Agricultural fertilizers are mainly divided into three categories:
1. Organic fertilizers
Refers to fertilizers derived from animal and plant residues or metabolites, which have the characteristics of improving soil structure and slowly releasing nutrients. Common types include:
Animal source: decomposed human feces and urine, stable manure (a mixture of livestock feces and urine and bedding), compost (fermentation of plants and soil), etc.
Plant source: green manure (plants turned over and returned to the field), cake fertilizer (oil crop residues), biogas fertilizer (residues of biogas tanks), etc.
Commodity organic fertilizer: processed from industrial or agricultural waste (such as wine lees, straw, livestock and poultry manure).
Mineral fertilizer: natural mineral source fertilizers that have not been chemically processed, such as phosphate rock powder and potash rock powder.
2. Inorganic fertilizers (chemical fertilizers)
Made through chemical synthesis or ore processing, with high nutrient content and quick effect. The main types are:
Nitrogen fertilizer: such as urea (containing 46% nitrogen), promote leaf growth.
Phosphorus fertilizer: such as superphosphate, diammonium phosphate (containing 46% phosphorus), promote flowering and fruiting.
Potassium fertilizer: such as potassium chloride, potassium sulfate, enhance stress resistance.
Compound fertilizer: contains two or more of nitrogen, phosphorus and potassium, such as triple compound fertilizer.
3. Biofertilizer
Fertilizers that use microbial activities to improve soil fertilizer efficiency, common types include:
Bacterial fertilizer: such as rhizobium agents and nitrogen-fixing bacteria agents, which fix nitrogen or decompose phosphorus and potassium through microorganisms.
Biological organic fertilizer: Add functional bacteria (such as Bacillus subtilis) to organic fertilizer, which has both soil improvement and microbial activity.
In addition, there are new functional fertilizers, such as slow-release fertilizers, water-soluble fertilizers, etc., which control nutrient release through special processes.
