ISSN 1392-3196 / e-ISSN 2335-8947
Zemdirbyste-Agriculture, vol. 100, No. 4 (2013), p. 355–362
Energy balance of catch crops production
Pavel FUKSA, Josef HAKL, Václav BRANT
The aim of this paper was to evaluate catch crops for energy production and effectiveness in the areas with limited precipitation. Eight plant species: Brassica napus, Lolium multiflorum, Lolium perenne, Phacelia tanacetifolia, Raphanus sativus var. oleiformis, Sinapis alba, Trifolium incarnatum, Trifolium subterraneum, and un-seeded control were observed from 2005 to 2007. Energy content of biomass (MJ kg-1) and energy production (GJ ha-1) of catch crops, volunteers and weeds were determined and energy balance (inputs, gain, and effectiveness) was calculated. Energy content of above-ground biomass of catch crops (15.65–20.21 MJ kg-1) was significantly (P < 0.05) influenced by species and year. In average of 2005–2007, the total energy production was 18.19 GJ ha-1 in un-seeded control (production of weeds and volunteers) and ranged from 24.74 to 57.02 GJ ha-1 in the stands with evaluated catch crops. Catch crops represented 43–94% of the total energy production depending on plant species. Gain of positive energy balance of evaluated catch crops was influenced particularly by the year in relation to soil moisture by contrast to the un-seeded control. In all three years, positive energy balance was reached only by the stand with S. alba. P. tanacetifolia performed at the lowest value of additional energy and R. sativus performed at the highest energy accumulation in underground biomass.
Key words: calorific value, energy production, intercrop, volunteers, weed.
Full text: 100_4_str45.pdf