基于声学映像的南奥克尼群岛海域南极磷虾集群特征

为确定南奥克尼群岛海域南极磷虾(Euphausia superba)集群特征,本研究根据2017年3-4月我国南极磷虾探捕项目采集的断面声学数据,使用通用声学数据后处理软件,研究了该海域的南极磷虾集群特征信息。本研究共检测并提取了2539个磷虾集群的高度、长度、分布深度、集群间距、集群面积及集群磷虾密度信息,其中白天集群1389个,夜晚集群1150个。通过集群特征值的统计,将该海域集群分为3类。聚类A的虾群密度最大[(19.24±27.00)ind/m~3],聚类B的虾群最深[(174.74±53.30) m],聚类C的虾群面积最大[(2868.62±2149.75) m~2]。聚类A和聚类B的集群长度无显著性差异(P0.05),聚类A和聚类C的集群深度无显著性差异(P0.05)。A类集群主要分布在南奥克尼群岛北部及西北部的深水区,水深1000 m。B类和C类集群在整个调查海域均有分布,其中B类集群多分布在群岛大陆架海域,水深200 m。不同区域的集群分布信息不同,离岛屿最远的东西两个断面集群较少,分布比较分散。本研究结果表明大部分的磷虾个体位于少数的大型集群中,集群磷虾密度和集群间距间存在正相关关系;未来通过磷虾集群与外界因子(环境因子,捕食者)相关性的研究,可以帮助我们更为准确地了解集群结构与形成机制,预测磷虾资源分布。     

2018年夏季南奥克尼群岛南极磷虾集群特征

基于2018年夏季南奥克尼群岛南极磷虾资源声学调查数据,本研究对该海域南极磷虾集群进行了分析。结果显示,检测到南极磷虾集群3 224个,反映集群特征的5个参数即深度、长度、厚度、面积及密度分别为(96.00±64.33) m、(218.52±455.66) m、(11.19±13.98) m、(1 894.40±9 345.72) m2和(114.11±159.60)尾/m³;不同时间段之间集群密度无显著性差异,但集群深度、长度、厚度及面积之间均存在显著性差异。不同水层间集群厚度和面积之间无显著性差异,但集群深度,长度和密度均存在显著性差异。南极磷虾集群共分为三类,其中第Ⅰ类集群密度最大,为(325.90±221.30)尾/m³;集群规模最小,为(379.64±433.73) m²;深度最深,为(158.06±67.54) m。第Ⅱ类集群的长度最长,为(1 089.60±1 189.56) m;集群面积为(15 601.25±30 243.33) m²,远大于其他集群。第Ⅲ类集群深度最浅,为(78....     

南极南奥克尼群岛2017年春季南极磷虾资源声学评估

南极磷虾（Euphausia superba）为南大洋中上层生态系统的关键种,对其生物量的研究有助于更准确地掌握磷虾的生态和分布信息。基于2017年我国南极磷虾声学调查采集的断面回波映像,应用声学回波后处理软件（Echoview）,评估了南奥克尼群岛周边水域的磷虾生物量。该海域磷虾体长范围为25.50~49.21 mm,平均体长为（33.01±4.06）mm;其中雌性平均体长为（33.15±3.90）mm,雄性平均体长为（32.68±4.43）mm,雌、雄磷虾体长无显著性差异。本海域声学映像可分为1338个积分单元,最大单元磷虾密度为554.07 g/m²,最小单元密度值为0 g/m²。调查海域磷虾分布不均匀,87.90%的积分单元无磷虾生物量。磷虾平均密度为71.01 g/m²,总生物量为1.77×10⁶ t,密度差异系数为97.4%。磷虾主要分布在水深<200 m的南奥克尼群岛大陆架海域,群岛东侧磷虾生物量多于西侧。积分单元中磷虾密度大于450 g/m²但小于600 g/m²的有2个,群岛东西两侧各1个;密度值大于300 g/m²但小于450 g/m²的积分单元有6个,5个位于群岛东侧。远离群岛的2个断面（1,9）和调查海域中心的2个断面（5,6）磷虾生物量较少。本海域磷虾的昼夜垂直移动对磷虾生物量评估也无影响。磷虾白天聚集在60~180 m水层,随着时间推移,磷虾逐渐向上或向下移动。光照强度是触发磷虾白天下沉、夜晚上浮的因素之一。     

2019年秋冬季南设得兰群岛南极磷虾集群时空分布特征

为了进一步研究南设得兰群岛附近海域南极磷虾集群时空分布特征,基于2019年秋冬季（4—7月）中国南极磷虾生产渔船声学调查及商业捕捞数据,从时空两个维度对南极磷虾集群中心深度、集群所处水深水温和集群形态进行了分析。结果显示,南设得兰群岛附近海域南极磷虾集群中心深度、集群所处水深水温和集群形态存在明显的时空差异。平均集群中心深度在4—7月总体呈递增趋势(变化范围为34.39～86.12 m),昼夜差异较小(P=0.325),峰值时段为日升阶段(sun rising, SRS)(64.06 m)和夜间(night, NIT)(65.32 m);平均集群中心深度低值区间为62.75°～63.75°S和58.25°～59.75°W,高值区间为61.75°～62.25°S和60.25°～61.75°W。平均集群所处水深水温在4—7月总体呈递减趋势(变化范围为-1.71～-1.50℃),昼夜集群水温差异明显,峰值时段为NIT(夜间)(-1.46℃)和暮光(evening twilight, ETW)(-1.4℃);平均集群所处水深水温低值区间为62.75°～63.75°S和61.25°～61.75°...     

2017年秋季南奥克尼群岛海域南极大磷虾垂直分布与光照及垂向温盐关系

为了解南极大磷虾(Euphausia superba Dana)行为变化规律,基于2017年3月25日—4月3日在南奥克尼群岛海域43个站位点收集的声学和CTD数据,提取250 m以浅水层南极大磷虾群的深度和对应的温、盐信息,分析不同光照条件下南极大磷虾昼夜垂直分布特征。结果显示:黎明时段(6∶00—8∶00)磷虾群分布较分散,20～60 m(35.72%)和200 m以深(33.65%)虾群相对较多;白天时段(8∶00—16∶00)磷虾群则较多分布在40～120 m(58.52%)水层,多聚集在温跃层(54.55%)和盐跃层(63.64%)内;黄昏时段(16∶00—18∶00),温盐跃层内虾群减少;夜间时段(18∶00—次日6∶00)磷虾群主要分布在20～40 m(49.55%)和180 m以深(31.51%)两个水层,多聚集在温跃层(75%)和盐跃层(70%)外。本研究结果有助于进一步了解南极大磷虾的迁徙规律和资源分布。     

南极半岛周边海域南极大磷虾生物学 特性的初步研究

根据2010年1月24日-2月11日在南极半岛周边CCAMLR辖区48.1区和48.2区的拖网磷虾渔获数据,对南极大磷虾的生物学特性进行了初步分析.结果表明:两区南极大磷虾的体长范围为33.65～ 65.80 mm,优势体长为50.00 ～58.00 mm,占60.66％;平均体长48.1区略大于48.2区,雌性大于雄...     

南极磷虾及磷虾渔业

本文主要介绍南极磷虾的生物学和生态学特点,南极磷虾的地理分布和南极磷虾渔业及磷虾利用的前景.     

2018年夏季南奥克尼群岛南极磷虾资源丰度多尺度空间异质性

南极磷虾是南大洋中上层生态系统的关键物种,也是我国远洋渔业的重要捕捞对象,充分了解其空间分布特征可为南极磷虾资源的持续开发和利用提供理论支撑.基于2018年夏季南奥克尼群岛南极磷虾资源声学调查数据,将研究海域按经纬度划分为7个空间尺度,利用地统计学方法研究不同尺度下南极磷虾资源丰度的空间异质性特征.结果 显示:①随着空...     

南极磷虾及磷吓渔业

本文主要介绍南极磷虾的生物学和生态学特点,南极磷虾的地理分布和南极磷虾渔业及磷虾利用的前景。     

南极磷虾产品研究及发展趋势

南极磷虾生活在南极海域,资源量丰富,具有较高的应用价值.南极磷虾开发耗资巨大,在大规模商业性开发投入之前,做好相关产品与市场分析等基础工作十分必要.本文首先对南极磷虾产品的发展历程进行了分析,继而对南极磷虾产品的主要形式与发展前景进行了剖析,并对主要目标市场进行了定位研究.研究认为：南极磷虾粉和液态磷虾油是目前较为普遍的产品存在形式.其中,磷虾粉可作为蛋白质增强剂、增味剂和重要的氨基酸补充剂使用,可作为渗透调节之用,同时,可以作为矿物质来源、脂质来源、几丁质/几丁聚糖免疫增强剂、天然色素（类胡萝卜素）来源使用.磷虾粉的目标市场更倾向于水产饲料;磷虾油的目标市场主要倾向于营养保健和制药行业.相对于磷虾粉,磷虾油的市场价值更高.     

南极半岛南极磷虾栖息地适应性研究

南极磷虾(Euphausia superba)作为南极生态系统中的关键物种,其时空分布研究对发展磷虾渔业和理解南大洋生态系统均有重要的作用,相关研究有利于磷虾种群的资源评估以及中心渔场的探测。本文利用海表温度（Sea Surface Temperature,SST）、海面高度（Sea Surface Height,SSH）、海表面叶绿素（Sea surface chlorophyll,SSC）、海冰面积覆盖(Sea Ice Coverage,SIC）等环境因子,分别采用神经网络拟合和一元非线性拟合方法,并结合最小值法、最大值法、连乘法、算术平均法、几何平均法、加权算术平均法等构建了磷虾栖息适宜指数 (Habitat Suitability Index,HSI) 模型。结果表明,神经网络模型预报结果更符合磷虾实际栖息分布情况,而一元非线性拟合预测结果较为连续。最大值法和最小值法计算结果差异较大,容易引进较大的误差。连乘法的预测效果较好,算术平均法、几何平均法和加权算术平均法的预测结果相似,且较为稳定。     

Oceanographic variability and changes in Antarctic krill (Euphausia superba) abundance at South Georgia

Oceanographic data collected to the north of South Georgia were examined for three consecutive summers (1996/97, 1997/98, 1998/99). The results show the existence of a shelf break front during each period. The most reliable means of defining the front was the potential density anomaly at the near‐surface potential temperature minimum. In each year, off‐shelf waters were separated from on‐shelf waters by water with a potential density anomaly between 27.22 and 27.29 kg m^?3. During 1997/98, the near‐surface potential temperature minimum was much colder and much shallower than in other years and was consistent with waters originating from much further south than South Georgia; these differences were further evident at a single deep off‐shelf station. The oceanographic changes during 1997/98 were consistent with a mesoscale or large‐scale movement of the southern Antarctic Circumpolar Current front. Acoustically determined densities of Antarctic krill, Euphausia superba, at South Georgia showed consistent patterns between years. Densities were substantially higher over the shelf compared with off‐shelf, with the highest densities at the shelf edge; densities were also higher to the east of the island. During 1997/98, acoustic densities of krill were substantially higher than in other years. The coincidence of the elevated acoustic density and the cooler oceanographic conditions was explored. When data from all years were combined and analysed by Generalized Additive Model, an inverse relationship between acoustic density and temperature was apparent. Historical data were also examined and it was noted that the only other occurrence of such a high estimate of krill density at South Georgia, was when oceanographic conditions were also colder.     

南极大西洋扇区南极磷虾渔获率序列的振荡模态分析

为了解释南极大西洋扇区的48区南极磷虾(Euphausia superba)资源的多尺度振荡模态特征及其与环境振荡之间的响应关系, 采用经验模态分解方法, 对1982-2011年间的南极磷虾月均渔获率进行了分析。结果表明, 其振荡表现出了0.5 a、1 a、1.5 a、2.5 a、7 a和11 a等多个周期, 其中高频振荡对南极磷虾资源变动影响较大, 低频振荡影响较小; 3个亚区渔获率都为冬高夏低季节性振荡, 48.1~48.3亚区最高值依次出现在5月、 6月和9月, 渔获率的最低值出现在1月; 所有振荡周期中以1 a为最主要振荡周期(方差解释率为46.7%), 南极磷虾年补充规模对其渔获率最为重要; 其2.5 a振荡和海冰面积3.0 a;振荡有关; 渔获率低频振荡周期与气候-海流系统振荡周期有关。海冰面积和渔获率有较好的正相关关系(相关系数为0.44, 位相差10个月)。海冰面积异常振荡会在8~11个月之后对渔获率和渔获率异常产生的正相关影响。磷虾资源的振荡是环境振荡和磷虾生物周期综合作用的反映。

     

Evaluation of Antarctic krill (Euphausia superba) meal supplementation in diets for olive flounder (Paralichthys olivaceus)

The supplemental effect of Antarctic krill meal (KM) into a low fish meal (FM) diet was evaluated for olive flounder (Paralichthys olivaceus). A 56% FM‐based diet was regarded as a high FM inclusion diet (HFM), and a low‐FM diet (LFM) was prepared by replacing 50% FM from the HFM. Four other diets were prepared by supplementing 3%, 6%, 9% and 12% KM into the LFM diet gradually replacing soy protein concentrate and tankage meal (designated as KM3, KM6, KM9 and KM12 respectively). Quadruplicate groups of fish were fed one of the diets for 12 weeks. The growth performance and feed utilization efficiency were improved by the dietary KM supplementation. Digestibility of dietary protein and dry matter was increased by the KM3‐9 diets. Haematocrit and haemoglobin were increased by KM supplementation. The innate immunity and antioxidant capacity assessed by Ig, antiprotease, lysozyme, GPx and SOD and the condition factor of fish were significantly increased by KM3‐9 diets. Moreover, goblet cell counts, villi length and fillet yield of fish were significantly improved by all the KM‐containing diets (KM3‐12). A 25‐day‐long challenge test with the Edwardsiella tarda pathogen showed that the cumulative mortality was higher in fish fed the LFM diet than in fish fed the HFM or KM‐supplemented diets. The results indicate that dietary KM supplementation in a LFM diet can increase growth performance and feed utilization efficiency, diet digestibility, intestinal development and functions, innate immunity and disease resistance of olive flounder. The recommended level of KM inclusion in a LFM diet seems to be 6.6% according to quadratic regression analysis.     

Antarctic krill (Euphausia superba) meal in the diets improved the reproductive performance of tongue sole (Cynoglossus semilaevis) broodstock

A three‐month feeding trial was conducted to investigate the effects of dietary krill meal on the reproductive performance of tongue sole broodstock. Three diets were formulated to contain different levels of krill meal, 0 (Diet K‐0), 10 (K‐100) and 200 (K‐200) g kg^–1 dry matter, replacing the corresponding contents of protein and lipid from fishmeal and fish oil. Each diet was assigned to triplicate tanks. Compared with K‐0, both K‐100 and K‐200 increased the egg properties such as buoyant eggs rate, egg diameter, oil droplet diameter and SOD activity of the fertilized egg. However, the maturation rate, serum estradiol content, the relative fecundity and hatching rate were improved only by K‐100. The krill meal supplementation increased the concentrations of astaxanthin and n‐3 fatty acids in eggs, but decreased the n‐6 fatty acid concentrations. Both K‐100 and K‐200 increased the survival activity index, but the larval deformity rate was decreased only by K‐100. At 15 DPH, the larval length and the digestive enzyme activities were significantly higher in group K‐200 compared with groups K‐0 and K‐100. In conclusion, dietary supplementation of krill meal, at the level of 100 or 200 g kg^–1 dry matter in exchange of fishmeal and fish oil had the considerable positive effects on C. semilaevis reproduction.     

南极大磷虾木瓜蛋白酶酶解产物氟浓度及营养成分研究

为了解酶解处理对南极大磷虾木瓜蛋白酶酶解产物（上清干物质KSF,沉淀干物质KS和残渣KR）中氟浓度的影响,采用氟选择电极法对酶解产物中氟进行测定。同时,采用国标方法对KSF和KS中主要营养成分进行测定。结果：KR中氟浓度最高,且KR中氟占酶解前基质中总氟的质量分数为72.94%~79.94%,而KSF和KS中氟浓度得到极大的降低。木瓜蛋白酶加入有利于虾浆中不溶的蛋白质以可溶解的形式进入上清液中。KSF中未检测到粗脂肪,总糖含量为13.91%~21.57%,粗蛋白含量为57.75%~67.13%。而KS中粗脂肪含量高达33.28%~42.90%,总糖10.14%~15.57%,粗蛋白38.00%~44.87%。因此,木瓜蛋白酶酶解南极大磷虾获得的KS和KSF均可以作为优质、安全的饲料添加剂。其中,添加1.5%的木瓜蛋白酶和1.0%葡萄糖,经58℃水浴3 h的酶解方式能使KSF的得率从18.65%上升到20.37%,其粗蛋白含量为65.49%,而KS的粗蛋白和粗脂肪含量分别为39.16%和38.49%,为最佳的酶解南极大磷虾的酶解方式。