The field experiments were conducted at Yuli county of Xinjiang in 2004 from Apr. to Oct. It is tound that in south Xinjiang

in cotton seedling stage

because of covering the function of the membrane

the salt in soil begin the dividing area

the salt is gathered strongly in 0-20 cm in uncovered area

and the salt of soil under film had taken place side direction transport and move to the uncovered area which have aggravated the salt of uncovered area even more. After cotton growing stage finishing

the salt of 0- 60 cm layers have increased

and assembled sharply in the uncovered area in 0-20 cm layers; The salt of lower water treats enhanced greater

the ration of salt accumulation reached 94.5%

which mainly come from the salt that moving up water carried on

up to 57 % of increased salt

and the salt increased of higher irrigation treats mainly come from the salt irrigation water carrying on

was about 81%

so adding irrigating water can decreased the accumulation of salt in a certain extent.