干旱地区农业研究2017，Vol.35Issue(4)：80-87,8.DOI:10.7606/j.issn.1000-7601.2017.04.13
黄土塬区降水变化对冬小麦土壤耗水特性及水分利用效率的影响
Effects of rainfall fluctuation on water consumption and water use efficiency of winter wheat in the loess tableland
摘要
Abstract
A real-time rainfall control technique consisting of artificial rainfall-shields and gravitational trickle irrigation system was used to investigate the effects of normal rainfall (CK),rainfall reduction 1/3 (R-1/3),and rainfall increase1/3 (R+ 1/3)) on 0 ～ 4 m soil water storage,winter wheat water consumption and WUE in the loess tableland.The results indicated that:(1) Rainfall fluctuation modified water utilization of winter wheat and soil water supply.With the reducing of rainfall,winter wheat used more soil water,resulting in the decrease of deep soil water content during growth and fallow periods,which was hardly restored by rainfall during fallow period.With the increase of rainfall,deep soil water content decreased during growth period but could be restored even higher than initial soil water content after harvest due to the supply of rainfall in fallow period.(2) Winter wheat used soil water that transformed from current rainfall event firstly and then used early soil water.For evapotmnspiration(ET) of the period from overwintering to mature period,winter wheat of R-1/3 used more soil water from 0 to 2 m.Precipitation(P) and △W0～2 m each accounted for about 40％ of the ET.The ratio which P accounted for in ET of R+ 1/3 was about 1 times more than AWo～2 m· However,in the treatment of CK,The proportion which P accounted for in ET was about 15％ more than △W0-2m.Under the condition of rainfall decrease,the proportion of soil water transformed from current rainfall event to winter wheat water consumption decreased and the proportion of 0～ 2 m early soil water increased.Opposite result was obtained with rainfall decreasing.(3) Campared with CK,the winter wheat WUEbio(on biomass level) decreased by 1.3％ in the treatment of R-1/3,and its WUEgran(on grain level) increased,because the decline on grain level(7.1％) was less than the degree of water drops(14.2％).The winter wheat biomass decreased by 5.3 ％ and grain yield increased by 4.5 ％ in the treatment of R+1/3 when it was harvested,but its WUEbio and W UEgrain decreased because of 11.4％ increase in soil water conumption.Generally,rainfall fluctuation had effects on soil water use,soil water supply,winter wheat water consumption composition and the balance between biomass and grain of winter wheat,which affected the winter wheat WUE finally.关键词
土壤水/降水变化/水分利用效率/冬小麦/耗水特征Key words
soil water/rainfall fluctuation/water use efficiency/winter wheat/water consumption分类
农业科技引用本文复制引用
倪盼盼,朱元骏,巩铁雄..黄土塬区降水变化对冬小麦土壤耗水特性及水分利用效率的影响[J].干旱地区农业研究,2017,35(4):80-87,8.基金项目
国家自然科学基金(41371242,41530854) （41371242,41530854）
中国科学院“西部之光”和中国科学院重点部署项目(KFZD-SW-306) （KFZD-SW-306）
