夏季台湾海峡水及黑潮次表层涌升水向东海近陆架区营养盐输送通量的估算

According to historical mean ocean current data through the field observations of the Taiwan Ocean Research Institute during 1991–2005 and survey data of nutrients on the continental shelf of the East China Sea(ECS) in the summer of 2006, nutrient fluxes from the Taiwan Strait and Kuroshio subsurface waters are estimated using a grid interpolation method, which both are the sources of the Taiwan Warm Current. The nutrient fluxes of the two water masses are also compared. The results show that phosphate(PO4-P), silicate(SiO3-Si) and nitrate(NO3-N) fluxes to the ECS continental shelf from the Kuroshio upwelling water are slightly higher than those from the Taiwan Strait water in the summer of 2006. In contrast, owing to its lower velocity, the nutrient flux density(i.e., nutrient fluxes divided by the area of the specific section) of the Kuroshio subsurface water is lower than that of the Taiwan Strait water. In addition, the Taiwan Warm Current deep water, which is mainly constituted by the Kuroshio subsurface water, might directly reach the areas of high-frequency harmful alga blooms in the ECS.     

Upward transport of iron at the west shelf edge–slope of the Okinawa Trough in the East China Sea

We studied the behavior of chemical substances in the upper 300 m of the water column across the continental shelf–slope interface in the East China Sea off the Okinawa Trough. The behaviors of iron, inorganic nutrients, and humic-like fluorescent dissolved organic matter were strongly influenced by the extensive water exchange between the East China Sea and the Kuroshio Current across the shelf break and slope via upwelling and frontal processes. We attributed the high humic-like fluorescent intensity at the subsurface of the shelf break and slope regions to the lateral supply of humic-like fluorescent dissolved organic matter from the shelf sediments to the outer shelf region due to the intrusion of shelf water into Kuroshio subsurface water. We found that the behavior of iron at the continental shelf–slope was remarkably different from the conservative mixing of inorganic nutrients and humic-like fluorescent dissolved organic matter. In deep and bottom waters at the shelf–slope, high total iron concentrations, which were closely related to water transmittance, possibly resulted from the swept transport of iron-rich resuspended sediments over the shelf floor from the slope by the invading Kuroshio Intermediate Water close to the bottom.     

Response to Liu's comments on “The Kuroshio intermediate water is the major source of nutrients on the East China Sea continental shelf” by Chen (1996)

Exchanges between the East China Sea (ECS) and the Kuroshio have been recalculated by taking into consideration the intra-annual variation of salinity on the shelf. Flux through the Taiwan Strait, previously unavailable data in the Yellow Sea and in the central and northern ECS, denitrification and ground water fluxes are now also considered. The Kuroshio Intermediate Water remains the major source of nutrients on the East China Sea continental shelf, with slightly more upwelling in the dry season than in the wet season.     

Distribution of zooplankton biomass in the southeastern East China Sea

ＤｉｓｔｒｉｂｕｔｉｏｎｏｆｚｏｏｐｌａｎｋｔｏｎｂｉｏｍａｓｓｉｎｔｈｅｓｏｕｔｈｅａｓｔｅｒｎＥａｓｔＣｈｉｎａＳｅａ￥ＷａｎｇＣｈｕｎｓｈｅｎｇ；ＨｅＤｅｈｕａ；ＬｉｕＨｏｎｇｂｉｎ；ＹａｎｇＧｕａｎｍｉｎｇ；ＭｉａｏＹｕｔｉａｎａｎｄＹｕＨｏ...     

东海春季初级生产力与新生产力的研究

于1994年4月8－30日运用14C,15N同位素示踪法现场观测东海的初级生产力和新生产力。结果表明,初级生产力变化在200-2770mg／（m2·d）之间,高值出现于开阔深水区和近海富营养区,低值出现于近岸浑水区和外海贫营养区;东海初级生产力的主要限制因子是营养盐可得性和光照条件,在不同海区二者的作用地位有所不同。新生产力的变动范围在15－1372mg／（m2·d）山之间;剧烈的波动主要取决于氧化态、还原态氮的供给比例。f比变化在0．05－0．70。     

A structure of the Kuroshio and its related upwelling on the East China Sea shelf slope

The ADCP on an advanced towed fish with controllable main and tail wings, called DRAKE measured a detailed sectional structure of the Kuroshio flowing to the NE along the East China Sea shelf slope west of Okinawa. At the observation period, a countercurrent directed to the SW formed in near-bottom water on the shelf slope. The horizontal flow perpendicular to the stream axis of the Kuroshio constructed a convergence zone around the boundary between the Kuroshio and the countercurrent. An intensive upwelling with the maximum velocity of 2.8 cm s^–1 was found to distribute on the shelf slope around the convergence zone. A dynamic cause of this intensive upwelling is discussed carefully.     

东海陆架环流季节变化的模拟与分析

在改进POM模式基础上,建立1个中国东部海域斜压准预报模式,利用全球海洋模式结果并结合实测资料以及高精度卫星遥感SST资料,进行了东海陆架海域温盐及环流年循环的数值模拟,并系统分析了东海陆架环流系统及其季节变化、各暖流的路径等广为关注的问题。模式结果表明：黑潮主轴主体沿陆架坡折走向,中段黑潮流幅由南至北增宽,流速变大,流核所达深度变浅。浙闽沿岸流是一典型的季风环流,台湾暖流终年表现出东、北两分支结构,其分支表现出明显的季节性变化特征。在东海东北部陆架海域,冬季黑潮以其分支形式向北入侵,夏季则主要以大陆边缘流的形式向北进入陆架。论文对各暖流的水源也进行了相应的分析。     

东海对马暖流水来源的数值模拟

本文通过二维数值模拟对1986年6月～1988年12月东海对马暖流水的来源问题进行了初步探讨,结果得出东海对马暖流水的来源基本上分为三种类型:(1)东海对马暖流水主要为东海黑潮水继续北上部分构成;(2)东海对马暖流水由东海黑潮水、东海陆架水以及东海北部黄海大陆沿岸水几部分混合而成;(3)东海对马暖流水几乎全部由东海北部的黄海大陆沿岸水构成。模拟与实测结果基本一致.     

东海黑潮主段环流子结构研究

通过对多种调查资料的综合分析,提出了东海黑潮主段子环流系统的物理模型,它是由较稳定的东海黑潮主段、经常出现(大概率)的右侧逆流和有条件出现(小概率)的外陆架逆流所构成的一个双环环流结构。部分黑潮水由主段北部进入陆架区形成外陆架逆流,或转向黑潮以东海域形成右侧逆流;由主段南部进入黑潮的陆架水,一部分来自外陆架逆流闭合了双环结构的外陆架部分;黑潮右侧逆流水大部分形成反气旋流动重新进入主流,闭合了双环结构的东部部分。     

南海东北部春季海表pCO_2分布及海-气CO_2通量

2013年南海东北部春季共享航次采用走航观测方式,现场测定了表层海水和大气的二氧化碳分压(pCO2)及相应参数。结合水文、化学等同步观测要素资料,对该海域pCO2的分布变化进行了探讨。结果表明,陆架区受珠江冲淡水、沿岸上升流及生物活动的影响,呈现CO2的强汇特征;吕宋海峡附近及吕宋岛西北附近海域受海表高温、黑潮分支"西伸"、吕宋岛西北海域上升流等因素影响,呈现强源特征。根据Wanninkhof的通量模式,春季整个南海东北部海域共向大气释放约4.25×104 t碳。     

黄、东海陆架2011年秋季活体浮游有孔虫生态分布

现代活体浮游有孔虫的生态研究是其古环境重建应用的重要基础。根据黄、东海陆架2011年秋季采集的20个垂直浮游拖网样品,分析了该海域浮游有孔虫的秋季生态分布特征。结果表明,黄海秋季基本上没有浮游有孔虫的出现。东海共发现13种活体浮游有孔虫,主要优势属种依次为Globigerinoides sacculifer、Pulleniatina obliquiloculata、Globigerina bulloides、Neogloboquadrina dutertrei和Globigerinoides ruber。浮游有孔虫丰度整体上呈现东南高,西北低的分布格局,这种分布格局反映了浮游有孔虫在黄、东海陆架区的分布主要受外海水影响强弱控制。浮游有孔虫主要属种在东海陆架呈现明显的区域分布差异:暖水种G. sacculifer是秋季陆架海区的主要优势种,其分布格局与总丰度基本一致,相对含量从南至北、从东至西逐渐降低,主要受区域表层海水温度变化的控制。G. bulloides与G. sacculifer呈相反的含量分布变化,其高含量主要出现在东海中陆架,从北往南逐渐降低,此外,在闽浙沿岸也有较高含量,表明了温度和生产力是影响G. bulloides在黄、东海陆架分布的主要因素。秋季P. obliquiloculata和N. dutertrei的高含量主要出现在东海南部中陆架区和济州岛西南黄海暖流影响区,可能受暖水与生产力的共同制约。     

长江口及邻近海区营养盐结构与限制

通过研究长江口及邻近海域溶解无机氮(DIN=NO₃-+NO₂-+NH₄+)、磷酸盐(PO₄3-)、硅酸盐(SiO₃2-)所表征的营养盐区域结构特征及影响因素,在分析营养盐绝对限制情况的基础上,划分了潜在相对营养限制区域。结果表明,123°E以西近岸表层区域DIN/P比值全年均高于16,而Si/DIN除秋季外基本小于1,显示出长江冲淡水影响下"过量氮"的特征。春夏季河口锋面区(31°~32.5°N,122.5°~124°E)硅藻的大量生长可使DIN/P异常升高和Si/DIN异常降低。秋季研究区域北部DIN/P西低东高且Si/DIN西高东低是由于在高DIN、低PO₄3-的长江冲淡水影响下,近岸受相对低DIN、高SiO₃2-的苏北沿岸流南下入侵影响而被分割而成。冬季长江口门东北部存在的高DIN/P和低Si/DIN区则主要由于寡营养盐的黑潮水深入陆架,向东北输送的部分长江冲淡水和增强的苏北沿岸流共同作用造成DIN升高所致。利用Redfield比值进行了不同站位表层潜在相对营养限制情况的区分。近岸123°E以西受高DIN、SiO₃2-长江冲淡水影响,四季多呈现PO₄3-潜在相对限制,而在春夏季由于浮游植物的大量吸收PO₄3-,造成局部PO₄3-绝对限制及潜在相对限制。春夏季氮限(DIN潜在相对限制)一般发生在外海部分站位,但较为零散。秋季除了东南外海大部分站位外,受苏北沿岸流影响在长江口北部近岸也存在氮限。随着低DIN/P的黑潮表层水(KSW)的入侵加强,冬季外海氮限站位增多。硅限(SiO₃2-潜在相对限制)在夏季发生在赤潮高发区,而冬季南部存在较多硅限站位表明KSW中SiO₃2-相对较为缺乏。     

西北太平洋黑潮源区沉积特征及黑潮输入对东海沉积物的影响

在对海流和地质背景分析的基础上将源区黑潮划分为3个区域,即北赤道流区、吕宋岛以东海区和台湾东部黑潮主干区,归纳总结了其沉积物矿物组成、元素组分特征和物源研究结论,探讨了黑潮输入对东海沉积物的影响。总体看来,黑潮源区沉积物的主要外来源是菲律宾群岛、菲律宾岛弧、台湾河流输入和亚洲大陆风尘的输入。黑潮源区沉积物矿物分布受菲律宾海沟的阻隔、北赤道流与黑潮的营力作用、海底火山热液活动和水深影响较大,常量元素组成主要与海底地形和水深有关,稀土元素组成表现出具有明显陆源输入的边缘海沉积特征,Sr、Nd同位素组成的研究在该区主要用于追踪亚洲风尘输入。由于黑潮入侵东海多分支的复杂性,东海黑潮对陆架沉积物的影响尚需深入研究。进一步研究应在台湾东部沉积物物源分析、黑潮输入对东海沉积物影响的历史变化、多指标整合的综合分析方法、有效物源识别端元的构建等方面展开。深入研究黑潮源区沉积特征及物源可有效揭示黑潮流域变化、构造活动和气候变化等,且探明黑潮输入对东海陆架沉积物分布的影响有利于揭示东海生态环境变化和海洋资源环境的可持续利用。     

Study on interaction between the coastal water, shelf water and Kuroshio water in the Huanghai Sea and East China Sea

The main processes of interaction between the coastal water, shelf water and Kuroshiowater in the Huanghai Sea (HS) and East China Sea (ECS) are analyzed based on the observation and study results in recent years. These processes include the intrusion of the Kuroshio water into the shelf area of the ECS, the entrainment of the shelf water into the Kuroshio, the seasonal process in the southern shelf area of the ECS controlled alternatively by the Taiwan Strait water and the Kuroshio water intruding into the shelf area, the interaction between the Kuroshio branch water, shelf mixed water and modified coastal water in the northeastern ECS, the water-exchange between the HS and ECS and the spread of the Changjiang diluted water.     

东海和南黄海夏季环流的斜压模式

基于拉格朗日余流及其输运过程的一种三维空间弱非线性理论，引进了黑潮边界力及长江径流，给出了东海和南黄海的夏季环流及上升流区的分布。计算结果表明：在黑潮西侧存在着台湾－对马暖流系统；进入朝鲜海峡的对马暖流来自台湾暖流、黑潮、东海混合水和西朝鲜沿岸流；黄海暖流主要来源于东海混合水，表面有部分来自对马暖流；闽浙沿岸存在上升流区且构成一带状区域；在长江口外、东海东北部和陆坡上也存在在上升流式；陆坡处上升流     

黑潮和中国近海环流

本文根据历史资料总结和讨论了黑潮对中国近海环流影响的基本结果,指出经巴士海峡进入南海和沿台湾海峡向北运动的黑潮分支,其年际变化明显,并认为该黑潮分支的运动状况对中国近海特别是南海和东海南部的中、下层环流影响显著,需要作进一步的调查研究。     

东海东北部春季若干重要水文结构的分析

本文主要基于韩国海洋研究所在东海沿岸海洋过程试验中收集的ＣＴＤ资料，分析了１９９５年春季出现在东海东北部的一些重要水文结构。结果表明，一种锋涡状结构出现在黑潮向东转折点附近。它不仅使邻近海域的水文结构变得更复杂，而且诱发黑潮水与陆架水间活跃的交换。在陆架坡折处观测到若干孤立的陆架水块，可能是锋涡的卷挟作用所致；该海域存在４个水团，即黑潮水、对马暖流水、陆架水和混合水。对马暖流水分为上下两层：上层水为变性黑潮水，盐度比黑潮水约低０．１，底层对马暖流水仅位于冲绳海槽区，并有着与黑潮中层水相同的温、盐特性；一种双锋结构出现在邻近黑潮的陆架边缘附近。在内陆架形成的陆架锋，由北向南伸展时，愈来愈偏向陆架边缘。而黑潮锋沿九州以西深槽的陆架边缘向北伸展。在黑潮转折点附近，两锋几乎合并为一条锋。狭窄的锋带由黑潮水及其变性水和陆架水的混合水所占据。     

Nutrient gradients from the eutrophic Changjiang (Yangtze River) Estuary to the oligotrophic Kuroshio waters and re-evaluation of budgets for the East China Sea Shelf

Eutrophication has become an overwhelming phenomenon in the coastal environment off the Changjiang (Yangtze River) Estuary, illustrated by an increase in nutrient concentration, frequent red-tide events and hypoxia in near-bottom waters, while the open East China Sea Shelf and Kuroshio waters remain oligotrophic. Observations made in the Changjiang Estuary and the East China Sea in 1999–2003 cover a broad range of hydrographic and chemical properties. The concentration gradients of nutrients across the shelf indicate that high levels from land-sources are constrained to the coastal and inner-shelf region by the complex circulation regime. In surface waters, nutrient species gradually decrease from eutrophic coastal to oligotrophic open shelf waters, depending on the hydrographic stages of the Changjiang, although biological uptake and regeneration in the upper water column can produce patchy character of nutrient distribution. Taiwan Current Warm Water and Kuroshio Surface Water are devoid of nutrients. Remineralization of nutrient species takes place in the near-bottom waters in the inner-shelf following extensive bacterial demand for organic matter. Hence the burial efficiency is low with regard to the biogenic species, either allochthonous or autochthonous, or both. The Kuroshio Sub-surface Waters are rich in nutrients, and their incursion into the East China Sea can be tracked by salinity and temperature, reaching within water depth of 50–100 m at mid-shelf. Relative to shelf waters, the Kuroshio intrusion is characterized by high and DIP/DOP ratios. In the water column, the ratio of DIP/DOP to is higher than the Redfield P/N value, suggesting rapid regeneration of phosphorus relative to nitrogen in the East China Sea. The results of a box-model suggest that the East China Sea Shelf do likely not export substantial amounts of dissolved biogenic elements to the open Northwest Pacific Ocean.     

基于分源物理生态耦合模型研究东海表层溶解无机氮对叶绿素季节变化的影响

东海溶解无机氮(dissolved inorganic nitrogen, DIN)有四个主要外部来源,包括黑潮、台湾海峡、河流径流和大气沉降。为探究它们的共同作用对东海浮游植物时空变化带来的多重影响,利用添加分源模块的物理-生态耦合模型分析了东海表层不同来源DIN支持的浮游植物(以叶绿素a浓度chlorophylla,chla表征)季节变化与空间分布以及它们之间的响应关系,从而评估多源营养盐对东海陆架表层浮游植物的影响。各来源DIN支持的chl a浓度中,黑潮来源和河流径流来源先后占据主导地位,且除了河流径流来源chl a,其余三种来源chl a季节变化均呈双峰结构。不同来源chl a空间分布特征存在季节变化差异,并且各来源chl a在东海陆架不同季节存在不同的主导区域,这与不同来源DIN供给的物理过程,如环流、混合、层化以及温度变化等密切相关。研究不同来源营养盐对东海浮游植物的影响对理解多重压力下东海生态系统变化有重要意义。     

An analysis on the formation mechanism of the distribution of high content of chlorophyll-a in the continental shelf edge waters of East China Sea

On the basis of the data obtained from the comprehensive Kuroshio surveys in 1987-1988,this paper analyses the oceanographic characteristics in the area (125°-130° E,27°-31° N) of the continental shelf edge of the East China Sea (E. C. S. ) and its adjacent waters and discusses the effects of the Kuroshio front,thermocline and upwelling of the Kuroshio subsurface water on the distribution of standing stock of phytoplankton (chlorophyll-a). The distribution of high content of chlorophylly-a has been detected at 20-50 in depth in the water body on the left side of the Kuroshio front in the continental shelf edge waters of the E. C. S. The high content of chlorophyll-a spreads from the shelf area to the Kuroshio area in the form of a tongue and connects with the maximum layer of subsurface chlorophyll-a of the Kuroshio and pelagic sea. The author considers that the formation of the distribution of high content chlorophyll-a in this area results from the bottom topography and oceanic environment and the