Resistance Partitioning of Headwater Mountain Streams A Case Study in Southern Ecuador

Abstract

Resistance partitioning is a standard method to divide total resistance into linear additive components. Nevertheless, in mountain rivers the consideration of linearity is questionable. This article analyses the resistance partitioning on five reaches with typical mountain river morphologies (three cascades and two step-pools) in the Quinoas River in southern Ecuador through the calibration of two equations: The calibrated Keulegan and another nondimensional hydraulic geometry equation calibrated with resistance measured in a plain bed. Each studied reach was divided into three to five cross sections to take geometric and hydraulic data for six months for a wide range of flows magnitudes. The calibrated Keulegan equation provides the best results based on the values presented in the literature, the calibrated nondimensional hydraulic geometry equation produces different values probably due to the presence of vegetation in the banks of the plain-bed reach.