集鱼灯灯光分布及茎柔鱼钓捕效果分析

Analysis on intensity of illumination distribution of gathering-fish lamp and its fishing efficiency in the squid jigging of Dosidicus gigas

根据2006年4—6月我国鱿钓船在智利外海茎柔鱼渔场实际测定的灯光分布和生产统计资料，对金属卤化物灯和高压钠灯的光照度分布及其钓捕效果进行了比较分析。经测定分析和模型拟合，金属卤化物灯和高压钠灯的灯光衰减曲线符合指数模型，金属卤化物灯和高压钠灯的衰减系数分别为0．1998和0．6353。在180盏×2kW金属卤化物灯情况下，在距船舷2m的垂直断面，其水深5m内的光照度多在100lx以上，10lx的等光照度曲线在18m水层左右，0．01lx的等光照度曲线在40m水层附近。在30盏×500w高压钠灯情况下，在距船舷2m的垂直断面，其海面的平均光照度为10lx左右，0．01lx的等光照度曲线在20m水层附近。以一些头足类的适宜光照度0．01～10lx估算，30盏×500w高压钠灯适宜照度的水体体积仅为180盏×2kW金属卤化物灯的1／8左右。研究还表明，钓捕茎柔鱼时的金属卤化物灯适宜总功率为260—274kW。

On-the-spot experiments of different kinds of gathering-fish lamps were carried out in the fishing ground of Dosidicus gigas in the high sea waters off Chile from April to June in 2006, and the illumination distribution of gathering-fish lamp and the fishing efficiency were studied. The results indicated that the illumination intensity is fitted by the Exponent model, and the declining coefficients of metal halide lamp and high pressure sodium lamp are estimated to 0. 199 9 and 0. 635 3 respectively. When the output of metalhalide lamps is 360 kW, for the vertical section leaving to 2 m of shipside, the intensity of illumination above 5m water is more than 100 lx, the iso-illuminance curve of 10 lx is in the depth of 18 m, and the isoilluminance curve of 0.01 lx is in the depth of 40 m. When the output of high pressure sodium lamps is 15 kW,the average intensity of illumination on the sea surface is about 10 Ix, and the iso-illuminance curve of 0.01 lx is in the depth of 20 m. According to the suitable intensity of illumination from 0.01 lx to 10 lx for oceanic squids, the ratio which is the dimension of suitable attracting squid of high pressure sodium lamps to that of metal halide fish lamps is 1 ： 8. It also shows that the suitable total power should be 260 to 274 kW for fishing Dosidicus gigas.