不同缓控释氮肥对连作春玉米产量及氮肥去向的影响

Effects of Different Slow Controlled-Release Fertilizers on Grain Yield and Nitrogen Fate in Continuous Spring Maize Production

在山西省连作春玉米区连续4年设置大田定位试验,设置不施氮肥(CK)、一次性基施尿素(CU1)、追施尿素(CU2)、树脂包膜尿素(PCU)、硫包衣尿素(SCU)、多酶金缓释尿素(MEU)6个施肥处理,研究施用缓控释氮肥对春玉米产量、氮肥去向及氮素平衡的影响,为春玉米氮素养分的科学管理技术提供参考。结果表明:(1)缓控释氮肥处理能够明显提高春玉米产量,促进氮素吸收。与CU1处理相比,SCU、MEU、PCU和CU2处理可分别提高春玉米产量17.51%,9.88%,9.62%,9.48%,同时氮肥农学利用效率分别提高7.5,4.2,4.1,4.1 kg/kg。(2)不同缓控释氮肥处理的作物吸收肥料氮以及肥料氮在0-100 cm土层残留量之间存在显著差异。SCU、MEU、PCU、CU2和CU1的氮肥表观利用率分别为36.1%,32.5%,26.5%,26.7%,19.5%,肥料氮在0-100 cm土层残留量分别占施氮量的28.5%,31.6%,35.7%,35.5%,39.1%。此外,与一次性基施尿素相比,缓控释氮肥能够显著降低肥料氮的损失,SCU、MEU、PCU和CU2分别降低了22.65%,18.81%,8.99%,8.47%。(3)综合分析不同氮肥处理的农田氮素平衡,SCU处理的春玉米吸氮量最高,为261.5 kg/hm^2,其次是MEU,为253.5 kg/hm^2。SCU的0-100 cm土层残留量在缓控释氮肥中最低,为124.1 kg/hm^2,MEU和PCU分别为131.04,140.09 kg/hm^2。SCU处理的氮表观损失量最低,为106.3 kg/hm^2,MEU和PCU分别为111.6,125.1 kg/hm^2。在山西省春玉米主产区土壤上,缓控释氮肥能够显著促进春玉米对氮素的吸收,减少氮素损失。硫包衣尿素和多酶金缓释尿素的效果相对较好。

A field positioning experiment was conducted in spring maize continuous cropping area of Shanxi Province for four consecutive years, which included six fertilization treatments: No application of nitrogen fertilizer(CK), one-time basal application of urea(CU1), topdressing of urea(CU2), resin coated urea(PCU), sulfur coated urea(SCU) and multi-enzyme gold sustained-release urea(MEU). It was set up to study the effects of slow controlled release nitrogen fertilizers on spring maize yield, consumption of nitrogen fertilizer and nitrogen balance to provide reference for scientific management technology of spring maize nitrogen nutrition. The results showed that:(1) Slow controlled release nitrogen fertilizer treatment could significantly increase spring maize yield and promote nitrogen uptake. Compared with CU1, SCU, MEU, PCU and CU2 increased the yield of spring maize by 17.51%, 9.88%, 9.62% and 9.48%, respectively, while the agricultural utilization efficiency of nitrogen fertilizer was increased by 7.5, 4.2, 4.1 and 4.1 kg/kg, respectively.(2) There were significant differences in the uptake of fertilizer nitrogen by crops and the residual amount of fertilizer nitrogen in 0-100 cm soil layer with different fertilizers. Apparent use efficiency of nitrogen of SCU, MEU, PCU, CU2 and CU1 were 36.1%, 32.5%, 26.5%, 26.7% and 19.5%, respectively. Residual fertilizer nitrogen in 0-100 cm soil layer accounted for 28.5%, 31.6%, 35.7%, 35.5% and 39.1% of the nitrogen application, respectively. Additionally, compared with one-off urea application, slow controlled release nitrogen fertilizer could significantly reduce the loss of fertilizer nitrogen, by 22.65%, 18.81%, 8.99% and 8.47% for SCU, MEU, PCU and CU2 respectively.(3) Comprehensive analysis of nitrogen balance in different treatments showed that the SCU had the highest nitrogen uptake, 261.5 kg/hm^2, followed by MEU, 253.5 kg/hm^2. The residues amount in 0-100 cm soil layer in SCU was the lowest among the slow controlled release nitrogen fertilizer treatments, 124.1 kg/hm^2, and 131.04 kg/hm^2 for MEU and 140.09 kg/hm^2 for PCU. The apparent loss of nitrogen in SCU was the lowest, 106.3 kg/hm^2, and 111.6 kg/hm^2 for MEU and 125.1 kg/hm^2 for PCU. In the soil of main spring maize producing areas in Shanxi Province, slow controlled release nitrogen fertilizer could significantly promote the absorption of nitrogen and reduce nitrogen loss. Sulfur coated urea and multi-enzyme gold sustained-release urea have relatively good effects.