Research Progress in Molecular Composition, Dynamic Evolution and Environmental Processes of Dissolved Organic Phosphorus in Lakes

Dissolved organic phosphorus (DOP) is an important component of the phosphorus pool in natural lakes, typically accounting for 20% to 60% of the total phosphorus. Through mineralization and degradation, DOP can be utilized by organisms and this is closely related to the biogeochemical processes of phosphorus in lakes, the evolution of eutrophication, and the functions of aquatic ecosystems. Due to the diversity of the chemical composition and the complexity of the molecular structure of DOP in lakes, there are obvious shortcomings in the application of current analytical techniques, which restricts a comprehensive understanding of the cycling and transformation of DOP in water bodies and its coupling mechanism with the ecological environment. In recent years, with the rapid development of high-resolution mass spectrometry (HRMS), a new perspective has been provided for clarifying the molecular structure, dynamic transformation, and environmental effects of DOP. In view of this, this paper briefly introduces the basic principles and analysis procedures of HRMS, reviews the latest research progress in characterizing the sources and composition characteristics of DOP in natural lake water, discusses the key environmental processes and main influencing factors of DOP in lake ecosystems, and finally looks forward to the possible important directions for future development. Studies have shown that although HRMS can reveal the molecular composition diversity of DOP (such as CHOP-compounds, CHONP-compounds, CHOSP-compounds, CHONPS-compounds, etc.), it faces challenges such as interference from complex environmental matrices and the lack of standardized data processing software, making it difficult to achieve high-throughput and precise analysis. In the future, it is urgent to strengthen comparative studies on the molecular composition and chemical structure of DOP in different types of lakes, deepen the understanding of the reactivity and intrinsic mechanisms of lake DOP, and scientifically assess and predict the biogeochemical behavior and ecological environment functions of DOP. This research is helpful to deepen the understanding of the cycling process and regulatory mechanism of DOP in lake ecosystems, clarify the mechanism of water eutrophication and the coupling process of nutrient migration and transformation, and provide important scientific and technological support for water environmental pollution prevention and control and management.