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Soil Organic Matter Dynamics and Sustainability of Tropical Agriculture
Book Reviews/ Geoderma63 (1994)309-322
313
France. Most references are in French but English ones have been added at the end of the list to complete the original references. This book will be useful for people whose main subject is not pedology; it raises the problems they may be faced with. This is the reason why it is written as a guide, easy to consult, describing briefly the more usual analyses proposed in catalogues of soil analysis laboratories to characterize soils samples. Although numerous English-speaking readers may not be accustomed to the methods of analyses described here, they will nevertheless be interested in this book because its main purpose is to describe and to discuss a general approach to soil properties by analytical investigation. M. HARDY
SSDIOO16-7061(93)EOlI8-F
Orleans, France
Soil Organic Matter Dynamics and Sustainability of Tropical Agriculture. Edited by K.
Mulongoy and R. Merck. Wiley, Chichester, 1993, 392 pp. Hardcover. ISBN 0-47193915-3. This book contains a series of papers presented at the proceedings of an international symposium held in Leuven, Belgium in November, 1991. The symposium summarized five years of collaborative research between the International Institute of Tropical Agriculture (IITA) and the Laboratory of Soil Fertility and Biology of the Katholieke Universiteit Leuven (K.U. Leuven), Belgium. Research focused on the biological aspects of soil organic matter dynamics and soil fertility under various cropping systems used in the tropics. The book has four major subdivisions which roughly correspond to the symposium presentations. Papers are summarized individually. The introductory paper provides a nice summary of the definitions and measurements of sustainability. It also points out the significance of soil organic matter in the assessment of sustainability and discusses factors that need to be considered if organic matter sustainability is to be related to system sustainability. The five papers in part 1, "Characterization and Quantification of Soil Organic Matter", provide comparisons of the methods used for sampling and characterization of microbial biomass and organic matter. The nine papers in part 2, "Organic Inputs and Soil Organic Matter", cover the pathways, transformations and stabilization of soil organic matter under various cropping management schemes in a variety of tropical environments. Both above and below ground factors that control organic matter inputs are covered. Nitrogen mineralization and utilization under a variety of conditions and management schemes is the major topic of part 3, "Nutrient Cycling and Processes Regulating the Transformation of Soil Organic Matter". Other papers included in this section focus on management influences and models (both conceptual and simulation) used to study organic matter dynamics. The nine papers in part 4, "Soil Organic Matter and Soil Fertility", evaluate the changes in biotic and abiotic properties as a result of management. Specific topics include potassium fixation, organic matter and aluminum interactions. Concluding remarks and conference recommendations are included at the end of the volume. The authors point out that the beneficial effects of soil organic matter are rarely
314
Book Reviews / Geoderma 63 (1994) 309-322
quantified, particularly with regard to tropical and subtropical regions. Indeed, the authors note that most organic matter research is conducted in temperate regions of the world. It becomes evident that soil organic matter research must be based on relationships between organic matter dynamics and specific characteristics of the environment. Little information is available regarding organic matter dynamics in tropical and subtropical environments. The range of subjects and spatial scales covered in this volume is very wide, and, inevitably, the amount of new information varies considerably. The comprehensive nature of the volume and the presentation is, on the whole, very clear. This volume provides basic information and a sound conceptual treatment of organic matter dynamics and should be of interest to scientists interested in the study of sustainable land management systems. EUGENEF. KELLY SSDIOO16-7061(93)EOO98-G
Fort Collins, CO., USA
N e w Z e a l a n d Soil Classification. A.E. Hewitt. 1992. DSIR Land Resources Scientific Report
No. 19. Obtainable from: Landcare Research NZ Ltd., P.O. Box 69, Lincoln, New Zealand. 133 pp. Paperback. Price $35.00. ISBN 0-477-02649-4. This book details a new national soil classification system, developed by Allan Hewitt in consultation with many soil scientists throughout New Zealand, which aims to provide a better means of communication about New Zealand soils and their utilisation. Work on the new classification was initiated in 1983 following a 5 year trial period during which Soil Taxonomy was used as a basis for soil surveys by the NZ Soil Bureau in both New Zealand and the tropical islands of the South Pacific. It was concluded that Soil Taxonomy was unsuitable for use as a primary soil classification; at that time the development of Soil Taxonomy was seen to be too slow to accommodate the needs of soil scientists in New Zealand. The trial period did, however, result in a large computer data base of fully characterised soil profiles which could be used to construct the new classification from the bottom up. The New Zealand Soil Classification went through three approximations published in 1987, 1989, and 1991. The new system follows many of the principles of Soil Taxonomy, though continuity is maintained as far as possible with the 1948 New Zealand Genetic Soil Classification of the late Normal Taylor. Soils are grouped into classes on the basis of measurable soil properties rather than presumed genesis, and differentiae are designed to allow field assignment to classes in most cases. The need for sophisticated laboratory measurements has been avoided, yet all classes are rigorously defined. The classification is hierarchical with three levels: orders, groups and subgroups. Work to define a fourth level is in progress. The introduction of the book includes brief sections on the objectives and principles of the system and correlation with other schemes of soil classification. It is followed by definitions of diagnostic horizons and other differentiae. Some are based on Soil Taxonomy, although these have been simplified considerably. Soil orders are keyed out as follows: 1. Organic, 2. Gley, 3. Ultic, 4. Podzols, 5. Allophanic, 6. Pumice, 7. Melanic, 8. Semi-arid, 9. Oxidic, 10. Granular, 11. Pallic, 12. Brown, 13. Anthropic, 14. Recent, and 15. Raw Soils.
313
France. Most references are in French but English ones have been added at the end of the list to complete the original references. This book will be useful for people whose main subject is not pedology; it raises the problems they may be faced with. This is the reason why it is written as a guide, easy to consult, describing briefly the more usual analyses proposed in catalogues of soil analysis laboratories to characterize soils samples. Although numerous English-speaking readers may not be accustomed to the methods of analyses described here, they will nevertheless be interested in this book because its main purpose is to describe and to discuss a general approach to soil properties by analytical investigation. M. HARDY
SSDIOO16-7061(93)EOlI8-F
Orleans, France
Soil Organic Matter Dynamics and Sustainability of Tropical Agriculture. Edited by K.
Mulongoy and R. Merck. Wiley, Chichester, 1993, 392 pp. Hardcover. ISBN 0-47193915-3. This book contains a series of papers presented at the proceedings of an international symposium held in Leuven, Belgium in November, 1991. The symposium summarized five years of collaborative research between the International Institute of Tropical Agriculture (IITA) and the Laboratory of Soil Fertility and Biology of the Katholieke Universiteit Leuven (K.U. Leuven), Belgium. Research focused on the biological aspects of soil organic matter dynamics and soil fertility under various cropping systems used in the tropics. The book has four major subdivisions which roughly correspond to the symposium presentations. Papers are summarized individually. The introductory paper provides a nice summary of the definitions and measurements of sustainability. It also points out the significance of soil organic matter in the assessment of sustainability and discusses factors that need to be considered if organic matter sustainability is to be related to system sustainability. The five papers in part 1, "Characterization and Quantification of Soil Organic Matter", provide comparisons of the methods used for sampling and characterization of microbial biomass and organic matter. The nine papers in part 2, "Organic Inputs and Soil Organic Matter", cover the pathways, transformations and stabilization of soil organic matter under various cropping management schemes in a variety of tropical environments. Both above and below ground factors that control organic matter inputs are covered. Nitrogen mineralization and utilization under a variety of conditions and management schemes is the major topic of part 3, "Nutrient Cycling and Processes Regulating the Transformation of Soil Organic Matter". Other papers included in this section focus on management influences and models (both conceptual and simulation) used to study organic matter dynamics. The nine papers in part 4, "Soil Organic Matter and Soil Fertility", evaluate the changes in biotic and abiotic properties as a result of management. Specific topics include potassium fixation, organic matter and aluminum interactions. Concluding remarks and conference recommendations are included at the end of the volume. The authors point out that the beneficial effects of soil organic matter are rarely
314
Book Reviews / Geoderma 63 (1994) 309-322
quantified, particularly with regard to tropical and subtropical regions. Indeed, the authors note that most organic matter research is conducted in temperate regions of the world. It becomes evident that soil organic matter research must be based on relationships between organic matter dynamics and specific characteristics of the environment. Little information is available regarding organic matter dynamics in tropical and subtropical environments. The range of subjects and spatial scales covered in this volume is very wide, and, inevitably, the amount of new information varies considerably. The comprehensive nature of the volume and the presentation is, on the whole, very clear. This volume provides basic information and a sound conceptual treatment of organic matter dynamics and should be of interest to scientists interested in the study of sustainable land management systems. EUGENEF. KELLY SSDIOO16-7061(93)EOO98-G
Fort Collins, CO., USA
N e w Z e a l a n d Soil Classification. A.E. Hewitt. 1992. DSIR Land Resources Scientific Report
No. 19. Obtainable from: Landcare Research NZ Ltd., P.O. Box 69, Lincoln, New Zealand. 133 pp. Paperback. Price $35.00. ISBN 0-477-02649-4. This book details a new national soil classification system, developed by Allan Hewitt in consultation with many soil scientists throughout New Zealand, which aims to provide a better means of communication about New Zealand soils and their utilisation. Work on the new classification was initiated in 1983 following a 5 year trial period during which Soil Taxonomy was used as a basis for soil surveys by the NZ Soil Bureau in both New Zealand and the tropical islands of the South Pacific. It was concluded that Soil Taxonomy was unsuitable for use as a primary soil classification; at that time the development of Soil Taxonomy was seen to be too slow to accommodate the needs of soil scientists in New Zealand. The trial period did, however, result in a large computer data base of fully characterised soil profiles which could be used to construct the new classification from the bottom up. The New Zealand Soil Classification went through three approximations published in 1987, 1989, and 1991. The new system follows many of the principles of Soil Taxonomy, though continuity is maintained as far as possible with the 1948 New Zealand Genetic Soil Classification of the late Normal Taylor. Soils are grouped into classes on the basis of measurable soil properties rather than presumed genesis, and differentiae are designed to allow field assignment to classes in most cases. The need for sophisticated laboratory measurements has been avoided, yet all classes are rigorously defined. The classification is hierarchical with three levels: orders, groups and subgroups. Work to define a fourth level is in progress. The introduction of the book includes brief sections on the objectives and principles of the system and correlation with other schemes of soil classification. It is followed by definitions of diagnostic horizons and other differentiae. Some are based on Soil Taxonomy, although these have been simplified considerably. Soil orders are keyed out as follows: 1. Organic, 2. Gley, 3. Ultic, 4. Podzols, 5. Allophanic, 6. Pumice, 7. Melanic, 8. Semi-arid, 9. Oxidic, 10. Granular, 11. Pallic, 12. Brown, 13. Anthropic, 14. Recent, and 15. Raw Soils.