Written by CSU Professor Emeritus Gary Peterson.
Dr. Parviz N. Soltanpour, Professor Emeritus, 83, passed away on March, 31 2020. He was born March, 21 1937 in Tehran, Iran. Parviz earned his B.S. in Agricultural Sciences in 1961 from the American University of Beirut in Lebanon, where he met his wife a nursing student Nassrin Alavi. 
He also earned his M.S. degree in Soil Science from the same university under the direction of Dr. Dale Fuehring, who greatly encouraged him to continue his studies for a Ph.D. degree. He earned his Ph.D. degree in Soil Chemistry and Plant Nutrition in 1965 at the University of Nebraska – Lincoln under the direction of Dr. Leon Chesnin. Soon after he received his Ph.D., he began his 36 year career (1966-2002) as a professor at Colorado State University (CSU).
He was first appointed as Assistant Professor of Horticulture at CSU in 1966 and was located at the San Luis Research Center (SLRC) near Center, CO. While at the SLRC, his research focused on soil fertility problems for potatoes. He demonstrated that N, P, and Zn needs were diagnosable by soil tests. He was one of the first to show that the P-Zn interaction was in the plant root and not in the soil and that banding of N, P, and Zn fertilizers at planting time was more efficient than broadcast fertilization. Also at that time, it was a popular belief that if potatoes received adequate N fertilizer early blight control was not necessary. Parviz studied the problem in cooperation with plant pathologists, and found a positive interaction between N fertilization and fungicidal control of early blight in potato. Their work removed the misconception and led to a better understanding of the complex of the fertility-disease system in the potato crop.
Dr. Soltanpour became Assoc. Prof. of Horticulture in 1972 and remained at the SLRC until 1974. In 1974, he received a new appointment as an associate professor of Agronomy and was relocated to the CSU campus in Fort Collins, Colorado to become Director of the CSU Soil Testing Laboratory, a position he held for 10 years. He was promoted to the rank of professor of Agronomy in 1977. As Lab Director, he had both research and teaching responsibilities. Parviz taught courses in Soil-Plant Chemistry Analysis, Tropical Soil and Crop Management, Soil-Plant Nutrient Relationships, and Advanced Soil Chemistry. He was one of the pioneers in introducing students to the theory and practical application of inductively coupled plasma atomic emission spectrophotometry (ICP) in soil and plant analysis.
During his tenure at CSU, Parviz took an active role in international development via advising of numerous international students. From 1985 to 1988 he was a soil fertility specialist with the MIAC Consortium and was stationed in Settat Morocco.
Dr. Soltanpour was also an inventor and held a patent along with Drs. R. C. Malmgren and J. E. Cipra titled the Soil Amendment with Rubber Particles that was filed 29 December 1989 and became a Patent on 14 May 1991. Soil Amendment techniques are described using solid rubber particles to be mixed with soil to improve porosity and reduce compaction. The rubber particles were preferably derived from scrap tires. The soil amendment techniques are especially useful for reducing compaction of soil under turf in sports fields, golf courses, pathways and the like. This invention was also used to reduce athletic injuries to humans and horses and improve soil porosity. The inclusion of rubber particles in soil also improves the efficiency of water and fertilizer. This invention has been adopted and used worldwide and is found in many playgrounds, athletic fields, pathways and the like.
Dr. Soltanpour was honored as an ASA Fellow in 2002 for his many contributions to soil science and in particular for his contributions to soil testing methodology. He co-authored 125-plus research and extension publications, and many of these are highly cited (more than ten of his papers have 100-plus citations), and his most significant publication, “A New Soil Test for Simultaneous Extraction of Macro‐and Micro‐nutrients in Alkaline Soils” has 900-plus citations. He and his students developed the universal soil test (Ammonium bicarbonate-DTPA) that simultaneously extracts macro- and micronutrients. He pioneered the idea of using ICP to analyze the universal extractant. At present, many laboratories in the U.S. and the world use Dr. Soltanpour’s test separately or in conjunction with ICP. While using his new test for routine soil analysis, Parviz discovered that there were environmental applications for the universal extractant. While doing routine analysis of garden soils from old mining towns in CO, he discovered that some samples had elevated levels of Pb and Cd. They traced the source of the Pb and Cd to silver mine spoils and as a result, the USEPA placed these town sites on the Superfund list.
Parviz was an active member of the American Society of Agronomy (ASA) and the Soil Science Society of America (SSSA). In addition to his outstanding research and teaching record, he held various leadership positions such as: Chair of the “Council on Soil Testing and Plant Analysis”; co-led the publication of the book, “Reference Methods of Soil Testing”; and President of the “Iranian Society of Agriculture and Life Science Professionals in North America”.
He is survived by his wife of 60 years Nancy, their 4 children; Dr. David Soltanpour, Susan, Robert, Dr. Kristine Soltanpour, and grandson Marc Robert.
