Investigations of the energy efficiency of the production of winter wheat and sugar beet in Europe

摘要: Energy balance sheets were calculated based on input data from 76 winter wheat and 21 sugar beet field experiments between 1989 1997. N rates applied varied 0 to 230 kg/ha of for 200 beet. The total energy consumption was the production systems including manufacture fertilizers, seeds, plant protection substances machinery, transport factory all on-farm activities. output in form harvested biomass using physical combustion value different metabolic components grain A linear relationship found increasing into system fertilizer application. In absence fertilization, 7.5 GJ/ha 8 This increased 17.5 16 at highest fertilization. At each intensity, defined as fertilization level, much higher than input. output/input ratio 6 13 11 29 variation dependent intensities growing conditions. Highest observed low intensity. net yield with obtain maximum approximately equal required achieve economic optimum or extractable yield. calculation efficiency factor application revealed that amount obtained through increase due exceeds least five times