【作者】 王迪迪；

【导师】 孙耀； 石晓勇；

【作者基本信息】 中国海洋大学 ， 分析化学， 2008， 硕士

【摘要】 本论文通过分析东、黄海典型海域古生产力指标(BSi、TOC)的平面和垂直分布特征,并将其含量与相应的表层沉积物中各站位和柱状沉积物中各年代的浮游植物现存量做线性回归,从而得到沉积物中BSi、TOC含量与浮游植物现存量之间的定量关系。然后以BSi、TOC为指标来重建东、黄海近200年的古生产力。通过以上研究,得到的结论如下:一、由210Pb测得南黄海10594、10694和12694站位的沉积速率分别为0.350cm/a、0.143cm/a、0.153cm/a,三站位的沉积历史大约分别为150a、200a、230a。长江口H1-18站位沉积速率为0.225cm/a,该站位柱状样约有130年的沉积历史。二、从平面分布看,BSi和TOC呈现由北向南、由近岸向远海逐渐减小的趋势,这种分布趋势与浮游植物现存量的分布趋势相似。从垂直分布看,南黄海BSi垂直含量波动较小,含量稳定;长江口及邻近海域除在1966年出现最大值外,整体来说垂直含量稳定。这与南黄海水动力条件稳定和长江口复杂的沉积环境有关。TOC的百分含量随深度增加均呈现减小的趋势,南黄海表现尤为明显,这与有机质的矿化分解作用有关。此次调查南黄海测得4.60﹤TOC/TN﹤12.61,说明沉积物中的有机质属于混源有机质;长江口测得TOC/TN﹥20,说明沉积物中有机质主要来自陆源。三、南黄海表层样中BSi、TOC与硅藻、Chla的相关性均较好,与浮游植物生物量均无好的相关性。长江口和闽浙沿岸BSi与浮游植物现存量的相关性均较好,而TOC与其相关性均不好。南黄海柱样中BSi与浮游植物现存量均具有较好的相关性,TOC与其相关性均不好。BSi峰值与历史上浮游植物现存量峰值相符,TOC含量高值一般出现在表层,而历史上浮游植物生物量、硅藻生物量较大值一般出现在20世纪60年代左右和80年代中期,Chla高值一般出现在80年代中期,所以TOC含量与浮游植物生物量、硅藻、Chla相关性不好。除BSi与Chla的相关性不好外,长江口BSi、TOC与浮游植物现存量的相关性均较好。四、以BSi为指标来推算东、黄海典型海域浮游植物现存量,得出:南黄海浮游植物现存量一般在20世纪10～20年代、30年代、60年代左右、80年代初期和19世纪80年代中期出现较大值,20世纪50年代、70年代左右出现最小值。长江口一般在60、80年代左右、40年代末和19世纪80年代末出现较大值,较小值出现在20世纪左右,其它年代含量较稳定。这与以TOC为指标来推算东、黄海典型海域浮游植物现存量得出的结论大致相符。因此,BSi和TOC均可作为古生产力指标来反演长江口及邻近海区的古生产力。以BSi和TOC为指标分别推算的南黄海浮游植物现存量存在明显的差异,这可能与TOC在沉积物中的保存效率较低有关。所以以BSi为指标来重建古海洋生产力要优于TOC。五、各形态氮磷与TOC、BSi和浮游植物现存量的相关性比各形态氮好,因此东、黄海各形态磷对初级生产力的影响较大。黄海中部TOC、BSi和浮游植物现存量与各形态氮、磷的相关性比长江口好,这可能与黄海中部水动力条件相对平静、沉积物粒度小,而长江口水动力条件复杂,沉积物粒度较大,各形态氮、磷不易在此沉积有关。温度、陆源输入、鳀鱼资源量与浮游植物现存量和古生产力指标之间存在一定的相关性,陆源输入和鳀鱼资源量与其相关性更为明显。因此陆源输入和鳀鱼资源量对古生产力的影响较大。更多还原

【Abstract】 Horizontal and vertical distribution of paleoproductivity index (BSi、TOC) in the typical areas of the East China Sea and the Yellow Sea is analyzed, and linear regression is done to get the correlations between the contents of BSi, TOC and the phytoplankton standing crop of surface sediments in all sampling sites and sediments of different age. BSi、TOC is used to rebuild paleo-productivity of the last 200 years. According to the study, the conclusions are as follows:One: Deposit velocities of 10594, 10694, 12694 were 0.350cm/a、0.143cm/a、0.153cm/a by 210Pb, deposit histories of three stations are about 150a, 200a, 230a. Deposit velocity of H1-18 was 0.225cm/a, and deposit history is about 130a.Two: From the hotizontal distributions, we get that the contents of BSi、TOC show the diminishing tendency from north to south and from coast to distant sea. The standing crop of phytoplankton shows the same tendency.From the vertical distribution, we get that the vertical contents of BSi was steady in the South Yellow sea. Except the biggest value in 1966, the vertical contents was steady in the Yangtzi River estuary. It is obvious in the South Yellow sea The percentage of TOC shows the diminishing tendency with the increase of age, this tendency was related to mineralization and degradation of organic matter. This investigation shows that TOC/TN was between 4.60 and 12.61 in the South Yellow sea, so organic matter of the sediments belonged to organic matter of mixed source, TOC/TN exceeded 20 in the Yangtzi River estuary, so organic matter of this sea is(was) from land source.Three: The correlations between BSi, TOC and diatom, Chla are all good in the surface sediments of the South Yellow sea, the correlation between BSi and diatom is best, BSi、TOC and the biomass of phytoplankton have bad correlations. The correlations between BSi and the standing crop of phytoplankton are all good, TOC is exactly on the contrary in the Yangtzi River estuary and the Coast of Fujian and Zhejiang.The correlations between BSi and the standing crop of phytoplankton were all good in the pillar samples of the South Yellow sea, TOC is exactly on the contrary. The peak value of BSi and the standing crop of phytoplankton was coherent in history, the high value of TOC was usually in the surface, the high value of the biomass of phytoplankton and diatom were usually in the 60era and the intermediate stage of 80 era of 20th century. The high value of Chla was about the intermediate stage of 80 era, so the correlations between TOC and the standing crop of phytoplankton are bad. Except that BSi and Chla has bad correlation, BSi、TOC and the standing crop of phytoplankton have good correlations in the Yangtzi River estuary.Four: The standing crop of phytoplankton is calculated by BSi in the typical areas of the East China Sea and the Yellow Sea. The conclution is that the high value of the standing crop of phytoplankton were usually in the 10-20era, 30era, about 60era, initial period of 80era and the intermediate stage of 80era of the 19th century in the South Yellow sea. The small value were usually in the 50 era and 70 era of the 20th century. The high value of the standing crop of phytoplankton are usually in the age of 60 and 80, the end of 40 and the end of 80 of the 19th century in the Yangtzi River estuary, the small value is in the 20th century, the contents in other years were steady. This conclusion matches with the conclusion of the standing crop of phytoplankton calculated by TOC. So BSi and TOC are all used as good indexes to rebuild the paleoproductivity of the Yangtzi River estuary.The standing crop of phytoplankton is calculated by BSi and TOC have evident differences. This may be related to the low stocking efficiency of TOC in the sediments. So BSi is a better index on rebuilding paleo-productivity than TOC.Five: The correlations of different phosphorus species and BSi, TOC are better than the correlations of different nitrogen species and BSi, TOC, So different phosphorus species influenced primary productivity more greatly. The correlations of TOC, BSi and different phosphorus and nitrogen species of the South Yellow sea are better than the Yangtzi River estuary, this may be related to the peaceful hydrodynamic conditions and small particle size of the South Yellow sea, and the complicated hydrodynamic conditions and big particle size of the Yangtzi River estuary.Temperature, source entry, anchovy scales deposition and indexes of paleo-productivity, the standing crop of phytoplankton had invariably correlations. source entry and anchovy scales deposition are evident. So source entry and anchovy scales deposition influence paleo-productivity greatly.更多还原