Preface

The purpose of this publication is to show how conservation agriculture can increase crop production while reducing erosion and reversing soil fertility decline, improving rural livelihoods and restoring the environment in developing countries. Soil organic matter and biological activity in the rooting zone, stimulated by continual additions of fresh organic material (crop residues and cover crops) are the basis of conservation agriculture, as described in the first chapter.

A review of conservation-effective systems of land use in Africa and Latin America is used to present a set of conditions necessary for farming systems to be conservation-effective and sustainable in the long run. As described in the second chapter, these experiences have demonstrated that the development of intensive production systems in the tropics is technically feasible and economically profitable, while improving the quality of the natural resources and protecting the environment. These production systems allow a more adequate land use, which in turn generate more nutrients in the soil and improve its water retention capacity. Additionally, agro-biodiversity and carbon sequestration are enhanced through these conservation-effective systems.

The farming systems represent a wide range of geographic and resource features and contrasting sociological conditions. They include the reduction or elimination of slash and burn in Honduras, the development of minimum tillage and direct drilling practices on small farms in Brazil, the liberation of areas through intensification of the livestock sector in Costa Rica, the mass adoption of zero tillage practices in El Salvador, biomass transfer to increase soil fertility in Kenya, the use of stover for both livestock and conservation purposes in the United Republic of Tanzania, a historical perspective of soil and water conservation in Malawi and the gradual improvement of poor agricultural lands in Ethiopia. Farmers have responded rapidly to market opportunities where they have been confident that they can sell their entire produce that is surplus to family requirements.

As shown in the third chapter, adaptations by farmers, either in their farming system or in the new technology, have to be supported by institutions, extension services, research and policies. All cases illustrate the importance of cover crop species in the farming system, but in general these species have not been adequately studied. Much research has been weak on socio-economic variables or even ignored them. This has often resulted in inappropriate promotional strategies or messages and a poor understanding by policymakers of possibilities for improved use of natural resources. In all cases the role and policies of governments have been of crucial importance, particularly with regard to creation of farmers' groups, land rights, input supply and credit schemes, incentives and penalties, and availability of and accessibility to information.

The cases demonstrate the need for policy environments, institutions, and practices to be integrated to meet the demand for food, to reduce poverty, and to utilise resources in an environmentally, socially, and financially sustainable way. They illustrate the importance of production systems that are capable of continually adapting to changing social, economic and environmental conditions. Additionally, the cases show the importance of reliable support facilities to facilitate the transition of farms from subsistence to more intensive systems of farming.

Acknowledgements

This publication which was prepared by Alexandra Bot, FAO Consultant, and José Benites, Technical Officer, Land and Plant Nutrition Management Service, is based on interviews with many farmers, scientists, and senior managers of public and private institutions visited in Brazil, Costa Rica, El Salvador, Honduras, Kenya, Malawi, United Republic of Tanzania, Zimbabwe and South Africa. These people are involved in ongoing projects of international organizations, such as FAO and the World Bank, or of non-governmental and governmental organizations in the mentioned countries.

The authors would particularly like to acknowledge the invaluable help provided by the main collaborators in the countries covered:

Telmo Amado (Federal University of Santa Maria, Brazil); Roberto Azofeifa, (FAO, Costa Rica); Bill Berry (KwaZulu-Natal Department of Agriculture and Environmental Affairs, South Africa); Brian Birch (KwaZulu-Natal Department of Agriculture and Environmental Affairs, South Africa); Andreas Böhringer (ICRAF, Malawi); Trent Bunderson (Washington State University, USA); Brian Burgess (Malawi); Mario Chavez (Ministry of Agriculture and Livestock, Costa Rica); Rodney Cheatle (Farmers Own Ltd, Kenya); Ian Cherret (FAO, Honduras); Horacio Chi (Ministry of Agriculture and Livestock, Costa Rica); Christina Choto (Centro de Tecnología Agrícola, Ministerio de Agricultura y Ganadería, El Salvador); Edward Chuma (Institute for Environmental Studies, Zimbabwe); William Critchley (Vrije Universiteit Amsterdam, The Netherlands); Diógenes Cubero (FAO, Costa Rica); Pieter Dercksen (FAO, Costa Rica); Michelle Deugd (FAO, Honduras); Hinton Estates (Agriway, Zimbabwe); Jim Findlay (Agrecon Consultants, South Africa); German Flores (Lempirasur, Honduras); Valdemar Hercilio de Freitas (EPAGRI, Brazil); Jorge Garay (Lempirasur, Honduras); Amadu Hiang (ICRAF, Kenya); John Landers (Associação de Plantio Direto no Cerrado, Brazil); Wilfred Mariki (Selian Agricultural Research Institute, Tanzania); Nicholaus Massawe (Selian Agricultural Research Institute, Tanzania); João Mielniczuk (University of Porto Alegre, Brazil); Vincent Mkandawire (Ministry of Agriculture and Irrigation, Malawi); Osmar de Moraes (EPAGRI, Brazil); Ant Muirhead (No Till Club, South Africa); Qureish Noordin (ICRAF, Kenya); Alan Norton (Agriway, Zimbabwe); Brian Oldreive (Agriway, Zimbabwe); José Miguel Reichert (Federal University of Santa Maria, Brazil); Bill Russell (No Till Club, South Africa); Gustavo Sain (CIMMYT, Costa Rica); Milton da Veiga (EPAGRI, Brazil); Jan van Wambeke (FAO, El Salvador); Richard Winkfield (Agricultural Research Trust, Zimbabwe).

Several people contributed to the development of this publication. The authors would like to acknowledge the assistance of Francis Shaxson, Richard Fowler, Romualdo Hernández, Paul Mueller, Rob van Haarlem and Willem Hoogmoed. The valuable comments provided by Robert Brinkman, Sally Bunning, Rudy Dudal, Theodor Friedrich and Petra van de Kop on draft versions of the document are highly appreciated. In the production of this publication, the authors have been effectively assisted by Sandrine Vaneph and Lynette Chalk-Contreras.

Acronyms

ABEAS	Brazilian Association for Higher Education in Agriculture
ACT	African Conservation Tillage network
ABHL	Association for Better Land Husbandry
ARC	South African Agricultural Research Council
CAT	Clube Amigos da Terra
CCD	Convention to Combat Desertification
CGIAR	Consultation Group for International Agricultural Research
CIDA	Canadian International Development Agency
CIMMYT	International Maize and Wheat Improvement Center
EPAGRI	Empresa de Pesquisa Agropecuária e Difusão de Tecnologia de Santa Catarina
FAO	Food and Agriculture Organization of the United Nations
FARMESA	Farm-level Applied Research Methods Programme for East and Southern Africa
FEBRAPDP	Brazilian Federation for Direct Planting into Crop Residues
GO	Governmental Organization
GTZ	German Agency for Technical Cooperation
ICRAF	International Centre for Research in Agroforestry
IFDC	International Fertilizer Development Center
IITA	International Institute of Tropical Agriculture
MAFE	Malawi Agroforestry Extension Project
NAP	National Action Plan
NEAP	National Environmental Action Plan
NGO	Non-Governmental Organization
NSSD	National Strategies for Sustainable Development
PTD	Participatory Technology Development
SADC	Southern African Development Community
SARI	Selian Agricultural Research Institute
SFI	Soil Fertility Initiative
ZFU	Zimbabwe Farmers Union
ZTAT	Zero Tillage Association for the Tropics