A sediment graph model based on an instantaneous unit sediment graph

Abstract

A model was developed for predicting sediment graphs from agricultural watersheds. Storm sediment graphs are predicted by convolving source runoff with an instantaneous unit sediment graph (IUSG). The IUSG is the distribution of sediment from an instantaneous burst of rainfall producing one unit of runoff. The IUSG is the product of an instantaneous unit hydrograph and the sediment concentration distribution. Initial sediment concentration of the IUSG is assumed to vary linearly with source runoff volume. A sediment‐routing function, based on travel time and sediment particle size, is used to predict the sediment concentration distribution. Tests with 50 storms from five watersheds showed that the model is applicable to agricultural watersheds in the Texas blacklands. It should be useful in designing reservoirs or in waterquality‐modeling problems.

A Sediment Graph Model Based on SCS-CN Method

“…Here a watershed is represented by storage systems that include the catchment processes, without including the specific details of process interactions. Examples of few conceptual models are given by (RendonHerrero, 1978;Williams, 1978;Singh et al, 1982;Chen and Kuo, 1984;Kumar and Rastogi, 1987;and Lee and Singh, 2005). Rendon-Herrero, (1978) defined the unit sediment graph (USG) resulting due to one unit of mobilized sediment for a given duration uniformly distributed over a watershed.…”

Estimation of temporal variation of sediment yield using GIS / Estimation de la variation temporelle de l'exportation sédimentaire grâce à un SIG

“…Empirical methods, which include the universal soil loss equation (USLE) (Wischmeier & Smith, 1978), the modified universal soil loss equation (MUSLE) (Williams, 1978) and the revised universal soil loss equation (RUSLE) (Renard et al, 1991b), combine the soil erosion from all processes in the catchment into one equation which makes use of empirical coefficients to represent the rainfall characteristics, soil properties, ground surface conditions, etc. These methods are simple in application and hence frequently used in different parts of the world (Julien & Tanago, 1991).…”

Estimation of Sediment Yield Using Total Sediment Yield Formulas and RUSLE

“…Anderson (1949) proposed the annual average sediment yield as the function of annual maximum peak discharge per unit area, drainage area per length of main river and vegetation density using the sediment data 11.5 to 517.0 km 2 of drainage area. Williams (1978) proposed the momentary unit sediment hydrograph based on sediment rating curve of rainfall amount and water discharge per unit depth. Raghuwanshi et al (1994) simulated the hydrological curve of sediment load (bed load) by rainfall using the concept of momentary unit sediment hydrograph, which was compared with the actual measured value of suspended load.…”