土壤有机磷(P_(o))是土壤中重要的磷库,其形态、含量与生物有效性随成土过程而发生变化,进而影响土壤磷素供应、养分平衡及生态系统生产力。然而,与土壤无机磷(P_(i))相比,以往的研究对P_(o)的重视不够,这主要是由于土壤中P_(o)的提取...土壤有机磷(P_(o))是土壤中重要的磷库,其形态、含量与生物有效性随成土过程而发生变化,进而影响土壤磷素供应、养分平衡及生态系统生产力。然而,与土壤无机磷(P_(i))相比,以往的研究对P_(o)的重视不够,这主要是由于土壤中P_(o)的提取、分析和鉴定方法难于P_(i)。近年来,随着液相^(31)P核磁共振(^(31) P NMR)波谱技术在土壤学领域的应用,为定量分析土壤P_(o)组分及含量提供了新的技术手段,同时为更好地理解生态系统演化过程中不同形态P_(o)的转化特征奠定了基础。本文主要总结了土壤P_(o)的种类和性质,介绍了液相^(31)P NMR分析土壤P_(o)的原理和方法,在此基础上综述了自然成土过程中不同形态P_(o)的转化特征及其影响因素,并指出了需进一步研究的方向和关键科学问题:包括量化成土过程中不同形态P_(o)转化速率、途径与环境阈值,阐明不同发育阶段土壤P_(o)与C、N等养分之间的耦合关系及其固释机理,构建不同类型土壤P_(o)演化模型。回答上述问题有助于更好地理解地球关键带磷素生物地球化学循环,为不同发育阶段土壤养分管理与调控及土壤资源可持续利用提供理论依据。展开更多
为深入探究小麦胚芽中的脂质成分,该研究采用不同溶剂分别提取小麦胚芽中的磷脂和中性脂质,利用核磁共振技术(nuclear magnetic resonance,NMR)对小麦胚芽中的脂质成分进行分析,结果表明:^(31)P NMR在小麦胚芽中检测到6种磷脂和相对应的...为深入探究小麦胚芽中的脂质成分,该研究采用不同溶剂分别提取小麦胚芽中的磷脂和中性脂质,利用核磁共振技术(nuclear magnetic resonance,NMR)对小麦胚芽中的脂质成分进行分析,结果表明:^(31)P NMR在小麦胚芽中检测到6种磷脂和相对应的5种溶血性磷脂,以及非脂质含磷化合物甘油磷脂酰胆碱(GPC);磷脂中含量最高的是磷脂酰胆碱(PC),其摩尔浓度为0.42μmol/g,摩尔分数为28.50%,质量浓度为0.31 mg/g,质量分数为30.20%;^(1)H NMR测定小麦胚芽中的多种中性脂质组成及含量,包括甘油三酯(TG)、甘油二酯(DG)、甘油单酯(MG)和游离脂肪酸(FA),其中含量最高的甘油酯是TG,占比为77.25%,含量最低的是2-甘油单酯(2-MG),占比为0.03%;小麦胚芽的甘油三酯和磷脂中检测出亚油酸(L)、油酸(O)和亚麻酸(Ln)等6种不饱和脂肪酸,其中亚油酸的含量最高,在甘油三酯中占比56.26%,在磷脂中占比45.37%。溶血性磷脂和GPC是磷脂的水解产物,DG、MG和FA是甘油三酯的水解产物,这些物质可以反映样品中脂质的水解程度。研究结果表明,利用NMR不仅能够对小麦胚芽脂质的组分进行定性定量分析,而且可以监测小麦胚芽脂质水解程度的变化。NMR技术在小麦胚芽相关产品的脂质分析研究具有重要作用。展开更多
The migration and transformation of phosphorus components in wastewater treatment plants(WWTPs)play a crucial role in the convergence and circulation of phosphorus.However,the composition and variation of dissolved or...The migration and transformation of phosphorus components in wastewater treatment plants(WWTPs)play a crucial role in the convergence and circulation of phosphorus.However,the composition and variation of dissolved organic phosphorus(DOP)in WWTPs were unclear because of its complex nature,hindering its efficient detection.In this study,the DOP species and their transformation during the treatment process in WWTP were comprehensively analyzed.First,two enrichment methods were assessed for their effectiveness at facilitating wastewater analysis:lyophilization and aluminum salt precipitation.Aluminum salt precipitation was found to be better because its application allowed 31P nuclear magnetic resonance(31P NMR)spectroscopy to identify more species in the secondary effluent:orthophosphate(Ortho-P)(81.1%–89.3%of the dissolved total phosphorus),pyrophosphates(Pyro-P)(0%–2.3%),orthophosphate monoesters(Mono-P)(7.0%–10.77%),orthophosphate diesters(Di-P)(1.0%–2.96%),and phosphonate(Phos-P)(1.7%–5.16%).Furthermore,the variation and transformation mechanism of phosphorus,particularly those of DOP,during the entire sewage-treatment process were elucidated.Among the treatment steps,biological treatment combined tertiary treatment achieved better DOP removal efficiencies.Therein,biological treatment mainly removed Mono-P and Di-P with removal efficiencies of 33.3%and 41.7%compared with the effluent of the grit chamber.Di-P has higher bioavailability and is more easily converted and utilized by microorganisms than Mono-P.However,Phos-P,with low bioavailability,was hardly utilized by microorganisms,which showed only 18.4%removal efficiency in biological treatment.In tertiary treatment,coagulation process exhibited higher removal ability of Ortho-P(69.1%)and partial removal efficiencies of DOP,resulting in an increase in the DOP proportion in TP.In addition,Phos-P could not be effectively removed through the biological treatment and was only partially reduced via the adsorption process by large particles,zoogloea or multinuclear hydroxyl complexes.The results of this study can provide a theoretical basis for efficient phosphorus removal in WWTPs.展开更多
Climate warming and nitrogen (N) deposition change ecosystem processes, structure, and functioning whereas the phosphorus (P) composition and availability directly influence the ecosystem structure under condi- ti...Climate warming and nitrogen (N) deposition change ecosystem processes, structure, and functioning whereas the phosphorus (P) composition and availability directly influence the ecosystem structure under condi- tions of N deposition. In our study, four treatments were designed, including a control, diurnal warming (DW), N deposition (ND), and combined warming and N deposition (WN). The effects of DW, ND, and WN on P composition were studied by 3~p nuclear magnetic resonance (3~p NMR) spectroscopy in a temperate grassland region of China. The results showed that the N deposition decreased the soil pH and total N (TN) concentration but increased the soil OIsen-P concentration. The solution-state 31p NMR analysis showed that the DW, ND and WN treatments slightly decreased the proportion of orthophosphate and increased that of the monoesters. An absence of myo-inositol phosphate in the DW, ND and WN treatments was observed compared with the control. Furthermore, the DW, ND and WN treatments significantly decreased the recovery of soil P in the NaOH-EDTA solution by 17%-20%. The principal component analysis found that the soil pH was positively correlated with the P recovery in the NaOH-EDTA solution. Therefore, the decreased soil P recovery in the DW and ND treatments might be caused by an indirect influence on the soil pH. Additionally, the soil moisture content was the key factor limiting the available P. The positive correlation of total carbon (TC) and TN with the soil P composition indicated the influence of climate warming and N deposition on the biological processes in the soil P cycling.展开更多
液相31P核磁共振(phosphorus-31 nuclear magnetic resonance,31P-NMR)是近年来用于分析沉积物有机磷组成的新技术.本研究围绕31P-NMR分析沉积物样品的制备过程(包括样品前处理方法、提取时间、提取剂比例、样品浓缩等)进行探讨.结果表...液相31P核磁共振(phosphorus-31 nuclear magnetic resonance,31P-NMR)是近年来用于分析沉积物有机磷组成的新技术.本研究围绕31P-NMR分析沉积物样品的制备过程(包括样品前处理方法、提取时间、提取剂比例、样品浓缩等)进行探讨.结果表明,采用风干的沉积物样品进行提取,磷的提取效率明显提高.提取过程中,沉积物磷的释放主要在前8 h,为提高磷的提取效率,可将提取时间延长至12~16 h.提取比例[m(沉积物)∶V(提取剂)]1∶8与1∶20相比,在浓缩倍数相同的情况下,前者获得的31P-NMR信号峰多于后者,因此提取比例倾向于使用1∶8.提取液样品在28℃下旋转蒸发浓缩,并经低温离心后,磷无显著损失.展开更多
文摘土壤有机磷(P_(o))是土壤中重要的磷库,其形态、含量与生物有效性随成土过程而发生变化,进而影响土壤磷素供应、养分平衡及生态系统生产力。然而,与土壤无机磷(P_(i))相比,以往的研究对P_(o)的重视不够,这主要是由于土壤中P_(o)的提取、分析和鉴定方法难于P_(i)。近年来,随着液相^(31)P核磁共振(^(31) P NMR)波谱技术在土壤学领域的应用,为定量分析土壤P_(o)组分及含量提供了新的技术手段,同时为更好地理解生态系统演化过程中不同形态P_(o)的转化特征奠定了基础。本文主要总结了土壤P_(o)的种类和性质,介绍了液相^(31)P NMR分析土壤P_(o)的原理和方法,在此基础上综述了自然成土过程中不同形态P_(o)的转化特征及其影响因素,并指出了需进一步研究的方向和关键科学问题:包括量化成土过程中不同形态P_(o)转化速率、途径与环境阈值,阐明不同发育阶段土壤P_(o)与C、N等养分之间的耦合关系及其固释机理,构建不同类型土壤P_(o)演化模型。回答上述问题有助于更好地理解地球关键带磷素生物地球化学循环,为不同发育阶段土壤养分管理与调控及土壤资源可持续利用提供理论依据。
文摘农田生态系统中土壤磷形态转化,影响土壤磷对作物的有效供应。土壤磷分为无机磷和有机磷两大部分。化学连续提取法(chemical sequential fractionation,CSF)研究土壤磷形态分级,采用不同的化学提取剂,分级提取土壤中组成或分解能力接近的有机无机含磷化合物,是目前表征土壤磷素形态的重要方法。但该方法虽历经改进,仍难以确切反映土壤磷的实际组成,提取的不同磷形态间存在重叠,有机磷和无机磷组分分级存在一定的误差;不同分级磷组分对作物的有效性,需谨慎评估。核磁共振波谱技术(nuclear magnetic resonance,NMR)根据核磁共振波谱图上共振峰的位置、强度和精细结构来研究土壤中含磷化合物的分子结构。液相31PNMR可以同吋检测出土壤中多种磷组分,如正磷酸盐、磷酸单酯、磷酸二酯、膦酸脂、焦磷酸盐和多聚磷酸盐,识别土壤提取物磷形态,可将有机磷与无机磷分开。本文综述了应用31P-NMR技术研究土壤磷形态组分的一些进展,总结了样品制备过程、NMR测试参数及在土壤磷形态转化研究中的应用。二维31P-NMR技术发展为鉴定分析土壤中更多种类的含磷化合物提供了契机。
基金support of the Major Science and Technology Program for Water Pollution Control and Treatment(No.2017ZX07106)the China Postdoctoral Science Foundation(No.2022M713469)+1 种基金the China Construction Technology Consulting Co.,Ltd.Youth Fund(No.Z2022Q15)the North China Municipal Engineering Design&Research Institute Co.Ltd.(HJ-2021-53-HJY).
文摘The migration and transformation of phosphorus components in wastewater treatment plants(WWTPs)play a crucial role in the convergence and circulation of phosphorus.However,the composition and variation of dissolved organic phosphorus(DOP)in WWTPs were unclear because of its complex nature,hindering its efficient detection.In this study,the DOP species and their transformation during the treatment process in WWTP were comprehensively analyzed.First,two enrichment methods were assessed for their effectiveness at facilitating wastewater analysis:lyophilization and aluminum salt precipitation.Aluminum salt precipitation was found to be better because its application allowed 31P nuclear magnetic resonance(31P NMR)spectroscopy to identify more species in the secondary effluent:orthophosphate(Ortho-P)(81.1%–89.3%of the dissolved total phosphorus),pyrophosphates(Pyro-P)(0%–2.3%),orthophosphate monoesters(Mono-P)(7.0%–10.77%),orthophosphate diesters(Di-P)(1.0%–2.96%),and phosphonate(Phos-P)(1.7%–5.16%).Furthermore,the variation and transformation mechanism of phosphorus,particularly those of DOP,during the entire sewage-treatment process were elucidated.Among the treatment steps,biological treatment combined tertiary treatment achieved better DOP removal efficiencies.Therein,biological treatment mainly removed Mono-P and Di-P with removal efficiencies of 33.3%and 41.7%compared with the effluent of the grit chamber.Di-P has higher bioavailability and is more easily converted and utilized by microorganisms than Mono-P.However,Phos-P,with low bioavailability,was hardly utilized by microorganisms,which showed only 18.4%removal efficiency in biological treatment.In tertiary treatment,coagulation process exhibited higher removal ability of Ortho-P(69.1%)and partial removal efficiencies of DOP,resulting in an increase in the DOP proportion in TP.In addition,Phos-P could not be effectively removed through the biological treatment and was only partially reduced via the adsorption process by large particles,zoogloea or multinuclear hydroxyl complexes.The results of this study can provide a theoretical basis for efficient phosphorus removal in WWTPs.
基金National Natural Science Foundation of China(41171241)the National Basic Research Program of China(2011CB403204)
文摘Climate warming and nitrogen (N) deposition change ecosystem processes, structure, and functioning whereas the phosphorus (P) composition and availability directly influence the ecosystem structure under condi- tions of N deposition. In our study, four treatments were designed, including a control, diurnal warming (DW), N deposition (ND), and combined warming and N deposition (WN). The effects of DW, ND, and WN on P composition were studied by 3~p nuclear magnetic resonance (3~p NMR) spectroscopy in a temperate grassland region of China. The results showed that the N deposition decreased the soil pH and total N (TN) concentration but increased the soil OIsen-P concentration. The solution-state 31p NMR analysis showed that the DW, ND and WN treatments slightly decreased the proportion of orthophosphate and increased that of the monoesters. An absence of myo-inositol phosphate in the DW, ND and WN treatments was observed compared with the control. Furthermore, the DW, ND and WN treatments significantly decreased the recovery of soil P in the NaOH-EDTA solution by 17%-20%. The principal component analysis found that the soil pH was positively correlated with the P recovery in the NaOH-EDTA solution. Therefore, the decreased soil P recovery in the DW and ND treatments might be caused by an indirect influence on the soil pH. Additionally, the soil moisture content was the key factor limiting the available P. The positive correlation of total carbon (TC) and TN with the soil P composition indicated the influence of climate warming and N deposition on the biological processes in the soil P cycling.