471 research outputs found

    港珠澳大桥与珠江口城市群的协调发展

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    交通基础设施建设对地区经济和城市群协调发展具有深远的影响。港珠澳大桥是珠江口南部的重要通道,其建成后能提升珠江口西岸地区城市的区位优势,促进城市融合和经济发展,推动珠江口城市群的协调发展;能满足日益增长的区域交通需求,改变珠三角地区的交通空间格局。本文从城市群协调发展的判断标准出发,对港珠澳大桥影响珠江口城市群协调发展的效应进行了分析

    Numerical research on hypoxia in the Pearl River Estuary in summer

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    本文根据珠江口海域的生态动力学特征,建立了适用于珠江口的三维生态动力学模式,对珠江口的溶解氧进行数值研究。首先建立合理的水动力模式,在此基础上,建立FENNEL生态模式。FENNEL生态模式是以氮循环为核心的NPZD模式,包含浮游动物、浮游植物、叶绿素、硝酸盐、氨盐、溶解氧、大碎屑氮、小碎屑氮、大碎屑碳、小碎屑碳、无机碳、总碱度12个生态变量组成。根据珠江口自身的特点,加入了磷酸盐、大碎屑磷和小碎屑磷三个生态变量,并考虑了磷酸盐对浮游植物生长的限制作用、悬浮泥沙造成的光衰减效应、底泥耗氧过程及浮游植物的呼吸过程,可以较真实的反应珠江口的生态情况。最后利用建立的生态动力模式,分析找出影响珠江口底...According to the ecosystem character of the Pearl River Estuary (PRE), a three dimensional ecosystem model was set up for the dissolved oxygen (DO) research.First of all, a verified hydrodynamic model was set up. Then on the basis of the appropriate hydrodynamic model, the Fennel ecosystem model was united to run,which is a nitrogen-based model, shorted as NPZD model, including twelve variables,e....学位:理学硕士院系专业:海洋与环境学院环境科学与工程系_环境管理学号:2262008115158

    Rates and Influence Factors of Water Nitrification and Inorganic Nitrogen Uptake in Pearl River Estuary

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    氮是海洋初级生产力的主要限制因素之一,海洋氮循环过程与碳、磷等其它生源要素的循环紧密联系,影响有机物输出,调控海洋生物泵效率和大气二氧化碳水平,在海洋生物地球化学循环过程中扮演极其重要的角色。硝化作用和浮游植物吸收是氮循环中的重要过程,大量人为来源活性氮的排放对河口和近海的生物地球化学过程产生了显著影响,并影响了氮营养盐内部转化过程。本研究于2015年7月间,对珠江口的11个站位进行了调查,覆盖了珠江口淡水区域、咸淡水混合区和冲淡水区。 本研究首次应用氮稳定同位素示踪技术,调查了夏季珠江口水体的硝化速率和分布。本研究测得珠江口上游淡水区域的硝化速率为4.00-17.64μmol/L/d,中游...Nitrogen is one of the limiting factors of ocean primary productivity. Coupled with other biogenic elements, such as carbon and phosphorus, nitrogen cycle plays an important role on marine biogeochemical process by controlling export of organic matter, efficiency of biological pump and atmospheric CO2 level. Input of growing anthropogenic nitrogen via river significantly changes the composition of...学位:理学硕士院系专业:海洋与地球学院_海洋化学学号:2232013115139

    Observation and Dynamical Analysis of Hydrographic Characteristics in the Pearl River Estuary in summer of 2015

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    本文以实测CTD数据为基础,总结了2015年夏季珠江口海域及其冲淡水扩展路径上的水文特征。在结合遥感风场和定点浮标风场数据的基础上,分析了台风“莲花”影响下珠江口水体的温、盐度特征,以及珠江冲淡水扩展方式对于风场变化的响应情况。同时对航次过程中观测到的温度逆转现象的特征进行统计分析;并结合遥感数据对冲淡水影响区域的海表温度数据和叶绿素a浓度的分布特征进行研究。 2015年7月6日至17日珠江口航次CTD资料的分析表明:在香港的西南侧观测到相对的低温高盐中心;珠江口附近海域存在海水的垂向逆温现象,逆温差平均值为0.42℃,上界深度在1m-6m间,下界深度在3m-10m间,逆温层平均厚度约为4m...On the basis of the in-situ CTD data, the hydrological characteristics and the expanding patterns of the Pearl River Diluted Water (PDW) have been studied. The paper has also analyzed the influencing factors with the help of the remote sensing and in-situ wind data. Then the sea surface temperature and Chl-a distributions have been applied to reveal the PDW. Meanwhile, the temperature inversion al...学位:理学硕士院系专业:海洋与地球学院_物理海洋学学号:2232014115128

    Sedimentary Nitrogen Removal in the Pearl River Estuary in Autumn

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    珠江口作为珠江流域的入海口,位于华南广东省的最南端,其南面通向南海北部,周围紧邻着经济高度发达、人口稠密的珠江三角洲经济区。珠江口的氮循环受到周边区域的工业、农业、水产养殖和生活污水排放的影响日益严重,富营养化等一系列相关的生态负面效应随之而来。珠江口内部氮元素的迁移转化情况亟待研究了解。 本研究主要专注于珠江口内的水环境中沉积物内各种氮移除过程及其脱氮速率。 本研究采用了目前在脱氮研究领域最先进的同位素配对技术计算模式,此方法用氧化亚氮的氮同位素比值修正了厌氧铵氧化对反硝化速率计算造成的干扰,并且将各反应的氧化亚氮产率以及厌氧铵氧化的氮气产率都考虑进计算中;此种同位素配对计算模式可以在同...The Pearl River Estuary is the entrance of the Pearl River drainage basin to the sea, which is situated at the south end of Guangdong Province in South China and faced with the northern part of the South China Sea. A number of developed cities of the Pearl River Delta encircle the Pearl River Estuary. The nitrogen cycle system in the Pearl River Estuary has been severely perturbed by the stress of...学位:理学硕士院系专业:海洋与地球学院_海洋化学学号:2232012115129

    Study of microbial community structure involved in methane and nitrogen cycles and relationship between microbes and environment along sediment core from Qi'ao Island of Pearl River Estuary

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    淇澳岛位于珠江口伶仃洋,是珠江出海口的第一道大门,珠江口淇澳岛附近水域位于陆海交汇处,沉积物富含有机质,为微生物提供了充足的碳氮源。本文对采集自珠江口淇澳岛海岸带沉积物样品进行了分子生态学调查及微生物培养,研究了样品中参与碳循环,氮循环及硫循环过程中微生物的多样性及群落结构并对它们与环境的关系进行了分析。 对采集自珠江口淇澳岛海岸带沉积物样品,通过构建环境样品的甲烷产生及甲烷氧化相关微生物16SrRNA克隆文库,16SrRNA序列测定、系统发育分析以及采用T-RFLP分析的方法,调查了珠江口淇澳岛海岸带沉积物参与甲烷循环的微生物群落结构及垂直分布情况。沉积物样品中甲烷产生及甲烷氧化相关微生物...Qi'ao Island, located in the Lingdingyang of Pearl River, is the first outlet of Pearl River freshwater flow to the South China Sea.The water surrounding Qi'ao Island connects the river and open sea.The sediment here is rich in organic matters,which provide abundant carbon and nitrogen sources for microbes. The sediment cores were investigated by molecular ecology approaches and methanogen were en...学位:理学硕士院系专业:生命科学学院生物学系_生物化学与分子生物学学号:2172006115226

    Spatial-temporal Distribution and Ecological Risk Assessment of Quaternary Ammonium Compounds in Urban Estuarine Sediments

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    四季铵盐化合物(QACs)是一类主要的阳离子表面活性剂,广泛使用于衣物柔顺剂、消毒剂、个人护理品等产品中。QACs易吸附于沉积物上且不易降解,欧美国家于上世纪八十年代已经禁止部分难降解QACs的使用,而亚洲国家仍在大量使用QACs作为商业产品的主要有效成分。在城市化河口环境中关于QACs的分布特征和环境行为的研究还很少。本研究进一步优化了QACs在沉积物的痕量分析方法,选取珠江口这一典型城市化河口区域,研究其表层沉积物中QACs的分布特征和环境行为,并对比分析珠江口沉积物中其他污染物(207种)的浓度和储量;通过解析珠江口和东京湾沉积柱中QACs的沉积记录,反演其在不同区域的污染输入历史;最后...Quaternary ammonium compounds (QACs) are one of the major classes of cationic surfactants used as the ingredients in fabric softeners, disinfectants, personal care products and so on. QACs tend to adsorb strongly on sludge and sediment due to their physicochemical properties, therefore QACs tend to be persistent in the nature environment. European countries carried out a voluntary phase-out of Dia...学位:理学硕士院系专业:环境与生态学院_环境科学学号:3332013115173

    Sources and Transformation of Dissolved Organic Matter as Indicated by Amino Acids in the Pearl River Estuary, China and Northern South China Sea

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    河口溶解态有机物(DOM)的生产,降解与转换调控着由陆地传输到海洋的碳的输出与碳的最终去向,然而由于河口环境的复杂性,示踪DOM的来源与生物活性是比较具有挑战性的。氨基酸作为生物标志化合物可以通过含量,对有机碳的相对贡献量,组分的统计学特征变化,手性同系物比值等不同手段,对海水中有机物经历的生物地球化学过程进行研究。本文,通过采集珠江口上游,中游和下游区域以及南海北部陆架区域的海水样品,结合各个区域的物理以及其他生物化学参数定义不同区域主导的生物地球化学过程;通过颗粒态氨基酸(PHAA),总溶解态氨基酸(TDAA)以及它们的手性同系物,从DOM的分子层面上,研究珠江口不同区域以及南海北部陆架区...In the estuary, production and transformation of dissolved organic matter (DOM) regulate the carbon export and transformation from land to ocean. It’s challenging to trace the sources and transformation of DOM because of the complex environments in the estuary. The application of amino acids in marine research mainly includes abundance and composition of amino acids, AA carbon yield (%), principal...学位:理学硕士院系专业:海洋与地球学院_海洋化学学号:2232014115130

    Researching on nitrite-oxidizing bacteria communities from the Pearl River estuary to the South China Sea basin

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    氮元素的生物地球化学循环几乎完全依赖于海洋生态系统中丰富的微生物调节。硝化作用(包括氨氧化过程和亚硝酸盐氧化过程)就是一个由微生物所介导的氧化反应,分别由氨氧化细菌、古菌(ammonia-oxidizingbacteria,AOB;ammonia-oxidizingarchaea,AOA)和亚硝酸盐氧化细菌(nitrite-oxidizingbacteria,NOB)介导。长期以来氨氧化作用一直被视为硝化作用的限速步骤,因此,亚硝酸盐氧化过程一直被人们所忽略。直到最近,在对纳米比亚氧最小层、北太平洋热带东部地区上层水体与氧最小层研究时均发现亚硝酸盐氧化率可能比氨氧化率高,且2步氧化反应并没有必...The biogeochemical nitrogen cycle is almost totally dependent on regulation by abundant microorganisms in marine systems. Nitrification (ammonia oxidation and nitrite oxidation) is carried out by specific groups of prokaryotes: ammonia is firstly oxidized to nitrite by ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA), and subsequently to nitrate by nitrite-oxidizing bacteria (N...学位:理学硕士院系专业:海洋与地球学院_海洋生物学学号:2232012115132

    Non-conservative behaviors and biogeochemistry of molybdenum in coastal waters

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    本论文调查了Mo在珠江口和台湾海峡西部的时空分布并探讨了其行为机制。由于生活污水和工业废水的排入,珠江口虎门上游水体相对还原,而珠江口下游以及台湾海峡西部水域,受沿岸流以及海水侵蚀的影响,水体主要为氧化环境。研究发现,受近岸水体的海流、藻的活动以及近岸物质输送的影响,Mo在这些水体中的行为不同。对三角褐指藻的室内培养实验证明,藻的生长及其生理活动对环境中的微妙变化非常敏感,如Cu、Mo以及CO2浓度。我们主要的结果及结论如下: 1.在珠江口中,Mo的分布为:溶解态,淡水端至海水端逐渐升高(8月,6.2→96.2nmol/L;12月,19.2→103.0nmol/L),分布受淡水和海水的混合过...We investigated seasonally and spatially biogeochemical behaviors of molybdenum (Mo) in the Pearl River estuary and western Taiwan Strait. The upper Pearl River estuary was characterized with low redox potentials as directly receiving seawage and industrial effluents nearby, while the lower Pearl River estuary and western Taiwan Strait are generally oxic as influenced from coastal currents and sea...学位:理学硕士院系专业:环境与生态学院_环境科学学号:2262011115144
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