Effects of Planting Patterns on Trace Metals in Soils Following Wetland Restoration

Abstract

To understand the effects of planting patterns on trace metal fractions in degraded wetland soils in the Jinjiang Estuary, the chemical speciation of trace metals (Cu, Cr, Zn, and Pb) before and after wetland restoration is analyzed based on a measurement and testing program. The results show that wetland restoration, in general, increases the ratios of Cu, Cr, Zn, and Pb in the acid‐soluble fraction and the ratios of Cr, Zn, and Pb in the residual fraction and decreases the ratios of Cr, Zn, and Pb in the reducible fraction and the ratios of Cu, Cr, Zn, and Pb in the oxidizable fraction; thus, the mobility of Cu increases, and the mobility of Cr, Zn, and Pb decreases. Moreover, the planting patterns influence the levels of Cu, Cr, Zn, and Pb to some extent. After wetland restoration, the levels of Cu show an upward trend, and the Pb levels exhibit a downward trend. However, the potential ecological risk of Cu, Cr, Zn, and Pb fail to decrease. The restoration time may have been too short. The results of this study indicate that the planting patterns influence the transformation of trace metal fractions in soil and affect the pollution degree and potential ecological risk, contributing to a better understanding of the effects of planting patterns on trace metals following wetland restoration. The results will be helpful for subsequent scientific research on wetland restoration.