Compost
As organic matter decomposes, it recomposes, yielding a composition known as compost. Compost is a dark, crumbly, earthy-smelling material. The production of compost involves a controlled, aerobic (oxygen-required) process that converts organic waste into a nutrient-rich soil amendment or mulch. Microorganisms feed on the materials added to the compost pile during the composting process. They use carbon and nitrogen to grow and reproduce, water to digest materials, and oxygen to breathe.[1]
Definition
late 14c., compote, "mixture of stewed fruits, a preserve," 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," from com "with, together" (see com-) + ponere "to place" (see position (n.)).
The fertilizer sense is attested in English from 1580s, and the French word in this sense is a 19th century borrowing from English. The condiment sense now goes with compote, a later borrowing from French.[2]
Historical
Technical
Per the Practical Handbook of Compost Engineering the process of "composting" is, technically:
the biological decomposition and stabilization of organic substrates, under conditions that allow development of thermophilic temperatures as a result of biologically produced heat, to produce a final product [=compost] that is stable, free of pathogens and plant seeds, and can be beneficially applied to land. Thus, composting is a form of waste stabilization, but one that requires special conditions of moisture and aeration to produce thermophilic temperatures. The latter are generally considered to be above about 45°C (113°F). Maintenance of thermophilic temperatures is the primary mechanism for pathogen inactivation and seed destruction.[3]
"Thermophilic temperatures" refers to
Production
Composting organisms require four equally important ingredients to work effectively:
- Brown Earth (carbon) is needed for energy; the microbial oxidation of carbon produces the heat required for other parts of the composting process. High carbon materials tend to be brown and dry.
- Green Earth (nitrogen) is needed to grow and reproduce more organisms to oxidize the carbon. High nitrogen materials tend to be green and wet. They can also include colourful fruits and vegetables.
- Water (any color) is necessary in the right amounts to maintain activity without causing anaerobic conditions.
- Air (oxygen) is required for oxidizing the carbon, the decomposition process. Aerobic bacteria need oxygen levels above 5% to perform the processes needed for composting.
Feedstocks
GREENS + BROWNS
Reactors
- Bokashi
- Toilets
- Moundculture
- BEAM: Biologically Enhanced Agricultural Management
high in mycelium and carbon burial; alternative to "holistic management"
Application
Sources
- ↑ 1.0 1.1 https://www.epa.gov/recycle/composting-home
- ↑ Online Etymology Dictionary, "Compost" https://www.etymonline.com/word/compost
- ↑ Haug, R.T. and Haug, H.T. (1993) Practical Handbook of Compost Engineering. Lewis Publishers, Boca Raton.
- ↑ https://en.wikipedia.org/wiki/Compost [accessed 2-2-23]