Effectiveness of Protected Areas in the conservation of <em>Nothofagus antarctica</em> Forests in Santa Cruz, Argentina

Protected areas (PA) constitute a fundamental strategy for mitigating biodiversity loss. Land-sparing approach has expanded in response to international agreements, but expansion of PA does not guarantee conservation objectives. The objective was to assess PA effectiveness in conserving Nothofagus antarctica forests in Santa Cruz (Argentina) evaluating human impacts (fire, animal use, harvesting). The research was conducted within pure native forests in Santa Cruz, Argentina. This province encompasses 52 protected areas, representing the highest concentration of conservation units within the forested landscapes of the country. At least eight of these areas include N. antarctica forests. Three land tenure categories were evaluated: protected areas (PA), buffer of 15-km from PA boundaries on private lands (BL), and private lands (PL). 103 sampling plots were established, where 38 variables were assessed (impacts, soil, forest structure, understory, animal use). Three indices were developed to analyze ecosystem integrity: forest structure (FI), soil (SI), and animal use (AI). PA presents highest FI (0.64 for PA, 0.44 for BL, 0.30 for PL) and AI (0.60 for PA, 0.55 for BL, 0.52 for PL), and together with buffer zones, the highest SI (0.43 for PA, 0.47 for BL, 0.32 for PL. PA showed superior integrity regarding compared to BL and PL, indicating effective preservation despite anthropogenic impacts.