湖北省油菜种植氮足迹分析

Aanalysis of Nitrogen Footprint for Rape Cultivation in Hubei Province

农业领域大量活性氮损失造成的环境污染问题日渐突出,分析农业生产过程中活性氮的排放特征及其影响因素,对指导农业生产的低氮化具有一定现实意义。该文以湖北省油菜种植大县沙洋县为案例地,基于生命周期分析法,核算油菜种植过程的氮足迹,并分析不同耕作方式、轮作模式和肥料类型对油菜田间种植阶段活性氮排放的影响。结果表明,油菜田间种植环节产生的活性氮占总排放量的98.13%,是整个生命周期过程中活性氮排放的主要来源。免耕较常规翻耕可减少1.31%的活性氮排放。轮作方式对活性氮排放影响显著,前茬为旱作棉花情况下的活性氮是前茬作物为水稻的1.4倍。肥料类型对所排放活性氮的组分有显著影响,施用有机肥可有效减少活性氮排放。研究结果可为农业低氮种植、发展低碳农业提供参考。

The environmental pollution caused by the loss of reactive nitrogen in agriculture has become increasingly serious.Analyzing the emission characteristics and the impact factors of reactive nitrogen in agricultural production process had practical significance to guide the low-nitrogen agricultural production activities. Based on the life cycle analysis（LCA）, the nitrogen footprint was calculated and the effects of different farming patterns, rotation systems and fertilizer types on the reactive nitrogen emission for rape cultivation were analyzed in Shayang Country, Hubei Province. The results showed that the stage of rape planting was the main source of reactive nitrogen emission in the entire life cycle of rape cultivation, which accounted for98.13% of total emission. Compared with conventional tillage, no-tillage reduced approximately 1.31% of reactive nitrogen emission. Rotation system ssignificantly affected the release of reactive nitrogen. When the former crop was cotton, the reactive nitrogen emission was 1.4 times that of paddy as the former crop. Fertilizer types could significantly affect the components of reactive nitrogen, and the application of organic manure could effectively reduce the release of reactive nitrogen. The results can provide a reference for low-nitrogen plantation and the development of low-carbon agriculture.