Effects of Water Management on Greenhouse Gas Emissions and Phytoremediation
Water management plays an important role in soil greenhouse gas emission and phytoremediation of soil contaminat-ed by heavy metals.In this study,the hyperenriched plant Pterocypsela indica was selected as the research object to investigate the effects of 55%water holding capacity(55%WHC)and 75%water holding capacity(75%WHC)on soil greenhouse gas emis-sions and phytoremediation.The results showed that compared with 55%WHC treatment,75%WHC treatment significantly increased the stress resistance of P.indica,and 75%WHC treatment increased the aboveground Pb content and accumulation of P.indica by 92.3%and 91.0%,respectively.Compared with 55%WHC treatment,75%WHC treatment reduced cumulative green-house gas emissions,and soil CO2 cumulative emissions were reduced by 18.8%and 10.0%,and N2O cumulative emissions were reduced by 9.1%and 47.0%,respectively,under the two conditions of planting and no planting of P.indica.Cumulative CH4 emis-sions were reduced by 17.1%and 43.7%,respectively.In conclusion,compared with 55%WHC,75%WHC treatment can promote the growth and accumulation of heavy metals,reduce greenhouse gas emissions,and is more suitable for phytoremediation.