Abstract: Contents of heavy metal elements of As,Cd,Co,Cr,Cu,Hg,Fe,Mn,Mo,Ni,Pb and Zn in soils of vegetable greenhouses 1,5,8 and 11 years old and a plot of conventional cultivated dryland(CK)have been investigated.The results showed that the content distributions of heavy metal elements within the soil layer(0-40 cm in depth)of the greenhouses of same age varied slightly;different heavy metal elements showed different tendencies in variation;generally,the contents of heavy metal elements in the soils of the greenhouses utilized for 5,8 and 11 years were higher,but not yet up to the extent of being called pollution;High rate of fertilization(compound fertilizers)is considered as the main reason for the increases in contents of heavy metal elements in the soils of these greenhouses.

Key words: vegetable greenhouse, soil, heavy metal, age of utilization, fertilization