乌苏里江大麻哈鱼年龄结构及异龄组间生长差异

Age composition and growth difference of chum salmon migrating to Ussuri River

摘要:

对乌苏里江大麻哈鱼生殖洄游群体样本进行年龄鉴定和生物学测定，推算了各年龄段的叉长，并分析了性成熟年龄组间个体的生长差异性。年龄鉴定结果显示大麻哈鱼由2+，3+，4+ 龄群体组成，雌、雄大麻哈鱼平均年龄分别为3.43和3.24龄。采用Von Bertalanffy 生长方程（VBGF）拟合了大麻哈鱼各性成熟年龄组个体的叉长生长。基于VBGF生长方程的拟合结果，采用残差平方和（analysis of the residual sum of squares, ARSS）分析各年龄组间大麻哈鱼的生长差异性，结果显示不同性成熟年龄组间的大麻哈鱼生长的差异性显著（P<0.05）。大麻哈鱼低龄组个体叉长生长速度较快，高龄组个体生长相对较慢，随着年龄的增加生长速度减慢，但是末年的生长指标却不是最低。大麻哈鱼的生长发育受遗传、海洋环境条件、种内、种间竞争等因素的共同影响。

Abstract:

Age determining and biological parameters measuring were conducted for the chum salmons collected form the stocks migrating to Ussuri River for breeding. Back calculated fork length was computed and the difference of growth between different maturation age groups was studied based on it. The result showed that the age groups of chum salmon were composed by 2+，3+，4+ age group, and female and male individuals have different age composition, average age are 3.43 and 3.24 respectively. Von Bertalanffy growth function was used to fit the fork length growth of chum salmon. ARSS（Analysis of the residual sum of squares）was used to judge the difference of chum salmon among the three age groups. The result showed the growth of chum salmons at different maturation age group has significant difference (P<0.05).The stocks at low maturation age group grow faster than the high age groups. With the age increasing growth speed become slower, but the growth index is not the smallest one at the last year in the ocean life stage. Genetic factor, Ocean environment conditions, intra and interspecific interaction affect the growth of chum salmon all together.