FAO FERTILIZER AND PLANT NUTRITION BULLETIN 15

FAO FERTILIZER AND PLANT NUTRITION BULLETIN 15

Scaling soil nutrient balances
Enabling mesolevel applications for African realities

   
FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS
Rome, 2004
   
 

Table of Contents


Cover photographs:

Hedgerow intercropping, Ghana. FAO/18309/P. Cenini.
Coffee field, Kenya. E. Smaling.

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ISBN 92-5-105237-9
ISSN 0259-2495

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Contents

Foreword

Acknowledgements

Preface

Acronyms

Glossary

Chapter 1. Introduction

Rationale
The nutrient balance model
Objective
Structure

Chapter 2. Study area descriptions

Country and study area selection
Ghana

Cocoa-based farming system
Economic importance

Kenya

The tea - coffee - dairy farming system

Mali

The cotton-based farming system

Chapter 3. Methods

Macrolevel

Land-use map
Model parameters
Fallow

Mesolevel

General procedure
Ghana
Kenya
Mali

Microlevel

Overview

Calculation of soil nutrient stocks

Chapter 4. Results

Macrolevel
Ghana
Kenya
Mali
Mesolevel

Cocoa-based farming system in Ghana
Tea - coffee - dairy - based farming system in Kenya
Cotton-based farming system in Mali

Microlevel

Farms in Embu District, Kenya
Villages in Mali-Sud, Mali

Chapter 5. Discussion

A comparison of macrolevel methodologies: 1990 and 2003
Comparing macro - meso and micro - meso levels
Comparing the mesolevel between countries
Data problems

Macrolevel
Mesolevel
Microlevel

Modelling problems

Land-use map
Erosion modelling
Nutrient-balance calculations

Shortcomings and caveats

Validation
Gaps
Specific problems for each scale level
Presentation of outcomes
Usefulness for policy-makers

Impact

Bibliography

Annexes

Annex 1. Nutrient content values of manure from literature
Annex 2. Reference values for K-leaching regression model
Annex 3. Rooting depth
Annex 4. Reference values for gaseous losses
Annex 5. A procedure for LAPSUS modelling
Annex 6. Soil properties - FAO74 classification
Annex 7. Data used for macrolevel nutrient balances in a 2003 FAO study on Ghana, Kenya and Mali
Annex 8. Results of the macrolevel nutrient-balance calculations from a 2003 FAO study of Ghana, Kenya and Mali
Annex 9. Data used for mesolevel nutrient balances from a 2003 FAO study of Ghana, Kenya and Mali
Annex 10. Results of the mesolevel nutrient balance calculations from a 2003 FAO study of Ghana, Kenya and Mali
Annex 11. Abstracts of presentations from a 2003 workshop in Nairobi on scaling soil nutrient balances

FAO technical papers

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