Applicability of selected sediment transport equations to pinyon-juniper woodlands.

Abstract

Data from 3 pinyon-juniper watersheds, located on the Beaver Creek watersheds in central-northern Arizona, were used to test the applicability of several sediment discharge formulas. Measured sediment concentrations and flow discharges, together with other measured and derived data were used for the computations of the sediment discharge formulas. The predicted transport rates differed significantly from the measured values. The relative best predictions were given by the total load formulas. This was a reasonable result regarding that about 85% of the actual sediments were transported as suspended loads. It was concluded that the performance of the prediction formulas depend largely on the availability of the sediment in the streams. The best predictions were obtained for the watershed with the highest sediment discharges. Stream flow carrying capacity in the range of light-weight material shouldn't be predicted with bed load formulas based and calibrated within a different range of particle size distribution. A correction procedure was applied to adjust the predictions of the sediment formulas compared to the measured values.