Abstract: The rule and mechanism that total organic carbon, clay content and soil water content affected PHEs’ vertical distribution and migration were shown by testing and analyzing soil samples from vadose zone and aquifer in the typical environment district-Zhangshi irrigated area. The research of representative sampling spots indicated that the tend of the total content of PHEs decreased generally with the depth of the profile section; while that of upper soil varied slowly from 5 cm to 20 cm beyond the plough pan.Then,the relationship between PHEs and total organic carbon, clay content and water content was analyzed separately by two variable correlation analysis, and the findings calculated by Pearson coefficient demonstrated that the total organic carbon, clay content were the important factors influencing the PHEs’ vertical distribution and migration, but soil water content was neglected. SPSS factor analysis is further used to ensure that total organic carbon is the key factor which limits the PHEs vertical distribution.

Key words: Zhangshi irrigative area, phenanthrene (PHEs), total organic carbon (TOC), clay content, soil water content, vertical distribution and migration