EVALUATION OF THE EFFECT OF MICR081AL MIXTURES IN COMPOST MAKING

Abstract

Air dried grass clippings. leaves. coil' dust, saw-dust and cow dung used as orgurnc rawmaterials were treated with different microbial mixtures: a solution of Efficientmicroorganisms (EM) ([-I J. a mixture of Bacteria in powder from (T-2). The control hadonly natural microorganisms (T-O). These treatment units wcrc arranged in randomizedblock design in an in-door environment. Composting period was cight weeks. Piles wereturned weekly and samples were taken for analysis. Process was monitored by measuringthe temperature, pH. carbon dioxide evolution rate, C/N ratio and change in thc particle si zc.Weed seed germination percentage was determined with the final product.

Temperature of cornposting piles increased initially in all treatments. In EM treatmenttemperature decreased after the third week. in other two cases a temperature more than 40°c was retained till the 7th week. In all treatmcnts pH increased during thc first four weeksand later decreased to neutral range. During the first three weeks the mean CO2 evaluationrate was higher with the EM solution treated units than with the other two. The C/N ratiosignificantly reduced during the process in all three trcatments but the lowest value wasobserved in EM trcatmcnts. Further change in particle size was significantly higher in EMtreatment. Weed seeds were successfully controlled in compost processed with bacteriasuspension.

It could be concluded that the EM solution and Bacteria powder used in the studyaccelerated the process but there may be disadvantages such as high weed seed germinationand unknown undesirable effects on natural flora.