Seasonal irrigation volumes and water footprint in a Mediterranean peach orchard

The water footprint of a product (WFP) has been proposed as indicator for quantifying the impact of production or consumption of goods and a tool to drive consumers' choices. Also it may serve to encourage the efficient use of fresh water. This is highly desirable in agriculture because of its high demand for fresh water, reaching 80% of total use. This study provides an assessment of the total water footprint (WFPtot) and its blue, green and grey components, at the orchard gate of a drip irrigated Mediterranean peach orchard located in southern Italy. The area has dry summers and an average of 590 mm of annual rainfall. The orchard was managed according to conventional (C) (soil tillage, mineral fertilization, empirical irrigation) and innovative (IN) practices (cover crops, recycle of pruning material, compost application and postharvest regulated deficit irrigation). The mean annual irrigation volume was 27.2% higher for C than IN. Six-year field data and ten-year weather data were analyzed through a soil, plant atmosphere computer model (SPASMO) in order to calculate mechanistically WFP (m3 t-1) as the amount of the annual water consumption (m3) per unit of yield (t). Total water footprint was 46.5% higher for C than IN. The blue component of the water footprint (WFPblue) was the dominant component, accounting for ~70% of the WFPtotal in both treatments. Possible use of WFP analysis within a certification scheme as marketing tool is discussed.