Energy aspects of agro-energy crop Miscanthus giganteus production on arable and degraded soils

Abstract

Miscantus giganteus is a perennial high/productivity grass growing as agro-energy crop. The main strategy of energy crops production is avoiding competition with food production in the same place and the highest biomass production with the lowest energy and material inputs. The aim of this study was to compare the aboveground biomass production and the energy balance for miscanthus grown at arable and degraded soils for 3 years. The field experiment was established in 2010. year at two locations in Republic of Serbia in variants A-watering and fertilizing 5 weeks after sowing (100 kg NPKha-1) and B-without any agro-technical measures. On arable soil, chernozem, yields of above-ground biomass were 9,93 (B) and 14,24 t ha-1(A) after 3 years of cultivation. On degraded soil, humogley, the yield reach 16,36 t ha-1 (B), and 16.80 t ha-1 (A). Upper heating value was 18,8 MJ kg-1 regardless growing conditions. Energy balance (energi autput -energi input) were calculated for chernozem 211,86 (A) i 145,96 (B) GJ ha-1, and for humogley 235,80 (A) i 247,30 (B) GJ ha-1 after 3 years. Experimental research results on miscanthus production in Serbia show that this kind of production is possible in country specific conditions and the challenge is Miscanthus giganteus production on degraded humogley which is no appropriate for food production.

Miscantus giganteus je višegodišnja visokoproduktivna trava koja se gaji kao energetski usev. Opšta strategija gajenja energetskih useva je da se sa određene površine zemljišta dobije što više energije uz što manje troškove proizvodnje i da gejenje energetskih useva ne bude u kompeticiji sa proizvodnjom hrane. Cilj ovog rada je da se uporede produktivnost nadzemne biomase i energetski bilansi produkcije miskntusa na plodnom i degradiranom zemljištu. Poljski ogled je postavljen na dve lokacije u Republici Srbiji 2010. godine. Praćen je prinos u ranoprolećnoj žetvi nakon prve, druge i treće godine razvoja u dve varijante: A - navodnjavanje po potrebi i đubrenje 5 nedelja nakon sadnje (100 kg NPKha-1) i B - bez primene agrotehničkih mera. Na plodnom zemljištu tipa černozem izmeren je prinos biomase 14,24 t ha-1 (A) i 9,93 (B) u trećoj godini. Na degradiranom zemljištu tipa ritska crnica prinos nadzemne biomase u trećoj godini vegetacije je 16.80 t ha-1 (A) odnosno 16,36 t ha-1 (B) . Gornja toplotna moć je 18,88 MJ kg-1. Neto energetski prinos je izračunat za plodno zemljište i iznosio je 211,86 (A) i 145,96 (B) GJ ha-1, a za degradirano 235,80 (A) i 247,30 (B) GJ ha-1 za treću godinu. Rezultati su saglasni sa literaturnim podacima i ukazuju da je u Republici Srbiji moguća energetski efikasna produkcija agroenergetskog useva Miscanthusa giganteusa. Izazov je bila viša energetska efikasnost na močvarnom zemljištu koje nije pogodno za proizvodnju hrane.