Anthropogenic disturbances shape functional composition and diversity in Brazilian savanna: Contrasting effects of local and landscape-scale drivers

Abstract

Anthropogenic activities, such as habitat conversion for agriculture and livestock grazing, alter ecosystem structure and biodiversity at both local and landscape scales. In the Cerrado, a global biodiversity hotspot, these pressures drive species loss and functional shifts, making it essential to understand their effects on functional diversity and ecosystem functioning. In this study, we evaluated how local and landscape-scale anthropogenic disturbances influence the functional diversity of Cerrado stricto sensu tree communities. We sampled 12 forest fragments subjected to varying intensities of disturbance and analyzed community-weighted means (CWMs) of key plant attributes and functional diversity indices. Cattle circulation positively influenced wood density, seed width, fruit width, and functional dispersion, leading to increased functional diversity and greater attribute heterogeneity. Habitat loss favoured larger-statured species and earthworm extraction reducing maximum diameter and tree height. Silviculture cover negatively impacted fruit-related attributes and decreased functional evenness, promoting functional homogenization. Our results indicate that anthropogenic disturbances affect the functional composition and diversity of Cerrado stricto sensu in distinct ways: local disturbances primarily influence mechanical resistance and structural attributes, whereas landscape-scale factors mainly affect dispersal-related attributes. Moreover, cattle circulation and habitat loss can promote species turnover, probably favoring forest-associated species in disturbed areas, increasing functional heterogeneity, but potentially compromising the persistence of open-canopy specialists. To mitigate these impacts, conservation strategies should enhance habitat protection and connectivity, support dispersal and gene flow, and incorporate functional attribute-based approaches in conservation and restoration planning.