Phillip Barak


Phillip Barak – Professor

Soil chemistry and plant nutrition

UW-Madison, Department of Soil Science
1525 Observatory Drive
Madison, WI 53706-1299, USA
Office: 167A Soil Science
Phone: 608.890.0689
Fax: 608.265.2595


Program Affiliations

  • Department of Soil Science


  • B.S. Agriculture, 1976, Faculty of Agriculture (Rehovot), Hebrew University of Jerusalem
  • M.S. Soil Science, 1982, Faculty of Agriculture (Rehovot), Hebrew University of Jerusalem
  • Ph.D. Soil Science, 1988, Faculty of Agriculture (Rehovot), Hebrew University of Jerusalem

Awards and Honors

  • 2006-07 Wisconsin Teaching Scholar
  • 1999 EduCause Medal

Teaching and Research Overview

I teach soil chemistry, mineralogy, and element cycling in the introductory soil science course for soils and allied majors. I also teach a soil fertility and fertilizers course for advanced undergraduate and graduate students from horticulture, agronomy, and soil science.

In recent years, the central focus of my research program has been the recovery of plant nutrients from wastewater in forms that can be sustainably returned to agriculture. This work has taken me from molecular templates for crystallization of ammonium magnesium phosphate, struvite, in the lab toward recovery of phosphate in the form of the calcium phosphate mineral, brushite, at commercial scales from wastewater treatment plants. More recently, I have taken an interest in nitrogen recovery from wastewater of various types – municipal treatment plants, manure lagoons and food processing – to recover ammonium nitrogen by electrodialysis for return to agriculture. For the past 18 years, I have curated the Virtual Museum of Minerals and Molecules, an online resource for the molecular visualization of molecules and minerals of interest to soil and environmental sciences.

Selected Publications

Later pubs can be found at: (midpage)

Melby, E.S., D.J. Soldat, and P. Barak. 201x. Preferential soil sorption of oxygen-18 labeled phosphate. Communications in Soil Science and Plant Analysis (submitted).

Melby, E.S., D.J. Soldat, and P. Barak. 2011. Synthesis and detection of oxygen-18 labeled phosphate. PLoS One 6(4): e18420; doi: 10.1371/journal.pone.0018420

Avila-Segura, M, P. Barak, J. Hedtcke and J.L. Posner. 2011. Nutrient and alkalinity removal by corn grain, stover and cob harvest in Upper Midwest USA. Biomass and Bioenergy 35:1190-1195; doi: 10.1016/j.biombioe.2010.12.010.

Barak, P. 2010. Phosphate recovery from acid phase anaerobic digesters. U.S. Patent Appl. No. 20100282674.

Soldat, D.J., P. Barak, and B.J. Lepore. 2009. Microscale colorimetric analysis using a desktop scanner and automated digital image analysis. J. Chem. Educ. 86:617-620 (plus 6 pp. supplemental online material and AnalyzeMicroplateStatistics ImageJ macro)

Lepore, B.J., and P. Barak. 2009. A colorimetric microwell method for determining bromide concentrations. Soil Sci Soc. Am. J. 73:1130-1136; doi:10.2136/sssaj2007.0226 .

Barak, P., M.E. Tabanpour, M. Avila-Segura, J.M. Meyer. 2007. Struvite Crystallization. US Patent No. 7,182,872; rights assigned to WARF.)

Barak, P., and E.A. Nater. 2005. The Virtual Museum of Minerals and Molecules: Molecular visualization in a virtual hands-on museum. J. Nat. Resour. Life Sci. Educ. 34:67-71. []

Avila-Segura, M., J.W. Lyne, J.M. Meyer, and P. Barak. 2004. Rapid spectrophotometric analysis of soil phosphorus with a microplate reader. Comm. Soil Sci. Pl. Anal. 35:547–557.

Grunwald, S., and P. Barak. 2003. 3D geographic reconstruction and visualization techniques applied to land resource management. Trans. GIS 7(2):231-241.

Grunwald, S., and P. Barak. 2002. The use of VRML for virtual soil landscape modeling. System Analysis Modelling Simulation (SAMS) 41:755-776.

Grunwald S., P. Barak, and D.J. Rooney. 2001. Web-based virtual models for the earth science community. ASAE International Meeting in Sacramento, CA, July 29-August 1, 2001; Paper No. 013029. (pdf)

Orvis, K.S., I.L. Goldman, and P. Barak. 2001. Excess sulfate supply and onion-induced human antiplatelet activity. J. Plant Nutr. Soil Sci. 164:457-462

Grunwald, S., and P. Barak. 2001. Virtual reality modeling in earth sciences. p. 216-221. In: C. Landauer and K.L. Bellman. (ed.) The Proceedings of the International Conference on Simulation and Multimedia in Engineering Education & Virtual Worlds and Simulation. Soc. Modeling and Simulation International, San Diego, CA. [ISBN:1-56555-224-5; Western MultiConference on Computer Simulation. Phoenix, AZ, 7-11 Jan 2001] (illustrations at

Sherman, L.A., and P. Barak. 2000. The solubility and dissolution kinetics of dolomite [CaMg(CO3)2] in Ca-Mg-HCO3/CO3 solutions at 25°C and 0.1 MPa carbon dioxide. Soil Sci. Soc. Am. J. 64:1959-1968.

Grunwald, S., P. Barak, K. McSweeney, and B. Lowery. 2000. Soil landscape models at different scales portrayed in Virtual Reality Modeling Language (VRML). Soil Sci. 165:598-615. (illustrations at

Mafongoya, P.L., P. Barak, J.D. Reed. 2000. Carbon, nitrogen and phosphorus mineralization of tree leaves and manure. Biol. Fert. Soils 30:298-305.

Starr, G.C., P. Barak, B. Lowery, and M. Avila-Segura. 2000. Soil particle concentrations and size analysis using a dielectric method. Soil Sci. Soc. Am. J. 64:858-866.