Microorganisms decayed

Ammonia is present even in unpolluted air as a result of natural biochemical and chemical processes. Among the various sources of atmospheric ammonia are microorganisms, decay of animal wastes, sewage treatment, coke manufacture, ammonia manufacture, and leakage from ammonia-based refrigeration systems. High concentrations of ammonia gas in the atmosphere are generally indicative of accidental release of the gas. 

Wood is painted in order to preserve from decay, to minimize changes in moisture content that lead to distortion, and for decoration. It is a waste of time and effort to apply expensive paints or stains to exterior wood not previously treated with preservative. Preservatives are designed to penetrate the timber to protect against microorganisms and insect attack. Modern preservatives can be over-coated with paint without problems. 

Carbonaceous Deoxygenation. In this process microorganisms, principally bacteria, enzymatically mediate oxidation of simple and complex organic substances according to first order decay kinetics. 

The properties of an organic tracing compound should minimize loss while in transit. There are two main sources of dye loss, non-adsorptive loss and adsorptive loss. Nonadsorptive losses can be due, among other reasons, to photochemical decomposition, chemical decay, pH effects, and biodegradation of the compound by microorganisms. Adsorption of the tracer onto both organic and inorganic substrates is often irreversible and can be a source of much loss. 

The burning process leaves very little solid remains only ash, made up of inorganic salts that rarely make up more than a few percent of the total mass of wood. When wood bums with a restricted supply of air, however, and there is insufficient oxygen to combine with all the carbon in the wood, the remains are made up of charcoal, a very porous and impure form of carbon. Charcoal is extremely stable it does not decay, nor is it altered by most microorganisms, and it may be preserved for very long periods of time charcoal often also preserves the morphology of the burned wood. Because of its stability, charcoal residues are often found in archaeological sites where wood was either used as fuel or otherwise burned. 

Animals living in soil range from as large as groundhogs to as small as the smallest insect and arthropod. However, for our purposes, when animals become so small that a microscope is needed to see them, they are classified as microorganisms. It is assumed that the main additions to soil from animals are urine and feces. These are indeed common additions however, all animals add hair, skin, saliva, and eventually the dead and decaying bodies of the... 

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