控释尿素对土壤氨挥发及脲酶活性和氮淋溶的影响

Effects of Controlled-release Urea on Soil Ammonia Volatilization,Urease Activity and N Leaching

为了解控释尿素氨挥发特征、氮淋溶特性及其对土壤脲酶活性的影响,为控释肥新产品的研发提供技术和理论支撑,采用静态吸收法和土壤淋溶法室内模拟试验,研究了2种控释尿素在红壤和褐土中的氨挥发、脲酶活性和氮淋溶情况。结果表明：控释肥不同程度降低了氨挥发和氮淋溶量。与普通尿素相比,控释尿素1和控释尿素2在红壤中氨挥发累积量减少60.0%-62.6%,褐土中减少42.9%-46.3%,两者显著降低了氨挥发的峰值,且在整个培养期表现出较好的稳定性。在施肥后的30d内,控释尿素降低了土壤脲酶活性,延缓了尿素态氮在土壤中的转化进程,氮淋溶量分别较普通尿素少,氮淋洗量分别降低14.8%-25.9%和19.7-34.5%。控释尿素较普通尿素在消减氨排放和氮淋溶上具有明显的效果。

The ammonia volatilization, urease activity and nitrogen leaching of two controlled-release urea in red soil and brown soil were analyzed by static absorption and soil leaching methods to study the effect of controlled-release urea on ammonia volatilization, nitrogen leaching and soil urease activity and to provide the technical and theoretical support for development of new controlled-release fertilizers. The results showed that controlled-release fertilizer reduces ammonia volatilization and nitrogen leaching loss to varying degree. Ammonia volatilization accumulation of controlled-release urea 1 and 2 reduces by 60.0%-62.6% and 42.9% -46.3% in red soil and brown soil compared with common urea respectively. Controlled-release urea reduces the peak value of ammonia volatilization significantly, performances the better stability during whole culture period, reduce soil urease activity and delay the transformation process of urea-N in soil within 30 d after application. Nitrogen leaching loss of controlled-release urea 1 and 2 is 14.8%-25. 9% and 19.7-34. 5% lower than common urea. In conclusion, controlled-release urea has the significant reduction effect on ammonia emission and nitrogen leaching loss compared with common urea.