Valuing biodiversity-linked ecosystem services in agricultural landscapes: Systematic review and meta-analytic approach for farm-level decision support

Biodiversity-linked ecosystem services (ES) sustain agricultural productivity, yet their economic valuation remains uneven and fragmented. This study integrates global and regional evidence through a systematic review of farm-level assessments of pollination, natural pest control, and soil biodiversity, complemented by a Europe-focused meta-regression on water purification. Studies linking ecological indicators to monetary outcomes were identified in Scopus and Web of Science. The review followed PRISMA 202 0 guidelines, included 92 studies, and assessed study-level bias narratively. Quantitative syntheses employed robust standard errors with sensitivity analyses. The meta-regression (50 observations) shows that ES values increase with GDP per capita but decline with organic land share, average farm size, and publication year, while population density has no significant effect. Model fit is satisfactory (adjusted R² ≈ 0.37), and results are robust across
specifications. Methodological patterns reveal that production-function approaches dominate for market linked services, whereas cost-based and stated-preference methods prevail for public-good services. Findings highlight that incorporating socioeconomic covariates enhances the reliability of benefit transfer and supports cost-effective targeting of agri-environmental measures. At the farm level, biodiversity supportive practices yield both private and public benefits, creating opportunities for co-investment. At the policy level, integrating service-specific ecological indicators into the Common Agricultural Policy (CAP) framework could improve its efficiency and ecological impact.