长江中游武汉江段铜鱼的年龄与生长

Age and growth of Coreius heterodon from Wuhan stretch of the middle Yangtze River

  • 摘要: 为了解长江中游武汉江段铜鱼种群的年龄和生长特征,2017年7月—2018年12月,在武汉江段逐月收集了435尾铜鱼样本的基础生态学数据、年龄鉴定材料,并进行数据分析和年龄鉴定。结果显示,样本体长分布范围为152.1~325.2 mm,平均体长(233.2±73.4)mm;体质量分布范围为33.1~429.8,平均体质量(182.40±85.4) g。样本年龄由 1~5 龄组成,其中 2 龄和 3 龄组为优势组,占总体的75.6%。雌雄性别比例为1∶1.07,与1∶1相比没有显著性差异,但在不同的体长组中差异显著,其中雄性在小型个体中居多,而雌性则在大型个体中占据优势。鳞片边际增长率分析表明,年轮形成周期为1年,形成时间在一年中的7—9月,与水温有关。总体(♀+♂)体长—体质量呈幂函数指数关系:W=7×10-6L3.11(R2=0.963 3),属于匀速增长类型,且雌雄之间无显著性差异;种群体长—鳞径呈线性关系:L = 52.983R + 72.439 (R2 = 0.678)。总体(♀+♂)生长符合von Bertalanffy 生长模型,其体长生长方程:Lt=482.7 1−exp −0.22 (t+0.25);体质量生长方程:Wt=1 573.7 1−exp−0.22 (t+0.25)3.11。生长的拐点年龄为5.15龄,对应的体长和体质量分别为335.6 mm和501.7 g。研究表明,武汉江段铜鱼属于匀速生长类型;种群年龄结构简单,生长速率较慢,需要采取相关保护措施。

     

    Abstract: To reveal the age and growth characteristics of Coreius heterodon, we collected 435 specimens from Wuhan stretch, Yangtze River, between July 2017 and December 2018. The result showed that the body length ranged from 152.1 to 325.2 mm with the mean of (233.2±73.4) mm, and that the body weight ranged from 33.1 to 429.8 g, with the mean of (182.40 ± 85.4) g. The age ranged from 1 to 5 years and the dominant population with the mean of 75.6% was of individuals of 2 and 3 years. Although there was no significant difference between the sex ratio (male: female) of 1∶1.07 and 1∶1, there was significant difference in different body length groups. The female dominated in large individuals, while the male dominated in small individuals. The marginal increment ratio (MIR) of scales showed that the formation time of age was from July to September. The relationship between body length and body weight was described by the equation: W=7×10-6L3.111(R2=0.963) and significant difference was not found between both sexes in the length-weight relationship. The relationship between body length and scale radius was described by the equation: L=52.983R+72.439 (R2=0.678). The Von Bertalanffy growth function was Lt=482.7 1−exp −0.22 (t+0.25); Wt=1 573.7 1−exp−0.22 (t+0.25)3.11, respectively. The inflection point age of growth was 5.15 years, and the corresponding body length and weight were 335.6 mm, and 501.7 g, respectively. C. heterodon in Wuhan, Yangtze River had a simple age structure with slow growth rate. It is urgent to take necessary measures to promote the spread of its population.

     

/

返回文章
返回