The sinking performance which is directly related to the fishing efficiency is the most important performance of the purse seine. Study on the effect of different factors on sinking performance of the tuna purse seine by model test has important significance of improving the sinking performance of purse seine. Based on the tuna purse seine model test at Qiandao Lake (Thousands Island Lake), Zhejiang Province between October 24 and 26,2009, study was conducted on the effect of leadline weight and setting speed on sinking speed of the tuna purse seine lead line by GLM model. The results showed that: (1) The lead line weight and the net setting speed had significant effect on sinking speed of lead line (P < 0. 05), but the interaction effect caused by the above two factors are not significant(P >0. 05). (2) The sinking speed of the middle and aft parts was significantly higher at 0.795 kg/m of the leadline weight than at other level of leadline weights used. The relationship between the sinking speed of the middle part of the lead and weight of the leadline can be described as the function: V = 0. 114 6w+ 0. 103 2 (R2 = 0. 871). (3) The sinking speed of lead line increased with the setting speed. The sinking speed of the forepart and aft-part was significantly higher at 1.05 m/s of the net setting speed than at other levels of net setting speed used. The relationship between the sinking speed of the middle part of the leadline and the net setting speed in pool way can be described as the following function: V =0. 072 6s +0.113 8(R2 =0.983).%作为围网网具主要性能,沉降性能直接关系到围网作业的捕捞效率,通过模型试验研究不同因素对金枪鱼围网沉降性能的影响,对改进金枪鱼围网沉降性能具有重要意义.本文通过2009年10月24-26日在千岛湖进行的金枪鱼围网模型试验,采用一般线性模型(GLM)分析下纲重量和放网速度对围网下纲沉降速度的影响.结果表明:(1)下纲重量和放网速度对下纲各部分沉降速度均有显著影响(P＜0.05),但两者间交互作用不明显(P＞0.05).(2)下纲重量在0.795 kg/m时,下纲中部和后部沉降速度明显比其它组快(P＜0.05)；下纲中部沉降速度和下纲重量间关系式为:V=0.114 6w +0.103 2(R2 =0.871).(3)随放网速度变快,围网下纲沉降速度加快,在放网速度为1.05 m/s时,下纲前部和后部沉降速度明显比其他组快(P＜0.05)；下纲中部沉降速度和放网速度间关系式为:V=0.072 6s +0.113 8(R2=0.983).
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