湖泊水环境肌醇磷酸盐迁移转化规律及其富营养化效应研究

Inositol phosphates are one of the most important composition of organic phosphorus in lake environment, especially for sediments of lakes. However, the biogeochemical cycling of inositol phosphates such as distribution characteristics, sources, and process in water-sediment interface were still unidentified, contribution of inositol phosphates to bioavailable phosphorus and its relationship with algal blooming is needed for clarification. This project will be performed in three typical lakes in China, including Lake Dianchi, Lake Tai， Lake Hongfeng and Lake Sihailongwan etc. The pretreatment, such as extraction and purification, for samples in lakes would be explored. Based on these pretreatment methods, 31P-NMR, HPLC-MS/MS, and enzymatic hydrolysis et al would be comprehensively applied to qualitative analysis and quantitative analysis. Characteristics of structures and compositions of inositol phosphates in varied environmental media including sediments, water, suspended particles etc. Differences of inositol phosphates including structure and compositions in these media would be discussed. And then significant of characteristics of inositol phosphates in tracer of sources of inositol phosphates would be clarified. Thus, sources of inositol phosphates and their contribution to lakes would be further clarified. Based on laboratory simulation and simulation experiments in situ, transformation and degradation of inositol phosphates at water-sediment interface, and which effects in eutrophication of lakes would be in-depth discussion. In summary, our project will make a great contribution to the biogeochemical theory of organic phosphorus in lakes, which also provides theory for water quality evaluation and pollution control of lake eutrophication.

肌醇磷酸盐是湖泊水环境，尤其是沉积物中有机磷重要组分之一。然而，肌醇磷酸盐在湖泊水环境中迁移转化规律如分布特征、来源和水-沉积物界面过程的认识基本空白，其对水体生物可利用性磷的贡献及与蓝藻水华等过程关系亟需阐明。项目拟以我国不同类型典型湖泊(滇池、太湖、红枫湖和四海龙湾等)为研究对象，建立湖泊水环境样品肌醇磷酸盐提取等前处理方法，综合运用31P-NMR、高分辨率HPLC-ESI-MS/MS和酶水解等肌醇磷酸定性与定量分析新技术，揭示肌醇磷酸在湖泊水环境各介质(沉积物、水体及颗粒物等)中结构和组分分布特征，差异及来源示踪意义，阐明湖泊水环境肌醇磷酸盐来源并估算相对贡献份额。结合室内模拟和室外原位模拟，深入探讨肌醇磷酸盐水-沉积物界面迁移转化特征及其富营养化效应。成果有助于完善湖泊有机磷生物地球化学循环理论，为湖泊富营养化评价与污染控制提供理论依据。

磷是已知生命过程必须的组成和营养元素之一，但是磷在地表生态系统迁移强度不断增强，造成了一些水体富营养化及蓝藻水华频繁暴发，并可能对人类生存造成了较高的风险。肌醇磷酸盐是湖泊水环境，尤其是沉积物中有机磷重要组分之一。项目立项之初，肌醇磷酸盐在湖泊水环境中迁移转化过程如分布特征、来源和沉积物-水界面过程等仍十分缺乏。项目以肌醇磷酸盐为主线，围绕其提取优化、表征、迁移转化及其影响因素等几个关键科学问题开展了系统研究，并探讨了肌醇磷酸盐生物地球化学过程及其与蓝藻水华过程耦合关系。对比优选了湖泊水环境多介质（如植物、土壤和沉积物）肌醇磷酸盐提取方法及定性定量表征方法，建立了一套肌醇磷酸盐与有机质相互作用分析方法；解析了湖泊水环境肌醇磷酸盐主要来源、贡献份额与归趋；探讨了肌醇磷酸盐生物地球化学循环特征及其生态环境效应。以上研究成果，一方面为湖泊内源治理提供依据，例如构建了肌醇磷酸盐组成特征与营养状态关系方程，为基于沉积物磷水平判断湖库富营养化状态提供了新的途径和方法，并进行了一定推广应用；另一方面，也为进一步探讨肌醇磷酸盐生物地球化学循环及其与湖泊营养状态关系提供了科学依据，丰富了有机磷地球化学循环过程。