Effects of Irrigation Volume and Ridge Height on Water-Salt Transport in Secondary Saline-Alkali Soil and Maize Yield

Zhu Xudong; Jiao Bingzhong; Wu Huifang; Shi Suqi

doi:10.14083/j.issn.1001-4942.2024.09.020

Abstract：In order to address the challenges of rising groundwater level and secondary salinization caused by prolonged surface irrigation in Ningxia Yanghuang irrigation district,a designated experimental area-was selected from Hongsibao of Ningxia,and the location test monitoring was carried out.Two factors with three levels were set as irrigation volume at 2 160,2 700 and 3 240 m3·hm-2 and ridge height at 20,30 and 40 cm under efficient drip irrigation.The water and salt movement patterns in secondary saline soil under dif-ferent combination processings and their effects on maize growth indicators,yield and water use efficiency(WUE)were studied through field experiment.The results indicated that the moisture content in 0～60-cm soil layer decreased with ridge height increasing at a constant irrigation quota,while it increased with irrigation vol-ume increasing at a constant ridge height,and the deeper the soil layer was,the higher the moisture content was.Ridge drip irrigation could reduce soil salinity on ridges effectively,while varying degrees of salt accumulation oc-curred in deeper soil layers in all treatments,among which,T9 treatment(combination of 3 240 m3·hm-2 and 40 cm)showed the most obvious in salt accumulation in the 40～60-cm soil layer.In T6 treatment(combination of 2 700 m3·hm-2 and 40 cm),both the growth indicators and yield were superior to those in the other treat-ments,and the yield was up to 6 597.15 kg·hm-2.In T5 treatment(combination of 2 700 m3·hm-2 and 30 cm),the WUE achieved the highest level of 1.53 kg·m-3.Regression analysis revealed that the irrigation vol-ume and ridge height were different when the maize yield and WUE at their maximum values.Spatial analysis further indicated that both maize yield and WUE reached 90％of the maximum values when the irrigation vol-ume was 2 685～2 730 m3·hm-2 and the ridge height was 36～39 cm.