三峡水库"蓄清排浑"的调度运行方式使得冬季高水位期间近岸消落带受淹.消落带氮、磷等营养物受淹后向水体中释放与积累对冬末初春的水华将可能具有重要贡献.构建高水位时期澎溪河高阳平湖总磷收支模型,定量分析高水位期间总磷的收支途径、累积量以及累积磷的主要来源.结果表明:蓄水期,由于蓄水水位升高和顶托而导致大量磷积累;稳定期,磷收支变幅较小,总体趋于平缓;水华期,前期积累的磷被大量消耗,形成水华.淹没消落带磷释放是冬季高水位时期高阳平湖总磷的主要来源,蓄水期所淹没大量消落带所释放的磷为冬季末水华暴发提供条件.研究结果为后续定量分析磷形态的转化和分配奠定重要基础.
The mode of operation of storing clear and releasing muddy in Three Gorges Reservoir makes drawdown areas submerged alongshore during the period of high water level in winter. After drawdown areas are submerged,the accumulation and release of nutrients such as nitrogen and phosphorus may have an important contribution to the algae bloom at the end of winter. This article establishes a model of the total phosphorus,which analyzes the balance of payments and the cumulant of total phosphorus,as well as the main source of cumulative phosphorus during the period of high water level in Lake Gaoyang of Pengxi River. In impounding stage,the increasing water level led to a great amount of phosphorus accumulation. In stable stage,the total tends to be mild. In algae bloom stage,the accumulation of phosphorus is consumed heavily in early time,forming algae bloom. The release of phosphorus in submerged drawdown area is the main source of total phosphorus throughout the period in Lake Gaoyang. It provides conditions for the outbreak of algae bloom at the end of winter. The results have set a solid foundation for the conversion and distribution of phosphorus forms.