Evaluating stream power distribution along river longitudinal profiles using Log S – log A plots

Abstract

Study region

Eighteen main rivers in Taiwan.

Study focus

This study focused on the analysis of total stream power (TSP) and specific stream power (SSP) along river longitudinal profiles, which are critical indicators of river dynamics. A new two-parameter regression model is proposed, addressing inaccuracies in traditional models and providing a more-precise representation of river profiles. By incorporating concavity, drainage area distribution, discharge, and river width relationships, the model identifies the locations of the TSP and SSP peaks. The study employs log (river slope, S) – log (drainage area, A) plots to evaluate the spatial variability of these metrics under diverse geomorphological and hydrological conditions.

New hydrological insights for the region

The model was used to categorize 18 rivers in Taiwan into three groups based on river source elevation and drainage area–flow length exponents. Key findings indicate that lower source elevations correspond to increased upstream drainage-area distribution and greater concavity. This highlights the interplay between intrinsic watershed characteristics and external hydrological forces in shaping TSP and SSP distributions. These insights provide a basis for improved river management, sediment transport predictions, and conservation efforts.