On the basis of 25-year study on long-term located experiments of fertilizer

analysis is made on he change tendency of heavy-metal content in soil of 0~20 cm which are treatd with six different fertilization trails detailed as fertilizing by N

NP

NPK

N organic fertilizer

N straw and no fertilizer. The result states that: All 6 elements present trend of increasing. The Zn content of the soil with N organic fertilizer processed

which exceeds the limit of the Soil Environmental Quality Standard II

Hg content increased massively

114% increased than the testing foundational value. No weighty effect to the soil only N fertilizer (urea) used

use P fertilizer shall increase the heavy-metal content of the soil. The organic fertilizer

which takes rejected materials of livestock and poultry as raw materials

shall increase the heavy-metal content of the soil

Cu

Zn and Hg increased especially. The organic fertilizer

which takes rejected materials of livestock and poultry as raw materials

should be used reasonably

fertilization is an important reason to effect the change of heavy-metal in soil.