In this article we will discuss about the advantages and disadvantages of sub-surface drip irrigation.
Sub-surface drip irrigation (SDI) is a low pressure, low volume irrigation system that uses buried tubes to apply water. Applied water moves out of the tubes by soil matrix suction. Wetting occurs around the tube and water moves out in the soil all directions.
Advantages of Sub-Surface Drip Irrigation:
The potential advantages of SDI are:
1. Water conservation
2. Enhanced fertiliser use efficiency
3. Uniform and highly efficient water application
4. Elimination of surface infiltration problems and evaporation losses
5. Flexibility in providing frequent and light irrigations
6. Reduced problems of disease and weeds
7. Lower pressure required for operation.
Disadvantages of Sub-Surface Drip Irrigation:
Major disadvantages are:
High cost of initial installation and
Increased possibility for clogging.
Sub-surface irrigation is suitable for almost all crops, especially for high value fruit. Tube is installed below the soil surface either by digging ditches or by special device pulled by a tractor. Depth of installation depends upon soil characteristics and crop species ranging from 15-20 cm for vegetables and 30-50 cm for tree crops.
To avoid clogging problems, it is essential for SDI to use a 200 mesh filter for most tube material. Porous tubes need more frequent flushing. Water quality affects the system (high pH, salinity and iron may cause precipitates).
Further problems arise if water contains organic matter, bacteria or algae. For protection of the system occasional injection of acid or acid forming chemicals or chlorine at the end of the irrigation season help to stop precipitates. After the use of chemicals, the system has to run for a while to remove residual chemicals.