【作者】 周楠；

【导师】 赵卫红；

【作者基本信息】 中国科学院研究生院（海洋研究所） ， 海洋化学， 2012， 硕士

【摘要】 海洋溶解有机物质(DOM)是全球碳循环的重要贮库，在水体的生物和化学过程中起着重要作用，但是由于其结构和组成复杂，目前对其了解甚微。基于DOM荧光性质的三维荧光光谱的广泛应用为海洋DOM的研究展开了新的思路，多变量数据分析方法提供了新的技术手段。本文利用激发/发射矩阵光谱（EEMs）并结合平行因子分析（PARAFAC）的方法，对荧光组分进行有效分离，监测了北黄海、南海以及东海赤潮演替期间海水DOM荧光团组成和性质的差异，并结合温盐、叶绿素等物理生物参数和聚类分析的方法讨论了不同海域不同环境下海水DOM来源的主要影响因素，并对赤潮演替对DOM的影响进行了初步探讨。（1）对北黄海獐子岛附近海域12月、3月、5月三个航次的研究发现不同季节DOM的荧光组成基本一致，包含类腐殖质荧光组分C1(265/440nm)、C2(410-450/520-550nm)和类蛋白荧光组分C3(230,280/330nm)，且三者有很好的相关性，表明它们有着相同的来源或彼此间存在某种关系。各组分在不同季节不同水层的分布有在獐子岛周围海域荧光强度相对较大的共同点。通过对各组分与叶绿素a和盐度变化的关系研究发现，调查海区DOM受现场浮游植物和人类生产活动的共同作用。（2）南海1月份的样品识别出了四种荧光组分，分别为类蛋白荧光组分C1（280，230/335nm）和C4（270/310nm），类腐殖质荧光组分C2(255，320/415nm)、C3(290，350/490nm)，C4（270/480nm）。类蛋白荧光物质主要来自自陆源输入，而类腐殖质荧光物质只有在表层随着盐度的增大得到稀释，底层高盐低温区受到海洋自身有机物分解沉降的作用，出现荧光高值。聚类分析将调查区域分为四类，近岸入海口受人类活动的影响荧光物质含量大归为一类；比较靠近岸边的站位荧光值也相对较高，且水层较浅，表底层差别不大，为第二类；随着向远海的延伸，荧光强度逐渐降低，这些归为第三类；最后在远海底层的样品有类腐殖质的添加，归为第四类。（3）东海春季赤潮演替过程中DOM分解得到的六种荧光组分分别为类腐殖质荧光组分C1(265,335/470nm)、C2(245,310/400nm)、C6(300-310/510nm)，类蛋白荧光组分C3(275/315nm)、C4(235,290/330nm)、C5(305/345nm)。各荧光组分在不同水层的分布整体上呈现表层最高、中层次之、底层最低的特点，与生物活动相适应。发生赤潮演替最为明显的za断面DOM的组成和变化与其他断面有所不同，中肋骨条藻藻体的消亡降解向水体中释放了大量的类酪氨酸荧光物质，其他断面各类蛋白荧光组分之间和各类腐殖质荧光组分之间的相关性很好，主要受到陆源输入的影响，五月份的类蛋白荧光组分除陆源输入，还有沉积物间隙水的贡献。各荧光组分强度与叶绿素相关性不显著，现存浮游植物对类蛋白和类腐殖质荧光组分的直接影响都很小。通过对以上三个海域DOM的研究表明，EEMs与PARAFAC相结合对DOM荧光进行分析鉴别是一种有效可行的分析方法。不同海域DOM的组成和性质受到周围环境的影响，表现有一定的差异，赤潮演替过程中藻体的消亡降解会释放大量的类酪氨酸荧光物质，活跃的人类活动加剧了陆源有机物向海洋的输入，也在一定程度上影响了海洋DOM的分布组成。DOM光学性质的研究在监测、研究、开发利用海洋方面将具有广阔的应用前景。更多还原

【Abstract】 Marine dissolved organic matter(DOM) is an important storage of the global carbon cycle,which plays an important role in water creatures and chemical process. However, the recognitionis limited because of its complex structure and composition. The wide applications ofthree-Dimensional Fluorescence Spectrum based on fluorescence properties of DOM, providesnew ideas for Marine research and new technological methods are used with multivariate dataanalysis.In this paper, fluorescence components of DOM were identified effectively in northernYellow Sea, South China Sea and East China Sea with the course of red tide dispersion, usingExcitation/Emission Matrix spectroscopy(EEMs) combined with Parallel FactorAnalysis(PARAFAC). The differences in composition and properties of fluorophore werediscussed, and the relationships with temperature, salinity, chlorophyll and other physical andbiochemical parameters were considered. Furthermore, cluster analysis was used to assess thesimilarities and dissimilarities of the EEMs data set. The result showed the sources and othermajor influential elements of the fluorescence components in different environments.(1) According to the three times aquatic researches in December, March, May in northernYellow Sea waters around Zhangzi Island, it indicated that DOM fluorescence components weregenerally consistent in different seasons, including humic-like component C1(265/440nm),C2(410-450/520-550nm) and protein-like component C3(230,280/330nm) and three had goodcorrelation. It showed that they had the same sources or some certain relationships between eachother. Further more, all of the3components in different layers and different seasons had higherfluorescence intensity around Zhangzi Island, which was relatively large in common. Throughthe research on the relationships among fluorescence components and chlorophyll-a andvariations in salinity, it surveyed the marine DOM was influenced by both phytoplankton and human activity.(2) Four fluorescent components were identified for the samples got from South China Seain January, including two protein-like components C1(280,230/335nm), C4(270/310nm), andthree humic-like components C2(255，320/415nm),C3(290,350/490nm), C4(270/480nm).Protein-like fluorescent matters were obtained from terrestrial inputs mainly. However, thefluorescent intensity of humic-like components only decreased with increase of salinity insurface layer, and high fluorescent intensity was found in the areas with low temperature andhigh salinity. Four clusters were obtained by cluster analysis, cluster1was distributed in thecoastal location, where human activities were extensive, cluster2was mainly composed ofsamples from the area little far away from the shore, while the most samples in cluster3weredistributed in the open ocean with low fluorescent intensity, and the samples of last cluster4wereobtained form the bottom open sea with low temperature and high salinity.(3) The distributions of fluorescent components of chromophoric dissolved organic matterfrom East Sea in April and May in the succession process of red tide dispersion were disscussed.Six individual fluorescent components were identified by PARAFAC, including three humic-likecomponents C1(265,335/470nm), C2(245,310/400nm), C6(300-310nm/510nm), protein-likecomponent C3(275/310nm), C4(235,290/330nm) and C4(305/345nm). The fluorescenceintensity in surface layers was higher than that in middle layers, and it was minimum in bottomlayers, conforming to biological activities. The compositions and properties of DOM in thesection of za, where red tide dispersion happened, were different from others, and hightyrosine-like intensity was observed, which was produced by the degradation of frond. Theprotein-like and humic-like components in other sections had good relationships, showing theyhad the same sources, and terrestrial inputs influenced mainly. No significant correlation wasfound with chlorophyll, suggesting that the living algal matter contributed little to thefluorescence intensity of the seawater.The results of the discuss for DOM in different sea areas demonstrated the capability of thecombination of EEMs and PARAFAC for characterizing fluorescence of DOM. Thecompositions and characterizations in different areas were different, influenced by thesurrounding environments. The terrestrial inputs were aggravated by human activities, which influenced the characterizations of marine DOM to a large extent, meanwhile phytoplankton canalso play a impotent role in the areas where they were active. The study in optical properties ofDOM have bright prospects in survey, exploitation and application of the ocean.更多还原