Biochar, a valuable product from the pyrolysis of agricultural and forestry residues, has been widely applied as soil amendment. However, the effect of different types of biochar on the soil microorganisms and associated biochemical processes in paddy soil remains ambiguous. In this study, we investigated the impact of biochars derived from different feedstocks (rice straw, orange peel or bamboo powder) on the dynamics of short chain fatty acids (SCFAs), iron concentration and bacterial community in paddy soil within 90 days of anaerobic incubation. Results showed that biochar amendment overall inhibited the accumulation of SCFAs while accelerated the Fe(III) reduction process in paddy soil. Besides, 16S rRNA gene sequencing results demonstrated that the alpha diversity of bacterial community significantly decreased by biochar amendments at Day 1 but was relatively unaffected in the end of incubation, and incubation time was the major driver for the succession of bacterial community. Furthermore, significant correlations between parameters (e.g. SCFAs and iron concentration) and bacterial taxa (e.g. Clostridia, Syntrophus, Syntrophobacter and Desulfatiglans) were observed. Overall, our findings demonstrated that the amendment of different types of biochar altered SCFAs profile, Fe(III) reduction and bacterial biodiversity in rice paddy soil.

中文翻译：

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稻田土壤中短链脂肪酸谱的变化，Fe（III）的减少和生物炭修正下细菌群落的变化。

生物炭是农业和林业残留物热解的一种有价值的产品，已被广泛用作土壤改良剂。然而，不同类型的生物炭对稻田土壤微生物及相关生化过程的影响仍然不明确。在这项研究中，我们调查了厌氧培养后90天内，不同原料（稻草，橘皮或竹粉）生物炭对稻田土壤中短链脂肪酸（SCFA），铁浓度和细菌群落动态的影响。 。结果表明，生物炭改良剂总体上抑制了稻田土壤中SCFA的积累，同时促进了Fe（III）还原过程。除了，16S rRNA基因测序结果表明，细菌群落的α多样性在第1天被生物炭修饰显着降低，但在孵育结束时相对不受影响，并且孵育时间是细菌群落继承的主要驱动力。此外，还观察到参数（例如，SCFA和铁浓度）与细菌类群（例如，梭状芽胞杆菌，嗜中性丝囊病，滑膜细菌和脱硫蛋白）之间存在显着相关性。总体而言，我们的研究结果表明，不同类型生物炭的改良改变了稻田土壤中的SCFAs分布，Fe（III）还原和细菌生物多样性。观察到了SCFA和铁的浓度）和细菌类群（例如梭状芽胞杆菌，嗜中风梭菌，滋养细菌和脱硫杆菌）。总体而言，我们的研究结果表明，不同类型生物炭的改良改变了稻田土壤中的SCFAs分布，Fe（III）还原和细菌生物多样性。观察到了SCFA和铁的浓度）和细菌类群（例如梭状芽胞杆菌，嗜中风梭菌，滋养细菌和脱硫杆菌）。总体而言，我们的研究结果表明，不同类型生物炭的改良改变了稻田土壤中的SCFAs分布，Fe（III）还原和细菌生物多样性。