Fertigation: Precautions for fertilizer preparation

　　 1, the anti-nutritional liquor should be formulated more fertilizer used compost, since the presence of a variety of ionic liquids, the reaction may occur between various ions, thus affecting the availability of nutrients. When formulating nutrient solutions for fertigation, the solubility of the products after mixing different fertilizers must be considered. Since the fertilizer mixture and the precipitate formed mixture is reduced solubility. Two or more fertilizer tanks are used to store the fertilizers that will precipitate after mixing. 2 Temperature changes when the fertilizer is dissolved Most fertilizers will be accompanied by a thermal reaction when dissolved. As will emit heat when dissolved phosphate, urea will absorb heat dissolution, the temperature is lowered. Understanding these reactions has certain guiding significance for the preparation of nutrient mother liquor in the field.

　　 3 , the reaction of fertilizer and irrigation water Irrigation water usually contains a variety of ions and impurities. Such as calcium ion, magnesium ion, sulfate ion, carbonate ion and bicarbonate ion. When the ions inherent in these irrigation water reach a certain concentration, they react with the relevant ions in the fertilizer to produce a precipitate. The hardness of irrigation water in northern China is relatively high. For irrigation and fertilization, calcium and magnesium in irrigation water combine with phosphate ions and sulfate ions in fertilizer to form a precipitate. When the hardness of the water is large, fertilization (especially phosphate fertilizer) by the irrigation system is liable to cause sedimentation, which causes clogging of the dripper and the filter. Recommendation acidic fertilizers in irrigation systems periodically injecting an acid solution, to dissolve the precipitate, emitter prevent clogging. The hardness of water can usually be understood by measuring the conductivity of the irrigation water. When the conductivity of the irrigation water is high (greater than 2-3 dS/m ), there may be a risk of precipitation by applying phosphate or sulfate. At the same time, the addition of fertilizer (inorganic salt) to irrigation water with high conductivity may cause salt damage to crops.

　　 4. Reactions between irrigation fertilizers and equipment Because fertilizers are used in irrigation systems, the materials and fertilizers of the irrigation system are in direct contact. Some materials are easily corroded, rusted or dissolved, and some are resistant to acids, alkalis, and salts.