基于氮稳定同位素分析的三峡水库主要鱼类营养级研究  

Trophic Level of Major Fish Species in the Three Gorges Reservoir Based on Nitrogen Stable Isotope Analysis

作　　者：何春 邓华堂[2] 王果[1] 刘寒文[2] 沈子伟[2] 刘绍平[2] 段辛斌[2] 陈大庆[2] 李云[1] HE Chun;DENG Huatang;WANG Guo;LIU Hanwen;SHEN Ziwei;LIU Shaoping;DUAN Xinbin;CHEN Daqing;LI Yun(Institute of Three Gorges Ecological Fisheries of Chongqing,College of Fisheries,Southwest University,Chongqing 400715,China;Fishery Resources and Environmental Science Experimental Station of the Upper-Middle Reaches of Yangtze River,Ministry of Agriculture and Rural Affairs,Yangtze River Fisheries Research Institute,Chinese Academy of Fishery Science,Wuhan,Hubei 430223,China)

机构地区：[1]西南大学水产学院重庆三峡生态渔业产业技术研究院,重庆400715 [2]中国水产科学研究院长江水产研究所农业农村部长江中上游渔业资源环境科学观测实验站,湖北武汉430223

出　　处：《渔业科学进展》2022年第4期116-126,共11页Progress in Fishery Sciences

基　　金：国家自然科学基金项目(51909271);中央高校基本科研业务费专项(2362020-2020jd002);农业农村部长江中上游渔业资源环境科学观测实验站开放课题(FRESES201905);中国水产科学研究院创新团队项目(2020TD09)共同资助。

摘　　要：运用稳定同位素技术对2018年7月—2019年1月采自三峡库区干流木洞、涪陵、云阳和秭归江段的38种鱼类进行氮稳定同位素分析,同时计算鱼类营养级并构建了鱼类连续营养谱。研究结果显示,三峡库区干流鱼类δ^(15)N值平均值为11.02‰,变化范围为5.31‰~17.79‰。以初级消费者螺类作为基准生物估算出三峡库区干流鱼类平均营养级为2.67,范围为1.47~4.12。营养级大于4级的鱼类仅有1种,营养级位于2~3级之间的鱼类种类数最多,占种类总数的50.0%,其次是营养级大于3级的鱼类,占种类总数的31.6%,不同食性鱼类组合的营养级存在差异。库区干流鱼类营养级的时空差异均不显著,而越靠近大坝的江段食物链长度的季节性波动幅度越大。和水库蓄水运行初期相比,鱼类营养级显著升高且高营养级鱼类的群落结构和营养特征发生了一定程度的改变,特别是拥有较高营养级的短颌鲚(Coilia brachygnathus)在库区干流逐渐扩张并成为优势种,其可能对库区干流鱼类营养结构产生影响。Trophic level,a basic and measurable feature in complex food networks,represents the position of organisms in the ecosystem and reflects the vertical structure of the food web.The study of trophic levels is used to interpret sophisticated ecological relationships through simplified functional groups and is of great significance to the construction of ecosystem models and the study of nutrient cycling.The construction of the Three Gorges Dam and the operation of the reservoir have fragmented the river ecosystem.The influences of reservoir storage and operation vary between river sections with disparate geomorphic characteristics.Environmental heterogeneity may cause temporal and spatial variation in the structure of the fish community of each section of the mainstream from the reservoir.After two decades,research on fish trophic levels has mainly focused on the initial stage of storage and operation of the reservoir,while information on the fish trophic level in the mainstream remains scarce.To evaluate the long-term spatiotemporal variation in fish trophic levels in the Three Gorges Reservoir,nitrogen stable isotopes of 38 fish species and three snail species were collected from the Mudong,Fuling,Yunyang,and Zigui river sections of the main stream of the Three Gorges Reservoir from July 2018 to January 2019,and the continuous spectra of fish species trophic levels in the reservoir were constructed based on stable isotope analysis.The results showed that the averageδ15N value of snails was 8.37‰,ranging from 8.29‰to 8.53‰,and there was no significant spatial difference between the river sections.Except for the Mudong section,theδ15N values of snails in the other river sections were significantly higher in the flood season than in the dry season.Nitrogen stable isotope analysis of fish samples showed that the average value ranged from 5.31‰to 17.79‰,with an average of 11.02‰.Taking snails as the baseline organism,fish trophic levels were calculated for each river section according to season,and the re

关 键 词：鱼类 稳定同位素 三峡库区 营养级 连续营养谱 

分 类 号：S932[农业科学—渔业资源]