Decomposition of organic materials by the microorganisms which grow in the
presence of air is known as Aerobic composting. Aeration is made possible through repeated turning of compost heap top admit fresh air into decomposing organic matter. When the decomposition id complete, compost can be removed and used as organic manure or as potting medium in nurseries . For tropical condition, aerobic method is the most suitable method. There are three kinds of aerobic composting based on the frequency of turning.
1. Berkeley method is the quickest method achieved through turning and mixing of the heap. This is done generally above ground stacks where free air circulation is prevalent. Large quantity of compost can be produced within a short period. However, labour requirement is high due to frequent turning. 2. In Bangalore method, the process is initially aerobic for several days and then becomes anaerobic when turning is discontinued. This method, is generally done in pits and takes about 4-5 months. The main drawback is that the outer exposed portion of the stack will retain pathogens, pests and seeds of weeds. Hence this portion may be excluded from use or incorporated into another stack of composting. Covering the top portion with mud is also a general practice 3. In Indore method, compost is turned only for five times over a period of six months. This method is less labour intensive. Compared to anaerobic composting, aerobic method has certain advantages: 1) Aerobic composting is fast and the decomposition and maturing process will be completed within 8-12 weeks. Generally foul smelling gases or toxic chemicals are not produced. 3) Pathogen and insect pests get destroyed due to temperature produced inside the compost heap. 4) The product can be easily stored dry in gunny abs or other containers.