IrriGrass was implemented at the HBLFA Raumberg-Gumpenstein as an extension of and in combination with the ClimGrass experimental facility. The following factors played a role:
- Irrigation: Different quantities and intervals to determine the optimal water supply
- Plant stands: Comparison of two mixtures – one conventional (yield-optimized) and one drought-resistant
- Data collection: Collection and evaluation of yield parameters (dry matter yield, crude protein yield), soil moisture, evaporation and climatic water balance
- Drought: Controlling precipitation levels through artificial irrigation while preventing natural rainfall through rain roofs for a differentiated analysis of water stress responses
The following findings were obtained during the project:
- Yield: Targeted irrigation significantly reduced yield losses due to drought stress. Depending on the irrigation strategy, both dry matter yield and crude protein yield were higher than in non-irrigated control plots.
- Plant responses: A more drought-resistant plant community showed better adaptation strategies under water scarcity than a community of species adapted to favorable locations.
- Climatic effects: The combination of higher temperatures and increased CO₂ concentration led to altered water requirements.
- Irrigation management: To ensure the sustainable use of water resources, a needs-based, efficient irrigation strategy is required.
The results show that optimized irrigation can be an important adaptation strategy to climate change. It enables more stable yields and can prevent crop failures during dry periods. At the same time, irrigation should be combined with the selection of drought-tolerant plant species and varieties to ensure resource-efficient and sustainable grassland management
