Assessing forest restoration effectiveness in the Seasonal Semideciduous Forest in the Upper Paraná Atlantic Forest ecoregion using epigaeic ant assemblages

Abstract Itaipu Hydroelectric Power Plant initiated a large reforestation programme after the expropriation of the areas destined for the formation of the reservoir. This study aimed to evaluate the effectiveness of forest restoration of the Seasonal Semideciduous Forest in the Upper Paraná Atlantic Forest ecoregion, Brazil, using epigaeic ant assemblages as bioindicators, by comparing ant species richness and composition in the Reservoir Protection Strip with adjacent areas, such as the primary forest of the Iguaçu National Park and the Permanent Preservation Area located on a rural property and agricultural areas. In total, 171 ant species were identified. Ant species richness was higher in forest than in agricultural areas and did not differ among forest areas. However, ant species composition in forest areas, regardless of the restoration technique used, was not similar to the primary forest, possibly due to variation in forest recovery time. This study highlights the great value of the Iguaçu National Park as a conservation unit. Also, it reveals that the efforts for the creation and maintenance of the Reservoir Protection Strip, which remains without anthropic interventions for years, might indeed lead to a complete recovery of the ant species composition over time, reinforcing their great importance for biodiversity conservation.