Long term financial assessment of regulated deficit irrigation scheduling in super highdensity olive orchards

Abstract

The financial feasibility of using leaf turgor pressure (TP) and crop coefficient (CC) based irrigation scheduling in an ‘Arbequina’ super high density olive orchard under regulated deficit irrigation (RDI) has been evaluated and compared to fully irrigated trees (FI).The experiment was conducted in a commercial orchard near Seville (Spain). A 6-year dataset, covering the transition from young trees to fully productive trees, has been used. Two RDI treatments, providing 30 and 60% of the crop water needs, were used in the transition period (2010-2012),while in the fully productive period (2013-2015) two RDI treatmentswere scheduled providing 45% of the crop water needs, of which one used TP related measurements (30-45RDITP; 60-45RDITP) while the other used the CC approach (30-45RDICC; 30-45RDICC) to schedule irrigation. The Discounted Cash Flow Analysis for the entire life of the orchard provided economic indicators that demonstrated that both, 30-45RDI and 60-45RDI strategies guaranteed the profitability of SHD olive orchards in the long-term showing positive Net Present Value and Internal Rate of Return above the interest on capital. All the financial indicators suggested higher financial performance of RDITP as compared to RDICC, but differences between the RDI strategies used in the transition period were not significant. Finally, the FI treatment showed the most profitable indicators suggesting that RDI would be justified for high water prices or reduced water irrigation allotments