ii Copies of this book are available from: ICRAF International Centre for Research in Agroforestry PO Box 30677, Nairobi, Kenya Tel: +254 2 524000 Fax: +254 2 524001 Email:
[email protected] URL: www.icraf.cgiar.org or from Department of Land Resource Science University of Guelph Guelph, ON, NIG 2W1, Canada Tel: (519) 824-4120 Ext. 2456 Fax: (519) 824-5730 Email:
[email protected] URL: www.uoguelph.ca/lrs Copyright © Peter van Straaten 2002 Readers are encouraged to quote and/or reproduce material from this book for their own publications, but as copyright holder, Peter van Straaten requests due acknowledgement. Citation: van Straaten, P 2002. Rocks for Crops: Agrominerals of sub-Saharan Africa. ICRAF, Nairobi, Kenya, 338pp. Cover design by Christian Finoro. Layout and editing by Steven Sadura; copy editing and index by Susan Robertson. Cover photographs by Peter van Straaten (upper left: Mr. M. Makweba, Tanzania). Printed by Fidelity National Information Solutions Canada, Scarborough, ON, M1B 3C3, Canada. Keywords: sustainable agriculture, soil fertility management, mineral resources, sub-Saharan Africa. ISBN 0-88955-512-5 ROCKS FOR CROPS: Agrominerals of sub-Saharan Africa. Peter van Straaten University of Guelph, Guelph, Ontario Canada 2002 iv Forewords I am delighted to see the publishing of a book on a totally new subject, Rocks for Crops: Agrominerals of sub-Saharan Africa. It is seldom that geologists and agricultural scientists get together in such an effort. Sub-Sahara Africa is the only remaining region in the world where hundreds of millions of people go to bed hungry every night because of insufficient food production.