莱州湾芙蓉岛人工鱼礁区生态系统能量流动及仿刺参生态容量评估

基于2019年莱州湾芙蓉岛人工鱼礁区渔业资源调查数据,利用Ecopath with Ecosim 6.6 (EwE 6.6)软件构建了芙蓉岛人工鱼礁区生态系统Ecopath模型,系统分析了芙蓉岛人工鱼礁区生态系统的能量流动规律和结构特征,估算了仿刺参(Apostichopus japonicus)的生态容量。Ecopath模型由16个功能组组成,基本涵盖了芙蓉岛人工鱼礁区生态系统能量流动的主要过程。结果发现,生态系统各功能组的营养级范围为1.000~3.978,其中,花鲈(Lateolabrax maculatus)处于最高营养级;生态系统总转换效率为10.6%,来自初级生产者的转换效率为10.8%,来自碎屑的转换效率为10.1%;生态系统总流量为2 596.108 t/(km2·a),其中44%来自碎屑;系统总初级生产量/总呼吸量为1.454,连接指数为0.402,系统杂食指数为0.211,Finn´s循环指数和平均路径长度分别为8.860%和2.980。结果表明,芙蓉岛人工鱼礁区生态系统成熟度和稳定性较低,食物网结构较简单。根据模型计算得出,仿刺参的生态容量为131 t/km2,是现存量的6.55倍,具有较大的增殖潜力。     

南海北部陆坡海域生态系统营养结构和能量流动分析

陆坡是陆架到深海的过渡区域,具有独特的地理生态环境特征,能量和物质交换活跃。为了解南海北部陆坡海域生态系统状况,实验根据2015—2016年南海北部陆坡海域渔业资源和海洋生态调查数据,利用Ecopath with Ecosim 6.5(EwE6.5)软件构建了由22个功能组组成的南海北部陆坡海域生态通道模型,分析了该海域生态系统营养结构、能量流动及生态系统总特征。结果显示,南海北部陆坡生态系统各功能组营养级范围为1.00～4.47,海豚占据了最高的生态位。关键度指数(KSI)分析表明,中型浮游动物、鸢乌贼为南海陆坡生态系统的关键种。生态系统中能量流动主要以碎屑食物链为主,能量来源于碎屑的比例为52%。生态网络分析表明,系统能量主要分布在6个整合营养级,来源于初级生产者和碎屑的转化效率分别为21.26%和22.39%,系统平均转化效率21.94%。研究表明,南海陆坡海域生态系统具有较高的生态转化效率。     

基于Ecopath模型的大亚湾黑鲷生态容量评估

为评估大亚湾黑鲷(Sparusmacrocephalus)的生态容量,根据2015年渔业资源和生态环境调查数据,利用Ecopathwith Ecosim6.5(EwE)软件构建了由26个功能组组成的大亚湾Ecopath模型,分析了大亚湾生态系统的基本特征,并结合食物网结构和能量流动估算了黑鲷的增殖生态容量。结果显示,黑鲷营养级为3.44,营养转化效率为0.302;大亚湾生态系统各功能组的营养级在1～3.95之间,系统总转化效率为7.636%,总初级生产量/总呼吸量为2.142,系统连接指数为0.364,系统杂食性指数为0.210,表明系统各营养级转化效率较低,能量未被充分利用;系统总转化效率低于10%,营养级I、II流向碎屑量占总流向碎屑量的98.11%,说明能量传递发生阻塞,具有增殖空间。经估算黑鲷生态容量为0.034 t/km2,是现存生物量的1.4倍,此时其他浮游生物食性鱼类的转化效率等于1,系统处于平衡状态;达到生态容量前后大亚湾生态系统的总初级生产量/总呼吸量变化很小(变化值为0.001),系统杂食性指数和系统连接指数均没有变化,因此认为放流黑鲷至生态容量对大亚湾生态系统的稳定性和营养结构未产生影响。     

基于Ecopath模型的大亚湾海域生态系统结构与功能初步分析

大亚湾是位于广东省东部的重要经济活动区域,渔业资源捕捞和航道运输等行为改变了其生态系统结构和功能,因此,评估和可持续利用渔业资源需要计算该生态系统各功能组之间的相互作用。该研究通过Ecopath with Ecosim(EwE 6.4)软件,利用2012年大亚湾海域渔业资源调查数据将大亚湾生态系统划分为18个功能组和1个碎屑组,整体了解该生态系统能量流动、总体特征和各食物网结构。研究结果表明:大亚湾生态系统各营养级呈现金字塔结构,营养级范围在1~3.29级之间。食物链通道主要有2条,一条为牧食食物链,另一条为碎屑食物链。大亚湾生态系统营养级转换效率较低,生态系统总转换效率仅为8%。大亚湾生态系统总流量为6 249.573 t·(km~2·年)~(-1),系统总生产量为2 827.584 t·(km~2·年)~(-1),总净初级生产量为2 468.36 t·(km~2·年)~(-1),总初级生产量/总呼吸量(TPP/TR)为2.185,Finn循环指数(FCI)和平均能流路径(MPL)分别为4.8%和3.53,联结指数(CI)和系统杂食性指数(SOI)分别为0.324和0.174。综上,大亚湾生态系统食物网简单,稳定性较差,系统处于幼期阶段,亟须加强捕捞限制和资源环境保护。     

基于Ecopath模型的20世纪80年代武汉东湖生态系统结构和能量流动研究

为了解1980s蓝藻水华等环境干扰期间武汉东湖生态系统的结构和特征,依据1980s武汉东湖生态环境及鱼类资源的调查数据构建东湖湖泊生态系统Ecopath模型,定量分析东湖生态系统食物网结构及能量流动特征。该生态系统模型由大型鲌类、其他肉食性鱼类、红鳍原鲌（Chanodichthys erythropterus）、杂食性鱼类、其他小型鱼类、浮游生物食性鱼类、虾类、底栖生物、浮游生物、大型沉水植物和碎屑等14个生物组分构成,基本覆盖整个东湖生态系统食物网。Ecopath模型结果表明,武汉东湖生态系统主要由4个整合营养级构成,鲢（Hypophthalmichthys molitrix）、鳙（Aristichthys nobilis）和浮游植物的营养转换效率很低。系统的香农多样性指数为1.47,说明系统在该时期的组分简单,抵抗能力弱;系统的循环指数为3.541%,远小于10%,说明系统整体的再循环能力低。系统的总初级生产量/总呼吸量（TPP/TR）、连接指数（CI）、Finn’s循环指数（FCI）、Finn’s平均能流路径长度（FML）和系统杂食性指数（SOI）分别为3.802 2、0.331...     

象山港生态系统结构与功能的Ecopath模型评价

为了解象山港生态系统在环境和捕捞等多重因素胁迫下的结构和功能现状,实现象山港基于生态系统的渔业管理和生态承载力评价,本研究根据2011~2014年在象山港开展的渔业资源和生态环境定点调查数据,利用Ecopath with Ecosim 6.4软件构建了象山港生态系统的Ecopath模型,并通过模型系统分析了象山港生态系统食物网结构、能量流动和系统功能的总体特征。模型包含了浮游植物、大型海藻、浮游动物、游泳动物等25个功能组,大体涵盖了象山港生态系统能量流动的整个过程。研究结果表明,象山港生态系统表达能流路径的食物链主要有两条,分别为牧食食物链和碎屑食物链,其中以牧食食物链为主要能流通道。系统中各功能组的营养级在1.00~3.62级。系统总能流为2 210 t·km-2·a-1,主要分布在Ⅰ~Ⅳ营养级上。流量中来自碎屑的比例为38%,初级生产者是系统能量的主要来源。营养级Ⅰ和Ⅱ的利用效率较低,大量初级生产力和次级生产力未能流入更高的营养层次。系统的总能量转换效率为3.8%;总初级生产量/总呼吸量(TPP/TR)为1.52;系统连接指数(CI)为0.342;系统杂食性指数(SOI)为0.182。生态系统总体特征反映了象山港生态系统的营养关系较简单,食物网复杂程度低;系统成熟度和稳定性偏低,抵抗外界干扰的能力较弱。     

大连旅顺渤海侧沿海虾夷扇贝幼虫来源调查

旅顺渤海侧沿海没有虾夷扇贝资源,但是每年的5月中旬-6月中旬出现虾夷扇贝幼虫,使该海域形成采苗场.2006-2007年笔者通过在虾夷扇贝主要增养殖海区投放漂流瓶跟踪移动方向,监测浮游幼虫数量及个体大小分布等方法,调查了旅顺渤海侧沿海虾夷扇贝幼虫来源.结果表明,2006年4月30日、2007年4月8日和4月28日,在獐子岛海域投放的漂流瓶,回收率分别为7.5%、14.0%和17.2%,其中在獐子岛至旅顺渤海侧沿海回收的比例分别为6.0%、10.4%和4.0%.2006年4月6日,大钦岛海域投放的漂流瓶,回收率为13.0%,在旅顺渤海侧回收率为0%.獐子岛至旅顺渤海侧沿海设置10～12个站位,调查浮游幼虫数量及个体大小分布,结果表明,进入5月中旬以后随着时间的推移,幼虫向旅顺渤海侧沿海集中,而且大个体幼虫的比例增加.调查结果证明,旅顺渤海侧沿海虾夷扇贝幼虫主要来自黄海北部增养殖海区.     

大连獐子岛海域虾夷扇贝养殖容量

现场测定了獐子岛海域的叶绿素a浓度、初级生产力的季节性变化和养殖虾夷扇贝的种群结构;采用生物沉积法,测定了不同规格的虾夷扇贝的滤水率和虾夷扇贝的基本生物学特性.调查结果显示,叶绿素浓度在1.23～2.85 mg·m-3范围内,均值为(1.78±0.57)mg·m-3;初级生产力的平均值为(76.6±41.9)mg C·m-2·d-1,虾夷扇贝单位个体的滤水率为(0.55±0.25)L·h-1.结合虾夷扇贝的年产量、海域面积和有关的水文状况等数据,计算了食物限制性指标的数值,摄食压力和调节比率在0.05和1.0之间,而滤水效率小于0.05.结果显示,由于该海域的叶绿素浓度和初级生产力水平较低,海水流速大,因此,水交换带来的悬浮颗粒物为主要食物来源.目前的虾夷扇贝的养殖量(32亿粒)接近生态容量,如果开展筏式养殖,利用整个海域的水体,养殖量增大20倍的空间并达到养殖容量,预计年产量将达到256亿粒.     

基于生态通道模型的鲥鯸淀生态系统营养结构和能量流动研究

利用 Ecopath with Ecosim (EWE)模拟生态系统能量通道模型, 比较分析了鲥鯸淀生态修复区和对照区的生态系统结构、食物网变化和能量流动特征。结果表明, 生态修复区同种鱼类营养级略低于对照区; 修复区牧食链与腐食链增加了鲇、鳜以及团头鲂、草鱼, 相比对照区更为复杂。生态修复区各营养级之间能量的转换效率( ~ Ⅱ Ⅱ依次为 0.0521、0.0205、0.0144)高于对照区( ~ Ⅱ Ⅱ依次为 0.0406、0.0138、0.00854), 且总能量转换效率(2.5%)也高于后者(1.7%)。生态修复区连接系数(0.22)略低于对照区(0.27), 但系统杂食性指数则相反(0.15>0.14); 生态修复区 Finn’s 循环指数(0.61)、Finn’s 平均路径长度(0.08)低于对照区(分别为 1.73、2.20)。两区域生态系统的总体特征表明, 生态修复区食物网结构更为复杂, 能量传递效率有所提高; 但生态系统的营养流经食物链的长度缩短了, 物质再循环的比例有所下降。同时, 生态修复区存在生产量大于呼吸量的情况, 鲥鯸淀区域应该适当放流肉食性、草食性鱼类, 定期捕捞滤食性鱼类, 增加生态系统的能量流动, 促进生态系统的良性发展。     

“冷水团”疑云笼罩獐子岛

<正>10月31日,獐子岛公司公告称,发现部分海域的底播虾夷扇贝存货异常,决定对105.64万亩海域底播虾夷扇贝存货放弃采捕,对43.02万亩海域的底播虾夷扇贝存货计提跌价准备2.8亿元,合计影响净利润7.6亿元,归属于上市公司股东的净利润巨亏最终修正为8.12亿元。据企业出示的专家调查报告,造成这一巨亏恶果的直接罪魁是自然灾害——冷水团,受此影响,预计2014年全年亏损。獐子岛股票于10月     

Atlantic Fisheries Technological Conference,Moncton, NB,August 21, 1995

No abstract available for this article.     

Anguilla huangi Teng, Lin, and Tzeng, 2009, is a junior synonym of Anguilla luzonensis Watanabe, Aoyama, and Tsukamoto, 2009

Anguilla luzonensis and A. huangi were each described in 2009 using eels obtained from northern Luzon Island. We examined the taxonomic status of these two groups of eels using morphological and molecular genetic characters. There were no significant differences in two vertebrae counts between eels of A. luzonensis and A. huangi. Mitochondrial 16S ribosomal RNA and cytochrome b genes sequences were obtained and compared among 28 specimens of A. luzonensis, the holotypes of A. luzonensis and A. huangi, and one specimen of the other 15 anguillid species. The specimens of A. luzonensis exhibited almost identical sequences, including the holotype, with only a few site differences, and the genetic difference between the holotypes of A. luzonensis and A. huangi was within the range of differences of specimens of A. luzonensis. The other anguillid species were genetically very different from A. luzonensis and A. huangi, although A. interioris is a closely related species. It is clear that A. luzonensis and A. huangi are the same species, and according to the principle of priority in zoological nomenclature, A. luzonensis Watanabe, Aoyama, and Tsukamoto, 2009 is the valid species name, and A. huangi Teng, Lin, and Tzeng, 2009 is a junior synonym of A. luzonensis.     

Age,growth, maturity and the overfishing of the iconic sciaenid,Argyrosomus japonicus,in south-eastern,Australia

Mulloway (Argyrosomus japonicus) occur in estuarine and coastal waters surrounding Australia, Africa, India, Pakistan, China, Korea and Japan, where they are important in fisheries. This study identified that mulloway in south-eastern Australia had similar growth rates, but matured at smaller lengths and younger ages, to those in South Africa and Western Australia. Growth of both sexes was similar to about 5 years, after which females grew faster and attained a greater maximum length than males. Female mulloway matured at 4–5 years of age with a L₅₀ of 68 cm, whereas males matured at 2–3 years of age with a L₅₀ of 51 cm. The commercial fishery in New South Wales was characterised by declining catches and a reduction in the proportion of mulloway of mature lengths in landings. During 2002–2005 commercial landings were dominated (83%) by fish within 15 cm of the current minimum legal total length of 45 cm and aged 2 and 3 years (>80%), even though mulloway can attain lengths of 200 cm and live >30 years. Estimates of the rates of instantaneous total mortality ranged between 0.34 and 0.45, whilst the rate of instantaneous natural mortality (M) was estimated to be approximately 0.12. Yield-per-recruit analyses indicated that mulloway in New South Wales are being growth overfished and substantial increases in yield could be achieved by increasing the length at first harvest. Values of the spawning potential ratio were below 0.2 under a range of mortality estimates, suggesting that mulloway are at risk of recruitment overfishing. These results suggest that the spawning stock of mulloway in south-eastern Australia has been depleted and that remedial management action is required to protect this iconic species.     

Surface disinfection of Pacific threadfin, Polydactylus sexfilis, and amberjack, Seriola rivoliana, eggs

The effects of exposing the eggs of Pacific threadfin and amberjack eggs (AEs) to different concentrations of hydrogen peroxide for 5 min on hatch rate and survival were assessed in a series of experiments using a petri dish model rearing system. Despite significant inter‐batch variation in hatch rate, it was shown that eggs of both species could be safely exposed to up to 11 340 mg L⁻¹ H₂O₂ for 5 min. Exposure to 34 230 mg L⁻¹ H₂O₂ for 5 min was shown to be lethal to AEs at a late stage of development. In two further experiments, it was demonstrated that Pacific threadfin eggs were resistant to all tested concentrations of a range of polyvinylpyrrolidone iodine (PVP‐I) concentrations and contact times (up to 1000 mg L⁻¹ PVP‐I for 10 min). The level of bacteria adhering to the eggs of both species was highly variable. Where eggs were heavily colonized (>10⁴ cfu egg⁻¹), hydrogen peroxide concentrations of at least 11 340 mg L⁻¹, or PVP‐I concentrations higher than 500 mg L⁻¹ for 10 min, were required for effective sterilization. In less colonized batches, rinsing in sterile seawater or exposure to lower (550 mg L⁻¹) concentrations of H₂O₂ was sufficient to result in high apparent levels of surface sterility (<1 cfu egg⁻¹).     

Effects of Mosquitofish,Gambusia affinis,on Channel Catfish,Ictalurus puncatatus,Production Ponds

Mosquitofish, Gambusia sp., have been spread throughout the world to biologically control mosquitoes. However, the fish has gained a reputation as an invasive species and has been implicated in displacing native aquatic species. Gambusia affinis are native to the southeastern United States and commonly occur in commercial channel catfish, Ictalurus punctatus, production ponds. We investigated effects of mosquitofish presence on zooplankton populations, water quality, disease occurrence, and fish production in experimental ponds. There were no differences between ponds with or without mosquitofish in numbers of calanoid copepods, cyclopoid copepods, total copepods, Bosmina sp., Ceriodaphnia sp., Moina sp., Daphnia sp., or total cladocerans. There were also no differences in copepod and cladoceran sizes. Copepod nauplii were more numerous during the summer months in ponds with mosquitofish. There were no differences in water quality variables (soluble reactive phosphorus, nitrate, nitrite, ammonia, total nitrogen, total phosphorus, pH) or phytoplankton density between ponds stocked with and without mosquitofish. Catfish production and disease occurrence were also similar between ponds with and without mosquitofish. Although mosquitofish may cause problems when stocked outside their native range, there does not appear to be any adverse effects of mosquitofish presence in catfish production ponds.     

Compositional differences,antioxidant activity,angiotensin-converting enzyme inhibition,and sensory characteristics of kamaboko fermented in wheat,rice, brown rice,and soybean koji

Fisheries Science - Fermentation of kamaboko in koji with wheat (KW), rice (KR), brown rice (KB), or soybean (KS) was performed by simulation of tofuyo processing. Moisture and protein content...     

Sperm Motilities in Waigieu Seaperch,Psammoperca waigiensis: Effects of Various Dilutions,pH, Temperature,Osmolality, and Cations

The objectives of this study were to evaluate the effects of varying dilutions, pH, temperature, osmolality, and cations on sperm motility parameters in waigieu seaperch, Psammoperca waigiensis. The maximum velocity of average in path (VAP), percentage of motile cells (MOT), and duration of sperm motility (DSM) were observed when semen was diluted in artificial seawater (ASW) at a ratio of 1:100 (144.9 ± 0.6 µm/sec, 95.6 ± 0.4%, and 230.3 ± 2.3 sec, respectively), at 30 C (142.0 ± 0.6 µm/sec, 93.6 ± 0.4%, and 238.3 ± 0.9 sec, respectively), and pH 8 (144.8 ± 0.6 µm/sec, 93.3 ± 0.4%, and 234.0 ± 1.5 sec, respectively). Maximum VAP, MOT, and DSM were obtained in each solution containing 0.6 M NaCl (143.8 ± 1.0 µm/sec, 91.3 ± 2.0%, and 230.6 ± 4.2 sec, respectively), 0.6 M KCl (135.1 ± 3.1 µm/sec, 91.1 ± 3.1%, and 230.3 ± 3.7sec, respectively), 0.2M CaCl₂ (105.3 ± 4.7μm/sec, 47.9 ± 2.7%, and 120.7 ± 1.3 sec, respectively), 0.2 M MgCl₂ (107.3 ± 3.0 m/s, 42.1 ± 3.3%, and 120.3 ± 4.8 sec, respectively), and osmolality of 400 mOsm/kg (145.1 ± 2.5 µm/sec, 93.0 ± 2.1%, and 346.5 ± 4.4s, respectively). We used these mediums as artificial insemination media for fertilizing matured eggs. The results showed that the fertilization and hatching rates in 0.6 M NaCl (75.3 ± 0.6% and 57.0 ± 2.4%, respectively), ASW (70.8 ± 1.2% and 51.2 ± 1.8%, respectively), or 400 mOsm/kg (72.9 ± 1.8% and 55.3 ± 1.6%, respectively) were higher than that in seawater (63.9 ± 1.2% and 39.2 ± 3.9%, respectively). In conclusion, using 0.6 M NaCl, ASW, or 400 mOsm/kg as an artificial insemination medium is effective for fertilizing of waigieu seaperch.     

驼背鲈(Chromileptes altivelis)的胚胎发育及仔、稚、幼鱼形态观察

对驼背鲈(Chromileptes altivelis)的胚胎发育及仔、稚、幼鱼的形态特征进行了详细的观察与研究,描述了从受精卵到仔、稚、幼鱼各发育期的时间和形态特征变化。结果表明,在水温25-26℃、盐度30的海水中,受精卵历时27 h 25 min完成整个胚胎发育过程,经历从卵裂、囊胚、原肠、神经胚到肌节形成、各器官的逐渐形成、变化、完善等一系列的胚胎发育和变化过程;根据其卵黄囊消长情况、鳞片的覆盖状态、体色发生的不同变化以及第二背鳍和腹鳍的消长,将胚后发育分为仔、稚、幼鱼3个阶段。在水温22-26℃、盐度29-31、DO≥5 mg/L的条件下,2-3 d仔鱼卵黄囊消失,开口摄食;生长发育至31 d,仔鱼已变态进入稚鱼期;培育至57 d,稚鱼完成变态,成为幼鱼。第二背鳍棘和腹鳍棘的生长与收缩等石斑鱼类早期发育的共性生长特征及其体表特性体色变化特征为驼背鲈胚后发育过程中最明显的特征。