控释肥对东北春玉米产量和土壤氨挥发的影响

针对控释肥施用条件下作物产量与土壤氨挥发特征不明晰的问题,以东北春玉米种植模式为研究对象,采用德尔格氨管法(DTM法)研究了不同施肥处理农民常规施肥处理(施氮量为180 kg N·hm~(-2),FP)、控释肥施氮量180 kg N·hm~(-2)处理(CRF180)和控释肥施氮量144 kg N·hm~(-2)处理(CRF144)]下土壤氨挥发动态变化特征、土壤氨挥发总量及玉米产量。结果表明:受施肥和降雨因素的影响,每个处理氨挥发峰值均出现在施肥后(基肥和追肥)第1~2 d、第11~12 d左右;FP处理在12~14 d后氨挥发速率降低至零,但CRF180、CRF144处理仍有少量挥发。全生育期FP、CRF180、CRF144处理来自氮肥的氨挥发量依次为19.9、23.8、19.6 kg·hm~(-2),差异不显著(P0.05),损失率分别为11.06%、13.22%、13.61%。CRF144处理和FP处理产量都保持在12 t·hm~(-2)以上,其两者不存在显著差异,但CRF144处理能够显著地提高氮肥农学效率和偏生产力(P0.05)。综合考虑氨挥发量与产量,在现有施氮量基础上减少20%,并且施用控释肥是该地区春玉米农田减肥增效适宜的推广技术。

Effect of controlled-release fertilizer on the yield and soil ammonia volatilization of spring maize in northeast China

The impacts of applying nitrogen controlled-release fertilizer (CRF) on crop yield and ammonia volatilization from spring maize systems are unclear. To provide clarity to this issue, we investigated the impacts of different fertilization treatments, i.e., conventional farmer''s practices (FP) (180 kg N·hm^-2), CRF180 (180 kg N·hm^-2), and CRF144 (144 kg N·hm^-2), on maize yield of and ammonia volatilization from spring maize systems in northeast China by using the Drager-Tube Method (DTM). The results showed that the characteristics of ammonia volatilization were primarily controlled via fertilization and rainfall and were similar across different treatments. Peaks of ammonia volatilization were observed on days 1~2 and 11~12 following base and top fertilization, respectively. The peaks gradually decreased to zero 12~14 days following the fertilization events under FP. However, there was a small amount of ammonia volatilization under CRF180 and CRF144 14 days after the fertilization events. The annual total ammonia emissions were 19.9, 23.8, and 19.6 kg·hm^-2, respectively, under FP, CRF180, and CRF144 and were not significantly (P>0.05) different across the treatments. The ammonia loss rates accounted for 11.06%, 13.22%, and 13.61% of the nitrogen applied, respectively, for FP, CRF180, and CRF144. The maize yields were higher than 12 t·hm^-2 for both FP and CRF144. There was no significant difference in agronomic efficiency between CRF180 and FP and in maize yield between CRF144 and FP. However, the CRF144 treatment significantly improved agricultural efficiency and the partial productivity of nitrogen fertilizer (P<0.05) and had a positive effect on reducing the labor cost. Therefore, the practice of reducing the nitrogen application by 20% in combination with applying CRF is a suitable technology for increasing crop yield of and reducing ammonia volatilization from spring maize fields in this area.