An Experimental Study on the Relationship between the Developing Process of the Drainage Geomorphology and the Sediment Yield

摘要

Based on the general model of the drainage geomorphology that is in the initial developing stage, the developing process of the drainage geomorphology and the dynamic character of sediment yield of the different developing stage of the drainage geomorphology were studied under the condition of the artificial simulated rainfall. The results showed that the developing process of the drainage geomorphology can be defined three stages-early stage, active stage and stable stage according to the dynamic character of sediment transport rate. During the early stage, the drainage geomorphology development takes on the obvious process that is from the inordinate phase to ordinal phase, and the variation of sediment transport rate and time of different rainfall intensity presents power function. During the active stage, the drainage geomorphology development becomes further acute. The difference of the variation of sediment transport rate and time of different rainfall intensity is distinct. The variation of sediment transport rate and time of 0.5 mm/min and 2.0mm/min presents power function separately, and that of 1.0 mm/min presents exponent function. During the stable stage, the drainage geomorphology development becomes slow, and the variation of sediment transport rate and time of different rainfall intensity presents quadratic polynomial function.