秦皇岛海域海流特征及规模化养殖对其影响的观测研究

Current characteristics and its response to large-scale mariculture in Qinhuangdao coastal area based on in-situ observation

秦皇岛海域是辽东湾与渤海中部及渤海湾进行物质和能量交换的重要通道。本文基于海床基观测平台获取的夏秋季海流连续观测资料,运用调和分析和滤波等方法对该海域的海流特征及其对规模化养殖的响应进行了研究。结果表明:秦皇岛海域最显著的潮流是M_2分潮流,其最大流速介于20.0～36.9 cm/s之间,远小于辽东湾东部海域M_2分潮流最大流速;秋季秦皇岛海域余流流速介于0.2～2.5 cm/s之间,整体上较辽东湾东侧海域余流弱,辽东湾底层可能存在逆时针的弱环流系统;夏季秦皇岛海域M_2和K_1分潮流的最大流速均大于秋季;养殖活动对余流影响较大,养殖区中部A7、A8站余流的垂向平均流速比养殖区边缘A6站分别减小76%和18%左右。

The Qinhuangdao coastal area is a significant passage through which the substance and energy are exchanged among the Liaodong Bay,the central of Bohai Sea and the Bohai Bay.In this paper,based on the in-situ current data obtained from seabed-based platform continuously in the Qinhuangdao coastal area in summer and autumn,we study the characteristics of current and its response to large-scale mariculture by means of harmonic analysis and filtering.The results are shown as follows:the most prominent semi-diurnal tidal current is the M 2 tidal component with the maximum tidal velocity ranging from 20.0 cm/s to 36.9 cm/s,which is much smaller than the maximum velocity of M 2 tidal current in the east side of Liaodong Bay.In autumn,the velocities of the residual currents in the Qinhuangdao coastal area,which are between 0.2 cm/s and 2.5 cm/s,are weaker than those in the east side of Liaodong Bay.Meanwhile,there may exist a weak clockwise circulation in the bottom of the Liaodong Bay.In summer,the maximum velocities of M 2 and K 1 tidal current components are larger than those in autumn.Aquaculture activities have a greater impact on the residual currents.Compared with the vertically-averaged residual current in site A6 which located at the edge of the culture zone,the currents of A7 and A8 sites located in the central of the culture zone decrease by almost 76% and 18%,respectively.