Phosphorus Bioavailability and Release Potential Risk of the Sediments in the Coastal Wetland: A Case Study of Rongcheng Swan Lake, Shandong, China

摘要: Rongcheng Swan Lake, a natural coastal wetland, is connected to Bay of Yellow Sea, China. In this lagoon, water quality has deteriorated gradually in recent 30 years and filamentous Chaetomorpha linum have bloomed during the past five years. present study, concentration, fractions, bioavailability phosphorus (P) surface sediments were investigated throughout lake. order evaluate P retention ability six sediment samples from different lake regions collected study adsortion kinetics, capacity relation properties. total concentrations varied 79 616 mg/kg, which significantly higher northwest region than those southeast region. Sediment grain size external inputs main factors affecting distribution. Inorganic concentration was obviously that organic P, Ca-P important form sediments. Fe/Al-P showed large spatial variation, with relatively high occurring at northeastern corner western tip strongly affected by discharge wastewater. The adsorption isotherms well fitted Linear equation low conditions Langmuir initial concentrations, respectively. northern central had capacity, while southern degree saturation high. Ammonium oxalate extractable Al, matter, fine particle influencing adsorption. algae available (AAP) largest bioavailable followed Olsen-P; moreover, AAP Olsen-P significant correlations Fe/Al-P. As whole, TP Lake low, most buffering for overlying water; where macroalgal blooms frequently breakout, potential releasing into column.