For example, it takes place on ground surfaces such as the forest floor, where droppings from trees and animals are converted into a relatively stable humus. When organic materials decompose in the presence of oxygen, the process is called “aerobic.” The aerobic process is most common in nature. However, as anaerobic compost can have a strong odor (and may need to be aired prior to using), it is not usually the first choice for home owners. For instance, a heavy plastic bag can be used to decompose grass clippings or other high nitrogen materials, shredded leaves, kitchen trimmings, a small amount of stable manure or other compostable materials.
However, organic material can be decomposed anaerobically to produce compost. Therefore, make compost this year and use it next year. The disappearance is slow, and the material must be held for periods of six months to a year to ensure relatively complete destruction of pathogens, such as the eggs of Ascaris, nematodes which are among the most resistant of the fecal-borne disease parasites in wastes. In anaerobic decomposition the pathogenic organisms do eventually disappear in the organic mass, as a result of the unfavorable environment and biological antagonisms.
High temperatures are needed for the destruction of pathogens and parasites. The lack of heat generated in the anaerobic destruction of organic matter is a definite disadvantage if contaminated materials areused for composting. In other words, much less heat is generated in anaerobic decomposition than in aerobic decomposition. This oxidation is minor, takes place rapidly, and is of no consequence in the utilization of the material on the soil. Since anaerobic destruction of organic matter is a reduction process, the final product, humus, is subject to some aerobic oxidation when put on the soil, that is, it may appear to decompose further after being exposed to air. A small portion of carbon may be respired as carbon dioxide (C0 2). The carbon from the organic compounds which is not utilized in the cell protein is liberated mainly in the reduced form of methane (CH 4). These organisms use nitrogen, phosphorus, and other nutrients to live and to develop cell protoplasm, but they reduce the organic nitrogen to organic acids and ammonia. Organic compounds break down by the action of living organisms that do not require air in the normal sense. Putrefactive breakdown of organic material takes place anaerobically. Intensive reduction of organic matter by putrefaction is usually accompanied by disagreeable odors of hydrogen sulfide and reduced organic compounds which contain sulfur, such as mercaptans (any sulfur-containing organic compound). Anaerobic Decomposition (Fermentation)Īnaerobic decomposition takes place in nature, as in the decomposition of the organic muds at the bottom of marshes and in buried organic materials to which oxygen does not have access. Differences between aerobic and anaerobic composting are discussed below. The organisms will vary in the pile due to temperature conditions, but the goal in composting is to create the most favorable environment possible for the desired organisms. In these processes, bacteria, fungi, molds, protozoa, actinomycetes, and other saprophytic organisms feed upon decaying organic materials initially, while in the later stages of decomposition mites, millipedes, centipedes, springtails, beetles and earthworms further breakdown and enrich the composting materials.
0 kommentar(er)
