Definition of irrigation

Definition of irrigation

**Irrigation** refers to the agricultural technology activity of artificially adding water to farmland, gardens or other land to meet the water needs of crop growth or improve the soil environment. It is a vital link in agricultural production, especially in areas where natural precipitation is insufficient or uneven.

1. Purpose of irrigation

Supplement insufficient precipitation: ensure the water needs of crops in drought or seasonal water shortage areas.

Improve yield and quality: optimize water supply and promote crop growth (such as rice needs flooding, fruit trees need irrigation during critical periods).

Regulate soil environment: flush saline-alkali land, prevent frost (sprinkler irrigation), and improve soil structure.

Efficient use of resources: combine fertilization (water and fertilizer integration) to reduce water resource waste.

2. Basic methods of irrigation

According to the form of water transmission and distribution, it is mainly divided into the following categories:

(1) Surface irrigation

Principle: use gravity to introduce water into the field, flow along the surface to infiltrate the soil.

Common types:

Flood irrigation: large-scale flooding (such as rice fields).

Furrow irrigation: Water infiltrates through ditches between crop rows (such as corn and cotton).

Border irrigation: Divide farmland into small borders and irrigate in sections (such as wheat).

Advantages: Low cost and simple operation.

Disadvantages: Large waste of water resources, poor uniformity, and easy to cause soil compaction or salinization.

(2) Sprinkler irrigation

Principle: Pressurize water through pipes and spray water into droplets through nozzles to simulate natural rainfall.

Applicable scenarios: field crops, lawns, slopes, etc.

Advantages: Water saving (saving 30%~50% water compared to flooding), adaptable to complex terrain.

Disadvantages: Affected by wind, high energy consumption.

(3) Drip irrigation

Principle: Water is dripped directly to the roots of crops through pipes and drippers.

Applicable scenarios: cash crops (such as grapes, vegetables), arid areas.

Advantages: water saving (efficiency of more than 90%), precise integration of water and fertilizer.

Disadvantages: high system cost, drippers are easy to clog.

(4) Subsurface Irrigation

Principle: direct wetting of the root layer by burying underground seepage pipes or porous pipes.

Advantages: reduce evaporation loss and do not affect surface operations.

Disadvantages: complex construction and maintenance, suitable for specific soils (such as sandy loam with good permeability).

(5) Micro Irrigation

Including drip irrigation, micro-sprinkler irrigation, etc., suitable for precision agriculture (such as greenhouses, orchards).

3. Types of water sources for irrigation

Surface water: rivers, lakes, reservoirs.

Groundwater: well water, spring water.

Recycled water: treated sewage (must meet agricultural water quality standards).

Rainwater collection: rainwater is stored in reservoirs for irrigation.

4. Key principles of scientific irrigation

Water demand of crops: different growth stages require different amounts of water (e.g., flowering stage is sensitive to water).

Soil characteristics: sandy soil has poor water retention and needs frequent and small-scale irrigation, while clay soil is the opposite.

Climatic conditions: arid areas need water-saving irrigation, while rainy areas should pay attention to drainage and waterlogging prevention.

Water-saving and efficient: use drip irrigation, intelligent control and other technologies to avoid waste.

5. The significance of irrigation

Ensure food security: About 20% of the world's arable land relies on irrigation, but it contributes 40% of the output.

Coping with climate change: Alleviate the threat of drought and stabilize agricultural production.

Ecological protection: Excessive irrigation may lead to a drop in groundwater levels or soil salinization, which requires scientific management.

Summary

Irrigation is the core means of agricultural production. From traditional flooding to modern intelligent drip irrigation, technological progress is promoting the efficient use of water resources. The selection of irrigation methods requires comprehensive consideration of crop types, terrain, water sources and economic efficiency to achieve sustainable agriculture.