Conservation Prioritization Using Multi-Criteria Analysis

Abstract

Systematic conservation planning requires transparent, repeatable methods for allocating limited management resources across landscapes that simultaneously support biodiversity, provide ecosystem services, and sustain human livelihoods. This study developed and applied a multi-criteria analysis (MCA) framework integrating six criteria -- species richness, threatened species density, habitat connectivity, ecosystem service value, restoration feasibility, and management cost - to rank 1,840 planning units (5 km x 5 km) across the Central Mediterranean biodiversity hotspot region spanning southern Italy, Sicily, Sardinia, and Malta. Criterion weights were derived by Analytic Hierarchy Process (AHP) from structured expert elicitation with 48 conservation practitioners and scientists. Spatial prioritisation was additionally conducted in Zonation v4 and Marxan with Zones for comparison with the AHP-MCA output. The three methods showed high rank-order agreement (Spearman rs = 0.74-0.82 between method pairs). The top 20% of planning units by MCA score contained 68.4% of threatened vertebrate records, 72.8% of endemic plant species, and 58.4% of assessed high-value ecosystem service areas, at an estimated management cost of EUR 284 million annually. Gap analysis revealed that only 38.4% of the top-priority planning units are currently within the Natura 2000 protected area network, identifying 184,200 ha of high-priority unprotected habitat. Scenario analysis demonstrated that weighting ecosystem services equally with biodiversity increased protected area cost-efficiency by 24.8% while retaining 91.2% of threatened species representation, providing a quantitative basis for integrated biodiversity-ecosystem service conservation planning under the EU Nature Restoration Law.