夏季东海渔场鲐鱼产量与海洋环境因子的关系

根据2002～2004年7～9月我国东海灯光围网渔业生产统计数据,结合卫星遥感获取的海表面温度(Sea surface temperature, SST)、叶绿素a浓度及海面高度数据(Sea surface height,SSH),分析鲐鱼渔场分布与其SST、叶绿素a浓度和SSH之间的关系.统计各月鲐鱼产量在SST、叶绿素a浓度上的频次分布,以确定各月中心渔场的最适SST和叶绿素a浓度范围,并对不同月份鲐鱼产量与SST和叶绿素a浓度关系进行分析和比较.利用Marine Explore4.0软件将每日鲐鱼产量和SSH图像进行空间展布,分析中心渔场形成与SSH分布的内在规律.研究结果显示,鲐鱼产量和当年SST成正比,东海SST的高低基本上决定了当年鲐鱼产量的高低,但并未发现叶绿素a浓度越高渔获产量也越高的规律,说明叶绿素a浓度并非鲐鱼渔场形成的最主要因素.夏季东海SST、叶绿素a浓度分布状况及其分布的季节变化决定了夏季东海鲐鱼作业渔场在东海南部和北部适宜SST、叶绿素a浓度不同的范围,但各年渔场SST以及叶绿素a浓度分布的总体趋势一致,鲐鱼产量集中分布在叶绿素a浓度较低、SST较高的东海南部渔场和叶绿素a浓度较高、SST较低的东海北部长江口渔场:7、8月鲐鱼中心渔场分布在东海南部海域,最适SST分别为27～29 ℃和28～30 ℃,最适叶绿素a浓度均为0.10～0.30 mg/m3;9月东海南部渔场最适SST为27～28 ℃,最适叶绿素a浓度为0.10～0.30 mg/m3,东海北部渔场最适SST为26～27 ℃,最适叶绿素a浓度为1.00～3.00 mg/m3.鲐鱼渔场和SSH之间有很好的匹配关系,中心鱼场通常位于SSH极大值和极小值交汇的海域、并靠近极大值海域一侧,即出现在冷水团和暖水团交汇区靠近暖水团一侧.研究表明,渔场最适SST和叶绿素a浓度以及SSH作为确定潜在中心渔场的指标各具优势,将三者结合、综合分析,预报潜在渔场的位置更为可靠.     

西北太平洋鲐鱼渔场的时空分布及其与海表温度和叶绿素浓度的关系

鲐鱼(Scomber japonicus)是西北太平洋的重要捕捞对象,其分布易受环境变化的影响。为定量分析海表温度和叶绿素浓度等影响因子对渔场分布的作用,文章采用产量重心、地统计插值和广义加性模型等方法,结合2017年西北太平洋2艘灯光敷网渔船的渔捞日志和海洋环境数据,探究该海域的渔场分布变化。研究结果表明：鲐鱼产量和单位捕捞努力量渔获量（CPUE）呈先上升后下降的趋势,其中7月的产量最高,9月的CPUE最高;产量重心于4-9月由SW方向向NE方向移动,并于9-12月返回SW方向;鲐鱼渔场的最适海表温度为14℃～16℃,最适叶绿素a浓度为0.4～1.0 mg/m3;叶绿素a浓度对渔场分布无显著影响,可能与鲐鱼摄食对象的特性有关。     

烟、威海区鲐鱼渔场中浮游动物的昼夜垂直分布

1953年至1957年,在烟、威海区鲐鱼渔场中曾进行了一次渔场自然环境和鲐鱼生活习性的翻查(参阅朱树屏1959年)。该项工作是在黄渤海经济鱼类资源调查委查会领导下进行的,作者等参加了调查中的浮游生物和鲐鱼食物方面的工作。本文所报告的就是调查所得的一部分结果。     

基于提升回归树的东、黄海鲐鱼渔场预报

为提高东、黄海鲐鱼渔场预报准确率、降低渔业生产成本,研究提出了一种基于提升回归树的渔场预报模型。研究采用2003—2010年我国大型灯光围网渔捞日志数据,以有网次记录的小渔区为渔场,以渔捞日志未记录的区域作为背景场随机选择假定非渔场数据,以海表水温等环境因子作为预测变量构建东、黄海鲐鱼渔场预报模型并以2011年的实际作业记录对预报模型进行精度验证。验证计算得到预报模型的AUC(area under receiver operating curve)值为0.897,表明模型的预报精度较高。模型的空间预测结果表明,预报渔场与实际作业位置基本吻合,其位置移动也与实际情况相符。这表明基于提升回归树的渔场预报模型可以用来进行东、黄海鲐鱼渔场的预报。     

基于案例推理的东海区鲐鱼中心渔场预报

根据1998～2005年的东海区上海、宁波、江苏和舟山四大渔业公司的鲐鱼(Pneumatophorus japonicus)生产统计数据以及同期的卫星资料反演的海表温度、叶绿素a浓度数据,利用案例推理方法,设定了上级结果的相似距对下级检索的影响权重因子,进一步研究渔场渔情的分析预报.通过试验性预报实例的预报结果与实际情况比较表明,预测精度达到75%,可以较好地反映出渔场的分布,为渔业资源的开发利用服务.     

海表水温变动对东、黄海鲐鱼栖息地分布的影响

海表水温(SST)通常是表征鱼类栖息地分布的主要指标。本文根据1999—2007年我国大型灯光围网的鲐鱼生产统计数据,结合海洋遥感获得的SST,分析了渔汛期间鲐鱼栖息地的适宜SST范围,探讨了SST变动情况下鲐鱼栖息地的变化趋势。研究结果表明,东、黄海鲐鱼7—12月的适宜SST范围为15~30℃。根据政府气候变化专门委员会(IPCC)第四份评估报告,本文拟定4种SST上升的情况,即(1)每月平均SST+0.5℃;(2)每月平均SST+1℃;(3)每月平均SST+2℃;(4)每月平均SST+4℃。结果显示,东、黄海鲐鱼的潜在栖息有明显向北移动的趋势,并且栖息地面积逐渐减小。研究认为,全球气候变化引起的SST上升,可能会对近海鲐鱼栖息地造成严重的影响。     

东、黄海围网渔场鲐鲹鱼产量的年际变动

根据1998～2002年我国主要渔业公司灯光围网船在东、黄海的生产统计资料,利用Marine Explorer4.0软件进行渔场分布绘制和年际比较,利用空间距离聚类法对南、北两大渔场的产量重心年际变化进行比较.结果表明,高产量渔场主要集中在南部的26°～28°N、122°～124°E和北部的32°～38°N、123°～125°E海域.年际间渔场分布及其产量重心有所变动,北部渔场分布范围较大.渔场产量重心分布变化与海洋环境条件存在明显的关系,1998年6～7月由于沿岸冲淡水势力较强,造成了7月份围网渔场产量重心明显向东偏移.     

基于个体模型的东海鲐鱼渔场形成机制研究

鲐鱼Scomber japonicus资源丰富,在我国近海渔业中占有重要地位。其渔场的形成受海洋环境的制约,本文确定鲐鱼运动和物理环境之间的响应关系,建立起了基于个体的东海鲐鱼生长洄游模型。结果显示,鲐鱼集群分布与捕捞生产渔场基本吻合,鲐鱼聚集主要受台湾暖流、大陆沿岸水、黑潮影响,往往集群在一定温度范围内并在冷暖交汇区温盐梯度大偏暖水一侧。在台湾暖流和沿岸水交汇的锋面附近、台湾暖流暖水舌前端、黑潮与中国大陆沿岸水形成的潮境区域均有大量的鲐鱼聚集,并形成渔场。产卵位置的变动使偏西产卵位置的鲐鱼由于受台湾暖流影响较大,鲐鱼会呈长带状大量聚集在台湾暖流和沿岸水的锋面附近,并使在台湾暖流暖水舌前端的聚集数量增多,而偏东的产卵的鲐鱼受黑潮影响较大,聚集分布范围较大,会使黑潮形成的锋面附近聚集数量增多,而使台湾暖水舌的前端的聚集量减少。正常产卵位置在生存率方面是最佳产卵位置。研究表明鲐鱼所处空间位置不同,会影响其集群的位置,用数值模型验证了物理环境会对鲐鱼的洄游和渔场的形成产生影响。     

台湾海峡鲐鱼食性的初步研究

一、前言鲐鱼Pneumatophorus japonieus为暖水性中上层鱼类,每年进行季节性洄游,游泳能力强,速度快,春夏时多栖息于水温和盐度较高、透明度大、潮流较缓、风浪较小的海区产卵索饵。此时,也是台湾海峡生产鲐鱼的旺季,有较多产量,有一定的经济价值。本文是一次对台湾海峡的鲐鱼食性进行较详尽的研究,现整理报导如下,以供参考。     

东海北部鲐鲹鱼渔场水文特征的统计学研究

东海北部是鲐鱼主要渔场之一 ,研究其水文及其变化特征对于掌握鲐鱼中心渔场的时空变化规律、指导渔业生产、合理利用海洋渔业资源具有重要意义。根据 1 987— 2 0 0 1年在 2 9°— 32°N、1 2 4 5°E以西海域的海洋环境调查资料和鲐鱼渔场资料 ,在GIS平台上 ,用最优隶属模型划分水团 ,并研究渔场的水团和温、盐跃层特性及其月、年变化之间的相关性 ,用于渔情预报。研究表明 ,用最优隶属模糊聚类方法划分该海域水团的结果与以往的研究结果比较一致 ;鲐鱼渔情与该区域水团第一强度、第二强度之间显示了一定的相关性 ;用稳健统计学方法 ,可确定中心渔场的底层、鱼类栖息水层的温盐范围及其聚类中心值 ;鲐鱼渔情、渔场与水文跃层的关系密切。     

Role of Meso-Scale Eddies on Circulation in the South Eastern Arabian Sea in 2009

Spatial current data were collected from South eastern Arabian Sea during July 2009 (summer monsoon) and December 2009 (winter monsoon) using the vessel mounted Acoustic Doppler Current Profiler (ADCP). During July 2009, observed ADCP currents were flowing southward along 75°E longitude with a complex pattern near the coast. During winter (December 2009), an anti-clockwise rotation of currents was observed in the study region, with its eastern arm along the southwest coast of India. The circulation pattern observed during the two seasons from ADCP measured data does not seem to follow any pattern described in climatology. To investigate this aspect, the geostrophic currents were computed utilizing the multi-mission altimeter sea surface height anomaly data for the corresponding months. The analysis of geostrophic currents indicates the presence of multiple eddies embedded in the Laccadive Low (LL) /Laccadive High (LH). Our present study shows that the meso-scale eddies embedded in the LL and LH play a significant role in deviating the observed circulation from climatology in this region. In addition, generating mechanisms of these eddies are addressed to substantiate our findings. The formation of these eddies is attributed to the local wind force during July 2009 and the enhanced baroclinic instability during December 2009.     

Study on spatial and temporal distribution of planktonic amphipoda in the East China Sea

Quantitative distribution of planktonic amphipoda in the East China Sea is analyzed and the relation with environmental factors and mackerel and scad fishing grounds is studied. The result shows that the characteristic of biomass is great seasonal and interannual variety during the passing three decades. The distribution of planktonic amphipoda basically reflects the movement, decay and intensification of the different water systems in the survey area.     

大鹏湾浮游细菌时空分布与环境因子的关系

应用荧光显微镜计数法,研究了大鹏湾海域细菌丰度时空分布特征,探讨了其与温度、溶解氧、叶绿素a、氨盐、硝酸盐和磷酸盐之间的关系.结果表明,大鹏湾全年细菌丰度介于1.40x10<'8>-24.43x10<'8>个L<'-1>之间.各季节细菌丰度高低依次为:夏季、春季、秋季、冬季.浮游细菌的水平分布呈现近岸较高、离岸逐渐减少,自大鹏湾西部湾顶向东部湾口逐渐减少的特征.除了夏季,温度与浮游细菌呈显著正相关(P<0.05),是浮游细菌的主要控制因子;溶解氧与浮游细菌全年呈显著负相关(春、夏季P<0.01,秋冬季P<0.05);叶绿素a除了春季外其他季节与浮游细菌相关性非常显著(P<0.01),是浮游细菌的主要调控因子;无机营养盐中,氨盐和磷酸盐全年与浮游细菌丰度呈高度显著正相关(P<0.01):对浮游细菌丰度具有调控作用,硝态氮在冬季对浮游细菌丰度有显著调控作用.     

Study on spatial and temporal distribution of planktonic amphipoda in the East China Sea

Quantitative distribution of planktonic amphipoda in the East China Sea is analyzed and the relation with environmental factors and mackerel and scad fishing grounds is studied. The result shows that the characteristic of biomass is great seasonal and interannual variety during the passing three decades. The distribution of planktonic amphipoda basically reflects the movement, decay and intensification of the different water systems in the survey area.     

东海浮游端足类数量的时空分布特征

分析了东海端足类数量分布的时空变化,并就其与环境因素及鲐鯵渔场的关系进行了初步探讨,结果显示本区端足类数量季节变化和年际变化显著,其分布状况与黄海冷水、江浙沿岸流、台湾暖流以及黑潮在本区运动消长有关,与鲐鯵渔场分布有着密切关系.     

Meiofauna of the western continental shelf of India,Arabian Sea

Meiofaunal standing stock and nematode community structure were investigated in the western continental shelf of India by collecting samples from every degree square of the shelf during two cruises of the FORV (Fishery and Oceanographic Research Vessel) Sagar Sampada, conducted in 1998 and 2001. Samples were collected from 30, 50, 100 and 200 m depths using a Smith Mc Intyre grab. Meiofaunal density ranged from 8 Ind. 10 cm⁻² to 1208 Ind. 10 cm⁻² and biomass from 0.07 mg 10 cm⁻² to 6.11 mg 10 cm⁻². Nematodes were the dominant meiofaunal group, contributing 88% of the density and 44% of the biomass. Harpacticoid copepods were the second important taxa, contributing 8% of both biomass and density. Altogether, 154 species of nematodes belonging to 28 families were recorded from the study area. Numerically, Desmodora spp., Dorylaimopsis sp., Tricoma spp., Theristus spp. and Halalaimus spp. were the dominant species. In general, there was a decrease in biomass and density of meiofauna and species diversity of nematodes with increase in depth. There was a 67% drop in species number from 51 to 100 m (106 species) to the shelf edge (35 species). Species richness and diversity indices showed consistent decrease with depth. The species dominance index was higher below 150 m depth. ANOSIM (from PRIMER) showed a significant difference between the nematodes of the near shore and shelf edge. Latitudinal variation was observed only in the number of nematode species. Biomass and abundance of nematodes were found to increase from coarse to fine sediment, while copepods showed an opposite trend. Multivariate analyses of nematode communities did not reveal any latitudinal or substratum differences. Variables such as depth, latitude, organic matter (OM) and amount of clay were the most relevant parameters influencing the biomass and density of meiofauna, while depth and temperature were the important parameters explaining the distribution of the nematode communities along the western Indian shelf.     

The stratigraphic evolution of the Indus Fan and the history of sedimentation in the Arabian Sea

The Indus Fan records the erosion of the western Himalayas and Karakoram since India began to collide with Asia during the Eocene, 50 Ma. Multi-channel seismic reflection data from the northern Arabian Sea correlated to industrial well Indus Marine A-1 on the Pakistan Shelf show that sedimentation patterns are variable through time, reflecting preferential sedimentation in deep water during periods of lower sea-level (e.g., middle Miocene, Pleistocene), the diversion of sediment toward the east following uplift of the Murray Ridge, and the autocyclic switching of fan lobes. Individual channel-levee systems are estimated to have been constructed over periods of 10⁵–10⁶ yr during the Late Miocene. Sediment velocities derived from sonobuoys and multi-channel stacking velocities allow sections to be time-depth converted and then backstripped to calculate sediment budgets through time. The middle Miocene is the period of most rapid accumulation, probably reflecting surface uplift in the source regions and strengthening of the monsoon at that time. Increasing sedimentation during the Pleistocene, after a late Miocene-Pliocene minimum, is apparently caused by faster erosion during intense glaciation. The sediment-unloaded geometry of the basement under the Pakistan Shelf shows a steep gradient, similar to the continent-ocean transition seen at other rifted volcanic margins, with basement depths on the oceanward side indistinguishable from oceanic crust. Consequently we suggest that the continent-ocean transition is located close to the present shelf break, rather than >350 km to the south, as previously proposed.     

阿拉伯海热带气旋生成特征分析

利用印度气象局（India Meteorological Department,IMD）、国际气候管理最佳路径档案库（International Best Track Archive for Climate Stewardship,IBTrACS）提供的1982—2020年阿拉伯海热带气旋路径资料,美国国家环境预报中心（National Centers for Environmental Prediction,NCEP）再分析资料,对近39 a阿拉伯海热带气旋源地和路径特征、活跃区域、频数及气旋累积能量（accumulated cyclone energy,ACE）指数的季节特征和年际变化特征进行分析,并结合环境因素,说明其物理成因。结果表明：阿拉伯海热带气旋多发于10°~25°N,65°~75°E海域,5—6月、9—12月发生频数较高且强度较强,1—4月、7—8月发生频数较低且气旋近中心最大风速均小于35 kn;频数的季节变化主要受控于垂直风切变要素;阿拉伯海热带气旋发生频数和ACE近年有上升趋势,年际变化主要受控于海面温度（sea surface temperature,SST）和850 hPa相对湿度要素。     

Impact of oxygen-depleted water on the vertical distribution of chaetognaths in the northeastern Arabian Sea

The influence of a thick layer of oxygen-depleted water (<0.2 ml l⁻¹) on the abundance and distribution of chaetognaths was investigated in the northeastern Arabian Sea (NEAS), a natural oxygen-deficient system in the global ocean. The species and maturity stage-wise distribution of this group were studied at five discrete depths down to 1000 m. A total of 22 species belonging to four genera were observed, and the genus Sagitta dominated, representing 60% (500-1000 m) to 89% (Mixed layer depth) of the total chaetognath population. Based on their vertical distribution limits, four groups were recognised, as follows: I: species abundant in surface water with a maximum distribution limit up to 300 m; II: species confined mainly to deeper waters (>500 m); III: species present throughout the water column (0-1000 m); and IV: species present in most layers, but with a preference for a specific depth stratum. A positive correlation (P<0.01) was observed in the abundance of chaetognaths and their main prey copepods, emphasising the strong trophic relationship between these groups. It was found that the intensely oxygen-deficient waters of the NEAS play a crucial role in the vertical distribution and abundance of chaetognath species of all four genera. This report presents information on the maturity stages and ontogenetic migration of this important planktonic group in relation to the oxygen-depleted water in the study region for the first time. The results obtained are also important for understanding the biological processes associated with a major oxygen minimum zone (OMZ) in the global ocean.     

Monsoon-driven biogeochemical processes in the Arabian Sea

Although it is nominally a tropical locale, the semiannual wind reversals associated with the Monsoon system of the Arabian Sea result annually in two distinct periods of elevated biological activity. While in both cases monsoonal forcing drives surface layer nutrient enrichment that supports increased rates of primary productivity, fundamentally different entrainment mechanisms are operating in summer (Southwest) and winter (Northeast) Monsoons. Moreover, the intervening intermonsoon periods, during which the region relaxes toward oligotrophic conditions more typical of tropical environments, provide a stark contrast to the dynamic biogeochemical activity of the monsoons. The resulting spatial and temporal variability is great and provides a significant challenge for ship-based surveys attempting to characterize the physical and biogeochemical environments of the region. This was especially true for expeditions in the pre-satellite era.Here, we present an overview of the dynamical response to seasonal monsoonal forcing and the characteristics of the physical environment that fundamentally drive regional biogeochemical variability. We then review past observations of the biological distributions that provided our initial insights into the pelagic system of the Arabian Sea. These evolved through the 1980s as additional methodologies, in particular the first synoptic ocean color distributions gathered by the Coastal Zone Color Scanner, became available. Through analyses of these observations and the first large-scale physical–biogeochemical modeling attempts, a pre-JGOFS understanding of the Arabian Sea emerged. During the 1990s, the in situ and remotely sensed observational databases were significantly extended by regional JGOFS activities and the onset of Sea-viewing Wide Field-of-View Sensor ocean color measurements. Analyses of these new data and coupled physical–biogeochemical models have already advanced our understanding and have led to either an amplification or revision of the pre-JGOFS paradigms. Our understanding of this complex and variable ocean region is still evolving. Nonetheless, we have a much better understanding of time–space variability of biogeochemical properties in the Arabian Sea and much deeper insights about the physical and biological factors that drive them, as well as a number of challenging new directions to pursue.