有机无机肥配施对麦-稻轮作系统土壤微生物学特性的影响

采用盆栽试验研究了不同比例有机无机肥配施对连续4茬麦-稻轮作后土壤微生物学特性的影响。结果表明,与对照相比,单施化肥处理促进了土壤微生物生物量碳、氮和微生物熵的增加,提高了土壤蔗糖酶、蛋白酶、脲酶活性,降低了过氧化氢酶活性,提高了放线菌的数量,但对土壤细菌、真菌数量的影响不明显;有机无机肥配施处理的土壤微生物生物量碳、微生物生物量氮、微生物熵、土壤酶活性及3大类土壤微生物数量显著高于单施化肥及对照处理;土壤微生物生物量碳、微生物生物量氮、微生物熵和3大类微生物数量随着有机肥配施比例的提高而增加,以配施30%有机肥处理的最高;土壤酶活性综合指数以配施20%有机肥处理的最高。可见,化肥配施有机肥特别是配施中高量有机肥更有利于改善土壤微生物学特性,提高土壤生产能力。

Effects of Combined Application of Organic and Inorganic Fertilizers on Soil Microbiological Characteristics in a Wheat-rice Rotation System

A pot experiment was conducted to investigate the effects of continuous application of organic and inorganic fertilizers on soil microbiological characteristics in a wheat-rice rotation system. The results showed that soil microbial biomass carbon（ SMBC ）, soil microbial biomass nitrogen（ SMBN ）, soil microbial quotient（SMQ）, enzyme activities of invertase, protease and urease, and the amount of actinomycete increased in inorganic fertilizer treatments, however the catalase activity decreased. Compared with the treatments of inorganic fertilizer and CK, combined application of organic and inorganic fertilizers significantly increased SMBC, SMBN, SMQ, soil enzyme activities, the amounts of bacteria, fungi and actinomycete, which increased with increasing rates of organic manure, and the highest were appeared in treatment of 30% organic fertilizer. Treatment of 80% inorganic fertilizer with 20% organic manure gave the highest comprehensive index of soil enzyme activities （GMea）. Therefore, combined application of inorganic fertilizer wit organic manure, especially at middle or high rates of organic manure, was propitious to improve soil microbiological characteristics than inorganic fertilizer alone.