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山坡形态和坡面糙率影响地表径流的输移能力。坡面形态法能量测沿坡多种变化的影响和预报送到田野末级沟道内的年平均侵蚀置和产沙量。复杂坡面经过概化后可用土壤流失通用方程(USLE)计算其片蚀和细沟侵蚀。输移能力或泥沙输移比(SDR),可用典型地面纵断计算。这一方法可预测小流域(<25.9km~2)内由于片蚀和细沟侵蚀而产生的沙量。中型流域(0.26~2590km~2)的输沙能力取决于山坡形态和沟系特征。计算沟道输移能力的方法随着所采用资料的可靠性和期望达到的精度的不同而不同。直接法需要有河道和水库的观测资料,运用现场测量和摄影测量制图技术来识别并计算拦沙坑或沉沙沟的作用。预估法所依据的是泥沙输移比和流域面积之间所建立的关系。这些方法适用于不同的中、小流域。
Hillside morphology and slope roughness affect the transport capacity of surface runoff. Slope morphological energy measures the effects of multiple changes along the slope and forecasts the annual mean erosion and sediment yield to the last stage of the field. After generalization of complex slopes, the generalized equation for soil erosion (USLE) can be used to calculate pitting erosion and rill erosion. Transport capacity or sediment transport ratio (SDR), can be calculated using typical ground longitudinal. This method can predict the amount of sediment due to erosion and rill erosion in small watersheds (<25.9km ~ 2). The capacity of sediment transport in medium-sized basins (0.26 ~ 2590km ~ 2) depends on the shape of hillsides and the characteristics of ditches. The method of calculating channel transport capacity varies with the reliability of the data used and the expected accuracy achieved. Direct methods require observations of rivers and reservoirs, using on-site measurements and photogrammetric mapping techniques to identify and calculate the role of silos or sand silt traps. The estimation method is based on the relationship established between sediment transport and drainage area. These methods apply to different medium and small watersheds.