Effect of saline water irrigation on yield and water-nitrogen productivity in maize and wheat in China:A Meta-analysis
HE Xuezhong
JIA Zhenjiang
WU Yangyang
WU Xiu
LI Bin
XU Haowen
LI Wangcheng
Abstract：[Objective]China is facing increasing freshwater scarcity,and saline water has been increasingly used as a supplementary resource for crop production.However,its long-term impact on crop yield and resource use efficiency remains unclear.This study aims to investigate the influence of irrigation water quality,initial soil condition,agronomic management,and environmental and climatic factors on grain yield and water-nitrogen productivity of maize and wheat under saline irrigation.[Method]A meta-analysis based on 834 pairs of field observations was conducted to quantitatively assess the responses of grain yield,water productivity(WP),irrigation water productivity(IWP),and nitrogen productivity(NP)to saline water irrigation.The relationships between these responses and irrigation water electrical conductivity(EC),as well as the duration of saline irrigation,were analyzed.[Result]Compared with freshwater irrigation,saline water irrigation significantly(P＜0.05)reduced grain yield,WP,IWP,and NP in maize and wheat by 24.94%and 18.60%,7.20%and 9.04%,20.70%and 15.35%,and 20.34%and 14.95%,respectively,indicating that maize is more sensitive to saline irrigation than wheat.However,these responses varied markedly with irrigation water properties,soil condition,management practices and environmental conditions.Higher yields were generally achieved under short-term saline irrigation with a sodium adsorption ratio in the range of 10 to 18,combined with reduced nitrogen application,moderate irrigation amount,and surface mulching.These effects were particularly evident in alkaline soils with high bulk density,coarse texture,low salinity,and high organic matter content,especially in arid and cold regions where the groundwater table is deep.In addition,increasing nitrogen application in medium-textured soils enhanced WP.Subgroup and regression analyses indicated a clear time-lag effect of saline irrigation duration on WP,IWP and NP,whereas grain yield decreased linearly with increasing duration of saline irrigation.The optimal EC thresholds for saline irrigation water were identified as 3.57-5.77 dS/m for maize and 2.51-4.64 dS/m for wheat.[Conclusion]Saline water irrigation generally reduces crop performance;however,its negative effects can be mitigated through optimized agronomic practices and coordinated management of irrigation water quality,soil condition,and groundwater depth.These findings provide practical guidance and scientific support for improving saline water irrigation in maize and wheat production in China.
Keywords：saline water irrigationmaizewheatyieldwater-nitrogen productivityMeta-analysis
Publication Date：2026-06-30
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：8( 50-57 )