A laboratory experiment was carried out to examine the influence of nitroge
n (N), phosphorus (P), and potassium (K) application on the various fractio
ns of soluble plus exchangeable (EX), weakly specifically adsorbed (SA), ir
on-manganese (Fe-Mn) oxides bound (OX), organic matter complexed (OM), and
residual (RES) copper (Cu) and zinc (Zn) in a red soil (Typic Udic Ferrisol
s). Application of urea at rate of 200 mg N kg(-1) significantly decreased
the EX fraction, but increased the SA and/or OX fractions of both metals. S
upply of 80 mg P kg(-1) caused a decrease in the EX fraction, and a rise in
the SA fraction of Cu. However, the EX fraction of Zn was increased, but t
he OX fraction decreased by P supply. Addition of 100 mg K kg(-1) led to an
increase in the EX fraction, while a decrease in the SA and/or OX fraction
s of the metals. Applying chemical fertilizers had no significant influence
s on the other fractions of metals. These findings suggest that in heavy me
tal contaminated soil applying fertilizers does not only provide plant nutr
ients, but may also act to change the speciations and thus bio-availability
of heavy metals.