PEDI Demonstration Infiltration Unit
The Demonstration Infiltration Unit, "PEDI", is a small scale unit designed to demonstrate infiltration processes and to understand the effects of soil texture and structure on infiltration and the effects of existing moisture conditions of the soil on infiltration.
The Demonstration Infiltration Unit, "PEDI", has been developed for the comparative study of infiltration processes in the laboratory, which are essential for the study of any form of irrigation. Water movement through the soil can be seen and measured and infiltration and penetration rates can be ascertained.
This unit comprises three transparent graduated cylinders in which soil samples are placed. Water poured onto the soil surface can then be observed as it infiltrates the sample.
Each cylinder features a graduated scale so that observations may be quantified. The cylinders have a permeable perforated plate at the bottom that retains the soil samples while allowing the water to drain through and facilitates drainage without undue soil loss.
Placed under the cylinders, there is a tank to collect the water and the smaller soil particles under study.
Water is poured onto the soil surface into each cylinder and its progress through the samples can be observed.
Exercises and guided practices
GUIDED PRACTICAL EXERCISES INCLUDED IN THE MANUAL
- Determination of the principles of the relationship between the type of soil and infiltration and penetration rates.
- Comparison of the cumulative infiltration, infiltration rate and penetration depth as a function of time in different types of soil.
- Study of the empirical equations as an approximation of infiltration rate.
- Visualization of the effect of crusting on infiltration.
- Visualization of the effect of soil particle size on infiltration.
MORE PRACTICAL EXERCISES TO BE DONE WITH THE UNIT
- Study of the effect of organic matter content on the infiltration and penetration rate.
- Study of the effect of non-homogeneous soil strata on infiltration and penetration rates.
- Study of the effect of moisture content on the infiltration and penetration rate.
- Study of the effect of straw mulch on infiltration rate.
- Study of the effect of soil texture and structure on infiltration.
- Study of the effect of surface on infiltration.