Published in Scientific Papers. Series A. Agronomy, Vol. LXI, Issue 1
Written by Victor ŢÎŢEI
Biomass production is one of the key sectors with significant potential for the production of renewable energy and diversification of rural economy in the Republic of Moldova. Obtaining biogas from biomass is one of the possibilities to produce renewable energy and to reduce greenhouse gas emissions. The decisive factors for the cultivation and exploitation of energy crops are the productivity, the chemical structure and the cost of production of phytomass. The genus Miscanthus in general, and Miscanthus giganteus in particular, has been selected and studied as one of the most promising energy crops in Europe, over the past two decades, because of an array of attributes including high photosynthetic efficiency, high stress tolerance, perennial growth, low nutrient requirements and high content of carbon. We investigated some biological peculiarities and the biochemical composition of Miscanthus giganteus biomass under different harvest regimes and on different dates: single mowing regime (June 16, August17, October 2) and double mowing regime (1st mowing on June and 2nd mowing on October). The samples were collected from the 3-year-old Miscanthus giganteus (cv. Titan) plants cultivated in the experimental land of the Botanical Garden (Institute). The results of our study, based on the near infrared spectroscopy (NIRS) technique, indicated that the biomass of Miscanthus giganteus harvested in June contained 1.63% nitrogen, 41.7% cellulose, 31.7% hemicelluloses, 4.9% acid detergent lignin and 7.4% ash; in August - 0.35% nitrogen, 50.1% cellulose, 32.0% hemicelluloses, 7.7% acid detergent lignin and 4.5% ash, but the biomass obtained by late single mowing in October - 0.59% nitrogen, 45.1% cellulose, 29.4% hemicelluloses, 6.6% acid detergent lignin and 6.6% ash, respectively. The chemical composition of the biomass of Miscanthus giganteus obtained during the 2nd mowing, did not differ essentially from the biomass obtained as a result of the 1st mowing in June, however, the amount of acid detergent lignin and hemicelluloses varied, reaching 5.7% and 28.0%, respectively. The biochemical methane potential of the biomass of Miscanthus giganteus, obtained during the 1st mowing in June, reached 314 L/kg, in August - 259 L/kg, of late single mowing regime in October - 277 L/kg and 2nd mowing in October - 293 L/kg, respectively.
[Read full article] [Citation]
