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1.
本文旨在查明目前黄河口水域鱼类浮游生物的种类组成和数量变化,为进一步研究鱼类资源早期补充、种群动态以及制定合理的渔业资源养护措施提供基础资料。根据2013年8月、2014年5月在黄河口及其邻近水域进行的鱼卵、仔稚鱼的调查数据,研究了该水域5、8月鱼卵、仔稚鱼的种类组成、数量分布,分析了鱼卵、仔稚鱼优势种数量分布与水温、盐度等环境因子的关系。研究表明,本次调查获得鱼卵25 613粒,隶属于12科13属15种(未定种1种);仔稚鱼369尾,隶属于4科7属9种(未定种1种)。5月鱼卵优势种为日本鳀(Engraulis japonicus)、赤鼻棱鳀(Thryssa chefuensis)和斑鰶(Konosirus punctatus),密集区分布在黄河口北部近岸海域,分布在密集区的种类以日本鳀和赤鼻棱鳀为主;8月鱼卵优势种为短吻红舌鳎(Cynoglossus joyneri)和多鳞鱚(Sillago sihama),其鱼卵主要集中分布于北部近岸海域,南部水域的部分站位也有鱼卵密集,密集区内的种类以短吻红舌鳎和多鳞鱚为主。5月仔稚鱼优势种为矛尾虾虎鱼(Chaeturichthys stigmatias)和赤鼻棱鳀等,仔稚鱼主要集中分布于黄河口南部海域,密集区以赤鼻棱鳀和矛尾虾虎鱼为主;8月仔稚鱼数量极少,无明显优势种。Pearson相关分析表明,除5月赤鼻棱鳀鱼卵数量与表层水温呈显著正相关外,其他优势种鱼卵、仔稚鱼数量与表层水温、表层盐度均无显著相关性。与历史同期调查结果相比,该水域5、8月鱼卵、仔稚鱼的种类组成和数量分布均发生了一定的变化。带鱼(Trichiurus lepturus)、小黄鱼(Larimichthys polyactis)、蓝点马鲛(Scomberomorus niphonius)和鳓(Ilisha elongate)等传统经济鱼类的鱼卵、仔稚鱼少见,以日本鳀、赤鼻棱鳀和斑鰶等小型中上层鱼类为主要优势种;黄姑鱼(Nibea albiflora)、皮氏叫姑鱼(Johnius belangeri)等鱼卵、仔稚鱼密度低。  相似文献   

2.
根据2011年4月、5月与6月对浙江南部沿岸产卵场进行的共3个航次的调查资料,对该海域的鱼卵、仔稚鱼的种类组成和数量分布进行了分析,结果表明,共发现鱼卵、仔稚鱼72个种类,分别隶属11目38科48属。其中鱼卵29种,分别隶属6目18科24属;仔稚鱼55种,分别隶属10目29科40属。4—6月仔稚鱼数量呈逐月递减的趋势,而鱼卵数量6月最多,5月最少。鱼卵优势种4月以斑鰶、棱鱚、小黄鱼与蓝点马鲛为主,5月以斑鰶、鳀、龙头鱼、银鲳、蓝点马鲛与石首鱼科为主,6月以鳀、龙头鱼、多鳞鱚与鲱科鱼类为主;仔稚鱼优势种4月以虾虎鱼类、褐菖鲉与平鲉科为主,5月以鳀、虾虎鱼类、棱鱚、斑鰶与长鳍篮子鱼为主,6月以鳀与虾虎鱼类为主。斑鰶、鲳鱼、小黄鱼、棱鱚、蓝点马鲛与褐菖鲉的产卵盛期为4月,而鳀与龙头鱼的产卵盛期为6月。  相似文献   

3.
蒋玫  李磊  沈新强  全为民 《海洋学报》2014,36(6):131-137
根据2010—2011年春夏季对长江河口及邻近水域进行了仔稚鱼生态调查,应用单元和多元统计方法分析了春夏季长江河口及邻近水域仔稚鱼群落结构。4个航次调查共获得27个种类的仔稚鱼,隶属5目14科。优势种类主要包括鳀Engraulis japonicus、凤鲚Coilia mystus、康氏小公鱼Stolephorus commersonii、鮻Liza haematocheila、黄姑鱼Nibea albiflora、黄鳍刺虎鱼Acanthogobius flavimanus和寡鳞飘鱼Pseudolaubuca engraulis等。Shannon-Weaver指数(H′)在调查周期内的波动幅度较大,且2011年明显低于2010年。仔稚鱼群落结构和多样性指数春季年间较夏季年间差异性显著。调查区夏季群落结构年间相似性不高,春季群落结构格局年际变化则较明显。聚类分析表明,春夏季长江河口近岸水域仔稚鱼群落可划分为2个站位组,分别对应于长江河口淡水水域和长江口咸水水域。淡水水域组群落和咸水水域组群落总丰度与盐度相关性较高。表明盐度可能是造成长江河口仔稚鱼群落结构时空差异性的主要原因。  相似文献   

4.
为了解瓯江口海域鱼卵和仔稚鱼的生态分布现状,分别于2015年4月和10月在该海域开展生态调查。春、秋两季共采集到鱼卵42粒,仔稚鱼295尾;共鉴定出鱼卵和仔稚鱼16种,分别隶属于8目14科15属,其中鲈形目种类最多。春季鱼卵、仔稚鱼物种数和丰度均远高于秋季。春季鱼卵优势种为斑鰶Konosirus punctatus,秋季为舌鳎属未定种Cynoglossus sp.;春季仔稚鱼优势种为鮻Liza haematocheila、花鲈Lateolabrax japonicus和矛尾鰕虎鱼Chaeturichthys stigmatias,秋季为侧带小公鱼属未定种Stolephorus sp.。瓯江口海域春季鱼卵和仔稚鱼的丰度高值区均位于大门岛周围,该海域应在海洋生态红线划定时予以考虑,秋季则相对分散在较外侧海域。春季仔稚鱼数量分布与盐度和营养盐有极显著相关性。与20世纪90年代初相比,该海域的鱼卵、仔稚鱼物种及数量均在发生变化,数量略呈下降趋势。与浙江近岸其他海域相比,瓯江口海域的鱼卵、仔稚鱼数量偏低。  相似文献   

5.
1986年秋日本以南和以东海域仔稚鱼的分布   总被引:2,自引:0,他引:2  
1986年10~11月在日本以南和以东海域的41个测站进行了鱼卵、仔鱼的调查,共采集到996尾仔稚鱼,它们隶属于38科67种,经济鱼类仔鱼稀少,而大洋性发光鱼类仔鱼十分丰富,其中钻光鱼科和灯笼鱼科分别占仔鱼总数的50.50%和32.33%。优势种为细钻光鱼、串灯鱼和西明灯鱼,它们分别占仔鱼总数的25.30%,16.47%和7.53%。仔鱼的丰度在黑潮流轴外侧边缘及其邻近的大洋域最高,在日本以南的沿岸水域占第二位,而在日本以东的混合水域最低。仔鱼丰度与温、盐度之间有显著的正相关关系。  相似文献   

6.
2006年夏季长江口及其邻近水域浮游植物群集   总被引:5,自引:0,他引:5  
根据2006年8月在长江口及其邻近水域(30°30′N~32°30′N,121°E~123°E)39个观测站采集的浮游植物水样,研究了该水域浮游植物群集特征.调查区浮游植物以硅藻和甲藻为主,此外还有少量的金藻、蓝藻和绿藻.浮游植物主要优势物种为脆指管藻(Dactyliosolen fragilissima)和中肋骨条藻(Skeletonema costatum).浮游植物细胞丰度介于0.27~4830.09 cells·mL-1,平均为290.92 cells·mL-1,高值出现在调查区122°30′E~123°E水域,近岸细胞丰度较低.浮游植物细胞丰度的垂直分布特征是随水深增加先增大后减小,最大值出现在10m层.调查区两个断面细胞丰度由沿岸至冲淡水域呈增加趋势,但在调查区靠近外海一侧出现细胞丰度最低值.  相似文献   

7.
福建三沙湾浮性鱼卵和仔、稚鱼的分布   总被引:6,自引:1,他引:6  
戴燕玉 《台湾海峡》2006,25(2):256-261
本文根据1990年2~11月在三沙湾海域分别进行4个季节调查的资料,对三沙湾鱼卵和仔、稚鱼的种类组成、丰度和主要种类的分布进行研究和探讨.结果表明,本海区共出现鱼卵和仔、稚鱼26种,分别隶属于17科22属.在数量上,鱼卵最高值出现在春季(5月),其中鱼卵丰度较高的种类是真鲷、带鱼、鲾和康氏小公鱼等种类.仔稚鱼以夏季丰度最高,并以鰕虎鱼丰度(71.8%)最高.在分布上,鱼卵的丰度以三都岛东北部和东吾洋海域最高,仔稚鱼以三都岛东部最为密集.这表明本海区的鱼类的主要产卵季节是春季和夏季.其数量、分布与水温及桡足类的分布关系密切.  相似文献   

8.
2006年秋季长江口及其邻近水域浮游植物群集   总被引:1,自引:0,他引:1  
赵冉  孙军  白洁 《海洋科学》2010,34(4):32-39
根据2006年11月在长江口及其邻近水域(30°30′N~32°30′N,121°E~123°30′E)39个测站采集的浮游植物水样研究了该水域浮游植物群集特征。调查区浮游植物以硅藻和甲藻为主,此外还有少量的金藻、蓝藻和绿藻。浮游植物细胞丰度介于0.13~59.69个/mL之间,平均为4.39个/mL,主要优势物种为圆海链藻Thalassiosira rotula和骨条藻Skeletonema spp.,调查区两个细胞丰度密集区分别出现在靠近口门以及外海水域。浮游植物细胞在20m层出现最大值。调查区两个典型断面的浮游植物分布特征分别由骨条藻和圆海链藻所刻画。固氮蓝藻铁氏束毛藻Trichodesmium thiebautii主要出现在调查区东部水域表层。根据浮游植物物种和细胞丰度进行聚类分析后,发现存在调查区东部与近岸2个浮游植物分区。  相似文献   

9.
吴光宗 《海洋与湖沼》1989,20(3):217-229
于1985年8月—1986年8月间,在长江口海区(30°45′—32°00′N,124°00′E以西)周年生态调查表明:鳀鱼鱼卵和仔、稚鱼的出现数量,占该区各种鱼卵和仔、稚鱼总量的首位。其中,垂直网采到的鳀卵和仔、稚鱼分别为同网型总量的82.72%和45.90%,而表层网的则分别为82.73%和54.64%。鳀卵出现在全年的4月中旬—10月中旬,以5,6两月为鳀卵集中出现的月份。鳀卵分布区的表层水温为17.0—24.5℃,表层盐度为22.50—30.50‰;122°30′E以东的海区为鳀鱼的主要产卵场,成鱼在该区作自东向西,再折回东部的生殖洄游。 康氏小公鱼卵和仔、稚鱼的出现数量,占调查区第二位。其中在垂直网中的出现数量,分别占卵和仔,稚鱼总量的3.39%和3.48%,表层网的分别为5.12%和6.34%。生殖期在6月中旬—10月中旬,盛期在7—9月。产卵时的最低表层水温在21.0℃以上,适盐广泛。主要产卵场是122°30′E以西的南、北近岸河口浅水区,成鱼生殖时作自南向北的生殖洄游。 两种鱼在调查区的鱼类组成和食物链中占有极为重要的位置,并有着较丰富的资源潜力。  相似文献   

10.
秋季南黄海表层沉积物中甲藻孢囊分布   总被引:4,自引:0,他引:4  
2007年秋季(10月)在黄海22个站位采集表层沉积物样品进行甲藻孢囊的种类鉴定与计数,本航次中共鉴定出33种(不包括2个未确定种),优势种是锥状斯克里普藻(Scrippsiella trochoidea)、塔玛亚历山大藻(Alex-andrium tamarense)和膝沟藻属(Gonyaulaxsp.)的种类。与东海和南海甲藻孢囊的同期丰度相比,黄海的相对较低,丰度范围为10~519个/cm3,平均108个/cm3。孢囊丰度总体分布趋势从北向南递增,最高丰度区出现在长江口以北(32°19′59.88″N,122°37′5.16″E),另外,在南黄海调查海域中,中部黄海冷水团区域孢囊丰度较高,膝沟藻成为该区域的优势种,密集中心达101个/cm3。有毒甲藻孢囊在沉积物表层聚集且分布广泛,有爆发赤潮的可能。  相似文献   

11.
Several flatfishes spawn in oceanic waters and pelagic larvae are transported inshore to settle in the nursery areas, usually estuaries, where they remain during their juvenile life. Nursery areas appear as extremely important habitats, not only for juveniles but also for the earlier planktonic larval fish. Yet, the majority of nursery studies tend to focus only on one development stage, missing an integrative approach of the entire early life that fishes spent within a nursery ground. Thus, the present study assessed the influence of environmental parameters on the dynamics of the larval and juvenile flatfishes, throughout their nursery life in the Lima Estuary. Between April 2002 and April 2004, fortnightly subsurface ichthyoplankton samples were collected and juveniles were collected from October 2003 until September 2005. Larval assemblages comprised nine flatfish species, while only six were observed among the juvenile assemblages. Solea senegalensis and Platichthys flesus were the most abundant species of both fractions of the Lima Estuary flatfishes. Larval flatfish assemblages varied seasonally, without relevant differences between lower and middle estuary. Platichthys flesus dominated the spring samples and summer and autumn periods were characterized by an increase of overall abundance and diversity of larval flatfishes, mainly S. senegalensis, associated with temperature increase and reduced river flow. On the contrary, during the winter abundance sharply decreased, as a consequence of higher river run-off that might compromised the immigration of incompetent marine larvae. Juvenile flatfishes were more abundant in the middle and upper areas of the estuary, but the species richness was higher near the river mouth. Sediment type, distance from the river mouth, salinity, temperature and dissolved oxygen were identified as the main environmental factors structuring the juvenile flatfish assemblages. Juveniles were spatially discrete, with the most abundant species S. senegalensis and P. flesus associated with the middle and upper estuary, while the remaining species were associated with the lower estuarine areas. The larval fraction exhibited distinct dynamics from the juvenile estuarine flatfish community. Larval flatfishes showed a strong seasonal structure mainly regulated by biological features as the spawning season and also by seasonal variations of water characteristics. On the other hand, juvenile flatfishes were markedly controlled by site specific characteristics such as sediments structure, distance from the river mouth and salinity regime. The present study emphasized the idea that the environmental control varies throughout the ontogenetic development, stressing the importance of integrating all the early life of a species in flatfish nursery studies.  相似文献   

12.
为探明舟山近海海域仔稚鱼丰度的分布、出现概率及与环境因素的综合关系,进一步研究该海域渔业资源的补充机制,根据2019年3、4、7、11月在舟山近海海域开展的4个航次仔稚鱼生态调查资料,研究了舟山近海仔稚鱼的出现概率、群落结构(种类组成及优势种数量)的动态变化,探讨仔稚鱼群落的季节变化和对环境变化的响应,以及环境变化对仔稚鱼补充量的影响。结果显示:空间上,调查海区水深范围5~50 m,仔稚鱼集中分布于水深10~20m的近岸河口岛礁区;时间上的季节变化比较大,春夏季丰度高,冬季少。GLM模型结果显示:近岸河口型仔稚鱼在近岸出现的概率为0.65~0.95,在近海出现的概率为0.26~0.60;近海型仔稚鱼在近岸出现的概率为0.12~0.34,在近海出现的概率为0.32~0.54。仔稚鱼优势种春夏季各出现1种,秋冬季各出现2种,全年仔稚鱼优势种有4种。数量分布为:仔稚鱼种类数春季(19种)、夏季(16种)、秋季(10种)、冬季(5种),具有明显的季节性变化。按种类适温属性划分,调查海区仅出现暖温性和暖水性两种,其中暖温性15种(占已知适温类型种类的60%),暖水性10种(占40%);按生态类型...  相似文献   

13.
黄海中南部近岸海域春季鱼类浮游生物群落空间格局研究   总被引:6,自引:1,他引:5  
根据2015年春季在黄海中南部近岸海域进行的鱼类浮游生物大型浮游生物网水平拖网数据,采用生态多样性指数和多元统计分析等方法,研究了该海域鱼类浮游生物的种类组成和群落空间格局及其与环境因子的关系。结果表明,本次调查共采集到鱼类浮游生物35种,其中鱼卵21种,仔稚鱼23种。鱼类浮游生物隶属于8目18科34属,优势种为鳀(Engraulis japonicus)、鲬(Platycephalus indicus)、鱼衔属(Callionymus spp.)和小黄鱼(Pseudosciaena polyactis)。其中,鳀和鱼衔属主要分布于海州湾渔场海域,鲬主要分布于吕泗渔场海域,小黄鱼多分布于吕泗渔场北部海域。生态类型包括半咸水型、沿岸型和近海型种类。聚类分析表明,鱼类浮游生物群落可划分为以鱼衔属、鳀为优势种的站位组A(主要分布于海州湾海域)、以小黄鱼、黄鲫(Setipinna taty)等为优势种的站位组B(主要位于江苏沿岸海域)和以鲬为优势种的站位组C(主要位于江苏沿岸-近海海域),以站位组B的群落物种多样性指数和均匀度指数最高。各站位组的鱼类浮游生物的生态类型和适温类型组成不同,这与其所处的海域生境有关。典范对应分析(CCA)表明,影响春季黄海中南部鱼类浮游生物群落空间结构的主要环境因子为水深和表层温度。同时也受洋流、底质类型等多种因素的综合影响。研究结果初步揭示了黄海中南部近岸海域鱼类浮游生物群落的空间格局,可为今后科学制定该海域水产种质资源保护区、资源量化管理等资源养护管理措施提供科学依据与技术支撑。  相似文献   

14.
The structure of the summer larval fish assemblage off the eastern coast of Tunisia and its relation to environmental conditions was studied, from ichthyoplankton samples taken during a survey conducted between 23rd June and 9th July 2008. A total of 68 larval fish taxa were identified, 52 to species level. The taxonomic composition and abundance of the larval fish assemblage showed high spatial heterogeneity. Mesoscale hydrographic features, such as eddies, seem to play an important role in the spatial distribution of fish larvae in the area, enhancing concentration and retention. The larval fish assemblage was dominated by the small pelagic species Sardinella aurita (26.6% of the total larval fish abundance), followed by Engraulis encrasicolus (22.6%), Spicara spp. (8.6%) and Mullus barbatus (6.8%). Shannon–Weaver index (H′) ranged between 0 and 2.62. The highest values were found offshore, at 95 miles east of Sousse, over depths around 250 m. The diversity was higher in this region as a result of transport by currents and retention by eddies. It has also been shown that the eastern coast of Tunisia is a spawning ground for the tuna species Auxis rochei, Thunnus thynnus and Thunnus alalunga. Larvae of mesopelagic fishes represented 5.46% of the total abundance, with Cyclothone braueri, Ceratoscopelus maderensis and Lampanyctus crocodilus being the most important species. Canonical correspondence analysis (CCA) indicated that depth was the most important environmental factor in explaining species distribution.  相似文献   

15.
Seasonal and short-term variability of environmental parameters influence the spawning strategies of fish species. In this study, the spawning strategies and the transport of early stages of the two Cape hake species off South Africa were investigated. Distribution of eggs and larvae of Merluccius paradoxus and M. capensis was analysed in order to derive more detailed and species-specific information on spawning season, spawning location, and transport of early stages. Samples were collected during three pilot surveys between January and October 2007 and during an extensive survey in September/October 2008 in the southern Benguela upwelling system off South Africa. Eggs and larvae of M. paradoxus were found in greater numbers than those of M. capensis during all surveys. Highest abundances were found from September to October, indicating one spawning peak for M. paradoxus during late austral winter to spring. The western Agulhas Bank was identified as the primary spawning ground, and smaller spawning events occurred on the West Coast. Larvae of both species were mainly distributed in subsurface waters between 25 and 100 m. More than 50% of all larvae caught had a total length between 3 and 4 mm and size increased significantly with decreasing latitude. Merluccius capensis were found closer inshore than M. paradoxus, indicating that early stages of the two species followed separate drift routes. We assume that this distribution pattern most likely evolved from differences in spawning location and phenology. The spawning strategies of M. paradoxus and M. capensis are well adapted to a time-frame of optimal transport conditions favourable for larval survival in the highly variable environment of the southern Benguela upwelling system, but the peak spawning of the two species is separated in time and space.  相似文献   

16.
The abundance and distribution patterns of nearshore ichthyoplankton were investigated during a year of anomalously high sea temperatures off Oregon. Samples collected from 2 to 18 km offshore from April through September of 1983 showed increased occurrences and higher abundances of taxa usually found at distances offshore of 37 km in other years. The dominant species collected, comprising more than half of the total larval fish abundance, was the northern anchovy (Engraulis mordax). Larval anchovy have rarely been collected inshore in previous studies. Many of the dominant taxa normally found inshore, especially osmerids, were present in reduced numbers in 1983. Changes in the hydrographic conditions associated with onshore surface drift and reduced summer upwelling during the 1983 El Niño could explain the distributional patterns observed. The warm inshore waters apparently provided a substantial spatial and temporal expansion of the spawning habitat for E. mordax.  相似文献   

17.
There have been no previous studies of the composition of nearshore larval fish assemblages along the coast of Portugal. We aimed to describe the composition and horizontal distribution patterns of larval fish assemblages and their temporal dynamics near a rocky reef at depths shallower than 13 m (inshore) and at two miles (3.70 km) from shore (offshore), as well as along transects perpendicular to the shoreline, from the reef to 10 miles offshore (18.52 km). Samples were taken using 5 min sub-surface trawls at the rocky shore of the Arrábida Marine Park (W Portugal). A total of 1021 larvae were collected, belonging to 61 taxa inshore and to 29 taxa offshore. Along transects, 626 larvae of 52 taxa were collected. Most larvae belonged to coastal species associated with rocky reefs. Total larval abundance and diversity were higher from May to July, which is consistent with the spawning activity of adults. Diversity and total larval abundance decreased significantly with increasing distance from shore, both in the inshore/offshore comparison and in the transects, where this decrease was evident at a very small spatial scale (within the first mile from the reef). Species assemblages differed in the pattern of distribution, with most species clearly associated to the extreme nearshore. The distribution patterns obtained were independent of the spawning mode of species. Results are discussed in the light of the possible physical mechanisms that can potentially act at the Arrábida Marine Park to facilitate larvae retention and the role of larval behaviour.  相似文献   

18.
The larvae of two carangid fishes, silver trevally (Pseudocaranx dentex) and yellowtail scad (Trachurus novaezelandiae), were compared among coastal water masses and the East Australian Current (EAC). Samples followed a north to south gradient including a southern region of upwelling, generated as the EAC separated from the coast. Mean larval carangid densities were greater in the mixed layer (10-30 m) than the surface, but there was no difference between inshore and offshore stations or along latitudinal gradients. Overall, P. dentex recent larval growth over two days pre-capture was faster than T. novaezelandiae, and faster at inshore, coastal stations than in the EAC. Integrated larval growth rate (mm d−1) was usually faster at inshore stations for both species. T. novaezelandiae were enriched in both nitrogen (??15N) and carbon (??13C) stable isotopes relative to P. dentex. Larvae of both species captured within the upwelling region were enriched in ??15N and depleted in ??13C relative to other sites. Recent larval growth had a significant positive relationship with fluorescence (as a proxy of chlorophyll a biomass), and integrated larval growth rate had a significant positive relationship with fluorescence and larval isotope (??15N) composition. Recent and integrated growth of larval T. novaezelandiae and P. dentex was enhanced by EAC separation and upwelling, and also in coastal water; stimulated by food availability, and potentially through exploitation of a different trophic niche.  相似文献   

19.
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