Last changed: 04 June 2020

MACRO a model of water flow and solute transport in macroporous soil.

Examples of applications:

  • Simulations of water flow and pesticide leaching from tile drained agricultural fields.
  • Estimations of contaminant concentrations in groundwater.
  • Reactive and non-reactive solute transport in soil lysimeters.

MACRO is a one-dimensional, process oriented, dual-permeability model for water flow and reactive solute transport in soil. The soil pore space is divided into a micropore and a macropore domain characterized by different flow rates and solute concentrations. For the micropore domain water flow is governed by Richards’ equation and solute transport by the convection-dispersion equation.

For the macropore domain water flow is gravity driven and the solute transport assumed to be solely convective. The lateral exchange of water and solutes between pore domains is calculated using approximate, physically-based, first-order expressions. Additional model assumptions include first-order kinetics for degradation in each of four `pools' of pesticide in the soil (micro- and macropores, solid and liquid phases), together with instantaneous or kinetic sorption.

Download the model

MACRO 5.2 (zip file)

Command line version of MACRO5.2 (zip file)

Download documents

Technical description (pdf)

Users guide(pdf)

Changes from earlier versions (pdf)

Frequently asked questions (pdf)

Recent references (pdf)

Parameter definition file (v07)

Macroutils, an R package for batch reading, writing, plotting and converting MACRO binary files (R 3.2) To download please contact

Macroutils user guide (pdf) To download please contact

Webpage for macroutils development versions