黄海北部中国对虾合理放流数量的讨论

在黄海北部放流虾的渔获量(y 百万尾)与放流数量(x 亿尾)之间有着统计学上可置信的关系,α=0.05,用 y=ax+bx~2描述,a=14.63,=0.45。最大放流量为16亿尾,最佳经济放流量为15亿尾(计数误差20%)。在目前条件下,我们认为控制放流量在11亿尾(计数准确率90%)是合理的。预测了前景,提出了可供选择的方案。     

三疣梭子蟹活蟹肉的冷冻加工技术

三疣梭子蟹是深受市场欢迎的水产品，但是储运困难，容易变质走味，如何在低温条件下对三疣梭子蟹进行保存，是许多科技工作者研究的重要课题，本文论述了三疣梭子蟹活蟹肉的冷冻加工工艺，对加工要点和品质鉴定作了说明。     

Validation of multi-frequency inversion method by using dummy scatterers of zooplankton

ABSTRACT:   High- and multi-frequency acoustic measurement systems and the multi-frequency inversion (MFI) method have been used to measure spatial distributions and abundances of zooplankton by size. In this study, the calibration method for high- and multi-frequency systems was developed and the validation of MFI method was carried out by scatterer measurement. The standard sphere calibration method that has not been applied to such high- and multi-frequencies was applied to calibrate our high- and multi-frequency system, TAPS-6 (Tracor Acoustic Profiling System, BAE Systems). An optimum size of standard sphere of tungsten carbide of 1 mm radius was derived to have a small target strength variation for the six frequencies of TAPS-6, and the practicability and precision of the standard sphere calibration method was confirmed for those frequencies. A school or cluster of dummy scatterers of zooplankton with small tungsten carbide spheres were designed to validate the MFI method, and volume back-scattering strength values were measured by the multi-frequency system. By comparing the result of the inversion with their real composition, the features of the MFI method could be validated and examined.     

基于局部化双向LSTM和状态转移约束的养殖水质分类预测

养殖水质对水产养殖的产出和收益具有非常重要的影响,提前预测水质状况可以提高治理水平,从而减少水产养殖的损失。以南美白对虾(俗称白肢虾)日常养殖水质为研究对象,选取温度(T)、pH、溶氧(DO)、盐度、氧化还原电位(ORP)、亚硝酸盐氮(NO^-_2-N)和氨氮(NH^+_4-N)作为水质数据特征,提出基于局部化双向LSTM(CovBiLSTM)和状态转移约束的水质预测模型(CovBiLSTMST)。首先使用双向LSTM网络接收历史水质数据序列信息的输入,然后利用卷积函数和最大池化技术(Max pooling)来挖掘双向LSTM网络不同单元输出数据之间的关系,对历史不同时间的水质数据进行融合,最后采用Softmax分类器来预测水质状况,同时利用状态转移约束条件来提高预测的准确率。通过对比试验,分别证明了局部双向化LSTM和状态转移约束对水质预测的有效性。与基于LSTM的预测方法相比,评价指标分类准确率和召回率分别提高5%和4%。研究表明:基于局部化双向LSTM(CovBiLSTM)网络模型的水质预测算法比基于其他模型的预测算法能更准确预测南美白对虾的水质状况。     

Brown shrimp (Farfantepenaeus aztecus) density distribution in the Northern Gulf of Mexico: an approach using boosted regression trees

The estuarine‐dependent brown shrimp, Farfantepenaeus aztecus, is a significant commercial fishery and important species in the Gulf of Mexico (GOM) ecosystem as well as being a key component in energy transfer between benthic and pelagic food web systems. Because of the economical and ecological importance of brown shrimp, we developed a spatial population model to identify places of high shrimp density under a set of spatial, environmental and temporal variables in the Northern Gulf of Mexico (NGOM). We used fisheries‐independent data collected by the Southeast Area Monitoring and Assessment Program (SEAMAP) from 1992 to 2007 (summer and fall seasons). The relationship between the predictor variables and shrimp density was modeled using Boosted Regression Trees (BRT). Within the environmental variables included in the model, bottom type and depth of the water column were the most important predictors of shrimp density in the NGOM. Spatial predictions performed using the trained BRT model for summer and fall seasons showed a spatial segregation of shrimp density. During the summer, higher densities were predicted near the Texas and Louisiana coast and during the fall, higher densities were predicted further offshore. The model performed well and allowed successful prediction of brown shrimp hot spots in the NGOM. Model results allow fisheries managers to evaluate the potential impact from fisheries on the resource and to develop future fisheries management strategies, understand the biology of brown shrimp as well as assess the potential impacts of oil spills or climate change.     

皱纹盘鲍的底播增殖试验

1987～1990年在长海县獐子岛近海水域,采用人工培育的平均壳长为20mm(12～34mm)的幼鲍进行底播,3周年后,平均壳长达77.5mm,平均体重达64.7g,成活率为46.9%。试验证明,底播幼鲍的规格与其成活率密切相关,适宜规格为壳长20～25mm,最小规格为18mm。讨论了回捕率的调查方法,以及幼鲍底播规格与中间育成在时间上的衔接等问题。     

草鱼含信号肽分泌蛋白的预测分析

采用组合的信号肽分析软件SignalP 3.0,TMHMM 2.0,big-PI,TargetP 1.1和Lipop 1.0对已公布的522个草鱼ORF编码蛋白的N端氨基酸序列进行信号肽分析,同时系统分析了信号肽的类型及结构。结果表明,522个草鱼氨基酸序列中分泌蛋白有61个,占其基因组编码蛋白的11.7%。编码这些蛋白的可读框(ORF)最小值为127 bp,最大值为5032 bp,平均910 bp,引导它们的信号肽长度介于15～32个氨基酸之间,平均为21个氨基酸。通过对草鱼分泌蛋白切割位点信号肽类型分析发现具Ⅰ型信号肽的分泌蛋白有17个,Ⅱ型的有4个。草鱼分泌蛋白中,42个具可预测功能,19个为未知功能蛋白。已知功能的分泌蛋白主要集中于细胞代谢,细胞调控及转运,细胞膜结构,细胞的免疫等领域。     

冷却链大黄鱼货架期预报系统的开发与评估

通过使用Visual Basic编程语言,完成了基于0~10℃腐败希瓦氏菌生长动力学模型建立的冷却链大黄鱼货架期预报系统的设计,验证了货架期预报系统的准确性。采用以自然污染鱼得到的实验数据建立特定腐败菌生长动力学模型的方法,提高了预测的准确性,腐败希瓦氏菌和剩余货架期预测值与实测值的可靠性评估表明,其相关系数R2分别为0.936和0.935,显示开发的冷却链大黄鱼货架期预报系统可以快速可靠地预测冰鲜大黄鱼的鲜度与剩余高品质期和货架期。系统开发过程中采用免安装处理,方便用户使用。     

西北印度洋大眼金枪鱼渔场预报模型建立与模块开发

根据1990—2003年印度洋大眼金枪鱼延绳钓渔业数据和美国国家海洋和大气管理局提供的海表温度、叶绿素-a历史环境数据,应用环境因子叠加方法,构建了西印度洋大眼金枪鱼渔场预报模型,用于金枪鱼渔场预报。分析得出各月适宜海表温度、叶绿素-a浓度范围和历史高产区空间位置;导入实时海表温度、叶绿素-a等遥感栅格数据,分别提取适宜海表温度、适宜叶绿素-a浓度和历史高产区的空间栅格数据集,最后在空间上对3种栅格数据进行空间叠加并取交集。交集所指空间区域即为大眼金枪鱼潜在渔场位置。通过精度检验,表明该模型渔场预报精度为60.5%。并以VC++6.0工具为开发平台,对此模型进行了设计开发,实现了模块预报西北印度洋大眼金枪鱼渔场。     

对我国渔具分类标准的探讨

随着渔业科学技术日益发展、学术交流日益频繁以及全国渔具准入标准制订和实施工作不断推进,我国现有的渔具分类国家标准《渔具分类、命名及代号》(GB/T 5147-2003)在对渔具的具体分类上存在的一些问题也逐渐显现。本文通过对比我国渔具分类国家标准和FAO渔具统计分类国际标准(ISSCFG),分析了两个标准在渔具分类的定位、具体分类等方面的区别和联系,并结合笔者在教学和科研实践活动中所遇到的国家标准在"类"、"型"和"式"方面可能存在欠缺完整性、灵活性、适应性、区分缺乏统一依据等问题,提出了对我国现有渔具分类国家标准进行修订等建议,以期加快对现有国家标准的复审和修订,维护国家标准的权威性,并使各项渔业管理工作具有统一的标准。     

村干部补贴标准研究——以陕西省兴平市为例

目前大多数村干部补贴收入水平偏低，通过对陕西省兴平市村干部的抽样调查，村干部月平均补贴仅为126元，低于当地农民人均纯收入，影响了村干部工作的积极性。通过调查，村干部对补贴的平均期望值为650元，村民愿意付给村干部补贴水平为306元。通过研究，我们认为村干部的补贴收入若为当地农民人均纯收入的3倍，则较为合理。     

Density-dependent growth of young-of-the-year Atlantic salmon (Salmo salar) revisited

Imre I, Grant JWA, Cunjak RA. Density-dependent growth of young-of-the-year Atlantic salmon ( Salmo salar ) revisited. Ecology of Freshwater Fish 2010: 19: 1–6. © 2009 John Wiley & Sons A/S
Abstract –  The length of individual young-of-the-year (YOY) Atlantic salmon ( Salmo salar ) in Catamaran Brook decreases with increasing population density following a negative power curve. Because most of this decrease in growth rate occurs at low densities (<1 fish·m⁻²), ( Imre et al. 2005 ; Journal of Animal Ecology, 74: 508–516) suggested that exploitation competition for drifting prey rather than space limitation might be responsible for this pattern. Recently, ( Ward et al. 2007 ; Journal of Animal Ecology, 76: 135–138) showed that the negative power curve of growth rate versus density can be caused by other mechanisms and suggested that Imre et al.'s evidence for density-dependent growth would have been stronger if we had analysed final size versus initial density rather than final density. We examined (i) whether the negative power curve of size versus density was also apparent in an analysis of final size versus initial density and tested two predictions that emerge from Ward et al.'s model, (ii) the variance in body size increases with population density, and (iii) the maximum fish size at a site is density-independent. The final size of YOY salmon decreased with increasing initial density following a negative power curve. Our data did not provide strong support for the above predictions emerging from Ward et al.'s model. Our analyses of different years, sites and seasons were consistent with the hypothesis of density-dependent growth of YOY salmon.     

Sampling error resulting from depth-dependent plankton distributions and current differentials in a two-layered system

We evaluate a source of error observed in standard ichthyoplankton bongo tows in which volumes of water filtered did not result in increased catches of red-fish. Our analyses demonstrate that, under conditions where redfish larvae are distributed in surface waters in a two-layered system, current differentials between surface and subsurface layers resulted in biased, standardized estimates of larval abundances as a result of filtering varying amounts of subsurface waters. Analysis of standard survey results on Flemish Cap demonstrated that this source of bias was limited to the May-June period, after waters became stratified and before redfish passed from the larvae to pelagic juvenile stage. Correcting for this source of sampling bias wIII result in more accurate absolute estimates of ichthyoplankton abundance, and we estimate that variation (CV) for replicate samples may be reduced by 10%.     

光合细菌培养基配方的优化研究

光合细菌培养基的组分是由乙酸钠、氯化铵、磷酸二氢钾、硫酸镁、酵母膏等5种原料构成。采用L16(45)正交表,将5种原料作为光合细菌生长有影响的因素,通过试验数理统计的直观和理论分析,对其配方进行优化。试验结果表明,当培养基的配方为乙酸钠3.3 g/L、氯化铵0.6 g/L、磷酸二氢钾0.9 g/L、硫酸镁0.5 g/L、酵母膏1.5 g/L、光照3 000 lx和温度(32±2)℃时,培养72 h即可达到生长峰值,细菌总数可以从起初的1.75×109cfu/mL提高到3.19×109cfu/mL。优化的培养基条件能有效促进光合细菌生长。     

对贝类产品标准中重金属限量指标的探讨

对我国现行的国家标准、行业标准及国外相关标准中有关贝类重金属的指标进行比较分析。在此基础上,结合我国目前贝类卫生状况调查结果以及国内外文献资料,对我国贝类标准中的重金属限量进行探讨,提出我国贝类标准中重金属的建议限量指标为:汞0.5 mg/kg,无机砷1.0 mg/kg,铅1.5 mg/kg,镉2.0 mg/kg(不包括牡蛎、扇贝、泥蚶),铜50 mg/kg,铬2.0 mg/kg。     

基于不同密度SNP面板的凡纳滨对虾AHPND抗性基因组预测准确性分析

为评估不同SNP标记密度对凡纳滨对虾AHPND抗性基因组预测准确性的影响，本实验对26个全同胞家系进行Vp AHPND侵染，收集686尾个体的存活时间数据，对其中242尾个体利用液相芯片“黄海芯1号”(55.0 K SNP)进行基因分型，基于A、G和H亲缘关系矩阵估计Vp AHPND侵染后存活时间的遗传参数；采用随机和等距抽取方式，基于55.0K SNP构建了8个低密度SNP面板(40.0、30.0、20.0、10.0、5.0、1.0、0.5和0.1 K)，利用GBLUP和ssGBLUP等方法预测Vp AHPND侵染后存活时间的基因组育种值，利用交叉验证方法计算其预测准确性，并与BLUP方法进行对比分析。遗传参数估计结果显示，Vp AHPND侵染后存活时间表现为高遗传力水平，估计值为0.68～0.79。在55.0 K SNP密度下，针对242尾基因分型个体数据集(G242)，利用BLUP、GBLUP和ssGBLUP方法获得的预测准确性分别为0.424、0.450和0.452,GBLUP和ssGBLUP比BLUP分别提升了6.13%和6.60%；针对686尾表型测定个体数据集(P686)...     

中国渔船标准化发展进程概述

回顾了中国渔船标准化发展基本进程,分析了不同时期的关键进展;统计分析了现行相关标准和规范体系,探讨了中国渔船标准和规范存在的问题;归纳总结了中国渔船结构强度和稳性、水动力和运动性能、节能减排、新型材料应用等领域的研究成果,以探寻渔船技术研究的方向。中国渔船标准化在标准船型评选、标准和规范制定、渔船相关技术研究等各个领域上取得了重要成果,为渔船的安全性、经济性、舒适性、耐波性和高效性提供保障;但存在渔船船舶行业标准和规范滞后、相关技术探讨较少较浅、先进技术和设备普及应用较慢等问题。渔船标准化是一项长期而艰巨的任务,不但要加大渔船的研究力度,加快渔船相关标准和规范的制定,还要相关政策制定部门的大力支持,才能不断完善中国渔船标准化建设。     

我国企业内部控制存在的问题及对策

内部控制制度在企业内部管理监控系统中起着举足轻重的作用,然而,对我国来讲全面认识内部控制还刚刚开始。文章分析了当前企业内部控制制度广泛存在的诸多问题,如缺乏公认的标准、制度不完善、法人治理结构不完善等,并针对这些问题提出了建立内部控制标准体系、加强会计基础工作、加强企业内部审计等对策。     

几种主要淡水鱼类温度基准值的研究

为保护水域生态环境的平衡，合理利用水资源和为制定发电厂热水排放的温度标准，提供有关水生生物的温度基准值，对青鱼、草鱼、链、镛和鲤等七种主要淡水经济鱼类作了温度基准值的研究，提出了最适生长温度，最大致死温度及短期暴露最大高温度基准值，以作为确保水生生物能正常生长与繁殖情况下，环境温度的评价标准，研究结果经鉴定确认可以作为制定渔业用水区温水排放标准的依据，同时也对温水或温流水养殖的管理有参考意义。     

水产标准编写的基本要求

标准的必备要素包括封面、前言、名称、范围、正文.水产标准由渔业环境、资源、渔船、水产养殖、水产品加工、渔具与渔具材料、渔业机械、仪器、渔用饲料、检疫防疫、渔药等标准组成,主要应用于水产品的养殖、捕捞、加工、运输、贸易等环节.介绍了水产标准编写中的必备要素及可选要素,提出水产标准编写的基本要求.