2015-2024年春季东海带鱼保护区游泳动物共存模式的年间动态演变OA

To elucidate the interannual dynamics of co-occurrence patterns in the spring nekton community of the Hairtail National Aquatic Germplasm Reserve in the East China Sea and to assess their responses to climatic variability,we analyzed data from spring bottom-trawl surveys conducted from 2015 to 2024.This analysis incorporated the Oceanic Niño Index(ONI)and the Pacific Decadal Oscillation(PDO).The overall community co-occurrence pattern was characterized using an FE null model based on the standardized effect sizes(SES)of C-score and V-ratio.Subsequently,significant species pairs,key influential species pairs,and key associated species were identified.The results indicated that the spring nekton community exhibited an overall non-random structure throughout the study period.However,the co-occurrence pattern displayed marked interannual variability,with random,aggregated,and segregated patterns alternating across years.Aggregation was more prominent in 2018 and 2022,while stronger segregation signals were observed in 2016 and 2021.At the species-pair level,significant species pairs were identified in only a few years,totaling 26 significant pairs across the entire period.The year 2021 had the highest count,with 16 significant pairs.Based on this,four key associated species contributing significantly in specific years were further identified:Coilia mystus,Collichthys lucidus,Odontamblyopus rubicundus,and Apogon lineatus.No stable significant species pairs were detected across all years,indicating substantial interannual turnover in the high-contribution species combinations.The analyses exploring climate relationships revealed generally weak correlations between ONI,PDO(including their lagged terms),and the overall community co-occurrence pattern.Notably,V-ratio-SES exhibited a significant negative correlation with the ONI lagged by one year(p=0.037).This suggests that higher ONI values in the preceding year were associated with weaker community aggregation or a shift towards a more segregated structure.These findings indicate that the spring nekton co-occurrence pattern in the reserve results from the combined effects of an overall non-random community structure,high-contribution species pairs in specific years,and limited climate signals,and may provide a scientific reference for community dynamics monitoring and adaptive management in the reserve.