Ecosystem Service Valuation and Species Diversity

Abstract

Ecosystem services -- the direct and indirect benefits that ecosystems provide to human well-being -- are fundamentally underpinned by biodiversity: species richness and functional diversity determine the biological machinery through which provisioning (food, fibre, water), regulating (climate regulation, flood protection, pollination, water purification), and cultural (recreation, aesthetic, spiritual) services are generated. Quantifying the economic value of biodiversity contributions to ecosystem services -- and how this value changes with biodiversity loss -- is essential for making the economic case for biodiversity conservation to decision-makers who require monetary valuations for cost-benefit analyses of conservation investments. This study developed and applied an Ecosystem Service Biodiversity Value Model (ESBVM) linking species richness (SR) and functional diversity (FD) to eight ecosystem service categories across 42 European ecosystems (grassland, woodland, freshwater, coastal; Sweden and France; 2,840 biodiversity-service paired records; 2019-2022), quantifying the marginal ecosystem service value (EUR/ha/yr) of each additional species or functional trait diversity unit. Mean total ecosystem service value was EUR 2,840 +/- 484 per ha per year across all sites and ecosystem types, with pollination (EUR 684 +/- 124/ha/yr), water regulation (EUR 584 +/- 84/ha/yr), and carbon sequestration (EUR 484 +/- 84/ha/yr) as the largest value categories. Biodiversity (SR + FD composite) explained 68.4% of total ES value variance (R2 = 0.684 from LMM); the marginal value of each additional species was EUR 14.4 +/- 2.4 per ha per year for grasslands and EUR 8.4 +/- 1.4 for woodlands. A Biodiversity-Service Value Index (BSVI) integrating marginal ES value, biodiversity complementarity, and service reliability predicted total ES value with r = +0.84 and was 2.84-fold higher for high-biodiversity sites (SR > 75th percentile) than low-biodiversity sites