Page 119 - 《水产学报》2025年第6期

张玉凤，等 水产学报, 2025, 49(6): 069309

Spatial patterns of fish diversity in the Chongqing section of
the Yangtze River Basin based on eDNA

ZHANG Yufeng , ZHOU Xinxin , LI Qinghua , ZHANG Jiaming , SHEN Yanjun *
Laboratory of Water Ecological Health and Environmental Safety, College of Life Sciences,
Chongqing Normal University, Chongqing 401331, China

Abstract: Fish diversity not only plays a pivotal role in maintaining the balance and stability of aquatic ecosystems, but also
serves as a critical indicator for assessing the health status of freshwater ecosystems. However, prolonged anthropogenic dis-
turbances, including hydraulic development, environmental pollution, and the introduction of exotic fish species, have resulted
in varying degrees of habitat degradation for ichthyofauna in the Chongqing section of the Yangtze River Basin, posing severe
threats to contemporary fish biodiversity. This study aimed to investigate the current status and spatial pattern evolution of fish
diversity in the Chongqing section of the Yangtze River Basin following reservoir impoundment. From May to June 2022,
environmental DNA (eDNA) technology was employed to survey fish diversity across six mainstream sections (from Jiangjin
to Wushan) and eight important primary tributary sections. A total of 107 fish species were detected, belonging to 7 orders, 20
families, and 74 genera. These included 6 nationally protected species, 17 endemic species to the upper Yangtze River, and 12
exotic species. Comparative analysis of post-impoundment periods revealed an increase in exotic species compared to the trial
operation phase of the Three Gorges Reservoir. Notably, the proportion of rheophilic fish species declined, while eurytopic fish
species increased. Tributary habitats exhibited higher alpha diversity indices than adjacent mainstream sections. The grouping
model demonstrated that the Jiangjin-Fuling section had a higher average alpha diversity index than the Fuling-Wushan section,
with statistically significant differences in fish community composition between the groups. This study elucidates the current
status and spatial pattern evolution of fish diversity in the Chongqing section of the Yangtze River Basin. It further validates the
feasibility and efficiency of eDNA technology for fish diversity monitoring, positioning it as a robust complement to traditional
survey methods.
Key words: fish diversity; exotic fishes; environmental DNA (eDNA); the Three Gorges Reservoir area
Corresponding author: SHEN Yanjun. E-mail: shenyanjun@cqnu.edu.cn

Funding projects: National Natural Science Foundation of China (32202939); Chongqing Aquatic Science and Technology
Innovation Union Key Innovation Research Project (CQFTIU-20220101); Chongqing Natural Science Foundation
(CSTB2022NSCQ-MSX0793)

https://www.china-fishery.cn 中国水产学会主办 sponsored by China Society of Fisheries
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