Characteristics and distribution of phosphorus in surface sediments of a shallow lake
- Source:
- Journal of environmental sciences (China) 2023 v.124 pp. 50-60
- ISSN:
- 1001-0742
- Subject:
- agricultural pollution, bioavailability, biogeochemical cycles, esters, lakes, nuclear magnetic resonance spectroscopy, organic matter, orthophosphates, pH, principal component analysis, risk, rivers, sediments, China
- Abstract:
- Phosphorus (P) in sediments plays an important role in shallow lake ecosystems and has a major effect on the lake environment. The mobility and bioavailability of P primarily depend on the contents of different P forms, which in turn depend on the sedimentary environment. Here, sediment samples from Baiyangdian (BYD) lake were collected and measured by the Standards, Measurements, and Testing procedure and Phosphorus-31 nuclear magnetic resonance spectroscopy (31P NMR) to characterize different P forms and their relationships with sediment physicochemical properties. The P content in the sediments varied in different areas and had characteristics indicative of exogenous river input. Inorganic P (334–916 mg/kg) was the dominant form of P. The 31P NMR results demonstrated that orthophosphate monoesters (16–110 mg/kg), which may be a source of P when redox conditions change, was the dominant form of organic P (20–305 mg/kg). The distribution of P forms in each region varied greatly because of the effects of anthropogenic activities, and the regions affected by exogenous river input had a higher content of P and a higher risk of P release. Principal component analysis indicated that P bound to Fe, Al, and Mn oxides and hydroxides (NaOH-P) and organic P were mainly derived from industrial and agricultural pollution, respectively. Redundancy analysis indicated that increases in pH lead to the release of NaOH-P. Organic matter plays an important role in the organic P biogeochemical cycle, as it acts as a sink and source of organic P.
- Agid:
- 7664518
- https://doi.org/10.1016/j.jes.2021.10.012