Effects of irrigation with saline water on soil salinity and crop yield

As freshwater is increasingly becoming a short of resource, it is impending to seek other substitute water (resource) for agriculture. A kind of saline groundwater with degree of mineralization (DOM) at 2 g/L to 5 g/L in 1020m underground layer was largely distributed at some of regions in Huang-huai-hai Plain, and these water were great (potential) resources for agricultural utilization. However, it is an urgent key research project to be studied how to use these saline water safely and effectively at present. The effects of saline water irrigation and combination with straw mulch on soil salinity and crop yield were studied at mini-plot under winter wheat-summer corn double cropping system in Northwestern Low Plain of Shandong Province. The results indicated that irrigation with DOM at 3g/L5g/L saline water for two years in spring did not increased soil salinity. Salt from irrigated saline water could be leached by integrated fresh-saline water irrigation and rain, so that total salinity in 1 m soil layer could be balanced annually. Wheat straw mulch could improve soil salt vertical distribution in that salinity within 040cm soil layer maintained in a lower salt level which reduce (degree) of salt damage to crop, and in turn, crop yield could be increased significantly. Two years mini-plot experiment (results) showed that irrigation with saline water cooperated with straw mulch had no significant difference on whole year crop yield compared to irrigation with fresh water, but resulted in yield decrease without straw mulch.