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南海北部海域小型非经济鱼类资源声学评估 总被引:14,自引:0,他引:14
为探讨南海北部渔业资源的可持续利用情况 ,根据 1997年 12月~ 1999年 6月“北斗”号调查船SimradEK5 0 0回声探测 积分系统在南海北部海域获取的渔业资源调查资料 ,对该海域天竺鲷科、科、灯笼鱼科、鳄齿鱼科以及犀鳕科等 5类 5 8种小型非经济鱼类进行了资源量评估。结果表明 ,这些种类在南海北部海域具有比较丰富的资源储量 ,它们春、夏、秋、冬 4个季节的平均资源量分别为 18.5× 10 4t,2 6.1× 10 4t,2 2 .3× 10 4t,17.6× 10 4t和 4.5× 10 4t ;分析了其资源量的区域分布和季节变化。 相似文献
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With the decline of fish stocks, the proportions of economically important invertebrates like crustaceans and cephalopods have increased in the Bohai Sea. The community structure and trophic level of economically important invertebrates were analyzed using the bottom trawl survey data collected by the Yellow Sea Fisheries Research Institute in the Bohai Sea in May and August of 1958–1959, 1982, 1992–1993, 2004, 2009 and 2015. A total of 37 species of economically important invertebrates, belonging to 5 orders, 24 families, were captured. The biomass densities of economically important invertebrates in the Bohai Sea displayed an overall downward trend from 1982 to 2015. Oratosquilla oratoria and Loligo spp. were the most dominant species in the past 30 years, the biomass proportion of O. oratoria increased gradually in both May and August from 1982 to 2015. Moreover,biodiversity indices of economically important invertebrates in the Bohai Sea appeared to decline from 1982 to2004 and then increased in 2015. Similarly, the mean trophic level of economically important invertebrates declined from 1982 to 2004 and increased slightly in 2015. Overall, although the proportions of invertebrates have increased, the biomass densities in the Bohai Sea have displayed an overall downward trend from 1982 to 2015.The increases in the biodiversity and trophic level of economically important invertebrates after the 2000 s,possibly benefit from stock enhancement projects implemented by governments at different levels and national fishery management measures such as the "double-control" of the total number and engine power of fishing vessels and summer moratorium of fishing. 相似文献
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China(herein referred as China’s mainland,and excluding Hong Kong,Macao and Taiwan)ranks as the world’s leading fishing nation,with approximately 11.1 million tons of domestic marine catch acquired in 2017.Marine fisheries resources in China are mainly exploited by its 11 coastal provinces and municipalities,and the development of fishing industry varies among them.However,few studies have examined the exploitation history of the 11 coastal provinces and municipalities.In this paper,we systematically quantified the exploitation history of marine fishery resources in China and then measured the vulnerability of the 11 coastal provinces and municipalities of China to a reduction in marine catches.Our analysis suggested that Chinese marine fisheries experienced rapid growth from the mid-1980 s to the end of the 20 th century,and this rapid increase in marine catches were mainly promoted by increased fishing effort.The total primary production required level amounted to approximately 80%of the average primary productivity in 2017,and Zhejiang,Fujian,Shandong,Hainan and Guangdong provinces were the main fishing provinces in China.By assessing three dimensions of vulnerability(exposure,sensitivity and adaptive capacity)to the impacts of a reduction in marine catches in the 11 coastal provinces and municipalities,we found that Hainan,Guangxi,Zhejiang and Fujian provinces had high or very high vulnerability,while the municipalities of Shanghai and Tianjin had low vulnerability.Identifying suitable adaptation policies and management plans based on the differences in vulnerability among coastal provinces is important in sustainable fisheries management. 相似文献
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Changes in fish diversity and community structure in the central and southern Yellow Sea from 2003 to 2015 总被引:1,自引:0,他引:1
The central and southern Yellow Sea is an important overwintering ground for many fish species in the Bohai Sea and Yellow Sea. For better understanding the status of the fish community after years of heavy exploitation, variations in fish community structure and diversity were analyzed using data from bottom trawls during 2003–2015. Five fish assemblage indices all showed fluctuations without clear trends from 2003 to 2015, yet there were strong positive and significant correlations(P 0.05) among them. The top-five dominant species accounted for a high weight percentage(49.7%–82.1%) in the annual fish catch. Multivariate analysis showed that two year groups could be pooled for the fish community: Group Ⅰ consisted of the years 2006, 2007, 2008 and 2015, while Group Ⅱ consisted of the years 2003, 2004, 2005, 2009, 2010 and 2014; the groups aggregated with 63.71% similarity, indicating a high level of similarity among all years. The multivariate dispersion values were 1.455 and 0.818 for Groups Ⅰ and Ⅱ, respectively, indicating greater variances in fish assemblage structure in Group Ⅰ than that in Group Ⅱ. Similarity of percentage analysis demonstrated that the average similarities for Group Ⅰ and Group Ⅱ were 71.58% and 67.51%, respectively. Size-spectra analysis revealed no consistent trend in the intercept and slope( P 0.05); there were also no significant differences between the slope of the size-spectra and fishing ef fort. The catch per unit ef fort and mean individual weight analyses of the whole fish assemblage both showed a significantly decreasing trend over time. Overall, the results showed that the fish community structure in the central and southern Yellow Sea was relatively stable from 2003 to 2015 and the study could be used as a reference for supporting ecosystem-based fishery management. 相似文献
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We evaluated the feeding ecology of largehead hairtail (Trichiurus lepturus) and hairtail (T. margarites). We collected specimens from fishing ports in the Beibu Gulf (Gulf of Tonkin) from October 2008 to September 2009 and analyzed their gut contents. We collected 857 T. lepturus and 666 T. margarites samples. The number of stomachs examined in this study was sufficient to describe the monthly and ontogenetic diet shifts for the two species, as indicated by the trophic diversity curves. T. lepturus was a general omnivore, feeding primarily on Bregmaceros rarisquamosu, Decapterus maruadsi, and Acetes chinensis. Conversely, T. margarites preyed primarily on D. maruadsi, B. rarisquamosus, B. nectabanus, and A. chinensis. Both species exhibited distinct ontogenetic diet shifts. Although the two hairtail specie fed on similar sources in the same habitat, the diet overlap was relatively low. Our results suggest that hairtail play an important role in controlling small pelagic and benthic fish populations in the gulf. This trophic correlation shall be used for developing a marine ecosystem model for the Beibu Gulf. 相似文献
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根据2006年夏季(8月)和冬季(1月)、2007年春季(4月)和秋季(10月)在闽江口及其附近海域利用底拖网作业的渔业资源调查资料,应用传统扫海面积法以及△-分布模型法分析了福建闽江口及其附近海域(25°42′-26°27′N,119°42′-120°15′E)的渔业资源现存量.研究结果表明,闽江口及其附近海域的鱼类、甲壳类的资源密度较高,而头足类资源密度较低.渔业资源密度秋季居首位,约为2569.11kg·km-2,夏季次之,约为1 120.23kg·km-2,而冬、春季资源密度较低,分别为867.16和553.60.29kg·km-2.年平均渔业资源现存量约为4599t,渔业潜在资源量达32451t.渔业资源分布与水温、水深关系较密切.该海域渔业资源已经明显衰退,急需加强渔业资源的管理和保护. 相似文献
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南海5类重要经济鱼类资源声学评估 总被引:11,自引:0,他引:11
1997年12月至1999年6月,利用“北斗”号调查船配置的Simrad EK500回声探测-积分系统在南海北部海域进行了渔业资源声学调查,调查分春(4~6月)、夏(7~9月)、秋(10~12月)、冬(12~2月)4个季节进行.根据调查资料,运用渔业资源声学评估方法对该海域的带鱼科、蓝圆鲹、竹荚鱼、金线鱼科以及大眼鲷科等5类23种经济鱼类进行了评估与分析.结果表明,这些种类在南海北部海域仍具有一定的资源储量,其资源量分别为5.04×105,1.63×105,1.04×105,9.8×104和9.2×104t;分析了其资源量的区域分布和季节变化. 相似文献