Evaluating irrigation strategies for potato production at a sub-humid site under current conditions and future climate scenarios

Climate change is already having an impact on agricultural production even in sub-humid regions such as parts of Austria that have not yet been confronted with the problem of limited water availability. Moreover, conditions are set to worsen in the future. In order to meet the expected increased irrigation demand in particular regions and conserve water resources in accordance with the EU Water Framework Directive, water resources for crop production should be managed with foresight and the focus should be on efficient irrigation strategies. This approach is in line with broader efforts to adapt agricultural systems to evolving environmental challenges.

The aim of this study is to assess the impact of irrigation strategies on potato production in north-eastern Austria as well as future developments under the given local conditions. The potato is important for food security both regionally and globally. Potatoes were grown for the study in 2023 and 2024. The trials were set up as a block system in larger plots with a row/dam spacing of 0.75 m and a length of around 150 m. The variants were irrigated with different irrigation systems: drip lines on the dams, sprinklers on a pipe system, and a hose reel with irrigation boom. The potato yield and the irrigation water applied were measured. The actual irrigation strategies as well as future conditions were simulated and evaluated using the FAO AquaCrop crop growth model. The simulations utilized local meteorological data sets from a nearby weather station and future climate scenarios based on RCP 4.5 projections.

In general, the yield differences between the two study years were greater than between the irrigation variants. Drip irrigation resulted in the largest crop water productivity, but the absolute yields showed a more differentiated picture. The evaluation of observed and simulated data from 2023 showed that sprinkler irrigation delivered better production results, while drip irrigation had the lowest yield. In 2024, the drip-irrigated variant produced the largest yields. On average, the boom irrigation was performing best. The AquaCrop simulations reflect a similar picture. In addition, simulated irrigation strategies show how sufficient potato yields are possible with limited water availability. In this respect, more specific irrigation strategies that better incorporate the actual environmental conditions are needed. The climate scenario simulated with AquaCrop for the given site shows future yields and the corresponding water requirements. The results could serve as a basis for adapting local irrigation strategies to changing climatic conditions in order to enable sustainable potato production north-eastern Austria.