轮作水稻对大棚土壤硝化作用和氮挥发的影响

发布时间：2018-12-16 09:12

【摘要】：通过大棚茄子—水稻轮作(GER)和大棚茄子—揭膜休闲(GEF)2种栽培模式在大棚茄子栽培期间土壤硝化作用强度、氨挥发速率和土壤水热条件指标动态变化的比较,研究了轮作水稻对大棚土壤硝化作用和氨挥发的影响。结果表明:(1)GER模式在大棚茄子各生育期土壤硝化作用强度都显著高于GEF土壤,苗期最高峰时表土和根际土硝化作用强度分别为56.6,101.4mg/(kg·h),比GEF模式增加了34.8%和42.4%;(2)GER模式在大棚茄子基肥和追肥施用后土壤氨挥发速率都显著低于GEF土壤,累积氨挥发量为1.21kg/hm~2,比GEF模式减少了76.7%;(3)GER模式在大棚茄子各生育期表土和根际土NH4+—N含量都低于GEF土壤,NO3-—N含量高于GEF模式;(4)GER和GEF模式在大棚茄子收获后表土NH4+—N含量分别为30.4,45.9mg/kg,NO3-—N含量分别为265.4,255.5mg/kg,存在明显的氮素累积。夏季轮作水稻缓解了大棚土壤酸化、提高了大棚茄子生长期间土壤pH、温度和含水量,对大棚土壤硝化作用有明显的促进作用,可减少土壤氨挥发损失。但硝化作用强度的增加促进了土壤中硝酸根的累积,存在加剧土壤次生盐渍化和氮损失的风险,应加强轮作周期氮肥合理施用技术研究。
[Abstract]:The dynamic changes of soil nitrification intensity, ammonia volatilization rate and soil water and heat condition index were compared between eggplant and rice rotation (GER) in greenhouse and eggplant in greenhouse during cultivation period of soil nitrification, ammonia volatilization rate and soil water and heat condition. The effects of rotation rice on nitrification and ammonia volatilization in greenhouse soil were studied. The results showed that: (1) the nitrification intensity of GER model was significantly higher than that of GEF soil at all growth stages of eggplant in greenhouse, and the nitrification intensity of topsoil and rhizosphere soil at the highest peak of seedling stage was 56.6101.4mg/ (kg h), respectively. Compared with GEF model, it increased by 34.8% and 42.4%. (2) the ammonia volatilization rate of GER model was significantly lower than that of GEF soil after applying basal fertilizer and topdressing fertilizer in greenhouse, and the accumulated ammonia volatilization was 1.21 kg / hm ~ (-2), which was 76. 7% lower than that of GEF model; (3) the content of NH4-N in topsoil and rhizosphere soil of eggplant in greenhouse was lower than that in GEF soil, and the content of NO3--N was higher than that of GEF model. (4) the content of NH4 -N in the topsoil of GER and GEF was 30.4 mg / kg 路kg ~ (-3) mg 路kg ~ (-3) N, respectively, which was 265.4255.5 mg / kg ~ (-1) 路kg ~ (-1), respectively. Rotation of rice in summer alleviated soil acidification, increased soil pH, temperature and water content during greenhouse eggplant growth, significantly promoted soil nitrification and reduced ammonia volatilization loss in greenhouse. However, the increase of nitrification intensity promoted the accumulation of nitrate in soil, which resulted in the risk of soil secondary salinization and nitrogen loss. Therefore, the study on rational application of nitrogen fertilizer during rotation period should be strengthened.
【作者单位】：浙江大学土水资源与环境研究所;浙江省农业科学院环境资源与土壤肥料研究所;
【基金】：国家自然科学基金项目(31000941) 公益性行业(农业)科研专项(201303103) 国际植物营养研究所资助项目(Zhejiang-25)
【分类号】：S153

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