箱塘联动养殖池塘水环境和微生物群落结构特征OA

To systematically investigate the water environmental characteristics and microbial community structure in a net-cage pond integrated aquaculture system,this study selected one integrated aquaculture pond and one conventional monoculture pond as parallel research subjects.During the entire culture cycle,we conducted on-site real-time monitoring,laboratory physicochemical parameter analysis,and nitrogen and phosphorus budget estimation,combined with 16S rRNA gene high-throughput sequencing,to comprehensively characterize the spatiotemporal distribution patterns of environmental factors and microbial community composition.The results showed that the average proportions of nitrate nitrogen(NO3--N)to total nitrogen(TN)and soluble reactive phosphorus(PO43--P)to total phosphorus(TP)in the water column of the integrated pond reached(72.65±9.50)%and(87.95±11.81)%,respectively.The annual average values of permanganate index(CODMn)and chlorophyll a(Chl.a)were(6.56±1.86)mg/L and(2.85±0.77)μg/L,respectively,which were significantly lower than the corresponding values in the conventional pond.Sediment nitrate reductase(S-NR)and alkaline phosphatase(S-ALP)activities exhibited significant correlations with multiple nitrogen and phosphorus indicators in the overlying water.The total nitrogen and phosphorus inputs of the integrated system were 488.35 kg and 112.11 kg,respectively,with feed input and sediment deposition identified as the dominant pathways for nitrogen and phosphorus loading and output.High-throughput sequencing results revealed that Proteobacteria,Actinobacteriota,and Bacteroidota were the dominant bacterial phyla in the integrated pond.At the genus level,genera including Limnohabitans,Aurantimicrobium,Flavobacterium,and Rhodobacter were significantly enriched.Mantel test results indicated that TN and NO3--N were the key environmental factors driving the variation of bacterial community structure.PICRUSt2 functional prediction demonstrated that metabolic pathways related to amino acid metabolism,pyruvate metabolism,fatty acid degradation,bacterial chemotaxis,and bacterial secretion system were significantly enriched in the integrated pond,suggesting that the microbial community in this system possessed stronger functional potentials for organic nitrogen mineralization,diverse carbon source utilization,and environmental stress adaptation.