不同缓控释氮肥对高羊茅草坪生长及氮素挥发的影响

Effects of different slow/controlled release nitrogen fertilizer on tall fescue turf growth and nitrogen volatilization

通过田间试验,研究了氮释放期为30和60d的树脂包膜尿素(PCU30、PCU60),硫包衣尿素(SCU),抑制剂型缓释尿素(UI)和普通尿素(U)对高羊茅草坪生长、氮素吸收及氮素挥发的影响。结果表明,在全年施氮量260kg/hm2的情况下,PCU30、PCU60和SCU一年分春秋2次施用可以满足高羊茅草坪正常生长需要,其草屑累积量和氮素吸收量显著高于普通尿素一年4次施用处理;氮素气态损失方面,UI处理的氨挥发损失氮量高达44.42kg/hm2,显著高于其他施氮处理,其N2O排放氮量为6.46kg/hm2,显著低于其他施氮处理;PCU30、PCU60、SCU处理的氨挥发量和N2O排放氮量分别为17.67,13.59,18.54kg/hm2和8.14,6.92,9.91kg/hm2,显著低于U处理。综合考虑各种因素,建议高羊茅草坪一年分春秋2次施用树脂包膜尿素PCU60较为适宜,可有效提高肥料利用率、降低氮素挥发损失,环境效益明显。

Field experiments were conducted to study the effects of two kinds of macromolecule polymer coated urea that the nitrogen release period were 30 and 60 days（PCU30,PCU60）,sulfur coated urea（SCU）,urea mixed with nitrification inhibitor（UI） and urea（U） on grass growth,nitrogen uptake,ammonia and N2O volatilization of fertilizer in tall fescue turf.Results showed that application of fertilizer such as PCU30,PCU60,SCU in spring and autumn at total rate of 260 kg/hm2 per year could meet nitrogen requirement of grass normal growth.Meanwhile,the clipping yields and nitrogen uptake of those treatments were all significantly higher than U treatment at same N rate in one year with four times application.In terms of gaseous nitrogen loss,ammonia volatilization from UI was 44.42 kg/hm2,which was significantly higher than other treatments.But N2O emission of this treatment was 6.46 kg/hm2,significantly lower than others.The ammonia volatilization of PCU30,PCU60 and SCU treatments were 17.67,13.59 and 18.54 kg/hm2 and the N2O emissions were 8.14,6.92 and 9.91 kg/hm2 respectively.But all of them were significantly lower than the U treatment.Considering integrated factors,PCU60 should be taken as a suitable fertilizer on tall turf grass with twice application in spring and autumn for a year,which could increase nitrogen use efficiency and reduce nitrogen volatilization,showing an outstanding ecological and environmental benefit.