摘要
为探讨不同滴灌施氮策略对玉米生长、产量、水肥利用效率的影响,于2015年在河套灌区开展了玉米膜下滴灌田间试验。试验设置3个灌水水平（采用张力计指导灌溉,分别控制滴头正下方20cm深度处土壤基质势下限高于-20,-30,-40kPa）,6个施氮水平（0,180,225,262.5,300,345kg/hm2）,研究水氮互作对玉米株高、LAI、产量、水氮利用率的影响。结果表明,在玉米生育期前期,高氮对玉米株高与叶面积指数（LAI）具有明显的促进作用,在灌浆期,受水氮互作以及施氮量的影响,随施氮量的增大表现出先升高后降低的趋势,当施氮水平为N3（262.5kg/hm2）时为最大。完熟期玉米干物质积累对灌水的响应表现为：W1（-20kPa）〉W2（-30kPa）〉W3（-40kPa）,施氮对玉米籽粒吸氮量的变化表现为：N3（262.5kg/hm2）〉N4（225kg/hm2）〉N2（300kg/hm2）〉N5（345kg/hm2）〉N0（0kg/hm2）,N3比N1和N2分别升高15.71%和11.13%,比N4仅提高1.51%。灌水与施氮均可显著增加玉米籽粒产量、百粒重、穗行数以及行粒数,二者有显著的交互作用,且以氮为主效应。在施氮0~262.5kg/hm2范围内,氮肥利用率随施氮量的增加而升高,此后反而降低;在该范围内水分利用效率以及灌溉水利用效率均随施氮量升高而增加,随基质势控制水平的升高而明显下降,以灌水水平W3（-40kPa）为最大。在试验中,以W3N3处理的水氮利用率最高,其水分利用效率与氮肥回收率比产量最高的W2N4要分别高出1.93%和76.60%,但产量比W2N4要下降约8.58%。在河套灌区玉米膜下滴灌施氮条件下,灌水量-30kPa和施氮量225kg/hm2时,可获得最高的籽粒产量。在灌水量-40kPa和施氮量262.5kg/hm2条件下,可以获得低于最高籽粒产量约8%的籽粒产量与最高的水氮利用率。从节水和生态可持续发展角度来看,灌水水平W3（-40kPa）、施氮水平N3（262.5kg/hm2）为当地最佳的滴灌施氮策略。
Optimizing regulation irrigation schedule,rates and coupling with N fertigation was an effective way for realizing crop production improvement as well as water and nutrient use efficiency enhancement.The effects of dripirrigation frequency（which controlled soil matric potential at 0.2mdepth immediately under drip emitters controlled higher than-20,-30and-40kPa）and nitrogen fertilizer level（0,180,225,262.5,300 and 345kg/hm2）on the maize grain yield,water use efficiency and nitrogen use efficiency were studied by the means of using a split plot experiment with two factors.There was an obvious tendency that the plant height and LAI of maize increased with levels of water,but those decreased when the N applied rate beyond 262.5kg·hm-2.The response of dry matter weight of maize in harvest time to irrigation water was：W1（-20kPa）W2（-30kPa）W3（-40kPa）.The effects of nitrogen fertilizer amounts on the amount nitrogen of seed in maize in harvesting dates was：N3（262.5kg/hm2）N4（225kg/hm2）N2（300kg/hm2）N5（345kg/hm2）N0（0kg/hm2）.Both irrigation and N supply exerted a significant role on maize yield as well as yield component of kernels per row and 100 grain weight.An obvious positive interaction wasobtained between water and nitrogen.Moreover,the effect of N on yield was substantially higher than that of irrigation.N fertilizer use efficiency increased with increasing N level within N supply range of 0~262.5kg/hm2,and then dropped markedly when N rate above 262.5kg/hm2.And in this range,it was found that the water use efficiency（WUE）and irrigation water use efficiency（IWUE）increased with increasing N level,while that decreased with increasing irrigation rate.At the suitable irrigation level of W3,the WUE,IWUE of 42.20~49.23kg/mm and 63.31~78.00kg/mm could be achieved.The highest yield was obtained in the combination treatments of W2N4 with the value of 20 489.06kg/hm2.W3N3 combination treatment had the highest WUE,NRE and the yield could achieve 18 730.62kg/hm2,which decreased
出处
《水土保持学报》
CSCD
北大核心
2016年第5期149-155,共7页
Journal of Soil and Water Conservation
基金
内蒙古自治区水利科技重大专项([2014]117)
国家自然科学基金(51469020)
关键词
水氮耦合
膜下滴灌
水氮利用率
玉米
water coupling with nitrogen
mulched drip-irrigated
water use efficiency
N fertilizer use efficiency
maize
