title: Metal release/accumulation during the decomposition of Potamogeton crispus in a shallow macrophytic lake.
abstract: 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 Fe- and Mn-oxides. It was estimated that 160 g/m(2) (dry weight) P. crispus was decomposed in 40 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 1m(2) area.
authors.affiliation: School of Environment and Planning, Liaocheng University, Liaocheng 252059, China. Electronic address: lcdhg@lcu.edu.cn.
authors.forename: Huanguang
authors.initials: H
authors.lastname: Deng
authors.affiliation: School of Environment and Planning, Liaocheng University, Liaocheng 252059, China.
authors.forename: Ju
authors.initials: J
authors.lastname: Zhang
authors.affiliation: School of Environment and Planning, Liaocheng University, Liaocheng 252059, China.
authors.forename: Shiyue
authors.initials: S
authors.lastname: Chen
authors.affiliation: School of Environment and Planning, Liaocheng University, Liaocheng 252059, China.
authors.forename: Liwei
authors.initials: L
authors.lastname: Yang
authors.affiliation: School of Geographical Sciences, East China Normal University, Shanghai 200241, China.
authors.forename: Dongqi
authors.initials: D
authors.lastname: Wang
authors.affiliation: Institute for Cultural Heritage, Shandong University, Jinan 250100, China.
authors.forename: Shiyong
authors.initials: S
authors.lastname: Yu
mesh_terms: D001673:Biodegradation, Environmental; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry; D060106:Lakes / Q000737:chemistry; D019216:Metals, Heavy / Q000032:analysis*; D031821:Potamogetonaceae / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis
chemical_list: D019216:Metals, Heavy; D014874:Water Pollutants, Chemical
keywords: Accumulation index; Lake Dongping; Litter decomposition; Metal release/accumulation; Metal stocks; Potamogeton crispus