象山港蓝点马鲛渔获情况初步研究

根据2007-2008年蓝点马鲛繁殖季节的调查资料,分析了1 053尾蓝点马鲛样品。研究了浙江象山港蓝点马鲛生殖群体的捕捞产量、叉长、体重及它们间的相互关系等,讨论了象山港繁殖场蓝点马鲛的资源状况,提出了资源保护措施。     

泉州市内陆水域水产养殖规划概述

该规划科学地利用内陆水域资源,规范养殖管理,提高养殖水域利用率;合理开发利用养殖水域,有效保护养殖水域生态环境,加快完善和推进养殖管理制度;促进渔区和谐发展,确保渔业增效、渔民增收,确保内陆水域水产养殖业的可持续发展。实施该规划后,力争到2015年全市淡水水产品总产量达2．5万吨以上,比2006年增加6313吨,年均增长3．75％;淡水养殖渔民人均纯收入达10000元以上。     

对印度尼西亚海域中国渔船使用拖网渔具的分析和探讨

本文探讨了中国渔船在印度尼西亚海域使用的拖网渔具,从渔具使用规格、缩结状态和结构等方面进行了分析,指出这类渔具在浅水渔场捕捞带鱼时有良好适应性,但局部配纲不当,网具贴底程度未达到最佳状态。由于网目大,有些局部改革可能导致敏感的负面反应。作者认为,这类网具今后的改革应着眼于提高拖速,以增加对某些优质鱼的兼捕比例。     

Evidence for a depth refuge effect in artisanal coral reef fisheries

Natural refuges can play a fundamental role in protecting species from overexploitation but have not been adequately quantified in the marine environment. We quantified the effect of a depth refuge on all fish species in an artisanal coral reef fishery in Zanzibar, Tanzania by comparing changes in fish species richness and relative abundance with depth at five fished and three unfished reefs across the region. Commercial species richness was depleted by 15.1% at shallow depths in fished reefs, but there was no difference between the reefs deeper than seven metres. Non-commercial species were not affected by fishing or depth. Evidence for similar patterns in fish communities in other countries and depth-limitations to artisanal fishing methods imply this effect is widespread. The depth refuge effect could be sustaining coral reef fisheries and should be taken in to account before implementing policies or subsidies that encourage or allow fisheries to exploit deeper waters.     

A comparison of methods to spatially represent pelagic longline fishing effort in catch and bycatch studies

Bycatch in fisheries has been recognized as a threat to many endangered populations of sea turtles, sea birds and marine mammals. Interactions between pelagic longline fisheries and critically endangered populations of leatherback sea turtles (Dermochelys coriacea) have led to temporary closures of the Hawaiian pelagic longline swordfish fishery and severe bycatch quotas. The negative impact of these events on both the populations of certain endangered species and the economic livelihood of the fishermen has resulted in a strong push from all sides to better understand bycatch events. Typically, analyses of longline catch and bycatch have examined fishing effort summarized over large areas (≥1°). Although aggregation of effort to this level may be necessary to account for uncertainty, confidentiality concerns, or to make comparisons across regions, it specifically limits the researcher's ability to characterize the local oceanographic factors that may drive individual bycatch events. Higher resolution analyses must be undertaken to identify such features. However, for these higher resolution analyses, the methods currently used to spatially represent pelagic longline fishing effort may significantly affect researcher's results. Here, we look at different methods to represent this fishing effort (i.e., points, centroids, polylines and polygons) at various resolutions (2 km to 5°) to better understand which method and spatial resolution are most appropriate. Our results validate the use of point features to represent fishing effort in previous low resolution studies of the Hawaiian pelagic longline fishery by showing that the set point method is suitable for studies with resolutions lower than 15 km. However, at higher resolutions (≤15 km) and in areas with more sparsely distributed fishing, aggregated effort values differed significantly between spatial representation methods. We demonstrate that the use of polygons to describe pelagic longline fishing effort is more representative and necessary for such high resolution analyses.     

论渔船队规模对渔业资源的影响

本文以大黄鱼为例,应用系统动力学的方法再现了大黄鱼资源的兴衰过程,并通过对模型结果行为的讨论,定量地给出了合理的渔船船队增长规模。本文的方法和结论可作为我国今后合理开发与利用其他种类渔业资源时参考。     

The influence of protection and temperature on subtropical reef fish assemblages in Cape Byron Marine Park

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Geographical variations in the trophic structure of the plankton community along a eutrophic–mesotrophic–oligotrophic transect

The geographical variations in trophic structure of the plankton community, as defined by total and relative carbon biomass of phytoplankton (PP), bacteria (BA), heterotrophic nanoflagellates (HNF), microzooplankton (MZ), and herbivorous (HNZ) and carnivorous net-zooplankton (CNZ), were investigated along an inshore–offshore transect from the innermost part of Osaka Bay to the Pacific Ocean off Kii Channel, Japan, in June 1991. Based on physico-chemical properties of the water and topographical features, the transect was divided into three trophic areas, i.e. eutrophic, mesotrophic and oligotrophic ones. The average carbon biomass of the total plankton community was highest (438 mg m⁻³) in the inshore eutrophic area, and declined steeply offshore (141 and 26.6 mg m⁻³ in the mesotrophic and oligotrophic areas, respectively). In the offshore oligotrophic area, the relative biomass of BA to PP and the relative biomass of small heterotrophs (i.e. BA, HNF and MZ) to the total heterotrophs were higher than in the other areas, indicating that the microbial food chain predominated. In the mesotrophic area, the biomass of HNZ (primarily copepods) was conspicuously high, even higher than that of PP, suggesting that the traditional grazing food chain prevailed. Because of this short food chain, a productive fishing ground is formed there. In the eutrophic area, the biomass of HNZ was much smaller relative to the enormous biomass of PP, indicating that a considerable amount of primary production was not utilized directly by the metazoan zooplankton. However, the relative contribution of the small heterotrophs to the total heterotrophs' biomass was higher in this area, as in the oligotrophic area.     

鄱阳湖沿湖渔区养殖鱼类车轮虫病调查初报

对鄱阳湖沿湖渔区 1 1个县进行了调查 ,初步结果为 :镜检出车轮虫 1 2种 ;养殖鱼类对车轮虫的整体感染率依次为草鱼 >鳙鱼 >鲤鱼 >团头鲂 >白鲢 >白鲫 ;一般利用池塘水进行人工繁殖的水花鱼苗 ,其车轮虫感染率为 1 0 %～ 35 % ,利用循环用水或有机物含量较高的水源孵化鱼苗时 ,鱼苗的感染率则成倍提高 ;车轮虫对夏花鱼种的感染率达1 0 0 % ,且主要以大型车轮虫为主。秋片鱼种以上规格的鱼体主要感染小车轮虫。适宜车轮虫繁殖、生长的水温为 1 8～ 30℃ ,车轮虫可诱发某些细菌性鱼病。探讨了车轮虫的综合防治措施 ,包括切断传染源、用生石灰清塘消毒、用 1～2mg/kg硫酸铜与硫酸亚铁混合液 (5∶2 )杀虫等。     

舟山市海洋捕捞渔船主要助航助渔设备的调查

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