首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 109 毫秒
1.
黑龙江水系界江界河界湖渔业资源数据库的设计和建立   总被引:3,自引:0,他引:3  
在2001~2002年对黑龙江水系界江界河界湖渔业资源调查的基础上,通过与相关文献资料进行比较分析,并对数据资料进行整理和补充,建立了渔业资源数据库。利用Basic语言编程实现渔业资源评估等数据处理分析功能。应用Foxpro编程系统和API接口,实现对数据库的管理和对数据库功能的调用,形成了黑龙江界水域渔业资源数据库系统,系统具有数据的再输入、修改删除、查询检索、分析处理、输出打印等功能。  相似文献   

2.
东海区海洋渔业资源近况浅析   总被引:20,自引:2,他引:18       下载免费PDF全文
根据渔获产量统计和鱼类生物学资料对东海区海洋渔业资源动态作了分析。结果表明:近几年东海区海洋渔业捕捞产量虽连年增长,但主要是靠大幅度提高捕捞强度等措施获得。渔获物中增加的主要是经济鱼类的幼鱼和低值小杂鱼类,渔获物小型化、低龄化等过度捕捞现象仍然十分严重。渔业资源结构日趋恶化,渔业资源状况并没有明显改善。  相似文献   

3.
2004年夏季东海区带鱼资源状况及其秋冬汛渔况的分析   总被引:1,自引:0,他引:1  
东海带鱼为我国最重要的捕捞对象之一,其产量多年来一直位居我国海洋捕捞鱼类产量的首位。由于6月~9月是东海带鱼的繁殖与索饵盛期,因此,自1995年以后伏季休渔制度实施以来,每年的伏季休渔期间,带鱼群体得到了有效的生长和补充,伏季休渔结束后,渔获产量显著提高。本文以东海区渔业资源动态监测调查资料为依据,对2004年东海区伏季休渔期间带鱼资源状况进行了分析,并预测了秋冬汛的带鱼生产趋势。一、研究材料与方法利用1999年~2004年东海区渔业资源动态监测网重点渔场的常规监测和大面定点调查的资料,对历年的夏季带鱼资源密度、…  相似文献   

4.
一、东海区渔业资源区域合作管理与共同养护的必要性长期以来,由于东海区集中了强大的捕捞能力,对渔业资源的捕捞量超过了其再生能力,导致资源总体上出现严重衰退。主要表现为:鱼类个体小型化、低龄化和性早熟现象非常明显;渔获物中传统经济鱼类的比例下降,低龄鱼、低质鱼和杂鱼成为了主要的捕捞对象;单位捕捞努力量渔获量(Catch per unit effort,CPUE)下降,渔获物的平均营养级降低。说明有必要加强对东海区渔业资源的养护与管理,减少对资源的开发力度。中、日、韩三国作为共同开发利用东海区渔业资源的国家,理应承担起养护和管理东海区渔…  相似文献   

5.
东海区主要渔业资源利用状况的分析   总被引:17,自引:3,他引:14  
本文根据东海区渔业资源调查和区划、东海大陆架生物资源与环境和全国渔业统计年鉴等资料,统计1956~2002年东海区捕捞品种中经济价值较高、在渔业中占重要地位的11个种类的产量,并利用数理统计学上的主成分分析方法,分析研究了东海区11个主要捕捞种类历年来的资源变动特征、资源利用状况及其变动趋势。结果表明:11个主要捕捞种类的渔业资源状况可分为3种类型,分别为过度捕捞已严重衰退的资源、充分利用并开始衰退的资源和尚有潜力的资源,其中大黄鱼、鳓鱼资源已进入资源衰退期,带鱼、鲐鲹鱼类、墨鱼和小黄鱼等处在充分利用并开始衰退期,虾蟹类、鲳鱼、马鲛鱼、鲷科鱼类和海鳗等资源尚有潜力。  相似文献   

6.
虾类是东海区的主要捕捞对象之一。东海区的拖虾渔业以虾类为主要捕捞目标,发展之初对于促进捕捞结构调整、减轻主要经济鱼类的捕捞压力起了重要作用。但是随着该种作业方式生产规模的不断扩大、生产渔船和渔具的大型化,渔获物中经济虾类和兼捕幼虾的矛盾日益突出,对东海区的渔业资源造成较大程度的破环。本文主要介绍了东海区拖虾渔业的发展和资源概况,主要经济虾类的种类、分布、作业渔船的产量和数量变化,分析了东海区拖虾渔业中存在的问题和所采取的措施,并提出了解决问题的建议。  相似文献   

7.
东海区伏季休渔渔业生态效果的分析研究   总被引:38,自引:9,他引:29  
以1990 ~1998 年我国东海区的海洋渔业统计资料和渔业资源动态监测资料为依据,分析研究1995 ~1998 年伏季休渔对东海区渔业生态效果的影响。结果表明,带鱼等主要经济鱼类的产卵群体得到了有效保护;经济幼鱼的渔获比例及其资源密度指数有所提高,幼鱼群体养护效果也较明显;渔获个体的生物学特征值具有转好的趋势;主要经济鱼类资源生物量明显增加;渔业资源的种间结构得到一定程度的改善;年渔获产量明显增加,单位捕捞努力量渔获量(CPUE) 有所提高。  相似文献   

8.
东海区底拖网渔业资源变动分析   总被引:8,自引:2,他引:6  
以2000~2005年底拖网渔业资源的常规监测资料为依据,对东海区底拖网渔获物种类组成、主要经济鱼种单位捕捞努力量渔获量(CPUE)以及生物学特征进行了分析。结果表明,东海区底拖网渔业资源利用结构正在向低值和低营养层次鱼种转化,主要经济鱼种的CPUE不断下降,生物学特征未见明显好转,而渔获物中幼鱼比例不断上升,渔业资源总体状况仍然存在继续衰退趋势。建议降低目前的海洋捕捞努力量,延长伏季休渔时间,加强渔业资源养护和管理力度等。  相似文献   

9.
东海区渔业行政地理位置北起35°05′N南至22°OO′N,西临我国大陆,东至200m等深线,是西北太平洋西部一个较开阔的边缘浅海,大陆架渔场面积约5729k-m’,约占我国海域陆架总面积的3876%Q由于长年受黑潮暖流、大陆架沿岸流的混合交替作用,东海区陆架渔场一直是我国沿海资源蕴藏量最丰富的海域。渔业资源品种繁多,计有鱼类近7O0种、虾蟹类15O多种、头足类6O多种,其中主要经济渔业资源鱼类有19种、头足类2种、虾蟹类13种、水母1种,1998年海洋捕捞产量约占全国海洋捕捞量的42%。针对渔业资源繁多的特点,东海区的作业方式也是多…  相似文献   

10.
为深入贯彻落实科学发展观,推动全国海洋捕捞信息采集网络工作制度和信息分析新机制的建立,进一步增强科研对渔业管理的技术支撑作用,根据农业部渔业局的部署,东海区渔政局最近在上海组织召开了“海洋捕捞信息动态采集”工作会议。东海区渔业资源动态监测网络成员单位的站长及技术骨干参加了会议,东海区局钟小金副局长到会指导。  相似文献   

11.
This paper describes a computer program for the analysis of catch returns from put-and-take fisheries that can be operated by personnel with minimal computer training. The program was developed for the Toft Newton fishery in Lincolnshire and the method of collecting the data is illustrated. The advantages of using computer analysis for assessing the state of a fishery are outlined. A completed listing of the program can be obtained from the authors.  相似文献   

12.
王东  甘绪兰 《淡水渔业》1993,23(2):11-13
本文介绍了MSED系统(the Modeling System of Experimental Data in Biology)的功能及其在水产科学中的应用。该系统能完成由其自身提供的20个函数组合生成的数以万计的数学模型的回归分析,是一强有力的、实用的、集成化的水产实验数据处理软件工具。  相似文献   

13.
An important element in the U.S. management of fisheries in the North Pacific is the existence of Community Development Quotas (CDQs) which grant community corporations the right to fish in many fisheries off the coast of Alaska. The eastern Bering Sea pollock fishery is the largest of these fisheries, with 10 % of the quota allocated to CDQs. The CDQ program evolved from a partial catch share program that existed from 1992 to 1999 within a limited-entry fishery to a full catch share program with separate spatial rights. In this paper I examine the temporal and spatial uses of CDQ rights and how these uses have changed since the implementation of catch shares throughout the fishery. I also discuss the dispersion of CDQ royalties since the program’s inception and examine the prices of CDQ fishing rights from 1992 to 2005 when data on quota value were reported to the government. I compare quota prices to information about walleye pollock fishing and examine the evolving use of CDQ rights. The use of the CDQ right has changed from extending the season to enabling fishing in otherwise closed areas during the season. The number of vessels fishing with CDQ rights has declined substantially, with all pollock CDQ fishing now done by at-sea processors.  相似文献   

14.
Abstract. A non-linear programming model was developed to determine the benefits obtainable from the inland capture fisheries of Bangladesh. Functions and parameters of a base model were estimated by deriving non-linear catch-effort and cost functions as well as rice responsive demand functions using both primary and secondary data. Results of LP (linear programming) solution of the base model suggest that the inland fisheries of Bangladesh are capable, under optimal conditions, of generating a total net benefit of Bangladesh Taka (BDT) 1383 million per annum (US$1 = BDT38), most of which (96%) accrues as producer surplus. Under the optimal allocation of total fishing effort the model shows a 13% reduction in overall fish catch with 54% less effort. Sensitivity analysis, through variations of fishing effort, shows that the incorporated variables (e.g. catch, cost, benefit and shadow price) change in line with theoretical expectations. The implication of these results for management is that a reduction in effort would be required in order to generate a greater net economic benefit from the riverine fisheries. Such reduction should be specific to individual fishery and/or fishing grounds.  相似文献   

15.
以全球定位系统(GPS)、地理信息系统(GIS)和遥感(RS)等3S技术集成平台,并结合船舶监控系统(VMS)、北斗卫星短报文信道、ARM高性能处理器、NR嵌入式操作系统等前沿技术,建立"南海渔业信息动态采集与实时自动分析系统"。该系统是一个分布式系统,包括船载捕捞信息实时采集装备、南海渔业数据集成中心、南海渔业捕捞地理信息系统及外海渔场预报系统等4个完全独立分布的子系统。本系统自主研发了具备北斗通信功能的船载捕捞实时采集装备,并创新性地利用北斗卫星短报文信道实现了海上渔船与地面数据中心的实时信息交互,此外利用VPN信道实现了数据中心与数据处理分析应用系统之间安全可靠的数据共享,从而最终建立了海上渔船与岸上数据分析系统之间的无缝连接虚拟网络。基于这一网络,海上渔船将渔业捕捞数据实时发送至南海渔业捕捞GIS系统,进行实时分析与显示海洋捕捞(分)渔区/渔船/鱼类产量的数据分析专题图;外海渔场预报系统依据多年的捕捞、渔业生物学及渔场环境数据收集与分析将南海外海鸢乌贼渔场信息发送给海上渔船,推进海上渔业捕捞的高效生产。  相似文献   

16.
Developing robust frequentist and Bayesian fish stock assessment methods   总被引:1,自引:0,他引:1  
Errors in fitting models to data are usually assumed to follow a normal (or log normal) distribution in fisheries. This assumption is usually used in formulating likelihood functions often required in frequentist and Bayesian stock assessment modelling. Fisheries data are commonly subject to atypical errors, resulting in outliers in stock assessment modelling. Because most stock assessment models are nonlinear and contain multiple variables, it is difficult, if not impossible, to identify outliers by plotting fisheries data alone. Commonly used normal distribution‐based frequentist and Bayesian stock assessment methods are sensitive to outliers, resulting in biased estimates of model parameters that are vital in defining the dynamics of fish stocks and evaluating alternative strategies for fisheries management. Because of the high likelihood of having outliers in fisheries data, frequentist or Bayesian methods robust to outliers are more desirable in fisheries stock assessment. This study reviews three approaches that can be used to develop robust frequentist or Bayesian stock assessment methods. Using simulated fisheries as examples, we demonstrate how these approaches can be used to develop the frequentist and Bayesian stock assessment approaches that are robust to outliers in fisheries data and compare the robust approaches with the commonly used normal distribution‐based approach. The proposed robust approaches provide alternative ways to developing frequentist or Bayesian stock assessment methods.  相似文献   

17.
针对当前我国渔业发展现状,提出吸引和利用外商直接投资(FDI)渔业来实现渔业增长方式的转变。通过分析我国渔业利用外资的现状及存在的问题,从扩大利用外资规模、提高利用外资质量等方面提出了相应对策。  相似文献   

18.
海洋渔业电子地图系统软件设计与实现   总被引:2,自引:0,他引:2       下载免费PDF全文
邵全琴 《水产学报》2001,25(4):367-372
系统地介绍了海洋渔业电子地图系统软件EA2000的数据模型和主要功能的设计与实现,EA2000采用了面向对象的数据模型,紧密的矢栅数据接口,以及图层-地图-图集一体化数据组织管理方法,该软件具有开放的数据输入接口,图层创作的自动化和动态交互式编辑,双向查询检索,缩放漫游与多级比例尺联动显示,动态显示,对象信息自动显示,地理信息系统渔船动态监控管理,多媒体信息插入管理,互操作等功能。  相似文献   

19.
改革开放以来,随着渔业经济的快速发展,我国的渔业发展面一临着渔业资源严重枯竭、渔业监管困难、渔民收入增长幅度放缓等诸多问题。为此学术界在渔业资源管理方法上提出了许多意见,同时也存在着一些分歧。文章通过理论推演,结合文献数据,探讨了渔村社区组织与我国渔业协会的关系,分析了包括渔业协会在内的渔村社区组织对渔业资源管理的作用,通过对代表性渔业资源管理理论的利弊分析,剖析了渔民协会等渔村社区组织的渔业资源管理职能。同时指出由于渔业协会在资源管理中具有重要作用,但因其自身也存在着一定局限性,因此,培育渔业协会、完善其资源管理职能,实行基于渔业协会等渔村社区组织的合作管理也就成为我国加强渔业资源管理的一种制度选择。  相似文献   

20.
Fisheries policies often pursue multiple objectives, which may, in some instances, be in conflict or competition with each other. It may not be possible, for example, to create or maintain employment and generate increasing volumes of revenue for government whilst also sustaining stocks and biodiversity. Two approaches to fisheries management, one focused on capturing wealth and limiting access and the other on maintaining access for employment and providing community development and welfare, present contrasting policy advice, with different points of emphases and objectives. This article examines the case of Lake Victoria, where the three main commercial fisheries are seen to contribute to different objectives for the lake's fisheries. Insights from the debate between wealth‐based and welfare‐based approaches to fisheries management provide a framework for the analysis of fisheries policy and practice on the lake. From the analysis, it is concluded that whilst there is much rhetoric in support of a wealth‐based approach, this has not been followed through in implementation, reflecting the lack of political support for new taxation and limiting access. The welfare functions of the fisheries are significant, but could be substantially strengthened through greater investment in the provision of services to fisheries communities. The approaches are not mutually exclusive, but pursuing wealth‐based management must support livelihoods, employment and development, as well as fisheries management objectives. Without the incorporation of welfare objectives, fisheries policies will not be politically accepted or fully implemented, suggesting the need for a balance between wealth and welfare objectives and measures.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号