氮素和生物调控下稻草还田对土壤肥力和产量的影响

采用稻草整株全量还田方式,设置了高氮和低氮2个水平,配合有无生物腐解剂处理,以当地农民习惯施肥为对照,对稻草还田前后的理化性质做了系统的分析,进而确定最佳的还田方式。结果表明,稻草还田提高了土壤的碱解氮、速效磷、速效钾和有效硅含量,降低了土壤容重,其中稻草还田2年高氮加生物腐解剂处理的各项指标最佳,碱解氮、速效磷、速效钾和有效硅含量分别比未还田前提高了14.3%、9.7%、8.5%、23.9%,土壤容重较农民习惯施肥处理降低了9.34%,水稻产量提高了10.6%。

Effect of straw returning to field on the soil fertility and yield under the biological and nitrogen manipulation

The rice straw was returned to the field as using the whole plantlet, to set up the high level nitrogen and low level nitrogen, biological decomposition agents and no biological decomposition agents were set up in certain treatments, respectively, took the fertilization habit of local peasants as the control, soil physical and chemical properties were analysed systematically, and then determined the best way to returning soil. The results showed that the contents of the soil alkali-hydrolyzable nitrogen, available phosphorus, available potassium and effective silicon were increased and the soil bulk density was reduced. The contents of the alkali-hydrolyzable nitrogen, available phosphorus, available potassium and effective silicon in the treatment which the rice straw returned to field for two years adding with high-level nitrogen and biological agent was the optimum and improved 14.3%, 9.7%, 8.5%, 23.9% than previous contents of these indicators in the soils, respectively. The soil bulk density was reduced 9.34% than that of fertilization habit of local peasants. The yield of rice in the field was increased to 10.6% under the rice straw returning.