The drip fertigation technology for vegetables featuring the integration of water and fertilizer under mulch is a new agricultural technology which combines fertilization and irrigation based on mulching cultivation. The method is conducted by blending the fertilizer into the fertile solution and transporting it to the soil in the root area of the crops for direct absorption and utilization by the root system using the drip irrigation system at the same time of irrigation. This method can precisely control the time and amount of irrigation and fertilizer, and significantly improve the utilization rate of water and fertilizer. The drip fertigation technology for greenhouse vegetables is introduced as follows.
(1) Water source: The underground water delivery project can be implemented in greenhouses linked together. Valves are set in each greenhouses, and water pumps are controlled by microcomputer. A reservoir can be built for the single greenhouse, generally built in the side wall of the greenhouse, the volume of which is not less than 3 cubic meters.
(2) Head: Install water pump, filter, pressure regulating valve, flow regulator and fertilizer tank.
(3) Water delivery pipeline: The installation grade of the drip irrigation pipeline is determined according to water source pressure and drip irrigation area. The three-stage pipeline are generally used, namely main pipe, branch pipe and capillary pipe. The thin-walled PE pipe can be used for piping.
(4) Bypass: It has the function of regulating pressure, which is convenient to connect, and can adjust the position and spacing of drip irrigation pipes at will.
(5) The drip irrigation pipe: The dripper can be disassembled. In case of blockage, it is easy to clean. The flow in the dripper is small, and a better wetting body can be formed.
(1) The drip irrigation technology: Make irrigation plans according to the water requirements of crops and soil conditions, including irrigation quota, each irrigation time, irrigation cycle and irrigation times, etc.
(2) The fertigation technology: Determine the fertigation systems according to the nutrition physiology of crops and soil conditions, such as fertigation time, quantity, proportion, fertigation times and total amount.
(3) Water-fertilizer coupling: Determine the target yield according to the growth conditions and the yield of the previous season; formulations of fertilizer are based on the theoretical data of the crop nutrition: adjusting formulations according to soil conditions; the amount of fertilizer is calculated by the ratio of fertilizer absorption amount to the whole fertilizer under the condition of the drip fertigation; choose and match fertilizer; and the amount of fertilizer is related to the irrigation system.
(4) Technology integration: Employ in pair agronomic water conservation technologies, such as protective mulch covering and the other application of water conservation agent, as well as fertilizer conservation technologies such as the application of biological fertilizer and organic fertilizer to cultivate soil fertility, etc.