Adapting to climate change by improving irrigation practice in Vipava Valley, Slovenia

The DSSI implementation team was set up within the LIFE ViVaCCAdapt project, and is composed of the staff of the University of Ljubljana, the Municipality of Ajdovščina, the Regional development agency ROD Ajdovščina, and the enterprise BO-MO Ltd. The team helped implementing the DSSI together with 35 local farmers, who were, from the very beginning, at the heart of the innovation process.

To increase climate change resilience, the farmers in the Vipava Valley began participating in the LIFE ViVa CCAdapt project in 2016, contributing  to the design of the climate change adaptation strategy and to the ranking of over 40 adaptation measures by assigning priorities.

Over the project lifetime, 35 farmers signed an agreement to participate in the DSSI development process. On-farm soil properties (soil texture, soil-water retention characteristics), and plant phenophases were defined. Next, soil moisture sensors were installed on each farm to measure soil-water content at various depths. Apart from the individual on-field and phone consultations, tailored to the on-farm practice, each farmer was encouraged to ask any question related to DSSI functioning, to freely use the tool and provide continuous feedback on how the DSSI was used in and was changing the everyday irrigation practice. All suggestions were instantly directed into DSSI development and improvement.

Over the six-year process, the farmers started using DSSI gradually. Before entering the project, farmers based their irrigation decisions on their experience and general assumptions. Then, farmers began integrating data from the real-time soil-water monitoring into their decisions. When the DSSI was introduced, farmers slowly started using daily irrigation recommendations. The mid-term evaluation, based on field data and simulations in 2019, showed that if farmers continue to use DSSI, they will achieve a 25% reduction in total irrigation-volume consumption, a 24% reduction in energy requirements, and a 24% reduction in CO₂ emissions (Cvejić et al., 2020). Although the final evaluation from the period 2020-2021 is still underway, the preliminary results indicate some of the farmers exceeded good results from 2019.

Some of the limiting factors that challenge the DSSI implementation and future development include:

• functioning of on-field equipment; their regular maintenance is necessary for a good functioning of the DSSI;
• actual possibility of using water for irrigation: sometimes, the needed water was not available for irrigation due to maintenance of the irrigation systems and related water infrastructure;
• future financing of maintenance, and development of public DSSI.

The total budget of the ViVaCCAdapt project, is EUR 869028. The European Commission contributed 60%, the Ministry of the Environment and Spatial Planning of the Republic of Slovenia 20% of the project's eligible costs. The project partners provided the rest. Of the total value of the project, 147,200 euros are intended for the establishment of DSSI.

The DSSI allows saving water resource in a future looking perspective of increasing temperature and decreasing of precipitation. Other co-benefits of a more efficient irrigation include energy savings, with related benefits in terms of costs and greenhouse gas emissions. The initiative also led to increased awareness of farmers on the topic of climate change. Co-designing and ranking of adaptation measures by involving farmers of Vipava Valley is expected to lead to an increased sense of ownership of the adaptation strategy developed in the project and an increased attention on the use of water resources.