Quantifying streamflow properties using a calculus-based differential approach

This research quantifies streamflow temporal configuration and demonstrates the advantages of examining the hydrologic record on a day-to-day basis, heretofore unavailable with statistical-based index parameters. The streamflow chronological structure represents a previously untapped wealth of information that would benefit ecohydrology allowing alternate lines of investigation, re-evaluating past research in a new light and expanding analysis options for ecohydrologists. Innovative approaches are introduced to quantify this important but overlooked hydrologic property. To accomplish this, a non-index calculus-based differential approach has been developed using the lag(1) temporal autocorrelation signature of streamflow. The techniques for quantifying discharge (Q), day-to-day discharge change (dQ/dt), rate of day-to-day discharge change (d2Q/dt2) and sequential discharge summations are explained and presented using updated data visualization methods. A dam release river impact case study for the Colorado River at Lees Ferry, Arizona, demonstrates this novel way of analyzing and comparing discharge datasets. A set of highly customizable tools for this new approach can be used as a stand-alone analysis or to complement other existing techniques. The result is a better understanding of the hydrologic regime, permitting more focused research and more effective management planning.