In Memoriam
Donald Rodney Nielsen
Professor of Land, Air, and Water Resources, Emeritus
UC Davis
1931-2020
There are hardly words that may describe the professional dedication and achievements of Don. Throughout his career at the University of California in Davis and beyond, he influenced countless people who had an opportunity to spend time with him: colleagues, students, career staff and others. Many of us at UC Davis, and so many others nation-wide and across countries and continents abroad, have benefited from his interactions. All of those who have known him will remember his unique and outspoken personality, his well-intended candidness even if it was not always appreciated, his uncanny dedication to student education and professional service, and his genuine friendlessness throughout.
Donald Rodney Nielsen was born on October 10, 1931, in Phoenix, Arizona. He gained an early appreciation for soils and agriculture through his father's farming of vegetables. Don received a BS degree in Agricultural Chemistry and Soils in 1953 and a MS degree in Soil Microbiology in 1954, both from the University of Arizona. In 1958 he received his PhD in Soil Physics from Iowa State University under the supervision of Don Kirkham, and soon after he took a faculty position at UC Davis. He is survived by his wife Joanne, their five children, ten grandchildren and three great-grandchildren. Don was a giant within the field of Soil Physics and also beyond. He strongly argued for the integration of Soil Science with related environmental fields such as Agronomy, Hydrology and others.
Don Nielsen spent his entire career at UC Davis, where he contributed enormously through his teaching, research, and service. He shepherded the UC approval of MS and PhD degrees in Earth Sciences and Resources, as well as in Hydrologic Science. He was internationally renowned for his innovative achievements in the areas of chemical transport in soils, spatial variability of soils, nitrogen pollution from agricultural operations, hydrological properties of soils, and soil management due to microbial transformations. He was instrumental in designing alternative agronomic experiments using ‘non-aggie’ statistics to derive management decisions that are meaningful to farmers even today. He authored more than 300 publications and was an invited speaker at numerous national and international conferences. Very significantly, early in the 1960s was his seminal work with his friend and UC Davis professor Jim Biggar on formalizing the theory of miscible displacement in unsaturated soils, which did lead to some 100 joint publications. Continued collaboration with Jim in the 1970s involved their pioneering work on the characterization of field soil variability and implications for water movement and solute transport. Even with an extensive research program on these and related topics, Don carried out a full teaching load in the classroom, while serving simultaneously at several levels of administration within the College and the UC Davis Academic Senate. He further served as statewide Director of the Kearney Foundation of Soil Science and Director of the Food Protection and Toxicology Center. He also became Chair of two of the largest campus departments (Land, Air and Water Resources, and Agronomy & Range Science) and was Executive Associate Dean of the College of Agricultural and Environmental Sciences.
Don has been the advisor for many outstanding graduate students and has been the host to more than 90 international scientists from nearly 40 different countries. Through his teaching, research, and administrative efforts, as well as his service on countless national and international organizations, he has had a tremendous impact not only in the Soil and Hydrological Sciences, but also on Agricultural and Environmental Sciences in general. He was President of the Soil Science Society of America (SSSA), the American Agronomy Society (ASA), and of the Hydrology Section of the American Geophysical Union (AGU). He also served on the National Research Council’s (NRC) Board on Agriculture and chaired the U.S. National Committee of Soil Science, thereby representing the National Academy of Science (NAS) and U.S. soil scientists to the International Union of Soil Science (IUSS). Don held many contributing positions at the IUSS, including being President of the Soil Physics Commission, member of its Budget and Finance Committee, and chair of several of its symposia. Many other roles can be cited, such as his work for other national and international agencies. For example, he served on panels of the NRC and the Food and Agriculture Board of the NAS. He further served on numerous journal editorial boards and review panels of universities and research organizations, as well as consulted for national and international government agencies. Particularly noteworthy was his service on the editorial board of Water Resources Research and becoming its editor-in-chief in 1985.
Because of his unique accomplishments in research, student education and professional service, Don Nielsen was honored with numerous awards. He became a Fellow of ASA, SSSA and AGU. He received the M. King Hubbert Award of the National Ground Water Association, and was made a Honorary member of IUSS and the European Geophysical Society. Moreover, he received the rather prestigious Horton Medal of AGU’s Hydrology section in 2001 “for his fundamental and pioneering work in hydrology, combined with his uncanny love for the profession”. In 2008 he was awarded the Don and Betty Kirkham International Soil Physics Medal, which is awarded once every 8 years.
Don has been an unselfish servant to the soil, hydrologic and environmental communities worldwide. Throughout his career, he guided, challenged, moved, supported, and inspired people and organizations alike. His inspiration to students and colleagues was largely founded by his conviction that there is a universal need to protect and maintain soils globally, and to develop science and technologies that enable management of the globe’s natural resources without soil exhaustion. His ultimate wish was for this to be accomplished by upcoming generations of scientists, but avoiding any regional and global conflicts in the process.
Jan W Hopmans
Carlos E Puente
Donald Rodney Nielsen was born on October 10, 1931, in Phoenix, Arizona. He gained an early appreciation for soils and agriculture through his father's farming of vegetables. Don received a BS degree in Agricultural Chemistry and Soils in 1953 and a MS degree in Soil Microbiology in 1954, both from the University of Arizona. In 1958 he received his PhD in Soil Physics from Iowa State University under the supervision of Don Kirkham, and soon after he took a faculty position at UC Davis. He is survived by his wife Joanne, their five children, ten grandchildren and three great-grandchildren. Don was a giant within the field of Soil Physics and also beyond. He strongly argued for the integration of Soil Science with related environmental fields such as Agronomy, Hydrology and others.
Don Nielsen spent his entire career at UC Davis, where he contributed enormously through his teaching, research, and service. He shepherded the UC approval of MS and PhD degrees in Earth Sciences and Resources, as well as in Hydrologic Science. He was internationally renowned for his innovative achievements in the areas of chemical transport in soils, spatial variability of soils, nitrogen pollution from agricultural operations, hydrological properties of soils, and soil management due to microbial transformations. He was instrumental in designing alternative agronomic experiments using ‘non-aggie’ statistics to derive management decisions that are meaningful to farmers even today. He authored more than 300 publications and was an invited speaker at numerous national and international conferences. Very significantly, early in the 1960s was his seminal work with his friend and UC Davis professor Jim Biggar on formalizing the theory of miscible displacement in unsaturated soils, which did lead to some 100 joint publications. Continued collaboration with Jim in the 1970s involved their pioneering work on the characterization of field soil variability and implications for water movement and solute transport. Even with an extensive research program on these and related topics, Don carried out a full teaching load in the classroom, while serving simultaneously at several levels of administration within the College and the UC Davis Academic Senate. He further served as statewide Director of the Kearney Foundation of Soil Science and Director of the Food Protection and Toxicology Center. He also became Chair of two of the largest campus departments (Land, Air and Water Resources, and Agronomy & Range Science) and was Executive Associate Dean of the College of Agricultural and Environmental Sciences.
Don has been the advisor for many outstanding graduate students and has been the host to more than 90 international scientists from nearly 40 different countries. Through his teaching, research, and administrative efforts, as well as his service on countless national and international organizations, he has had a tremendous impact not only in the Soil and Hydrological Sciences, but also on Agricultural and Environmental Sciences in general. He was President of the Soil Science Society of America (SSSA), the American Agronomy Society (ASA), and of the Hydrology Section of the American Geophysical Union (AGU). He also served on the National Research Council’s (NRC) Board on Agriculture and chaired the U.S. National Committee of Soil Science, thereby representing the National Academy of Science (NAS) and U.S. soil scientists to the International Union of Soil Science (IUSS). Don held many contributing positions at the IUSS, including being President of the Soil Physics Commission, member of its Budget and Finance Committee, and chair of several of its symposia. Many other roles can be cited, such as his work for other national and international agencies. For example, he served on panels of the NRC and the Food and Agriculture Board of the NAS. He further served on numerous journal editorial boards and review panels of universities and research organizations, as well as consulted for national and international government agencies. Particularly noteworthy was his service on the editorial board of Water Resources Research and becoming its editor-in-chief in 1985.
Because of his unique accomplishments in research, student education and professional service, Don Nielsen was honored with numerous awards. He became a Fellow of ASA, SSSA and AGU. He received the M. King Hubbert Award of the National Ground Water Association, and was made a Honorary member of IUSS and the European Geophysical Society. Moreover, he received the rather prestigious Horton Medal of AGU’s Hydrology section in 2001 “for his fundamental and pioneering work in hydrology, combined with his uncanny love for the profession”. In 2008 he was awarded the Don and Betty Kirkham International Soil Physics Medal, which is awarded once every 8 years.
Don has been an unselfish servant to the soil, hydrologic and environmental communities worldwide. Throughout his career, he guided, challenged, moved, supported, and inspired people and organizations alike. His inspiration to students and colleagues was largely founded by his conviction that there is a universal need to protect and maintain soils globally, and to develop science and technologies that enable management of the globe’s natural resources without soil exhaustion. His ultimate wish was for this to be accomplished by upcoming generations of scientists, but avoiding any regional and global conflicts in the process.
Jan W Hopmans
Carlos E Puente
