Drip irrigation is a semi-automatic mechanical irrigation method. With the drip irrigation equipment installed, water can be delivered to the crop root zone for irrigation by simply opening the valve and adjusting it to the appropriate pressure.
Drip irrigation saves water by 30-40% compared to surface ditch irrigation, greatly reducing soil structure damage. The temperature in the greenhouse with drip irrigation is relatively higher than that of traditional surface irrigation, which is conducive to the early growth and development of crops.
The lower humidity is beneficial for reducing the occurrence of pests and diseases, resulting in a more significant increase in yield. Generally, fruit and vegetable yields can increase by 10-20%.
Components of Drip Irrigation System:
Water Supply Device: Includes water source, water pump, flow and pressure regulator, fertilizer mixing tank, and fertilizer injector. The water entering the drip irrigation pipeline must have a certain pressure to ensure the delivery and dripping of irrigation water.
To obtain water with a certain pressure, the following methods can be adopted:
a. Utilizing existing water towers: The relative height difference between the water tower and the irrigation pipeline needs to be calculated. Generally, a water pressure of 0.1-0.2 megapascals is required, equivalent to a relative height difference of 10 meters or more between the water tower and the irrigation area.
b. Installing a pressure tank next to the well: The pressure tank has a capacity of 2-8 cubic meters. After pumping water from the well, it is pressurized to 0.2-0.5 megapascals. The pressure tank should be equipped with an automatic water replenishment device to ensure continuous and uniform water supply.
c. Simple water storage tanks: Set up simple water storage tanks near the greenhouse, such as iron barrels, water tanks, plastic tanks, cement ponds, etc., with a capacity of about 0.5 cubic meters. The height of the water storage tank should be about 1.5 meters above the ground, and water is continuously injected into the water storage tank using a mini water pump during use.
d. Direct water supply using mini water pumps.
Water Pipeline: It is the channel that guides the water from the water supply device to the drip irrigation area such as the greenhouse. For greenhouses, it is generally a two-level system, consisting of main pipes and branch pipes.
Drip irrigation pipes are directly installed on the branch pipes. The drip irrigation pipe is made of high-pressure polyethylene or polyvinyl chloride, with different specifications ranging from 25 to 100 millimeters in inner diameter.
The main pipes outside the greenhouse are buried below the permafrost layer at a depth of 0.8-1 meter. Filters need to be installed on the water pipeline to prevent rust and sediment blockage. Mesh filters are used for filtration, and pressure gauge valves and fertilizer mixing tanks (with a volume of 0.5-1 cubic meters) should also be installed. The pipelines entering the greenhouse are generally placed on the ground in front of the columns or walkways in the greenhouse.
