FAO CONSERVATION GUIDE     34

	Agroforestry parklands in sub-Saharan Africa
	Table of Contents

by
J.-M. Boffa

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 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-36
ISBN 92-5-104376-0

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.

Foreword

The ecological and socio-economic importance of traditional agroforestry systems is now widely recognized. These land-use systems provide various useful products for household and national economies including food and medicinal products for humans and animals, wood for construction and fuel, and cash income. They contribute to the sustainability of soil nutrient and water cycles and buffer climatic extremes. This is particularly true of agroforestry parklands, the most widespread agroforestry systems in the semi-arid zones of West Africa. Their social and ecological values also carry a high significance. This and the fact that they have been subject to severe droughts and utilization pressure in the last decades have led to a growing interest in promoting their conservation and in further improving their management to increase the benefits they provide to farmers.

A basic challenge in the field of agroforestry is how to make a tangible difference for farmers. The capacity of researchers, practitioners, conservationists and policy-makers to learn how to assist farmers to manage agroforestry parkland systems in more productive and sustainable ways relies primarily on the availability of cogent, comprehensive, up-to-date information, which reflects the complex nature of farmers' decisions. The initiative taken by FAO to contribute to a better knowledge of concepts and the synthesis of experiences relating to Soudano-Sahelian parklands reflects the awareness of the Organization of the roles and functions of these systems.

Several meetings and publications have helped research and development efforts in this field. A particularly significant event was the 1993 conference on Agroforestry Parklands of the West African Semi-Arid Lands organized by ICRAF in Ouagadougou, which brought together people from various disciplines and geographic areas. Other major initiatives include the recent ICRAF/SALWA country reports on parklands in Senegal, Mali, Burkina Faso and Niger, the 1991 ICRISAT-ICRAF workshop on Faidherbia albida in the West African semi-arid tropics in Niamey, CIRAD-Forêt's works on F. albida including the 1998 monograph on the species, and the 1998 Working Meeting on shea nut tree (Vitellaria paradoxa, karité) at FAO. The recent Vitellaria paradoxa and Parkia biglobosa monographs from the University of Wales at Bangor add to this interesting collection. In order to give a renewed impetus to the work on these systems, FAO felt that the time was ripe to attempt the production of a state of knowledge paper integrating a wide range of information on the biophysical, socio-economic and policy aspects relating to the understanding and sustainable management of parkland species and systems. Jean-Marc Boffa, who has done extensive systems-oriented research, both biophysical and socio-economic on Vitellaria parklands in West Africa was an excellent candidate to be assigned the task.

The project originated with and has been coordinated by El-Hadji Sène, Chief of Forest Conservation, Research and Education Service in the Forest Resources Division of FAO's Forest Department. Susan Braatz, then forestry officer in charge of agroforestry in the Forest Resource Division started off the process. Michelle Gauthier, replacing Susan Braatz, took up the final steps of the project. Lise Andreasen and Michel Malagnoux have provided valuable comments and been involved in its follow-up. FAO also commissioned six parkland experts, Edouard Bonkoungou, Denis Depommier, Mark Freudenberger, Amadou Maïga, Madické Niang, and Kathrin Schreckenberg, to carry out a thorough review of the document. Technical and copy-editing was undertaken by Kathrin Schreckenberg from the Overseas Development Institute in London.

This study is part of the Conservation Guides series. It is targeted at all those with an interest in rural development, particularly agroforestry practitioners and researchers, but also policy- and decision-makers in the fields of agriculture, forestry and conservation in West Africa and beyond. I hope that it will encourage more integration in approaches, a higher degree of multidisciplinarity and more practical solutions to rural needs. It will be particularly useful for people working in the Sahel and Sudan zones of West Africa, but should also be of interest to a wide range of professionals working on agroforestry systems in other regions of the world outlining, as it does, many concepts underlying the value of trees within farming landscapes. This review is also relevant to FAO's interest and involvement in the assessment of forest resources outside forests, which are of increasing importance as pressure on resources in natural forest and tree stands rises. More research cooperation in development and dialogue on parklands are still needed and FAO welcomes observations and comments from readers for inclusion in future related studies.

Jean Clément
Director
Forest Resources Division

Abstract

This document attempts to present the current state of knowledge on agroforestry parkland systems. These systems, which for many local populations are very important for food security, income generation and environmental protection, are found primarily in the semi-arid and sub-humid zones of West Africa. The document first provides a thorough description of their distribution and diversity and discusses different ways of classifying them. It also presents data on current trends in parkland development and assesses determining factors. The document then provides an in-depth analysis of biophysical tree-soil-crop interactions and the factors regulating them, and describes various improved parkland management techniques. It goes on to examine the strength and limitations of institutional arrangements as well as the constraints imposed by Sahelian forest policies on the sustainable management of parklands. The production, use and marketing of parkland products is reviewed with an emphasis on their contribution to food security, local and national income as well as social values. Overall costs and benefits of the practice of parkland agroforestry are evaluated. In conclusion, the document identifies crucial research needs and promising avenues for promoting sustainable management of parkland systems.

Illustrations

Permission to use Vitellaria paradoxa, Parkia biglobosa and Balanites aegyptiaca distribution maps was kindly provided by Bangor University and specific thanks go to Jeremy Williams for supplying the first two in the correct format. Thanks are also expressed to CIRAD-Forêt for permission to reproduce the map of Faidherbia albida in Western Senegal. Photographs were provided by Christelle Bernard, Jean-Marc Boffa, Pascal Danthu, Roberto Faidutti, Dominique Louppe, Peter Lovett, Eliot Masters, Sibidi Jean Ouédraogo, Régis Peltier and Kathrin Schreckenberg.

List of Acronyms

Food and Agriculture Organization of the United Nations
Rome, 1999 © FAO

Hyperlinks to non-FAO Internet sites do not imply any official endorsement of or responsibility for the opinions, ideas, data or products presented at these locations, or guarantee the validity of the information provided. The sole purpose of links to non-FAO sites is to indicate further information available on related topics.

This electronic document has been scanned using optical character recognition (OCR) software. FAO declines all responsibility for any discrepancies that may exist between the present document and its original printed version.

Table of Contents

FOREWORD

ABSTRACT

LIST OF ACRONYMS

INTRODUCTION

CHAPTER 1   AGROFORESTRY PARKLAND SYSTEMS

Parklands: A review of definitions and terminology

Parklands in West Africa
Areal extent
Characterization by dominant species

Faidherbia albida
Vitellaria paradoxa
Parkia biglobosa
Other important parkland species

Factors used in establishing parkland typologies
Degree of human intervention
Functional classification
Spatial analysis

Parklands as a reflection of agrosystems and ethnicity

Summary

CHAPTER 2   PARKLAND DYNAMICS

Changes in tree density over time

Natural factors
Drought
Livestock
Pests

Economic and socio-cultural driving forces

Agricultural development policies
Role of trees in agricultural development models
Mechanization
Crop introduction and development
Fertilizer policies

Demographic relations

Summary

CHAPTER 3   BIOPHYSICAL FACTORS IN PARKLAND MANAGEMENT

Tree-soil relations

Influence on soil chemistry

Savanna tree species
Parkland tree species

Influence of trees on mineral content of understorey plants
Mechanisms of soil fertility improvement

Soil microbial activity and structure
Atmospheric inputs
Nitrogen fixation
Dung deposition
Pre-existing soil fertility
Soil management practices

Nutrient enrichment with increasing tree size
Parkland density and soil fertility
Nutrient redistribution versus enrichment
Underground tree-crop interactions

Relations between woody and herbaceous plants
Influence of trees on biomass productivity
Influence of trees on grain yields of crops

Faidherbia albida, a tree with reverse leaf phenology
Soil type, topographic position and fertilization
Distance from the tree
Influence on yield components
Influence on cotton
Influence on groundnuts

Vitellaria paradoxa, Parkia biglobosa and other species with typical leaf phenology
Soil type
Influence on groundnuts and cotton
Distinctions between tree species

Cardinal directions
Tree size

Parkland tree density and ‘parkland effect’

Influence of trees on microclimate
Light interception
Temperature
Evapotranspiration and soil moisture

Seasonal variations in soil moisture
Soil moisture variations according to tree size

Air humidity
Influence of trees on species composition
Influence of trees on phenology

Summary

CHAPTER 4   IMPROVED PARKLAND MANAGEMENT

Parkland management practices
Assisted tree regeneration
Planting of parkland species
Improved fallows
Fire protection

Silvicultural techniques
Pruning/debranching
Ringing
Coppicing and pollarding
Tree fertilization

Management techniques for improved crop production
Pruning and coppicing
Organic fertilization and mulching
Tree/crop associations

Genetic improvement of parkland species

Management and conservation of parkland genetic resources

Summary

CHAPTER 5   INSTITUTIONAL FACTORS IN PARKLAND MANAGEMENT

Introduction

Traditional tenure of agricultural land
Socio-economic organization and land allocation
Modes of access to land
Land borrowing
Traditional versus state tenure security

Indigenous institutions regulating the management of parkland resources
Regulating use by outsiders
Regulating use within communities
Changing traditions
Implications

Constraints and opportunities in traditional tree tenure
Traditional rights to parkland trees on inherited land
Tree-planting on borrowed land
Commoditization of land and trees
Women's rights
Implications of traditional tenure regimes

Impact of State policy on parkland management
Forestry legislation in the Sahel
Ambiguities in forest codes
Inappropriate rules
Institutional structure
Farmers' perceptions of their rights
The neglect of pastoral practices in land policies
Implications for improved parkland management

Control of forest commons

Local participation in the fuelwood sector

Summary

CHAPTER 6   PARKLAND PRODUCTION LEVELS

Production of parkland trees
Fruit production
Foliage production
Gum production
Wood production

Summary

CHAPTER 7   SOCIO-ECONOMIC BENEFITS OF PARKLANDS

Food security
Quantitative aspects of consumption
Qualitative contribution of parkland foods

Nutritional quality
Food variety
Seasonal food balance

Health care

Economic importance of parkland products at the local level
Diversity of products
Market volume and income

Parkland products of international economic importance
Gum arabic
Vitellaria paradoxa

General description
Market constraints
International market opportunities

Social differentiation in NTFP activities
Collecting
Consumption
Processing
Marketing

Socio-cultural and spiritual values of parkland products

Analysis of costs and benefits of parkland production

Summary

CHAPTER 8   CONCLUSIONS AND RECOMMENDATIONS

The significance of agroforestry parklands

Dynamic systems

Parkland classification

Conservation and reproduction of agroforestry parklands

Biophysical interactions

A landscape with a future

REFERENCES

Boxes

Figures

Tables