Inferences from catchment-scale tracer circulation experiments


Journal Article

In this paper the mechanisms determining the mobilization and transport of solutes driven by rainfall through runoff pathways at catchment scales are investigated through the analysis of tracer experiments. The hydro-chemical response of a small catchment in Northern Italy has been monitored in continuous during 4 weeks by properly measuring rainfall rates, streamflows and stream flux concentrations. The chemical response has been analyzed by employing two different tracers: nitrates from diffuse agricultural sources (NO3-) and lithium from a point injection (Li+). A modelling exercise simulating the observed hydro-chemical response of the test catchment has also been carried out. Inferences from the comparative analyses prove instructive, in particular concerning the scaling of mobilization processes and the age of runoff water. Indeed, the interactions between old and new water were found to be central to understand the mechanisms driving the transfer of solutes and pollutants from soil to stream water. The modeling exercises also evidenced the noteworthy potential of the formulation of transport by residence time distributions to describe large scale solute transport processes. © 2009 Elsevier B.V. All rights reserved.

Full Text

Duke Authors

Cited Authors

  • Botter, G; Milan, E; Bertuzzo, E; Zanardo, S; Marani, M; Rinaldo, A

Published Date

  • May 15, 2009

Published In

Volume / Issue

  • 369 / 3-4

Start / End Page

  • 368 - 380

International Standard Serial Number (ISSN)

  • 0022-1694

Digital Object Identifier (DOI)

  • 10.1016/j.jhydrol.2009.02.012

Citation Source

  • Scopus