core components FOR FERTILIZER SYSTEM

Four core components: none can be missing.
The integrated water and fertilizer drip irrigation system consists of four parts: water source project, headworks, water transmission and distribution network, and field irrigation devices. Each part directly affects the system efficiency, and it is especially necessary to adapt to the rainy environment in the south.
1. Water source engineering: filtration is the first line of defense.
Southern water sources often contain silt and algae, requiring priority treatment. A two-stage filtration system of "centrifugal filter + disc filter" is recommended: the centrifugal filter removes silt (particle size > 50μm), while the disc filter intercepts algae and organic matter (50-120 mesh). Installation should be close to the water source and before the fertilizer applicator to prevent clogging.
2. Headquarters: The system's "brain" and "heart"
• Pressurization equipment: Centrifugal pumps are generally optional. In mountainous areas, multi-stage centrifugal pumps are required to ensure head (≥0.2MPa). Vibration damping measures should be taken during installation, and an 80-mesh filter should be added to the inlet to prevent impurities.
• Fertilizer application equipment: Small farmers in the south should choose differential pressure fertilizer tanks (low cost), while large-scale planting is recommended to use injection fertilizer machines (accuracy ±2%). Note: Venturi fertilizer applicators are sensitive to water pressure. During the rainy season, when the water pressure fluctuates greatly, the concentration may be uneven, so a pressure regulating valve is required.
• Control equipment: The intelligent controller needs to be connected to soil moisture and rainfall sensors and set to the "no irrigation after rainfall" function (automatic irrigation stop when rainfall > 10mm). The distribution box should be installed in a well-ventilated and dry place to avoid short circuits due to moisture during the rainy season.
3. Water supply and distribution network: Corrosion resistance and pressure resistance are key.
The main pipeline should be made of PE pipe (pressure resistant 0.8MPa), and the branch pipes should be made of embedded drip irrigation tape (wall thickness ≥0.2mm). In the rainy south, the soil is prone to softening, so the pipeline needs to be buried at a depth of at least 30cm, and elbows should be used at bends to prevent cracking. An air vent valve should be installed every 50 meters, and the drain valve should be opened after the rainy season to drain accumulated water from the pipeline and prevent corrosion.
4. Field irrigation system: adaptable to different crops and terrains.
• For vegetables and flowers, use porous drip irrigation tape (15cm spacing); for fruit trees, use pressure-compensating drippers (flow rate 2-4L/h). • In hilly and mountainous areas, pressure-compensating drippers must be used to ensure that the flow rate variation coefficient is <5% within a slope of 15°, avoiding water shortage at higher elevations and waterlogging at lower elevations.
(II) The core principle of "three-fixed" management: the underlying logic of precise management
The essence of drip irrigation systems lies in "quantitative, timed, and root-specific" irrigation, which is also the key technical approach for water and fertilizer control in rainy southern regions.
Quantitative: Data-driven precision supply uses sensors to monitor soil moisture content and EC value, and calculates the dosage based on crop nutrient requirements. For example, when the potassium requirement of tomatoes surges during the fruit expansion period, the system automatically adjusts the potassium fertilizer ratio to 40%; when the soil EC value is >1.5mS/cm (excessive salinity), fertilization is immediately suspended and the soil is flushed with clean water.
2. Timely Irrigation: Following Crop and Weather • Timely Irrigation During Growth Stage: Irrigate every 3 days during grape budding and every 2 days during ripening. • Weather Coordination: Increase irrigation volume by 10% during high temperatures (>35℃), and adjust intervals according to rainfall during the rainy season. Applying this strategy to cornfields in Gansu Province reduced irrigation frequency by 60% during the rainy season.

Let's first understand a key term: head – which is the force with which a water pump can "push" water far and "lift" it high. For example, a head of 0.2 MPa can send water to the height of a two-story building, or push it to the edge of a field 100 meters away (in mountainous areas, the height of the slope must also be taken into account).
1. Plain areas: Choose a centrifugal pump; it's sufficient and saves money.
If your land is on a plain (such as rice paddies or vegetable fields in the middle and lower reaches of the Yangtze River), where the terrain is flat and the water doesn't need to climb too high or travel too far, a centrifugal pump is sufficient. These pumps are inexpensive (generally a few hundred yuan) and provide a stable water output. For example, for a 3-acre vegetable field, a centrifugal pump with a flow rate of 2 cubic meters per hour can ensure that every drip irrigation tape has water.

2. Mountainous/Hillary terrain: A multi-stage centrifugal pump is necessary; it needs to be powerful enough to be effective.
n places like the tangerine orchards in Guangxi and the tea plantations in Yunnan, which are mostly located on mountains with undulating terrain, some areas are more than 10 meters higher than the water source. Ordinary centrifugal pumps simply cannot move the water – either the drippers at higher elevations have no water, or the water flows extremely slowly. In such cases, a multi-stage centrifugal pump is needed. It is essentially several small pumps stacked together, which is extremely powerful and can easily exceed 0.2 MPa in head, ensuring a uniform water flow whether it is trees on the mountaintop or vegetables at the foot of the mountain.
3. Two essential things to do during installation: prevent vibration and prevent impurities.
The core requirements for fertilization equipment are twofold: cost-effectiveness (for small farmers) and precision (for large-scale operations), while also being able to withstand the "water pressure fluctuations" during the rainy season in the south.
Large-scale planting (tens to hundreds of acres): Choose an "injection fertilizer applicator" for precision and labor-saving results.
• High precision: The error is no more than 2% – for example, if you set the amount of fertilizer to be applied per acre to 8 jin (4 catties), it can ensure that all plots receive approximately 8 jin, with little variation; • No need for manual fertilization: simply pour the fertilizer solution into a large container (such as a 200-liter container), and the machine will automatically "inject" the fertilizer solution into the main water pipe according to the ratio. You can also set the fertilization time (such as automatic fertilization from 6 am to 8 am); • Can mix fertilizers: for example, you can add nitrogen, phosphorus, potassium, and trace elements at the same time, and the machine will automatically mix them evenly without human intervention.

The control equipment is the "brain" of the drip irrigation system, which can automatically determine whether or not to water, eliminating the need for people to turn the valves on and off every day, making it especially suitable for the rainy season in the south.
• Soil Moisture Sensor: This sensor measures soil moisture by inserting a probe (shaped like a metal rod) into the ground (20-30 cm deep, for example, next to the roots of a fruit tree or in the middle of a ridge for vegetables). It measures the soil moisture content in real time. For example, if you set the system to "water when soil moisture content is below 60%", the sensor will tell the controller "it's time to water" once the soil is low, and the controller will automatically open the solenoid valve; when the water level is sufficient (for example, 80%), it will automatically turn off the water.
• Rainfall sensor: Measures how much rain has fallen to prevent unnecessary irrigation. This sensor should be installed in an open area (such as on a field ridge, not blocked by trees) to measure the amount of rain each time. In southern regions, heavy rains are common during the rainy season. If the sensor detects more than 10 millimeters of rain (roughly equivalent to 1 millimeter of water in a disposable cup), it will send a signal to the controller to automatically stop irrigation.