Review of Properties and Management of Soils in the Tropics

The second edition of Properties and Management of Soils in the Tropics is a remarkable book—not only because its world-famous author, Pedro Sánchez, is the only soil scientist ever to receive the World Food Prize, be awarded a MacArthur “genius” Fellowship, and be elected to the US National Academy of Sciences—not only because the book is upto-date, coming at a crucial time, and absolutely encyclopedic, covering a vast number of topics, from the microscale of the rhizosphere to the global scale of the water and carbon cycles, in more than 650 double-columned, heavily referenced pages—but it is remarkable as well because it uses a literary device that is extremely rare in modern scientific works but well-known to generations of writers, from Brontë to Fitzgerald to Lemony Snicket, in which an author steps away from the text and addresses the reader personally. While reading along in Sánchez’s book, a reader may suddenly hear from the author himself with a personal anecdote, punctuated by the use of personal photographs in the figures, or even get his personal take on the current consensus regarding some topic. This remarkable book is thus authoritative, encyclopedic, and conversational. The first section of the book contains two introductory chapters, one giving an overview of the natural environment of the tropics in a time of global change, followed by one about the people who live in the tropics and their quest for food security, both chapters featuring detailed discussions (as well as the author’s personal and sometimes acerbic comments). The second chapter might be characterized as posing the question, “Why should we care about the tropics?” whereas the first chapter conveys the fragile uniqueness of the tropical environment. The second chapter might well be read before the first one because it lends higher purpose to any search for knowledge about tropical agriculture and the soils that sustain it. The next section, weighing in at 240 pages, virtually a book-within-a-book, provides a comprehensive discussion of tropical soil properties. Five of its eight chapters, all of which require a solid prior understanding of basic soil science and plant ecology, cover physical properties related to soil structure and soil water, mineralogy, acidity, biology, and organic carbon, this focused subject matter being prefaced by three overview chapters on the classification and management of tropical soils. The third of these chapters introduces the latest version of the Functional Capability Classification System, developed by Sánchez and Stanley W. Buol, which augments the US Soil Taxonomy with A horizon designations for attributes that figure importantly in the ability of soil to support plant productivity. These latter attributes, in turn, are organized according to three “core” soil properties considered to determine the ability of soils to provide ecosystem services: texture, mineralogy, and organic matter (Palm et al., 2007), a viewpoint to which the present reviewer also subscribes. The factual material on soil properties in this section is thoroughly integrated with discussions of the role they play in tropical soil management. For example, the chapter on soil structure and erosion contains discussions of exemplary soil and water conservation practices as well as conservation (minimum-tillage) agriculture. G. Sposito, Mulford Hall, MC 3114, Univ. of California, Berkeley, CA 94720-3114. *Corresponding author (gsposito@berkeley.edu).