2.1.2. Artificial Sub-surface Irrigation

Artificial Sub-surface Irrigation involves a network of perforated pipes or tile drains laid below the surface. Water flows through pipes and moves upward by capillary action.

Artificial sub-surface irrigation is a method used to supply water to crops from below the soil surface. This is achieved by installing a system of pipes that have small holes, allowing water to seep out into the surrounding soil. The water then moves upwards towards the plant roots due to a natural phenomenon called capillary action, which is the ability of water to flow in narrow spaces without the assistance of external forces.

Think of how a sponge absorbs water. When you dip a sponge into water, it can soak up the liquid even though it’s not submerged – this is similar to how capillary action works in soil with the help of these pipes.

Design Considerations for Artificial Sub-surface Irrigation include soil capillary properties, depth and spacing of pipes, crop root zone depth, and water quality (no clogging minerals).

When designing an artificial sub-surface irrigation system, several factors need to be considered. First, the capillary properties of the soil are important as they determine how well water can move through the soil to reach plant roots. Additionally, the depth and spacing of the pipes must be planned carefully to ensure that water is delivered efficiently to the crops. The depth of the root zone of the crops will dictate how deep the pipes should be placed. Finally, the quality of the water used is crucial; using water that contains clogging minerals can hinder the system’s effectiveness.

Imagine laying out a network of straws in a glass of water. If the straws are too far apart or too shallow, some plants will get more water than others while some may not get any at all. Similarly, if the water is dirty and has bits that can clog the straws, they won't work effectively, and water won’t reach the plants properly.

Advantages include minimizing surface evaporation, no surface interference with farming operations, and reducing weed growth.

Artificial sub-surface irrigation offers several benefits for farmers. One of the main advantages is that it minimizes evaporation from the soil surface, which means more water reaches the plant roots and less is wasted. Since the system is located below ground, it does not interfere with farming activities that take place on the surface, allowing for easier cultivation and harvesting. Furthermore, this system helps reduce the growth of weeds because the surface remains relatively dry, making it less hospitable for weeds to sprout and thrive.

Consider a sponge that is kept inside a closed container. When moisture builds up inside the container, it won’t escape into the air, just like how water is not lost to evaporation in sub-surface irrigation. This 'hidden' watering method allows crops to drink their fill while avoiding a muddy surface that weeds love!

Limitations include high installation cost, not suitable for all soil types (e.g., coarse sand), maintenance of pipes is difficult, and risk of waterlogging if not managed well.

Despite its advantages, artificial sub-surface irrigation also comes with certain drawbacks. The initial cost of installation can be quite high, making it less accessible for smaller farms. Additionally, this method is not effective in all soil types; for example, it may not work well in loose, coarse sands where water drains away too quickly. Maintenance of the pipes can also pose a challenge, as any blockages or damages can be hard to detect and fix. Lastly, if the system is not managed properly, it can lead to waterlogging, which is when the soil becomes overly saturated with water, potentially harming crops.

Imagine setting up an elaborate underground sprinkler system in your yard. While it can be highly efficient, if you don’t regularly check for leaks or clogs, you might end up with a soggy lawn in one area and a barren patch in another – too much water can drown your plants just as too little can leave them thirsty.

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