The use of commercial inoculant and efficient microorganisms (EM) in small-scale composting

Abstract

The increasing of organic waste generation in institutional and domestic environments reflects the need to use practices that value these materials on site. Small-scale composting is an efficient, effective, and low-cost alternative solution for this waste treatment. In order to make on site composting accessible and disseminate its benefits, this study addresses the use of biological accelerators in small-scale composting, using leftover vegetables and fruits, spent coffee grounds and garden foliage, all generated in an educational institution. The experiment was completely random, with 4 treatments and 5 repetitions each, contemplating the composting with: 1) commercial inoculant (CI); 2) Efficient Microorganisms taken from forest soil by traditional method (EM); 3) Efficient Microorganisms taken from coffee plantation soil obtained by traditional method (EMC); 4) without inoculant (control). The analysis methodology included physicochemical and biological parameters monitoring, analysis of fertility and toxicity using the seed germination test. Results showed that, statistically, the application of inoculants in composting is not essential for the good development of the process on a small scale, under the conditions studied, which would contribute to the non-necessity of costs on additives. The use of inoculants did not change the physicochemical conditions of the process and the final compost. However, the germination index of the CI (commercial inoculant) treatment was shown as a stimulant for seed germination and growth. All parameters evaluated for the organic compound were in accordance with the standards recommended by Normative Instruction nº. 25/2009, regarding organic fertilizers.