Cu and Pb accumulation in maize (Zea mays L.) and soybean (Glycine max L.) as affected by N, P and K application

Abstract

Nitrogen (N), phosphorus (P) and potassium (K) fertilizer application affects soil properties and processes in
many ways that remain unclear. The effects of N, P, and K application on plant growth and copper (Cu) and lead
(Pb) accumulation, as well as their differences in plant species were thus evaluated in soil- maize and soilsoybean systems. Five treatments were arranged: N, P, and K application (NPK), N and P application (NP), N
and K application (NK), P and K application (PK), and CK (no fertilization). Results showed that N application
could significantly increase maize shoot Cu concentration and translocation from soil to above ground tissue
(p<0.05). However, soybean shoot Cu concentration could not increase with N application. Phosphorus
application could effectively decrease the bioavailability of Cu and Pb in both systems. Under nutrients
deficiency, soil dissolved organic carbon (C) significantly increased, showing difference in plant species
(p<0.05), which further enhanced Cu and Pb mobility in soils. Copper removal from soil positively correlated
with plant biomass production with the NPK and NP treatments showing the greatest in both crops. Our results
show that, an appropriate increase in P application and decrease in N application are recommended to reduce
agro-ecological risks associated with Cu and Pb in soil-plant systems.