Mitigating Farmland Biodiversity Loss: A Bio-Economic Model of Land Consolidation and Pesticide Use

TL;DR

This paper develops a bio-economic agent-based model to analyze how land consolidation and pesticide policies impact farmland biodiversity, revealing that combined strategies are most effective in mitigating biodiversity loss.

Contribution

It introduces a novel integrated bio-economic model to evaluate policy impacts on biodiversity, highlighting the importance of combined pesticide reduction and farmer subsidies.

Findings

Pesticide reduction initially boosts biodiversity but may lead to land consolidation and decline.

Subsidizing small farmers stabilizes land use and enhances biodiversity long-term.

Combined policies outperform individual strategies in biodiversity conservation.

Abstract

Biodiversity loss driven by agricultural intensification is a pressing global issue, with significant implications for ecosystem stability and human well-being. Existing policy instruments have so far proven insufficient in halting this decline, which raises the need to explore the possible feedback loops that are pivotal to ecosystem degradation. We design a minimal integrated bio-economic agent-based model to qualitatively explore macro-level biodiversity trends, as influenced by individual farmer behavior within simple decision-making processes. 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.