包膜尿素在盐碱土壤中氮素转化及其对玉米增产效应的研究

为探究包膜尿素一次性基施提高玉米氮素利用效率及增产机制。采用田间小区试验,比较施用不同材料包膜尿素和施用普通尿素对土壤氮素转化特征及玉米增产效应的差异。结果表明,与施用普通尿素相比,包膜尿素在玉米生长发育前期可抑制土壤中的脲酶活性,处理3、处理4、处理5对土壤脲酶抑制率分别达到27.06%、28.36%和39.50%;施用包膜尿素还可以延缓氮肥在土壤中的释放进程,保证在玉米生长后期,有充足的氮素释放。在玉米抽穗期,处理3、处理4、处理5的土壤碱解氮含量分别比对照(施用普通尿素)高出40.33%、66.64%和53.89%,同时施用缓释包膜尿素还可显著提高玉米籽粒产量。处理4(2#包膜尿素)效果最佳,比普通尿素处理增产26.87%,氮素偏生产力、氮农学效率和氮素利用率分别比对照增加13.13 kg grain/kgN、6.76 kg grain/kgN和10.33%。

Transformation of Coated Urea in Salini-alkani Soil and Its Effect on Maize Yield

The paper aims to explore the enhancement of nitrogen use efficiency and yield- increasing mechanism with applying coated urea only once. A field plot experiment was conducted to study the effects of different coated urea and bare urea on maize yield and transformation of three types of coated urea in soil. The results showed that: compared with applying bare urea, the application of coated urea could inhibit the activity of urease in soil in the early maize growth period, the inhibition rate of treatment 3, 4, 5 was 27.06%, 28.36% and 39.50%, respectively; furthermore, the application of coated urea could slow down the release process of nitrogen fertilizer in soil to make sure enough nitrogen release in the later maize growth period; and after the heading stage, the content of soil alkaline hydrolyze nitrogen of treatment 3, 4, 5 was 40.33%, 66.64% and 53.89% higher than that of the control treatment (bare urea), meanwhile, the application of slow-release coated urea could also significantly improve the grain yield of maize; treatment 4 (2# coated urea) had the best yieldincreasing effect, under which the yield increased by 26.87% compared with that of the control treatment; thenitrogen partial factor productivity, nitrogen agronomy efficiency and nitrogen use efficiency increased by 13.13 kg grain/kg N, 6.76 kg grain/kg N and 10.33% , respectively, compared with those of the control treatment.