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CT: Composting means the autothermic (self heating) and thermophilic biological decomposition and stabilisation of biodegradable waste under controlled conditions that result in a stable sanitised material that can be applied to land for the benefit of agriculture, horticulture or ecological improvement.
Composting can range from simple outdoor windrows (large heaps) to more mechanised and, at least partially, computer controlled systems that enclose all or some phases of composting. In-vessel composting (IVC) is a commonly used term for composting systems that enclose at least one phase of composting, which is usually the initial, highest temperature, intensively monitored phase of fast-decomposition composting. ‘housed windrows’ inside a building and ‘enclosed’ composting are terms for other composting systems operated.

S: http://www.r-e-a.net/renewable-technologies/composting (last access: 4 December 2015)

N: 1. Late 14c., compote, from Old French composte “mixture of leaves, manure, etc., for fertilizing land” (13c.), also “condiment,” from Vulgar Latin composita, noun use of fem. of Latin compositus, past participle of componere “to put together” (see composite). The fertilizer sense is attested in English from 1580s, and the French word in this sense is a 19th century borrowing from English.
2. The biochemical alteration of organic refuse from a noxious conglomerate to an innocuous and usable soil humus.
3. The composting process starts with the formation of the pile. In many cases, the temperature rises rapidly to 70-80 °C within the first couple of days. First, mesophilic organisms (optimum growth temperature range = 20-45 °C) multiply rapidly on the readily available sugars and amino acids (Figure 1). They generate heat by their own metabolism and raise the temperature to a point where their own activities become suppressed. Then a few thermophilic fungi and several thermophilic bacteria (optimum growth temperature range = 50-70 °C or more) continue the process, raising the temperature of the material to 65 °C or higher. This peak heating phase is important for the quality of the compost as the heat kills pathogens and weed seeds.
The active composting stage is followed by a curing stage, and the pile temperature decreases gradually. The start of this phase is identified when turning no longer reheats the pile. At this stage, another group of thermophilic fungi starts to grow. These fungi bring about a major phase of decomposition of plant cell-wall materials such as cellulose and hemi-cellulose. Curing of the compost provides a safety net against the risks of using immature compost such as nitrogen (N) hunger, O deficiency, and toxic effects of organic acids on plants.
Eventually, the temperature declines to ambient temperature. By the time composting is completed, the pile becomes more uniform and less active biologically although mesophilic organisms recolonize the compost. The material becomes dark brown to black in colour. The particles reduce in size and become consistent and soil-like in texture. In the process, the amount of humus increases, the ratio of carbon to nitrogen (C:N) decreases, pH neutralizes, and the exchange capacity of the material increases.

S: 1. OED – (last access: 1 December 2015). 2. TERMIUM PLUS – (last access: 1 December 2015) 3. FAO – http://www.fao.org/docrep/007/y5104e/y5104e05.htm (last access: 4 December 2015).

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CR: biomass, biomass energy, compost, manure.