What are the main ingredients of chemical fertilizer
1, nitrogen fertilizer: that is, with nitrogen nutrients as the main component of chemical fertilizer, including ammonium bicarbonate, urea, ammonium, ammonia, ammonium chloride, ammonium sulfate, etc.
2. Phosphate fertilizer: that is, the chemical fertilizer with phosphate nutrients as the main component, including ordinary calcium superphosphate, calcium and magnesium phosphate fertilizer, etc.
3, potassium fertilizer: that is, with potassium nutrient elements as the main component of the chemical fertilizer, the current application is not much, the main varieties are potassium chloride, potassium sulfate, potassium nitrate, etc.
4, compound, mixed fertilizer: that is, fertilizer contains two kinds of fertilizer three elements (nitrogen, phosphorus, potassium) binary compound, mixed fertilizer and containing nitrogen, phosphorus, potassium three elements of ternary compound, mixed fertilizer, which mixed fertilizer in the country quickly promoted.
5, trace element fertilizer and some medium element fertilizer: the former such as containing boron, zinc, iron, molybdenum, manganese, copper and other trace elements of fertilizer, the latter such as calcium, magnesium, sulfur and other fertilizers.
6. Fertilizer beneficial to some crops: such as steel slag silicon fertilizer applied on rice, cobalt fertilizer applied on legume crops, and agricultural rare earth applied on sugarcane and fruits, etc.
What are the hazards of chemical fertilizers
1. Damage to the crops
Fertilizer is composed of a variety of different salt, so long-term and large application of these fertilizer composed of salt, when fertilizer into the soil, will increase the concentration of soil solution and produce osmolarity of different size, crop root cells not only cannot absorb water from the soil solution, instead of the water in the cytoplasm back into the soil solution, lead to crops. A typical example is the crop "burning seedlings"
After the large application of pesticides, pesticide residues or deep groundwater, also cause pollution to the water source. In recent years, the low price of garlic is caused by excessive pesticide residues and foreign buyers cancel the acquisition. Our own food may not be qualified in the test, but the consciousness of the domestic people is not so high, and then the cost of their own testing is too high. Ordinary people can not afford it.
2. Environmental pollution
① Eutrophication of rivers, lakes and inland sea. The cause of water eutrophication is mainly the increase of nitrogen and phosphorus content in the water, which causes the excessive growth of algae and other aquatic plants.
② The soil is contaminated and its physical properties deteriorate. Long-term excessive and simple application of chemical fertilizer, will acidify the soil. The soil solution increases the amount of organic and inorganic complex on the soil microgroup, and replace Ca 2, Mg2, so that the soil colloid dispersion, the soil structure destruction, the land compaction, and directly affect the agricultural production cost and the yield and quality of crops.
③ Increased toxic ingredients in food, feed, and drinking water. The biological toxicity of nitrite is 5~10 times greater than that of nitrate, and the N-nitroso compounds formed by combining nitrite and amines are strong carcinogens (see N-nitroso compounds and cancer). The amount of nitrogen compounds in well water or river water in areas where fertilizer is used will increase or even exceed drinking water standards. Excessive fertilizer application to the soil can increase the nitrate content in crops such as vegetables and grasses. The nitrite content in food and feed is too high, causing poisoning accidents in children and livestock. Chemical fertilizer also contains some other impurities, such as phosphate ore containing cadmium 10~100ppm, 5~10ppm containing lead, these impurities can also cause environmental pollution.
④ Nitrogen oxides are increased in the atmosphere. When applying nitrogen fertilizer used in farmland, a considerable amount will volatilize directly from the soil surface into gas and into the atmosphere. And quite a few of the soil in the form of organic or inorganic nitrogen, in the soil microorganisms, the action will be transformed from insoluble, adsorption and water-soluble nitrogen compounds into nitrogen and nitrogen oxides, into the atmosphere. In order to prevent environmental pollution, the applied chemical fertilizers should be controlled and managed.