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1.
长江口斑尾刺虾虎鱼与纹缟虾虎鱼肌肉营养成分比较   总被引:1,自引:0,他引:1  
章龙珍  宋超  庄平  赵峰  闫文罡 《海洋渔业》2011,33(3):304-309
采用生化分析的方法,对长江口斑尾刺虾虎鱼(Acanthogobius ommaturus)和纹缟虾虎鱼(Tridentiger trigonocephalus)的肌肉营养成分进行了分析,并对两者的营养品质进行了比较.结果表明:斑尾刺虾虎鱼的水分含量显著高于纹缟虾虎鱼(P<0.05),而粗蛋白、粗脂肪和粗灰分含量显著低于...  相似文献   

2.
宋业晖  薛莹  徐宾铎  张崇良  任一平 《水产学报》2020,44(12):2017-2027
根据2011及2013年在海州湾及其邻近海域进行的渔业资源底拖网调查资料和胃含物分析数据,应用多元统计分析法和生态位重叠指数法等,研究了海州湾皮氏叫姑鱼、小黄鱼和棘头梅童鱼3种石首鱼的食物组成及其营养—空间二维生态位的重叠情况。结果显示,皮氏叫姑鱼属于底栖动物食性,主要摄食虾类、端足类和多毛类;小黄鱼属于底栖动物和游泳动物食性,主要摄食鱼类、虾类、头足类和磷虾;棘头梅童鱼属于底栖动物食性,主要摄食虾类、毛虾类、磷虾和糠虾。这3种石首鱼的营养生态位宽度较为接近,其中小黄鱼的营养生态位宽度(2.69)和空间生态位宽度(2.78)均最高,皮氏叫姑鱼的营养生态位宽度(2.59)最低,而棘头梅童鱼的空间生态位宽度(2.42)最低。3种石首鱼的营养生态位重叠指数为0.24~0.46,其中皮氏叫姑鱼与棘头梅童鱼的营养生态位重叠最高。它们的空间生态位重叠指数为0.19~0.30,表明这3种鱼在空间方面存在一定的分隔。它们的营养—空间二维生态位重叠指数为0.05~0.11,其中皮氏叫姑鱼与棘头梅童鱼的重叠指数最高,因此有可能发生激烈的食物竞争,而小黄鱼与皮氏叫姑鱼和棘头梅童鱼之间则可以通过营养和空间生态位的分化来降低种间竞争。  相似文献   

3.
黄河口水域主要鱼种的时空生态位宽度和重叠   总被引:3,自引:2,他引:1       下载免费PDF全文
生态位在研究群落结构、种间关系和生物多样性等方面具有重要作用。为深入了解黄河口水域鱼类群落结构和种间关系,本研究根据2013—2014年在黄河口水域进行的7个航次的渔业资源底拖网调查数据,应用平均拥挤度、生态位宽度和生态位重叠值等指数研究了该水域12种鱼类的时空生态位宽度和重叠特征。结果表明,黄河口水域主要鱼种时间生态位宽度变化范围为0~1.53,其中矛尾虾虎鱼(Chaemrichthys stigmatias)和方氏云鳚(Enedrias fangi)时间生态位宽度值较高,安氏新银鱼(Neosalanx anderssoni)和鮻(Liza haematocheila)较低。主要鱼种空间生态位宽度具有明显季节变化。所有鱼种间的平均空间生态位重叠值也有着明显的季节差异。生态位宽度和重叠值与各鱼种数量、分布、生态习性和生境状况密切相关,反映了该海域不同鱼种对生境资源的不同利用能力。  相似文献   

4.
根据2018年4月(春季)、10月(秋季)在舟山群岛东侧海域进行的渔业资源调查数据, 利用相对重要性指数确定调查海域各种鱼类的重要性程度, 应用平均拥挤度、Shannon指数及Pianka指数, 分析了该海域主要鱼类的生态位宽度及生态位重叠。结果表明, 春季与秋季主要鱼类分别有10种与12种。春、秋两季主要鱼类生态位宽度值范围分别为0.06~2.01、0.34~2.19, 两季生态位宽度值差异较大, 其中广生态位种(Bi≥2.0)春季仅小黄鱼(Larimichthys polyactis) 1种, 而秋季为叫姑鱼(Johnius grypotus)、鮸(Miichthys miiuy)、小黄鱼和六丝钝尾虾虎鱼(Amblychaeturichthys hexanema) 4种, 春、秋两季中生态位种(2.0>Bi≥1.0)均为6种, 窄生态位种(1.0>Bi>0)春季3种, 秋季为2种。两季生态位重叠程度差异较大, 春季生态位重叠显著的种对有20对, 占总种对数的44.44%, 重叠程度相对较高; 而秋季主要鱼类重叠程度较低, 种对间重叠显著的只有16对, 占总种对数的24.24%。冗余分析(RDA)显示温度、盐度变化是影响春秋季主要鱼类生态位分化的直接因素, 水深则为重要因素, 主要鱼类受这些环境因子的影响表现出较为明显的生态位分化现象。  相似文献   

5.
2种虾虎鱼细胞色素b基因全序列克隆与分析   总被引:1,自引:0,他引:1  
测定了矛尾刺虾虎鱼(Acanthogobius hasta)和红狼牙虾虎鱼(Odontamblyopus rubicundus)的线粒体细胞色素b(Cytb)基因全序列。2种虾虎鱼Cytb基因序列全长均为1141bp,通过序列比对,检测到266个变异位点,序列中碱基转换频率高于颠换,碱基替换主要发生在密码子第3位。结合GenBank中的虾虎鱼科其他物种的细胞色素b基因全序列,利用Kimura-双参数模型分析遗传距离表明,10种虾虎鱼科鱼类的遗传差异在0.118~0.330之间,大头新虾虎鱼(Neogobius kessleri)与同属的裸喉新虾虎鱼(N.gymnotrachelus)遗传距离最小,为0.118;大头新虾虎鱼和矛尾刺虾虎鱼遗传距离最大,为0.330。以Cytb基因全序列构建的NJ进化树分析表明,10种虾虎鱼分为3个主要类群,红狼牙虾虎鱼和矛尾刺虾虎鱼聚为1支,且与其余8种虾虎鱼类遗传距离较远。  相似文献   

6.
为了解长江口盐沼湿地优势鱼类群落结构及其种间关系,采用插网调查,利用2019年5—10月的调查数据,基于生态位宽度和生态位重叠度指数对长江口崇明东滩(31°27''N,121°56''E)和九段沙盐沼湿地(31°10''N,121°57''E)鱼类群落的优势种生态位进行研究。研究结果表明,春、夏、秋3个季节共采获10个优势种,其中鮻(Liza haematocheila)、花鲈(Lateolabrax maculatus)和拉氏狼牙虾虎鱼(Odontamblyopus rubicundus)在3个季节中均为优势种。在10个优势种中,时间生态位宽度值变化范围为0.11~1.70,其中拉氏狼牙虾虎鱼时间生态位宽度值最大,小黄鱼(Larimichthys polyactis)值最小;空间生态位宽度值变化范围为0.57~1.53,其中棱鮻(Liza carinatus)空间生态位宽度值最大,小黄鱼值最小。长江口盐沼湿地鱼类优势种生态位宽度呈现显著的季节性变化趋势。长江口盐沼湿地鱼类优势种的时空生态位重叠值较高,其中具重叠意义的鱼种对(species pairs)高达73.33%,具有显著重叠意义的鱼种对高达48.89%。结论认为,长江口盐沼湿地鱼类优势种的时空分布具有相似性,存在明显的竞争关系。  相似文献   

7.
胶州湾鱼类群落优势种组成的时空变化   总被引:5,自引:2,他引:3       下载免费PDF全文
优势种对群落结构有明显的控制作用,但优势度作为一个综合指标在不同时空尺度下的变异性常常被忽略。根据2008―2012年在胶州湾进行的渔业资源调查数据,以相对重要性指数(index of relative importance,IRI)表征鱼类种类优势度,应用bootstrap和多元线性回归模型(the multiple linear regression model)等方法分析了该海域的优势种组成及其在年份、季节、海区间的变化。结果表明,优势种有明显更替,六丝钝尾虾虎鱼(Chaeturichthys hexanema)和方氏云鳚(Pholis fangi)等小型底层鱼类更替为主要优势种,2008―2012年间分别占总渔获量的9.79%和10.71%,优势度分别为3285和2068;优势种存在明显季节变化,春季为方氏云鳚,夏季为细条天竺鲷(Apogonichthys lineatus),秋季和冬季是六丝钝尾虾虎鱼;空间上,湾口和湾内优势种组成相似,与湾外差异较大。多元线性回归分析表明,主要优势种中方氏云鳚优势度逐年升高,而六丝钝尾虾虎鱼相对下降,年际差异极显著(P0.01),呈现明显的群落演替过程。优势度主要受洄游产卵、水温、底质类型、水深以及饵料生物等因素的综合影响。  相似文献   

8.
为探究太湖鱼类的营养生态位特征,于2019~2020年开展了太湖鱼类的碳氮稳定同位素调查,分析了鱼类营养生态位大小、生态位重叠度及营养级。研究结果表明,鱼类δ13C值范围为-27.67‰~-17.92‰,δ15N值范围为6.02‰~20.31‰。营养生态位大小(SEAc值)范围为0.14‰2~20.43‰2,其中黄颡鱼的生态位最大,光泽黄颡鱼的生态位最小。短颌鲚、陈氏短吻银鱼和鲢的SEAc值均较小,表明他们利用的食物源和生境范围较窄,鳙的SEAc值较大,表明其利用的食物源和生境范围较广。鱼类的营养生态位重叠度为0~70.6%。大银鱼与翘嘴鲌的生态位重叠度最大(70.6%),其次为鲈与翘嘴鲌(39.9%),其余物种间的生态位重叠度范围为0~38.9%。短颌鲚与其他肉食性鱼类的生态位重叠度较小,表明他们之间的食物资源竞争较弱。陈氏短吻银鱼与鲢、鳙在生态位上存在明显的分离,这与陈氏短吻银鱼专食浮游动物有关。鱼类营养级范围为0.73~3.62,鮠一种的营养级最高,泥鳅的营养级最低。分析表明,鱼类营养生态位的大小与其摄食的食物种类以及对不同生境的利用程度有关;大部分鱼类间生态位重叠度较低,表明鱼类在资源利用上存在较大分离。本研究结果也为太湖鱼类食物网分析及渔业资源管理提供了基础数据。  相似文献   

9.
基于16S rRNA基因部分序列的长江口虾虎鱼科鱼类系统分类   总被引:1,自引:0,他引:1  
为了确定线粒体16S rRNA基因在长江口虾虎鱼科鱼类系统分类及物种鉴定中的作用,采用16S rRNA基因特异扩增测序及Gen Bank已有序列联合配对分析的方法,对长江口虾虎鱼科9属11种鱼类34个16S rRNA基因片段的序列进行比较和系统分类研究。统计分析显示,虾虎鱼科鱼类该片段的A含量明显高于其它3个碱基含量,A+T的平均含量高于G+C的平均含量,第3密码子位点G+C含量最高,其平均值为51.1%,变化范围为49.8%~53.2%。全部转换位点多于颠换位点,转换/颠换比值为1.45。依据Maximum Composite Likelihood模型,得出11种虾虎鱼科鱼类种间遗传距离平均值为0.151,种内为0.002,种间遗传距离是种内遗传距离的76倍。通过邻接法(Neighbor-joining,NJ)构建系统发育树,显示长江口虾虎鱼科鱼类为明显的单系群,并进一步佐证把传统形态分类中弹涂鱼科的青弹涂鱼(Scartelaos histiophorus)和大弹涂鱼(Boleophthalmus pectinirostris)及鳗虾虎鱼科的拉氏狼牙虾虎鱼(Odontamblyopus lacepedii)和红狼牙虾虎鱼(Odontamblyopus rubicundus)归属于虾虎鱼科的合理性。聚类结果显示红狼牙虾虎鱼和拉氏狼牙虾虎鱼聚在一起,其节点支持率达100%,两者可能为同种异名。本研究表明,线粒体16S rRNA基因序列作为分子标记对虾虎鱼科鱼类进行物种鉴定和系统分类是可行的,可为虾虎鱼类的亲缘关系分析提供基础资料。  相似文献   

10.
温州瓯飞滩邻近海域主要游泳动物群落结构   总被引:1,自引:1,他引:0       下载免费PDF全文
基于2013年春季(5月)在温州瓯飞滩邻近海域进行的渔业资源调查数据,通过种间相遇机率(PIE)、方差比率法(VR)、卡方检验(χ~2)、联结系数(AC)、共同出现百分率(PC)、点相关系数(Φ)、Ochiai指数、功能群划分和营养级构成等方法,对主要游泳动物群落物种间的相互关系进行综合分析。结果表明:总体种间相遇机率为0.65,六丝钝尾虾虎鱼(Amblychaeturichthys hexanema)与其他种相遇机率最高(0.244),而凤鲚(Coilia mystus)最低(0.001)。种对为六丝钝尾虾虎鱼和细螯虾(Leptochela gracilis)相遇机率最大(0.305),凤鲚与中华小沙丁鱼(Sardinella nymphaea)相遇机率最小(0.003)。主要游泳动物物种间总体上呈显著正相关,绝大多数种对表现为弱联结性或无联结性,说明主要种群具有相对独立分布的特性。按食性类型可把主要游泳动物划分成5个功能群,主导功能群为杂食者,植食者功能群无物种分布。主要游泳动物占据第二、三、四级营养级。该海域生态系统结构比较成熟,整体群落结构稳定,但主要游泳动物数量及种类资源现状不乐观。  相似文献   

11.
Niche differentiation facilitates the coexistence of species within a community through avoidance of competition via mechanisms involving spatial, temporal and/or trophic dimensions. Where invasive species coexist in their non‐native range, niche differentiation could allow their persistence at higher levels of abundance. Here, we tested whether there was temporal and/or trophic niche differentiation between two congeneric invasive goby species (Rhinogobius cliffordpopei and Rhinogobius giurinus) in the sublittoral habitat of Lake Erhai (south‐west China) through quantifying their diel and seasonal rhythm of locomotion activities, feeding activities and diet composition. Both species displayed two similar diel peaks in activity and two main feeding periods (6:00–10:00 and 18:00–22:00), with rhythms of locomotion and feeding activity not differing significantly between the species in each season. Their diets had a high degree of overlap, being primarily composed of macrozooplankton, aquatic insects and shrimp larvae, with no diel changes across the seasons. Thus, in this habitat, there was no clear temporal or trophic niche differentiation between the invasive congeners, indicating their coexistence with high temporal and trophic overlap. In conjunction with data from the littoral and profundal habitats, the gobies revealed different strategies across the habitats (e.g. spatial segregation, trophic niche differentiation) that minimised their competitive interactions and promoted their coexistence. This suggests that the interactions of invasive fishes during the integration into native communities can be context dependent, varying according to factors including habitat and the availability of food resources.  相似文献   

12.
Generalist feeding strategies are favoured in stressful or variable environments where flexibility in ecological traits is beneficial. Species that feed across multiple habitat types and trophic levels may impart stability on food webs through the use of readily available, alternative energy pools. In lakes, generalist fish species may take advantage of spatially and temporally variable prey by consuming both benthic and pelagic prey to meet their energy demands. Using stomach content and stable isotope analyses, we examined the feeding habits of fish species in Alaska's Arctic Coastal Plain (ACP) lakes to determine the prevalence of generalist feeding strategies as a mechanism for persistence in extreme environments (e.g. low productivity, extreme cold and short growing season). Generalist and flexible feeding strategies were evident in five common fish species. Fish fed on benthic and pelagic (or nektonic) prey and across trophic levels. Three species were clearly omnivorous, feeding on fish and their shared invertebrate prey. Dietary differences based on stomach content analysis often exceeded 70%, and overlap in dietary niches based on shared isotopic space varied from zero to 40%. Metrics of community‐wide trophic structure varied with the number and identity of species involved and on the dietary overlap and niche size of individual fishes. Accumulation of energy from shared carbon sources by Arctic fishes creates redundancy in food webs, increasing likely resistance to perturbations or stochastic events. Therefore, the generalist and omnivorous feeding strategies employed by ACP fish may maintain energy flow and food web stability in extreme environments.  相似文献   

13.
李凡  丛旭日  张孝民 《水产学报》2021,45(8):1384-1394
根据2010—2019年夏季莱州湾底拖网调查数据,研究了4种大型甲壳类(中国明对虾、三疣梭子蟹、日本蟳和口虾蛄)的优势度、种间联结、空间生态位特征,并应用碳氮稳定同位素数据分析了4种大型甲壳类的营养级、营养生态位与摄食来源。结果显示,口虾蛄、日本蟳是目前莱州湾夏季甲壳类最主要的优势种,放流种类中国明对虾、三疣梭子蟹为群落的重要种;4种大型甲壳类的种间联结性不强,显著正联结主要出现于中国明对虾与其他三者之间;日本蟳空间生态位宽度最高(2.45),口虾蛄(2.13)次之,中国明对虾(1.92)和三疣梭子蟹(1.93)较低;生态位重叠较高主要发生于中国明对虾与其他3种之间;4种大型甲壳类营养级相近(3.02~3.28),中国明对虾生态位总面积最大,三疣梭子蟹与日本蟳、口虾蛄的生态位总面积相近,三疣梭子蟹和日本蟳的营养生态位重叠较高;摄食来源分析表明,中国明对虾摄食双壳类比例更高,其他3种摄食来源同质化程度较高。目前莱州湾三疣梭子蟹和中国明对虾的优势度低于口虾蛄和日本蟳,表明增殖放流虽然扩大了三疣梭子蟹和中国明对虾的种群规模,但尚未较大程度改变甲壳类群落结构。综合4种甲壳类的群落地位、种间联结性、空间生态位宽度与重叠、营养级与营养生态位以及摄食来源的研究结果,中国明对虾与其他三者竞争相对较小,而三疣梭子蟹与日本蟳、口虾蛄竞争较大。为最大程度发挥增殖效益,建议在确定放流地点和放流数量时,应着重考虑相近生态位物种对放流物种的竞争和限制。  相似文献   

14.
We analysed the stomach contents of fish species inhabiting fresh and brackish waters of South Korea to improve our understanding of feeding preferences and competition among them. The stomach contents of 54 fish species contained 237 genera, 187 families, 84 orders, 37 classes and 25 phyla. Faunal food items included 164 genera, 129 families, 47 orders, 23 classes and 16 phyla. Floral food items were relatively limited, comprising 73 genera, 58 families, 37 orders, 14 classes and nine phyla. The most consumed faunal food item was Chironomidae (Diptera), whereas the most consumed floral food item was Fragilariaceae (Fragilariales). The 54 fish species were classified into six groups using hierarchical and nonmetric multidimensional analysis based on their food preferences: Group 1 (G1) fishes were zooplanktivores; group 2 (G2) fishes mainly consumed Malacostraca, Maxillopoda and other fishes (e.g. Osmeriformes); groups 3 (G3) and 4 (G4) consumed Chlorophyta, Cyanobacteria and Bacillariophyta; and groups 5 (G5) and 6 (G6) consumed macroinvertebrates. Network analysis was used to link fishes with their food items. The highest hub score for food items was for macroinvertebrates, including Diptera (13.9), Ephemeroptera (11.1) and Trichoptera (8.2). Niche breadth analysis represented the diversity of food items among the feeding groups (G1–G6). Food item diversity was high for planktivores (G1 and G3) and omnivores (G4). Conversely, the dietary diversity of carnivores (G2) and insectivores (G5) was limited. Competitive relationships between fishes, as represented by the niche overlap in G5 (insectivores), were higher than those between other groups.  相似文献   

15.
基于2016年10月和2017年4月在台州益顽湾海域(27.9°N~28.6°N和121.1°E~121.9°E)的渔获物调查数据,采用功能群结合种间相遇机率(PIE)与生态位的方法,对主要游泳动物群落特征进行研究。结果显示:春季与秋季主要游泳动物分别有13种与11种,多以短距离洄游种或定居种为主,季节更替率较低;底栖动物/游泳动物食性功能群(FG4)在两季主要游泳动物中占优势地位且营养级偏低;春季与秋季主要游泳动物种间相遇机率总和分别为0.66与0.76,秋季较春季的种间相遇机率高;春秋两季的生态位宽度差异均较大,春季广生态位种4种,中生态位种7种,秋季广生态位种5种,中生态位种4种,窄生态位种两季均为2种;生态位宽度(Bi)与种间相遇机率(PIE)呈显著正相关;三疣梭子蟹(Portunus trituberculatus)在两季相遇机率值最高且生态位宽度值最大,其竞争能力和利用资源的能力最强;春季与秋季种对间生态位重叠值分别为0.14~0.88与0.21~0.91,表明两季种对间重叠程度不均匀。综上,该海域主要游泳动物组成的季节性变化较小,单一功能群占主导且多为中低营养级物种,其生态位宽度值与种间相遇机率值却较大,可能造成了群落数量波动、群落结构与功能稳定性下降。  相似文献   

16.
Tributaries of the Colorado River Basin, historically home to a complex of endemic omnivores collectively referred to as the ‘three species’; flannelmouth sucker (Catostomus latipinnis), bluehead sucker (C. discobolus) and roundtail chub (Gila robusta), have experienced the establishment of numerous non‐native fish species. In this study, we examine the impacts of the trophic ecology of non‐native fishes on the ‘three species’ in the San Rafael River, Utah, USA. We employ a suite of abundance comparisons, stable isotope techniques and size‐at‐age back‐calculation analyses to compare food web structure and growth rates of the ‘three species’ in study areas with and without established populations of non‐native species. We found that the ‘three species’ are more abundant in areas with few non‐native fishes present, regardless of habitat complexity. Stable isotope analyses indicate non‐native fishes lengthen the food chain by 0.5 trophic positions. Further, the trophic niche spaces of the native fishes shift and are narrower in the presence of non‐native fishes, as several non‐native species’ trophic niche spaces overlap almost entirely with each of the ‘three species’ (bluehead sucker and flannelmouth sucker 100%, roundtail chub 98.5%) indicating strong potential for competition. However, the ‘three species’ demonstrated no evidence of reduced growth in the presence of these non‐native fishes. Collectively, these results suggest that while non‐native fishes alter the food web structure presenting novel sources of predation and competition, mechanisms other than competition are controlling the size‐structure of ‘three species’ populations in the San Rafael River.  相似文献   

17.
Temporary water bodies are temporally variable ecosystems supported primarily by rainwater. The biota supported by such water bodies present a range of capacities to remain in this environment for all or part of their life cycles. During floods, temporary pools can connect with permanent streams, promoting changes in trophic networks in the aquatic food webs. The aim of this research was to analyse the feeding ecology of a fish community in a temporary pool near of Tlacotalpan, in the Mexican southeast, in order to understand the dynamics of the feeding habits. First, we identified feeding habits that can be interpreted as guilds of the fishes in the temporary pool: the annual killifish Millerichthys robustus (the only autochthonous species) is planktophagous; Cynodonichthys tenuis and Astyanax aeneus are insectivores; Dormitator maculatus and larvae of amphibians (Lithobates sp.) are mainly detritivorous; and Poecilia mexicana is planktophagous and insectivorous. We then estimated the effect of coexistence on niche breadth and overlap. The niches of M. robustus and P. mexicana evidenced overlap, but the breadth was adjusted inversely, suggesting feeding specialisation in M. robustus in response to competition. We documented the existence of two cohorts of M. robustus; the niche breadth of the first and second cohorts suggesting different strategies probably related to competition under variable conditions. The niche of C. tenuis and A. aeneus, and D. maculatus and tadpoles overlapped, following a pattern of feeding generalisation in response to competition.  相似文献   

18.
Floodplain lakes are ecosystems characterised by annual flood and dry cycles. Fish ecology is influenced by the flood pulse due to the large influx of allochthonous food resources and diversification of habitats during the flood cycle, while during the dry cycle, fishes tend to be confined in reduced habitat. The aim of this study was to evaluate the seasonal variation in trophic niche width and overlap of four species—Mylossoma duriventre, Prochilodus nigricans, Cichla.pleiozona and Serrasalmus rhombeus—in an Amazonian floodplain lake. Stable isotope analyses were used to estimate trophic niche width and overlap during the flood and dry seasons. We hypothesised broader niche width for all species during the flood cycle and a higher degree of overlap between the two piscivorous fishes during the dry cycle. Isotopic niche width was 72% broader for P. nigricans, 61% for S. rhombeus and 54% for C. pleiozona during the dry cycle, which did not support our hypothesis. Core niche width overlaps were not observed between piscivorous species in either flood or dry cycle. The results indicate that seasonal variation in isotopic niche width is specific to feeding habit. Understanding how fish trophic ecology responds to changes in the hydrological regime during the seasons is crucial for sustainable fishery management in a region where many people rely heavily on fish for nutritional and economic purposes.  相似文献   

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