FOCUS About MACRO

About MACRO

General Information

MACRO is a physically-based one-dimensional numerical model of water flow and reactive solute transport in field soils (Jarvis, 1994).

MACRO Developer : Nicholas Jarvis, Dept. Soil Sciences, SLU
Affiliation : Swedish University of Agricultural Sciences (SLU)
MACRO web site : http://bgf.mv.slu.se/ShowPage.cfm?OrgenhetSida_ID=5658 contains a full technical description of the MACRO model

Version 4.3 of the MACRO model is used for the FOCUS scenarios.

Note: FOCUS materials related to MACRO cannot be downloaded from the SLU MACRO homepage.

Short Model Description

The model calculates coupled unsaturated-saturated water flow in cropped soil, including the location and extent of perched water tables, and can also deal with saturated flow to field drainage systems. The model accounts for macropore flow, with the soil porosity divided into two flow systems or domains (macropores and micropores) each characterized by a flow rate and solute concentration. Richards' equation and the convection-dispersion equation are used to model soil water flow and solute transport in the soil micropores, while a simplified capacitance type-approach is used to calculate fluxes in the macropores. Exchange between the flow domains is calculated using approximate, physically-based, expressions based on an effective aggregate half-width. Additional model assumptions include first-order kinetics for degradation in each of four `pools' of pesticide in the soil (micro- and macropores, solid/liquid phases), together with an instantaneous sorption equilibrium and a Freundlich sorption isotherm in each pore domain.

Role and Place in FOCUS scenarios calculation

The MACRO model is used for one of the FOCUS groundwater scenarios (Chateaudun) and six of the ten FOCUS surface water scenarios (for calculating drainage inputs).

A shell program in Visual Basic, linked to Microsoft Access databases containing all the required parameter inputs was written specially for the FOCUS applications. This program and supporting materials and documentation can be downloaded from this FOCUS site.

Current use outside FOCUS

In various applications as can be seen from the list of publications in the next section.

Excerpt of existing model documentation

Jarvis, N.J., Bergström, L. and Dik, P.E. 1991. Modelling water and solute movement in macroporous soil. II. Chloride leaching under non-steady flow. Journal of Soil Science 42, 71-81.
Jarvis, N.J., Bergström, L. & Stenström, J. 1991. A model to predict pesticide transport in macroporous field soils. In : Proceedings of the National Symposium on Preferential Flow, (eds. T.J. Gish and A. Shirmohammadi), Dec. 1991, Chicago, IL, ASAE St. Joseph, MI, 308-317.
Andreu, L., Moreno, F., Jarvis, N.J. & Vachaud, G. 1994. Application of the model MACRO to water movement and salt leaching in drained and irrigated marsh soils, Marismas, Spain. Agricultural Water Management, 25, 71-88.
Jarvis, N.J., Stähli, M., Bergström, L. & Johnsson, H. 1994. Simulation of dichlorprop and bentazon leaching in soils of contrasting texture using the MACRO model. Journal of Environmental Science & Health, A29(6), 1255-1277.
Saxena, R.K., Jarvis, N.J. & Bergström, L. 1994. Interpreting non-steady state tracer breakthrough experiments in sand and clay soils using a dual-porosity model. Journal of Hydrology, 162, 279-298.
Jarvis, N.J. 1995. Simulation of soil water dynamics and herbicide persistence in a silt loam soil using the MACRO model. Ecological Modelling, 81, 97-109.
Gottesbüren, B., Mittelstaedt, W., Führ, F. 1995. Comparison of different models to simulate the leaching behaviour of quimerac predictively. In : Proceedings of the BCPC Symposium `Pesticide movement to water' (eds. A. Walker, R. Allen, S.W. Bailey, A.M. Blair, C.D. Brown, P. Günther, C.R. Leake, P.H. Nicholls), Warwick, 155-160.
Jarvis, N.J., Larsson, M., Fogg, P., Carter, A.D. 1995. Validation of the dual-porosity model MACRO for assessing pesticide fate and mobility in soil. In : Proceedings of the BCPC Symposium `Pesticide movement to water' (eds. A. Walker, R. Allen, S.W. Bailey, A.M. Blair, C.D. Brown, P. Günther, C.R. Leake, P.H. Nicholls), Warwick, 161-170.
Saxena, R.K. & Jarvis, N.J. 1995. Measurements and modelling of tracer transport in a sandy soil. Water, Air & Soil Pollution, 79, 409-424.
Andreu, L., Jarvis, N.J., Moreno, F. & Vachaud, G. 1996. Simulating the impact of irrigation management on the water and salt balance in drained marsh soils (Marismas, Spain). Soil Use and Management, 12, 109-116.
Bergstrom, L. 1996. Model predictions and field measurements of chlorsulfuron leaching under non-steady-state flow conditions. Pesticide Science, 48, 37-45.
Jabro, J.D., Jemison, J..M., Fox, R.H. & Fritton, D.D. 1994. Predicting bromide leaching under field conditions using SLIM and MACRO. Soil Science, 157, 215-223.
Besien, T.J., Jarvis, N.J., Williams, R.J. 1997. Simulation of water movement and isoproturon behaviour in a heavy clay soil using the MACRO model. Hydrology and Earth System Sciences, 1, 835-844.
Bourgault de Coudray, P.L., Williamson, D.R. & Scott, W.D. 1997. Prediction of chloride leaching from a non-irrigated, de-watered saline soil using the MACRO model. Hydrology and Earth System Sciences, 1, 845-851.
Thorsen, M., Jørgensen, P., Felding, G., Jacobsen, O.H., Spliid, N. & Refsgaard, J. 1998. Evaluation of a stepwise procedure for comparative validation of pesticide leaching models. Journal of Environmental Quality, 27, 1183-1193.
Villholth, K.G. & Jensen, K.H. 1998. Flow and transport processes in a macroporous subsurface-drained glacial till soil. II. Model analysis. Journal of Hydrology, 207, 121-135.
Alaoui, A.M. 1998. Transferts d’eau et de substances (bromures, chlorures et bactériophages) dans des milieux non saturés à porosité bimodale. PhD thesis, Dept. Geography, University of Bern, 148 pp.
Brown C.D., Marshall, V., Deas, A., Carter, A.D., Arnold, D. & Jones, R.L. 1999. Investigation into the effect of tillage on solute movement to drains through a heavy clay soil. II. Interpretation using a radio-scanning technique, dye tracing and modelling. Soil Use and Management, 15, 94-100.
Larsson, M.H. & Jarvis, N.J. 1999. Evaluation of a dual-porosity model to predict field-scale solute transport in a macroporous clay soil. Journal of Hydrology, 215, 153-171.
Larsson, M.H., Jarvis, N.J., Torstensson, G. & Kasteel, R. 1999. Quantifying the impact of preferential flow on solute transport to tile drains in a sandy field soil. Journal of Hydrology, 215, 116-134.
Larsson, M.H. & Jarvis, N.J. 1999. A dual-porosity model to quantify macropore flow effects on nitrate leaching. Journal of Environmental Quality, 28, 1298-1307.
Brown, C.D., Beulke, S. & Dubus, I. 1999. Simulating pesticide transport via preferential flow: a current perspective. In: Proc. XI Symposium on Pesticide Chemistry, Human and Environmental exposure to xenobiotics (eds. A.A.M. del Re, Brown, C., Capri, E., Errera, G., Evans, S.P. & Trevisan, M.), September 1999, Cremona, Italy, 73-82.
Jene, B., Erzgraeber, B., Feyerabend, M., Fent, G. & Kubiak, R. 1999. Comparison of bromide and benazolin transport in the undisturbed field with simulations by the computer models PELMO and MACRO. In: Proc. XI Symposium on Pesticide Chemistry, Human and Environmental exposure to xenobiotics (eds. A.A.M. del Re, Brown, C., Capri, E., Errera, G., Evans, S.P. & Trevisan, M.), September 1999, Cremona, Italy, 131-142.
Granitza, E., Jene, B., & Feyerabend, M., 1999. Isoproturon: simulation of a field experiment on a drained loamy soil using the MACRO model. In: Proc. XI Symposium on Pesticide Chemistry, Human and Environmental exposure to xenobiotics (eds. A.A.M. del Re, Brown, C., Capri, E., Errera, G., Evans, S.P. & Trevisan, M.), September 1999, Cremona, Italy, 321-324.
Jarvis, N.J., Villholth, K.G. & Ulén, B. 1999. Modelling particle mobilization and leaching in macroporous soil. European Journal of Soil Science, 50, 621-632.
Armstrong, A., Aden, K., Amraoui, N., Diekkrüger, B., Jarvis, N., Mouvet, C., Nicholls, P. & Wittwer, C. 2000. Comparison of pesticide-leaching models: results using the Brimstone Farm data set. Agricultural Water Management, 44, 85-104.
Jarvis, N.J., Brown, C.D. & Granitza, E. 2000. Sources of error in model predictions of pesticide leaching: a case study using the MACRO model. Agricultural Water Management, 44, 247-262.
Gottesbüren, B., Aden, K., Bärlund, I., Brown, C., Dust, M., Görlitz, G., Jarvis, N., Rekolainen, S. & Schäfer, H. 2000 Comparison of pesticide leaching models: results using the Weiherbach data set. Agricultural Water Management, 44, 153-181.
Villholth, K.G., Jarvis, N.J., Jacobsen, O.H. & de Jonge, H. 2000. Field investigations and modeling of particle-facilitated pesticide transport in macroporous soil. Journal of Environmental Quality, 29, 1298-1309.
Beulke, S., Brown, C.D. & Jarvis, N.J. 2000. MACRO: A preferential flow model to simulate pesticide leaching and movement to drains. In: Proc. of the ARW workshop ‘Modeling of environmental chemical exposure and risk’, Sofia, Bulgaria (October 1999), NATO publication series, in press.