Fever phase. In the initial stage of compost production, the microorganisms in the compost are mainly of medium temperature and aerobic species, and the most common ones are non-spore bacteria, spore bacteria and molds. They start the composting fermentation process, decompose easily decomposable organic substances (such as simple sugars, starch, protein, etc.) under aerobic conditions, generate a lot of heat, and continuously increase the composting temperature from about 20°C to 40°C. It is the fever stage, or the middle temperature stage.

High temperature stage With the increase of temperature, thermophilic microorganisms gradually replace the mesophilic species and play a leading role. The temperature continues to rise, generally reaching above 50°C within a few days, entering the high temperature stage. In the high temperature stage, thermoactinomycetes and thermogenic fungi become the main species. They strongly decompose the complex organic substances in the compost (such as cellulose, hemicellulose, pectin substances, etc.), accumulate heat, and the compost temperature rises to 60-70°C, even as high as 80°C. Then most of them are hot. Microorganisms also die in large numbers or enter a dormant state (above 20 days), which plays an important role in accelerating the maturity of compost. Improper composting has only a short period of high temperature, or it does not reach high temperature at all, so it matures very slowly, and cannot reach a semi-ripe state in half a year or longer.

Cooling stage: When the high temperature stage lasts for a certain period of time, most of the cellulose, hemicellulose, and pectin substances have been decomposed, leaving complex components that are difficult to decompose (such as lignin) and newly formed humus, and the activity of microorganisms is weakened , The temperature gradually drops. When the temperature drops below 40°C, mesophilic microorganisms become the dominant species again

If the cooling stage comes early, it indicates that the composting conditions are not ideal and the plant material is not fully decomposed. At this time, you can turn over the pile and mix the accumulated materials to make them generate a second heat and temperature to promote the maturity of the compost.

The stage of decomposing and maintaining fertilizer. After the compost is decomposed, its volume shrinks and the temperature of the compost drops slightly higher than the temperature. At this time, the compost should be compacted to cause an anaerobic state and weaken the mineralization of organic matter to facilitate fertilizer retention.

In short, the fermentation process of organic compost is actually a process of metabolism and reproduction of various microorganisms. The metabolic process of microorganisms is the process of decomposition of organic matter. The decomposition of organic matter will inevitably generate energy, which promotes the composting process, increases the temperature, and can also dry the wet substrate.

Many substrates used for compost carry human, animal and plant pathogens, as well as annoying organisms such as weed seeds. During the composting process, the growth of these organisms can be effectively controlled through continuous heating for a short time. Therefore, one of the main advantages of high-temperature composting is that it can inactivate human and animal and plant pathogens and seeds.

During the compost making process, the pile should be turned if necessary. Generally, it is carried out when the temperature of the pile exceeds the peak and begins to drop. Turning the pile can remix the substances with different decomposition temperatures in the inner and outer layers. If the humidity is insufficient, add some water to promote the uniform maturity of the compost.