Drip Irrigation
Aussi appelé : micro-irrigation, trickle irrigation
Drip irrigation delivers water directly to the plant root zone through a network of low-pressure pipes and emitters, typically at rates of 1–8 liters per hour per emitter. It is the most water-efficient irrigation method available — 90–95% efficiency versus 60–75% for sprinklers and 40–60% for flood irrigation — saving 30–50% of water compared to conventional methods.
Comment fonctionne Drip Irrigation
A drip system consists of a water source, filter, pressure regulator, main line, lateral lines (often poly tubing), and emitters that meter water to individual plants. Emitter spacing matches plant spacing — 30 cm for vegetables, 50–100 cm for orchards. Modern systems run at low pressure (0.7–1.4 bar), reducing pumping costs versus sprinkler irrigation.
Beyond water savings, drip delivers four agronomic benefits. (1) Higher yields — soil stays at optimum moisture continuously, avoiding stress cycles. (2) Reduced disease — foliage stays dry, preventing many fungal diseases spread by wet leaves. (3) Fertigation compatibility — fertilizer dissolved in the irrigation water delivers nutrients precisely to roots at 20–40% lower fertilizer rates. (4) Weed suppression — only wetted zones germinate weeds; dry inter-row areas stay weed-free.
Drip is standard for high-value crops (vegetables, berries, fruit trees, vineyards) and increasingly used for row crops (corn, cotton, sugarcane) in water-scarce regions. Capital cost is higher than sprinkler (€2,000–6,000/ha installed versus €800–2,500/ha for sprinkler) but typically pays back in 2–4 seasons through water savings, yield gains, and reduced fertilizer. Maintenance requires regular filter cleaning and periodic acid or chlorine flushes to prevent emitter clogging from salts and biofilms.
Sources
- FAO (2020). Drip irrigation: operation and maintenance manual.
- International Water Management Institute (IWMI). Water productivity in drip systems.