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为了解长江刀鲚Coilia nasus资源的变动状况,探讨沿岸水域对刀鲚资源的保育作用,于2002~2013年间用定制张网对长江靖江段沿岸鱼类作了每月2~3个样本的采集。分析结果显示,12a采集的369份样品中,刀鲚的出现频率达94.6%,分别占总渔获数量和重量的5.18%和5.46%。刀鲚平均CPUEN和CPUEW有16.7±19.9尾和106.6±109.5g,是沿岸鱼类群聚的优势种或次优势种。但其年资源量并不稳定,最高的2010年是最低2002年的5.4陪。平均体长123.6±37.0mm,平均体重仅7.5±8.2g。0+龄组占78.9%,1+龄组占20.7%,2+龄仅出现在4、5月份,且仅占当月个体数的3.0%,幼体是沿岸刀鲚群体的主要组成成分。从0+龄个体的月度体长分布看,当年孵化的幼鱼大多栖息在河岸水域,沿岸生境在维持刀鲚幼鱼资源上具有重要作用。分析显示,4月1日至6月30日的长江禁渔期虽可保护约42.6%的幼鱼个体,但从保护效果看,还因适当延长沿岸水域的禁渔时间。维护沿岸水域的生境完整性,也是保护长江刀鲚幼鱼资源的重要措施。
In order to understand the changes of the resources of the Coilia nasus in the Yangtze River and to explore the conservation effect on the resources of the lakes in the coastal waters, two to three samples per month were collected from the coasts along the Jingjiang section of the Yangtze River by a custom- . The analysis showed that among the 369 samples collected in 12a, the frequency of occurrence of Daphnia magna reached 94.6%, accounting for 5.18% and 5.46% of the total number and weight of the catch respectively. The average CPUEN and CPUEW of knives were 16.7 ± 19.9 tails and 106.6 ± 109.5g, which were the dominant species or subdominant species of fish clustering along the coast. However, its annual resources are not stable, the highest in 2010 is the lowest in 2002 to accompany 5.4. The average body length was 123.6 ± 37.0 mm and the average body weight was only 7.5 ± 8.2 g. 0 + age group accounted for 78.9%, 1 + age group accounted for 20.7%, 2 + age only in April and May, and only accounted for 3.0% of the individual month, larvae are the main component of the Cynanchum mollis population. According to the distribution of monthly body length of 0+ individuals, the hatchling larvae mostly inhabit the riparian waters, and the coastal habitats play an important role in maintaining the resources of the larvae. According to the analysis, from April 1 to June 30, about 42.6% of juvenile larvae could be protected during the fishing ban of the Yangtze River. However, due to the protection effect, the time of no-fishing in coastal waters was appropriately extended. Maintaining the habitat integrity of the coastal waters is also an important measure to protect the juvenile resources of the darter.