东海发光鲷的年龄与生长特性

Age and growth characters of Acropoma japonicum in the East China Sea

2005年8月-2006年7月在东海采集发光鲷(Acropoma japonicum)样本共848尾,测定其渔业生物学参数,观察耳石的生长轮,分析性腺成熟系数(GSI)的变化,采用von Bertalanffy、逻辑斯谛(Logistic)、Ricker生长模型分别拟合其生长方程,研究发光鲷年龄和生长特性。结果表明,东海发光鲷叉长范围在14～110mm,平均叉长为54.16mm;群体年龄组成由当龄鱼和1龄鱼构成,并以当龄鱼为主,占63.31%,当年冬季形成年轮;产卵高峰期为8月。8月为其新世代的起始月,9月为1月龄,依次类推。叉长(L)与体质量(W)关系雌雄间无明显差异,其表达式为W=2.73×10-5L2.99(R2=0.937,P<0.001);叉长与耳石轮径(r)关系雌雄间无明显差异,其表达式为L=8.10+25.3r(R2=0.850,P<0.001)。生长方程拟合结果以Ricker指数生长模型效果最佳,东海发光鲷生长分为3个阶段,第1阶段:9-12月,为发光鲷世代发生后的快速增长期,生长方程为Wt=0.100×e1.26(t-1)(1<t≤4,R2=0.834,P<0.001);第2阶段:12月-翌年4月,为发光鲷世代生长过程中的相对缓慢期和年轮形成期,生长方程为Wt=4.32×e0.14(0t-(4)4<t≤8,R2=0.967,P<0.001);第3阶段:4-8月,为发光鲷世代的摄食高峰快速增长期,生长方程雌性为Wt=8.70×e0.18(9t-(8)8<t≤12,R2=0.987,P<0.001),雄性为Wt=8.70×e0.1(7t-(8)8<t≤12,R2=0.754,P<0.001)。因此,用Ricker生长方程来表达东海发光鲷的生长规律更为科学。

The samples were collected monthly in the East China sea （29° 30′ -33° 00′ N, 125° 00′ -128° 00′ E） from August 2005 to July 2006 （848 individuals totally）. In the study, we obtained their biological parameters and the total number of growth rings of otolith, then analyzed the monthly variation of GSI and applied von Bertalanffy, Logistic and Richer growth equations to fit Acropoma japonicum＇s growth curve. The results showed that the fork length of individuals ranged between 14 and 110 ram, and the mean fork length amounted to 54.16 ram. The stock of Acropoma japonicum was composed of young-of-the year （YOY） and 1-age individuals. The majority of individuals were YOY, which accounted for 63.31% of the stock in number. Moreover,2-age individual wasn＇t observed. The opaque zone was formed in winter. The main spawning period was August. The relationship between weight and fork length showed no significant difference between male and female, which was expressed as： W=2.73 × 10^-5L^2.99 （R^2=0.937, P〈0.001）. The relationship between fork length and otolith length also showed no significant difference between male and female, which was expressed as： L=8.10＋25.3R （R^2 = 0.850, P〈0.001）. Three growth equations were applied to fit Aeropoma japonieum＇s growth disciplinarian. The results showed that the Richer equation was the best one. According to Richer equation, the weight growth equation for male and female was divided into three stages. The fn,st stage was from September to December. In this period, the new generation grew fast. The equation was expressed as： Wt=0.100 × e^1.26 （t-1）（1〈t ≤ 4, R^2=0.834, P〈0.001）. The second stage was from December to the April of coming year＇s. In this period the new generation grew slowly and the growth ring was formed .The equation was expressed as： Wt=4.32 × e^0.140（t-4） （4〈t ≤ 8, R^2=0.967, P〈0.001）. The third stage from April to August. In this period, Aeropoma japonieum grew fast too, and there was significant difference of Richer model equations between male and female. They were expressed as follows： Wt=8.70 × e^0.189（t-8）（8〈t ≤ 12, R^2=0.987, P〈0.001） for female, and Wt=8.70 × e^0.171 （t-8） （8〈t ≤ 12, R^2=0.754, P〈0.001） for male. It was tested that the Richer growth equation is a more reasonable was of expressing the growth characters of Aeropomajaponieum.