根层调控对小麦-玉米种植体系氮素利用及土壤硝态氮残留的影响  

Effects of Root Layer Regulation on Nitrogen Utilization and Soil NO_3^--N Residue of Wheat-Maize System

作　　者：彭亚静[1,2] 汪新颖[1,2] 张丽娟[1,2] 郝晓然[1,2] 乔继杰 王玮[1,2] 吉艳芝[1,2] 

机构地区：[1]河北农业大学资源与环境学院/河北省农田生态环境重点实验室 [2]河北农业大学邸宏杰土壤与环境实验室,河北保定071000

出　　处：《中国农业科学》2015年第11期2187-2198,共12页Scientia Agricultura Sinica

基　　金：国家“十二五”粮食丰产科技工程(2011BAD16B08,2012BAD04B06,2013BAD07B05)

摘　　要：【目的】针对华北平原冬小麦-夏玉米轮作区高产田水肥资源利用效率低、氮素累积严重的问题,探索不同根层调控措施对作物氮素利用及土壤NO3--N残留的影响。【方法】以华北平原高产粮田为对象,设置传统水氮、水氮调控、调控+土壤调理剂(Agh)、调控+CRU(用含量为43%的缓释尿素代替氮肥)和调控+植物生长调节剂(GGR)田间小区试验,采集测定土壤、植株及根系样品,分析不同根层调控措施对氮素利用的效果。【结果】在控水减氮前提下,调理剂和GGR处理的小麦玉米周年产量、吸氮量均高于传统水氮。小麦拔节期GGR处理80—100 cm土层根系分布较多,表明GGR能促进中下层根系的发育;玉米大喇叭口期,藁城调理剂和大名GGR处理20—50 cm土层的根长密度均明显高于传统水氮。第一个轮作季,藁城和深州GGR的0—200 cm土体各土层硝态氮残留量均显著低于传统水氮,尤其在60—100 cm土层硝态氮的残留最低;第二个轮作季,藁城调理剂和大名GGR处理各土层硝态氮的残留量显著低于传统水氮。第一个轮作季的调理剂和第二个轮作季的GGR(藁城)的氮素表观亏缺量较大,说明根层调控促进了作物对土壤累积氮素的利用。根层调控措施能够达到经济和生态的双赢,灌溉水分利用效率(WUE)和氮偏生产力(PFPN)较传统水氮平均提高了2.47 kg·m-3和18.08 kg·kg-1,平均增收258.43元/667 m2。【结论】在华北平原高产田,不同根层调控措施的小麦、玉米单季及周年的产量较传统水氮平均分别提高了8.58%、5.99%和7.13%;两季作物收获后0—100 cm土层中土壤硝态氮残留量较传统水氮平均分别降低了70.73和59.44kg·hm-2,明显降低了土壤硝态氮的残留,减缓了向土体深层的淋溶损失;促进了小麦、玉米关键生育期根系的发育。总之,通过在控水减氮的基础上添加土壤调理剂和植物生长调节剂(GGR)可以显著提高作物产量,�【Objective】 Low resource utilization efficiency of water and fertilizer and high soil nitrogen accumulation were common problems of the winter wheat-summer maize system in the North China Plain.This study was conducted to investigate the effects of different root layer regulation measures on nitrogen utilization and soil NO3^--N residue of crops.【Method】 The field experiment was conducted in the high-yield farmlands in North China Plain.Traditional water-nitric nitrogen,water-nitric nitrogen regulation,regulation＋Agh（soil conditioner）,regulation＋CRU（controlled-release urea）,regulation＋GGR（plant growth regulator） were designed as five treatments.Soil,plant and root samples were collected and measured,and the nitrogen utilization effects of different root layer regulation measures were analyzed.【Result】The results indicated that under the premise of controlling water and nitrogen,the wheat-maize yield and nitrogen uptake in Agh and GGR treatments were higher than traditional water and nitrogen treatments.At jointing stage of wheat,roots at 80-100 cm soil layers in GGR treatment distributed much,which shows that GGR could promote the development of roots at lower layer.At bell stage of maize,at 20-50 cm layer,root length density of Agh treatment in Gaocheng and GGR treatment in Daming was significantly higher than those of traditional water and nitrogen treatment.In the first rotation season,in 0-200 cm layer,the soil residual nitrate-N in GGR treatment in Gaocheng and Shenzhou was significantly lower than that of traditional water and nitrogen treatment,especially at 60-100 cm layer soil residue nitrate nitrogen was the lowest.In the second rotation season,the soil residual nitrate-N in Agh treatment in Gaocheng and GGR treatment in Daiming were significantly lower than traditional water and nitrogen treatment.The amount of apparent deficiency of nitrogen of Agh in the first rotation season and GGR（Gaocheng） in the second rotation season was large,which indicate that root regulatio

关 键 词：根层调控 小麦-玉米轮作 产量 NO3--N残留 土壤调理剂 植物生长调节剂 

分 类 号：S513[农业科学—作物学] S512.1