| 摘要: |
| 本研究应用碳、氮稳定同位素技术分析了2017年秋季（10月）和2018年春季（3月）湖北省荆州长湖鱼类营养结构特征，构建了δ13C和δ15N稳定同位素双位图，并计算了7个相关的量化指标。结果显示：所采集的16种鱼类，δ13C均值范围为（-27.7±0.8）‰~（-24.8±0.1）‰，δ15N的均值范围为（11.4±0.3）‰~（16.6±0.5）‰。营养生态位分析显示，长湖鱼类以偏肉食性鱼类黄颡鱼的营养级最高（3.28±0.2），草鱼的营养级最低（1.74±0.1）。稳定同位素的量化指标表明，长湖春季鱼类群落核心生态位空间（standard ellipse area， SEA）、生态位总空间（total area， TA）和基础食物来源（δ13C range， CR）均高于秋季，两个季度的营养多样性（centrifugal distance， CD）和鱼类群落的整体密度（mean nearest neighbor distance， MNND）相似，但春季的营养长度（δ15N range， NR）和鱼类群落营养生态位分布范围（standard deviation of nearest neighbor distance， SDNND）值低于秋季。说明春季长湖的生态位总空间（TA上升）和基础食物来源（CR上升）较为丰富，但因鱼类种类的食性相近，其群落的总食物链降低（NR下降）。该研究可为分析拆围后长湖鱼类群落结构特征积累基础数据，也为长湖的渔业管理策略提供依据。 |
| 关键词: 鱼类 稳定同位素 长湖 营养结构 |
| DOI：10.14188/j.ajsh.2021.06.002 |
| 分类号:S932.4 |
| 基金项目:国家重点研发计划项目（2019YFD0900603）；院级基本科研业务经费（2020TD57）和现代农业产业技术体系专项资金（CARS-46） |
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| Study on trophic structure of fish communities in Changhu Lake based on stable carbon and nitrogen isotopes |
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LI Xuemei, ZHU Tingbing, WANG Xuge, HE Yongfeng, YANG Deguo
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Key Laboratory of Freshwater Biodiversity Conservation， Ministry of Agriculture and Rural Affairs of China Yangtze River Fisheries Research Institute， Chinese Academy of Fishery Sciences， Wuhan 430223， Hubei， China
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| Abstract: |
| In this study， stable carbon and nitrogen isotope techniques were used to analyze the characteristics of fish community structure in Changhu Lake in autumn （October 2017） and spring （March 2018）， and the quantitative metrics were caculated based on δ13C and δ15N bitmaps. Sixteen fish species were collected and the mean value of δ13C ranged from （-27.7±0.8）‰ to （-24.8±0.1）‰， and the δ15N values ranged from （11.4±0.3）‰ to （16.6±0.5）‰. According to the δ15N values， Pelteobagrus fulvidraco showed the highest trophic level （3.28±0.2）， while Ctenopharyngodon idellus showed the lowest （1.74±0.1）. The quantitative metrics revealed that standard ellipse area （SEA）， total area （TA） and δ13C range （CR） of fish communities in spring were higher than those in autumn， and the average centrifugal distance （CD） and mean nearest neighbor distance （MNND） were similar between two seasons， while δ15N range （NR） and standard deviation of nearest neighbor distance （SDNND） were higher in autumn. The result indicated that the total niche space （TA rising） and basic food source （CR rising） were more abundant in spring， but the food chain （NR decreasing） of fish community decreased due to the similar feeding habits of fish species in Changhu Lake. The study could accumulate basic data for the characteristics of fish community and provide basis for fishery management strategy after removing the pen culture in Changhu Lake. |
| Key words: fish species stable isotope Changhu Lake trophic structure |
