摘要
研究鱼类的年龄结构与生长特性可为评价天然水体野生资源的动态变化提供理论依据,鳞片是低龄鱼可靠的年龄鉴定材料;由于营养不足和水环境因素的影响,高龄鱼出现年轮被机体重吸收、鳞片生长明显慢于机体生长的现象,导致用鳞片鉴定年龄的准确性明显降低。以2008年1月至2010年1月采集于乌江上游总溪河的113尾四川裂腹鱼（Schizothorax kolzovi）为材料,对比臀鳞、脊椎骨、鳃盖骨和微耳石材料并鉴定年轮,研究其年龄与生长的关系。结果表明,四川裂腹鱼体长和体重在雌雄群体间的差异不显著（P〉0.05）,体重（W;g）和体长（L;mm）拟合关系式为W=0.00002L^2.9511（R^2=0.9543,n=113）;对比选择臀鳞鉴定年龄、测量鳞径,并建立von Bertalanffy生长方程,Lt=598.39[1-e^-0.0929（t＋3.3636）]和Wt=3134.65[1-e^-0.0929（t＋3.3636）]2.9511。采集的四川裂腹鱼群体由1～4龄组成,优势年龄组为3龄,占标本总数的57.5%,年龄结构趋于低龄化;体重生长拐点年龄为8.3龄,对应的体长和体重分别为395.62 mm和924.39 g。
Age structure and growth characteristics of fish populations provide a theoretical basis for assessing the fishery resource in a water body. Schizothorax kolzovi Nikolsky is an economically important fish species inhabiting the upper reaches of Wujiang River. The population has sharply declined in recent years and this has had negative effects on the aquatic ecology of the upper Wujiang River. In this study,the age structure and growth of Schizothorax kolzovi Nikolsky in the upper Wujiang River were characterized using the anal scales to age fish. Age determination by anal scales was compared with fish ageing by vertebra,opercula and lapillus and the agreement was good.A total of 113 Schizothorax kolzovi Nikolsky individuals were collected by gill net（ mesh： 3. 5- 5. 0 cm） in the Zongxi section of the upper Wujiang River from January 2008 to January 2010. The body length and body weight of each specimen were measured immediately after being taken to the laboratory in an oxygen bag. The sex of each fish was recorded and fish were dissected. Gonad weight and development phase were recorded and gonads were fixed in5% formaldehyde. There were no significant differences between female and male body length or body weight（ P〉^0. 05）. The relationship between body weight（ W; g） and body length（ L; mm） was described by the linear equation： W = 0. 00002L^2. 9511（ R^2= 0. 9543,n = 113）. The growth pattern of Schizothorax kolzovi Nikolsky was described by the Von Bertalanffy equation as Lt= 598. 39 [1- e- 0. 0929（ t ＋ 3. 3636）] and Wt=3134. 65[1- e^- 0. 0929（ t ＋ 3. 3636）]2. 9511,based on the age and scale radius. The fish collected ranged in age from one to four years,dominated by three year-old individuals（ 57. 5%） but the trend was toward younger,smaller fish. The inflection point of the growth curve occurred at 8. 3 years with a body length of 395. 62 mm and weight of 924. 39 g.Our research indicates that the population has been overexploited and strategies should be developed for the improving fisheries management and resource conservation.
出处
《水生态学杂志》
CSCD
北大核心
2015年第2期75-80,共6页
Journal of Hydroecology
基金
贵州省教育厅自然科研重点项目(黔教科2006219)
贵州省农业科技攻关项目(黔科合NY字[2008]3)
关键词
四川裂腹鱼
年龄结构
生长特性
乌江
Schizothorax kolzovi Nikolsky
age structure
growth characteristics
Wujiang River
