title: [Influence of scum of algal bloom on the release of N and P from sediments of Lake Taihu].
abstract: Sediment cores were sampled in macrophyte dominated zone, phytoplankton dominated zone and river mouth in Lake Taihu and incubated with one half of them added algae in laboratory in August to reveal the influence of algal accumulation on the release of nitrogen and phosphorus in sediments. Concentrations of dissolved oxygen (DO), total nitrogen (TN), total phosphorus (TP), ammonium, phosphate and other parameters were determined during cultivation of the sediment cores in dark. There were differences in release of TN and TP in sediments and significant variations in changes of DO, ammonium, phosphate in overlying water after adding algae. When DO declined to nearly zero, the changes of release of TN, TP in sediments differed from different ecological types of Lake Taihu with minus numbers of -0.1, -3.01 mg x (m2 x d)(-1) in macrophyte dominated zone, larger numbers of 31.1, 0.75 mg x (m2 x d)(-1) in phytoplankton dominated zone and 9.5, 2.46 mg x (m2 x d)(-1) in river mouth. The concentrations of ammonium in overlying water increased 3.62, 5.10, 6.57 mg/L and phosphate increased 53, 219, 418 microg/L in macrophyte dominated zone, phytoplankton dominated zone, river mouth, respectively. The changes of nutrients have good correlations with the decrease of DO and duration. The release of nutrients from sediments caused by accumulation and decay of algae may be the way that algal bloom satisfied itself.
authors.affiliation: State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China. amyzmy1028@163.com
authors.forename: Meng-Yuan
authors.initials: MY
authors.lastname: Zhu
authors.forename: Guang-Wei
authors.initials: GW
authors.lastname: Zhu
authors.forename: Yong-Ping
authors.initials: YP
authors.lastname: Wang
mesh_terms: D002681:China; D004784:Environmental Monitoring / Q000379:methods; D005068:Eutrophication; D005618:Fresh Water / Q000032:analysis; D019015:Geologic Sediments / Q000032:analysis*; D009584:Nitrogen / Q000032:analysis*; D010758:Phosphorus / Q000032:analysis*; D010839:Phytoplankton / Q000254:growth & development; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D014874:Water Pollutants, Chemical; D010758:Phosphorus; D009584:Nitrogen