缓释氮肥减少菜田土壤硝酸盐淋溶研究

Research on Controlled Release Nitrogen Fertilizer Reducing Nitrate Leaching in Vegetable Fields

为了提高化学氮肥利用效率、减少氮素淋溶造成的环境污染风险。采用大田试验的方法,研究在菜田土壤条件下,施用树脂包衣尿素、硫包衣尿素、添加DCD氮肥3种措施对土壤硝态氮累积和圆白菜硝酸盐含量的影响。研究表明:树脂包衣尿素能明显提高圆白菜的经济产量,较常规增产15.0%,硫包衣增产7.3%,添加DCD氮肥与常规持平;施用添加DCD氮肥圆白菜硝酸盐含量比常规N降低20.3%,而树脂包衣与硫包衣分别增加了11.3%、20.3%;3种缓释氮素在一定时期能够将土壤硝酸盐保持在圆白菜的主要根系层,树脂包衣在圆白菜莲座期、结球期和收获期效果比较稳定,硫包衣和添加DCD氮肥前期效果好,后期淋溶加强。

To improve the chemical nitrogen fertilizer use efficiency,reduce environmental pollution risk caused by nitrogen leaching,research and application of controlled release fertilizer are given special attention in recent years. This paper researches on the effects of application of three kinds of controlled release fertilizers which are resin coated urea,sulfur coated urea and DCD added nitrogen on nitrate accumulation in cabbage and soil nitrate leaching by the method of field experiment,under highly fertility soil conditions. The results showed： resin coated urea could improved the cabbage＇s economic output and biomass significantly by 15. 0% comparing the normal,sulfur coated urea improved by 7. 3% ,the effect of DCD added nitrogen was not significant comparing the normal; nitrate content in cabbage applied DCD added nitrogen was lower than the conventional N by 20. 3% ,but resin coated urea and sulfur coated urea improved by 11. 3% ,20. 3% respectively; The three kinds of controlled release fertilizer could be keep nitrate in the main root in the cabbage in a certain period,the effects of resin coating was relatively stable at rosette stage, heading stage and harvesting time,sulfur coated and DCD added nitrogen were effective in the early period,leaching was strengthened in the latter period.