The Chemistry and Physics of Composting Of the many chemical elements required for microbial decomposition, carbon and nitrogen are the most important. While the initial ingredients in a compost pile might start out a bit acidic or basic, the finished compost will level off to a neutral pH . The rate at which composting occurs depends on physical as well as chemical factors.
Temperature is a key parameter determining the success of composting.
Physical characteristics of the compost ingredients, including Moisture content and Particle size , affect the rate at which composting occurs. Other physical considerations include the Size and shape of the compost pile , which affect the type and rate of Aeration and the tendency of the compost to retain or dissipate the heat that is generated. The Biology of Composting Microorganisms of the compost pile Microorganisms are the workhorses of the compost pile, breaking down organic matter to produce carbon dioxide, water, heat, and humus. Initial decomposition is carried out by mesophilic microorganisms, which rapidly break down the soluble, readily degradable compounds. In many compost piles, mesophillic microorganisms do most of the work.