Area characterisation:
- Carnuntum covers approximately 900 hectares of vineyards with an average farm size of 6.2 hectares, larger than Spanish counterparts. The region features loess soils on plains and gravel on slopes.
- Climate conditions bring potential for increased water erosion intensity due to climate change projections.
- The production model assumes moderate slopes with trellis systems and no irrigation. Winegrowers benefit from higher grape prices (€0.90 per kilogram) through direct marketing and own wine production, generating added value compared to cooperative-sold grapes.
Objective:
To compare the profitability and cost-effectiveness of three soil management scenarios (conventional tillage, temporary cover crops, permanent cover crops) in Carnuntum vineyards, incorporating both private on-site erosion costs borne by farmers and social off-site costs borne by society, to inform policy decisions about agri-environmental subsidies for erosion control.
Context:
Challenges addressed
The measure addresses environmental management of soil erosion and the related loss of soil and ecosystem services.
Financing:
Costs of NbS
Across about 900 ha of vineyards in Carnuntum, switching from conventional tillage to permanent cover crops raises management costs by about EUR 207 per ha per year (2023 prices).
Potential impacts/benefits:
Soil loss falls from about 9.7 t/ha a year under tillage to 1.4 t/ha with permanent cover crops, conserving nutrients, organic matter and water and limiting sediment damage beyond the vineyard. Avoided on-site and off-site erosion damage is worth about EUR 529 per ha per year (2023 prices), of which only about a quarter accrues to the grower. Cultural and aesthetic benefits of greener vineyards were not valued and would add further to the gains.
Benefit–cost ratio
This gives a BCR of 2.56. As in Spain, cover crops are cost-effective for society, while private erosion savings fall short of the extra cost to growers.
Actions:
- Field surveys conducted across sixteen vineyards (eight for each of the two most common soil management techniques) to collect topographic, soil, cover and management information.
- Daily climate data for 16 years (2000-2015) obtained from nearby weather stations.
- The ORUSCAL tool calibrated using strategy incorporating soil moisture subfactor to assess erosion risk under different management scenarios.
- Policy Analysis Matrix constructed using gross margin calculator data and farm budgets adjusted for inflation to 2016 values, incorporating subsidies, input-output prices and monetised erosion costs.
- Sensitivity analysis conducted on output prices, labour costs, variable machinery costs and erosion costs.
Contacts:
Study overview:
Carnuntum is a small Protected Designation of Origin wine region in Eastern Austria, located near the capital Vienna. With approximately 900 hectares under vine and about 150 winegrowers, the region produces 43,000 hectolitres of wine annually, roughly half white and half red. Unlike many Mediterranean wine regions, Carnuntum shows a clear tendency towards cover crop usage, though bare soil management is still observed.
The region is characterised by a Pannonian climate with cold winters and dry, warm summers, averaging 11.1°C annually with 636 mm of precipitation. Predominant soil types include loess and gravel on slopes. Due to touristic attractiveness and proximity to Vienna, the region is oriented towards direct marketing, with many winegrowers producing their own wine and generating added value through bottling and branding. This contrasts with regions where grapes are sold to cooperatives.
Research conducted through the VineDivers project evaluated soil management scenarios using the ORUSCAL erosion model and Policy Analysis Matrix, comparing conventional tillage (bare soil), temporary cover crops in alternating inter-rows with tillage in other rows, and permanent cover crops in every inter-row throughout the year. The study incorporated private on-site costs borne by farmers and social off-site costs including infrastructure damage and environmental degradation.