the middle of the slow growth stage in April (5.69 士 2.11 g mannitol/ lOOg dry seaweed in 2004; 5.91 士 3.71 g mannitol/ lOOg dry seaweed in 2005; 17.87 ± 7.46 g mannitol/ lOOg dry seaweed in 2006), suggesting that the surplus produced during the slow growth period may be used to maintain the perennial holdfast or to develop new shoots for the next season. On an individual level, more mature basal part of the plant (i.e. holdfast and basal blade region) contained higher levels of mannitol when compared with the younger middle and top blade regions. Receptacles of S. siliquastrum displayed the lowest mannitol content, which appeared to match its low photosynthetic activity. The disproportionally high level of mannitol in the photosynthetically less active holdfast suggested that mannitol may be diffused from the basal blades down to the holdfast. The positive correlation between the two months antecedent mannitol content in the basal parts of S. siliquastrum plant with its various population growth parameters (e.g. plant mean length, number of main axes and new shoots) implied that storage compounds in the holdfast and basal blade regions were utilized for the development and elongation of / new shoots. / Manipulative experiments were performed to test the hypotheses that reduced resources would lead to reduced growth and reproduction in Sargassum siliquastrum and that holdfast plays an important role for nutrient storage. Both hypotheses were supported by experimental data in this study. Vegetative shoots of tagged individuals were either trimmed to 15cm in length or removed down to the holdfast before the active growing period (in August 2004 and 2005) and the reproductive period (in November 2004 and 2005). Various growth, reproductive parameters and mannitol content of the control and treatment plants were monitored thereafter. Individuals trimmed to 15 cm before the active growing period in August showed reduced growth (maximum mean lengths = 72.76 士 44.11 cm for 2004 treatment; 51.65 士 20.46 cm for 2005 treatment) and delayed reproduction when compared with tagged controls (maximum mean lengths = 178.00 士 48.26 cm for 2004 treatment; 95.57 土 21.01 cm for 2005 treatment). Only about 70% of the plants trimmed in August 2004 and 60% of those trimmed in August 2005 became reproductive in February 2005 and 2006 respectively, compared with 100% of the tagged controls that became reproductive in December 2004 and January 2006. Plants trimmed to 15 cm before the reproductive period in November 2004 and 2005 remained at around 25 cm in length throughout the reproductive period. However, around 45% (2004 treatment) and 50% (2005 / treatment) of them still became reproductive in February 2005 and 2006 respectively / although their sizes were smaller than the minimum reproductive size of 40 cm recorded earlier. Treatment plants displayed lower mannitol content in various parts and they also produced fewer receptacles when compared with the control plants. For plants trimmed down to holdfast, more new shoots emerged from those trimmed in November 2004 and 2005 than from those trimmed in August, suggesting that more reserved resources were available in the holdfast in November, after the plants had gone through rapid growth in autumn. None of these plants however, ever became reproductive. These responses suggested that in the existence of a trade-off between growth and reproduction, differential allocation of resources was adopted by Sargassum siliquastrum, with the ultimate effect of propagating itself through sexual reproduction or vegetative growth. / The results of this study revealed the phenology of Sargassum siliquastrum, its seasonal variation of mannitol content and the strategy for growth and reproduction it adopted when resources were reduced. The ability and flexibility of algae to grow and reproduce under reduced resources or change in environmental conditions using different strategies, with S. siliquastrum as an example, suggested the reasons for their success in the marine environment. All these data and observation provide significant baseline information on how algae, the ecologically important primary producer in the / coastal area would be able to cope, especially in a rapidly changing marine environment like that of Hong Kong or elsewhere in other parts of the world where changes could be taking place at a global scale. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / 生物在它們的生活週期中有著不同時期的生長和繁殖期，從這點可以看出生物將 有限的資源分配到不同的生長過程時，要面對一定程度的取捨。因此在了解生物 如何面對及適應環境轉變的時候，一些有關它們的生活週期、體內資源在不同時 期的分佈情況，以及運用資源的策略的資料亦變得尤其重要。 / 在2004年9月至2006年5月期間，我們進行了每月樣方測量，以紀錄位於東平 洲海岸公園龍落水內裂葉馬尾藻(Sargassum siliquastrum (Turn.) Ag.)的物候 性。我們發現這個物種有四個典型的生長階段：新生期（緩慢生長期）、活躍生 長期、繁殖期及老化期（回枯期）。而這個族群最高的長度（2005年1月的90.28 ±45.13cm; 2006 年 2 月的 70.18 士 18.65cm)、主莖的數量（2005 年 1 月的 2.21 士 0.81條；2005年12月的2.29 土 0.47條）、第一類(l-3cm)新生枝條數量(2005 年 2 月的 6/71 ± 3.05 條；2006 年 1 月的 5.18士 1.39 條）、第二類（>3-5cm)新 生枝條數量（2005年2月的2.53 ± 1.23條）、繁殖比率（2005年的70.59 士 33.08% ； 2006 年的 77.74 士 17.94%)、及繁殖力(2004 年 12 月的 21.13 士 7.59% ； 2006年2月的10.80 ± 7.24%)均出現在冬季，而這些相應參數的最低點則在夏 季出現。相反，對比這個族群在繁殖時期的密度（2005年1月的5 ± 41.33個體 /平方米；2005年12月的23.50 ± 11.00個體/平方米），最高的族群密度則紀錄在 生長較緩慢的夏季（2005年7月的90.50 ± 62.78個體/平方米）。在被鑑定的物理 參數中，由夏季轉到冬季時的低溫及短日照均有助於族群內個體長度及其繁殖器 的生長。 / 在2003年12月到2006年5月期間，我們利用了高效能液相色譜法（High Performance Liquid Chromatography)，來硏究裂葉馬尾藻體內的儲備物質甘露醇 / (Mannitol)的季節性及其在個體內不同部分（包括固著器、植物的底部、中部、 頂部以及繁殖器)的差異。結果顯示，裂葉馬尾藻的甘露醇季節性的含量介乎於 它們乾水重量的1%到17%。當它們進入活躍生長期，甘露醇的含量便會提升， 而最高含量則紀錄在2004年9月的10.81 ± 4.87克甘露醇/100克乾海藻及2005 年10月的13.17 ±5.60克甘露醇/100克乾海藻。當它們在12月間進入繁殖期時， 體內的甘露醇含量便開始下降，在繁殖期間則維持不變。直到繁殖期完結後，此 物種體內的甘露醇含量便大幅度下降。在4月這個緩慢生長期間，我們紀錄到一 個小幅度的甘露醇增長(2004年的5.69 ± 2.11克甘露醇/100克乾海藻；2005年 的5.91 ± 3.71克甘露醇/100克乾海藻；2006年的17.87 ± 7.46克甘露醇/100克乾 海藻）。由此可以看出在緩慢生長期間生產的過剩資源均用在維持多年生的固著 器的生命，或用作發展下一個季節所需的新生枝條。從個體的層面來看，相對植 物上較年青的中部及頂部，較成熟的部分（即固著器及植物的底部）含有較多的 甘露醇。此物種繁殖器的甘露醇含量是最低的，這亦與其較低的光合作用效率吻 合。相反，裂葉馬尾藻的固著器內有很高的甘露醇含量，這與其低光合作用效率 不成比例，相信是因爲甘露醇從植物的底部滲到固著器內。另外，此物種底部所 含的甘露醇與其兩個月後的一些生長參數（例如長度、主莖及新生枝條的數量） 成顯著的正向關聯，這暗示裂葉馬尾藻體在固著器及植物底部內的儲備物質均用 在新生枝條的發展及延長。 / 我們亦利用切除實驗來硏究不同程度的資源減少對裂葉馬尾藻的生長及繁殖的 影響。在此物種的活躍生長期前（2004年及2005年8月）及繁殖期前（2004年 及2005年11月），個別標記樣本上的無性枝條被切除至固著器上方15cm處或被 切除至留下固著器，而各組別內所有標記樣本的長度、生殖狀態及甘露醇含量則 被每月記錄。實驗結果顯示，在八月（活躍生長期前）的實驗中，與對照組別相 比（最高長度爲 2004 年 178.00 士 48.26cm ； 2005 年的 95.57 ± 21.01cm) , 無性枝 / 條被切除至固著器上方15cm處的個體顯示了較緩慢的生長（最高長度爲2004 / 年的72.76 ± 44.11cm ； 2005年的51.65 ± 20.46cm)及延緩的繁殖期。在2004及 2005年8月的實驗中，所有在對照組別內的個體均在2004年12月及2006年1 月進入繁殖期，但無性枝條被切除至固著器上方15cm處的個體中，分別只有70% 和60%的個體在翌年的2月進入繁殖期。相比無性枝條在繁殖期前（2004年及 2005年11月）被切除至固著器上方15cm處的個體的長度，它們在整個繁殖期 中均維持在25cm左右。儘管這些個體的長度遠低於該品種的40cm之最低繁殖 長度，可是當中仍有45% (2004年）及50% (2005年）的個體分別在2005及2006 年的2月進入繁殖期。這些實驗個體的繁殖力及各部分的甘露醇含量均較對照組 別的個體爲低。此外，對比8月及11月時無性枝條被切除至固著器的實驗個體， 後者在固著器所重新長出的葉片均較前者爲低，反映裂葉馬尾藻的固著器在剛過 度了秋季活躍生長期的11月時，內部所集存的資源較8月時爲高。可是，所有 這些重新長出葉片的個體均沒有進入繁殖期。所有實驗個體以上的反應顯示出， 裂葉馬尾藻在生長及繁殖兩者間要面對一定的取捨，因此此物種需要作出有效的 資源分配，以達致其利用有性或無性的繁殖方法來延續後代的最終目標。 / 是次硏究紀錄了裂葉馬尾藻的物候學、其季節性的甘露醇含量，以及此物種在資 源減少的情況下作出的最佳分配策略。這顯示出爲適應環境變化，此物種能有彈 性地改變其生長週期及資源分配策略，這一切均可進一步證明此物種在海洋環境 中佔優的原因。是次硏究所得的數據，均是發展香港藻類保育及管理計劃時所需 的重要基本資料。 / Wong, Suet Ying. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 270-299). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract (English) --- p.iii / Abstract (Chinese) --- p.ix / Contents --- p.xii / List of Tables --- p.xvii / List of Figures --- p.xxi / Chapter Chapter 1 --- General Introduction / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.1.1 --- Life History and Resource Allocation --- p.1 / Chapter 1.1.2 --- Resource Allocation in Plants --- p.3 / Chapter 1.1.3 --- Resource Allocation in Algae --- p.4 / Chapter 1.2 --- Importance of Sargassum Communities --- p.8 / Chapter 1.3 --- Marine Environment and Sargassum Communities in Hong Kong --- p.11 / Chapter 1.4 --- Study Organism --- p.13 / Chapter 1.5 --- General Objectives --- p.15 / Chapter 1.6 --- Study Site --- p.16 / Chapter 1.7 --- Organization of the Thesis --- p.18 / Chapter Chapter 2 --- Phenology of Sargassum siliquastrum / Chapter 2.1 --- Introduction --- p.23 / Chapter 2.2 --- Materials and Methods --- p.29 / Chapter 2.2.1 --- "Seasonal Change in Size, Number of Main Axes, Number of New Shoots, Density and Population Structure" --- p.29 / Chapter 2.2.2 --- Percentage of Reproductive Individuals --- p.30 / Chapter 2.2.3 --- Seasonal Change in Biomass and Reproductive Effort (RE) of Sampled Individuals --- p.31 / Chapter 2.2.4 --- Seasonal Change in Physical Parameters --- p.32 / Chapter 2.2.5 --- Statistical Analysis --- p.33 / Chapter 2.3 --- Results --- p.34 / Chapter 2.3.1 --- "Seasonal Trend in Size, Number of Main Axes and Number of New Shoots in the Population" --- p.34 / Chapter 2.3.2 --- Seasonal Trend in Mean Density and Population Structure --- p.37 / Chapter 2.3.3 --- Seasonal Change in Dry Weight of Sampled Individuals --- p.39 / Chapter 2.3.4 --- Reproductive Phenology --- p.41 / Chapter 2.3.5 --- Seasonal Trends of Physical Parameters and Their Correlation with Growth and Reproduction of the Populations --- p.43 / Chapter 2.4 --- Discussion --- p.45 / Chapter 2.4.1 --- The Global Trend of Seasonality of Sargassum --- p.45 / Chapter 2.4.2 --- Annual Growth Cycle of Sargassum siliquastrum Population --- p.47 / Chapter 2.4.3 --- Growth Seasonality of Sargassum siliquastrum --- p.49 / Chapter 2.4.4 --- Reproductive Seasonality of Sargassum siliquastrum --- p.53 / Chapter 2.4.5 --- Population Decline of Sargassum siliquastrum in Lung Lok Shui --- p.55 / Chapter 2.5 --- Summary --- p.58 / Chapter Chapter 3 --- Mannitol Content in Sargassum siliquastrum / Chapter 3.1 --- Introduction --- p.76 / Chapter 3.2 --- Materials and Methods --- p.85 / Chapter 3.2.1 --- Sample Collection and Preparation --- p.85 / Chapter 3.2.2 --- Extraction of Mannitol from Sargassum siliquastrum --- p.87 / Chapter 3.2.3 --- Determination of Mannitol extracted from Sargassum siliquastrum --- p.87 / Chapter 3.2.4 --- Statistical Analysis --- p.89 / Chapter 3.3 --- Results --- p.90 / Chapter 3.3.1 --- Seasonal Trend of Mean Mannitol Content and Dry Weight in Different Parts of Sargassum siliquastrum --- p.90 / Chapter 3.3.2 --- "Correlation of Mannitol Content in Various Parts with Length, Number of Main Axes and Number of New Shoots in the Population" --- p.99 / Chapter 3.3.3 --- Mannitol Content in Reproductive and Non-reproductive Individuals --- p.100 / Chapter 3.4 --- Discussion --- p.101 / Chapter 3.4.1 --- Seasonal Variation of Mannitol Content in Sargassum siliquastrum --- p.101 / Chapter 3.4.2 --- Vertical Distribution of Mannitol in Sargassum siliquastrum --- p.105 / Chapter 3.4.3 --- Mannitol for Growth and Reproduction in Sargassum siliquastrum --- p.108 / Chapter 3.5 --- Summary --- p.111 / Chapter Chapter 4 --- Effect of Reduced Resources on Growth or Reproduction of Sargassum siliquastrum / Chapter 4.1 --- Introduction --- p.135 / Chapter 4.2 --- Materials and Methods --- p.141 / Chapter 4.2.1 --- Effect of Reduced Resources on Growth of Sargassum siliquastrum --- p.141 / Chapter 4.2.2 --- Effect of Reduced Resources on Reproduction of Sargassum siliquastrum --- p.142 / Chapter 4.2.3 --- Mannitol Content and Reproductive Effort of Treatment Plants of Sargassum siliquastrum --- p.143 / Chapter 4.2.4 --- Statistical Analysis --- p.145 / Chapter 4.3 --- Results --- p.146 / Chapter 4.3.1 --- Responses of Treatment Plants of Sargassum siliquastrum Trimmed before Active Growth Period --- p.146 / Chapter 4.3.1.1 --- Growth of the Control and Treatment Plants --- p.146 / Chapter 4.3.1.2 --- Reproduction of the Control and Treatment Plants --- p.155 / Chapter 4.3.1.3 --- Survival of the Control and Treatment Plants --- p.157 / Chapter 4.3.1.4 --- Mannitol Content of the Treatment Plants --- p.159 / Chapter 4.3.2 --- Responses of Treatment Plants of Sargassum siliquastrum Trimmed before Reproductive Period --- p.164 / Chapter 4.3.2.1 --- Growth of the Control and Treatment Plants --- p.164 / Chapter 4.3.2.2 --- Reproduction of the Control and Treatment Plants --- p.172 / Chapter 4.3.2.3 --- Survival of the Control and Treatment Plants --- p.174 / Chapter 4.3.2.4 --- Mannitol Content of the Treatment Plants --- p.176 / Chapter 4.4 --- Discussion --- p.179 / Chapter 4.4.1 --- Effect of Trimming on the Growth of Sargassum siliquastrum --- p.179 / Chapter 4.4.2 --- Effect of Trimming on Reproduction of Sargassum siliquastrum --- p.185 / Chapter 4.4.3 --- Resource Allocation Pattern in Sargassum siliquastrum --- p.190 / Chapter 4.5 --- Summary --- p.194 / Chapter Chapter 5 --- Summary and Conclusion --- p.262 / References --- p.270

Thesis (Ph. D.)--University of Wisconsin--Madison, 1926. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 49-52).

Cheang Chi-chiu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 126-136). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgements --- p.vi / Contents --- p.viii / List of Tables --- p.xi / List of Figures --- p.xiii / Chapter CHAPTER 1: --- Introduction and Background --- p.1 / Chapter 1.1 --- Ecology and distribution of the genus Sargassum --- p.1 / Chapter 1.2 --- Classical taxonomy of the genus Sargassum and associated problems --- p.2 / Chapter 1.3 --- Recent approaches on taxonomic studies of Sargassum --- p.4 / Chapter 1.3.1 --- Morphological studies --- p.4 / Chapter 1.3.2 --- Genetic studies --- p.5 / Chapter 1.3.3 --- Integration of genetic and morphological studies --- p.7 / Chapter 1.4 --- Phylogeographic distribution and population dispersal --- p.8 / Chapter 1.5 --- Description of species --- p.11 / Chapter 1.6 --- Objectives --- p.14 / Chapter 1.7 --- Layout of the thesis --- p.15 / Chapter CHAPTER 2: --- Morphological Examination on Sargassum hemiphyllum --- p.17 / Chapter 2.1 --- Introduction --- p.17 / Chapter 2.2 --- Methodology --- p.18 / Chapter 2.2.1 --- Sampling locations and treatment of specimens --- p.18 / Chapter 2.2.2 --- Morphological measurement --- p.22 / Chapter 2.2.3 --- Data analysis and statistical tests --- p.28 / Chapter 2.3 --- Results --- p.31 / Chapter 2.3.1 --- Choosing parameters from preliminary results --- p.31 / Chapter 2.3.2 --- Analysis on the main data set --- p.40 / Chapter 2.3.2.1 --- Layout of the data set --- p.40 / Chapter 2.3.2.2 --- Spatially conservable vs. variable parameters --- p.51 / Chapter 2.3.3 --- Conservable morphological parameters- consensus of specimens --- p.58 / Chapter 2.3.4 --- Variable morphological parameters- variation among specimens based on categorical parameters --- p.58 / Chapter 2.3.5 --- Differentiation of populations based on measurable and numerical parameters --- p.63 / Chapter 2.4 --- Discussion --- p.74 / Chapter 2.4.1 --- Temporal vs. spatial variation in the morphology of Sargassum hemiphyllum --- p.74 / Chapter 2.4.2 --- Spatially conservable characters for the taxonomic identification of Sargassum hemiphyllum --- p.77 / Chapter 2.4.3 --- Variation within Sargassum hemiphyllum --- p.77 / Chapter 2.4.4 --- Variation along the biogeographical gradient --- p.79 / Chapter CHAPTER 3: --- Genetic Analysis of RbcL-S Spacer in Sargassum hemiphyllum --- p.82 / Chapter 3.1 --- Introduction --- p.82 / Chapter 3.2 --- Methodology --- p.87 / Chapter 3.2.1 --- Extraction and purification of DNA --- p.87 / Chapter 3.2.2 --- Polymerase chain reaction (PCR) and gel electrophoresis --- p.87 / Chapter 3.2.3 --- Purification of PCR product --- p.90 / Chapter 3.2.4 --- DNA sequencing --- p.90 / Chapter 3.2.5 --- RFLP study --- p.92 / Chapter 3.2.6 --- Sequence alignment and analysis --- p.92 / Chapter 3.3 --- Results --- p.93 / Chapter 3.3.1 --- Extraction and PCR amplification --- p.93 / Chapter 3.3.2 --- Pilot study --- p.97 / Chapter 3.3.3 --- RFLP study --- p.103 / Chapter 3.4 --- Discussion --- p.108 / Chapter 3.4.1 --- Suitability of RbcL-S spacer as genetic marker at population level --- p.108 / Chapter 3.4.2 --- Two clades vs. two varieties of S. hemiphyllum --- p.109 / Chapter 3.4.3 --- Reproductive barrier --- p.110 / Chapter CHAPTER 4: --- General Discussion --- p.113 / Chapter 4.1 --- Morphological and genetic data- consistence or conflict --- p.113 / Chapter 4.2 --- Latitudinal gradient of seawater temperature in the Pacific NW --- p.115 / Chapter 4.3 --- Fluctuation in seawater salinity in the Pacific NW --- p.118 / Chapter 4.4 --- Possible initiation of speciation --- p.122 / Chapter 4.5 --- Works to be done in the future --- p.123 / References --- p.126

由於東南亞擁有複雜的地質歷史及海洋環境，因此生物多樣性尤其豐富。在更新世時期(Pleistocene)，海平面波動導致淺水域的陸地暴露, 繼而造成海洋盆地的分隔。在末次盛冰期(Last Glacial Maximum)，最低海平面甚至低於現今的水平120米。當時大量的土地暴露於海平面上，最大的連接加里曼丹（婆羅洲），蘇門答臘和爪哇，稱為巽他陸架(Sunda Shelf)。巽他陸架不單隔開了南中國海，西里伯斯海和蘇祿海，更分隔了印度洋和太平洋。當海平面上升，巽他陸架逐漸被海水覆蓋，附近的海洋生物於是重新佔領為淒息地。因此物種的散播和混合相信是造成東南亞地區豐富生物多樣性的原因。 / 親緣地理研究顯示，巽他陸架的出現顯著地塑造了海洋動物的基因格局(genetic pattern)。其中最突出的，是在印尼東部（西里伯斯海和弗洛雷斯海）和印尼西部（爪哇海）的動物樣本發現了明顯的基因分別。另一方面，由於海洋動物大部分都有浮游幼蟲階段，促進了遺傳的連繫(genetic connectivity)。然而，大部份的親緣地理研究都針對海洋動物，而缺乏對其他生物（例如植物及藻類）的知識。廣泛分佈於東南亞沿海海域的大型藻類馬尾藻屬(Sargassum spp.) ，有著獨特的生命史。它們有著固定的繁殖幼體(germlings)，而那些繁殖幼體卻可以依附在浮藻體(drifting fronds)上經海流傳播。這特點使它們成為一個很好的研究對象，並提供不同的視角了解該地區的親緣地理學和進化史。本論文選擇了三種在本地區最常見和分佈最廣的品種作研究，分別為匍枝馬尾藻(S. polycystum)，硬葉馬尾藻(S. aquifolium)和冬青葉馬尾藻(S. ilicifolium)。這些物種的種群結構預計會同時受到過去的地理隔離(vicariance event)和現今的海洋環流的影響。因此本研究用了三個分子標記，分別為細胞核內第二內轉錄間隔區(ITS2)，葉綠體染色體內的雙磷酸核酮糖羧化脢大小單位的間隔序列區(RuBisCo spacer)和線粒體細胞色素c氧化酶亞基-III(cytochrome oxidase subunit-III)來分析它們的種群結構。 / 研究揭示了冬青葉馬尾藻(S. ilicifolium)的種群可分為四個分支：西爪哇，南中國海，西里伯斯海/弗洛雷斯海和澳大利亞/太平洋群島，這相信是過去冰川分離的結果。這些分支重新佔領巽他陸架地區後產生了單型(haplotype)的混合。相反，匍枝馬尾藻(S. polycystum)和硬葉馬尾藻(S. aquifolium)在基因上比較同質並找不到分支。它們種群結構上的差異是由於不同的繁殖方式：冬青葉馬尾藻(S. ilicifolium)是季節性繁殖的，所以它的傳播很依賴於季候風洋流的方向；然而硬葉馬尾藻(S. aquifolium)則可以全年繁殖，這特性促進了它的傳播和基因的連繫；最後，匍枝馬尾藻(S. polycystum)能夠無性繁殖，這解釋到它相對較低的遺傳多樣性(genetic diversity)。 / 此研究首次透過東南亞馬尾藻的比較親緣地理發現不同的繁殖方式造成了種群結構的差異，並藉此提供了另一種機制來解釋該地區的進化歷史。 / Southeast Asia is well-known for its high biodiversity which is largely due to its complex geological history and present day oceanographic conditions. Fluctuating sea level during the Pleistocene resulted in exposure of land masses in relatively shallow water and isolation of marine basins. The lowest sea level at Last Glacial Maximum was 120m below present day level. This exposed a large land mass known as the Sunda Shelf which connected Kalimantan (Borneo), Sumatra and Java. South China Sea, Celebes Sea and Sulu Sea were isolated from each other while Indian Ocean was separated from Pacific Ocean. After rising of sea level, recolonization to Sunda Shelf region occurred. Population dispersal and mixing may have contributed to cause high biodiversity in the region. / Previous phylogeographical studies revealed significant genetic pattern of marine animals shaped by the emergence of Sunda Shelf. The most prominent of these was the isolation between Eastern (Celebes Sea and Flores Sea) and Western Indonesia (Java Sea). On the other hand, present oceanographic conditions also facilitated genetic connectivity among marine animals as most of them have pelagic larval stages. Most of the phylogeographical studies, however, were on marine animals. Marine macroalgae, in particular members of the genus Sargassum, are widely distributed in the coastal seas of Southeast Asia. Their unique life history patterns and restricted dispersal ability due to their immobile germlings on one hand, and unique dispersal strategy on the other hand with germlings attached on floating fronds that can be drifted by ocean currents, make them a good candidate to provide a different perspective in understanding the phylogeography and the evolutionary history of the region. Three species of Sargassum, S. polycystum, S. aquifolium and S. ilicifolium were chosen for study. They are the most common and most widely distributed canopy species in Southeast Asia. The population structures of these species were expected to be subjected to the influence of both the vicariant events in the past and the present day oceanographic circulation. Three molecular markers were used to assess the presence of any population structure, namely the nuclear Internal Transcribed Spacer 2 (ITS2), plastidal RuBisCo spacer (Rbc spacer) and mitochondrial cytochrome oxidase subunit-III (Cox3). / Significant structure was revealed in populations of S. ilicifolium, which could be divided into four clades: West Java, South China Sea, Celebes/Flores Sea and Australia/Pacific Islands as the result of past glacial isolation. Recolonization to Sunda Shelf occurred with admixture of haplotypes from adjacent clades. In constrast, homogeneous population was revealed in S. polycystum and in Southeast Asian population of S. aquifolium. The difference in population structure between these three species may be explained by differences in their modes of reproduction. Sargassum ilicifolium exhibits seasonal reproduction and its dispersal was highly dependent on direction of monsoon currents. On the other hand, S. aquifolium reproduces throughout the whole year which may facilitate its dispersal and genetic connectivity within Southeast Asia. Finally, S. polycystum can propagate asexually. This could have contributed to its low genetic diversity across its wide distribution range. / The present research provided the first comprehensive examination of comparative phylogeography of macroalgae in Southeast Asia with mode of reproduction found to be an important factor that significantly contributed to the structure of Sargassum populations. This study thus provided another likely mechanism to explain the evolutionary history of the region, as exemplified by the large genus Sargassum. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Chan, Sze Wai. / Thesis (Ph.D.) Chinese University of Hong Kong, 2014. / Includes bibliographical references (leaves 126-138). / Abstracts also in Chinese.

Thesis (Ph. D.)--University of Chicago, Dept. of Ecology and Evolution, Dec. 2003. / Includes bibliographical references. Also available on the Internet.

Foram feitas comparações na composição da fauna vágil de duas praias de intensidades de ondas diferentes. Coletas mensais da amostra de alga foram feitas durante o período de julho/74 a junho/75 na Praia do Lamberto (abrigada) e Praia Grande (exposta). Foi dada mais ênfase aos Gammaridea por serem dominantes - dentre 26 taxa coletados. Foram discutidas as relações entre as algas e estes Crustacea. Estudos do aspecto morfológico mostraram que algumas espécies de Gammaridea estão mais adaptadas na praia agitada e outras na protegida. Na Praia Grande algumas espécies tiveram suas maiores freqüências na primavera e verão e na Praia do Lamberto elas se deram em épocas diferentes. Baseando-se na diversidade de espécies e na similaridade média encon-trada para os Gammaridea, parece não haver diferenças marcantes entre os dois pontos de coleta. / The mobile C. Agardh, fauna of Sargassum cymosum 1820 of \"Praia do Lamberto\" and \"Praia Grande\", Ubatuba, São Paulo, with special reerence to Gammaridea (Crustacea - Amphypoda) A comparative study on the composition of the mobile fauna associated to Sargassum cymosum from two localities, one sheltered (Praia do Lamberto) and another exposed (Praia Grande) has been made. Samples of the algae were collected monthly from July/1974 to June/1975. Gammaridea was dominant arnong. 26 collected taxa. The relationship between algae and Gammaridea is discussed. The study of the orphological aspects of this Crustacea showed that some species seem to be more adapted to living in sheltered locality and others in exposed ones. The species had their highest frequency in different seasons at both localities. The diversity of species and medium similarity of Gammaridea showed that no conspicuous differences between the two localities occur.

Foram feitas comparações na composição da fauna vágil de duas praias de intensidades de ondas diferentes. Coletas mensais da amostra de alga foram feitas durante o período de julho/74 a junho/75 na Praia do Lamberto (abrigada) e Praia Grande (exposta). Foi dada mais ênfase aos Gammaridea por serem dominantes - dentre 26 taxa coletados. Foram discutidas as relações entre as algas e estes Crustacea. Estudos do aspecto morfológico mostraram que algumas espécies de Gammaridea estão mais adaptadas na praia agitada e outras na protegida. Na Praia Grande algumas espécies tiveram suas maiores freqüências na primavera e verão e na Praia do Lamberto elas se deram em épocas diferentes. Baseando-se na diversidade de espécies e na similaridade média encon-trada para os Gammaridea, parece não haver diferenças marcantes entre os dois pontos de coleta. / The mobile C. Agardh, fauna of Sargassum cymosum 1820 of \"Praia do Lamberto\" and \"Praia Grande\", Ubatuba, São Paulo, with special reerence to Gammaridea (Crustacea - Amphypoda) A comparative study on the composition of the mobile fauna associated to Sargassum cymosum from two localities, one sheltered (Praia do Lamberto) and another exposed (Praia Grande) has been made. Samples of the algae were collected monthly from July/1974 to June/1975. Gammaridea was dominant arnong. 26 collected taxa. The relationship between algae and Gammaridea is discussed. The study of the orphological aspects of this Crustacea showed that some species seem to be more adapted to living in sheltered locality and others in exposed ones. The species had their highest frequency in different seasons at both localities. The diversity of species and medium similarity of Gammaridea showed that no conspicuous differences between the two localities occur.