The Synergetic Effect of Soil Amendments on Reducing Bioavailable Heavy Metals and Greenhouse Gas Emissions from Upland Soil

Heavy metal pollution and greenhouse gas (GHG) emissions from soil are two major detrimental sources in the agriculture environment because of concerns about crop safety and global warming. Applying amendments on site is a common technique used for heavy metal remediation and the reduction in GHG emissions. This study aims to evaluate the effect of different amendments on the reduction in both bioavailable heavy metals and GHG emissions from soil. Four different amendments, namely bottom ash (BA), sintered material (SM), sintered material combined with lime (SM + L), and FeO (SM + FeO) were applied to upland fields, followed by maize ( Zea mays L.) cultivation from April to October. Subsequently, SM + FeO treatment demonstrated the highest bioavailability reduction efficiency for As at 79.1%, and SM + L treatment had a high efficiency for the reduction in Cd and Pb by 64.6% and 41.4%, respectively. SM + FeO treatment also reduced bioaccumulated As and Pb in maize grain by 59.3% and 66.2%, respectively. Furthermore, SM + FeO treatment demonstrated the highest reduction efficiency for cumulative N 2 O emissions by 70.7%, compared to the control soil. Among the four different amendments, the efficiency of heavy metal and GHG emission reduction was in the following order: SM + FeO > SM + L > SM > BA. Overall, SM combined with FeO is a promising amendment for reducing and managing both heavy metal pollution and GHG emissions in soil.