Metal release/accumulation during the decomposition of Potamogeton crispus in a shallow macrophytic lake  

作　　者：Huanguang Deng Ju Zhang Shiyue Chen Liwei Yang Dongqi Wang Shiyong Yu 

机构地区：[1]School of Environment and Planning,Liaocheng University [2]School of Geographical Sciences,East China Normal University [3]Institute for Cultural Heritage,Shandong University

出　　处：《Journal of Environmental Sciences》2016年第4期71-78,共8页环境科学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.41401563,41301544,41201094);the Natural Science Foundation of Shandong Province(Nos.ZR2014JL028;ZR2012DQ003);the China Postdoctoral Science Foundation(No.2015M571830);the Taishan Scholar Program of Shandong Province for supporting his research

摘　　要：Changes in metal concentrations in the litter of Potamogeton crispus were monitored during a consecutive 40-day in situ decomposition experiment using the litterbag method.The accumulation index was calculated and used to indicate the changes in the metals in litter.The results showed that the concentrations of Al,Cd,Cr,Fe,Mn,and Pb in litter increased significantly during the decomposition,while Cu and Zn concentrations decreased dramatically.Significant positive correlations were found between the concentrations of Al,Cr,Fe,and Mn and between Cu and Zn.Moreover,Cu and Zn both negatively correlated with Al and Fe.The remaining dry mass was negatively correlated with Al and Fe concentrations but positively correlated with Cu and Zn concentrations.Generally the accumulation index values of metals other than Al were less than one,indicating that the litter of P.crispus acted as a source of metals to the surrounding water body.Al was the only metal that showed continuous net accumulation in litter.The net accumulation of Fe and Mn in litter during the last 10 days of the experiment may indicate the precipitation of Feand Mn-oxides.It was estimated that 160 g/m^2（dry weight）P.crispus was decomposed in40 days.This was equivalent to releasing the following amounts of metals：0.01 mg Cd,0.03 mg Cr,0.71 mg Cu,0.55 mg Mn,0.02 mg Pb and 13.8 mg Zn into surrounding water,and accumulating 149 mg Al and 11 mg Fe,in a 1 m^2 area.Changes in metal concentrations in the litter of Potamogeton crispus were monitored during a consecutive 40-day in situ decomposition experiment using the litterbag method.The accumulation index was calculated and used to indicate the changes in the metals in litter.The results showed that the concentrations of Al,Cd,Cr,Fe,Mn,and Pb in litter increased significantly during the decomposition,while Cu and Zn concentrations decreased dramatically.Significant positive correlations were found between the concentrations of Al,Cr,Fe,and Mn and between Cu and Zn.Moreover,Cu and Zn both negatively correlated with Al and Fe.The remaining dry mass was negatively correlated with Al and Fe concentrations but positively correlated with Cu and Zn concentrations.Generally the accumulation index values of metals other than Al were less than one,indicating that the litter of P.crispus acted as a source of metals to the surrounding water body.Al was the only metal that showed continuous net accumulation in litter.The net accumulation of Fe and Mn in litter during the last 10 days of the experiment may indicate the precipitation of Feand Mn-oxides.It was estimated that 160 g/m^2（dry weight）P.crispus was decomposed in40 days.This was equivalent to releasing the following amounts of metals：0.01 mg Cd,0.03 mg Cr,0.71 mg Cu,0.55 mg Mn,0.02 mg Pb and 13.8 mg Zn into surrounding water,and accumulating 149 mg Al and 11 mg Fe,in a 1 m^2 area.

关 键 词：Litter decomposition Metal release/accumulation Metal stocks Accumulation index Potamogeton crispus Lake Dongping 

分 类 号：X173[环境科学与工程—环境科学] X524