海洋生物分类与系统演化实验室知识库

放射虫是单细胞海洋原生动物，主要营浮游生活，分布广泛，多样性程度极高，是海洋微体古生物学的重要研究对象。本研究基于采集自黄海和东海浅水陆架区、西北太平洋边缘海深水区以及赤道西太平洋的三批表层沉积物样品，对三区域放射虫进行调查分析，辅以从网络环境数据库提取的多年环境数据的年平均分析资料，以探究表层沉积物中放射虫组合与特定水体环境的关系。主要工作成果如下：

1.对西北太平洋边缘海黄海和东海陆架区的59个表层沉积物样品的放射虫进行分析，结果表明黑潮分支流对研究区的放射虫种类组成和分布模式有重要影响。黄海陆架区放射虫丰度极低，有15个站位未发现任何放射虫。聚类分析结果表明，东海陆架区放射虫可分为三个区域性组合，即东海北区放射虫组合、东海中区放射虫组合和东海南区放射虫组合。冗余分析结果表明，海表层温度、海表层盐度和粉砂含量百分比是解释放射虫群落结构的主要底质和水文变量（p < 0.05）。

2.对西北太平洋边缘海深水区（包括南海、东海和菲律宾海）的45个表层沉积物样品的放射虫进行研究，以探讨放射虫组合与表层水文环境的关联。根据Q型聚类分析结果，研究区放射虫可分为北赤道暖流组合、北赤道暖流分叉点组合、黑潮-南海组合和黑潮-东海组合。冬季海表层温度、冬季海表层盐度和年平均硅酸盐浓度是影响放射虫种类组成的最显著环境变量，其中冬季海表层温度与放射虫种类组成的相关性最高。冬季海表层温度和冬季海表层盐度具有显著影响，这表明北赤道暖流-黑潮体系的季节性变化对放射虫的丰度特征和分布格局有重要影响。

3.对赤道西太平洋的92个表层沉积物样品进行分析以探究西太平洋暖池的放射虫。根据Q型聚类分析结果，研究区的放射虫可划分为三个主要的放射虫组合，即北区放射虫组合、南区放射虫组合和富筛盘藻放射虫组合。在富筛盘藻放射虫组合中，存在大量放射虫遗骸和硅藻碎片共存的现象。净初级生产力、海表层温度和磷酸盐浓度是解释西赤道太平洋寡营养低生产力条件下放射虫种类组成的重要环境变量。

本工作主要创新点为：对于西北太平洋表层沉积物样品，基于严格的数理统计方法和丰富的环境数据库，首次探讨了黑潮分支流对东海和黄海浅水陆架区放射虫分布特征的影响，首次阐述了北赤道暖流-黑潮体系与西北太平洋边缘海深水区放射虫物种组成的内在联系，首次提出初级生产力是西太暖池西区放射虫物种组成的决定性因素。

Radiolarians, being important subject of marine micropaleontology, are unicellular marine planktonic protists that have wide distribution and high diversity. This study was based on the sea surface sediments collected from the northwest Pacific, including the shallow-water shelf area of the Yellow Sea and the East China Sea, the deep-water marginal seas of the northwest Pacific, and the western equatorial Pacific. Combined with the annual average data derived from online environmental database, the radiolarians in the study area were investigated to explore the relationships between radiolarian assemblages in the surface sediments and environmental conditions. The main results are as follows:

 1. The radiolarian assemblages of 59 surface sediment samples were analyzed in the shelf area of the marginal seas in the northwest Pacific, including the Yellow Sea and the East China Sea. The derivative branches of the Kuroshio Current had an important influence on the radiolarians composition and distribution pattern in the study area. The abundance of radiolarians in the Yellow Sea was quite low, and no radiolarians were detected in 15 stations of the Yellow Sea. Based on the results of cluster analysis, radiolarians in the shelf area of the East China Sea can be divided into three regional groups: the East China Sea north region group, the East China Sea middle region group, and the East China Sea south region group. The results of the redundancy analysis indicated that sea surface temperature, sea surface salinity and silt percentage were the main sedimental and hydrological variables that explained the structure of radiolarian assemblages (p < 0.05).

2. In the marginal seas of the northwest Pacific, including the South China Sea, the East China Sea, and the Philippine Sea, radiolarians of 45 surface sediment samples were examined to explore the correlations between radiolarian assemblages and the surface hydrography. According to the results of Q-mode cluster analysis, radiolarian assemblages in the study region can be divided into four major assemblages, i.e. the North Equatorial Current assemblage, the North Equatorial Current Bifurcation assemblage, the Kuroshio-South China Sea assemblage, and the Kuroshio-East China Sea assemblage. Winter sea surface temperature, winter sea surface salinity and annual silicate concentration were the most important environmental parameters determining the species composition, among which winter sea surface temperature displayed the strongest relation with the radiolarian composition. The remarkable influences of winter sea surface temperature and winter sea surface salinity indicated that the seasonal variation of the North Equatorial Current-Kuroshio Current system had a great influence on the abundance and distribution pattern of the radiolarians.

3. In the equatorial western Pacific, 92 surface sediment samples were collected to study radiolarians in the Western Pacific Warm Pool. The results of Q-mode cluster analysis showed that three main radiolarian faunas were obtained: the north fauna, the south fauna, and the Ethmodiscus-rich fauna. The co-existences of excessively abundant radiolarian skeletons and diatom fragments of Ethmodiscus were observed in the Ethmodiscus-rich fauna. Net primary production, sea surface temperature, and phosphate, were important environmental variables that explained the radiolarian composition in the western equatorial Pacific with oligotrophic warm conditions.

       Main innovation points of this work are as follows: in the surface sediments of the northwest Pacific, based on rigorous statistical methods and detailed environmental databases, the influences of the derivative branches of the Kuroshio Current on the distribution patterns of radiolarians were discussed for the first time in the shallow-water shelf area of the Yellow Sea and the East China Sea. The relationships between radiolarians composition and the North Equatorial Current-Kuroshio Current system were firstly explained in the marginal seas of the northwest Pacific. It is first presented that primary production was the crucial determinant of radiolarian composition in the western Western Pacific Warm Pool.

第1章 绪论. 1

1.1 放射虫简介. 1

1.2 放射虫生态学研究发展史. 2

1.2.1 国际发展史... 2

1.2.2 国内发展史... 4

1.3 西北太平洋放射虫研究现状. 6

1.3.1 东海和黄海陆架区放射虫的研究报道... 6

1.3.2 西北太平洋边缘海黑潮影响区域放射虫的研究报道... 7

1.3.3 西太暖池区西部放射虫的相关研究... 8

1.4 影响放射虫分布的主要环境因素. 8

1.4.1 深度... 8

1.4.2 温度... 9

1.4.3 盐度... 9

1.4.4 初级生产力... 9

1.4.5 叶绿素a. 10

1.4.6 营养盐（硝酸盐和磷酸盐）... 11

1.4.7 硅酸盐... 11

1.5 研究目的和意义. 12

第2章 环境数据库在表层沉积物放射虫研究中的应用  14

2.1 引言. 14

2.2 材料与方法. 16

2.2.1 样品处理... 16

2.2.2 Matlab主程序... 17

2.3 西北太平洋边缘海放射虫研究实例验证. 18

2.4 小结. 20

第3章 东海和黄海陆架区放射虫种类特征及对黑潮分支流的指示  21

3.1 研究区概况. 21

3.1.1 地理概况... 21

3.1.2 水文特征... 21

3.2 材料与方法. 24

3.2.1 样品采集与处理... 24

3.2.2 底质和水文环境资料... 24

3.2.3 数据统计分析与处理... 31

3.3 结果. 32

3.3.1 东海与黄海陆架区全部站位放射虫丰度特征（n=59）... 32

3.3.2 东海与黄海陆架区简化站位放射虫丰度特征（n=24, inds.≥100）... 34

3.4 讨论. 40

3.4.1 东海与黄海陆架区放射虫低丰度特征... 40

3.4.2 东海与黄海陆架区简化站位放射虫组合特征及与水文和底质环境的关系... 40

3.5 小结. 44

第4章 西北太平洋边缘海深水区的放射虫组合及与环境因子的对应关系  46

4.1 研究区概况. 46

4.1.1 地理概况... 46

4.1.2 水文特征... 47

4.2 材料和方法. 47

4.2.1 样品采集与处理... 47

4.2.2 放射虫分类标准... 49

4.2.3 环境数据... 55

4.2.4 数据统计分析与处理... 55

4.3 结果. 60

4.3.1 放射虫丰度和多样性... 60

4.3.2 群聚结构分析... 65

4.3.3 放射虫组合与环境因子... 68

4.4 讨论. 72

4.4.1 放射虫丰度与多样性... 72

4.4.2 放射虫与环境因子的关联... 73

4.5 小结. 77

第5章 西赤道太平洋的放射虫组合及与海洋初级生产力的关系  79

5.1 研究区概况. 79

5.2 材料与方法. 80

5.2.1 样品采集与处理... 80

5.2.2 环境数据库... 80

5.2.3 数据统计分析与处理... 84

5.3 结果. 85

5.3.1 放射虫丰度特征与群聚结构... 85

5.3.2 放射虫与环境变量的关系... 90

5.4 讨论. 93

5.4.1 富筛盘藻组合中的放射虫... 93

5.4.2 北区组合与南区组合中的放射虫... 94

5.5 小结. 98

第6章 结论与展望. 99

6.1 研究结论. 99

6.2 展望. 100

参考文献. 102

作者简历及攻读学位期间发表的学术论文与研究成果. 117

致  谢    118