Phosphorus fractions, sorption characteristics, and its release in the sediments of Baiyangdian Lake, China

Abstract

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.

Spatial Distribution, Adsorption/Release Characteristics, and Environment Influence of Phosphorus on Sediment in Reservoir

“…For instance, the concentration of total phosphorus in sediments is between 152.18 mg/kg and 275.12 mg/kg in the Antalya Lake of Turkey, and the contamination risk is low [38]. The concentration of sediment phosphorus ranges from 443 mg/kg to 611 mg/kg in Baiyangdian Lake, which has become a potential factor of water eutrophication [16]. Similarly, sediment P concentration is between 390 mg/kg and 810 mg/kg in the Three Gorges reservoir [15].…”

“…Zhang et al studied the adsorption and release of sediment P in the Three Gorges Reservoir and showed that the maximum adsorption capacity varied from 137.79 to 1975.5 mg/kg [15]. Dong et al, researched the adsorption and release characteristics of P in sediments of Baiyangdian Lake, which showed that P was a risk factor for water quality and ecosystems [16]. Experiments and the mass balance equation have been widely used to study the release flux of P in sediments, which is the effective method for exploring the influences of sediments on water quality [17][18][19][20].…”

Temporal-spatial distribution, environmental significance and release risks of phosphorus in the sediments of a tropical mountain’s deep drinking water reservoir in southeastern China

“…The current research on the sediment P fractions is more focused on shallow lakes [5,7,15]. There have been few studies of the spatial and temporal distribution of the sediment P fractions in a subtropical mountain deep-water lake (or reservoir).…”

Vertical distribution and release characteristics of phosphorus forms in the sediments from the river inflow area of Dianchi Lake, China

“…In recent years, sequential extraction procedures have been widely used in studies on the morphology of sediment P because it allows the rapid and effective extraction of the various forms of sediment P. Sediment P is usually divided into different forms, including exchangeable P (Ex-P), P bounded to Al and Fe oxides (Fe/Al-P), P bounded to calcium (Ca-P), inorganic P (Inorg-P) and organic P (Org-P) [4][5][6][7]. Although the total P (TP) content in the sediments reflects the eutrophic state of the lake to some extent, it is unable to predict the potential release risk and ecological hazard of P. The speciation distribution of P in the sediments can provide more information and help to understand the P cycles and P release tendency in the lake, and is one of the important parameters to predict the endogenous P release [8][9][10].…”