共查询到18条相似文献，搜索用时 93 毫秒
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塞拉利昂近海经济虾类数量与分布初步研究 总被引：1，自引：0，他引：1
根据塞拉利昂近海１６条生产船１年（ａ）生产日志资料（１９９５－０７～１９９６－０６）,分析了２种经济虾类［红对虾（Ｐｅｎａｅｕｓｎｏｔｉａｌｉｓ）、大西洋仿对虾（Ｐａｒａｐｅｎａｅｏｐｓｉｓａｔｌａｎｔｉｃａ）］的产量分布,指出红对虾主要分布于以２区,４４区,８５区为中心的３个渔场,主要虾汛时间为６～８月,大西洋仿对虾主要分布于８４区,９６区,９７区,主要虾汛时间为１１月。同时,还对２种虾类的月平均单船产量进行了比较分析。 相似文献
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塞拉利昂近海两种经济鱼类数量与分布的初步研究 总被引：1，自引：0，他引：1
根据塞拉利昂近海16条生产船一年的生产日志资料(1995．7－1996．6),分析了两种经济鱼类[洛戈舌鳎(CynoglossusCanariensis)拟牙(Pseudotolithus)]的产量分布,指出洛戈舌鳎跟主要分布于以3区,44区,97区为中心的三个渔场,但产量较低,仅作为兼捕对象。拟牙线主要分布于44区,84区,97区,主要渔汛时间为9～11月。同时,还对二种鱼类的月平均单船产量进行了比较分析。 相似文献
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美国是世界海洋经济主要国家,主要海洋产业有近海油气业、海运业及海上工程服务业和海洋生物技术产业等高附加值海洋产业等。据估计,1995年美国海洋产业产值占国民生产总值(GDP)的4％～5％。然而,美国海洋产业,特别是高新技术产业在实现产业化规模经营方 相似文献
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江苏近海紫菜养殖区的空间扩张模式研究 总被引：1，自引：0，他引：1
为精准实施海域使用现状的动态监测与有效管理,开展了江苏近海紫菜养殖区空间扩张模式研究。选取1990年、2000年、2013年和2018年四个时相的Landsat遥感影像为数据源,采用面向对象分类方法提取江苏近海紫菜养殖区的空间分布信息,分别计算1990年、2000年、2013年和2018年江苏近海紫菜区养殖面积并分析其变化趋势,揭示江苏近海紫菜养殖区空间分布特征,并剖析江苏近海紫菜养殖区的空间扩张模式。研究结果表明:(1) 1990年、2000年、2013年和2018年,江苏近海紫菜养殖区分布面积分别为804.69 hm~2、6 097.95 hm~2、29 453.29 hm~2、42 316.98 hm~2,呈现逐年增加的变化趋势。(2)江苏近海紫菜养殖区主要分布在连云港海域以及盐城-南通交界海域。(3)基于2018年紫菜养殖区空间分布格局,在江苏近海的部分港口航运区和特殊利用区存在紫菜养殖的不合理用海行为。(4)连云港海域紫菜养殖扩张模式以密度增大的填充型为主,盐城-南通交界海域以密度增大的外延型为主。该研究可为相关海洋管理部门提供江苏近海紫菜养殖区空间分布和扩张模式的基础数据,也可为控制江苏近海紫菜养殖规模,优化海洋产业布局提供决策支持。 相似文献
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为了科学有效地掌握海域使用信息、管理海域权属,为海域资源调查、管理、规划、保护、合理利用提供服务,为违法、违规、违章用海项目得到有效遏制,减少用海矛盾,有必要开展海域使用动态监测,作者以连云港近海为研究区,利用4个时相Landsat遥感影像(2002、2008、2013、2016年)通过面向对象算法提取弱水背景下的紫菜养殖区信息,揭示空间分异规律,并分析其驱动原因。研究结果表明:4期影像提取连云港近海紫菜养殖区信息的精度分别是87.5%、92%、91.7%和94.6%。紫菜养殖区空间分布的变化规律为紫菜养殖面积不断增加且整体向深海方向推进。赣榆港口航运区和田湾核电站特殊利用区存在少量紫菜养殖区,项目用海不符合连云港市海洋功能区划(2016～2020年)。连云港近海紫菜养殖区空间分异的驱动因子主要是自然条件、养殖技术、海洋经济和社会发展四大因素。 相似文献
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中西太平洋金枪鱼围网高产渔区年间变化及其原因分析 总被引：1，自引：1，他引：0
金枪鱼类是中西太平洋海域重要的经济鱼种,其中鲣产量约占到总产量的50%。本研究利用1995-2010年16年的中西太平洋（20°S~20°N,120°E~155°W）鲣围网生产统计数据和Niño3.4海区（5°S~5°N,120°~170°W）海表温度异常数据,对这16年鲣产量最高的十大渔区（5°×5°）进行时空格局分析,讨论渔场分布差异及CPUE与ENSO指数的关系。结果表明:16年间十大作业渔区主要分布在5°S~5°N、130°~175°E区域,这十大渔区产量占总产量的比重达47.5%,其中5°S~0°、155°~160°E,0°~5°N、130°~135°E,0°~5°N、135°~140°E及5°S~0°、160°~165°E等4个渔区产量占高产渔区产量的比重均超过10%,是中西太平洋重要的鲣产区。高产渔区的分布受海表温度影响较大,在厄尔尼诺时期,高产渔区分布明显偏东,主要分布在155°~180°E海域;在拉尼娜时期,高产渔区分布明显偏西,主要分布在130°~160°E海域。 相似文献
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1997年,福建省主要渔区之一的惠安县崇武镇掀起开发海洋水产业热潮,重振了水产强镇雄风。全镇渔业总产量7.49万吨,产值3.89亿元,分别比增12.9％和36.56％。被省政府列为“渔业十强镇”。 相似文献
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为探明舟山近海海域仔稚鱼丰度的分布、出现概率及与环境因素的综合关系,进一步研究该海域渔业资源的补充机制,根据2019年3、4、7、11月在舟山近海海域开展的4个航次仔稚鱼生态调查资料,研究了舟山近海仔稚鱼的出现概率、群落结构(种类组成及优势种数量)的动态变化,探讨仔稚鱼群落的季节变化和对环境变化的响应,以及环境变化对仔稚鱼补充量的影响。结果显示:空间上,调查海区水深范围5～50 m,仔稚鱼集中分布于水深10～20m的近岸河口岛礁区;时间上的季节变化比较大,春夏季丰度高,冬季少。GLM模型结果显示:近岸河口型仔稚鱼在近岸出现的概率为0.65～0.95,在近海出现的概率为0.26～0.60;近海型仔稚鱼在近岸出现的概率为0.12～0.34,在近海出现的概率为0.32～0.54。仔稚鱼优势种春夏季各出现1种,秋冬季各出现2种,全年仔稚鱼优势种有4种。数量分布为:仔稚鱼种类数春季(19种)、夏季(16种)、秋季(10种)、冬季(5种),具有明显的季节性变化。按种类适温属性划分,调查海区仅出现暖温性和暖水性两种,其中暖温性15种(占已知适温类型种类的60%),暖水性10种(占40%);按生态类型... 相似文献
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基于分类回归树算法的东南太平洋智利竹筴鱼渔场预报 总被引：4，自引：0，他引：4
为了提高智利竹筴鱼渔场预报水平和满足渔业捕捞生产的需要,利用2002—2008年的东南太平洋公海海域捕捞的中国大型拖网渔船共计15艘的生产统计资料,以及海洋环境数据(包括海表温度、叶绿素a浓度、表温距平、叶绿素a浓度距平、海表温度梯度强度和海面高度异常等数据),基于CART的算法,构建了智利竹筴鱼渔场决策树预报模型。用含1 114条记录的数据集对模型进行训练,并采用ROC方法对该模型诊断中心渔场的准确性进行了分析。最后将该模型应用于2009年各月份的智利竹筴鱼中心渔场预报,并与实际渔场位置进行了对比,结果显示预报渔场与实际生产位置基本一致,表明利用CART决策树方法建立智利竹筴鱼渔场预报模型是可行的。 相似文献
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The actual or potential effects on fishing health and safety of the full scope of national and international regulatory regime components governing commercial fishing are often poorly understood. Especially lacking are comprehensive reviews of all the government policies that directly and indirectly affect fishing risk within countries with significant commercial fisheries. We present the results of a comprehensive, multi-national project that compares the regulatory regimes of six countries (Canada, US, UK, Iceland, New Zealand, and South Africa) and examines the impacts (either real or perceived) of legislation and regulations on fishing occupational health and safety outcomes. A conceptual model is proposed that identifies potential sources of direct and indirect risks to fishing health and safety in order to throw light on potential pathways from regulation to fishing safety. Our results highlight differences and gaps in the regulatory frameworks of the countries studied and point to the urgent need for improved assessment and for access to accurate and standardized statistics regarding fishing-related injuries and illnesses. We conclude with several recommendations for moving forward. 相似文献
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渔村治理现代化作为实现乡村振兴战略的重要组成部分,因其自身固有的发展特征,亟须进行法治化改革。这既是对全面依法治国方略在渔村治理的落实,也同新时代乡村治理体系的基本逻辑相符合。因此,新时代法治渔村建设需要中国特色社会主义法治价值的指引,法治价值同时为推进新时代渔村治理法治化,为渔村的政治、经济、社会发展以及生态文明建设等提供了重要的思想基础。法治价值的适用同样对于促进渔村渔业的高质量发展和改善传统渔村经济落后的局面具有重要意义,有必要在中国特色社会主义法治价值的指引下,找到新时代渔村良法善治的有效路径。 相似文献
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《Marine Policy》2014
Fisheries management systems based on Transferable Fishing Concessions (TFC) and similar rights-based systems have been developed during the last decades in some European countries. However, at present there is not a clear view on the possible effects caused by the application of this management systems in the Mediterranean Sea. The current study, involving nine Geographical Sub-Areas (GSAs) of the Mediterranean Sea, focuses on the appropriateness, transferability and modes of applicability of a TFC system in the Mediterranean area. Three different scenarios of quota allocation have been analyzed by taking into account biological, ecological, environmental, economic and social aspects: quota in terms of resource quantity, quota as a portion of the total fishing time, quota as a portion of the total fishing capacity. Results show that the transferability of a TFC-based system to the Mediterranean context appears to be low due to the characteristics of the Mediterranean fisheries (multispecificity of resources, fishing grounds shared among different countries, multigear, importance of small-scale fisheries) and to the general lack of sound and reliable individual historical data. The study also highlights rights-based systems such as Territorial Use Rights in Fisheries (TURF) might only be applied for the exploitation of sedentary resources, such as clams. A management system based on TFC could be theoretically reasonable for anchovy fishing, where a few species are caught, even if all countries and stakeholders should be involved in the decision making process. 相似文献
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《African Journal of Marine Science》2013,35(1):257-263
The mean effective fishing area (EFA) of a Japanese-type crab trap fishing for Geryon maritae on the northern South West African red-crab grounds was calibrated as 2 160 m2. The commercial fishery uses traps covered with 90-mm mesh. In order to be able to use the density results obtained by this survey from traps covered with 60-mm mesh, a preliminary mesh selectivity study was carried out. The carapace width at 50-per-cent retention for 90-mm mesh was estimated as 72 mm. Based on the EFA results, it seems that most commercial fishing takes place in areas of crab density varying between 46 and 231 crabs·ha?1, but that densities can reach ～510 crabs·ha?1. It is suggested that crab traps would fish more efficiently on the northern South West African crab grounds if longlines were set across the depth contours rather than in a longshore direction. 相似文献
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Oceanographic Characteristics of a Multi-Specific Fishing Ground of the Central South Brazil Bight 总被引：1，自引：0，他引：1
In the Central South Brazil Bight, a multispecific demersal trawl fishery is conducted by trawlers licensed for the industrial pink shrimp (Penaeus paulensis and Penaeus brasiliensis) fishery. In addition to the pink shrimp, many by-catch species have become increasingly valued in the last two decades. In spite of the importance of this multispecific fishery, the oceanographic characteristics of the inner continental shelf, onshore the 100 m isobath, are poorly known. In this paper we present, for the fist time, monthly oceanographic records taken from December 1995 to May 1997 with the R/V ‘Diadorim’ at two of the main fishing grounds of this region. Water temperature data showed the formation of a strong thermocline during summer, from November to April. This thermal gradient, due to the South Atlantic central water (SACW) intrusion that reaches these shallow waters, disappeared with the homogenization of the water column during autumn and winter, from May to September. This cold and low salinity water does not originate from local river discharges, but also represents an advection of sub-Antartic water mass. After this and during spring, a new thermocline develops, reaching its maximal expression from February to March. A maximal gradient was registered in February 1997, when the temperature dropped from 26°C at 7 m to 16°C at 14 m depth. This result shows that the SACW intrusion is a large-scale phenomenon that regularly influences the whole inner continental shelf up to 20 m. Demersal fishing grounds located in this area were covered during summer by a cold and nutrient-rich mass of water that resulted in an unusual maximum of chlorophyll a values near the bottom (30 m). The homogenization of the water column and the presence of another cold water mass during winter resulted in a strong semi-annual thermal cycle on the bottom. The role of this important oceanographic process in fishery production and dynamics deserves further investigation, but the data presented here show evidence for the importance of this phenomenon. 相似文献
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Managing marine fisheries using output controls in the form of individual transferable quotas (ITQs) can be an attractive alternative to more traditional input controls. There are now a number of examples of where ITQ-managed fisheries have been able to reduce the impact of the major management problems in global fisheries, namely, gross over-capitalisation and effort. However, ITQs are not the perfect management tool and one of the lesser known consequences of ITQ-managed fisheries where ITQs consist of a harvest right is the implicit relationship between ITQ property rights and rights of access to the fishing grounds. This implicit spatial right to the grounds can provide obstacles in the way of allocating water-space within fishing grounds for alternative uses such as marine-protected areas, large-scale aquaculture, and wind farms. These lesser-known consequences of ITQ-managed fisheries are discussed here. 相似文献