Subsurface Drip Irrigation is a specialized sub-set of drip irrigation where dripline or drip tape "lateral lines" (tubes buried beneath the crop rows) and supply and flushing "submains" (pipes supplying water to the lateral lines) are buried beneath the soil surface for multi-year use.
In Italy, Toro realized its first SDI system in 2001. Today, more than 20 years later, the system is able to effectively deliver water and nutrients to the crops.
The SDI technique is now being used throughout the world on a wide range of grain, forage and fiber crops including alfalfa, corn, cotton, soybeans and sugarcane.
The SDI is applicable for all those crops that can be grown under minimum tillage or sowing in hard soil (surface tillage no more than 20 cm deep).
ADVANTAGES OF SDI
Common benefits of drip irrigation include yield increases, crop quality improvement and better resource use efficiency.
These benefits are also typical in SDI applications, along with improved flexibility, convenience, and the ability to farm in drought conditions.
- Excellent Irrigation Efficiency and minimum evapotranspiration losses;
- Reduced weeds growth and significant herbicide saving;
- Multi-year reuse;
- Compatibility with minimum tillage technique;
- Access fields 24/7 since there are no pipes in the way.
SYSTEM MAIN COMPONENTS
- Reliable Filtering Station and optional water treatment system.
- End-of-line mini-valves to flush the lateral lines.
- Flow meters and manometers to monitor system operation.
It is possible to improve the characteristics of the soil and the strength of the roots by injecting air into the water flow (12 15% in volume). This practice develops the soil microflora, allowing the roots to better absorb water and nutrients.
Mazzei AirJection is designed for SDI systems. It is typically installed on the sub-mains of the system and it can deliver the correct amount of air according to the water flow.
- The preliminary design for SDI system requires a careful analysis of the water source.
- Emitters spacing and distance between the lateral lines have to be identified in relation to soil texture and crops.
- Regularly flush the lateral lines by opening the end of line mini valves.