Page 32 - soil-plant-water relationship and water requirement
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SOIL-PLANT-WATER RELATIONSHIP AND WATER REQUIREMENT
CHAPTER 3
3.0 SOIL MOISTURE CONTENT IN THE SOIL.
3.1 INTRODUCTION
To produce each kilogram of solids, plants need to absorb a few hundred kilograms of
water, which then water will be lost through evaporation and transpiration.
For plants, the ability of soil to store water in the root zone is not so long, the water
should be added to replace water lost or absorbed.
Because water is held in the pores between soil particles, the greatest amount of water
that a particular soil can hold is equal to its porosity (total volume of pores).
3.2 SOIL WATER AND SOIL WATER CONSTANT
There are three types of soil water:
• Gravitational water
• Capillary water
• Hygroscopic water:
Each type is affected by different forces that act on the water in soil
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