Abstract: This paper analyzed the effect of drip irrigation with brackish water with different salinities on the content of soil alkali-hydrolyzable nitrogen in rhizosphere of Ziziphus jujuba trees based on the experiment of irrigation with mixed salty water and fresh water. The results showed that the content of soil alkalihydrolyzable nitrogen in rhizosphere of Z. jujuba trees was increased with the increase of salinity of irrigation water when the migration and transformation time of soil alkali-hydrolyzable nitrogen was the same. The average value of soil alkali-hydrolyzable nitrogen content was increased at first and then decreased with the migration and transformation time of soil alkalihydrolyzable nitrogen when the salinity of irrigation water was the same. Under the same salinity of irrigation water, the change extent of soil alkali-hydrolyzable nitrogen content was in an increase trend, but the change rate was in a decrease trend. Based on analyzing the effect of irrigation brackish water with different salinities on soil alkali-hydrolyzable nitrogen content, the quantitative relationships among the salinity of brackish water and the migration and transformation time, average content, change extent and change rate of soil alkalihydrolyzable nitrogen were developed, and the regression equations were also derived in this study.

Key words: alkali-hydrolyzable nitrogen, salinity, brackish water, drip irrigation, rhizosphere of Ziziphus jujuba trees, effect model