Global warming makes orcharding difficult in traditional regions

Together with the University of Natural Resources and Life Sciences, ARGE Streuobst and Ingenieurbüro Holler, ARCHE NOAH has analyzed the future of Austrian orcharding in the project "Perspectives for orcharding in a changing climate" . The results show that changing environmental conditions call into question the continuation of our current (scattered) fruit cultivation. It is possible that the Alpine region could be a future cultivation area.

"In previously favorable locations such as the Styrian apple region or the Lower Austrian Mostviertel, the situation for fruit growing will continue to worsen," predicts Bernd Kajtna, fruit expert and agricultural scientist at ARCHE NOAH, the Society for the Conservation and Propagation of Crop Diversity in Schiltern, Lower Austria.

Climate data for three Austrian model regions were analyzed according to their effects: for the Lower Austrian region of Amstetten Süd (Mostviertel), for the Pöllauer Tal Nature Park on the border to the eastern Styrian dessert fruit region and for the Lungau as an inner-Alpine Salzburg high valley, where fruit cultivation is currently hardly relevant.

Orchard meadows and fruit trees are of enormous importance in the Amstetten-Süd small region. Around 140,000 trees provide around 14,000 tons of harvest. In Styria, dessert apples and pears are produced on 6,000 hectares. In addition, there are over 8,000 hectares of orchards in the province, especially in the Pöllauer Tal Nature Park.

The current study includes climate data for the periods 1961-1990 and 1991-2020 as well as scenarios for an average global warming of +2°C and +3°C respectively.

It turns out: "The number of days with late frosts in spring will decrease. But the risk of frost damage may still increase due to the expected earlier start of vegetation. In summer, the main problem will be the lack of water availability," says Kajtna.

In the Amstetten region, for example, orchards and fruit plantations in the so-called "molasse zone" with its gravel subsoil will have to contend with drought. Lower-lying areas in particular will suffer from summer heat and drought stress. The climate favorable for fruit growing is shifting to much higher altitudes. However, regions that were previously only suitable to a limited extent are likely to benefit, provided the warming remains limited to below +2°C.

Orchards in Austria have been in decline for decades, from around 35 million trees in 1930 to around 4.2 million in 2020. According to a German study, over 5,000 species of animals, plants and fungi live in orchards. They provide numerous important services for humans: Pollination, hay, wood, drinking water and flood protection or improvement of the local microclimate. The study presented today comes to the conclusion that these services are worth over 16,000Ꞓ per hectare per year.

In order to be able to deal with the challenges ahead, the existing potential of fruit species, rootstocks and varieties must be viewed, utilized and adapted to the needs of today. Then fruit can remain an important part of regional agriculture and a carrier of ecological diversity in the future.

"For the future of our fruit cultivation, the focus must be on active climate protection in order to limit global warming to below +2°C. If this goal is achieved, there will also be a future for fruit growing in Austria," says Bernd Kajtna from ARCHE NOAH.