Abstract Yellow River Delta undergoes intensive conversion from natural wetland to agricultural fields and artificial woodland. In this study, we analysed how the conversion affects bacterial community diversity and composition by Illumina Miseq sequencing combined with functional prediction. Compared to natural wetland, arable land and woodland were featured with higher soil organic matter, total nitrogen and bacterial diversity, but lower electrical conductivity. The bacteria Gemmatimonadetes related to soil organic matter and total nitrogen, was enriched in arable land, while salt-resistant bacteria (e.g. phylum Chloroflexi and its class Ardenticatenia) were abundant in natural wetland. Moreover, the relative abundances of the nitrifying bacteria Nitrospira and Nitrosospira were significantly higher in arable land and woodland than in natural wetland, suggesting that land use changes significantly affect the bacterial processes involved in nitrogen cycling. Redundancy analysis (RDA) showed that the differences in bacterial community were attributed to soil nutrient-related properties (i.e., total nitrogen and soil organic matter), soil salinity (i.e., electrical conductivity), and heavy metals (i.e. Cu and Cr). PICRUSt results revealed that land use conversion from natural wetland to arable land increased soil functions, e.g., biosynthesis process and oxidative phosphorylation. The data help us elucidate how land use changes affect terrestrial ecosystem function, and advise local farmers to apply the suitable land-use strategies and keep agricultural sustainable development.

中文翻译：

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黄河三角洲长期土地利用转换的土壤细菌群落响应

摘要 黄河三角洲正经历着从天然湿地向农田和人工林地的密集转变。在本研究中，我们通过 Illumina Miseq 测序结合功能预测分析了转化如何影响细菌群落多样性和组成。与天然湿地相比，耕地和林地具有较高的土壤有机质、全氮和细菌多样性，但电导率较低。与土壤有机质和总氮相关的细菌Gemmatimonadetes在耕地中富集，而耐盐细菌（如Chloroflexi及其类Ardenticatenia）在天然湿地中丰富。而且，耕地和林地中硝化细菌 Nitrospira 和 Nitrosospira 的相对丰度显着高于天然湿地，表明土地利用变化显着影响了参与氮循环的细菌过程。冗余分析（RDA）表明，细菌群落的差异归因于土壤养分相关特性（即总氮和土壤有机质）、土壤盐度（即电导率）和重金属（即 Cu 和 Cr）。PICRUSt 结果表明，从天然湿地到耕地的土地利用转化增加了土壤功能，例如生物合成过程和氧化磷酸化。这些数据帮助我们阐明土地利用变化如何影响陆地生态系统功能，