State Key Laboratory on Environmental Aquatic Chemistry, Research Center for Eco-Environmental Science, Chinese Academy of Science, P.O. Box 2871, Beijing, 100085, China.
University of Chinese Academy of Science, Beijing, 100049, China.
Environ Sci Pollut Res Int. 2017 Nov;24(32):25469-25474. doi: 10.1007/s11356-017-0211-z. Epub 2017 Sep 30.
Solution P nuclear magnetic resonance spectroscopy (P-NMR) is a useful method for analyzing organic phosphorus (P). Unfortunately, the extraction conditions, which are highly alkaline and require long extraction times, make this analysis less effective. In this research, according to the lability of orthophosphate monoesters (mono-P) and orthophosphate diesters (diesters-P), we verified the hypothesized overestimation of mono-P in lake sediment using solution P-NMR. We set three scenes to redistribute the mono-P and diesters-P. Six components, including eight mono-P species, were detected in the NaOH-EDTA extracts of sediment samples using P-NMR. The results showed that mono-P (212.7 mg kg) was the dominant P in the surface sediment. In the three scenes, mono-P decreased from 212.7 to 112.0 mg kg, and diesters-P increased from 31.9 to 132.7 mg kg. The ratio of mono-P to diesters-P increased from 6.7 to 0.8. Therefore, we deduced that the concentration of mono-P was overestimated, while that of diesters-P was underestimated, in most research because of the high pH and long extraction process. Diesters-P might be an important labile P source during the P "exhausted" period.
溶液磷核磁共振波谱（P-NMR）是分析有机磷（P）的一种有效方法。但由于提取条件呈强碱性且需要较长的提取时间，这使得该分析的效果较差。本研究根据正磷酸盐单酯（mono-P）和正磷酸盐二酯（diesters-P）的不稳定性，利用溶液 P-NMR 验证了湖泊沉积物中 mono-P 被高估的假设。我们设定了三种场景来重新分配 mono-P 和 diesters-P。使用 P-NMR 从沉积物样品的 NaOH-EDTA 提取物中检测到了六种成分，包括八种 mono-P 物种。结果表明，mono-P（212.7 mg kg）是表层沉积物中的主要 P。在三种场景中，mono-P 从 212.7 降至 112.0 mg kg，而 diesters-P 从 31.9 增加至 132.7 mg kg。mono-P 与 diesters-P 的比例从 6.7 增加至 0.8。因此，我们推断，由于高 pH 值和较长的提取过程，大多数研究中 mono-P 的浓度被高估，而 diesters-P 的浓度被低估。在 P“耗尽”期间，diesters-P 可能是一种重要的不稳定磷源。
