不同缓控释肥料减氮对洞庭湖区双季稻田氮流失与作物吸收的影响

Effects of Nitrogen-Reducing of Different Slow/controlled Release Fertilizer on Nitrogen Uptake by Rice and Runoff Loss from Double Rice Field in Dongting Lake Area

本文采用田间试验研究了不同缓控释肥料减氮处理对双季稻田氮流失及水稻吸收氮的影响。结果表明,与常规施氮处理(Urea,纯N用量早稻150kg/hm2,晚稻180kg/hm)2相比,减氮30%的膜包衣尿素处理和减氮30%硫包衣尿素处理NH4+-N的径流损失量分别降低了34.1%(P<0.05)、26.6%(P<0.05),比未减氮复混肥处理减少50.2%(P<0.01)、44.6%(P<0.01);减氮30%膜包衣尿素处理的水溶性非无机氮(包括颗粒吸附态及有机态氮)和总氮径流损失较尿素处理减少29.0%(P>0.05)和26.3%(P>0.05);减N30%的膜包衣尿素处理植株氮的吸收量最高,分别比未减氮复混肥和尿素处理提高了9.3%(P<0.05)和5.5%(P>0.05);不同缓控释肥减氮处理对双季稻的产量没有明显影响,其氮肥农学效率早稻提高12.4%～35.8%,晚稻27.4%～56.6%;氮肥偏生产力早稻提高18.4%～39.14%,晚稻25.7%～46.5%;双季稻氮肥利用率以减N30%的膜包衣尿素处理最高,与不减氮的常规尿素处理相比,早、晚稻最高可提高23.5%和21.1%。

The effects of nitrogen-reducing of different slow/controlled release fertilizers on nutrient uptake and nitrogen loss of the double cropping rice field were studied in Dongting Lake area based on field experiment. The results showed that the amount of ammonium nitrogen loss rate in the treatments of both 70% N of Membrane-Coated Urea （MCU） and Sulfur-Coated Urea （SCU） was decreased by 34.1%（P〈0.05） and 26.6% （P〈0.05） compared with conventional nitrogen application （urea, N 150 kg/hm^2 in early rice and 180 kg/hm^2 in late rice） respectively; and was decrease by 50.2% （P〈0.01） and 44.6%（P〈0.01 ） compared with equal-N compost fertilizer treatment （Com 1 ） respectively;The 70% N MCU could reduced non-water dissolved nitrogen （including particles adsorbed and organic nitrogen） and total nitrogen runoff loss by 29.0% （P〉 0.05） and 26.3% （P〉 0.05） respectively, compared with urea treatment. Nitrogen absorption in 70% N MCU treatment was highest, and was increased by 9.3%（P〈0.05） and 5.5%（P〉 0.05） compared with Coml and Urea respectively. The nitrogen reducing treatments had no significant yield-reducing effect, but could significantly increase the nitrogen agronomic efficiency by 12.4%-35.8% in early rice and 27.4%-56.6% in late rice and nitrogen partial productivity by 18.4%-39.14% in early rice and 25.7%-46.5% in late rice; Especially, 70% N MCU had the highest nitrogen use efficiency, which raised 23.5% and 21.1% compared with urea treatment in early rice and in late rice respectively.