Ecological Studies Analysis and Synthesis Edited by W.D. Billings, Durham (USA) F. Golley, Athens (USA) O.L. Lange, Wiirzburg (FRG) J.S. Olson, Oak Ridge (USA) K. Remmert, Marburg (FRG) Volume 37 Hans Jenny The Soil Resource Origin and Behavior With 191 Figures I Springer-Verlag New York Heidelberg Berlin Hans Jenny Professor Emeritus Department of Plant and Soil Biology College of Natural Resources University of California Berkeley, California 94720 USA Library of Congress Cataloging in Publication Data Jenny, Hans, 1899- The soil resource. (Ecological studies, v.37) Bibliography: p. Includes index. I. Soil formation. 2. Soil ecology. I. Title. II. Serie~. S592.2.J46 631.4 80-11785 All rights reserved. No part of this book may be translated or reproduced in any form without written permission from Springer-Verlag. The use of general descriptive names, trade names, trademarks, etc. in this publication, even if the former are not especially identified, is not to be taken as a sign that such names, as understood by the Trade Marh and Merchandise Marks Act, may accordingly be used freely by anyone. © 1980 by Springer-Verlag New York Inc. Softcover reprint of the hardcover 1st edition 1980 9 8 7 6 5 4 3 2 I ISBN-13: 978-1-4612-6114-8 e-ISBN-13: 978-1-4612-6112-4 001: 10.1007/978-1-4612-6112-4 This book is dedicated to my wife Jean Jenny in appreciation of her persistent, successful efforts-with important help from many supporters-to preserve for research and education the natural landscape areas: Apricum Hill laterite crust near lone, California Mt. Shasta mudflow research area Pygmy forest ecological staircase (Jug Handle Reserve) and others still in the slow process of acquisition. Foreword: Hans Jenny and Fertile Soil Hans Jenny has an unusual capacity for originating ideas, applying them and communicating them to others. In any field of knowledge, truly original ideas are rare, and particularly those which are pursued to the point of stimulating an entire generation of scholars in the field. Hans Jenny has done precisely that for soil science. Those who are or have been privileged to be his colleagues, students and friends are deeply grateful. (I) PAUL R. DAY The soil resource is supporting a growing world. Hans Jenny's fertile imagination has supported the science of origin of soils. Now it supports a broadening and deepening of the foundations of ecology. Vignettes from Jenny's life story tell something of how these twin contributions came to pass. They illustrate how ideas and traditions can crossbreed with one another for hybrid vigor in the history of science. I hope they show a bit deeper insight into creativity than we can usually learn from leading architects of science. Historians of science can follow details in an Oral History of Jenny's life (7). The Editors of Ecological Studies and Springer-Verlag feel especially privileged to make available not only the present book as a major historic contribution to pedology and ecology, but also the following personal sidelights about how that contribution was created over a full lifetime of observations, analysis, and synthesis. The second half of this book is a substantial extension of the natural philosophy that lit up the world in the classic Factors of Soil Formation in 1941 (5), a popular textbook, long out of print and pagewom by heavy use. Jenny's factor-function paradigm, or framework for organizing thought, is as lively as ever today. It seems likely to me to enjoy a still broader renaissance for the remainder of the twentieth century and for the twenty-first, as the world's people come to realize-and try harder to understand and reverse--our wasting of the rich and varied resources of soils and ecosystems now exploited ever more intensively. The first half of the present book reaches far back to the foundations of many sciences. It shows concisely, in as self-contained a manner as possible, how these contribute to understanding the many processes that maintain our soil resource as an operating system-part of the larger ecosystems of various sizes. The fundamental concept of balance or imbalance of forces, of energy budgets, of rates of mass income and loss, here emerge from physics and chemistry to give a view of changing soil (or changing ecosystems) in terms of quantitative rates. Where the change is not zero (the ideal balanced system, rarely found in Nature), the rate of viii Foreword change is simply described by the rate of income and rate of loss. Our home's energy budget, our firm's inventory, our nation's debt, and humanity's numbers all have accounts that change at rates that are equal to the inputs minus the outputs. Jenny's "system view" of the soil was carried into the fertile fields of Midwestern American prairies from the laboratories of Switzerland in the late 1920s. Jenny's rate equations provided the other paradigm or world view that, I recall, brought us to the threshold of systems ecology as it later evolved in the second half of the twentieth century. As if world renown in the specialties of pedology and soil chemistry were not enough for one lifetime, excerpts below remind us that Hans Jenny has also been a perceptive outdoor field ecologist since his early Alpine expeditions with Braun­ Blanquet in the mid 1920s. Jenny's ecosystem studies in the pygmy forest, a further classic example of a soil-plant system "run down" over hundreds of thousands of years since its origin, continue to occupy some of the vigorous retirement time near his farm in Mendocino County. But each specific, quantitative case study, and each research area conserved (with additional hard work) for further study by future generations, fits into Jenny's coherent world view. It is that view, and its legacies of discovery and of tangible landscape preserves, which we are privileged to share with their originator in this volume. In his eighties, Hans Jenny has also remained active in relating some of his favorite research areas to our global ecosystem problem of carbon and nitrogen cycling. Jenny's notes for his Oral History (7) and the personal knowledge I have enjoyed with Hans Jenny since my own semester pilgrimage to Berkeley in 1950, may therefore help many kinds of readers to find more of Jenny's own life story between the lines in the remainder of this book. Little Hans (born 1899) grew up mostly in Basel, with a student's sparkling view of the world from the extraordinarily powerful technical institute in Zurich, and later with a series of very productive positions in his adopted America. Typical of Hans's always fresh observations was a teen-age incident while on farming "duty" in the Swiss valleys in World Wa: I. The boy from town was awed by the distant view of the' 'snow mountain' '-but his host family had lived with it for years without even noticing. Hans still points out fresh views of a world we have lived in without fully seeing. He shares with us his special scientific perception, as well as his admiration for each view. The beauty lies not only in landscapes he describes here (reviewed from an artistic standpoint in his famous Vatican lecture on pedology and art) (6). The Platonic beauty of Jenny's ideas emerges from their elegant ways of connecting so many fragments of knowledge that might otherwise become lost in their various pigeonholes-if not forgotten altogether. Each of Jenny's life sojourns brought new insights, which then hybridized with one another in a kind of cross-fertilizing of ideas. This hybrid vigor of definitions and hypotheses was then subject to severe natural selection, a "survival of the fittest" theory, to make sense of the world. That selection involved the balance in a system of ideas: the fresh mutations of the intellectual world. Whence came this originality? the cross-breeding? the survival of two paradigms? Georg Wiegner, Jenny's mentor at Zurich (7), was the Professor of Agricultural Chemistry, a physical chemist who motivated and guided Jenny's early work on ion exchange. (That continuing interest is reflected later in the present book.) Jenny's famous syllabus on colloid chemistry (4) not only reflects this individual interest, but Foreword ix the power of the giants of physical science whom Hans could see and hear around Zurich. Yet Wiegner opened Hans's eyes to the fresh view of Hilgard from Berkeley and Dokuchaev from Russia, still unconventional for European agriculture of the 1920s. With more field experience than his mentor had time for, as in his vacation excursions collecting samples for analysis, Hans soon gained the precocious power to make connections that none of his predecessors was equipped for. The early "hybrid" book on soil acidification and successions (3) promptly gained worldwide attention in the Fuller/Conard English edition of Braun-Blanquet's Plant Sociology (2). When Tiixen in the 1950s praised the little book as a classic, I replied laughingly that it was a Jugendsiinde (an illegitimate product of youth). In one of the sections I drew a speculative curve relating humus to climate, relying on some of Hilgard's analyses. It was a premature embryo, but nevertheless the concept of a climofunction was clearly stated ..... I never dreamed that a decade later I would sit in his chair in Berkeley, California, and teach his course on soil formation. When I expressed a desire to study plant nutrition with Professor Hoagland in California I was politely told to forget it and select a place nearer the Atlantic Coast [by a visitor named A.