The composting or composting process can be divided into four periods, based on the evolution of the temperature:
- Mesolithic. The plant mass is at room temperature and the mesophilic microorganisms multiply rapidly. As a consequence of the metabolic activity the temperature rises and organic acids are produced that lower the pH.
- Thermophilic When a temperature of 40 ° C is reached, thermophilic microorganisms act by transforming nitrogen into ammonia and the pH of the medium becomes alkaline. At 60 ° C these thermophilic fungi disappear and sporigenic bacteria and actinomycetes appear. These microorganisms are responsible for breaking down waxes, proteins and hemicelluloses.
- Cooling. When the temperature is less than 60 ºC, the thermophilic fungi that revamp the mulch and break down the cellulose reappear. When lowering 40 ° C, the mesophiles also restart their activity and the pH of the medium drops slightly.
- Maturation It is a period that requires months at room temperature, during which secondary reactions of condensation and polymerization of humus occur.
