湖库富营养化敏感分级水动力概率参数研究

鉴于按多年平均流量估计滞留时间进行富营养化敏感程度分类较为粗糙,在月平均尺度上,考虑径流量的概率分布,提出了滞留率、缓流率、倒灌保证率等新的水动力概率参数反映水体动力特征,使水体富营养化敏感程度的识别及分级建立在考虑年内变化及多年变化的基础之上,使之在敏感分级上有更高的分辨率.并以三峡水库为实例,进行了不同支流的水体水动力概率参数的计算.结果显示,不同支流水体间的敏感水动力概率参数有明显差别,依据水动力条件等因素对水体富营养化控制实施差别化管理是必要的. 

Study of the Hydrodynamic Probability Parameters on Eutrophication Sensitivity Classification of Lake and Reservoirs

In traditional way, water bodies are classified according to the residence time, which is estimated based on the multi-year average flowthrough, and the eutrophication sensitivity degrees of lakes reservoirs are evaluated. In this research, in consideration of probability distribution of flow-through, some new hydrodynamic probability parameters, including retention ratio, sluggish flow ratio and back flowing guarantee ratio, are proposed to represent the hydrodynamic futures of water bodies at monthly scale. With these parameters, the identification and classification of eutrophication sensitivity degrees can be established on the basis of considering both seasonal and multi-year variations, and the sensitivity hierarchy has higher resolution. A case study is conducted in the Three Gorges Reservoir, and the hydrodynamic probability parameters in some tributaries are calculated. The results indicate that parameters in different tributaries have obvious differences, and it is necessary to implement distinctive management of eutrophication according to different hydrodynamic conditions.