摘要
海洋锋面存在于特征明显不同的2种或多种水系或水团交界处,锋面区域形成的次生环流和辐聚作用可显著影响到海洋中的物质输运与生物生产,故受到海洋学家的广泛关注。研究发现,我国近海陆架存在14个永久性的准静止锋面(渤海海峡锋面、山东半岛沿岸锋面、苏北沿岸锋面、西韩湾锋面、京畿湾锋面、济州岛西锋面、长江环形浅滩锋面、闽浙沿岸锋面、黑潮锋面、台湾沿岸锋面、闽粤沿岸锋面、珠江口沿岸锋面、琼东锋面和北部湾锋面),且部分海域观测到双锋面、穿刺锋面和锋面波等现象。它们与陆架环流及其他动力过程(如:涡旋、内波等)共同控制着我国边缘海的物质能量输运与交换以及生物生产力格局。近岸物质沿锋面、跨锋面输运与锋区的垂向输送过程对我国边缘海生物地球化学循环和生态过程存在显著季节性影响。冬季到春季,沿岸锋面松弛能够加强物质从近岸向陆架的输运,进而在空间上调制春季藻华暴发的时间与量级;夏季到秋季,我国边缘海存在显著的潮汐锋面系统,锋面的辐聚效应以及次级环流可显著提高锋面区域的营养盐浓度和改善光照水平,对浮游植物的生长聚集起到促进作用,故在富营养化的河口与沿岸海域,锋面区域容易成为赤潮或缺氧高发区。此外,锋面的物理屏障作用使得两侧水团保持相对独立的物理与化学特征,因而在我国边缘海生境区划和生物多样性梯度变化等方面扮演重要角色,这些研究对认识我国边缘海物质循环与生物生产的控制机制具有重要作用。未来仍需充分结合观测与卫星资料,运用多过程耦合的高分辨率模型,深入认识锋面的精细结构与动态变化,加强亚中尺度和小尺度过程及其生态效应的研究。
Ocean fronts exist at the boundaries of two or more water masses with distinct characteristics.The secondary circulation and convergence on the front can significantly affect marine matter transport and biological production.In the marginal seas of China(MSC),there are fourteen typical fronts(including Bohai Strait Front,Shandong Peninsula Coastal Front,Jiangsu Coastal Front,Seohan Bay Front,Kyunggi Bay Front,Western Chejudo Front,Yangtze Bank Ring Front,Min-Zhe Coastal Front,Kuroshio Front,Taiwan Bank Front,Min-Yue Coastal Front,Estuarine Front of Pear River,Coastal Front of Eastern Hainan Island,and Coastal Front of Beibu Gulf).Meanwhile,sub-mesoscale and small-scale processes such as double fronts,penetrating fronts,and frontal waves were observed in these frontal zones.Together with shelf circulation and other meso-and sub-mesoscale processes(such as eddies,internal waves,etc.),fronts control the transport and exchange of matters and energy in the MSC.Previous studies have found that the transport of matters along and across the front played a crucial role in the seasonal biogeochemical cycle and biological process in the MSC.From winter to spring,the frontal relax can enhance the transport of nutrients from the nearshore to the shelf,and modulate the timing and magnitude of the spring phytoplankton blooms.From summer to autumn,the convergence effect and the secondary circulation from fronts(e.g.,estuarine fronts and the fronts formed around the Yellow Sea Cold Water Mass)can significantly increase the nutrient and light levels and play an important role in promoting the growth and aggregation of phytoplankton.In the eutrophic estuaries and coastal waters,the frontal zone can be a hot-pot of red tide or hypoxia.In addition,the physical barrier effect of the front maintains relatively independent physical and biogeochemical characteristics for the water masses of both sides,and front thus plays an important role in the biogeographical zonation,and the biodiversity gradients in the MSC.Based on our understanding to frontal effects on the biogeochemical cycling and biological production in the MSC,it is necessary to carry out the ocean observations for the fine structure and variability of the fronts,the frontal sub-mesoscale and small-scale processes,combined with high-resolution satellite data and numerical models.The ecological effects from sub-mesoscale and small-scale processes deserved a deep exploration via an interdisciplinary method.
作者
刘东艳
吕婷
林磊
韦钦胜
LIU Dong-yan;LÜTing;LIN Lei;WEI Qin-sheng(State Key Laboratory of Estuarine and Coastal Research,East China Normal University,Shanghai 200241,China;Institute of Eco-Chongming,East China Normal University,Shanghai 200241,China;College of Ocean Science and Engineering,Shandong University of Science and Technology,Qingdao 266590,China;Key Laboratory of Marine Eco-Environmental Science and Technology,First Institute of Oceanography,MNR,Qingdao 266061,China)
出处
《海洋科学进展》
CAS
CSCD
北大核心
2022年第4期725-741,共17页
Advances in Marine Science
基金
国家自然科学基金重点项目——我国陆架海硅藻稳态转换特征及环境驱动机制研究(42030402)
国家自然科学基金面上项目——厚壁硅藻具槽帕拉藻在黄海增殖成因及对生物硅循环的影响(41876127)
中央级公益性科研院所基本科研业务费专项资金资助项目——人类活动和自然变化影响下的长江口缺/脱氧过程(GY0220S3)。
