Zoning effects on the community structure of freshwater benthic macroinvertebrates in a Mediterranean National Park (Central Apennine)

Freshwater macroinvertebrates are a fundamental component of the world's biodiversity, which is globally declining, yet they remain largely overlooked in area-based conservation and restoration efforts. Notably, the effectiveness of zoning within protected areas, a prominent tool for balancing nature protection and human activities, is still substantially unexplored in the context of freshwater biodiversity conservation. In this study, we assessed for the first time the influence of zonation on water chemistry, environmental variables, and patterns of freshwater macroinvertebrate diversity across a long-established protected area in Central Italy. We observed no significant differences among zones in terms of water parameters and canopy cover, and no spatial correspondence between areas with higher biodiversity levels and integral protection zones (IRs). However, the IR has a positive effect in restoring macroinvertebrate diversity downstream of human disturbance. Indeed, taxonomic richness decreased (⁓41%) downstream of human settlements, then increased (⁓46%) downstream of the IR located just beyond the urban areas. Our research emphasises that current zoning schemes within protected areas might completely overlook spatial patterns of variation in freshwater biodiversity. Yet, importantly, they also suggest that zoning schemes in terrestrial protected areas should adopt a strategic IR design, integrating species and habitat conservation targets with the exploitation of river autodepuration processes.