Dataset Information

Seasonal characteristics of phosphorus sorption by sediments from plain lakes with different trophic statuses.

ABSTRACT: Phosphorus (P) sorption in sediments plays a significant role in trophic status of a lake. This study investigated the characteristics of P sorption in sediments from three lakes with different trophic statuses (moderately eutrophic, lightly eutrophic and moderately trophic) through kinetic, batch equilibrium and thermodynamic experiments. Results show that pseudo-second-order kinetics best describe P sorption in sediments from the three lakes. Fitting by modified Langmuir and Freundlich isotherms indicates that the moderately trophic lake sediment has higher sorption capacity (maximum of 0.848 mg g-1 at 35°C) than the sediments of the other two lakes at different temperatures (5, 15, 25 and 35°C). Thermodynamic results indicate that the processes of P sorption of the three sediments are spontaneous, entropy-driven and endothermic reactions. The risk of P release in sediments was analysed according to the calculated results of isotherms combined with the change in P fraction. Sediments from the moderately eutrophic lake act as a source in summer. The lightly eutrophic and moderately trophic lakes act as sources in spring and winter, and a pool in summer and autumn, respectively. Furthermore, the amounts of reductant-soluble P, calcium-bound P and iron-bound P are significantly related to the sorption capacity of sediments from the three lakes (p < 0.05). The different sediments have different P release risk, and P fraction in sediment is one of the significant factors of P sorption.

SUBMITTER: Huang W

PROVIDER: S-EPMC6124047 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Seasonal characteristics of phosphorus sorption by sediments from plain lakes with different trophic statuses.

Huang Wei W Chen Xing X Wang Kun K Jiang Xia X

Royal Society open science 20180815 8

Phosphorus (P) sorption in sediments plays a significant role in trophic status of a lake. This study investigated the characteristics of P sorption in sediments from three lakes with different trophic statuses (moderately eutrophic, lightly eutrophic and moderately trophic) through kinetic, batch equilibrium and thermodynamic experiments. Results show that pseudo-second-order kinetics best describe P sorption in sediments from the three lakes. Fitting by modified Langmuir and Freundlich isother ...[more]

PMID: 30224992

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Dataset Information

Seasonal characteristics of phosphorus sorption by sediments from plain lakes with different trophic statuses.

Publications

Seasonal characteristics of phosphorus sorption by sediments from plain lakes with different trophic statuses.

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