Assessing water supply sources using life cycle assessment: study case of lemon crop in Southeastern Spain

Resumen

The Segura River basin, in south-eastern Spain, is one of the areas with the highest water scarcity, not only in Spain but also inEurope. As a result, in such a region, farmers can have up to six different water supply sources for irrigation (surface water,groundwater, reclaimed water, desalinated brackish groundwater, desalinated seawater and inter-basin Tagus-Segura watertransfer). Moreover, water reallocation by water trading between concession holders is also possible (i.e. water markets), whichin practice represents an additional water supply source. Water markets are one of the most promising instruments for reallocatingwater resources in mature water economies since they are capable of increasing the economic efficiency of water use andreducing the economic impact of scarcity. This paper analyses the environmental impacts of production of a representative lemonorchard irrigated with each one of the water supply sources above mentioned. Lemon has been selected as it is the perennialcrop with a greater area in the basin. A life cycle assessment was used to quantify the lemon orchard global warming potential,acidification of land and water, eutrophication potential, land use and cumulative energy demand. The system boundary wasconsidered from raw material extraction to farm-gate based on lemon production.The results showed large variation in theindicators. As expected, irrigation with desalinated seawater showed the highest value of global warming potential and cumulativeenergy demand, which is justified by the high-energy requirements to produce desalinated seawater and also for higherimplementation of calcium and magnesium fertilization. In addition, the analysed environmental indicators of water marketsresources with the basin were similar to those of the inter-basin Tagus-Segura water transfer.