NPK water soluble fertilizer

Due to the need of agriculture, compound fertilizer especially high concentration compound fertilizer is the inevitable trend of the development of fertilizer varieties. The early fertilizer industry in most countries was dominated by the production of unit fertilizers (fertilizers containing one nutrient element). In the United States, it was based on superphosphate, mixed (and sometimes granulated) with Peruvian guano, Chilean saltpeter, potassium salt, and some organic waste in the early 20th century. In the U.S., Western Europe, and Japan, 40 to 50 percent of N, 80 to 85 percent of P2O5, and 85 to 90 percent of K2O are supplied in the form of composite fertilizers. With the development of soil fertilizer science and agricultural fertilization technology, agriculture has been moving towards scientific fertilization. Scientific fertilization must be based on different soil types and properties, fertility levels, crop types and climatic conditions and other factors to determine the variety and amount of fertilization, so that the soil can avoid excessive application or shortage of one or several nutrients caused by waste.

A large number of elemental water-soluble fertilizers are water-dissolved or diluted, which are liquid or solid products used for irrigation and fertilization, foliar fertilization, soilless cultivation, seed dipping and root dipping, etc. But the standard does not give a precise definition of "heavy elemental water soluble fertilizer". In this standard, water - soluble fertilizer, actually refers to water - soluble compound fertilizer or compost. It is not possible to refer to simple water-soluble fertilizers such as urea and potassium chloride (in fact, these fertilizers already have national standards). Can accurately summarize its true connotation of the name should be called "water-soluble compound fertilizer", so that it is not only different from ordinary compound fertilizer, but also can contain various nutritional elements. Usually a large number of elements only refers to nitrogen, phosphorus and potassium, but the current standard requires trace elements up to 0.2~3.0%(or medium elements greater than 1.0%), and the name of "a large number of elements water soluble fertilizer" does not match. If it is called "water-soluble compound fertilizer", calcium, magnesium, sulfur and trace elements can be included. In fact, water-soluble compound fertilizer is only a part of compound fertilizer. The index of water insoluble substance can also be used to define the grade of fertilizer, and the title of "water-soluble fertilizer with large quantities of elements" can be eliminated. This is also the case in practice. For example, water insoluble matter less than 0.1% can be used in drip irrigation system, water insoluble matter less than 0.5% can be used in sprinkler irrigation system, water insoluble matter less than 5% can be used in irrigation, leaching, pouring, etc. (Very accurate relationship between water insoluble matter content and various fertilization methods needs to be verified by scientific research departments). Just make it mandatory to state water insoluble content on fertilizer packaging. In fact, it is to add a water insoluble content requirement in the standard of compound fertilizer or add a water insoluble content label in the packaging standard of fertilizer.以上翻译结果来自有道神经网络翻译（YNMT）· 通用场景