大渡河上游麻尔柯河高原鳅的年龄与生长

研究了采自大渡河上游麻尔柯河及其支流则曲的129尾麻尔柯河高原鳅(Triplophysa markehenensis)的年龄结构和生长特性。结果表明,耳石和脊椎骨都可作为年龄鉴定的材料,其中耳石是进行年龄鉴定的最适材料,脊椎骨则可作为辅助材料;背鳍条不适合用于年龄鉴定。这批麻尔柯河高原鳅的年龄范围为2～8龄,以3～6龄居多,占总数的83.5%;体长体重呈幂函数关系:W=0.000015L2.951931;Von Bertalanffy生长方程为:Lt=173.12411-e-0.1597(t+0.5328)],Wt=60.75311-e-0.1597(t+0.5328)]2.9519;体重生长曲线的拐点为t=6.25,拐点时体长为114.5mm,体重为17.9g。关键词:耳石;脊椎骨;年龄;生长

Age and Growth of Triplophysa markehenensis from the Markehe River in Upper Reaches of the Dadu River

Age structure and growth characters of 129 Triplophysa markehenensis collected from the Markehe River and its tributary,Zequ,in upper reaches of the Dadu River were investigated and analyzed. The characteristics of three kinds of age identification materials of T. markehenensis,otolith,vertebra and last unbranched dorsal-fin ray,had been described and compared. The results showed that both otolith and vertebra could be used for age identification of the species,and otolith is more appropriate compared with vertebra, which could be used as accessory identification material. However,the unbranched dorsal-fin ray is not suitable for age identification in this species. Age of the fishes was identified to seven age classes (2-8 years old), and individuals of 3-6 years old were dominated with a frequency of 83.5% . The regressed equation between body weight (W) and body length (L) is W=0.000015 L^2.951931 (R²=0.967 3). Growth model of the species was described using Von Bertalanffy equation: L_t=173. 124 11-e^{-0.159 7(t +0.5328)} ],W_t=60.753 11-e^{-0.159 7(t +0.5328)} ]2.9519 . Growth inflexion occurred at 6. 25 years,when body length is 114. 5 mm and body weight is 17.9 g.