Optimal crop rotation benefits agroecosystem water-use efficiency across Europe

Climate change is intensifying water scarcity across Europe, raising urgent questions about how to improve the water-use efficiency (WUE) and ecological resilience of agricultural systems. Crop rotation—an essential form of agroecosystem biodiversity—has long been recognized as a cornerstone of sustainable land management, yet its large-scale contributions to improving WUE remain poorly quantified. Here, we integrate multi-year remote sensing observations with a Europe-wide crop rotation dataset to assess how rotational biodiversity influences agroecosystem WUE at 300m resolution across Europe. By leveraging multi-source satellite data and causal explainable machine learning, we show that greater rotational diversity substantially enhances WUE relative to monoculture systems, with the strongest improvements emerging in water-limited environments of Southern and Eastern Europe. Biodiversity in crop sequences increased WUE primarily by boosting gross primary productivity while stabilizing evapotranspiration under highly variable climatic conditions. Regions practicing cereal–legume/oilseed crop rotations exhibited the largest gains, highlighting the role of nitrogen-fixing and break crops in strengthening ecosystem water–carbon coupling and promoting functional diversity. Moreover, climate anomalies amplified the benefits of biodiverse rotations: during drought years, fields with high rotational diversity maintained significantly greater WUE resilience than continuous cropping systems. Our findings provide the first continental-scale evidence that agroecosystem biodiversity, expressed through crop rotational diversity, is a powerful and climate-robust strategy for enhancing agricultural water-use efficiency. As Europe faces escalating hydroclimatic extremes, promoting biodiversity-driven crop rotations represents a critical pathway toward sustainable, resource-efficient, and climate-resilient agroecosystems.

Keywords: Crop rotations; Biodiversity; Climate change; Agroecosystems; Water-use efficiency; Europe