Effect of mulch-drip irrigation on soil enzyme activities of saline-sodic soil with shallow water table

In order to know the effects of mulch-drip irrigation on soil enzyme activities of saline-sodic soil with shallow water table, activities of alkaline phosphatase, urease, and invertase around the dripper, within 30 cm in horizontal direction and 40 cm in vertical direction from the dripper during the reclamation process, were investigated. Changes and distribution of soil enzyme activities, also their relationships with principal soil environment factors were studied. The results showed that activities of alkaline phosphatase, urease and invertase were promoted with time as the saline-sodic soil being reclaimed. Activities of the three enzymes around the dripper increased during the irrigation period and decreased as irrigation ceased in both horizontal and vertical directions. Furthermore, distributions of soil enzyme activities which decreased radially from the dripper in soil profiles were like ellipses. Correlation analysis showed that after two years of irrigation, relationships between soil enzyme activities and principal soil environment factors, also the relationship between soil enzymes, increased. Therefore, reclamation of saline-sodic soils by mulch-drip irrigation could promote soil enzyme activities, ameliorate soil environment and provide plants a good growth condition.