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.     

Seasonal distribution of Calanus sinicus (Copepoda, Crustacea) in the East China Sea

On the basis of the four-season investigation in 23°30′~33°N and 118°30′~128°E of the East China Sea from 1997 to 2000, the seasonal distribution of Calanus sinicus was studied with aggregation intensity, regression contribution and other statistical methods. It was inferred that C. sinicus’s predominance presented from winter to summer, especially in spring and summer, because its dominance amounted to 0.62 and 0.29 respectively. The percent of its abundance in copepod abundance was 76.71% in summer, greater than 66.60% in spring, greater than 19.02% in winter, greater than 4.02% in autumn. The occurrence frequency in winter and spring was 83.08% and 93.89%, higher than that in summer and autumn, 76.71% and 73.87%. Compared with other dominant species of copepods, C. sinicus’s contribution to the copepod abundance was obviously greater than that of the other species in winter, summer and spring, but smaller in autumn. C. sinicus tended to have an aggregated distribution. The clumping index peaked in summer (50.19), followed in spring (19.60), declined in autumn (13.18) and was the lowest in winter (3.04). The abundance changed in different seasons and areas, relating to temperature but not salinity in spring and autumn, to salinity but not temperature in summer; to neither temperature nor salinity in winter. In spring and summer, its high abundance area was often located in the mixed water mass formed by the Taiwan Warm Current, the Huanghai Sea Cold Water Mass, the coastal water masses and the Changjiang Dilute Water. In spring and autumn, its abundance was affected by the warm current, as well as the runoff from continental rivers affected it in summer. It can be inferred that C. sinicus was adapted to wide salinity and temperature, as a euryhalinous and eurythermous species in the East China Sea.     

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…     

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…     

东海浮游翼足类(Pteropods)数量分布的研究

根据1997～2000年东海海域23°30'～33°00'N,118°30'～128°00'E的4个季节海洋调查资料,运用定量、定性方法,探讨了东海浮游翼足类总丰度的平面分布、季节变化及变化的动力学机制.结果表明,东海翼足类总丰度和出现频率有明显的季节变化,均为秋季最高,夏季次之,春季最低;总丰度在各个季节基本上呈东海南部高于北部、外海高于近海的分布趋势;春季的尖笔帽螺(Creseis acicula)、夏季的锥笔帽螺(Creseis virgula)、秋季的蝴蝶螺(Desmopterus papilio)和冬季的马蹄螔螺(Limacina trochiformis)是导致总丰度季节变化的最主要的种类;冬、春和夏3个季节丰度变化及4季总丰度的变化同表层或10m层水温有非常显著的线性相关关系,与底层温度及盐度的相关关系不显著.夏季翼足类高丰度区位于台湾暖流与黑潮暖流的分支处;从夏季到秋季,翼足类随着台湾暖流向北扩展,并在与长江冲淡水,闽浙沿岸水团,黄海水团等交汇处形成高丰度(大于500×10-2个/m3)和较高丰度(250×10-2～500×10-2个/m3)分布区.水温和海流是影响东海翼足类总丰度分布的主要环境因素.     

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.     

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.     

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     

东海海樽类数量分布及与环境的关系

提要根据1997—2000年东海23°30′—33°00′N、118°30′—128°00′E海域4个季节海洋调查资料,采用方差贡献和逐步回归分析方法探讨东海海樽类的数量变化和相应的动力学。结果表明,海樽类是东海浮游动物第二大类群,在数量上仅次于桡足类,其丰度春季最高,夏季次之,冬季最低;冬、春和夏季的东方双尾纽鳃樽(Thalia orientalis)和冬、秋季的小齿海樽(Doliolum denticulatum)是影响海樽类数量分布的主要优势种;海樽类高丰度区常位于暖流与各水团交汇处的偏暖流一侧,其数量变化的动力主要来自暖流势力的消长。海樽类在东海出现率较低,集群性强,较高丰度的分布仅局限在暖流势力范围内,其高丰度水域是东海暖流锋面的一个重要标志。     

渤海西南部小型水母群落特征与环境因子相关性研究

根据2020年8月至2021年5月对渤海西南部浮游动物调查的4个航次数据,分析该海域水螅水母、栉水母群落结构和季节变化特征,讨论了环境因子对小型水母丰度的影响。研究发现,渤海西南部小型水母种类组成和丰度分布存在季节变化,全年调查共发现小型水母13种,11种水螅水母、2种栉水母;春、夏、秋、冬该海域水母种数分别为4种、9种、7种和2种,丰度均值分别为30.74 ind./m3、30.78 ind./m3、12.08 ind./m3、0.57 ind./m3;优势种为嵊山秀氏水母（Sugiura chengshanense）、八斑芮氏水母（Rathkea octopunctata）、锡兰和平水母（Eirene ceylonensis）、半球美螅水母（Clytia hemisphaerica）、球型侧腕水母（Pleurobrachia globosa）,优势种季节更替率平均为91.67%,呈现明显季节演替。水温和盐度是影响渤海西南部小型水母丰度季节变化的主要环境因子,春季水温回升及适宜营养盐含量促进小型水母生长繁殖,夏季桡足类为小型水母提供了丰富的饵料促进其生长,秋季群落主要受盐度的影响。根...     

舟山群岛东侧海域蟹类群落结构及其与环境因子的关系

根据2018年4月(春季)和10月(秋季)在舟山群岛东侧海域(29°10′25.54"～30°45′00"N,122°53′3.88"～124°48′28.31"E)开展的渔业资源底拖网调查所获得的蟹类数据,研究了该海域蟹类资源的种类组成、优势种、生物多样性等群落结构特征,同时分析了蟹类数量分布及其群落结构与温、盐等环...     

2004—2006年暖水季节闽东沿岸浮游动物主要生态特征比较研究

本文根据2004～2006年闽东沿岸（26°30′00″～27°10′00″N，119°59′40″～120°33′00″E）暖水季节6个航次的浮游动物调查资料，比较分析研究了调查区暖水季节的浮游动物种类组成、数量分布和优势种变化．3年调查结果表明，该海域出现的浮游动物种类数分别为151、127和144种，种类组成变化不大，强额孔雀哲水蚤（Pavocalanus crassirostri）、小拟哲水蚤（Paracalanus parvus）等在各航次中都占据明显优势地位；调查期间该海域的浮游动物群落面貌以近岸暖水种和外海热带种为主，这两类生态类群的浮游动物构成本海区的主要优势类群；生物量分布不均匀，总体平面分布趋势是：北高南低，从沿岸到近海，浮游动物生物量随盐度上升而下降；优势种分布极不均匀，聚块现象明显．     

东海浮游介形类(Ostracods)分布特征

根据1997~2000年东海(23°30'~33°00'N,118°30'~128°00'E)海域四季海洋调查资料,探讨了东海浮游介形类分布特征及与环境的关系.结果表明:东海浮游介形类丰度占浮游动物总丰度的3.47%;春、夏、秋和冬四季平均丰度分别为0.70,1.72,2.57和0.90个/m3;冬春季的短棒真浮萤(Euconchoecia chierchiae),夏季的后圆真浮萤(Euconchoecia maimai)和秋季的齿形海萤(Cypridi-na dentata)分别是各季的主要优势种;夏、秋季介形类总丰度与水文环境因子的线性相关性不显著,春季与表层盐度相关,冬季与表层温度相关.东海北部外海四季均有介形类高丰度区出现,但在东海北部近海长江口及其邻近舟山水域,介形类数量相对较低.在东海南部,冬春季高丰度区位于外海,夏秋季在近海.东海浮游介形类基本上是一大类较为典型的暖水性且具有集群行为的海洋浮游动物.介形类秋季高丰度区和较高丰度区的分布与太平洋褶柔鱼(Todarodes pacificus)、绿鳍马面鲀(Navodon Septentrionalis)、鲐鯵鱼类等渔场的位置基本一致,在渔业上有重要的意义.     

舟山渔场及邻近海域蟹类种类组成和时空分布

根据2006年8月、2007年1月、5月和11月4个季节在舟山渔场及邻近海域(29°30′N—32°00′N,127°E以西)开展海洋生态系统综合调查时所获得的蟹类调查资料,以渔获率作为蟹类数量指标分析该海域蟹类资源状况,包括种类组成、数量分布和时空变化。结果表明,本次舟山渔场及邻近海域调查共得蟹类种类43种,隶属于10科、21属。优势种类为细点圆趾蟹、双斑蟳、三疣梭子蟹、日本蟳、红星梭子蟹、红线黎明蟹,以上6种蟹类占蟹类总渔获量的94.58%。本次调查与20世纪90年代末在东海大陆架海域的蟹类资源调查结果相比,蟹类种类组成和优势种变化不大。从蟹类渔获率来看,秋季以舟山渔场最高,夏季以江外渔场最高,蟹类资源密集区主要位于长江口渔场和舟山渔场北部。     

黄海南部和东海小黄鱼资源分布差异性研究

根据2006年6月～2007年4月黄海南部和东海底拖网监测调查资料,比较分析了2个海域小黄鱼资源密度指数(CPUE)分布、环境因子特征、CPUE与环境因子相关关系的差异.研究结果表明,黄海南部和东海小黄鱼资源密度指数分布除了秋季分布有显著差异之外(t′_((33))=2.69,P=0.011),其余季节分布均无显著差异(春季:t′_((43))=1.68,P=0.104;夏季:t′_((60))=0.31,P=0.756 7;冬季:t′_((43))=1.74,P=0.089);夏季的底层盐度分布和水深分布没有明显差异,在其他季节,黄海南部和东海的底层水温、底层盐度和水深分布等环境特征的差异明显,均达到极显著(P<0.01)或显著(P<0.05)水平;资源密度与环境因子回归分析和AIC模型选择中,2个海域夏季的小黄鱼资源密度受到有显著性影响的环境因子数最多,而冬季受到有显著性影响的环境因子最少.综合推断,黄海南部和东海小黄鱼具有不同空间分布特征和环境分布特征,2个海域的小黄鱼分属于不同种群,但在2个海域交界处有混栖种群.     

长江口及邻近海域浮游动物生物量分布及季节变化

2006年7月—2007年12月,在长江口及邻近海域(29°30′N~32°30′N,120°00′E~127°30′E)布设150个观测站位,进行了4个季节生物、化学和物理海洋学综合调查。根据采集的浮游动物样品的分析鉴定结果及现场环境参数的测定数据,对浮游动物群落生物量分布及季节变化进行了研究。结果表明:长江口及邻近海域浮游动物生物量有明显的季节变化,主要表现为:春季>夏季>秋季>冬季。中华哲水蚤(Calanussinicus)、双生水母(Diphyeschamissonis)、百陶带箭虫(Zonosagittabedoti)和中华假磷虾(Pseudeuphausiasinica)是长江口及邻近海域浮游动物生物量的主要贡献者。化学营养盐是影响长江口及邻近海域浮游动物生物量分布的主要环境因素,除此以外,其它环境因子在不同季节对浮游动物生物量的影响存在差异。春季,温度和盐度是影响浮游动物生物量的主要因素;夏季,温度、溶解氧和叶绿素a是影响浮游动物生物量的主要因素;秋季,盐度、溶解氧和悬浮颗粒物是影响浮游动物生物量的主要因素。冬季,环境因子对浮游动物生物量影响不明显。     

2011年长江口-东海P-PN断面碳酸盐体系参数的季节分布特征及影响因素

海水碳酸盐体系参数是反映碳循环调控机理和季节性酸化过程的重要海水化学参数.本文根据2011年3月、7月、11月和12月4个不同季节航次获取的长江口海域海水碳酸盐体系参数,探讨了长江口-东海P断面溶解无机碳(DIC)和总碱度(T A)的空间分布特征及其影响因素.结果表明:内陆架区,DIC和T A的平均值均表现为:夏季<秋季<冬季<春季;垂直分布上,夏季和秋季受长江冲淡水影响出现层化现象,春季和冬季均垂直混合较均匀.东海内陆架DIC与温度和DO呈显著负相关;T A则受温度和DO变化影响较小,与盐度呈正相关.结合2011年东海外陆架的PN断面数据分析,DIC和pH分别与表观耗氧量(AOU)呈显著正相关和负相关,东海外陆架的pH/AOU的斜率为-0.0027 pH/(μmol·kg-1);而内陆架区的pH/AOU的斜率为-0.0018 pH/(μmol·kg-1),低于黑潮次表层水中pH/AOU的斜率.东海内陆架区由于存在季节性的通风作用以及较强的海水碳酸盐体系缓冲能力,底层水体中因有机质耗氧降解导致的季节性酸化信号在一定程度上得到了缓解.     

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

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

Seasonal abundance and distribution of pelagic tunicates (Chordata: Thaliacea) in the central South China Sea

1IntroductionTunicates(Chordata:Thaliacea)are large pe-lagic gelatinous zooplankton.They can be used as in-dicator species for ocean currents and water bodies(Chen et al.,1980;Chen et al.,1988;Lin,1988,1990;Lin and Zhang,1993;Thompson,1948).They also play…     

福建宁德晴川湾海域水母群落特征及其潜在生态风险分析

根据2018年1月(冬季)、4月(春季)、7月(夏季)和11月(秋季)在宁德晴川湾海域浮游动物调查的4个航次数据，分析该海域水母群落结构和季节变化特征，讨论了水母对宁德晴川湾核电站安全生产潜在的风险。结果表明:宁德晴川湾海域水母类种类组成、丰度分布和优势种演替均存在季节变化，春、夏、秋、冬该海域水母种数分别为7种、16种、9种和3种，丰度均值分别为(45.48±8.24)个/m3、(50.26±12.13)个/m3、(3.68±1.91)个/m3和(0.18±0.07)个/m3，首要优势种分别为印度感棒水母(Laodicea indica)、球型侧腕水母(Pleurobrachia globosa)、双生水母(Diphyes chamissonis)和耳状囊水母(Euphysa aurata)，优势种类组成季节演替明显。春季和夏季水母的丰度与浮游动物的总丰度呈极显著相关，在夏季其数量与浮游动物中的桡足类数量呈显著相关(p<0.05，R=0.363)，秋季和冬季水母群落的丰度主要受盐度的影响。秋、冬季该海域盐度、温度均较低，水母的丰度也较低。根据宁德晴川湾核电站附近海域水母分布特征，以水母丰度50 个/m3为风险阈值考虑，夏季为潜在高风险季节，需重点关注距核电站冷源取水口5～20 km海域；其次是春季，重点关注距取水口2.5～5 km海域；秋季和冬季基本不会因水母而引起核电站冷源安全事故发生。