Abstract: In order to study the changes of content of heavy metals in the soil and navel orange fruits after application of different types of fertilizers, the contents of Cr, Cu, Pb, Zn, Cd and As were measured and the correlation analysis was carried out after the application of organic manure, chemical fertilizer and biogas waste fertilizer in 1997 and 2002. The results showed that the As content in 2002, and the Cu and Pb contents in 1997 were increased significantly by application of organic manure in the soil. Similarly, the Pb content in 2002 were significantly increased by application of biogas waste fertilizer. Only the heavy elements of As and Cu showed significant difference (P<0.05) in the navel orange fruits as compared to the control. The order of the As accumulation was organic manure>chemical fermical>biogas waste fertilizer, and the Cu accumulation order was chemical fermical>organic manure=biogas waste fertilizer. There was no significant difference of heavy metal contents of the soil and navel orange fruits in 1997 and 2002. All heavy elements did not exceed the limitation of related standard in the soil and navel orange fruits. The correlation analysis showed that there were significant positive correlation between Cu and Zn in the soil and navel orange fruits (R2>0.9), whereas there was no significant relathionship among As,Cr,Pb,Cd (R2<0.7)．

Key words: heavy metals, soil, navel orange, correlation analysis