sweeping the nation about converting biomass to alcohol and gasohol...We are promised construction of ingenious machines that will pick up all crop residues in the fields and leaf litter and humus in the forests. The carbon and nitrogen cycles of ecosystems will be curtailed and soil stability endangered. Because of a possible climatic warm-up, we do not wish to accelerate humus oxidation and the concomitant flux of carbon dioxide from soil into the atmosphere. I am arguing against indiscriminate conversion of biomass and organic wastes to fuels. The humus capital, which is substantial, deserves being maintained because good soils are a national asset." Bibliography Jenny, Hans (1929) Relation of temperature to the amount of nitrogen in soils. Soil Science 27: 169–188. Jenny, Hans (1936) Simple kinetic theory of ionic exchange. I. Ions of equal valency. Journal of Physical Chemistry 40: 501–507. Jenny, Hans (1941). Factors of soil formation—a system of quantitative pedology. McGraw-Hill. Jenny, Hans (1961) E.W. Hilgard and the Birth of Modern Soil Science. Pisa, Italy: Collana della Rivista Agrochimia. Jenny, Hans (1968) The image of soil in landscape art, old and new. Pontifical Academy of Sciences Scripta Varia 32: 947–979. Jenny, Hans (1980) The Soil Resource, Origin and Behaviour, Springer-Verlag, New York. Jenny, Hans (1989) Hans Jenny. Soil Scientist, Teacher, and Scholar. Regional Oral History Office, The Bancroft Library, University of California–Berkeley, CA. Jenny, Hans (1994) Factors of Soil Formation. A System of Quantitative Pedology. New York: Dover Press. (Reprint, with foreword by R. Amundson, of the 1941 McGraw-Hill publication). pdf file format. Jenny, Hans and K. Stuart (1984) My friend, the soil. Journal of Soil and Water Conservation 39: 158–161. Jenny, Hans, R. Overstreet, and A.D. Ayers (1939) Contact depletion of bare roots as revealed by radioactive indicators. Soil Science 48: 9–24. Jenny, Hans, T.R. Nielsen, N.T. Colemna, and D.E. Williams (1950) Concerning the measurement of pH, ion activities, and membrane potentials in colloidal systems. Science 112: 164–167. See also Clorpt History of Soil Science Pedogenesis SCORPAN Notes References University of California, Hans Jenny, in memoriam Amundsen, R., 2004, History of Soil Science: Hans Jenny, pdf format, in Encyclopedia of Soils in the Environment. Hillel, D., J.L.. Hatfield, D.S. Powlson, C. Rosenweig, K. M. Scow, M.J. Singer and D.L. Sparks. Editors. (2004) Four-Volume Set, Volume 1–4, External links Hans Jenny Memorial Lecture in Soil Science - The Genius of Soil 1899 births 1992 deaths American soil scientists