Pot experiment in outdoors was conducted by comparing 5 kinds of poplar(P.liaoyu 1

938-18

P.×gaixianensis

P.liaoyu 3

and"P.simonii×P.euphratica"×P.sp) to search for suitable tree species which can be adopted in the Cd contaminated region.There was no significant difference between treatments for seeding height and basal diameter.Moreover

there was no significant difference between treatments for biomass of 938—18

P.×gaixianensis

and"P.simonii×P.euphratica"×P.sp.However

biomasses of P.liaoyu 1 and P.liaoyu 3 were affected significantly by Cd.At the Cd contamination level of 150 mg/kg

their biomasses were significantly decreased.At the level of 5 mg/kg

seedling's biomasses of P.liaoyu 1 and P.liaoyu 3 were the heaviest

so the lower Cd density may increase seedling's biomass and the higher Cd density may repress seedling growth.There was no influence on the amounts of roots of 938—18 and "P.simonii×P.euphratica"×P.sp

but Cd 2+in soil may activate rooting of the rest kinds of poplar.