Two drifting paths of Sargassum bloom in the Yellow Sea and East China Sea during 2019-2020

The macroalgal blooms of floating brown algae Sargassum horneri are increasing in the Yellow Sea and East China Sea during the past few years. However, the annual pattern of Sargassum bloom is not well characterized. To study the developing pattern and explore the impacts from hydro-meteorologic environment, high resolution satellite imageries were used to monitor the distribution, coverage and drifting of the pelagic Sargassum rafts in the Yellow Sea and East China Sea from September 2019 to Au...     

Distribution of phytoplankton in the East China Sea and the southern Yellow Sea in spring in relation to environmental variables and dimethylsulfide compounds

The coastal ecosystems are highly sensitive to climate change and are usually influenced by variations in phytoplankton communities and water physiochemical factors. In the present study, the phytoplankton community, chlorophyll a（Chl a） and their relationships with environmental variables and dimethylsulfide（DMS） and dimethylsulfoniopropionate（DMSP） were investigated in spring 2017（March 24 to April 16） in the East China Sea（26.0°–33.0°N, 120.0°–128.0°E） and southern Yellow Sea（31.0°–36.0°N, 12...     

Analysis on the indicator species and ecological groups of pelagic ostracods in the East China Sea

Ecological adaptation and ecological groups of pelagic ostracods were examined in the East China Sea （23°30′-33°00′N, 118°30′ -128°00′E）, in relation to temperature and salinity. The data were collected in four surveys conducted from 1997 to 2000. The density, yield density, or negative exponent models were used to determine the optimal temperature and salinity of water for the thriving growth of pelagic ostracods. Thereafter, ecological groups and potential distribution patterns of pelagic ostracods were determined based on the predicted parameters such as optimal temperature and salinity, consulting the geographic distribution. The analytical results indicate that, among the numerical dominant pelagic ostracods in the East China Sea （ECS）, Euconchoecia aculeata, E. elongata, E. chierchiae, E. maimai, and Cypridina dentata, etc. are offshore subtropical water species. These species are widely distributed in the area, and they can be brought by the warm current to north offshore during spring and winter. The predicated optimal temperature （OT） and optimal salinity （OS） for Paraconchoecia decipiens, P. echinata, P. spini- fera, P. oblonga, Conchoecia magna and Porroeciaporrecta are all greater than 25℃ and 34 separately. These species are mainly distributed in the waters of the Kuroshio, the Taiwan Warm Current, and the Taiwan Strait, and therefore are designated as ocean- ic tropical water species. On the other hand, Pseudoconchoecia concerttrica is considered as offshore subtropical water species based on its geographical distribution although its OT is 19℃. The other species, though their OSs are approximately 34 and with OTs ranging from 20° to 25℃, are considered as offshore subtropical water species because they were found to be widely distributed from the South China Sea to the East China Sea.     

Study on abundance variation of pteropods in the East China Sea

1 Introduction Pteropoda, an order of marine pelagic mollusks, belongstoClassGastropoda,SubclassOpisthobranchia. The speciesofthisorder can be found all over the world buttheyareusuallyabundantinthecontinentalshelfand continental slope area. As fish diets…     

黑潮与邻近东海生源要素的交换及其生态环境效应

黑潮与东海生源要素的交换对东海的生态环境有重大影响,交换主要是经台湾东北部海域输送至东海陆架和通过日本九州西南海域由东海陆架向外海的黑潮输出两个通道。中国科学院海洋先导专项对黑潮与邻近东海生源要素的交换特征进行了系统的调查和研究,获得了一些新的认识:(1)在台湾东北部区域,碳主要以表层水-次表层水为载体输入,秋季的输入量高于夏季;黑潮溶解态营养盐的输入占据绝对主导地位,且以黑潮次表层热带水-中层水的输入为主,输入通量春季高于夏、秋季,可为东海春季水华提供一定的物质基础,但输入到东海的黑潮水其氮磷比与Redfield比值(16:1)接近,这些"正常水"——黑潮的输入显然对调和东海异常高的氮磷比有重要的作用,从而对东海的生态环境起到"稳定和缓冲"作用。所以,黑潮水对东海的输入不仅维持补充了东海生态系统运转所需的生源要素,更为重要的是缓冲了受人为影响强烈的东海海水的高氮磷比,使东海本已失常的营养盐结构向合适的氮磷比方向转变。因此,黑潮与东海生源要素的输入在一定程度上起着稳定和缓和东海生态环境的作用。(2)通过构建的海水Ba-盐度新指标体系,定量细致刻画了黑潮对东海生源物质在台湾东北部区域的输入范围和程度,黑潮次表层水从台湾东北陆架坡折处沿底部向北偏西方向入侵东海,其近岸分支可以入侵到浙江近岸,其黑潮次表层水占比仍可达到65%左右。垂直方向上,陆架外侧站位受黑潮次表层水的影响范围更大,黑潮水占50%比例位置可延伸至外侧TW0-1站位(122.59°E,25.49°N)表层,而内侧靠近大陆的站位则只限于陆架中部位置底层。     

Species composition and diversity of Euphausiacea in the East China Sea

[1]Cai Bingji. 1978. The taxonomy study on     

On sedimentation of phosphorus in specified area outside of the Changjiang Estuary

ＩＮＴＲＯＤＵＣＴＩＯＮＥｎｖｉｒｏｎｍｅｎｔａｌｐｏｌｌｕｔｉｏｎｈａｓｂｅｃｏｍｅａｖｅｒｙｓｅｒｉｏｕｓｐｒｏｂｌｅｍｗｉｔｈｔｈｅｒａｐｉｄｉｎｄｕｓｔｒｉａｌｉｚａ ｔｉｏｎ .Ｔｈｅｐｏｌｌｕｔｉｏｎｃａｕｓｅｄｂｙｐｏｌｌｕｔａｎｔｓｓｕｃｈａｓｎｕｔｒｉｅｎｔｓ ,ｈｅａｖｙｍｅｔａｌｓａｎｄｏｒｇａｎｉｃｃｏｍｐｏｕｎｄｓ(ｉｎｃｌｕｄｉｎｇｐｅｓｔｉｃｉｄｅｓ)ｅｔｃ .ｃｏｕｌｄｄａｍａｇｅｔｈｅｗｅｌｌ ｂａｌａｎｃｅｄｃｉｒｃｕｌａｔｉｏｎｏｆｎａｔｕｒａｌｅｃｏｓｙｓｔｅｍａｎ…     

南海北部和中部硅藻通量季节性变化及其对季风气候的响应

通过对南海北部和中部两套时间序列沉积物捕获器中的颗粒物样品进行硅藻分析,揭示了南海北部和中部硅藻通量的季节变化规律及其区域差异和各自对东亚季风气候的响应.研究表明在南海北部和中部海域,硅藻通量可以在一定程度上指示海洋初级生产力水平,其中南海北部硅藻通量明显低于中部,这可能与北部颗粒物样品采集期间发生的E1 Ni(n)o...     

Distribution characteristics of zooplankton biomass in the East China Sea

On the basis of the data of oceanographic survey in the East China Sea in four seasons during 1997-2000 (23°30'~33°00'N, 118°30'-128°E), the variation of total biomass and diet biomass of zooplankton and their spatial-temporal distribution and relationship with the fishing ground of Engraulis japonicus are approached and analyzed. The results show that the average biomass is 65.32 mg/m3 in four seasons, autumn (86.18 mg/m3) being greater than summer (69.18 mg/m3) greater than spring (55.67 mg/m3) greater than winter (50.33 mg/m3). The average value of diet zooplankton biomass is 40.9 mg/m3. The trends of horizontal distribution both in the total biomass and the diet biomass of zooplankton are similar. The high biomass region (250-500 mg/m3) is very limited, only accounting for 1% of the investigation area. Seasonal variation of the biomass is very remarkable in the west and north parts of East China Sea coastal waters ( 29°30'N,125°E). The horizontal distribution of diet zooplankton depends on the     

Distribution characteristics of zooplankton biomass in the East China Sea

On the basis of the data of oceanographic survey in the East China Sea in four seasons during 1997～2000 (23°30′～33°00′N,118°30′～ 128°E), the variation of total biomass and diet biomass of zooplankton and their spatial-temporal distribution and relationship with the fishing ground of Engraulis japonicus are approached and analyzed. The results show that the average biomass is 65.32 mg/m3 in four seasons, autumn (86.18 mg/m3) being greater than summer (69.18 mg/m3) greater than spring (55.67 mg/m3) greater than winter (50.33 mg/m3). The average value of diet zooplankton hiomass is 40.9 mg/m3.The trends of horizontal distribution both in the total biomass and the diet biomass of zooplankton are similar. The high biomass region (250～500 mg/m3) is very limited, only accounting for 1% of the investigation area. Seasonal variation of the biomass is very remarkable in the west and north parts of East China Sea coastal waters (29°30'N,125°E). The horizontal distribution of diet zooplankton depends on the abundance distribution of crustacean. The distribution of diet zooplankton is related to the fishing ground of Engraulis japonicus and the high-density area of young fish and larval. In spring, the central fishing ground of Engraulis japonicus (>100 kg/h) and the high-density area of young fish and larval (>100 individuals per net) are located at the same place of high-density (100～250 mg/m3)area of diet zooplankton in the middle-southern part of East China Sea or the edge of its waters.     

Ocean temperature responses to Typhoon Mstsa in the East China Sea

The MASNUM wave-tide-circulation coupled model, with 21 layers in the vertical and （1/8） °horizontal resolution, was employed to investigate the oceanic responses to Typhoon Mstsa which traversed the East China Sea （ECS） during the period of 4 - 6 August, 2005. Numerical experiment results are analyzed and compared with observation. The responses of the sea surface temperature （SST）, in a focused area of （27° -29°N, 121° - 124°E）, include heating and cooling stages. The heating is mainly due to warm Kuroshio water transportation and downwelling due to the water accumulation. In the cooling stage, the amplitude of the simulated cold wake （ -3℃ ）, located on the right side of this typhoon track, is compared quite well with that of the satellite observed SST data. The wave-induced mixing（Bv） plays a key role for the SST cooling. Bv still plays a leading role, which accounts for 36%, for the ocean temperature drop in the upper ocean of 0 - 40 m, while the upwelling is responsible for 84% of the cooling for the lower layer of 40 - 70 m. The mixed layer depth （MLD） increased quickly from 28 to 50 m in the typhoon period. However, the simulated MLD without the wave-induced vertical mixing, evolution from 13 to 32 m, was seriously underestimated. The surface wave is too important to be ignored for the ocean responses to a typhoon.     

微小辐环藻, 我国硅藻藻华的新记录种

2016年5月4日—10日, 海南省海口市红城湖发生了一起硅藻藻华。为明确该起藻华的肇事生物, 于藻华期间采集了水体样品, 经过光镜和电镜下的形态学观察, 确认藻华原因种为微小辐环藻Actinocyclus exiguus Fryxell & Semina, 该种是我国硅藻的新记录种, 其藻华在我国也是首次报道。微小辐环藻隶属于中心纲硅藻, 细胞单独生活或形成胶质状群体, 细胞个体较小, 壳面直径为6.4~11.1μm, 有2个或3个壳缘唇形突, 壳缘处具有眼斑结构。水体中丰富的氨氮(平均值为2880μg•L^-1)和较高的水温(31℃)条件可能是藻华事件的环境诱因。藻华事件导致红城湖40余吨花鰶死亡。经过鱼体检测, 初步排除因为藻毒素、鱼鳃机械性损伤或水体缺氧而致死的可能, 水体盐度剧烈变化等物理应激反应导致鱼类死亡的可能性较大。     

Distribution pattern of pelagic amphipods and its affecting facors in the East China Sea

1 IntroductionAmphipoda, an order of marine pelagic shell-fish, belongs to class Crustacea, subclass Malacost-raca (Chen and Shi,2002). Species of this ordercan be found all over the world, especially in tropi-cal and subtropical oceans. As fish diets, th…     

1998年春季珠江口海域大规模赤潮原因生物的形态分类和生物学特征Ⅲ

对1998年4月22—24日采集于广东珠江口大规模赤潮海域之一的深圳湾的活体水样和福尔马林固定水样进行赤潮原因生物的形态分类和群落构成研究。结果发现，深圳湾赤潮水样里仍以甲藻为主，但硅藻也具相当的数量。其中，最占优种为无纹螺沟藻(Gyrodiniuminstriatum),其最高密度为3.6×10     

The effect of the causative algae of large-scale HAB in the East China Sea on egg hatching of Argopecten irradians, and population growth of Brachionus plicatilis and Moina mongolica

The impacts of Prorocentrum donghaiense Lu and Alexandrium catenella Balech, causative species of the large-scale HAB in the East China Sea, were studied under laboratory conditions. According to bloom densities, the effects of monoculture and mixture of the two species were examined on the egg-hatching success of Argopecten irradians Lamarck, and the population growth of Brachionus plicatilis Müller and Moina mongolica Daday. The results showed that monoculture of A. catenella had a significant inhibition on the egg hatching success of A. irradians, and the population growth of B. plicatilis and M. mongolica. The median effective densities (ED_50) inhibiting the egg hatching success of A. irradians for 24 h and the population growth of B. plicatilis and M. mongolica for 96 h were 800, 630, and 2 400 cells/cm3, respectively. Monoculture of P. donghaiense has no such inhibitory effect on the egg hatching success of A. irradians; P. donghaiense at lower suitable densities could sustain the population growth of B. plicatilis (1×104~3×104cells/cm3) and M. mongolica (2×104~5×104cells/cm3); P. donghaiense at higher densities had significantly adverse effect on the population growth of B. plicatilis (4×104~10×104cells/cm3) and M. mongolica (10×104cells/cm3). When the two algae were mixed according to bloom densities, P. donghaiense at suitable densities to some extent could decrease the toxicity of A. catenella to B. plicatilis and M. mongolica. The results indicated that the large-scale HAB in the East China Sea could have adverse effect on zooplankton, and might further influence the marine ecosystem, especially when there was also Alexandrium bloom.     

东海陆架晚第四纪沉积硅藻及其古海洋学意义

本文对东海陆架DG9617岩芯沉积硅藻进行了研究，共分析鉴定出97种和变种，有近10种硅藻在岩芯中连续分布，且有较高的含量，而其余种类含量极低，仅零星检出。根据该岩芯中产出硅藻种类、含量及硅藻丰度变化特征自下而上共划分出3个硅藻组合带及5个亚带。结合孢粉资料，对产出3个不同硅藻带岩芯的地层年代进行了对比研究，表明该岩芯所代表的地层年代为中－晚全新世，硅藻I组合带大致为大西洋期的沉积，硅藻Ⅱ组合带应为亚北方期的产物，而硅藻Ⅲ组合带与亚大西洋期对应。文中并对不同硅藻组合带产出时的古海洋环境进行了初步探讨。     

水团相互作用与东海高密水环流的演变

本文利用水文和海流观测资料，从水团相互作用去研究东海高密水及其环流的演变。获得如下一些结果：东海高密水冬季形成于东海中部陆架混合水中，入春以后水团挤压，高密水显得更为突出，入秋后高密水变性，东海中部陆架混合水重新形成；东海高密水核心区可形成气旋环流，从冬到秋经历了一个弱—强—弱的演变过程。海流观测结果证实这个环流是存在的；在东海高密水南侧存在较明显的密度锋，从冬到秋它也经历了一个弱—强—弱的演变过程；水团分析发现，各种与主体分离的混合水从春到夏可在高密水核心周围组合成一个环，从而进一步印证了这个高密水环流的存在     

秋冬季东海陆架区浮游纤毛虫的生态分布特点

于2006年11月19日至12月23日(秋季)和2007年2月22日至3月11日(冬季)在东海陆架区(25°-33°N,12°-127°30'E)的6个断面(E1-E6)调查分析了浮游生活的寡毛目纤毛虫的生态分布特点.结果表明:秋季纤毛虫丰度为0～1 795个/dm<'3>,生物量(C)为0～2.36 μg/dm<'3...     

Species composition,diversity and density of plagic Ostracoda in the East China Sea

On the basis of seasonal investigations at 23°30'~33°00'N,118°30'~128°00'E of the East China Sea during 1997~2000,dynamics on the density and diversity of Ostracoda was discussed.Results showed that totally 26 species were identified.The Ostracoda diversity was opposite to the change of its density in most seasons which reflected an uneven assignment of Ostracoda density among its different species.The Ostracoda density was 0.70 ind./m3 in spring,1.72 ind./m3 in summer,2.57 ind./m3 in autumn and 0.90 ind./m3 in winter.Euconchoecia chierchiae in spring and winter,Euconchoecia maimai in summer and Cypridina dentata in autumn were main dominant species in each season.The Ostracoda density did not show an obvious linear relationship with the hydrologic factors in summer and autumn,but was related to the surface salinity in spring and the surface temperature in winter.Its high density areas mainly distributed in the north offshore in all the seasons while in the south offshore in winter and in spring,and the south nearshore in summer and autumn,implied the zooplankton was a typical warm water animal,whose high density distribution in autumn were located in a similar position to Todarodes pacificus,Navodon Septentrionalis,Scomber japonicus and other fishes in the sea,so as to be an important indicator for fishing ground.The main species dominating in Ostracoda now are different from the species twenty years ago probably attributes to global warming.