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Soil microorganisms play a vital role in biogeochemical processes and nutrient turnover in agricultural ecosystems. However, the information on how the structure and co-occurrence patterns of microbial communities respond to the change of planting methods is still limited. In this study, a total of 34 soil samples were collected from 17 different elds of two planting types (wheat and orchards) along the Taige Canal in Yangtze River Delta. The distribution and diversity of bacterial and fungal communities in soil were determined using amplicon sequencing targeting the 16S rRNA gene and ITS gene, respectively. The dominated bacteria were Proteobacteria, Acidobacteriota, Actinobacteriota, Chloro exi, Bacteroidota, and Firmicutes. The relative abundance of Actinobacteriota and Firmicutes was higher in the orchards, while Chloro exi and Nitrospirota were more abundant in wheat elds. Ascomycota, Mortierellomycota, and Basidiomycota were the predominant fungi in both types of soils. The diversity of bacterial and fungal communities was greater in the wheat elds than in the orchards. The statistical analyses showed that pH was the main factor shaping the community structure. Moreover, high co-occurrence patterns of bacteria and fungi were con rmed in both wheat elds and orchards. Network analyses showed that both the wheat elds and orchards occurred modular structure, which mainly contained nodes of Acidobacteriota, Chloro exi, Gemmatimonadota, Nitrospirota and Ascomycota. In summary, our work showed the co-occurrence network and the convergence/divergence of microbial community structure in wheat elds and orchards, giving a comprehensive understanding of the microbe-microbe interaction during planting methods changes. HighlightsThe diversity of both bacteria and fungi were higher in the wheat elds than in orchards. pH was the main factor affected the soil bacterial in wheat elds, while WC, TOC and TN all had great in uences on bacterial community in the orchards.Co-occurrence of bacteria and fungi were both investigated in wheat and orchard soils.

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The working principle of the Pelamis wave energy converter is described in this paper. The sectional size suitable for the outside sea of Xiamen Bay is redesigned according to the Froude and Strouhal similarity criteria. The swing angles, hydrodynamic coefficients, and wave exciting forces are calculated based on the AQWA hydrodynamic software and the average outside sea condition of Xiamen Bay. It is concluded that the Pelamis after redesigned by the Froude and Strouhal similarity criteria can run better in the outside sea area of Xiamen Bay. The three sections indirectly contacted with the fixed axis have larger swing angles. The wave period and height affect the speed of the response of the section and its swing angle range, respectively. The larger the total forces, the larger the swing angles. The wave circular frequency has a greater effect on the added mass and the wave exciting force than on the radiation damping; the heave added mass and the heave wave exciting force will become smaller when the heave radiation damping becomes larger with the increase of the wave circular frequency.