World reference base for soil resources


Table of contents


FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS
Rome, 1998

84 World Soil Resources Reports

International Society of Soil Science
ISSS-AISS-IBG

International Soil Reference and Information Centre
ISRIC

Food and Agriculture Organization of the United Nations

The designations employed and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture Organization of the United Nations, the International Soil Reference and Information Centre or the International Society of Soil Science concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries.

M-41
ISBN 92-5-104141-5

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying or otherwise, without the prior permission of the copyright owner. Applications for such permission, with a statement of the purpose and extent of the reproduction, should be addressed to the Director, Information Division, Food and Agriculture Organization of the United Nations, Viale delle Terme di Caracalla, 00100 Rome, Italy.

Ó FAO, ISRIC and ISSS 1998


Contents


Foreword

Acknowledgements

Chapter 1: Background

History
Objectives
Principles
Elements of the world reference base for soil resources
Discussion

Chapter 2: Key to the reference soil groups

Key to the reference soil groups of the world reference base for soil resources

Chapter 3: Diagnostic horizons, properties and materials

Diagnostic horizons

Albic horizon
Andic horizon
Anthraquic horizon
Anthropedogenic horizons
Argic horizon
Calcic horizon
Cambic horizon
Chernic horizon
Cryic horizon
Duric horizon
Ferralic horizon
Ferric horizon
Folic horizon
Fragic horizon
Fluvic horizon
Gypsic horizon
Histic horizon
Hydragric horizon
Hortic horizon
Irragric horizon
Melanic horizon
Mollic horizon
Natric horizon
Nitic horizon
Ochric horizon
Petrocalcic horizon
Petroduric horizon
Petrogypsic horizon
Petroplinthic horizon
Plaggic horizon
Plinthic horizon
Salic horizon
Spodic horizon
Sulfuric horizon
Takyric horizon
Terric horizon
Umbric horizon
Vertic horizon
Vitric horizon
Yermic horizon

Diagnostic properties

Abrupt textural change
Albeluvic tonguing
Alic properties
Aridic properties
Continuos hard rock
Ferralic properties
Geric properties
Gleyic properties
Permafrost
Secondary carbonates
Stagnic properties
Strongly humic properties

Diagnostic materials

Anthropogeomorphic soil material
Calcaric soil material
Fluvic soil material
Gypsiric soil material
Organic soil material
Sulfidic soil material
Tephric soil material

Chapter 4: Classifying subdivisions of the reference soil groups

General principles for distinguishing lower level units
Definitions of formative elements for lower level units

References

Appendix 1: Soil horizon designations

Appendix 2: Codes for the reference soil groups and soil subunits