长江干流圆口铜鱼的年龄与生长研究

采用鳞片材料对采自长江干流宜昌和重庆江段圆口铜鱼（Coreius guichenoti）的年龄进行鉴定,并对其生长方程、生长拐点等生物学特征进行了研究。结果表明,调查江段圆口铜鱼的年龄组成以1、2龄个体为主;体长（L）和鳞径（R）呈线性关系,L=15.327R＋71.349;体重（W）与体长（L）呈幂指数关系,W=0.00002L2.9942;体长von Bertalanfy生长方程为Lt=730.15[1-e-0.12（t＋1.01）];体重生长方程为Wt=7493.05[1-e-0.12（t＋1.01）]2.9942;其生长拐点年龄为8.13龄。圆口铜鱼体长生长3龄前为快速期,之后生长减缓。为了保护长江干流圆口铜鱼资源,建议以278mm为最小捕捞个体的体长。

Age and Growth of Coreius guichenoti in the Mainstream of the Yangtze River

Based on the scale materials fetched from the samples of Coreius guichenoti being collected from the Yichang section and the Chongqing section in the mainstream of the Yangtze River during the autumns of 2007 and 2008,Coreius guichenoti were aged by determining the annuli of scale.Moreover,information on growth features of Coreius guichenoti,including growth functions,growth index and inflexion point were studied.The relationship between body length and scale radius was lineal,which expression equation was L=15.327R＋71.349 and the relationship between body length and body weight was functionally power,which expression equation was：W=0.00002L2.9942.The von Bertalanffy growth function,was used to model the standard length growth of Coreius guichenoti using the original survey body length.The von Bertalanffy growth function were Lt=730.15 [1-e-0.12（t＋1.01）] and Wt=7493.05[1-e-0.12（t＋1.01）]2.9942.The von Bertalanffy growth function could provided a high goodness of fit and accurately described the growth of Coreius guichenoti by methods of the least square.The inflection point of body weight growth curve was 8.13 age.This fish grow rapidly in the first three years,then had slow growth after age 3 years.For the purpose of resource conservation of Coreius guichenoti,it should be restricted to bigger than 278 mm for the captured individuals in all sections.