黄、东海海面地形在1993-2001年间的变化探讨

长期以来海面地形变化是海面变化研究领域里一个具有显著意义却相对冷寂的研究方向,卫星海面测高技术的发展为此方向的研究提供了新的思路、手段和数据。本文利用TOPEX/POSEIDON卫星的SSHA数据对黄、东海1993-2001年期间的平均海面地形的空间形态特征、变化速率的空间分布特征及年内变化特征等3个方面进行分析。研究结果表明,该海区9年平均海面地形的基本特征为:东南高、西北低,由东南向西北倾斜,最大高差超过90 CM;1993-2001年期间全海区均呈现海面上升趋势,上升速率值在5~8.6 MM/A之间,海面上升的空间分异表现为南快北慢,东快西慢。海面地形的年内变化在时间上呈正弦波动,空间上中、北部区域变化速度快,年较差大;南部区域变化速度慢,年较差小;变化空间特征复杂。     

基于线粒体控制区序列的黄海日本鳀(Engraulis japonicus)的群体遗传结构*

遗传多样性和群体遗传结构是研究群体动态变化的重要内容, 也是种质资源评估与保护的基础。日本鳀(Engraulis japonicus)是我国东部近海的重要鱼种, 具有重要的生态价值和经济价值。文章利用线粒体控制区全序列分析了黄海海域4个地理群体(北黄海北部、北黄海南部、南黄海北部和南黄海中部)日本鳀的遗传多样性、种群遗传结构和历史动态变化。结果显示, 131个样品检测到了126个单倍型, 且4个群体的单倍型多样性均很高, 其中北黄海南部群体的最低(0.995±0.009), 南黄海中部群体的最高(1.000±0.014)。而核苷酸多样性均较低, 为0.010±0.005 ~ 0.011±0.006。主成分判别分析(DAPC)和遗传分化系数F_st表明4个群体无明显的群体分化现象, 群体间的遗传同质性水平高, 分子方差分析(AMOVA)也显示分子变异基本来自于群体内, 并且没有明显的群体遗传结构。贝叶斯系统发育树分析发现, 黄海日本鳀有2个谱系, 谱系1和谱系2的分化时间为0.701Ma前, 可以追溯到更新世期间; 进一步中性检验和核苷酸错配分布分析表明这2个谱系可能发生过群体扩张。贝叶斯天际线图则显示黄海鳀鱼的有效群体数量在0.150Ma前发生了明显的下降。     

Distribution of heavy metals and nutrients in rainwater in coastal regions between the southern Yellow Sea and East China Sea

Rainwater samples were collected in series in Qianliyan Island (southern Yellow Sea) and Shengsi Archipelago (East China Sea) between May 2000 and May 2002, chemical analysis for pH values,concentrations of heavy metals (Cu, Pb, Zn and Cd) and nutrients (NH4^-, NO3^-, PO43^-, SiO32^-) were performed.Results indicate that concentrations of most of the heavy metals and nutrients in rainwater show clear seasonal variation, i.e. high level in winter and low level in summer. Regionally, concentrations are higher in the southern Yellow Sea than in the East China Sea, but the annual input of heavy metals into oceans by wet deposition is similar in both stations. However, the input of nutrients by wet deposition in the East China Sea is 2-3 times higher than that in the southern Yellow Sea. In individual, Pb and PO4^3- are input to the sea mainly by dry deposition; whereas Cu, Zn, Cd and N compounds are input dominantly by wet deposition, the N/P ratios in the rainwater from two stations are much higher than those in seawater, showing a significant impact of atmospheric wet deposition on marine production and biogeochemical circulation of nutrients in these sea regions.     

南黄海6.1级地震前海安台形变电阻率异常特征

追踪研究黄黄海６．１地震前，松散覆盖层巨厚地区形变电阻率异常特征。探讨形变电阻率在破坏性争跟踪中的作用。     

基于GIS的东黄海渔场影响因子分析

利用地理信息系统(GIS)技术、结合近年对东黄海海洋渔业资源与环境的调查资料,对东黄海渔场的渔业资源变化的主要影响因子进行空间分析与叠加,得到该渔场的资源分布与水温、初级生产力、饵料、底质等因子的时空分布专题图,经过相关分析,即可掌握当前该渔场资源的概况。     

Simulation and analysis on seasonal variability of average salinityin the Yellow Sea

The CTD (conductivity, temperature and depth) data collected by six China-Korea joint cruises during 1996-1998 and the climatological data suggest that the seasonal variability of average salinity in the Yellow Sea (Sa) presents a general sinusoid pattern. To study the mechanism of the variability, annual cycles of Sa were simulated and a theoretical analysis based on the governing equations was reported.Three main factors are responsible for the variability: the Yellow Sea Warm Current (YSWC), the Changji-ang (Yangtze) River diluted water (YRDW) and the evaporation minus precipitation (E-P). From December to the next May, the variability of Sa is mainly controlled by the salt transportation of the YSWC. But in early July, the YSWC is overtaken and replaced by the YRDW which then becomes the most important controller in summer. From late September to November, the E-P gradually took the lead. The mass exchange north of the 37癗 line is not significant.     

南黄海盆地地震波传播特征分析

针对南黄海盆地浅水区域,利用拟Q谱法反演Q值来建立大致符合工区实际的吸收衰减模型。并使用射线参数泰勒展开法,计算地层累积吸收衰减量在不同偏移距、不同频率和不同深度下的变化情况。在此基础上,建立了理论速度模型,并利用二维有限差分声波方程模拟技术进行单炮地震记录正演,通过速度谱分析,以了解该工区浅水域多次波的发育情况。理论与实际数据分析显示,该工区的浅层衰减占主导作用,多次波能量较强,干扰严重。     

南黄海千里岩附近海域第四纪构造活动特征

南黄海千里岩附近海域是千里岩隆起区地震活动较强烈的区域,对该区域新近获得的单道地震剖面的分析表明,海底第四纪沉积层中发育较多的褶皱和断层构造,断层以逆断层为主,褶皱则主要为平缓斜歪褶皱,为断层活动引起.褶皱和断层构造多形成于中更新世以前,千里岩断裂等部分断层最新活动至晚更新世,且具有生长断层的特征,反映了区域较强的活动...     

南黄海表层沉积物中钙质超微化石的分布

对南黄海地区47个表层沉积物样品进行了钙质超微化石分析.结果表明,该区超微化石组合主要以Emiliania huxleyi和Gephyrocapsa oceanica占优势.钙质超微化石总丰度分布不一,主要受水深和黄海暖流的控制.E.huxleyi和G.oceanica两个优势种的平面分布规律也各不相同,E.huxle...