The distribution patterns of Tamarix chinensis population under the environmental gradient of different water table depth were analyzed using two fractal analysis methods—box dimension and information dimension.The box dimension changed little with different water table depths and kept a high dimension

which means that Tamarix chinensis population may keep a high spatial possessive degree for different water table depth.However

the information dimension in general decreased with the decline of water table depth.When water table depth was below-1.55 m

the information dimension was large

indicating that in this section of water table depth gradient

the micro-structure of Tamarix chinensis population was much complex and the pattern intensity was high.When water table depth was above-1.55 m

the information dimension was generally very small

indicating that the micro-structure of Tamarix chinensis population was very simple and the pattern intensity was low.The water table depth of-1.55 m may be a threshold of the distribution patterns of Tamarix chinensis in wetlands of the Yellow River Delta.