ABSTRACT
This chapter discusses the various methods that have been used to measure stability and maturity of composts. To be valid, a stability method must relate to physical changes in the compost as a result of microbial degradation. More effort and research have gone into chemical methods for determining stability and maturity than into the biological or physical evaluations. The stability method should be valid for composts of different feedstocks. Maturity is a function of the organo-chemical properties of the compost as related to phytotoxicity to distinguish between phytotoxic effects due to inorganic chemicals and salinity. The use of sophisticated chemical/physical methods may provide direction to the changes that occur during composting and relate these changes to simpler stability and maturity methods. One of the earlier attempts to analyze these constituents and follow their changes during composting was carried out by Waksman using the proximate analysis to evaluate sugars and simple carbohydrates, fats and waxes, hemicellulose, cellulose.
