據稿本影印 / 論文(哲學碩士)--香港中文大學硏究院地理學部,1993. / 參考文獻: leaves 212-219 / 郭錦添. / Chapter I. --- 導論 / Chapter A. --- 引言 --- p.1 / Chapter B. --- 研究目的 --- p.1 / Chapter C. --- 研究意義 --- p.3 / Chapter D. --- 理論架構 --- p.4 / Chapter 1. --- 化學形態 --- p.4 / Chapter a. --- 水體中重金屬化學形態分類 --- p.6 / Chapter b. --- 顆粒態重金屬化學形態分類 --- p.7 / Chapter 2. --- 重金屬化學形態與其毒性的關係 --- p.10 / Chapter 3. --- 化學形態分析方法及其困難 --- p.13 / Chapter 4. --- 重金屬在水體與沉積物交接面間的活動 --- p.15 / Chapter 5. --- 重金屬遷移與形態間轉化機制 --- p.17 / Chapter E. --- 香港過往對海港中重金屬的研究 --- p.19 / Chapter II. --- 研究方法 / Chapter A. --- 研究策略 --- p.22 / Chapter B. --- 採樣點分佈 --- p.23 / Chapter C. --- 野外採樣方法 --- p.25 / Chapter D. --- 分析項目及方法 --- p.26 / Chapter 1. --- 重金屬的選擇 --- p.26 / Chapter a. --- 毒性 --- p.26 / Chapter b. --- 濃度 --- p.27 / Chapter c. --- 參考數據 --- p.27 / Chapter 2. --- 分離技術和分析方法 --- p.28 / Chapter a. --- 重金屬分祈法 --- p.28 / Chapter b. --- 水樣分析法 --- p.30 / Chapter c. --- 沉積物樣本分析法 --- p.31 / Chapter d. --- 試劑配備 --- p.32 / Chapter e. --- 選擇以上分析項目的原因 --- p.33 / Chapter f. --- 模擬實驗的設計 --- p.34 / Chapter III. --- 香港近岸沉積物中重金屬含量及其化學形態分佈 / Chapter A. --- 引言 --- p.39 / Chapter B. --- 總濃度分析 --- p.39 / Chapter C. --- 化學形態分析 --- p.40 / Chapter D. --- 總結 --- p.44 / Chapter IV. --- 荃灣個案研究 / Chapter A. --- 研究目的及其重要性 --- p.45 / Chapter B. --- 研究结果 --- p.46 / Chapter 1. --- 水質 --- p.46 / Chapter a. --- 荃灣海域的水文情況 --- p.46 / Chapter b. --- 水污染的空間與時間分佈規律 --- p.48 / Chapter c. --- 水體中重金屬污染物的濃度與存在形態 --- p.49 / Chapter d. --- 小结 --- p.50 / Chapter 2. --- 海底沉積物 --- p.51 / Chapter a. --- 荃灣海域底泥的化學特性 --- p.51 / Chapter b. --- 荃灣海泥中重金屬的存在化學形態 --- p.52 / Chapter C. --- 討論 --- p.54 / Chapter D. --- 從個案研究看全港重金屬污染（沉降）特性 --- p.55 / Chapter V. --- 模擬實驗 / Chapter A. --- 引言 --- p.57 / Chapter B. --- 沉降反應模擬實驗的設計及目的 --- p.57 / Chapter 1. --- 形態轉化模擬 --- p.57 / Chapter 2. --- 沉降模擬 --- p.56 / Chapter 3. --- 渠口反應模擬 --- p.58 / Chapter C. --- 釋放模擬實驗的設計及目的 --- p.59 / Chapter 1. --- 疏浚模擬 --- p.59 / Chapter 2. --- 棄置模擬 --- p.60 / Chapter 3. --- 氧化模擬 --- p.60 / Chapter 4. --- 降雨模擬 --- p.60 / Chapter D. --- 實驗條件 --- p.61 / Chapter E. --- 沉降模擬實驗结果 --- p.66 / Chapter 1. --- 形態轉化模擬實驗结果 --- p.66 / Chapter 2. --- 沉降實驗结果 --- p.68 / Chapter 3. --- 渠口反應模擬實驗结果 --- p.70 / Chapter 4. --- 沉降模擬實驗结論 --- p.79 / Chapter F. --- 釋放模擬實驗结果 --- p.80 / Chapter 1. --- 疏浚模擬實驗结果 --- p.81 / Chapter 2. --- 棄置模擬實驗結果 --- p.82 / Chapter 3. --- 氧化模擬實驗结果 --- p.88 / Chapter 4. --- 降雨模擬實驗结果 --- p.90 / Chapter 5. --- 釋放模擬實驗结論 --- p.91 / Chapter VI. --- 討論 / Chapter A. --- 本港海域的重金屬存在形態與其活動性及毒性的關係 --- p.93 / Chapter B. --- 現存於本港海泥中重金屬形態分佈的形成機制和遷移條件 --- p.95 / Chapter 1. --- 形態分佈的形成機制 --- p.95 / Chapter 2. --- 遷移條件 --- p.96 / Chapter C. --- "環境管理-水質管制,疏浚和填海等工程對底泥中重金屬的影響" --- p.97 / Chapter D. --- 海泥中重金屬污染的空間分佈特性（擴散模型） --- p.98 / Chapter E. --- 總结 --- p.99 / Chapter VII. --- 结論 / Chapter A. --- 總结研究结果 --- p.101 / Chapter B. --- 研究中某些較特別的發現 --- p.104 / Chapter C. --- 研究的局限與展望 --- p.105

Both instantaneous current and chemical propagation predictions are of utmost importance for all littoral naval operations, including diving, amphibious and mine warfare ones. Undoubtedly, the operating limits and environmental thresholds are crucial and highly reliant on the accuracy and precision of the predictions. San Diego Bay is important because it hosts a large part of the U.S. fleet and has special ecological significance. A hydrodynamic model, "Water Quality Management and Analysis Package" (WQMAP), is used to predict the instantaneous currents with various forcing functions (tides, winds, and lateral boundary fluxes) and a hydrochemical model, "Chemical Management and Analysis Package", (CHEMMAP) to predict the water contamination and to simulate chemical attacks/accidents in San Diego Bay, which raise considerations regarding public health, economy, ecology or even national security. The study shows the barotropic nature of San Diego Bay, the slight significance of wind and the vulnerability of a semi-enclosed tidal basin in a possible chemical attack or accident. Simultaneously, it evaluates and uses two models used by NAVOCEANO. / Hellenic Navy author.

Our understanding of the global marine xed nitrogen budget has undergone rapid growth, and as a result there is debate as to whether or not it is balanced. The Arctic plays a disproportionately large role in the sink terms of this budget. This paper works to understand the role of the Canada Basin in the nitrogen cycle. We utilize two tracers of denitri cation: N2/Ar, a dissolved gas tracer, and N*, a nutrient ratio tracer. We aim to quantify the current state of nitrogen cycling in the Canada Basin, and determine its role in the global cycle. Our paired tracer method provides support for shelf denitri cation rates while providing an estimate of ventilation in the same water mass, and provides an estimate for deep benthic denitri cation rates. We observe a disconnect between N2/Ar and N* in the Paci c Upper Halocline Layer (PUHL), wherein the excess N2/Ar we expect from N* is nearly 250% larger than the excess we observe. Our calculations suggest that an approximate steady state between benthic denitri cation and gas exchange on the Chukchi shelf maintains this disconnect. Our measurements of the PUHL support the shelf denitri cation rates reported from direct measurements, and can predict wind speeds required for ventilation within a factor of two. A 1D diffusion model of the old deep waters of the Canada Basin supports benthic denitri cation rates of 0.095-0.15 Tg N y-1. Benthic denitri cation rates determined from the model are on the low end of rates in other deep basins. Our results suggest additional measurements of these tracers in the Canada Basin and surrounding areas would help to constrain both the physical and biological processes controlling nitrogen cycling. / Graduate / 0425 / jen.l.reeve@gmail.com

Thesis (Ph. D.)--Joint Program in Oceanography, Massachusetts Institute of Technology/Woods Hole Oceanographic Institution, 1997. / Includes bibliographical references. / by Örjan Gustafsson. / Ph.D.

Thesis (Ph. D.)--Joint Program in Chemical Oceanography (Massachusetts Institute of Technology, Dept. of Earth, Atmospheric and Planetary Sciences; and the Woods Hole Oceanographic Institution), 1999. / Includes bibliographical references. / The goal of this thesis was to use high resolution analytical techniques coupled with molecular level analyses to chemically characterize high molecular weight (> 1 k Da (HMW)) dissolved organic matter (DOM) isolated from seawater in an attempt to provide new insights in to the cycling of DOM in the ocean. While a variety of sites spanning different environments (fluvial, coastal and oceanic) and ocean basins were examined, the chemical structure of the isolated HMW DOM varied little at both the polymer and monomer levels. All samples show similar ratios of carbohydrate:acetate:lipid carbon (80±4:10±2:9±4) indicating that these biochemicals are present within a family of related polymers. The carbohydrate fraction shows a characteristic distribution of seven major neutral monosaccharides: rhamnose, fucose, arabinose, xylose, mannose, glucose and galactose; and additionally contains Nacetylated amino sugars as seen by Nuclear Magnetic Resonance Spectroscopy (NMR). This family of compounds, consisting of a specifically linked polysaccharide backbone that is acylated at several positions, has been termed acylated polysaccharides (APS) by our laboratory. APS accounts for 50% of the carbon in HMW DOM isolated from the surface ocean and 20% of the carbon in HMW DOM isolated from the deep ocean. In order to identify a possible source for APS three species of phytoplankton, Thalassiossira weissflogii, Emiliania huxleyi and Phaeocystis, were cultured in seawater and their HMW DOM exudates examined by variety of analytical techniques. Both the T. weissflogii and E. huxleyi exudates contain compounds that resemble APS indicating that phytoplankton are indeed a source of APS to the marine environment. Furthermore, the degradation of the T. weissflogii exudate by a natural assemblage of microorganisms indicates that the component resembling APS is more resistant to microbial degradation compared to other polysaccharides present in the culture. Molecular level analyses show the distribution of monosaccharides to be conservative in surface and deep waters suggesting that APS is present throughout the water column. In order to determine the mechanism by which APS is delivered to the deep ocean the [delta]14C value of APS in the deep ocean was compared to the A14C value of the dissolved inorganic carbon (DIC) at the same depth. If the formation of deep water is the dominant mode of transport then both the DIC and APS will have similar [delta]14C values. However, if APS is injected into the deep ocean from particles or marine snow then the [delta]14C value of APS will be higher than the DIC at the same depth. Our results indicate that APS in the deep Pacific Ocean carries a modem [delta]14C value and is substantially enriched in 14C relative to the total HMW DOM and the DIC at that depth. Thus, particle dissolution appears to be the most important pathway for the delivery of APS to the deep ocean. / by Lihini I. Aluwihare. / Ph.D.

Graduation date: 1997

The functional group composition of acid polysaccharides was determined after isolation using cross-flow ultrafiltration, radiolabeling with 234Th(IV) and other isotopes, and separation using isoelectric focusing (IEF) and polyacrylamide gel electrophoresis (PAGE). Phosphate and sulphate concentrations were determined from cultured bacterial and phytoplankton colloid, particulate and colloidal samples collected from the Gulf of M??xico (GOM). Characterization of the 234Th(IV)-binding biomolecule was performed using ion chromatography (IC), and gas chromatography-mass spectrometry (GC-MS). Radiotracer experiments and culture experiments were conducted in determining the binding environment of the 234Th(IV)-binding ligand (i.e., sorption onto suspended particles), as well as the origin of the ligand in seawater systems. In all samples, 234Th(IV) isoelectric focusing profiles indicated that 49% to 65% of the 234Th(IV) labeled EPS from Roseobacter gallaeciensis, Sagittula stellata, Emiliania huxleyi, Synechococcus elongatus and GOM Station 4-72m was found at a pHIEF of 2 in the IEF spectrum. The carboxylic acid group appeared at the same pHIEF as 234Th(IV) for EPS from Roseobacter gallaeciensis, Emiliania huxleyi, Synechococcus elongatus and GOM colloidal organic matter sample. The phosphate group appeared at the same pHIEF as 234Th(IV) for EPS from Roseobacter gallaeciensis, and Synechococcus elongatus sample. The sulphate group was found at the same pHIEF as 234Th(IV) for EPS from S. elongatus and GOM colloidal organic matter sample. The total polysaccharide content was only 14% and 8%, uronic acids were approximately 5.4% and 87.1%, and total protein content was 2.6% and 6.2% of total carbon content of Sagittula stellata and Synechococcus elongatus, respectively. Monosaccharides identified in both Sagittula stellata and Synechococcus elongatus were galactose, glucose, and xylose in common. In addition, Sagittula stellata contained mannose and Synechococcus elongatus had galactoglucuronic acid. Thus, depending on the species, the size, structural composition, and functional groups of the 234Th(IV)-binding, acidic polysaccharides will vary. From these observations, it is concluded that the steric environment and not necessarily the exact functional group might actually be responsible for thorium-234 complexation to macromolecular organic matter. This research helped to improve our understanding of the observed variability in POC/234Th ratios in the ocean and provided insights into factors that regulate organic carbon export fluxes.

The functional group composition of acid polysaccharides was determined after isolation using cross-flow ultrafiltration, radiolabeling with 234Th(IV) and other isotopes, and separation using isoelectric focusing (IEF) and polyacrylamide gel electrophoresis (PAGE). Phosphate and sulphate concentrations were determined from cultured bacterial and phytoplankton colloid, particulate and colloidal samples collected from the Gulf of M??xico (GOM). Characterization of the 234Th(IV)-binding biomolecule was performed using ion chromatography (IC), and gas chromatography-mass spectrometry (GC-MS). Radiotracer experiments and culture experiments were conducted in determining the binding environment of the 234Th(IV)-binding ligand (i.e., sorption onto suspended particles), as well as the origin of the ligand in seawater systems. In all samples, 234Th(IV) isoelectric focusing profiles indicated that 49% to 65% of the 234Th(IV) labeled EPS from Roseobacter gallaeciensis, Sagittula stellata, Emiliania huxleyi, Synechococcus elongatus and GOM Station 4-72m was found at a pHIEF of 2 in the IEF spectrum. The carboxylic acid group appeared at the same pHIEF as 234Th(IV) for EPS from Roseobacter gallaeciensis, Emiliania huxleyi, Synechococcus elongatus and GOM colloidal organic matter sample. The phosphate group appeared at the same pHIEF as 234Th(IV) for EPS from Roseobacter gallaeciensis, and Synechococcus elongatus sample. The sulphate group was found at the same pHIEF as 234Th(IV) for EPS from S. elongatus and GOM colloidal organic matter sample. The total polysaccharide content was only 14% and 8%, uronic acids were approximately 5.4% and 87.1%, and total protein content was 2.6% and 6.2% of total carbon content of Sagittula stellata and Synechococcus elongatus, respectively. Monosaccharides identified in both Sagittula stellata and Synechococcus elongatus were galactose, glucose, and xylose in common. In addition, Sagittula stellata contained mannose and Synechococcus elongatus had galactoglucuronic acid. Thus, depending on the species, the size, structural composition, and functional groups of the 234Th(IV)-binding, acidic polysaccharides will vary. From these observations, it is concluded that the steric environment and not necessarily the exact functional group might actually be responsible for thorium-234 complexation to macromolecular organic matter. This research helped to improve our understanding of the observed variability in POC/234Th ratios in the ocean and provided insights into factors that regulate organic carbon export fluxes.

Thesis--Woods Hole Oceanographic Institution. / "Technical report." Grant 04-7-158-44104 and 04-8-M01-149. Includes bibliographical references (p. 260-271).

The purpose of this study is to present the results of mineralogical and petrochemical analyses of the solid phase components and the inorganic chemistry of the interstitial waters of the Recent anoxic sediments of Kaneohe Bay, Oahu. Nineteen shallow 1-4 meter gravity cores of the lagoonal sediments of Kaneohe Bay were analyzed for pore water chemistry and seven were subjected to detailed mineralogical and petrochemical analyses. The pore waters of the sediment column show depletions in dissolved SO =4, Ca++, Mg++ and Sr++ accompanied by increases in titration alkalinity, NH4 + , PO 4 -3 and Si02 with respect to the overlying seawater with increasing subbottom depth. Na+, Cl-, K+ and Fetot exhibit minor departures from overlying bay waters assuming that depletions of Na+ and Cl- are the result of an influx of meteoric ground water from beneath the bay's floor. The bay may be divided into two parts on the basis of the rates of pore water diagenesis: in the southern part of the bay, S0 =4 is completely depleted within 80cm subbottom depth, whereas in the northern part, complete S0 =4 reduction does not occur at depths to 350cm. The southern sediments are contaminated by raw, high C/N sewage, resulting in an increased metabolic reduction rate of S0 =4 by anerobic bacteria over that observed in the unpolluted northern bay. Calculation of S0 =4 consumed versus alkalinity plus NH=4 produced indicates a relationship in which roughly one-half of the "produced alkalinity" has been consumed in the formation of authigenic minerals, primarily nontronite and aragonite. Quantitative mineralogical and petrochemical analyses of the solid phase components reveal the loss of amorphous iron-oxyhydroxides, biogenic opaline silica, and amorphous aluminosilicate with increasing subbottom depth. Pyrite formation occurs immediately below the sedimentwater interface. Scanning Electron Microscope observations show a hierarchy of morphologies with depth: single l-micron crystals to 30- micron diameter framboids. Pyrite formation accounts for the lack of detectable S= within the pore waters and is dependent on the availability of pore water iron derived from the dissolution of amorphous iron-oxyhydroxides. The amount of pyrite present below 40cm subbottom depth exceeds the amount which could be formed by the complete reduction of buried pore water S0=4 suggesting the importance of bioturbation in the mixing of pore and overlying seawaters. Authigenic nontronite and mixed-layer smectite-illite are being formed as the result of the reaction of amorphous aluminosilicate with pore water Si02 from opal dissolution and pore water Fe and/or other cations. In those cores where sufficent dissolved iron exists in the pore water, nontronite forms, whereas when dissolved iron is not present as evidenced by the presence of dissolved S= in the pore water, a mixed-layer smectite-illite is formed. The amount of smectite formed is limited by the amount of opal which dissolves. For Kaneohe Bay sediments an average of 0.12 weight percent authigenic smectite is added annually to the sediment column. Minor amounts of authigenic plagioclase, phillipsite, clinoptilolite, analcime, sepiolite, siderite and apatite are also being formed within the sediments. The relationship between reduced pore water Fe and smectite formation suggests that reverse weathering reactions resulting in either authigenic nontronite or mixed-layer smectite-illite may occur in all anoxic marine sediments rich in terrigeneously-derived, poorly-crystalline "kaolinite" and containing enriched pore water Si02. Assuming that 10 percent of the total flux of the world river sediments delivered to the ocean is deposited in Kaneohe Bay-type environments and that rates of reaction are similar to those observed in Kaneohe Bay, then approximately 6 percent of the CO2 consumed by rock weathering may be returned annually to the atmosphere by these reactions. / Bibliography: leaves 258-281.