Life Cycle Analysis of field production of fibre hemp, the effect of production practices on environmental impacts

Life Cycle Assessment (LCA) was used, to.,assess the environmental impacts of field production of fibre hemp and seven other crops in France. The production of 1 ha of hemp yielded a eutrophication potential of 20.5 kg PO4-equivalents, a global warn-ling potential,of 2330 kg CO2-equivalents, an acidification potential of 9.8 kg SO2-equivalents, a terrestrial ecotoxicity potential of,2 3 kg, 1, A-dichlorobenzene-equivalents, an energy use of 11.4 GJ, and a land use of 1.02 ha.year. A comparison of hemp (low impacts), wheat (intermediate impacts) and sugar beet (high impacts) revealed that the crops were similar for the relative contributions of emitted substances and resources used to impacts, and for the relative contribution of processes to impacts. A reduction of the impacts of hemp production should focus on eutrophication, and consider the reduction of climate change, acidification and energy use as secondary objectives. Given this objective, the overall environmental effect of the substitution of mineral fertiliser by pig slurry is negative. The introduction of reduced tillage is of interest, as it decreases energy use, acidification and climate change. Measures leading. to a reduction in NOS leaching are highly interesting, as they strongly decrease euttophication Implications for hemp breeding are discussed.