WANG Xiaolin, YAN Long, JI Guang, DONG Jing, XU Yanzhao, WANG Aiyong, LIU Xiuze, WANG Bin, KONG Yefu
Journal of Dalian Fisheries University. 2025, 40(2): 298-307.
To evaluate fish diversity in the Liaohe Estuary and adjacent sea at autumn and to explore the applicability of environmental DNA (eDNA) metabarcoding in monitoring fish diversity,both seawater samples for eDNA and fish samples by bottom trawl survey were taken at ten survey stations in the Liaohe Estuary and adjacent sea in October 2023.High throughput sequencing and biological analysis were conducted separately.In total,37 fish species were detected in the eDNA sample ASV annotation results,2 of which were identified only at the genus level,and 16 fish species were identified in the fish samples by bottom trawl survey.13 fish species were totally identified by these two methods.The number of fish species detected by the eDNA metabarcoding technology was 2.3 times more than that by the bottom trawl survey.The differences in alpha diversity indices among the different stations based on the eDNA detection data were not significant.Principal component analysis (PCA) showed that the first two principal components could explain 57.04% of differences in fish communities (PC1 43.04%,PC2 14.0%),and there was little difference in fish community composition among sampling stations.Pearson correlation analysis showed a high correlation between the relative abundance of eDNA and relative catch (biomass,number of individuals) of bottom trawl surveys,with r values of 0.921 and 0.888,respectively,and the correlation was highly significant (P< 0.01).Redundancy analysis(RDA) results showed that there was no significant correlation between various water environmental factors (temperature,salinity,pH,DO,water depth) and fish community structure (P> 0.05).In summary,the eDNA technology had higher species detection efficiency than bottom trawl survey method,and there was a significant correlation between the relative abundance of the eDNA and the relative catch,indicating that the eDNA technology can be effectively applied to monitor and evaluate fish diversity in the Liaohe Estuary and its adjacent waters.
