低气压对渔获量的关系

气压变动能引起渔获量显著的变动,这是渔民在长期生产实践中所了解的事实,在国内过去的文献中,也曾有些记载,在国外,日本学者多从数理统计方法着手,曾进行了低气压对渔获量丰、歉的影响等研究。 探明低气压对渔获量的关系,可为渔情预报提供渔获丰、歉的依倨,对掌握渔场,提高产量来说,具有重大意义。 在本文中根据历年渔汛资料,讨论了低气压对小黄鱼、大黄鱼及带鱼渔获量的关系。小黄鱼是根据1957—1964年吕泗渔场春汛(4—5月)资料;大黄鱼是根据1961—1964年吕泗渔场春汛(5—6月)资料;带鱼是根据1963年舟山渔场冬汛(11—12月)资料。

NOTES ON THE RELATION OF LOW BAROMETRIC PRESSURE TO THE CATCHES OF SOME MARINE FISHES

By analysing the fishing records of the great yellow croaker, Pseudosciacna crocea (Ric-hardson), in spring fishing seasons of 1957-1964, the lesser yellow croaker, Pseudosciaenapolyactis (Bleeker), in the period 1961-1964, in Luzi-yang Fishing Ground, and the ribbon-fish, Tri chiurus haumela (Forskal) in winter fishing season along the coast of Choushan Is lands,the author found that low barometric pressure exerted obvious effect on the catches of thethose important commercial fishes. Several instances illustrating the said relation were brie-fly cited with the help of fish-finding echograms, and dense shoals of the above mentionedspecies under low barometric pressure were also demonstrated. A few points of the results observed may be noted: 1. There is a tendency when the barometric pressure drops down, a much larger dailycatch of these fishes could be anticipated. The catches may rise significantly if the baromet-ric pressure drops down to bolow 1010 milibars, and as long as the low barometric pressurepersists, high catches may sustain. 2. The effect of lower barometric pressure on the catch of the great yellow croakers issimilar to that of the lesser yellow croakers. 3. During the winter fishing season of the ribbon fishes at the Chou shan Fishing Ground,our observation disclosed that, under low barometric pressure of 1021 milibars, the fish shoalswere moving upward towards upper layer of 20 meters, but they started to swim downwardto medium or benthic region as soon as the barometric pressure rose above 1026 milibars. 4. The influence of low barometric pressure is variable in different sea regions.