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研究围网网具生产作业性能,对于研究人员设计金枪鱼围网及渔业从业人员改进捕捞操作具有重要的参考作用。本研究根据大型金枪鱼围网渔船在中西太平洋作业时所搜集的网具数据,系统分析了网具在沉降及提升阶段,网具下纲各个部位的沉降深度、沉降速度及提升深度和提升速度的变化情况。结果表明:(1)网具自然沉降深度从取鱼部到后网头呈依次递增趋势,最大沉降深度则呈现中部高,两端低的趋势,绞纲对于网具沉降具有显著影响;(2)网具自然沉降速度从取鱼部到后网头呈现递减趋势,下纲各个部位平均沉降速度则较为一致,维持在0.16 m·s-1左右;(3)在提升过程中,网具两端最先被提升,中部最后被提升,且网具在水下60~80 m完成包围;(4)网具下纲各个部位提升速度先缓慢上升,后快速增加,包围完成后快速下降。
Researches on the performance of the seine net with production operations are of important reference for researchers to design tuna seine and fisheries practitioners to improve fishing operations. Based on the data of the nets collected during the operation of large tuna seine fishing vessels in the Western and Central Pacific Ocean, this study systematically analyzed the settlement depths, settlement velocities, depths and velocities of the nets in the subsidence and enhancement phases of the nets, Changes. The results showed that: (1) The natural settlement depth of the net increased gradually from the fish-receiving part to the post-net, and the maximum settlement depth showed a high central part and a low tendency at both ends. ) The natural settlement speed of the net decreased gradually from the fish-receiving section to the net and the average sedimentation velocity of each section was relatively consistent, maintaining at 0.16 m · s-1. (3) During the lifting process, The end was first lifted, the middle was finally lifted, and the nets were surrounded by underwater 60 ~ 80m; (4) The lifting speed of various parts of nets was slowly increased at first, then rapidly increased, and then quickly decreased after the nests were completed.