The Effect Of Saline Water Irrigation On Salt And Water Distribution, Soil Physical Properties And The Growth Of Seed Maize

Based on the current situation of the water shortage and implementation of water-saving irrigation in arid regions of northwestern China, field experiments conducted in 2013 and 2014 to study the effects of saline water irrigation on salt and water distribution, soil physical properties and the growth of seed maize in the Shiyang River basin. The main contents and finding of this research are as below:(1) The salt and water distribution in the soil under saline water irrigation was influenced by soil texture and the irrigation water salinity. With the increase of soil depth, soil texture changed, the soil moisture distribution had obvious stratification:low at the surface and high in the deep layer. Saline water irrigation resulted in a certain degree of salt accumulation in the soil of each layer, and the soil salinity increased with irrigation water salinity.(2) Saline water irrigation caused changes in basic soil physical properties, including soil bulk density, porosity and saturated hydraulic conductivity; along with the increase in number of saline water irrigation, soil bulk density increased, while soil porosity and saturated hydraulic conductivity decreased; the changes grew with the salinity increase. The saturated hydraulic conductivity has a close relationship with soil bulk density and porosity. Soil saturated hydraulic conductivity decreased with the increase of soil bulk density, and increased with the increase of soil porosity.(3) Saline water irrigation had a certain effect on soil texture. On one hand, saline water irrigation made partial soil clay disperse; on the other hand, the clay content increased.(4) Saline water irrigation had a great influence on the growth and yield of seed maize. The higher salinity of the irrigation water, the greater effect on the growth and yield of seed maize. Comparing with the fresh water irrigation treatment SO, heights of the seed maize under S9, S6, S3 treatments were reduced by 19.0%,11.5% and 2.5%; LAI were reduced by 46.3%,40.9% and 23.3%; yields were reduced by 48.2%,44.6% & 43.4%in 2013. Comparing with the SO fresh water irrigation treatment, heights of the seed maize under S9, S6, S3 treatments were reduced by 16%,13% and 10%; LAI were reduced by 24.1%,18.1% and 4.1%; yields were reduced by 32.8%,29.1%and 23.2% in 2014. While the irrigation water salinity is over 3g/l, saline water irrigation had a great impact on growth of seed maize; below 3g/l, the impact of saline water irrigation is relatively small. To ensure the growth and yield of seed maize, the irrigation water irrigation should not exceed 3g/l.