利用江西省农业科学院31年的长期肥料定位试验，选取不施肥(对照)、单施化肥、70%化肥配施30%有机肥、50%化肥配施50%有机肥和30%化肥配施70%有机肥等5个处理，通过常规分析和454-高通量测序技术，研究了长期不同施肥条件下，我国南方典型水稻土养分含量和真菌群落结构的变化。结果表明，在酸性水稻土上，长期单施化肥显著降低土壤pH值，但随着有机肥配施比例的提高pH明显上升；有机和无机肥配施显著提高土壤有机质、有效氮磷含量以及微生物碳氮量。单施化肥土壤真菌18S rDNA序列数比配施有机肥的多1倍，但真菌种(属)数减少了11~40种；前20种优势真菌的丰富度占真菌总量的78.82%~91.51%，以子囊菌最多(7~13种)，所占比例最大(23.13%~75.09%)；与对照相比，配施有机肥的土壤中有14~15种优势真菌与之相同，而单施化肥的土壤中仅有10种一致；主成分分析结果表明单施化肥处理的真菌群落组成与其他各处理存在显著差异。因此，单施化肥造成土壤酸化加剧，真菌数量成倍增加，但种类显著减少，其丰富度和多样性明显降低，并改变优势真菌种群，相应提高了土壤病原真菌过度繁殖的风险。而有机和无机肥配施有利于维持水稻土壤健康生态环境和真菌种群多样性。%A long-term field experiment was carried out for 31 years in Jiangxi Academy of Agricultural Sciences with a typical paddy soil in South China to study the influence of fertilizer application on changes of soil nutrients and fungal communities by rational analysis and 454 high-throughput sequencing technology. The fertilization treatments included control (without fertilizer), sole chemical fertilizer, 70% chemical fertilizer in combination with 30% organic fertilizer, 50% chemical fertilizer in combina-tion with 50% organic fertilizer and 30% chemical fertilizer in combination with 70% organic fertilizer. The soil pH decreased in the treatment of sole chemical fertilizer, but increased obviously with the proportion of organic fertilizer increased. Or-ganic-inorganic fertilizations significantly increased organic matter, available nitrogen and phosphorus, and microbial biomass carbon and nitrogen in the soil. The number of soil fungal 18S rDNA sequences was doubled while the species number of fungi decreased by 11-40 when received chemical fertilizer only, compared with the treatment of organic-inorganic fertilization. The top 20 predominant fungi ranged from 78.82% to 91.51% of the total in soil, and among them 7-13 species attributed to Ascomy-cetes which was the largest soil fungal group and accounted for 23.13%-75.09% of the top 20 predominant fungi. Compared with the control, 14-15 of the same species of dominant fungi were found in the treatment of organic-inorganic fertilizers but only nine in the treatment of sole chemical fertilizer. Principal component analysis showed the significant difference in soil fungal commu- nity compositions between treatment of sole chemical fertilizer and others. In general, sole application of chemical fertilizer re-sults in soil acidification, and exponential increment of soil fungi, but significant reduction in their species, richness and diversity indexes, suggesting the great changes in fungal community composition and the risk of over production of pathogen fungi in the soil. On the contrary, organic-inorganic fertilization treatment is beneficial to maintain the healthy ecological environment of paddy soil and the diversity of soil fungal communities.
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