【作者】 马宝珊；

【导师】 谢从新；

【作者基本信息】 华中农业大学 ， 水生生物学， 2011， 博士

【摘要】 异齿裂腹鱼(Schizothorax o’connori)属鲤形目(Cypriniformes),鲤科(Cyprinidae),裂腹鱼亚科(Schizothoracinae),裂腹鱼属(Schizothorax),为我国特有种,仅分布于西藏雅鲁藏布江中上游干支流及附属水体。于2008年8月至2009年8月,在雅鲁藏布江拉孜至尼木江段(占样本量的98.9%)及其支流香曲和年楚河,采集异齿裂腹鱼1126尾,并对谢通门江段的水生生物进行了初步调查。根据对采集样本测定分析,研究了异齿裂腹鱼的生物学特性及其种群动态。论文主要结果如下：1.耳石、脊椎骨和鳃盖骨均呈现出宽带和窄带相间的典型年轮特征。三种年龄材料的年轮形成于每年的3-5月份。耳石上的年轮最为清晰。脊椎骨和鳃盖骨与耳石之间的IAPE分别为9.3%和11.4%；低于21龄时,各龄鱼脊椎骨与耳石之间的IAPE较小,脊椎骨的年轮读数与耳石未见显著性差异(p>0.05)。相比较而言,耳石是异齿裂腹鱼年龄鉴定的最合适材料,脊椎骨次之,鳃盖骨最差。2.渔获物体长范围为33～553mm,体重范围为0.6～2982.6g,年龄组成为1～50龄,雌鱼和雄鱼的最大年龄分别为50龄和40龄。体长体重的关系式为W=2.034×10-5SL2.940,丰满度和含脂量随月份有显著性变化。耳石规格(长度、宽度和重量)与体长的相关性比年龄要高。von Bertalanffy生长方程：雌鱼：Lt=576.9(1-e(-0.081)(t +0.946)),Wt=2666.2(1-e-0.081(t+0.946))2.94；雄鱼：Lt=499.7(1-e-0.095(t+0.896)),Wt= 1748.1(1-e-0.095(t+0.896))2.94。雌鱼和雄鱼生长拐点分别为12.4龄和10.5龄。3.本次调查共检出浮游植物6门74属,浮游动物3门46属,周丛生物12门104属,底栖动物5门28属或科,鱼类3目5科14属。浮游植物和浮游动物的密度和生物量以秋季最高；周丛生物的密度和生物量以春季最高,夏季最低；而底栖动物的密度以秋季最高,但生物量却以春季为高。浮游植物的Shannon-Wiener多样性指数(H’)和Pielou均匀性指数(J)以春季最高,周丛生物和底栖动物以夏季最高。其中,周丛生物以硅藻最多,底栖动物以摇蚊幼虫最多。4.异齿裂腹鱼摄食强度随月份和体长变化差异显著。异齿裂腹鱼主要以硅藻、绿藻、蓝藻、其他藻类、小型无脊椎动物、大型无脊椎动物为食；无论是从出现率、个数百分比、重量百分比还是相对重要性百分比来看,硅藻都是比例最高的一类。不同季节、不同体长和不同性别的食物组成多样性(H’)和均匀性(J)有所差别。Amundsen图表明异齿裂腹鱼是广食性鱼类,不同个体间的食物组成差异较小。不同季节的食物组成存在显著性差异,而不同体长和不同性别的食物组成重叠程度较高。异齿裂腹鱼以附着在岩石上的周丛生物为食(主要成分为硅藻)。异齿裂腹鱼摄食消化器官的形态与其食性相适应。5.在繁殖季节,成熟雄性吻端、眼眶周围、各鳍鳍条分布珠星。异齿裂腹鱼种群雌雄比为1.20：1,与1：1存在显著性差异。初次性成熟的雌鱼体长为433.Omm,体重为1147.16g,年龄为16.2龄；初次性成熟的雄鱼体长为359.4mm,体重为663.36g,年龄为12.5龄。从不同月份不同性腺发育期所占比例、不同月份的性体指数变化以及不同月份卵径分布图,可以看出,异齿裂腹鱼属于同步产卵类型,并且繁殖期较短,集中于2-4月份。绝对繁殖力为8228-39343(21190±6990)粒,相对繁殖力为7.0-25.8(16.8±3.9)粒/g。异齿裂腹鱼绝对繁殖力随着体长和体重的增加呈增加趋势,但与年龄无显著相关性。6.异齿裂腹鱼的总死亡系数(Z)雌性为0.09/年,雄性为0.11/年；自然死亡系数(M)雌雄分别为0.05/年和0.06/年；捕捞死亡系数(F)雌雄分别为0.04/年和0.05/年；开发率雌雄分别为0.44/年和0.45/年。以达氏鳇(Huso dauncus)和尖头塘鳢(Eleotris oxycephaoa)作为参照物,表明异齿裂腹鱼属比较典型的k-选择类型鱼类。通过单位补充量亲鱼生物量模型分析,显示目前雅鲁藏布江谢通门至尼木江段的异齿裂腹鱼种群资源的开发水平较为合理。更多还原

【Abstract】 Schizothorax o’connori belongs to genus Schizothorax, subfamily Schizothoracinae, family Cyprinidae, order Cypriniformes. Schizothorax o’connori is the unique species in China, which distribute in the upper and middle reaches of the Yarlung Tsangpo River and its tributaries. In total,1126 S. o’connori individuals were collected from the Yarlung Tsangpo River (98.9%) and its tributaries (Xiang Qu and Nyang Qu) monthly from August 2008 to August 2009. Biology and population ecology of S. o’connori were studied. The aquatic organisms in Xaitongmoin reach of the Yarlung Tsangpo River were also investigated. The main results are as follows:1. Otoliths, vertebrae and opercular bones of S. o’connori showed the typical pattern with translucent zones that alternated with opaque zones. Annuli formed between March and May once a year in all of the three calcified structures. Annuli on otoliths were clearer than others. The IAPE value of vertebra vs. otolith was 9.3%, while that of opercular bones vs. otolith was 11.4%. For age classes 1-21, The IAPE values of vertebra vs. otolith were almost below 11%, and mean values of age estimates from different structures showed no significantly difference (p>0.05) between otolith and vertebra. Otolith was the most accurate structure for age estimation of S. o’connori, followed by vertebra and opercular bone.2. The standard length (SL) of S. o’connori ranged 33-553 mm, weight (W) ranged 0.6-2982.6 g, the estimated age range varied from 1 to 50. The maximum age observed was 50 years for females and 40 years for males. Length-weight relationship was described as W=2.034×10-5 SL2.940. Fullness and Coefficient of fat differed monthly. The correlations of otolith dimensions (length, breadth, and weight) and fish length were higher than those of age. The von Bertalanffy growth function were:Lt=499.7 (1-e-0.095 (t+0.896)) and Wt=2666.2 (1-e-0.081(t+0.946))2.94 for females, and Lt=576.9 (1-e-0.081 (t+ 0.946)) and Wt=1748.1 (1-e-0.095(t+0.896))2.94 for males. The inflexion point for the growth of female and male were 12.4 and 10.5 years, respectively.3.74 genera,6 phyla of phytoplankton,46 genera,3 phyla of zooplankton,104 genera, 12 phyla of periphyton,28 genera or family,12 phyla of zoobenthos were observed in this investigation. The density and biomass of phytoplankton and zooplankton were highest in Autumn, while those of periphyton were highest and lowest in Spring and summer. And density and biomass of zoobenthos were highest in Autumn and Spring, respectively. Shannon-Wiener index (H) and Pielou’s evenness index (J) of phytoplankton were highest in Spring, while those of periphyton and zoobenthos were highest in Summer. The most item in periphyton was diatoms, and the most item in zoobenthos was Chironomida larvae.4. The ingest intension varied significantly over month and length classes (p<0.05). S. o’connori fed on diatoms, green algae, cyanophytes, other algae, small invertebrates, and macroinvertebrates. Diatoms was the most important food, in term of number, weight and relative importance. Some differences were observed in Feeding diversity (H) and evenness (J) over season and fish size. The Amundsen figure indicated that S. o’connori was a generalized feeder with high diet overlap within individuals. Diet composition was relatively heterogenous among seasonal groups, while high degrees of diet overlap were found for prey composition among fish length and sexes.. S. o’connori grazes periphyton (mainly diatoms) attached to rocks, and the shape of digestive organ corresponding to its feeding habits.5. There are pearl organs on rostral side, orbit vicinity and fin rays of males in spawning season. The female and male ratio was 1.20:1, which differed significantly from 1:1. Standard length, weight and age of the females at first maturity were 433.0 mm, 1147.16 g and 16.2 years, respectively, and those of the males were 359.4 mm,663.36 g and 12.5 years, respectively. According to macroscopic stage of gonads, gonadosomatic index (GSI) and the size distribution of oocytes over month, S. o’connori were single spawners with a short-term spawning pattern during February and April. The fecundity ranged 8228-39343 (21190±6990) eggs, and the relative fecundity ranged 7.0-25.8 (16.8±3.9)/g body weight. The fecundity increased with standard length and body weight, but had no significant correlations with ages.6. The total mortality was 0.09/year for females and 0.11/year for males. Natural mortality was 0.05/year for females and 0.06/year for males, and fishing mortality was 0.04/year for females and 0.05/year for males. Exploitation level of S. o’connori was 0.44/year for females and 0.45/year for males. Took Huso dauncus and Eleotris oxycephaoa as reference, the life history pattern of S. o’connori belonged to k-selection. Assessing the stock status using the spawning stock biomass per recruit model, we concluded that the resource of S. o’connori had already been fished proporly in the Yarlung Tsangpo River.更多还原