摘要
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.
基金
supported by the Beijing Municipal Science and Technology Plan Project (No. Z181100005518005)
the National Natural Science Foundation of China (Nos. 51579009, 51879012)
the Major Science and Technology Program for Water Pollution Control and Treatment (No. 2018ZX07110004)
