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首页> 外文期刊>CCAMLR science: journal of the Scientific Committee and the Commission for the Conservation of Antarctic Marine Living Resources >Analysis of changes in biomass of fish stocks in the South Georgia area in 1976/77-1986/87
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Analysis of changes in biomass of fish stocks in the South Georgia area in 1976/77-1986/87

机译：1976 / 77-1986 / 87年南乔治亚地区鱼类种群生物量的变化分析

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The swept area method was used to estimate biomass density changes in the stocks of five fish species (Champsocephalus gunnari, Chaenocephalus aceratus, Pseudochaenichthys georgianus, Notothenia gibberifrons and Notothenia rossii marmorata) in the South Georgia area in the seasons 1976/77-1986/87. In most of the seasons analysed, the estimates covered a near-bottom layer in about 1/6 of the area of the island shelf. Assessment results point to considerable variations in fish biomass density, in the studied period. Estimates of fish stocks biomass ranged from 43 to 158 thousand tons. The changes in the biomass level are first of all a result of periodical fluctuations in the biomass density of C. gunnari stock. High biomass density appeared with 2-4 year intervals after recruiting an abundant year-class to the exploited stock. The biomass of other bottom species is more stable, especially in the case of N. gibberifrons. Recently, an increase in the C. aceratus stock has been observed and, at the same time, there has been a gradual decline in the P. georgianus stock.
机译：扫描面积法用于估计1976 / 77-1986 / 87季南乔治亚地区五种鱼类（Champsocephalus gunnari，Chaenocephalus aceratus，Pseudochaenichthys georgianus，Notothenia gibberifrons和Notothenia rossii marmorata）种群生物量密度的变化。 。在所分析的大多数季节中，估计值覆盖了岛架面积约1/6的近底层。评估结果表明，在研究期间鱼类生物量密度发生了很大变化。鱼类资源生物量估计为43至15.8万吨。生物量水平的变化首先是冈氏梭菌种群生物量密度周期性波动的结果。在为被开发的种群募集了丰富的年级资源之后，高生物质密度每隔2-4年出现一次。其他海底物种的生物量更稳定，尤其是在赤霉猪笼草的情况下。最近，已经观察到了铜角藻存量的增加，与此同时，格鲁吉亚角藻的存量也逐渐减少。

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