To explore the ecological impact processes of the construction and operation of offshore wind farms on nekton communities, we conducted trawling surveys in the waters of the Wailuo Offshore Wind Farm in Zhanjiang in October 2019 (Construction period) and September 2020 (Operation period), respectively. We systematically evaluated the effects of wind farm construction and operation on nekton using methods including the relative importance index, community diversity indexes, ABC curves, and multivariate statistical analyses, combined with pre-construction background data. The results show that 24 species of nekton were sampled during the construction period, belonging to 23 genera, 19 families, and 11 orders. There are 95 species during the operation period, belonging to 65 genera, 43 families, and 16 orders. The dominant species in construction period (2 species) were fewer than those during operation period (6 species). Arius thalassinus and Mugil cephalus were the common dominant species. The Shannon-wiener diversity (H'), Margalef richness (D), and Pielou evenness (J) indexes were 0.282−3.530, 0.679−3.320, and 0.141−0.975, with mean values of 2.130, 2.040, and 0.674 in construction period, respectively; 2.180−5.920, 2.203−6.460 and 0.483−1.230, with mean values of 3.470, 4.320 and 0.812 in operation period, respectively. ABC curve analysis shows that the nekton communities in this area were moderately disturbed with poor community stability during construction and operation periods. The results indicate that the impact of offshore wind farm construction and operation on nekton follows a temporal response trajectory of "significant disturbance during the construction period, initial adaptation after construction, and gradual recovery during the operation period", and this dynamic provides a scientific basis for the ecological management of integrated wind power-aquaculture model.

To evaluate the impact of submarine cable magnetic fields from offshore wind farms on marine organisms, we used Litopenaeus vannamei juveniles (Body mass ca. 3 g, 30 individuals per exposure group and control group) and adults (Body mass ca. 25 g, 30 individuals per group) as experimental subjects to conduct a 14-day magnetic field (0.2 mT) exposure experiment. First, we observed the post-exposure, morphological changes in the hepatopancreas of juveniles, then performed an exposure experiment on adults under the same conditions to assess antioxidant enzyme activity in the hepatopancreas, and to analyze differential metabolites in both hepatopancreas and muscle tissues using non-targeted metabolomics technology. Results show that magnetic field exposure led to albino damage of the hepatopancreas of juveniles. Compared with the control group, the 0.2 mT group showed a significant decrease in superoxide dismutase (SOD) activity in the hepatopancreas of adults, an increase in glutathione peroxidase (GSH-Px) activity and a decrease in malondialdehyde (MDA) concentration. KEGG enrichment analysis reveals that differentially expressed metabolites in the hepatopancreas were primarily enriched in purine metabolism, phenylalanine metabolism, and arachidonic acid (AA) metabolism pathways, whereas those in muscle tissue were significantly associated with ABC transporters, amino acid biosynthesis, and neuroactive ligand-receptor interactions. In the hepatopancreas of adults, D-xylonic acid, guanosine monophosphate (GMP), adenosine 5'-monophosphate (AMP), cytidine 5'-monophosphate (CMP), uridine monophosphate (UMP) and leukotriene C₄ were upregulated. In contrast, succinate and L-threonic acid were downregulated. In muscle cells, astaxanthin was upregulated, AA and its derivatives 2-arachidonoyl glycerol (2-AG) and N-arachidonoyl dopamine (NADA) were downregulated, and taurine, D-malic acid, and D-erythrose 4-phosphate were significantly downregulated. The results reveal the molecular responses of magnetic field exposure to energy metabolism, oxidative defense, and inflammatory response in L. vannamei, providing basic data for assessing the impact of magnetic fields of submarine cables in wind farms on marine life.