不同类型缓控释肥对水稻产量形成和稻田氮素流失的影响

Effects of different types of controlled release fertilizer on rice yield and nitrogen loss of surface runoff

本研究以武运粳30号为试验材料,设置不施氮肥(N0)、当地水稻栽培农民习惯施肥量(N1)、氮肥减量18.2%(N2)、氮肥减量+脲酶抑制剂(N3)、硫包衣尿素(N4)、树脂包膜尿素(N5)、脲醛尿素(N6)、草酰胺(N7)等8个处理(N3处理~N7处理施氮量同N2处理),研究不同类型缓控释肥料对水稻产量及稻田氮素地表径流流失的影响。结果表明:(1)与N1处理相比较,氮肥减量的N3、N6和N7处理能够确保水稻产量。(2)N6和N7处理水稻生物产量相对较低,较高的经济系数是其产量不减的重要原因。(3)试验年度稻田共产生地表径流6次,累计地表径流水量为3.68×10~3m^3/hm^2。(4)稻季农田地表径流总氮流失量平均为11.34 kg/hm^2,氮肥减量条件下,通过不同缓控释肥的使用大部分能够显著降低稻季农田地表径流总氮质量浓度和总氮流失量。(5)氮肥减量的N4和N5处理使农田地表径流总氮素流失率显著降低。使用不同缓控释肥使水稻氮素偏流失率大部分得到显著降低。说明,氮肥减量条件下,脲醛尿素(N6)和草酰胺(N7)替代普通尿素在保证水稻产量的同时,减少了农田地表径流氮素流失量,降低了水稻氮素偏流失率。

In order to reveal the effects of different types of controlled release fertilizers on rice yield and nitrogen loss of surface runoff in a wheat-rice double cropping system,a field experiment was carried out with Wuyunjing 30 as tested material.Eight treatments such as no nitrogen fertilizer（ N0）,local farmer accustom nitrogen fertilizer application（ N1）,nitrogen reduction 18.2%（ N2）,nitrogen reduction 18.2% and urease inhibitor（ N3）,sulfur coated urea（ N4）,resin coated urea（ N5）,urea formaldehyde（ N6）,oxalic amide（ N7） were conducted. The results showed that rice yield could be assured under the treatments of N3,N6,and N7 compared with that under the treatment of N1. The biomass yield of rice under the treatments of N6 and N7 was relatively low,and the higher economic coefficient was an important reason for normal output. There were six times of surface runoff in this rice season,and the accumulative surface runoff was 3.68×10^3m^3/hm^2. The average total nitrogen loss of surface runoff was 11.34 kg/hm^2. In the condition of nitrogen reduction,total nitrogen concentration and total nitrogen loss of surface runoff could be significantly decreased through the use of some controlled release fertilizers. In the condition of nitrogen reduction,the total nitrogen loss rate was effectively decreased under the treatments of N4 and N5. Most of the rice nitrogen drift loss rate significantly decreased by using controlled release fertilizers. In conclusion,in the condition of nitrogen reduction,replacing ordinary urea with urea formaldehyde（ N6） and oxalic amide（ N7） could ensure rice yield,reduce the loss of nitrogen in surface runoff,and decrease the rate of nitrogen drift loss in rice.