by
I.P. Abrol
Director
and
J.S.P. Yadav
Central Soil Salinity Research Institute
Karnal, India
and
F.I. Massoud
FAO Soil Resources Management and Conservation
Service
Soil Resources, Management and Conservation Service FAO Land and Water Development Division
FAO SOILS BULLETIN 39
FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED
NATIONS
Rome, 1988
Cover photo: A bed and ridge method of planting trees in auger holes made mechanically with a tractor-operated auger, and for storage of rain water in sodic soils.
|
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-53
ISBN 92-5-102686-6
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© FAO 1988
This electronic document has been scanned using optical character recognition (OCR) software and careful manual recorrection. Even if the quality of digitalisation is high, the FAO declines all responsibility for any discrepancies that may exist between the present document and its original printed version.
2. ORIGIN, CLASSIFICATION AND DISTRIBUTION OF SALT-AFFECTED SOILS
2.1 Origin of salts
2.2 Classification
2.3 Mode of formation
3. SALINE SOILS AND THEIR MANAGEMENT
3.1.1 Measuring salinity status
3.1.2 Salinity and plant growth3.2 Reclamation and management
3.3.1 Rice in saline soils
3.3.2 Factors influencing tolerance of crops to salinity
3.3.3 Water management
3.3.4 Nutrient availability and uptake by plants
4. SODIC SOILS AND THEIR MANAGEMENT
4.1 Characteristics
4.2 Measuring sodicity/alkali status of soils4.2.1 pH measurement
4.2.2 Evaluating ESP
4.2.3 SAR as an index of sodicity hazards4.3 Sodic soils and plant growth
4.4 Reclamation and management4.6 Factors influencing tolerance of crops to exchangeable sodium
4.6.1 Growth stage
4.6.2 Environmental factors
4.6.3 Crop varieties4.7 Nutrient requirements of crops
4.8 Water management
5. SALINITY PROBLEMS OF THE DRYLAND REGIONS
5.1 Mode of formation
5.2 Factors influencing formation of saline seeps5.3 Prevention and management of saline seeps
5.3.1 Practices for the recharge area
5.3.2 Practices for the discharge areas
6. WATER QUALITY AND CROP PRODUCTION
6.1 Hazards associated with water quality
6.1.1 Salinity hazard
6.1.2 Sodicity (alkali) hazard
6.1.3 Toxicity hazard6.2 Salinity problems
6.3 Management practices for efficient use of high salinity water6.3.1 More frequent irrigation
6.3.2 Selection of salt tolerant crops and varieties
6.3.3 Use of extra water for leaching
6.3.4 Conjunctive use of fresh and saline waters
6.3.5 Cultural practices6.4 The sodicity (alkali) problem
6.4.1 Role of magnesium
6.4.2 Management practices for efficient use of water with sodicity hazard
7. SOCIO-ECONOMIC CONSIDERATIONS IN RECLAMATION AND MANAGEMENT OF SALT-AFFECTED SOILS
7.1 Faulty irrigation schemes
7.2 Extensive vs. intensive irrigation
7.3 Deforestation
7.4 Water pricing
7.5 Size of holding and land consolidation
7.6 Land tenure system
7.7 Role of appropriate technology