In the process of composting, two classes of microorganisms contribute. The first set of microorganisms that grow between 20 to 35ºC is called mesophiles. Mesophiles perform the initial degradation and perform curing of compost in the final phase of the process.
The mesophilic microbes grow and reproduce rapidly, producing heat during the initial phase, whereas, during the final phase of composting, they help in the maturation of degraded organic material.
Between the initial and final composting phase, there is an increase in the core temperature of the composting mixture, known as a thermophilic phase, where temperature can rise up to 55 to 70ºC.
This is caused due to rapid heat production in the initial phase of composting. Thermophiles can grow at such high temperatures and help in breaking down complex organic material.
The high temperature helps in the killing of pathogens and weeds. Having a microbial ecosystem is key to ensuring composting is an efficient solid waste management process.