Effects of Various Interference Intensities on the Soil Bacterial Communities Diversity in the Sanjiang Plain, Northeast China

Large-scale agricultural land reclamation activities can trigger substantial changes in the soil bacterial community by disturbances associated with growth of crops and addition of fertilizers and pesticides. In this study, the bacterial 16S gene was sequenced on the Illumina MiSeq platform for bacterial identification and taxonomy. We investigated the (i) soil bacterial diversity and community composition in natural marsh, moderate and severe intensity of interference in wetlands, and (ii) the relationship between soil physical and chemical properties, and soil bacterial community structures in order to understand the effects of interference intensities on the marsh soil environment in the Sanjiang Plain wetland, Northeast China. The natural marsh soil contained most of 573 operational taxonomic units (OTUs) between all the three sites (n=1241), while wetland soils of moderate and severe intensity of interference had only 510 and 401 OTUs, respectively. The soil bacterial diversity and richness indices of all disturbed wetlands presented a decline at the OTU level, alpha diversity (Shannon diversity and Chao and Ace diversities). In addition, the composition of soil bacterial communities showed different trends and structure after the disturbance. There were significant variation in unclassified genera and some dominant genera (relative abundance>1% in at least one site) between natural marsh and difference in interference intensities in disturbed wetlands, including Acidobacteria, Proteobacteria, Verrucomicrobia, Actinobacteria, Chlorobi and Gemmatimonadetes. Composition of soil bacterial community was affected by Soil Moisture, pH, Soil Organic Carbon, Total Nitrogen, Available Nitrogen, Total Phosphorus, Available Phosphorus, Total Potassium, Nitrate Nitrogen, Available Potassium and Ammonium Nitrogen. This study will provide a fundamental scope to understand the bacterial community structure in wetland ecosystems and the environmental function as a predictor of bacterial community composition. (C) 2018 Friends Science Publishers