摘要
认识鱼类的生活史特征及其对生态环境变化的响应,是鱼类物种保护与资源合理利用的基础。于2009年5月至2010年4月研究了黄山地区徽水河中宽鳍鱲(Zacco platypus)的年龄、生长和繁殖。共采集标本352尾,雌雄性比为0.49∶1,与1∶1差异显著。以鳞片为年龄鉴定材料,雌、雄个体的最大寿命均为3龄;年轮主要形成于3月份。全长和体重呈幂函数关系,两性间无显著性差异,关系式表达为W=6×10–6L3.10;全长和鳞径呈线性关系,且两性间差异显著,关系式分别表达为L♀=29.58R+38.84和L♂=33.17R+34.99;2龄个体的退算全长在雌、雄两性间无显著性差异。繁殖时间为4—7月份;2龄时达50%初次性成熟,其个体全长为98.22(雌)和105.69 mm(雄);绝对繁殖力为(758±362)卵粒,相对繁殖力为(77.38±22.15)卵粒/g。同已有的少量研究资料相比较,徽水河宽鳍鱲的年龄结构较北京地区种群的相对简单,个体生长较同为黄山地区的浦溪河种群相对快速,这种生活史特征差异可能是生态环境空间异质性的作用结果,但有关宽鳍鱲各生活史特征之间的权衡及其对生态环境的响应还有待于进一步研究。
Identifying the life history of fishes is the basis for scientifically protecting fish species diversity and rea- sonably managing fishery resources. In this study, age, growth and reproduction of Zacco platypus in the Huishui Stream were examined using 352 specimens collected monthly from May 2009 to April 2010. Sex ratio was 0.49 : 1 (female: male), which was significantly different from 1 : 1 by ;(2 test. Using scales for age determination, the largest longevities were both age 3 for females and males. Based on the monthly changes in marginal increment ratio (MIR), annuli on scales were formed during March, which was associated with the relatively low water temperature constrain- ing the somatic growth in winter. The relationships between total length (L) and weight (W) were W = 5x10 6L3A5 for females and W = 7×10^-6L^3.09 for males. Due to no significant difference discovered by ANCOVA between sexes, L-W relationship was combined as W= 6×10 ^-6L^3.10for both sexes. L-R (scale radius) equations were L = 29.58R + 38.84 for females and L = 33.17R + 34.99 for males, and significant difference was observed between them. The back-calculated total lengths (BCL) at age 2 were (82.59 ±9.77) mm for females and (84.65 ±11.77) mm for males, and those age 3 were 120.56 mm (only one specimen) for females and (94.97±9.85) mm for males. According to t-test result, no sig- nificant difference was observed in BCL at age 2 between the two sexes. The monthly changes in gonado-somatic index (GS1) suggested that Z. platypus spawned from April through July, which was almost synchronous with local flooding period, because flood could bring sufficient food for larva and decrease the risk that larva were preyed by predators. Fifty percentage of individuals got the first maturity at age 2, when the average total lengths were 98.22 mm for females and 105.69 mm for males. In terms of the number of the occytes with vitellinogenic granules from mature ovaries, the absolute fecundity (AF) and relative fecundity (RF) were (758±362) eggs and (77.38±22.15) egg/g. Comparing the observed results in this study with those in limited others, the age structure of the population of Z. platypus in the Hu- ishui Stream was similar with that in the Puxi Stream but not with that in Beijing region. In addition, somatic growth of Z. platypus was faster in the Huishui Stream than that in the Puxi Stream, which was suggested by their difference in the back-calculated length at each age. These variations in the life history among different populations of Z. platypus were possibly associated with the spatial heterogeneity in ecological environment. However, the future studies should be op- erated to identify how this species trades off among different life-history variables (i.e., age and body size at sexual maturity, longevity, fecundity, and somatic growth rate) and how environment influences the trade-off in life history.
出处
《水生生物学报》
CAS
CSCD
北大核心
2012年第3期474-481,共8页
Acta Hydrobiologica Sinica
基金
国家重点基础研究发展计划项目(2009CB119200)
国家自然科学基金(31172120)
安徽省自然科学基金(090413080)
安徽省教育厅自然科学基金(KJ2009A110,KJ2008B221)资助
关键词
宽鳍鱲
年龄
生长
繁殖
徽水河
Zacco platypus
Age
Growth
Reproduction
The Huishui Stream