Short-term responses of macroinvertebrate assemblages to the "ten-year fishing ban" in the largest highland lake of the Yangtze basin

Lu Yang; Min Pan; Jingrui Sun; Yongde Cui; Jinyan Dong; Jiaojiao Yang; Songhao Ji; Juan Tao; Chengzhi Ding

doi:10.1016/j.jenvman.2023.118160

Short-term responses of macroinvertebrate assemblages to the "ten-year fishing ban" in the largest highland lake of the Yangtze basin

J Environ Manage. 2023 Oct 1:343:118160. doi: 10.1016/j.jenvman.2023.118160. Epub 2023 May 23.

Authors

Lu Yang¹, Min Pan², Jingrui Sun¹, Yongde Cui³, Jinyan Dong⁴, Jiaojiao Yang⁴, Songhao Ji¹, Juan Tao¹, Chengzhi Ding⁵

Affiliations

¹ Yunnan Key Laboratory of International Rivers and Transboundary Eco-security, Yunnan University, Kunming, 650091, China; Institute of International Rivers and Eco-security, Yunnan University, Kunming, 650091, China.
² Kunming Dianchi and Plateau Lakes Institute, Kunming, 650228, China; Dianchi Lake Ecosystem Observation and Research Station of Yunnan Province, Kunming, 650228, China. Electronic address: panmin333@foxmail.com.
³ State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.
⁴ Kunming Dianchi and Plateau Lakes Institute, Kunming, 650228, China; Dianchi Lake Ecosystem Observation and Research Station of Yunnan Province, Kunming, 650228, China.
⁵ Yunnan Key Laboratory of International Rivers and Transboundary Eco-security, Yunnan University, Kunming, 650091, China; Institute of International Rivers and Eco-security, Yunnan University, Kunming, 650091, China. Electronic address: chzhding@ynu.edu.cn.

PMID: 37229854
DOI: 10.1016/j.jenvman.2023.118160

Abstract

The rapid decline of freshwater biodiversity caused by overfishing has led to the implementation of a series of conservation measures, including fishing bans. However, existing studies have mostly focused on the effects of fishing bans on economically important species, while impacts on freshwater macroinvertebrates in lake ecosystems have been rarely studied. This study used a before-and-after methodology to determine the short-term effects of the "ten-year fishing ban" on the macroinvertebrates of the Dianchi Lake, the largest highland freshwater lake in the upper Yangtze basin, between 2015 and 2022. Following the fishing ban, the overall macroinvertebrate species richness (median [interquartile]) across sites increased from 4 [2-6] to 5 [4-7]. The total density increased from 128 [80-272] to 212 [140-325] n/m². The median biomass increased from 0.18 [0.08-0.41] to 0.51 [0.26-2.36] g/m². In particular, the Chironomidae density in the offshore sites increased from 16.00 [0.00-32.00] to 33.30 [16.00-48.00] n/m², and the biomass increased from 0.03 [0.00-0.09] to 0.16 [0.07-0.22] g/m². Within the inshore sites, the aquatic insect density increased from 4 [1.33-15.33] to 56 [22.00-86.67] n/m². The Malacostraca density increased from 34.67 [11.67-95.33] to 110 [53.33-223.33] n/m², and the biomass increased from 0.43 [0.11-1.00] to 1.48 [0.50-2.00] g/m². Two endangered Margarya species were rediscovered at multiple sites compared to the pre-fishing ban period. A significant change in macroinvertebrate community structure across the lake was observed, which can be largely attributed to the fishing ban. The immediate increase in species richness, density, and biomass of most macroinvertebrate species suggests a combination of effects from both reduced exploitation pressure and lessened disturbances on lake habitats. The findings indicate that the fishing ban is beneficial for the recovery of most macroinvertebrate species in freshwater lakes.

Keywords: Benthic invertebrates; Dianchi lake; Fishing closure; Freshwater conservation; Lake management; Margarya.

MeSH terms

Animals
Conservation of Natural Resources
Ecosystem*
Endangered Species
Environmental Monitoring / methods
Fisheries
Hunting
Invertebrates* / physiology
Lakes / chemistry