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1.
基于统计数据的中国海洋渔业资源利用状况及管理分析 总被引：5，自引：1，他引：4
本文根据1987年~2006年捕捞统计数据,对我国海洋渔业资源利用状况进行了分析,讨论了相关管理政策及措施。结果表明：①1999年以来,我国海洋捕捞总产量结束了长期持续快速的增长,出现下降并趋于稳定,渔获物大类构成趋向稳定,主要鱼类渔获物结构趋向均化;②海洋捕捞机动渔船数量在1997年之后趋于稳定,专业劳动力数量1998年以来保持下降趋势,总主机功率和总吨位20年来一直保持增长,渔船结构趋向大型化;③海洋机动捕捞渔船单位主机功率CPUE和单位吨位CPUE在1998年以来持续下降,单船CPUE和捕捞专业劳动力人均CPUE在1998年以后趋于稳定。讨论分析认为：①我国海洋渔业资源整体处于充分利用状态,捕捞能力总体过剩;②我国目前的捕捞投入控制不能有效控制实际捕捞能力,建议在渔船数量控制基础上,引入渔具类型、数量和规格等渔具限制制度;③需改进现行捕捞统计制度。 相似文献
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“棒打狍子,瓢舀鱼。”这句话形象地概括了当年人烟稀少而生物资源丰富的北大荒。与野生动物资源一样,自然水域资源也经历了一个由物产丰富到趋于枯竭的过程。据有关资料显示,黑龙江省境内有松花江、黑龙江、乌苏里江、嫩江、牡丹江、呼兰河、兴凯湖等重要的渔业水域。资源丰富,重要的经济、特产鱼类品种繁多。上个世纪六十年代编写的《黑龙江鱼类志》中记载的冷水性鱼类是一百多种,后经过详细调查确定为95种。但现在,分布量很少,一些珍惜鱼种在部分流域、江段已经绝迹。这里仅介绍几种珍稀冷水鱼类的生存现状。 相似文献
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“棒打狍子,瓢舀鱼。”这句话形象地概括了当年人烟稀少而生物资源丰富的北大荒。与野生动物资源一样,自然水域资源也经历了一个由物产丰富到趋于枯竭的过程。据有关资料显示,黑龙江省境内有松花江、黑龙江、乌苏里江、嫩江、牡丹江、呼兰河、兴凯湖等重要的渔业水域。资源丰富,重要的经济、特产鱼类品种繁多。上个世纪六十年代编写的《黑龙江鱼类志》中记载的冷水性鱼类是一百多种,后经过详细调查确定为95种。但现在,分布量很少,一些珍惜鱼种在部分流域、江段已经绝迹。这里仅介绍几种珍稀冷水鱼类的生存现状。 相似文献
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中华鲟,又称鳇鲟、黄鲟、着甲、腊子、覃龙、鳇鱼、鲟鲨等,属硬骨鱼类鲟形目,主要生活在我国近海及长江流域,是一种大型的溯河洄游性鱼类,世界现存鱼类中最原始的种类之一。远在公元前1千多年的周代,就把中华鲟称为王鲔鱼。鲟类是一个大家族,在 相似文献
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本文研究的主要水域,包括嫩江干流丹岱至河口江段及其右岸附属水域和第二松花江干流前郭、扶余江段及其附属水域(以下简称为两江水域)。该水域天然鱼类资源十分丰富,渔业生产发达,是黑龙江流域淡水鱼最重要的集中产区之一,其中吉林省部分历年天然捕捞量占全省同类产量的70—80％。 嫩江干流下游江段历年捕捞量占整个嫩江流域的65％—75％,最高年份达83％;第二松 相似文献
6.
多准则渔业管理政策优选研究——以东海为例 总被引：1，自引：0，他引：1
本研究在已建立的东海EwE模型基础上,采用EwE中的"渔业政策优选"模块,根据东海渔业资源开发利用现状,模拟系统在经济、社会和生态三重准则下对多种渔业管理政策的响应,并结合层次分析法(AHP)从政策方案中选出"最理想的"东海渔业政策架构.模拟的时间尺度为41年,备选方案包括3个单准则方案、1个多准则方案和31个"复合准则方案".结果表明:单准则方案和多准则方案将导致各种渔具捕捞努力量发生较大变化.35个方案间的比较分析结果为基于生态系统的东海渔业管理(EBFM)和海洋捕捞作业结构调整提供了一些有益的思路:①单一准则的渔业管理策略和具有相同优先级的多准则渔业管理策略不能实现EBFM总体目标;②就东海目前的渔业经济和社会状况而言,不宜过分地抬高生态系统准则在渔业管理中的地位,经济和社会准则仍然重要:③东海海洋捕捞作业结构调整的总体思路应该是减少拖网和虾拖网作业、控制围网和流刺网作业、大力发展外海渔业. 相似文献
7.
青海省野生经济鱼类资源现状和面临的危机 总被引：3，自引：0，他引：3
对青海省10种主要经济鱼类资源状况及环境的调查显示,人类活动和环境改变对鱼类资源产生了较大影响。本文通过1997～2004年在青海湖、黄河上游和柴达木盆地的调查,对青海省野生经济鱼类资源变化状况及其产生原因进行了分析。调查中,主要经济鱼种在捕获物中均有发现,但鱼种类组成及种群结构和数量皆有明显变化,鱼类多样性已遭到明显破坏,群体数量减少,个体趋于小型,其中,黄河的厚唇裸重唇鱼、骨唇黄河鱼、柴达木盆地花斑裸鲤和甘子河裸鲤亚种已处于极度濒危,克鲁克湖的青海湖裸鲤种群有可能面临灭绝。青海省野生经济鱼类资源的衰退是多种因素造成的,其中过度捕捞和非法渔业是主要威胁。最后提出了青海省野生经济鱼类科学保护和持续利用的对策。 相似文献
8.
我国渔业资源养护与管理的基本法律制度初步形成于20世纪80年代后半期,90年代中期以来有所调整和加强,在基本立法上已经形成了较为完整的制度体系,并在渔船削减和禁渔措施方面取得了一定的成效,但仍存在法制不完善、现有制度未能全面执行的问题:①《渔业法》配套行政立法滞后;②部分已经实行的养护和管理措施尚未有立法予以规范;③现有的渔具限制、幼鱼保护等措施未能得到有效执行;④捕捞产出控制和渔业资源分配制度缺失,仍主要依靠捕捞投入控制和技术管理措施;⑤捕捞准入制度、捕捞统计管理制度等重要的基本制度缺乏。我国渔业资源养护与管理的法制建设,既需要加强现有制度的实施性立法,也要注重基础管理制度的完善,更为重要的是加强执行。建议:①严格执行现有较为完整的管理制度,特别是渔具数量、规格限制管理和幼鱼保护技术措施,并加强《渔业法》配套立法,提高《渔业法》的可执行性;②加强基础制度建设,特别是捕捞统计数据监督与核实制度、适合我国国情的渔业资源分配制度。 相似文献
9.
通过1998年至2000年间舟山群岛地区鱼类栖息地环境、渔业劳动力和管理措施、渔获物产量和产值等生态、社会和经济综合参数的海岸剖面分析模型(CTAM)的构建,实现该地区渔业资源变化以及渔获物、现金和劳动力流通的可视化,初步评价近海、外海大小型渔业的经济-社会-生态综合效益,为东海海洋渔业的可持续发展提供有价值的信息和建议.分析结果表明:①渔业资源的保护和增长可通过鱼类栖息地的保护和渔具类型与规模的控制实现;②舟山地区可加强海洋捕捞业的竞争力,拓展国内外市场;③科学发展舟山群岛渔业需要严格控制近海渔业,做好近海小型渔业转产转业工作,并适当发展外海渔业,同时做好近外海渔业资源的保护工作. 相似文献
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A research group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol-a chemical found in the skins of red grapes in red wine-can improve the sensitivity of mice to the hormone insulin according to a report in the October issue of Cell Metabolism.…… 《中国科学院院刊(英文版)》2008,22(1):14-15
Aresearch group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol--a chemical found in the skins of red grapes and in red wine--can improve the sensitivity of mice to the hormone insulin, according to a report in the October,2007 issue of Cell Metabolism. As insulin resistance is often characterized as the most critical factor contributing to the development of Type 2 diabetes, the findings“provide a potential new therapeutic approach for preventing or treating” both conditions, the researchers said. 相似文献
12.
《中国科学院院刊(英文版)》2008,22(1):2-3
CAS should stick to the principle of rendering service to, and giving impetus for, the development of China＇s science enterprise by making S＆T innovations, said CAS President LU Yongxiang. The CAS president made the remarks in a recent talk to communicate the gist of the winter session of the Party＇s Leading-member Group at CAS, which was held from 7 to 11 January in Beijing. 相似文献
13.
Marjorie Armstrong-Stassen Margaret Landstrom Ramona Lumpkin 《The Information Society》1998,14(2):153-164
This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors. 相似文献
14.
《中国科学院院刊(英文版)》2008,22(1)
With great care, Dr. ZHOU Zhonghe takes out a package wrapped by cotton tissue from a drawer and says: "This is the gem of our collections: the fossil of a bird that lived 125 million years ago!" Then, pointing at a tiny mound, he explains: "Look, this is the claw and that is the head. It was in the egg shell and ready to hatch ... The species fell into a family of waterside inhabitants." 相似文献
15.
A joint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology his co-workers from Norway US Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells suggesting that China's projected climate warming could decrease the pest's numbers. The study was published in Proceedings of the National Academy of Sciences on September .…… 《中国科学院院刊(英文版)》2008,22(1):6-7
Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China＇s projected climate warming could decrease the pest＇s numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007. 相似文献
16.
Caroline Haythornthwaite 《The Information Society》2001,17(3):211-226
A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction. 相似文献
17.
Active biological molecules functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery disease diagnosis therapy new nanodevice construction.…… 《中国科学院院刊(英文版)》2008,22(1):22-22
Active biological molecules and functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery, disease diagnosis and therapy, and new nanodevice construction. 相似文献
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Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies. 相似文献
19.
Leah A. Lievrouw 《The Information Society》2000,16(2):155-159
This essay focuses on universal service and the Internet as means to support social and political participation. The emphasis on access to telecommunications systems in conventional approaches to universal service is contrasted with access to content. A model of the information environment is described that accounts for the roles of content and conduit, both of which are necessary conditions to achieve true access. A method is outlined for employing information indicators to observe or measure the information environment. 相似文献
20.
Puay Tang 《The Information Society》1998,14(1):19-31
The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means. 相似文献