共查询到19条相似文献，搜索用时 274 毫秒
1.
研究了卤虫无节幼体、专用仔鱼料、鳗鱼仔鱼料等3种不同饵料对西藏尖裸鲤(Oxygymnocypris stewartii)、异齿裂腹鱼(Schizothorax o'connori Lloyd)、拉萨裂腹鱼(Schizothorax waltoni Regan)等3种鱼类仔鱼生长和存活的影响。实验尖裸鲤、异齿裂腹鱼、拉萨裂腹鱼仔鱼的初始全长分别为(13.29±0.52)mm、(12.29±0.44)mm、(15.81±0.50)mm,实验周期分别为25 d、25 d、15 d。结果表明:与其他饵料组相比,投喂专用仔鱼料组,异齿裂腹鱼仔鱼和拉萨裂腹鱼仔鱼的平均全长、全长增加倍数以及存活率均高于其他各组,并有显著差异;尖裸鲤仔鱼的平均全长和全长增长倍数也高于其他各组,但存活率较投喂卤虫无节幼体低,并有显著差异。 相似文献
2.
采用不连续聚丙烯酰胺凝胶电泳技术对雅鲁藏布江中游6种裂腹鱼(尖裸鲤Oxygymnocypris stewartii、拉萨裸裂尻鱼Schizopygopsis younghusbandi、巨须裂腹鱼Schizothorax macropogon、拉萨裂腹鱼S.waltoni、双须叶须鱼Ptychobarbus dipogon和异齿裂腹鱼S.o'connori)的心肌、肌肉、肝脏、肾脏和晶状体5种组织的LDH(乳酸脱氢酶)同工酶进行比较分析。结果表明LDH同工酶的表达具有明显的组织和种间差异性。尖裸鲤、拉萨裸裂尻鱼和双须叶须鱼由LDH-A、LDH-B和LDH-B1基因编码,5种组织中分别检测到16、13和9条酶带;拉萨裂腹鱼和巨须裂腹鱼由LDH-A、LDH-B和LDH-C基因编码,5种组织中分别检测到9和6条酶带;异齿裂腹鱼由LDH-A和LDH-B基因编码,5种组织中检测到6条酶带。根据酶谱特征对其生物演化进行了探讨,发现尖裸鲤和拉萨裸裂尻鱼特化程度最高,其次是双须叶须鱼,巨须裂腹鱼、拉萨裂腹鱼和异齿裂腹鱼特化程度最低,与形态学特征所划分的三个类群吻合。 相似文献
3.
4.
西藏雅鲁藏布江中游裂腹鱼类优先保护等级定量评价 总被引：1，自引：0，他引：1
西藏地区雅鲁藏布江中游分布有6种特有裂腹鱼类,是地方重要的土著经济物种。近年来,受人类活动和环境变化的影响,裂腹鱼类资源已严重衰退而处于濒危,急需开展裂腹鱼类的资源现状调查及保护等级评价工作。本课题组分别于2015年和2017年的春季(4—5月),对雅鲁藏布江中游的渔业资源进行调查监测,参阅相关文献资料,采用珍稀性、物种价值和人为干扰共3个一级指标和5个二级指标建立优先保护等级的定量评价体系,对6种裂腹鱼类的资源状况及濒危状况进行评价,根据评分标准与优先保护综合评价值(R)确定裂腹鱼类的优先保护等级。研究结果表明,尖裸鲤(Oxygymnocypris stewartii)为一级优先保护鱼类,双须叶须鱼(Ptychobarbus dipogon)为二级优先保护鱼类,拉萨裂腹鱼(Schizothorax waltoni)和巨须裂腹鱼(Schizothorax macropogon)为三级优先保护鱼类,异齿裂腹鱼(Schizothorax o’connori)和拉萨裸裂尻鱼(Schizopygopsis younghusbandi)为四级优先保护鱼类。评价分级结果与实际情况相符,真实地反映了6种裂腹鱼类优先保护顺序。本研究对雅鲁藏布江中游的鱼类保护等级提出建议,为鱼类资源的科学保护管理等提供参考和依据。 相似文献
5.
2015年5月,在西藏雅鲁藏布江中游的桑日、朗县段水域开展鱼类调查,发现了1种疑似为拉萨裂腹鱼(Schizothorax waltoni)和异齿裂腹鱼(Schizothorax o’connori)的自然杂交种群体。形态学研究显示,该种的吻、口部、下颌、须等头部上的形态特征居于拉萨裂腹鱼和异齿裂腹鱼之间,并明显区别于双亲,且群体中个体的头部形态稳定一致,均具有典型的中间型特征,个体间没有明显差异。基于线粒体COI基因条形码分析显示,在杂交种群体共15个样本中,有4个与拉萨裂腹鱼为同源,其余11个与异齿裂腹鱼为同源,各自间的亲缘关系很近,即杂交种群体中既有属于拉萨裂腹鱼遗传基因的个体,也有属于异齿裂腹的遗传基因的个体。综合以上研究表明,拉萨裂腹鱼和异齿裂腹鱼在雅鲁藏布江中游的桑日等自然水域中能够自由杂交而产生后代,且两者都可以互为父母本,但以异齿裂腹鱼为母本产生的杂交种在群体中占多数,推测特殊的生态环境可能促使拉萨裂腹鱼和异齿裂腹鱼在自然水域中容易杂交。 相似文献
6.
针对裂腹鱼种类繁多、种间形态学差异不明显的特点,利用分子标记对高原裂腹鱼进行准确的物种鉴定具有重要价值。对采集的60尾高原裂腹鱼进行了COⅠ和16S rRNA基因的部分序列测定,并通过GenBank数据库进行鱼种鉴定;运用邻接法（NJ）构建系统发育树,对实验鱼进行群系划分;通过DNASP软件分析比较实验鱼COⅠ和16S rRNA基因的序列变异;依据MEGA 6.0的Kimura-2-parameter模型计算实验鱼的种内遗传距离和种间遗传距离,并对COⅠ和16S rRNA基因在高原裂腹鱼物种鉴定中的适用性进行探讨。结果表明,采集的样本包含3属、5种裂腹鱼,分别为尖裸鲤属的尖裸鲤（Oxygymnocypris stewartii）、裸鲤属的软刺裸鲤（Gymnocypris dobula）、裂腹鱼属的拉萨裂腹鱼（Schizothorax waltoni）、巨须裂腹鱼（Schizothorax macropogon）和异齿裂腹鱼（Schizothorax oconnori）。在COⅠ基因构建的系统发育树中,5种高原裂腹鱼均形成独立的一支,而16S rRNA基因不能准确地对裂腹鱼属的3个鱼种实现区分。研究显示,5种高原裂腹鱼COⅠ基因核苷酸的变异水平（Pi）和单倍型多样性指数（Hd）均高于16S rRNA基因;COⅠ基因计算得到实验鱼种间遗传距离和种内遗传距离平均值分别为0.025和0.002,种内和种间的最大遗传差异约为13倍;16S rRNA基因得出结果为0.026和0.005,而种内和种间的最大遗传差异约为6倍。综合COⅠ和16S rRNA基因能有效鉴定高原裂腹鱼物种,而在单个基因的选择上,COⅠ基因具有更高的适用性。 相似文献
7.
青海湖裸鲤与鲤、鲫、草鱼的随机扩增多态DNA分析 总被引：7，自引：0，他引：7
本文利用随机扩增多态DNA (RAPD)技术对 4种鲤科鱼类 ,即裂腹鱼亚科的青海湖裸鲤、鲤亚科的鲤和鲫鱼、雅罗鱼亚科的草鱼基因组DNA进行了分析 ,目的是探讨青海湖裸鲤的系统分类位置。遗传距离指数计算结果显示 ,鲤亚科 2个鱼种间的相似性显著高于青海湖裸鲤和草鱼间的相似性 ,而裂腹鱼亚科的青海湖裸鲤与另两个鲤亚科三种鱼类之间的差异 (0 876 9、 0 7145、 0 6 930 )明显高于雅罗鱼亚科草鱼与鲤亚科鲤、鲫鱼之间的差异 (0 4718、 0 5 2 18)。在此基础上讨论了RAPD技术适用性的一些问题 相似文献
8.
9.
青海湖裸鲤与鲤、鲫、草鱼的随机扩增多态DNA分析 总被引：3，自引：0，他引：3
本文利用随机扩增多态DNA(RAPD)技术对4 种鲤科鱼类,即裂腹鱼亚科的青海湖裸鲤、鲤亚科的鲤和鲫鱼、雅罗鱼亚科的草鱼基因组DN A进行了分析,目的是探讨青海湖裸鲤的系统分类位置.遗传距离指数计算结果显示,鲤亚科2个鱼种间的相似性显著高于青海湖裸鲤和草鱼间的相似性,而裂腹鱼亚科的青海湖裸鲤与另两个鲤亚科三种鱼类之间的差异(0.8769、0.7145、0.6930)明显高于雅罗鱼亚科草鱼与鲤亚科鲤、鲫鱼之间的差异(0.4718、0.5218).在此基础上讨论了RAPD技术适用性的一些问题. 相似文献
10.
本试验旨在探索3种西藏土著鱼类幼鱼水温耐受性。试验鱼初始饲养水温为12℃。选用拉萨裸裂尻鱼(3月龄)、异齿裂腹鱼(2月龄)、双须叶须鱼(3月龄)各90尾,各分为3个试验组,每个试验组设3个平行,每个平行10尾鱼。其中,2个试验组为升温、降温试验,1组为对照。通过每1h上升或者下降1℃,适应3h,观察并记录每个温度下试验鱼的死亡率、摄食情况、活动情况及鳃呼吸频率等。试验结果表明,拉萨裸裂尻鱼幼鱼、异齿裂腹鱼幼鱼和双须叶须鱼幼鱼摄食水温分别为8～27℃、8～25℃和7～26℃;温度过高,3种试验鱼均表现出侧游,呼吸急促,反应急躁;温度过低,试验鱼不摄食,不活动,呼吸微弱。极限最高温度分别为32.3、32.4℃和30.2℃,极限最低温度分别为0、0.4℃和0℃。温度耐受幅分别为32.3、32℃和30.2℃。因此,这3种西藏土著鱼类温度耐受幅较广,以温度为指标,可选择较多区域进行养殖。 相似文献
11.
嵊泗人工鱼礁海区生态系统能量流动模型初探 总被引：6，自引：1，他引：6
主要根据从2005年1月开始投放人工鱼礁至11月在嵊泗人工鱼礁海区进行的环境、资源和生态调查资料,应用Ecopath withEcosim(EwE)软件,构建嵊泗人工鱼礁海区生态系统初步能量流动模型。模型由13个功能组构成,每一组都代表在生态系统中具有相似地位的有机体,基本覆盖了嵊泗人工鱼礁海区生态系统能量流动的主要过程。模型分析表明,嵊泗人工鱼礁海区生态系统的能量流动主要以捕食食物链途径为主,各功能组的营养级范围为1.00~4.18。生态网络分析表明,系统的能量流动主要有6级,来自初级生产者的能流效率为13.8%,来自碎屑的转换效率为13.4%,平均能量转换效率为13.6%。 相似文献
12.
In subarctic lake systems, fish species like brown trout are often important predators, and their niche performance is a key characteristic for understanding trophic interactions and food web functioning at upper trophic levels. Here, we studied summer habitat use and stomach contents of brown trout under both allopatric and sympatric conditions in six subarctic lakes to reveal its trophic role, and population‐ and individual‐level niche plasticity. In allopatry, brown trout mainly used the littoral habitat, but also less commonly used the pelagic zone. In sympatry with stickleback, there was always a considerable habitat overlap between the two species. In contrast, sympatric populations of brown trout and Arctic charr generally revealed a distinct habitat segregation. In the sympatric systems, in general, there was a distinct resource partitioning between the trout and charr, whereas the observed diet overlap between trout and stickleback was much larger. Trout modified their individual dietary specialisation between the littoral and pelagic zone, always being lower in the pelagic. Piscivorous behaviour of trout was only found in sympatric systems, possibly contributing to a competitive advantage of trout over charr and stickleback. Hence, the trophic level of trout was strongly related to the fish community composition, with a higher trophic level in sympatric systems where piscivorous behaviour was frequent. These changes in the trophic level of trout linked with the observed food resource partitioning might be an important mechanism in the ecosystem functioning of subarctic lakes to allow coexistence among sympatric‐living fish species. 相似文献
13.
尖裸鲤(Oxygymnocypris stewartii)成熟卵呈圆形,黄色,沉性,卵径(2.57±0.07)mm,受精卵吸水充分膨胀后卵径为(3.22±0.07)mm。水温9.5～11.8℃,尖裸鲤胚胎发育历时265h,根据胚胎发育的外部形态及典型特征,将其分为受精卵、胚盘形成、卵裂、囊胚、原肠、神经胚、器官分化和孵化共8个阶段、32个时期。出膜仔鱼全长(10.27±0.15)mm,出膜20d后卵黄耗尽,全长(15.22±0.27)mm。出膜后80d,鱼苗全长(23.65±0.59)mm,臀鳞出现,各鳍均已出现,鱼苗侧线全部形成且清晰,体色和体型接近成鱼。尖裸鲤早期发育的特点反映了其对雅鲁藏布江水域的适应性。报道了尖裸鲤胚胎发育和仔稚鱼发育的生物学特性,为雅鲁藏布江特有鱼类资源保护利用提供科学依据和理论基础。 相似文献
14.
本研究通过对2011~2014年间在黄海及东海北部采集的36种海洋鱼类进行碳、氮稳定同位素测定,利用碳稳定同位素比值(δ13C)计算底层饵料贡献比(Bp)来确定鱼类的食性,利用氮稳定同位素比值(δ15N)计算其营养级(TL)。结果显示,这36种鱼类的营养级范围为2.75~4.34,平均值为3.47。其中,4种为完全浮游生物食性,8种为底栖生物食性,完全底栖生物食性为12种,混合食性为12种。中(TL=3.5~4)、低(TL<3.5)营养级的种类占大多数(91.67%),而高营养级(TL>4)种类较少,仅为3种,且全部为混合食性。营养级的研究结果与1986、1992和2004年的研究对比发现,个别种类发生了改变。如蓝点马鲛(Sconberonorus niphonius)营养级有不同程度的下降;而黄鲫(Setipinna t)aty却有不同程度的上升。食性的研究结果与2004、2009和2011年的研究对比发现,有些种类食性发生了较大变化,如白姑鱼(Argyrosomus argentatus);有些种类食性几乎没有变化,如小黄鱼(Larimichthys polyactis)。 相似文献
15.
中国水产养殖种类组成、不投饵率和营养级 总被引：6，自引：1，他引：5
根据1950–2014年水产养殖种(类)有关统计和调研数据,并在对养殖投饵率、饲料中鱼粉鱼油比例、各类饵料(配合饲料、鲜杂鱼/低值贝类/活鱼、天然饵料等)营养级等基本参数进行估算的基础上,研究分析了中国水产养殖种类组成、生物多样性、不投饵率和营养级的特点及其变化。结果表明:中国水产养殖结构相对稳定,变化较小,其显著特点是种类多样性丰富、优势种显著、营养层次多、营养级低、生态效率高、生物量产出多。其中:(1)养殖种类296个、品种143个,合计为439个。种类组成区域差异明显,淡水养殖鱼类占绝对优势,如2014年草鱼、鲢鱼、鳙鱼、鲤鱼、鲫鱼和罗非鱼排名前6个种类的养殖占淡水养殖产量69.6%,其次为甲壳类、其他类、贝类及藻类,而海水养殖则以贝藻类为主,如2014年牡蛎、蛤、扇贝、海带、贻贝和蛏6个种(类)的养殖占海水养殖产量71.3%,其次为甲壳类、鱼类及其他类;(2)养殖种类多样性特征显著,与世界其他主要水产养殖国家相比,独为一支,具较高的多样性、丰富度和均匀度,发展态势良好;(3)由于养殖方式从天然养殖向投饵养殖转变,不投饵率呈明显下降趋势,从1995年90.5%降至2014年53.8%(淡水35.7%,海水83.0%),但与世界平均水平相比,仍保持较高的水准;(4)与世界相比,营养级低且较稳定。由于配合饲料的广泛使用及其鱼粉鱼油使用量减少,近年营养级略有下降,从2005年较高的2.32降至2014年2.25(淡水2.35,海水2.10)。营养级金字塔由4级构成,以营养级2为主,近年占70%,表明其生态系统有较多的生物量产出。中国水产养殖未来发展需要遵循绿色、可持续和环境友好的发展理念,探讨适宜的、特点各异的新生产模式,发展以养殖容量为基础的生态系统水平的水产养殖管理,建设环境友好型的水产养殖业,为保障国家食物安全、促进生态文明建设作出更大贡献。 相似文献
16.
Gallagher CP, Dick TA. Trophic structure of a landlocked Arctic char Salvelinus alpinus population from southern Baffin Island, Canada. Ecology of Freshwater Fish 2010: 19: 39–50. © 2009 John Wiley & Sons A/S
Abstract – Stable isotopes, diet and parasites were used to investigate the trophic structure of landlocked Arctic char ( Salvelinus alpinus ) from a small Canadian Arctic lake. Two trophic levels of char were identified. The lower trophic level comprised smaller char that consumed mainly invertebrates and harboured low numbers of the cestode plerocercoid Diphyllobothrium spp. while the higher trophic level char were larger, mainly piscivorous and had high numbers of plerocercoids. Procercoids of Diphyllobothrium spp. in copepods are eaten by char where the parasite then differentiates into a plerocercoid. Plerocercoids from smaller fish are transmitted to larger fish by piscivory where they encyst again as plerocercoids until the fish is eaten by a gull. These plerocercoids are a good indicator of trophic level as their numbers accumulate over time in larger fish. The three variables together provided a better resolution of trophic structure than applied separately. For example, plerocercoid numbers plus diet were better predictors of trophic status than stable isotopes in 4–7 year olds, but for char ≥8 years all three variables were complementary. Some char (≥10 years old) were placed in the lower trophic level based on their stable isotope values and had low Diphyllobothrium spp. abundance but were piscivorous and/or cannibalistic. The absence of sexually mature char in the higher trophic group was associated with high numbers of Diphyllobothrium spp. plerocercoids. 相似文献
Abstract – Stable isotopes, diet and parasites were used to investigate the trophic structure of landlocked Arctic char ( Salvelinus alpinus ) from a small Canadian Arctic lake. Two trophic levels of char were identified. The lower trophic level comprised smaller char that consumed mainly invertebrates and harboured low numbers of the cestode plerocercoid Diphyllobothrium spp. while the higher trophic level char were larger, mainly piscivorous and had high numbers of plerocercoids. Procercoids of Diphyllobothrium spp. in copepods are eaten by char where the parasite then differentiates into a plerocercoid. Plerocercoids from smaller fish are transmitted to larger fish by piscivory where they encyst again as plerocercoids until the fish is eaten by a gull. These plerocercoids are a good indicator of trophic level as their numbers accumulate over time in larger fish. The three variables together provided a better resolution of trophic structure than applied separately. For example, plerocercoid numbers plus diet were better predictors of trophic status than stable isotopes in 4–7 year olds, but for char ≥8 years all three variables were complementary. Some char (≥10 years old) were placed in the lower trophic level based on their stable isotope values and had low Diphyllobothrium spp. abundance but were piscivorous and/or cannibalistic. The absence of sexually mature char in the higher trophic group was associated with high numbers of Diphyllobothrium spp. plerocercoids. 相似文献
17.
分析了松花江哈尔滨段宾县石场和鸟河乡两个采样点水域野生花（Hemibarbus maculatus）、麦穗鱼（Pseudorasbora parva）、条纹似白鮈（Paraleucogobio strigatus）等三种鮈亚科鱼类消化道食物的组成,研究了这三种鱼类在河流生境下食性类型、营养级,探讨其在特定生态系统中饵料基础及鱼类间食物关系。结果表明,花属杂食性,主要摄食水生昆虫、底栖生物、浮游植物,营养级为3.86;麦穗鱼为杂食性,其食物组成为小鱼、水生昆虫、浮游动物、浮游植物,营养级为3.07级。条纹似白鮈属底栖动物食性,主要摄食水生昆虫,营养级为2.53。 相似文献
18.
The integrated multi‐trophic aquaculture (IMTA) is a semi‐artificial habitat optimization ecosystem by co‐culture species from multiple trophic levels, in which farm waste produced by species of a higher trophic level is a nutrition source for species of a lower trophic level. However, in system construction it is essential to distinguish the roles of aquaculture organisms from different trophic levels and optimize the aquaculture capacity allocation. With this objective, a carrying capacity evaluation model for shrimp culture with integrated bioremediation techniques was developed, and the efficiency to repair the aquaculture pond environment was evaluated. Scenario simulations were conducted to assess the shrimp culture capacity for optimal economic and ecological benefits. The sensitivity analysis of the model indicated that changes in bivalve biomass had no significant impacts on the concentration of total nitrogen (TN) in the system, and macroalgae were more sensitive to the changes in TN than biofilters did. In conclusion, 1,500,000 Litopenaeus vannamei co‐cultured with 15,000 kg Crassostrea gigas and 1,125 kg Gracilaria lemaneiformis per hectare would bring maximum integrated benefit, and the use of integrated bioremediation techniques can make shrimp pond culture a virtuous cycle incorporating both production and restoration. 相似文献
19.
Contrasting changes in freshwater fish assemblages and food webs follow modification of tropical waterways 
下载免费PDF全文
下载免费PDF全文 Jia Huan Liew Xingli Giam Esther Clews Kenrick Y. W. Tan Heok Hui Tan Zi Yi Kho Darren C. J. Yeo 《Ecology of Freshwater Fish》2018,27(4):1114-1125
Fresh waters are increasingly threatened by flow modification. Knowledge about the impacts of flow modification is incomplete, especially in the tropics where ecological studies are only starting to emerge in recent years. Using presence/absence data dated approximately four decades apart (~1966 to ~2010) from 10 tropical rivers, we assessed the changes in freshwater fish assemblage and food web after flow modification. The sites were surveyed with methods best suited to habitat conditions (e.g., tray/push netting for low‐order forest streams, visual surveys for canalised rivers and net casting for impounded rivers). With the presence/absence data, we derived and compared six measures of fish assemblage and food web structure: species richness, proportion of native species, overall functional diversity, native functional diversity, food web complexity and maximum trophic level. We found that changes in community assemblage and food web structure were not generalisable across modification regimes. In canalised sites, species richness and maximum trophic levels were lower in the second time period while the opposite was true for impounded sites. However, proportion of native species was consistently lower in the second time period across modification regimes. Changes in fish assemblages and food webs appear to be driven by species turnover. We recorded 79 cases of site‐specific extirpation and 117 cases of site‐specific establishment. Our data further suggest that turnover in assemblage is again contingent on flow‐modification regime. While the process was stochastic in canalised rivers, benthopelagic species were more likely to be extirpated from impounded rivers where species lost were replaced by predominantly alien fish taxa. 相似文献