Correlations between Composting Conditions and Characteristics of Compost as Biofertilizer

Abstract

Among the conditions determined by various authors for compost to be used as agricultural fertilizer are: pH 6-9, EC less than 3.5mS/cm, C/N ratio 26-35, and a GI above 80-85%. This study analyses three samples of composts with different percentages of vegetable waste, sewage sludge, and sawdust. The samples were tested at the Transilvania University laboratory for 9 weeks and the test results fit the conditions mentioned above: pH 8.12- 8.57, EC 1.97-3.04 mS/cm, C/N ratio 25.9-32.8 and GI 128.6-189.5% for radish seeds and 100-182% for cabbage seeds. These test results along with the evolution of FTIR spectra of the compost samples confirm the potential for compost samples to be used as fertilizers in agriculture.