A Life-Cycle Approach to Characterising Environmental and Economic Impacts of Multifunctional Land-Use Systems: An Integrated Assessment in the UK

An integrated environmental and economic assessment of land use for food, energy and timber in the UK has been performed using environmental Life Cycle Assessment (LCA) and economic Life Cycle Costing (LCC), to explore complementary sustainability aspects of alternative land uses. The environmental assessment includes impacts on climate change, ecosystem services and biodiversity, all of which include soil carbon emissions. The systems explored include all processes from cradle to farm ‘gate’. The crops assessed were wheat and oilseed rape (under both organic and conventional farming systems), Scots Pine, and willow and <em>Miscanthus</em>. Food crops, particularly conventional food crops, are shown to have the highest climate-changing emissions per ha, whereas energy and forestry crops show negative net emissions. To a lesser extent, the same situation applies to impacts on ecosystems and biodiversity, with carbon storage in biomass playing a larger role than carbon in soils. The energy and forestry crops in this study show an overall beneficial environmental impact, in particular due to soil carbon sequestration, making these land uses the lowest contributors to climate change. Combining this with the non-renewable CO₂ emissions displaced will mean that energy crops have an even lower impact. Economically, conventional food crops present the highest costs per ha, followed by organic food crops, energy and forestry crops. Integrating the results from LCA and LCC shows that the climate impacts per monetary unit of all land uses are dominated by soil management and, in the case of food production, also by fertilisation. Taxes or incentives such as “carbon charging” will encourage changes in practice in these areas to improve the sustainability of land management, mainly by building up Soil Organic Carbon (SOC).