Martinus Theodorus van Genuchten1945—

Van Genuchten is particularly associated with the soil hydraulic model introduced in his 1980 paper A Closed-form Equation for Predicting the Hydraulic Conductivity of Unsaturated Soils. The formulation, especially when combined with the pore-size distribution theory of Yechezkel Mualem, became widely known as the Mualem–van Genuchten model and is extensively used to describe soil-water retention and unsaturated hydraulic conductivity.

He has also contributed to analytical and numerical software for modeling water and contaminant transport, including RETC, CXTFIT, STANMOD and the HYDRUS family of programs. In 2023 he received the Wolf Prize in Agriculture for his research on water flow and contaminant transport in soils.

Early life and education

Van Genuchten was born on 13 February 1945 in Vught, in the southern Netherlands. He grew up on a small family farm and was the third of eleven children.

Although his formal name is Martinus Theodorus van Genuchten, he has generally been known as Rien van Genuchten. In a 2024 autobiographical article, he explained that he was called "Rini" as a child before the name gradually became "Rien".

He entered the Agricultural College at Wageningen, now Wageningen University & Research, in 1962. He received his bachelor's degree in 1968 and completed graduate studies in irrigation and drainage, receiving his master's degree in 1971.

During his studies at Wageningen he spent about a year in Madagascar, where he worked on rice irrigation and hydrological measurements. His early research also included drip irrigation and analytical descriptions of water distribution in soils.

Career

Early career in the United States

Near the completion of his doctorate, van Genuchten joined the Department of Civil Engineering at Princeton University, where he worked from 1975 to 1978. His research there included numerical solutions for water flow and contaminant transport in variably saturated porous media.

At Princeton he worked with researchers including George F. Pinder and William G. Gray. Among the problems he investigated was how to represent unsaturated soil hydraulic properties using continuous analytical functions rather than interpolated experimental data.

In 1978 van Genuchten moved to Riverside, California. He subsequently spent about three decades associated with the U.S. Salinity Laboratory of the Agricultural Research Service of the United States Department of Agriculture, while also having an academic association with the University of California, Riverside.

Research

Vadose-zone hydrology

A major focus of van Genuchten's research has been the vadose zone, the part of the subsurface between the land surface and the groundwater table in which soil and rock pores contain both air and water.

Understanding water and chemical movement through this region is important to agriculture, groundwater recharge, contaminant migration, irrigation, flood processes and water quality. Van Genuchten developed analytical and numerical methods for describing these processes in variably saturated soils and rocks.

His research has included equilibrium and nonequilibrium solute transport, preferential flow, contaminant sorption, soil-water retention, unsaturated hydraulic conductivity, parameter estimation, salinity, root-water uptake and transport through structured soils and fractured materials.

Van Genuchten model

Van Genuchten's most widely used theoretical contribution is the soil hydraulic formulation published in his 1980 paper A Closed-form Equation for Predicting the Hydraulic Conductivity of Unsaturated Soils.

Applications

Van Genuchten's theoretical and computational work has been applied to agricultural, hydrological and environmental problems involving irrigation, salinity, groundwater recharge and pollutant transport.

His research has addressed the movement of pesticides, nutrients, pharmaceuticals, pathogens, colloids and other contaminants through soils and groundwater systems. He has also worked on multicomponent geochemical transport and radionuclide migration.

During his later work at UFRJ, van Genuchten participated in studies involving naturally occurring radioactive materials, uranium-related wastes and environmental problems associated with radioactive materials.

One project examined the radioactive-waste repository constructed after the 1987 Goiânia caesium-137 accident. Van Genuchten and collaborators used HYDRUS-1D to investigate water flow and possible radionuclide transport from the repository.

Scientific publishing and professional service

Van Genuchten was the founding editor of the Vadose Zone Journal, serving as its founding editor from 2001 to 2005.

The journal was established as an interdisciplinary publication for research on the unsaturated near-surface environment, including water flow, contaminant transport, fractured media and related soil, geological and environmental processes.

Van Genuchten also served in editorial roles for other scientific journals, including Water Resources Research, Journal of Contaminant Hydrology, Advances in Water Resources and Soil Science.

He has participated in international scientific committees and has given lectures, workshops and short courses in numerous countries. He also taught courses on numerical modeling and HYDRUS applications with collaborators including Jiří Šimůnek.

Awards and honors

Van Genuchten has received awards from organizations in soil science, hydrology and porous-media research.

1996 – Soil Science Research Award, Soil Science Society of America.

1998 – Don and Betty Kirkham Soil Physics Award, Soil Science Society of America.

2003 – elected Fellow of the American Association for the Advancement of Science.

2004 – honorary doctorate from the University of Hannover, Germany.

2005 – Dionýz Štúr Medal of Honor for Outstanding Achievements in the Natural Sciences, Slovak Academy of Sciences.

2010 – John Dalton Medal of the European Geosciences Union, for contributions to the understanding of flow and transport in the unsaturated zone.

2012 – Honorary Membership Award of the International Society for Porous Media (InterPore).

2016 – Don and Betty Kirkham Gold Medal.

2018 – Groundwater Prize of the 8th Prince Sultan Bin Abdulaziz International Prize for Water.