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于2010—2012年,在长江南支宝山水域和北港水域设置调查断面,研究了长江口刀鲚渔获规格、渔汛特征及捕捞量。结果表明:调查期内刀鲚汛期平均全长为(316±36)mm,平均体长为(294±35)mm,平均体重为(99±37)g;单船全汛捕捞量为65.9～875.4kg,均值为338.7kg;日均捕捞量变幅为2.3～23.4kg·d-1,均值为9.4kg·d-1;长江口刀鲚汛期有证总捕捞量为8.2～109.4t,平均为42.3t;宝山水域单船捕捞量各项指标均低于北港水域;2010—2012年刀鲚发汛时间最早为2月23日,最晚为3月5日,3月末—4月中旬为旺汛期,旺汛期捕捞量比例为60.96%～82.62%;刀鲚汛期捕捞量与水温和潮汛关系密切,通常水温升至12℃附近时开始进入旺汛期,各年份最高日捕捞量对应的水温介于13℃～14.5℃,平均为13.7℃;调查期间低潮期捕捞量占汛期总捕捞量的比例显著高于高潮期,其中低潮期捕捞量比例最高为82.97%,最低为62.05%。
In 2010-2012, a survey section was set up in the Baoshan water area and the north harbor of the southern part of the Yangtze River to study the catch size, fishing season characteristics and catch of the riparians in the Yangtze Estuary. The results showed that the average length of the knives in the flood season was (316 ± 36) mm, the average body length was (294 ± 35) mm and the average body weight was (99 ± 37) g in the flood season; 875.4kg, with an average of 338.7kg. The average daily catches ranged from 2.3 to 23.4kg · d-1 with an average of 9.4kg · d-1. The total amount of catches in the flood season was 8.2-109.4t, with an average of 42.3t; Baoshan waters single-hull fishing indicators are lower than the North Harbor waters; 2010-2012 knives Dai hair flood time as early as February 23, the latest March 5, the end of March to mid-April Wang In flood season, the catchments in flood season are 60.96% -82.62%. The catch of Daphnia magna in flood season is closely related to water temperature and flood season. Usually, the water temperature starts to enter the peak flood season when the water temperature rises to around 12 ℃. At 13 ℃ ~ 14.5 ℃, the average was 13.7 ℃. During the survey period, the proportion of low-tide catch in total catch in flood season was significantly higher than that in high-tide period. The highest catch at low tide was 82.97% and the lowest was 62.05%.