Phosphorus fractions, sorption characteristics, and its release in the sediments of Baiyangdian Lake, China.
Sediment phosphorus (P) fractions and sorption characteristics and P release from intact sediment cores of Baiyangdian Lake in North China in spring 2009 were investigated. Results of chemical fractionation showed that total P (TP) content in sediment ranged from 443 to 611 mg kg( -1). Of the P fractions including inorganic P (IP) and organic P (OP), IP was a dominant component of TP and present in the form of P bounded to calcium (Ca-P) while the bioavailable P content bounded to Al, Fe, and Mn oxides and hydroxides (Fe/Al-P) varied from 14 to 102 mg kg( -1). The batch experiments showed that the sediments had appreciable maximum P adsorption capacity from 141.86 to 377.37 mg kg( -1). However, the zero P equilibrium concentration (C⁰(eq))in most sampling sites was larger than the P concentration in water column. Accordingly, the sediments from those sampling sites would release P into the overlying water at the positive P flux rates as a P release source. Significant positive correlation between P flux rates and Fe/Al-P revealed that the sediment P release would mainly originate from the bioavailable P fraction. It is evident that the inherent phosphorus present in lake sediments would be a major threat to the water quality and ecosystem reservation in Baiyangdian lake.
State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China.
Liming
L
Dong
Zhifeng
Z
Yang
Xinhui
X
Liu
D000327:Adsorption; D002681:China; D004784:Environmental Monitoring; D005618:Fresh Water / Q000737:chemistry*; D019015:Geologic Sediments / Q000737:chemistry*; D010758:Phosphorus / Q000032:analysis* / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry
D014874:Water Pollutants, Chemical; D010758:Phosphorus