  Biodiversity loss driven by agricultural intensification is a pressing global
issue, with significant implications for ecosystem stability and human
well-being. We design an integrated bio-economic agent-based model, informed by
historical data from the French agricultural sector, to project future
biodiversity trends and evaluate policy interventions. Our model predicts
further biodiversity decline under a business-as-usual scenario, primarily due
to intensified land consolidation. We evaluate two policy options: reducing
pesticide use and subsidizing small farmers. While pesticide reduction rapidly
benefits biodiversity in the beginning, it eventually leads to increased land
consolidation and further biodiversity loss. In contrast, subsidizing small
farmers by reallocating a small fraction of existing subsidies, stabilizes farm
sizes and enhances biodiversity in the long run. The most effective strategy
results from combining both policies, leveraging pesticide reduction alongside
targeted subsidies to balance economic pressures and consistently improve
biodiversity.
