ABSTRACT

Many large rivers are experiencing a significant reduction in sediment flux owing to human activity. Sediment transport capacity directly affects the predictive accuracy of sediment concentration in morphodynamic modelling. A total of 1092 datasets with extremely low sediment concentrations in a quasi-equilibrium state were selected at five hydrometric stations of the Middle Yangtze River, and used to determine two parameters of a sediment transport capacity formula proposed by Zhang Ruijin. Firstly, the relationship between the effective sediment transport capacity and the comprehensive flow-sediment factor in the Middle Yangtze River was derived. Based on this relationship, Zhang’s sediment transport capacity formula was improved with its parameters being calculated according to varying flow and sediment conditions. Then the improved sediment transport capacity formula was successfully applied to other rivers with low sediment concentrations, also including a 347-km-long reach of the Middle Yangtze River.

摘要

由于人类活动，许多大河的沉积物通量正在显着减少。输沙能力直接影响形态动力学模型中泥沙浓度的预测精度。在长江中游5个水文站共选取1092个处于准平衡状态的极低含沙量数据集，用于确定张瑞金提出的输沙量公式的两个参数。首先推导了长江中游有效输沙能力与流沙综合因子之间的关系。在此基础上，改进了张氏输沙量公式，根据不同的流量和输沙条件计算其参数。