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1.
阿根廷国家渔业发展研究所(INIDEP)在挪威单栅栏选择性虾拖网的基础上,经过两年的研制,在一顶双支架式虾拖网的囊头网中缝制了两个镀锌铁栅,向后倾斜45°左右,前栅栏杆的间距是47毫米,后栅栏杆的间距是25毫米。在两个铁栅的上部都有一个鱼类逃逸口, 相似文献
2.
我所科学调查船《实验号》于1979年11月—12月对南海中部海域(北纬12°00＇—15°05＇,东经110°51＇—118°00＇)进行海洋综合调查中,采用大型Ⅱ号浮游生物网(网目7.5目/厘米,网口直径113厘米),在水深1050—0米,垂直拖网采得大洋性深海鱼类标本200余尾,经鉴定其中有6种为我国鱼类新记录,隶属于3目5科,种的名录如下: 相似文献
3.
黄河口鱼类群落分类学多样性的研究 总被引：2，自引：2，他引：0
根据2013-2014年在黄河口水域进行的7个航次的鱼类资源底拖网调查数据,应用分类多样性指数分析了黄河口水域鱼类群落生物多样性的时空变化。黄河口鱼类主名录的平均分类差异指数△+理论平均值为75.5。2013-2014年调查中,该水域共捕获鱼类51种,隶属10目、27科、43属,以鲈形目、鲱形目和鲉形目鱼类居多。本次调查中鱼类群落分类多样性指数△和分类差异指数△*月变化范围分别为39.98~65.48和59.15~75.54,均表现为夏季月份最高,春、秋季月份次之,冬季最低。除春季月份外,其他月份鱼类平均分类差异指数△+均显著低于黄河口鱼类主名录的△+理论平均值。不同月份中平均分类差异指数△+也呈现一定的空间变化,夏、秋季月份绝大部分站位平均分类差异指数处于95%置信范围内,春、冬季月份个别站位的平均分类差异指数显著低于理论平均值,这与这些站位绝大多数种类集中在鲈形目有关。黄河口水域鱼类分类学多样性具有明显的时空变化,鱼类资源衰退,应加强该水域鱼类资源养护和多样性保护。 相似文献
4.
九龙江口鱼类多样性和营养级分析 总被引：1，自引：0，他引：1
2009年5月和11月对九龙江口进行了两个航次的拖网渔业资源调查,探讨了该河口鱼类群落结构和物种多样性特征。结果表明,两次拖网调查共鉴定鱼类35种,隶属于2纲12目22科。其中中上层鱼类3种,近底层鱼类7种,底层鱼类25种;暖水种22种,暖温种13种;河口性鱼类10种,海洋性鱼类25种;低级肉食性鱼类7种,中级肉食性鱼类28种。中华海鲇Arius sinensis、凤鲚Coilia mystus和红狼牙鰕虎鱼Odontamblyopus rubicundus是5月的优势种,中华海鲇Arius sinensis、凤鲚Coilia mystus和叫姑鱼Johnius belengerii是11月的优势种。5月和11月鱼类重量密度分别是471.53kg.km 2和143.97kg.km 2,5月和11月尾数密度分别为40811ind.km 2和3804ind.km 2。九龙江口鱼类多样性指数为1.20,均匀度指数为0.39,丰富度指数为3.11,营养级指数为3.55。与1985年同期的调查资料相比,九龙江口鱼类群落结构和物种多样性发生了很大的变化,平均营养级明显降低。九龙江口鱼类多样性下降的主要原因可能是过度捕捞、环境污染和栖息地丧失等。 相似文献
5.
本文阐述了长江口及附近海区鱼类的种类组成状况及其区系特点,为“三峡工程对河口生物及渔业资源的影响”的研究提供了基础科学资料。
中国科学院海洋研究所于1985年9月至1986年8月在长江口区开展了渔业资源的试捕调查,调查范围为东经121°10′-124°00′,北纬30°20''-32°00′,总调查面积21000平方公里,共设常规站30个,加设站7个(图1)。用150匹马力1)底层双拖网渔船(网周长140m,网目250mm,囊网网目40mm),每月调査一次,每站拖网1小时。拖网时同步观测站水深、温度和盐度。所获鱼类全部进行分类鉴定,并分种测定尾数、重量和长度。全年共获鱼类样品914534尾,重12359.67kg,经鉴定共165种。从1985年9,10月沿岸定置网鱼样品中又获另外2种,故全年共获鱼类167种。 相似文献
6.
东海冲绳海槽深海鱼类报告 总被引：1，自引：0，他引：1
冲绳海槽位于东海大陆架浅水区的外缘,是一北东一南西向延伸,在东南方向呈弧形突出的海槽。其北部水深在500-1000米间,南部最深达2000余米。1978年6,7月间我所“金星”号调查船在这一深水区及其附近进行了海洋综合考查。在进行底栖生物拖网时,获得一些深海鱼类标本。本文共报道深海鱼类14种,隶14属,12科,9目。 相似文献
7.
南海深海鱼类的初步报告 总被引：1，自引：0，他引：1
南海在我国濒临的四个海中面积最大，而其大陆架宽度则较狭窄，水深在200米以上的深海水域相当广阔。我国过去关于南海深海鱼类的研究报道极少，1962年《南海鱼类志》中曾记载过少数深海鱼类，但具有确切深度记录的仅有8种。在国外文献中，Gilbert和Hubbs(1920), Schultz(1938), Abe(1974 , 1975, 1976 )等曾报道过数种。
本文材料是1959-1960年在海南岛以东海域，水深200-1100米进行底栖生物拖网时所获得的标本。鉴定结果，共71种，分隶于37科，12目，其中34种为我国新记录，7种是我国在南海首次记录。
文内凡是我国新记录的种均有形态描述，并附有外形图,有些种作了分类上的讨论；对我国有过记录的种，只记有地理分布和标本采集记录。此外，就现有资料并参考有关深海鱼类文献，对这些种类的地理分布和深度分布也作了初步分析。由于调查范围较小，拖网次数不多，本文仅为南海鱼类区系提供了一些初步资料。丰富的南海深海鱼类区系，随着我国海洋调查事业的发展，还有待进一步深入研究。 相似文献
8.
黄河口及其邻近水域鱼类生态类群组成及其季节变化 总被引：1，自引：0，他引：1
根据2013—2014年在黄河口及邻近水域进行的7个航次的渔业资源底拖网调查数据,采用聚类分析和非度量多维标度排序等方法,研究了目前该水域生态环境条件下鱼类生态类群组成及其季节变化。研究表明,本次调查共捕获鱼类51种,隶属硬骨鱼纲10目27科43属;其中定居性鱼类30种,洄游性鱼类17种,河口性4种;暖温种30种,暖水种15种,冷温种6种。暖温种和定居种种数和平均网获量在各季节中均占绝对优势。春季鱼类27种,其中暖温种15种,定居性种类19种;夏季鱼类34种,暖温种和定居性种类分别为20和12种;秋季鱼类30种,暖温种和暖水种分别为16和14种,定居性种类18种;冬季鱼类15种,暖温种11种,暖水种2种,定居性种类12种。暖温性鱼类、洄游性鱼类平均网获量均在夏季最高。聚类分析和非度量多维标度排序分析表明,可将16种主要鱼类划分为A～D共4个种类群。A、B类群夏秋季在黄河口水域分布广泛,数量和质量上均占优势,该类群多为洄游性种类;C类群主要由定居种组成,各季节均有分布,春季和夏季分布较广,该类群已适应黄河口多变的环境;D类群主要为河口性鱼类,冬季较多。4个种类群平均网获量较高的站位主要集中在河口区。黄河口水域鱼类生态类群组成及其季节变化可能主要与水域温度变化、营养盐分布和鱼类洄游等有关。 相似文献
9.
胶州湾及其邻近水域渔业生物多样性的调查研究 总被引：12，自引：7，他引：12
根据2003年10月-2004年5月逐月采集胶州湾及其邻近水域作业的定置网和底拖网具渔获物的分析与测定，记述了该海区出现的106种渔业生物，并进行了定置网和底拖网的渔获物组成的比较，分析了种类组成特点及生物多样性的季节变化情况。结果表明，本调查区域渔获物以小型低值鱼类、经济无脊椎动物和经济幼鱼为主，渔获个体偏小。据此提出了保护近海生物多样性与合理利用近海渔业资源的一些建议。本次调查还首次记录了我国黄海沿岸罕见的蛇鳗科鱼类一长吻沙蛇鳗Ophisurusmacrorhynchus，为青岛近海的渔业生物多样性的研究增添了新的资料。 相似文献
10.
青岛近岸水域鱼类群落分类学多样性的研究 总被引：4，自引：0，他引：4
根据2004年春、秋季进行的渔业资源底拖网调查，应用分类学多样性指数分析了青岛近岸水域鱼类群落分类学多样性的时空变化。青岛近岸水域春季鱼类群落分类多样性指数△、分类差异指数△＊分别为58．63，72．83，秋季分别为56．03，73．98。春季等级多样性指数△^＋为73．58，接近于黄海鱼类主名录的理论平均值77．7，而秋季等级多样性指数△^＋为67．74。显著低于黄海鱼类主名录的理论平均值。春季，青岛近岸水域鱼类种类组成分类学范围较宽，大多数种类属于鲈形目、鼬形目、鲱形目、鲽形目和鳗鲡目，还有较少鳐形目的软骨鱼类。与春季相比，秋季大多数种类属于鲈形目、鼬形目、鲱形目、仙鱼目、鲽形目和鳗鲡目，但鲈形目平均种类数较春季多。春、秋季分类差异变异指数∧^＋都接近于黄海鱼类主名录理论平均值。等级多样性指数△^＋在春、秋季均表现出明显的地理空间变异，部分站位等级多样性指数△^＋偏低主要是其鱼类种类不同程度地集中在鲈形目、鼬形目和鲱形目造成的。 相似文献
11.
12.
山东荣成临洛北湾夏季大型底栖动物群落生态学初步研究 总被引：1，自引：0，他引：1
利用2010年7月在山东荣成临洛北湾所获得大型底栖动物定量分析资料,研究了夏季该海域海带养殖区和邻近水域大型底栖动物在物种组成、生物量、丰度、优势种以及物种多样性等方面的特征和空间差异,并采用MDS和CLUSTER分析了大型底栖动物的群落结构,以期为该地区以后的科学研究提供基础数据.结果表明,本次调查通过采泥和拖网共采集到大型底栖动物88种,其中采泥得到大型底栖动物51种,拖网采得大型底栖动物45种,各站位的物种多样性差异明显,物种数量从2种到21种.与环境因子的相关性分析显示,各站的物种数和丰度与DO存在明显的负相关.在所有大型底栖动物中,甲壳动物26种,多毛类环节动物24种,软体动物23种,棘皮动物8种,其他类群动物6种(鱼类5种,尾索动物1种).该海域的优势种为多丝独毛虫和短叶索沙蚕.将CLUSTER结果以43%的群落结构相似性来划分,组内的相似性为50%~60%.该海域大型底栖动物的平均丰度为854个/m2,平均生物量为134.73 g/m2,与研究海域附近的历史研究结果相比较,该海域的平均丰度和生物量仍处于较高的水平. 相似文献
13.
采用底拖网方法调查研究了闽东近海春季(5月)和秋季(10月)游泳动物群落组成、生物多样性、资源密度及时空分布格局等问题。调查中出现游泳动物70种(鱼类47种,甲壳类18种,头足类5种),隶属于15目40科64属,以鲈形目种类最多(25种)。鱼类是主要游泳动物群落,春季鱼类个体数和重量分别占总渔获的66.4%和72.3%,甲壳类分别占比33.4%和26.9%,头足类分别占比0.2%和0.8%;秋季,上述三个类群在总渔获中的占比分别为56.6%和60.4%、42.0%和37.8%以及1.4%和1.8%。春季优势种包括红狼牙虎鱼(Odontamblyopus rubicundus)、三疣梭子蟹(Portunus trituberculatus)、孔虎鱼(Trypauchen vagina)等10种,秋季优势种为龙头鱼(Harpadon nehereus)、三疣梭子蟹、六指马鲅(Polynemus sextarius)等7种;两个季节共有优势种包括三疣梭子蟹、日本 (Charybdis japonica)、龙头鱼、棘头梅童鱼(Collichthys lucidus)和六丝钝尾虎鱼(Amblychaeturichthys hexanema)5种。秋季的生物多样性指数和均匀度指数高于春季。春季平均资源密度为1013.7kg/km~2和10.2×10~4ind/km~2,高于秋季的平均值(899.0kg/km~2和6.6×10~4ind/km~2)。总体而言,鱼类是闽东近海主要的游泳动物类群,其资源密度从近岸向外海呈降低趋势,春季的资源密度高值出现在闽东外海中部水域,秋季高值则出现在南部的闽江口等水域;其春季的优势种种类多于秋季,存在一定程度季节性更替现象。 相似文献
14.
莱州湾鱼卵、仔稚鱼数量分布及其与环境因子相关关系研究 总被引：4，自引：0，他引：4
于2007年和2008年6月、8月,用大型浮游生物网对莱州湾鱼卵、仔稚鱼种类组成与数量分布进行了4个航次调查。结果表明,采集到11271粒鱼卵,隶属于4目、15科、22种(不包括2个未定名物种);仔稚鱼2942尾,隶属于4目、9科、12种(不包括2个未定名物种)。6月份是莱州湾大部分鱼类主要产卵期,鱼卵、仔稚鱼种类达25种,鱼卵优势种以斑(Clupanodon punctatus)和凤鲚(Coilia mystus)为主;仔稚鱼优势种以凤鲚、梭鱼(Mugil soiuy)和斑为主。8月份产卵的鱼类较少,仅采集到15种鱼卵、仔稚鱼,优势种均以凤鲚和鲈鱼(Lateolabrax japonicus)为主。鱼卵、仔稚鱼平面分布极不均匀,黄河、广利河和老弥河口附近海域数量较多,莱州湾中部海域数量较少。通过SPSS软件分析发现,鱼卵数量与仔稚鱼、表层铵盐含量呈显著正相关(r=0.438,0.604,P0.01),与盐度、透明度呈负相关(r=-0.343,-0.329,P0.05);仔稚鱼数量仅与鱼卵数量和表层铵盐含量呈显著正相关(r=0.438,0.536,P0.01),与其它环境因子没有明显相关关系(P0.05)。 相似文献
15.
Density,biomass and community structure of demersal fishes off the Pacific coast of northeastern Japan 总被引：8，自引：0，他引：8
Demersal fish communities were studied on the lower continental shelf and the upper continental slope along the Pacific coast of northeastern Japan. Species composition, number and weight of each species were examined based on otter trawl samples at 45 stations. Mean density and biomass of demersal fishes were 131 ha–1 and 21 kg ha–1, respectively. The ten most abundant species comprised of about 95% of total number and weight of overall catch indicating simple species composition. Gadiform fishesTheragra chalcogramma, Gadus macrocephalus andPhysiculus maximowiczi were the most important species by number, weight and frequency of occurrences, and three main community types represented by the three key species were recognized.Theragra-dominant community showed higher density and biomass, and lower diversity thanPhysiculus-dominant community did. Species diversity of demersal fish community was negatively correlated to density and biomass. Density and biomass of demersal fish community were high on the uppermost slope, and the high abundance resulted from low-diversity communities dominated byT. chalcogramma andG. macrocephalus. 相似文献
16.
Fish utilization of a salt marsh intertidal creek in the Yangtze River estuary, China 总被引：6，自引：0，他引：6
Binsong Jin Cuizhang Fu Junsheng Zhong Bo Li Jiakuan Chen Jihua Wu 《Estuarine, Coastal and Shelf Science》2007,73(3-4):844-852
The structure and temporal variations of the fish community in salt marshes of Chinese estuaries are poorly understood. Fish utilization of a salt marsh intertidal creek in the Yangtze River estuary was studied based on quarterly sampling surveys in July and November, 2004, and February and May, 2005. Fishes were collected by consecutive day and night samplings using fyke nets during the ebbing spring tides. A total of 25,010 individuals were caught during the study. 17 families and 33 species were documented, and the most species-rich family was Gobiidae. Three species, Synechogobius ommaturus, Chelon haematocheilus and Lateolabrax maculatus together comprised 95.65% of the total catch, which were also the most important commercial fishery species in the Yangtze River estuary. The fish community was dominated by juvenile individuals of estuarine resident species. Time of year significantly affected fish use of salt marshes, but no significant effects of diel periodicity on the fish community were found except for fish sampling in July. These findings indicate that salt marshes in the Yangtze River estuary may play important nursery roles for fish community. 相似文献
17.
《African Journal of Marine Science》2013,35(1):663-674
Between 1978 and 1990,1 800 copper sharks Carcharhinus brachyurus were caught in the shark nets that protect the swimming beaches of Natal. The species constituted 9,6 per cent of the total shark catch. Annual catches and catch rates fluctuated widely about a mean of 138 sharks and 3,5 sharks·km net?1 respectively. Most sharks were caught at the southern beaches during the annual Natal sardine run in June and July, when shoals of pilchard Sardinops ocellatus move into the waters off southern Natal. Catches were dominated by sharks >140 cm pre-caudal length PCL. Mature males (generally ≥ 175 cm PCL) were present for much of the year, but mature females (generally ≥ 190 cm) and immature sharks were only abundant in June and July. Gonad indices in males were highest in March and April, whereas high gonad indices and large ova were recorded in females in June and July. Mating appears to take place after July and parturition about 12 months later, both occur south of the netted region. The smallest of 50 pregnant females caught was 178 cm. Mean embryo length within a litter ranged from 17 to 54 cm. Teleosts were found in 92 per cent and pilchard in 84 per cent of stomachs containing food. 相似文献
18.
《African Journal of Marine Science》2013,35(3):465-472
The feasibility of a directed trap-fishery for panga Pterogymnus laniarius was investigated with special emphasis on minimising the bycatch. A total of 1 302 fish, representing 19 species, was captured in 59 trap deployments at three locations along the Eastern Cape coast of South Africa between September 2002 and July 2004. Panga comprised over 55% of the total catch, with an average of 12 panga per trap haul. Depth and substrate type had a significant effect on the species composition of the catch. Panga comprised 77% of the catch in depths >50m, whereas other commercially important species contributed 11% to the total catch in water >50m. No kingklip Genypterus capensis were captured in the traps and shallow-water Cape hake Merluccius capensis accounted for only 0.2% of the total catch composition. The findings suggest that trap-fishing provides a new fishing opportunity in South Africa with a high catch per unit effort for the target species and a low level of bycatch. 相似文献
19.
Standing stocks and production rates of phytoplankton and planktonic copepods in the Inland Sea of Japan 总被引：1，自引：0，他引：1
Standing stocks and production rates of phytoplankton and planktonic copepods were investigated at 15 stations in the Inland Sea of Japan during four cruises in October–November 1979, January, April and June 1980. The overall mean of phytoplankton biomass was relatively constant during the study period, ranging from 2.3 mg chl.a m–3 in April to 3.6 mg chl.a m–3 in October–November. Primary production was low in January (mean: 90 mg C m–2 d–1), but higher than 375 mg C m–2 d–1 on the other occasions. Integrated annual primary production was 122 g C m–2 yr–1. In terms of carbon weight,Paracalanus parvus was the most important copepod species. The variation of the mean copepod biomass (range: 7.6 mg C m–3 in April to 20.2 mg C m–3 in June) was smaller than that of copepod production, which was estimated by the Ikeda-Motoda's physiological method. Copepod producion was low in cold seasons (0.6 and 0.9 mg C m–3 d–1 in January and April, respectively), and increased, following the elevation of primary production, to 4.9 mg C m–3 d–1 in June. Annual copepod production was 33.7 g C m–2 yr–1, of which herbivore (secondary) production was 26.4 g C m–2 yr–1 (21.7% of primary production). The ratios of pelagic planktivorous fish catch and total fish catch to the primary production were 0.82 and 1.8%, respectively, indicating very high efficiency in exploiting fishery resources in the Inland Sea of Japan. 相似文献
20.
《African Journal of Marine Science》2013,35(4):479-496
The primary purpose of this study was to evaluate the effectiveness of current management of the KwaZulu-Natal (KZN) shore-based marine linefishery. Methods used included a stratified-random creel survey and an associated questionnaire survey. The study was undertaken between February 2009 and January 2010. Total participation ranged between 41 283 and 68 087 shore-anglers. Results show that there has been little change in participation in the KZN shore-fishery since 1994–1996. In contrast, total angler effort (779 382–843 702 angler-days y?1) has decreased substantially over the past 13 years. Overall catch per unit effort (CPUE) for the KZN shore-linefishery amounted to 0.18 ± 0.3 fish angler?1 h?1 or 0.07 ± 0.13 kg angler?1 h?1. In all, 84 fish species, belonging to 39 families, were recorded in catches of shore-anglers during the study period. Only five species accounted for 75% of the catch recorded along the coast (Sarpa salpa 34.8%, Pomatomus saltatrix 14.7%, Diplodus capensis 14.5%, Pomadasys olivaceum 6.5% and Rhabdosargus holubi 4.9%). The total annual catch for the KZN shore-linefishery was estimated between 249.2 and 276.7 t y?1 (or 636 589–706 995 fish y?1). Analysis of overall CPUE, catch composition and total catch in the shore-based linefishery of KZN suggested that it is currently in a relatively stable condition and that little change has occurred over the past 13 years. However, comparisons of species-specific CPUE values from this study with recent literature suggest that some species (e.g. Argyrosomus japonicus) are severely overexploited. Over the past few decades there seems to have been a gradual transition in landings from long-lived, high trophic-level, piscivorous fish (e.g. A. japonicus) to more short-lived, low trophic-level species (e.g. S. salpa). The results therefore suggest that present exploitation levels may not be sustainable for certain slow-growing, long-lived fish species. Current management regulations appear to have limited effectiveness based on poor angler compliance and knowledge of the regulations. In this regard, it is important to consider alternate management measures that may offer more effective protection to fish and at the same time be more easily understood by all anglers in the linefishery. Recommendations for improved management and the importance of the establishment of an effective MPA network are briefly discussed. 相似文献