不同肥料运筹对夏玉米田间土壤氮素淋溶与挥发影响的原位研究

In situ study on influence of different fertilization strategies for summer maize on soil nitrogen leaching and volatilization

运用排水采集器法和通气法结合田间原位试验，研究了不同肥料运筹对夏玉米田间土壤氮素淋溶与挥发的影响。结果表明，在夏玉米生长季节，田间土壤水分淋溶体积达63．4～97L／hm^2，且表现与灌溉水量和降雨量正相关。与单施氮肥相比，有机肥配施氮肥在夏玉米生长发育前期易加剧水分的淋溶；氮素淋溶损失量明显高于氨挥发损失量，且二者均随施氮量的增加而升高；与单施氮肥相比，有机肥配施氮肥极显著地增大了氮素淋失量，减少氮素的氨挥发损失量，总体分析显示，有机肥配施氮肥极显著增大了氮素净损失量和氮素损失率；在夏玉米生长期内，施肥运筹的田间土壤淋溶水硝态氮浓度均呈现“双峰”趋势，以硝态氮形式淋失是田间土壤氮素淋失的主要形式。铵态氮浓度则呈现先升后降的趋势，铵态氮的累计淋失量很少。同时发现，大口期夏玉米生长旺盛，对氮素的需求强烈可以减少氮素的淋失和氨挥发损失，适量增加夏玉米大口期的追肥量，是提高氮肥利用效率的有效途径。

In situ experiments co fertilization strategies on nitrogen maize. The intensity of in the maize mbining field lysimeters and venting method were used to leaching loss and ammonia volatilization from soil during study the influence of different the growing season of summer major season of nitrogen leaching was rainy season during the growing season of summer maize, with strong rainfall in the Huanghuaihai region. Both irrigation and rainfall affected the volume of water leaching from soil field. The obtained results showed that the volume of water leaching was 63.4-97 L/ha in the period of summer , which had positive correlation with the amounts of irrigation water and rainfall. Compared with single nitrogen fertilizer, organic manure combined with nitrogen fertilizer facilitated water leaching and ammonia volatilization were the major nitrogen losing ways in dryland leaching from in field. Both nitrogen farming system. The accumulative total nitrogen leaching was obviously more than the accumulative total ammonia volatilization in the period of summer maize growth, and both increased concomitantly with nitrogen application rate. Compared with single nitrogen fertilizer, organic manure combined with nitrogen fertilizer significantly increased the accumulative total nitrogen leaching, and reduced the accumulative total ammonia volatilization. Overall, organic manure combined with nitrogen fertilizer markedly increased the accumulative total amount and rate of nitrogen loss in the period of summer maize growth. The density of NO3^--N in water leaching had two peaks, while the density of NH4^＋-N increased first and then decreased. The results also indicated that increasing N application at the rapid growth stage can reduce N leaching and volatilization, and is an effective approach to increasing nitrogen use efficiency.