基于耳石微结构的长江口凤鲚生长发育特性研究

发布时间：2018-06-23 07:10

本文选题：凤鲚 + 耳石　；参考：《上海海洋大学》2017年硕士论文

【摘要】：凤鲚(Coilia mystus)俗称凤尾鱼、小鲚鱼,属鲱形目(Clupeiformes),溊科(Engraulidae),鲚属(Coilia),主要栖息于河口及邻近水域。我国黄渤海、东海和南海均有分布,是长江口重要的经济鱼类。由于水利工程建设、环境污染等原因,长江口凤鲚资源已出现衰退。为更好的保护利用凤鲚资源,本文从年龄结构、生长特性、生活史类型以及仔稚鱼生长发育等方面进行研究和探讨。主要研究结果如下:1.长江口凤鲚繁殖群体的年龄结构和生长特性2014年4月~8月于凤鲚繁殖盛期在长江口逐月采样,对凤鲚繁殖群体的雌性个体的年龄结构和生长特性进行了研究。年龄结构为1~3龄,共3个年龄组,其中1~2龄个体占87.06%。繁殖群体的平均体长和体重分别为151.66±21.13mm、16.97±6.34 g。体长与体重关系为(n=124,R2=0.9353),显著性差异检验表明凤鲚属于匀速生长类型(P0.05)。体长和体重von Bertalanffy生长方程分别为:,。体长生长速度曲线不具拐点;体重生长速度的拐点年龄为1.11龄,与最小性成熟年龄一致,拐点年龄时对应的体长和体重分别为131.02 mm和11.05 g。结论认为,长江口凤鲚繁殖群体低龄群体所占比例较大且体型有变小趋势。为更好地利用和保护凤鲚资源,应在拐点年龄之后进行捕捞。2.长江口凤鲚仔稚鱼不同发育阶段矢耳石生长2014年4~8月于凤鲚的主要繁殖期在长江口采集仔稚鱼103 ind。分析凤鲚仔稚鱼样本得出日龄范围为5~48 d,其体长在4.20~26.21 mm之间。为研究长江口凤鲚早期发育不同阶段生长,测定了凤鲚仔稚鱼(5~48日龄)体长随日龄的生长变化,其变化分为3个阶段(5~11日龄,12~30日龄,31~48日龄)。不同日龄体长生长速率差异显著(P0.05)。耳石早期发育研究发现耳石长、耳石宽随鱼体的生长而增长,在17、19日龄之后其生长速率增大约2倍。采用分段回归方法分析耳石长、耳石宽与日龄的关系,发现二者异速生长的拐点均出现在19、20日龄,拐点前为慢速生长,之后为快速生长。研究发现凤鲚早期生长发育阶段的耳石形态有较为显著的改变:卵黄囊期、前弯曲期为圆形;弯曲期耳石长的生长大于耳石宽的生长,耳石逐渐变成椭圆形;耳石变成稳定形态后,耳石长宽比基本保持稳定。3.长江口凤鲚耳石微化学及其生活史初探为了解长江口凤鲚生活史特征,本文于2015年8月在长江口采集凤鲚样本。采用激光烧蚀联动的电感耦合等离子质谱仪(LA-ICP-MS)进行耳石锶和钙元素测定。定量线分析结果显示,长江口凤鲚具有两种不同生活史类型,一类具有明显的洄游习性,另一类洄游习性不明显。两类生活史类型既有特性又表现一定的共性。共性为早期都为半咸水生活;特性为一类生活史类型表现为较为复杂的生活史即具有洄游习性,其耳石锶钙比值表现为产卵、孵化时的半咸水生活习性以及生长发育时海水生活习性。另一类生活史类型表现为锶钙比值较平稳为7.00左右,反映出半咸水生活的习性,并未表现出洄游习性。这两种不同的生活史类型反映了凤鲚生长发育过程中的生存策略,这也说明长江口可能存在定居生活的凤鲚类型。本文旨在从耳石微化学探讨长江口凤鲚生活史类型,为今后凤鲚资源的保护利用以及人工养殖方面提供基础资料。
[Abstract]:Coilia Mystus, commonly known as anchovies, small anchovy, Clupeiformes, Engraulidae, and Anchovy (Coilia), mainly inhabits the estuaries and adjacent waters. The Yellow Bohai, the East China Sea and the South China Sea are distributed in China, and are the most important economic fish in the Yangtze Estuary. The resources of the anchovy in the estuary of the Yangtze River have come out because of the construction of water conservancy projects and environmental pollution. In order to better protect the resources of the anchovy, the age structure, the growth characteristics, the life history type and the growth and development of the young and juvenile fish are studied and discussed in this paper. The main results are as follows: 1. the age structure and growth characteristics of the breeding population of the anchovy in the Yangtze River Estuary in April 2014 ~8 month in the flourishing period of the anchovy at the mouth of the Yangtze River. The age structure and growth characteristics of female individuals in the breeding population of anchovy were studied. The age structure was 1~3 age and 3 age groups, of which the average body length and body weight of the 1~2 age group were 151.66 + 21.13mm, 16.97 + 6.34 g. body length and body weight (n=124, R2=0.9353). The significant difference test showed that the difference between the age group and the body weight was (n=124, R2=0.9353). The growth equation of body length and body weight von Bertalanffy is: the growth velocity curve of body length and body length has no turning point; the turning point of the body weight growth rate is 1.11 years old, the same as the minimum sexual age, and the corresponding body length and body weight at the turning point are 131.02 mm and 11.05 g., respectively. In order to make better use of and protect the resources of anchovy, the growth of archovy in the different developmental stages of.2. in the Changjiang Estuary should be grown in the main breeding period of the anchovy at Changjiang Estuary by 103 ind. to analyze the larvae and juveniles of anchovy anchovy in the main breeding period of the anchovy at Changjiang Estuary in the main breeding period of 2014 4~8. The fish samples showed that the age range was 5~48 D and the body length was between 4.20~26.21 mm. The growth of the early development of anchovy anchovy in the Yangtze Estuary was studied at different stages. The growth of the body length of the larvae and juveniles of anchovy (5~48 day age) was measured in 3 stages (5~11 days, 12~30 days, 31~48 days of age). The growth rate of the body length at different days of age was significant (P0.). 05. Early otolith development found that otolith was long, the width of otolith increased with the growth of the fish body, and the growth rate increased about 2 times after 17,19 days of age. The relationship between otolith length, otolith width and day age was analyzed by piecewise regression, and the inflexion points of the two speed growth were found at the age of 19,20, slow growth before the turning point, and then rapid birth. The study found that the otolith morphology of the early growth and development stages of the anchovy was significantly changed: the yolk sac period and the front bending period were round; the growth of otolith length in the bending period was larger than the otolith wide growth, the otolith gradually became oval; the otolith length and width ratio remained stable after the otolith was stable, and the microchemistry of the otolith of the.3. anchovy at the Yangtze Estuary was basically stable. In order to understand the life history of the anchovy in the Yangtze Estuary, this paper collected the samples of the anchovy in the Yangtze Estuary in August 2015. Using the inductively coupled plasma mass spectrometry (LA-ICP-MS) of laser ablation linkage, the strontium and calcium in the otolith were measured. The quantitative line analysis showed that the anchovy in the Yangtze Estuary had two different types of life history. There are obvious migratory habits and other types of migratory habits. The two types of life history have both characteristics and certain generality. The commonness is that the life history of the type of life history is a more complex life history, that is, the migratory habit, the ratio of strontium calcium in otolith is oviposition and the salty aquatic in hatching. The living habits and the living habits of sea water in the growth and development. The other type of life history is that the ratio of strontium calcium is more than 7, reflecting the habit of living in brackish water, and does not show the migratory habit. These two different types of life history reflect the survival strategy of the growth and development of the anchovy, which also indicates that the Yangtze Estuary may exist. The purpose of this paper is to explore the life history types of the anchovy in the Yangtze Estuary, and provide the basic information for the protection and utilization of the resources of the anchovy and the artificial culture in the future.
【学位授予单位】：上海海洋大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S917.4

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