Configurational Fragility of Forest Landscapes Under Multiple Anthropic Uses.

The conversion of native vegetation to anthropogenic land uses and landscape fragmentation are primary drivers of biodiversity loss and ecosystem services decline in tropical watersheds. Understanding how land use shapes the spatial configuration of forest fragments is essential to inform conservation and restoration strategies. We evaluated the configurational fragility of forest remains in the Lower São Francisco River Watershed, Brazil, combining structural metrics (area, core area and shape index) with land use and land cover (LULC). Fragility levels were defined through hierarchical classification and their relationship with LULC was tested using distance-based redundancy analysis (db-RDA). A principal component analysis (PCA) first summarized LULC variation. The watershed is dominated by anthropogenic matrices, with agriculture and pasture occupying 66.9% of the area, mainly pasture (57.7%). This resulted in 37,022 highly reduced and discontinuous forest fragments, of which 72.2% exhibited high configurational fragility. Savanna formation, the most representative native vegetation, had 96.1% of its patches within intermediate to high fragility levels. The PCA revealed three dominant gradients: herbaceous formations, wooded sandbank vegetation and wetlands (PC1), contrast between savanna formations and pasture (PC2), and heterogeneity of forests, forest plantation and mosaic of uses (PC3). db-RDA confirmed this pattern (adjusted