增值尿素的氨挥发特征及其对土壤微生物量碳和脲酶活性的影响

通过向普通尿素中添加风化煤粉、腐植酸钾和脱盐液，利用熔融造粒工艺制备出普通尿素（U）、风化煤尿素（F U）、腐植酸尿素（H A U）、脱盐液尿素（T U）3个增值尿素试验产品，在25℃条件下，进行土壤培养试验，研究了增值尿素的氨挥发特征及其对土壤微生物量碳、脲酶活性的影响。结果表明，与普通尿素相比，各增值尿素氨挥发累积量降低29.52%～39.78%，延迟了氨挥发的峰值；各增值尿素处理，在培养的前7天内土壤的脲酶活性降低，延缓了尿素态氮在土壤的转化速率；延缓了土壤微生物量碳峰值出现时间；风化煤和腐植酸尿素处理在整个培养期内表现处理了较好的稳定性，减少氨挥发效果明显。

Effects of Value-added Urea on Ammonia Volatilization,Soil Microbial Biomass Carbon and Soil Urease Activity

By adding weathered coal, humic acid and potassium salt solution to common urea and using melt granu-lation process, urea （U）, weathered coal urea（FU）, humic acid urea （HAU） and desalination liquid urea （TU） were prepared. Soil incubation under 25℃was conducted to study the ammonia volatilization characteristic, soil microbial biomass carbon and soil urease activity of urea and three kinds of value-added urea. The results showed that compared with the common urea, the accumulation of ammonia volatilization of all value-added urea were decreased by 29.52%to 39.78%, the peak of ammonia volatilization were deferred, the activity of value-added urease in soil were decreased within the ifrst 7 days, the conversion rate of urea nitrogen in soil were reduced, the time of soil microbial biomass car-bon peak were delayed, weathered coal urea and humic acid urea showed better stability during the whole incubation period and had obvious effects on reducing ammonia volatilization .