Composting agroindustrial waste inoculated with lignocellulosic fungi and modifying the C/N ratio

Abstract

The current disposal of waste involves a strong environmental impact that can be minimized by recycling these materials. Composting is one of the best options to achieve this purpose. The objective of this work is to evaluate the effect of the inoculation of Trichoderma harzianum and Aspergillus sp. in the composting process of bagasse of maguey mezcalero (BM-Agave angustifolia Haw.) and bagasse of sugar cane (BC-Saccharum officinarum L.), both with reduced C/N ratio. During 2012, in Santa Cruz Xoxocotlan (Oaxaca, Mexico), an experiment was developed under a completely randomized design. The composting process of BM and BC, inoculated with the fungi T. harzianum and Aspergillus sp., including an uninoculated control, was monitored. For both residues, the C/N ratio was modified with the addition of bovine manure. The duration of the experiment was 133 days. The temperature of the masses in fermentation was recorded every week. Samples were taken in triplicate for analysis on days 0, 37, 70, 103 and 133 after the start of the process. The addition of bovine manure was enough to reduce the value of the C/N ratio and reach the thermophilic phase in a few days. The inoculation with T. harzianum and Aspergillus sp., reduced the degradation time of BM but not BC. Aspergillus sp., Generated greater degradation in both residues. BM reached C/N values that qualify it as a mature compost as of day 103 of composting, this was not the case with BC.