Abstract Accurate estimation of sediment concentration is essential to establish physically-based erosion models. The objectives of this study were to evaluate the effects of flow discharge (Q), slope gradient (S), flow velocity (V), shear stress (τ), stream power (ω) and unit stream power (U) on sediment concentration. Laboratory experiments were conducted using a 10 × 0.1 m rill flume under four flow discharges (2, 4, 8 and 16 L min−1), and five slope gradients (5°, 10°, 15°, 20° and 25°). The results showed that the measured sediment concentration varied from 87.08 to 620.80 kg m−3 with a mean value of 343.13 kg m−3. Sediment concentration increased as a power function with flow discharge and slope gradient, with R2 = 0.975 and NSE = 0.945. The sediment concentration was more sensitive to slope gradient than to flow discharge. The sediment concentration was well predicted by unit stream power (R2 = 0.937, NSE = 0.865), whereas less satisfactorily by flow velocity (R2 = 0.470, NSE = 0.539) and stream power (R2 = 0.773, NSE = 0.732). In addition, using the equations to simulate the measured sediment concentration of other studies, the result further indicated that slope gradient, flow discharge and unit stream power were good predictors of sediment concentration. In general, slope gradient, flow discharge and unit stream power seem to be the preferred predictors for estimating sediment concentration.

中文翻译：

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模拟细流的泥沙浓度

摘要 泥沙浓度的准确估计对于建立基于物理的侵蚀模型至关重要。本研究的目的是评估流量 (Q)、坡度 (S)、流速 (V)、剪切应力 (τ)、河流功率 (ω) 和单位河流功率 (U) 对泥沙浓度的影响. 实验室实验使用 10 × 0.1 m 细沟在四种流量排放（2、4、8 和 16 L min-1）和五种坡度（5°、10°、15°、20° 和 25°）下进行. 结果表明，测得的含沙浓度从 87.08 到 620.80 kg m-3 不等，平均值为 343.13 kg m-3。沉积物浓度随流量和坡度梯度的幂函数增加，R2 = 0.975 和 NSE = 0.945。泥沙浓度对坡度梯度比对流量更敏感。单位河流功率（R2 = 0.937，NSE = 0.865）很好地预测了沉积物浓度，而流速（R2 = 0.470，NSE = 0.539）和河流功率（R2 = 0.773，NSE = 0.732）则不太令人满意。此外，利用方程模拟其他研究实测含沙量，结果进一步表明坡度、流量和单位河流功率是较好的含沙量预测指标。一般来说，坡度、流量和单位河流功率似乎是估算泥沙浓度的首选预测因素。使用该方程模拟其他研究的实测含沙量，结果进一步表明坡度、流量和单位河流功率是良好的含沙量预测指标。一般来说，坡度、流量和单位河流功率似乎是估算泥沙浓度的首选预测因素。使用该方程模拟其他研究的实测含沙量，结果进一步表明坡度、流量和单位河流功率是良好的含沙量预测指标。一般来说，坡度、流量和单位河流功率似乎是估算泥沙浓度的首选预测因素。