Provisional edition
FAO - FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS
a manual prepared jointly
by
C. Brouwer
International Institute for Land Reclamation and Improvement
and
A. Goffeau
M. Heibloem
FAO Land and Water
Development Division
|
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. |
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© FAO 1985
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.
CHAPTER 1 - BASIC TERMS AND CALCULATIONS
1.1 Introduction to surface area
1.1.1 Triangles
1.1.2 Squares and Rectangles
1.1.3 Rhombuses and Parallelograms
1.1.4 Trapeziums
1.1.5 Circles
1.1.6 Metric Conversions1.2 Surface areas of canal cross-sections and farms
1.2.1 Determination of the surface areas of canal cross-sections
1.2.2 Determination of the surface area of a farm1.5 Introduction to percentage and per mil
2.1.1 Soil composition
2.1.2 Soil profile
2.1.3 Soil texture
2.1.4 Soil structure2.2 Entry of water into the soil
2.2.1 The infiltration process
2.2.2 Infiltration rate
2.2.3 Factors influencing the infiltration rate2.3.1 Soil moisture content
2.3.2 Saturation
2.3.3 Field capacity
2.3.4 Permanent wilting point2.4 Available water content
2.5 Groundwater table2.5.1 Depth of the groundwater table
2.5.2 Perched groundwater table
2.5.3 Capillary rise
CHAPTER 3 - ELEMENTS OF TOPOGRAPHY
3.1.1 Definition
3.1.2 Method of expressing slopes
3.1.3 Cross slopes3.4.1 Description of a map
3.4.2 Interpretation of contour lines on a map
3.4.3 Mistakes in the contour lines
3.4.4 Scale of a map
CHAPTER 4 - RAINFALL AND EVAPOTRANSPIRATION
4.1.1 Amount of rainfall
4.1.2 Rainfall intensity
4.1.3 Rainfall Distribution
4.1.4 Effective Rainfall4.2.1 Evaporation
4.2.2 Transpiration
4.2.3 Evapotranspiration
4.2.4 Factors influencing crop evapotranspiration
5.1 Main intake structure and pumping station
5.2 Conveyance and distribution system
5.3.1 Surface irrigation
5.3.2 Sprinkler irrigation
5.3.3 Drip irrigation
6.1 Need for drainage
6.2 Different types of drainage
7.3 Crops and saline soils
7.4 Sodicity
7.5 Improvement of saline and sodic soils7.5.1 Improvement of saline soils
7.5.2 Improvement of sodic soils7.6 Prevention of salinization
7.6.1 Irrigation water quality
7.6.2 Irrigation management and drainage