Relationship between cation-exchange capacity and degree of maturity of city refuse composts

Abstract

An attempt was made to estimate the degree of maturity of city refuse composts by measuring their cation-exchange capacity (CEC). The CEC of the city refuse compost increased for the first 7 days after commencement of the fermentation process, decreased for the next 2 days, and then increased again gradually up to the end of the piling period. A highly significant negative correlation was noted between the CEC and C/N ratio of the city refuse composts (r=-0.903***). Regression analysis yielded the relationship: In CEC=7.02-1.02 In C/N The CEC values of the city refuse composts, which were considered to have been sufficiently matured for application, were greater than about 60 me/ 100 g of ash-free material.