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湖鲚鳞片年轮可作为年龄鉴定的依据,其边缘增长率K的周年变化,表明年轮系一年形成一次,主要在4—6月出现。体长与鳞长的关系式为L=18.658+118.06R,与体重关系式为W_♀=7.588×10~(-6)L~(2.8301)、W_♂=5.584×10~(-6)L~(2.8781)。2龄鱼以前,体长和体重相对增长率与生长指标较大,2龄以后则相反。生长适合Von Bertalanffy生长方程,体重生长曲线的拐点位于2—3龄的W=0.292W_∞处;生长速度和加速度曲线能反映生长过程的变化特征,合理的捕捞年龄应为2龄以后,体长为170mm以上。本文为提高太湖湖鲚产量提供了重要依据。
The annual growth rate of Lake Kochia scoria can be used as the basis for age identification. The annual growth rate of K shows that annual ring system formed once a year, mainly in April-June. The relationship between body length and scale length was L = 18.658 + 118.06R, the body weight was W_♀ = 7.588 × 10 ~ (-6) L ~ (2.8301), W_♂ = 5.584 × 10 ~ (-6) L ~ (2.8781). Before 2-year-old fish, the relative growth rate and growth index of body length and body weight were larger than those of 2-year-old fish. The growth curve is suitable for Von Bertalanffy growth equation, and the inflection point of body weight growth curve is located at W = 0.292W ∞ of 2-3 instars. The growth rate and acceleration curve can reflect the changing characteristics of growth process. Reasonable fishing age should be 2 years old. 170mm or more. This article provides an important basis for improving the yield of Lake Taihu.