As the integrated water and fertilizer technology has developed to the present day, many agricultural productions in China have adopted this technology. However, it is only in greenhouse greenhouses that the integrated water and fertilizer technology is fully utilized.

Integrated water and fertilizer irrigation utilizes a pressure system of a water and fertilizer integration machine (or natural terrain gradient) to mix soluble solid or liquid fertilizers according to the soil nutrient content and the feeding patterns and characteristics of the crop species. The fertilized solution is then blended with irrigation water and supplied through a controlled pipeline system, allowing for uniform, timed, and quantified watering and fertilization. This process, facilitated by pipes and drip nozzles, moistens the root development and growth areas of the crops. It maintains the main root soil in a loose and suitable moisture content, and, based on the feeding requirements, soil environment, and nutrient content of different vegetables, as well as the water demand and feeding patterns during different growth stages, it provides water and nutrients at the right time and in the right amounts directly to the crops.

Integrated Water and Fertilizer Application Technology: This technology is suitable for fixed water sources such as wells, reservoirs, and water storage ponds, where the water quality is good and meets micro-irrigation requirements. It has been or can be applied in areas with established or potential micro-irrigation systems. Primarily used in facility agriculture, orchard cultivation, and large field crop cultivation like cotton, as well as other crops with good economic returns.

Integrated Water and Fertilizer Advantages:

The benefits of the water-fertilizer integration system include faster nutrient absorption and improved utilization of nutrients in irrigation and fertilization.

The product can prevent volatilization loss, slow dissolution, and slow release of fertilizer effects on the surface soil, which is drier. It particularly avoids the issue of volatilization loss for ammonium and urea nitrogen fertilizers on the soil surface, thereby saving nitrogen fertilizers and benefiting environmental protection.

So, the integration of water and fertilizer significantly enhances fertilizer utilization. According to Professor Zhang Chenglin of South China Agricultural University, the irrigation and fertilization system saves 50% to 70% of fertilizer compared to conventional methods; at the same time, it greatly reduces water pollution issues caused by excessive fertilization in facility vegetables and orchards.

Thanks to the technology's human quantitative control, it meets the "well-fed" needs of crops during their critical growth stages, eliminating any symptoms of nutrient deficiency. Consequently, it can achieve the goal of both high yield and excellent quality in production.

Principles of Water and Fertilizer Integration Technology:

Integrated water and fertilizer technology is a comprehensive technique involving multiple aspects such as farmland irrigation, crop cultivation, and soil tillage. The key principles of its program should pay attention to the following four points:

Firstly, establish an irrigation system. In the design phase, consider factors such as terrain, field blocks, units, soil texture, crop planting methods, and water source characteristics to determine the burial depth, length, and irrigation area of the pipeline system. Integrated water and fertilizer irrigation can be achieved through methods such as pipeline irrigation, sprinkler irrigation, micro-sprinkler irrigation, pressure drip irrigation, gravity drip irrigation, seepage irrigation, and small-diameter outflow. It is especially important to avoid flood irrigation, as it can lead to nitrogen loss and reduce water utilization efficiency.

Section II: Fertilization System. In the field, the design should be for quantitative fertilization, including the location, capacity, outlets, fertilization pipelines, distribution valves, water pumps, and fertilization pumps, etc.

Choose the appropriate type of fertilizer. Options include liquid or solid fertilizers such as ammonia water, urea, ammonium sulfate, ammonium nitrate, monoammonium phosphate, diammonium phosphate, potassium chloride, potassium sulfate, potassium nitrate, calcium nitrate, and magnesium sulfate; solid fertilizers should primarily be in powdered or small piece form, requiring strong water solubility and minimal impurities, generally avoiding granulated compound fertilizers (including both domestic and foreign products); if using biogas slurry or humic acid liquid fertilizer, it must be filtered to prevent pipeline blockage.

Operation of irrigation and fertilization.

1. Fertilizer Dissolution and Mixing: When using liquid fertilizers, no stirring or mixing is required. Generally, solid fertilizers need to be mixed with water and stirred into a liquid form. Separation may be necessary as needed to avoid issues such as sedimentation.

2. Fertilizer Application Control: It is crucial to control the dosage during fertilization. The appropriate concentration of the fertilizer solution should be around 0.1% of the irrigation flow. For instance, if the irrigation flow is 50 m3/acre, the fertilizer solution should be applied at approximately 50 liters/acre; excessive use may lead to crop death and environmental pollution.

3. The irrigation and fertilization process is divided into three stages: Stage one, moisten with water without fertilizer; Stage two, irrigate with fertilizer solution; Stage three, flush the irrigation system with water without fertilizer.