Feng Weiying, Tao Yingru, Wang Tengke, Yang Fang, Zhao Meng, Li Yuxin, Miao Qingfeng, Li Tingting, Liao Haiqing
School of Materials Science and Engineering, Beihang University, Beijing 100191, China.
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
Toxics. 2024 Jul 20;12(7):523. doi: 10.3390/toxics12070523.
Phosphorus (P) is a crucial nutrient in lake ecosystems and organic phosphorus (Po) is a significant component. However, the distribution characteristics and migration behaviour of Po in ice-water-sediment systems under freezing and thawing conditions in cold and arid regions remain unclear. This study aims to investigate the forms of Po and its contribution to endogenous P pollution. We selected three lakes (Dai, Hu, and Wu Lake) and employed phosphorus nuclear magnetic resonance (P-NMR) techniques to analyse the following: (1) The total phosphorus (TP) content, which was the highest in the water from Dai Lake (0.16 mg/L), with substantial seasonal variation observed in Wu Lake, where P content was four times higher in summer than in winter because of farmland drainage. (2) Eutrophication analysis, which indicated that Dai Lake had significantly higher eutrophication levels than Wu Lake, with P being the controlling factor in Dai Lake and both N and P in Wu Lake. The proportion of Po in the TP content was 90%, 70%, and 55% for Wu, Dai, and Hu Lake, respectively, indicating that Po was the main component of eutrophic lakes. (3) P-NMR, which revealed that orthophosphate (Ortho-P) and monoester phosphate (Mon-P) were the main P components in the winter, with a higher P content in Dai Lake. Ortho-P has a higher content in ice, indicating that inorganic phosphorus (Pi) migration is the main factor in ice-water media. Mon-P showed multiple peaks in Dai Lake, indicating a complex composition of adenosine monophosphate and glucose-1-phosphate. (4) The ice-water phase change simulation experiments, which showed that phosphate was the least repelled in ice, while pyrophosphate (Pyro-P) and macromolecular P were more repelled. Adding sediment enhanced the migration of P but did not change the repulsion of macromolecular P, suggesting the molecular structure as the main influencing factor. These results provide important scientific evidence for the quantitative analysis of Po pollution in lake water environments, aiding in P load reduction and risk prevention and control.
磷（P）是湖泊生态系统中的一种关键营养物质，有机磷（Po）是其重要组成部分。然而，在寒冷干旱地区冻融条件下，Po在冰-水-沉积物系统中的分布特征和迁移行为仍不清楚。本研究旨在探究Po的形态及其对内源磷污染的贡献。我们选取了三个湖泊（戴湖、胡湖和吴湖），并采用磷核磁共振（P-NMR）技术进行分析：（1）总磷（TP）含量，戴湖水体中的TP含量最高（0.16 mg/L），吴湖的TP含量存在显著的季节性变化，由于农田排水，夏季的磷含量比冬季高四倍。（2）富营养化分析表明，戴湖的富营养化水平显著高于吴湖，在戴湖磷是控制因素，而在吴湖氮和磷都是控制因素。吴湖、戴湖和胡湖的Po在TP含量中的占比分别为90%、70%和55%，表明Po是富营养化湖泊的主要成分。（3）P-NMR分析显示，正磷酸盐（Ortho-P）和单酯磷酸盐（Mon-P）是冬季主要的磷成分，戴湖的磷含量更高。Ortho-P在冰中的含量较高，表明无机磷（Pi）迁移是冰水介质中的主要因素。Mon-P在戴湖显示出多个峰，表明腺苷一磷酸和葡萄糖-1-磷酸的组成复杂。（4）冰水相变模拟实验表明，磷酸盐在冰中受到的排斥最小，而焦磷酸盐（Pyro-P）和大分子磷受到的排斥更大。添加沉积物增强了磷的迁移，但没有改变大分子磷受到的排斥，表明分子结构是主要影响因素。这些结果为湖泊水环境中Po污染的定量分析提供了重要的科学依据，有助于减少磷负荷以及预防和控制风险。
