Environmental gains and economic costs of perennial crops: A spatially explicit assessment for Baden-Württemberg

Résumé fourni par la source

: Agricultural systems face the increasing challenge of balancing societal objectives, including food production, energy supply, and environmental and biodiversity conservation. Perennial biomass crops such as Miscanthus × giganteus ( Miscanthus ) and Silphium perfoliatum ( Silphium ) could contribute to the achievement of ecological and biodiversity objectives, however their implementation in Germany is still scarce. This study therefore assesses whether Miscanthus and Silphium can contribute to improved environmental performance in Baden-Württemberg (BW), Germany, and quantifies associated economic trade-offs. We apply PALUD EVAL , a regional land-use optimization model operating at NUTS-3 level, which integrates economic decision-making with an extensive ecological assessment including indicators for soil erosion, nitrate leaching, particulate phosphorous (PP) losses, greenhouse gas (GHG) emissions and biodiversity. In scenarios requiring a 20% reduction in erosion, nitrate leaching, PP and GHG emissions, and a 20% increase in BW’s average biodiversity – potential – index (BPI), results show that Silphium provides the strongest biodiversity improvements, while Miscanthus yields the highest reductions in nitrate leaching and GHG emissions. However, across most scenarios, flowering fallow (FF) emerges as the dominant, more cost-effective measure, reaching up to ∼34,100 ha compared to ∼22,700 ha for Miscanthus , ∼19,500 for Silphium in the Multi-Target scenario, thereby limiting the expansion of Miscanthus and Silphium under current economic conditions. Reducing risk-related cost premiums by 50% more than doubles the Miscanthus area to ∼51,600 ha in this scenario, while Silphium increases moderately to ∼22,600 ha. Compliance with environmental targets leads to notable economic impacts: Regional gross margins decline by up to 26% in the Multi-Target scenario, while public expenditure increases substantially. Spatial allocation patterns suggest that Miscanthus is primarily suited to northern BW, whereas Silphium is favored in regions with established biogas capacity. Overall, PALUD EVAL highlights the conditional potential of Miscanthus and Silphium to support environmental policy goals when appropriately targeted and incentivized.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.