Control of water pollution from agriculture - FAO irrigation and drainage paper 55

Table of Contents


Edwin D. Ongley

GEMS/Water Collaborating Centre
Canada Centre for Inland Waters
Burlington, Canada

Food and Agriculture Organization of the United Nations
Rome, 1996

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ISBN 92-5-103875-9

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© FAO 1996

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Table of Contents



Acronyms of institutes and programmes

Chapter 1: Introduction to agricultural water pollution

Water quality as a global issue
Non-point source pollution defined

Classes of non-point sources

Scope of the problem
Agricultural impacts on water quality

Types of impacts
Irrigation impacts on surface water quality
Public health impacts
Data on agricultural water pollution in developing countries

Types of decisions in agriculture for non-point source pollution control
The data problem

Chapter 2: Pollution by sediments

Sediment as a physical pollutant
Sediment as a chemical pollutant
Key processes: Precipitation and runoff
Key concepts

Sediment delivery ratio
Sediment enrichment ratio

Measurement and prediction of sediment loss

Prediction models
Sediment yield
Scale problems


Chapter 3: Fertilizers as water pollutants

Eutrophication of surface waters

Role of agriculture in eutrophication
Organic fertilizers

Environmental chemistry
The point versus non-point source dilemma
Management of water quality impacts from fertilizers

Mineral fertilizers
Organic fertilizers
Sludge management

Economics of control of fertilizer runoff
Problems of restoration of eutrophic lakes

Chapter 4: Pesticides as water pollutants

Historical development of pesticides
North-south dilemma over pesticide economics
Fate and effects of pesticides

Factors affecting pesticide toxicity in aquatic systems
Human health effects of pesticides
Ecological effects of pesticides
Natural factors that degrade pesticides

Pesticide monitoring in surface water
Pesticide management and control

The European experience
Pesticide registration
The Danish example
Pesticides and water quality in the developing countries

Chapter 5: Summary and recommendations

Necessity to internalize costs at the farm level
Integrated national water quality management
Assessment methodology
Environmental capacity
The data problem in water quality
Water quality indices for application to agricultural water quality issues
Economic analysis of cost of water pollution attributed to agriculture
Information technology and decision making
Use of water quality objectives
FAO and the POPs agenda
Pesticides in developing countries


Annex 1: Pesticide inventory