Irrigation is the artificial process of applying controlled amounts of water to land to assist in production of crops. It is used to aid the growing of agricultural crops, maintenance of landscapes, and reclamation of disturbed soils in dry areas and during periods of less than average rainfall.
Types of Irrigation Systems
There are various types of irrigation systems used to distribute and manage water in an efficient manner.
Surface Irrigation Systems
Surface irrigation systems distribute water by overland flow to the cropland. It involves flooding the land surface manually or through channels. Common types of surface irrigation are:
- Furrow Irrigation: Water is supplied to small, long trenches or furrows between the crops. Gravity causes the water to move across the field.
- Flood Irrigation: Water is released at one end of the field and allowed to freely flow over the entire surface area. Level fields are needed for this type of irrigation.
Pressurized Irrigation Systems
Pressurized irrigation refers to several irrigation techniques that involve applying water to the land using pipes, hoses, sprinklers or drip tubes. Some types include:
- Drip Irrigation: Water is delivered in drops or trickles through an intricate network of valves, pipes, tubing and emitters. It is the most efficient irrigation method.
- Sprinkler Irrigation: Water is sprayed over the land through pressurized sprinkler systems mimicking natural rainfall. Common types are center pivot systems, lateral move systems, traveling sprinklers and big gun sprinklers.
Other systems like manual irrigation using water cans and buckets also exist mainly for small vegetable gardens.
Purpose of Irrigation
Irrigation serves some key purposes:
- Increase Crop Yields: Additional water supply improves moisture availability in the crop root zone increasing productivity.
- Improve Crop Quality and Growth: Adequate irrigation prevents moisture stress at critical crop growth stages enhancing overall health.
- Allow Crop Diversification: Irrigation permits cultivation of more water-intensive crops than relying solely on rainfall.
- Reclaim Arid Land: Irrigation enables agricultural usage of lands with limited rainfall that support only sparse vegetation.
Key Components of an Irrigation System
Major components of an irrigation system include:
- Water Source: Surface water from rivers, lakes, ponds or underground water from wells is used.
- Conveyance System: Network of pipes, aqueducts, drainage canals or natural stream channels that delivers water from source to the farm.
- On-Farm Application: Infrastructure within the agricultural land such as furrows, sprinklers, emitters that directly applies water to crops.
- Water Use Monitoring: Measuring devices like water meters and pressure gauges to manage distribution.
- Drainage System: Removes excess water from the irrigated area preventing waterlogging and salt accumulation.
Factors Influencing Irrigation Needs
The water needs for optimal plant growth depend on:
- Climate: Temperature, rainfall patterns, humidity levels and wind speed determines water need.
- Crop Type: The type of crop, its stage of growth and the variety’s water requirement differs.
- Soil Characteristics: Water holding capacity of soil, infiltration rate, drainage pattern affects irrigation.
- Farming Method: Water need varies based on planting density, intercropping patterns and agronomic practices.
Advancements in Irrigation Technology
Some recent innovations related to irrigation technology are:
- Automation using soil moisture sensors that trigger watering only when required.
- Precision agriculture helping monitor exact field conditions using IoT and satellite data to optimize water use.
- Drip irrigation enhancements like subsurface drip that deposits water directly into the root zone.
- Micro and drip irrigation adoption to ensure very high field efficiency reducing water wastages.
With increasing pressure on limited freshwater resources, efficient irrigation is essential for sustainable agriculture now and in the future. Careful assessment of crop water requirements, irrigation scheduling and use of precision techniques is key to producing more with diminishing water supplies.