by N.G. Dastane
FAO Consultant
project coordinator Indian agricultural research institute New Delhi
FAO IRRIGATION AND DRAINAGE PAPER
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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-56
ISBN 92-5-100272-X
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© FAO 1978
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1. Effective rainfall and its significance
2. The pathway of rain water
3. Concepts of effective rainfall
4. Definition of effective rainfall
5. Effectiveness of rainfall
6. Factors influencing effective rainfall
Chapter II. Measurement of effective rainfall
1. Components of effective rainfall and their measurement
1.1 Rainfall and Irrigation
1.2 Surface Run-off
1.3 Rooting Depth
1.4 Deep Percolation Losses
1.5 Evapotranspiration2. Empirical methods of determining effective rainfall
2.1 Soil Moisture Changes
2.2 Daily Soil Moisture Balance Method
2.3 Integrating Gauge
2.4 The Ramdas Method
2.5 Lysimeters
2.6 Drum Technique for Rice3. Determining effective rainfall from formulae
3.1 Renfro Equation
3.2 U.S. Bureau of Reclamation Method
3.3 Potential Evapotranspiration/Precipitation Ratio Method (India)
3.4 USDA, SCS Method
3.5 Empirical Relationships
Chapter III. Application of effective rainfall data is irrigation and drainage projects
1. Irrigation project design
2. Irrigation project operation
3. Drainage projects3.1 Drainage of Excess Water
3.2 Drainage for Leaching of Salts4. Rice cultivation
5. The effect of groundwater
6. Effective rainfall in unirrigated and low rainfall, areas
1. Increasing effective rainfall
1.1 Reducing Surface Run-off
1.2 Increasing Infiltration (except in rice culture)
1.3 Building Water Storage Structures
1.4 Minimizing Peep Percolation Losses2. Increasing the effectiveness of rainfall
3. Further lines of work needed in the field of effective rainfall in agriculture3.1 Collecting Data by Setting Up Crop Lysimeters
3.2 Verification of Empirical Methods
3.3 Development of Empirical Methods in Different Areas
3.4 Utilizing Information of Effective Rainfall in Agricultural Practices
3.5 Increasing Effective Rainfall Under Field Conditions
3.6 Increasing the Effectiveness of Rainfall