短期内有机肥增施对高原土壤养分和细菌群落的影响

Effects of short-term application of organic fertilizer on soil nutrients and bacterial community in plateau

【目的】探索短期增施有机肥对高原土壤养分和细菌群落结构的影响。【方法】采用高通量测序技术对3种施肥处理(施加100%常规复合化肥、50%常规化肥+30000 kg/hm^(2)有机肥、25%常规化肥+55000 kg/hm^(2)有机肥)作用下的土壤进行养分含量和细菌群落结构分析。【结果】增施有机肥降低了土壤pH,提高了有机质、全氮、有效磷、有效钾、有效铜、有效铁的含量。在已知细菌群落中,3种不同处理下土壤的优势菌门包括变形菌门、酸杆菌门、拟杆菌门、放线菌门、芽单胞菌门,其中酸杆菌门和变形菌门在增施有机肥处理下,相对丰度分别提高了3.99%和13.97%。鞘氨醇单胞菌属和芽单胞菌属是已知细菌群落中的优势属,在3种处理下的相对丰度存在差异。短期增施有机肥提高了土壤细菌丰富度,降低了细菌多样性。Pearson分析结果表明有机质和pH是影响细菌丰富度和多样性的主要驱动因子。KEGG功能预测表明基于合适量的有机肥增施下,土壤细菌与代谢、运输以及传导等功能相关的基因上调。【结论】短期内增施有机肥在一定程度上提高了土壤的养分含量和质量,同时也改变了土壤细菌群落和功能。

【Objective】The present study aimed to explore the effects of short-term application of organic fertilizer on soil nutrients and bacterial community structure in the plateau.【Method】High-throughput sequencing technique was used to analyze the soil nutrient content and bacterial community structure under three fertilization treatments(100% conventional compound fertilizer, 50% conventional chemical fertilizer plus 30 000 kg/hm^(2) organic fertilizer, 25% conventional chemical fertilizer plus 55 000 kg/hm^(2) organic fertilizer). 【Result】It was found that the application of organic fertilizer decreased the pH of soil, increased the contents of organic matter, total nitrogen, available phosphorus, available potassium, available copper and available iron. Among the known soil bacterial communities, the dominant phyla under three different treatments included Proteobacteria, Acidobacteria, Bacteroidetes, Actinobacteria and Gemmatimonadetes, in which the relative abundance of Acidobacteria and Proteobacteria increased by 3.99% and 13.97% under the treatment of organic fertilizer, respectively. Sphingomonas and Gemmatimonas were the known dominant genera, and their relative abundances were different among the three treatments. Short-term application of organic fertilizer improved soil bacterial richness and reduced diversity. Pearson’s results showed that organic matter and pH were the main drivers of bacterial richness and diversity. KEGG functional prediction indicated that soil bacteria were genetically modified to functions such as metabolism, transportation, and conduction based on the appropriate application rate of organic fertilizer.【Conclusion】In the short term, increasing the application of organic fertilizer not only improved the nutrient content and quality of soil to a certain extent, but also changed the soil bacterial community and function.