|MadSci Network: Microbiology|
Absolutely. Decomposition of organic matter in natural environments is largely caried out by bacteria and fungi, using chemical reactions. Thus, heat (up to a certain degree) increases the rate of reactions. Within limits increased moisture favors increased rates of decay, but excessive water can lead to anaerobic conditions (lack of oxygen gas). Without O2, decomposition is considerably slower. Air pressure could have an influence because the effect of increasing air pressure is effectively the same as increasing oxygen concentration which would favor oxidative (aerobic) decay. Conversely, if you want to limit decay you dry things, freeze them or vaccum seal them! These are all common ways of preserving foods.
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