1.Sichuan Agricultural University;2.Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences
Supported by the National Natural Science Foundation of China (No.41977004), Youth Innovation Promotion Association of the Chinese Academy of Sciences (CAS) (No.2019052), and the Outstanding Young Talent Project of Institute of Geographic Sciences and Natural Resources Research, CAS (No.2017RC203)
土壤有机磷（Po）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（Pi）相比，以往的研究对Po的重视不够，这主要是由于土壤中Po的提取、分析和鉴定方法难于Pi。近年来，随着液相31P核磁共振（31P NMR）波谱技术在土壤学领域的应用，为定量分析土壤Po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Po的转化特征奠定了基础。本文主要总结了土壤Po的种类和性质，介绍了液相31P NMR分析土壤Po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Po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Po转化速率、途径与环境阈值，阐明不同发育阶段土壤Po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Po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。
Soil organic phosphorus (Po) is an important phosphorus pool in soils. The forms, contents and bioavailability of Po change significantly with pedogenesis, which affects soil P supply, nutrient balance and ecosystem productivity. However, compared with inorganic phosphorus (Pi), previous studies paid less attention to Po, which was mainly attributed to the difficulty in the extraction, analysis and identification of different Po speciation. In recent years, the solution 31P nuclear magnetic resonance (31P NMR) spectroscopy was increasingly applied in pedology for characterizing Po compounds, providing a new way for quantitative analysis of Po forms and contents. This significantly improved our understanding of the transformation process of Po during long-term terrestrial ecosystem evolution. This paper systematically summarized the forms and properties of soil Po, and described the principle and procedures of solution 31P NMR spectroscopy for characterizing soil Po speciation. Then we reviewed the evolution trends and controls of different Po speciation during natural pedogenesis, and put forward several questions that need to be resolved in the future. Future research priorities include (i) determining the rates, pathways and thresholds of soil Po transformation during long-term soil evolution; (ii) elucidating the coupling relationship between Po and other nutrients such as C and N at different stages of soil evolution and the mechanisms of fixation and release of soil Po; and (iii) building a quantitative model of Po evolution in different types of soils. Providing solutions to the above questions can improve our understanding of the phosphorus biogeochemical cycle in Earth’s Critical Zone and provide a theoretical basis for nutrient management and regulation at different stages of soil evolution, and would promote sustainable utilization of soil resources.
LUO Yuanjun, HUANG Laiming, YUAN Dagang. Research Progress of the Evolution Trends and Controls of Soil Organic Phosphorus Speciation during Natural Pedogenesis Based on Solution 31P Nuclear Magnetic Resonance[J]. Acta Pedologica Sinica, DOI:10.11766/trxb202105060240,[In Press]