【作者】 刘建波；

【导师】 王学昌；

【作者基本信息】 中国海洋大学 ， 环境规划与管理， 2010， 硕士

【摘要】 胶州湾是青岛市赖以生存和发展的重要保障,它在港口、海上运输、水产养殖业和旅游等多方面经济发展中发挥着重要的作用,但随着城市化的进程和沿岸经济的迅猛发展,胶州湾水域面积急剧缩小,其直接后果是造成海湾的纳潮量减少,气候的调节能力降低,流场改变,水动力强度减弱,水体交换和携沙能力下降,海洋自净能力降低,生态环境恶化等一系列潜在的隐患。由于胶州湾地形复杂,岸线曲折,并有大面积的滩涂存在,使用三维海洋数值模型EFDC对胶州湾进行数值模拟。对1952年和2008年的胶州湾水动力环境包括纳潮量、潮位、潮流以及水交换能力进行模拟分析,并加以比较,定量的分析随着胶州湾岸线的不同演变、海湾面积不断缩小情况下,胶州湾的水动力环境发生变化的规律。本文基于EFDC数值模型,在垂向上引入了改进的σ坐标——LCLσ坐标,开边界选取M2、S2、K1、01四个分潮预报水位作为边界驱动力,分别模拟1952年和2008年胶州湾的水动力环境,得到其流场、余流场的分布情况；引进水龄浓度概念,结合计算水交换时间的水质模型公式,在EFDC水动力的基础上计算胶州湾的水交换时间；基于纳潮量定义公式,计算了不同时期胶州湾的纳潮量。近60年来,由于岸线的自然演化及人类活动,导致了整个胶州湾的岸线、水深发生了较大的改变,胶州湾岸线从1952年的206.4.1 km减少到2008年的178.06km,水体面积从540.3 km2减少到348.07 km2,同时在浅水区等深线基本上都向湾内收缩。通过数值模式对比：胶州湾的大潮纳潮量从1952年的16.29×108m3减少为2008年的9.57×108m3,小潮时从11.07×108m3减少到6.53×108m3。整个胶州湾的湾内流速呈整体变小趋势,流速最大减少约0.90m/s,并且越靠近滩涂的位置其流速流向变化越大；由于黄岛与陆地相连以后,导致与之相关的两个强流涡不但余流速度减少,而且流涡中心均向东南方移动,同时北部海域的地形发生很大变化,直接导致此区域的余流场变弱或消失；胶州湾整体水交换时间急剧增加,从1952年的59天,增加至2008年的80天,在强混合潮的作用下,表层和底层的水交换时间相差最大不超过一天。更多还原

【Abstract】 Jiaozhou Bay is an essential condition that Qingdao exists and develops, which plays an important role in port、marine transport、aquaculture industry and travel.With the rapid development of urbanization and economy, water area of Jiaozhou Bay has shrinked tremendously in recent years, which results lots of potential hazards of the decrease of tidal prisms、reduction of the ability to regulate climate、changing of the flow field、lessening of the intensity of hydrodynamic、reducing of water exchange and the capacity of carrying sand、diminishing of the environmental capacity of the harbour、deteriorating of ecological environment and so on.According to the complex terrain, flexural coastline and the large area of beaches of Jiaozhou Bay,3-D hydrodynamic numerical model EFDC is used to simulate the area. The hydrodynamic environment of the Jiaozhou Bay in the 1952 and 2008 is simulated, which contains tidal water capacity、tide、current and water exchange. The stimulations data are compared, and the variation rule of Jiaozhou bay coastline dynamical environment changes is quantifily analysed during the changes of Jiaozhou Bay coastline and the reducing of the area in different periods.Based on hydrodynamic numerical model EFDC,the modifiedσcoordinate-LCLσcoordinate is introduced in vertical direction, and only tidal forcing-M2、S2、Ol、K1 are concerned in open boundary.The hydrodynamic environment of the Jiaozhou Bay in the 1952 and 2008 is respectively simulated, which obtain the distribution condition of tidal current fields and residual current fields.Water concentration is introduced and it is combined the water quality formula to compute the water exchange.Tthe water age of Jiaozhou Bay is calculated based on the hydrodynamic of EFDC.According to the formula of tidal prisms, the tidal prisms of Jiaozhou Bay are computed in different period.The coastline、water depth and sea area of the entire Jiaozhou Bay has been changed obviously in the recent 60 years due to Human Activities and the coastline of natural evolution. The coastline of Jiaozhou Bay has reduced from 206.41 km in 1952 to 178.06km in 2008;the sea area is 540.3 km2 in 1952 while 348.07 km2 in 2008;and at the same time, the isobath of the shoal water is basically shrinked toward interbay. During the spring tides, the tidal prisms of Jiaozhou Bay has reduced from 16.29×108m3 in 1952 to9.57×108m3in 2008;while during the neap tides,the tidal prisms in 1952 was 11.07×108m3, cutted down by 40 percent. The velocity of Jiaozhou Bay shows the trend of decrease. The maximum velocity ruduces by 90cm/s; and the velocity and direction of the tide change the more largely the more nearer the tideland. After the Huang island was connectted with land, the residual current velocity of the two strong gyres related to the Huang island not only becomes smaller, but also the center of gyres move to southeast. The topography of the northern sea of Jiaozhou Bay has gotted great change, which results the residual current fields of the area gets weaker or disappear directly. The time of water exchange of Jiaozhou Bay has increased dramatically from 59 days in 1952 to 80 days in 2008.Comparing the time of water exchange of the surface and bottom, it is not more than one day due to strong mixedtide.更多还原