Assessing sediment connectivity in dendritic and parallel calanchi systems

The concept of sediment delivery ratio of each hillslope cell SDRi was used as a measure of sediment connectivity since low values of this ratio imply a lack of connectivity (structural and/or hydrological). For each calanco the cumulative frequency distribution of the travel time allowed both to test the applicability of the exponential relationship used in SEdiment Delivery Distributed (SEDD) model to calculate SDRi and to estimate the coefficient β appearing in this relationship. Finally, the median travel time and the sediment delivery ratio SDRM of each calanco basin were calculated to evaluate the structural connectivity at calanchi basin scale. The analysis demonstrated that both a dendritic system has median travel time values less than those of a parallel system and that SDRM values of a dendritic system are higher than those of a parallel one. In conclusion, sediment connectivity of a dendritic system is higher than that of a parallel one.