Groundwork matters: inventory of native and exotic plants of the northwestern patagonian national parks

Background and aims: Inventories in protected areas are essential for planning conservation actions. We aim to: provide a database of the vascular plant species of the National Parks of northwestern Patagonia, Argentina; highlight the singularity of these Parks; and analyze the incidence of exotic species in the protected areas of this region.M&M: We generated a database of the species of Lanin, Nahuel Huapi (including PN Los Arrayanes), Lago Puelo and Los Alerces National Parks. For each species, the following variables were recorded: botanical family, scientific name, common name, native or exotic character for Argentina, habit and environment. The presence of each species was supported by a reference herbarium specimen. The richness and taxonomic composition of native and exotic species, and of native species exclusive to each Park and of exotic species present in all of them were analyzed. Species richness by habit and environment was also determined.Results: A total of 1304 species, subspecies and varieties were recorded, 975 are native to Argentina and 329 are exotics. The percentage of exotic species ranged from 17% (Lanin) to 31% (Lago Puelo).Conclusions: The Parks analyzed have a diverse and unique native flora and their biodiversity can be strongly threatened by the high percentage of exotic plant species. The database generated is a fundamental tool for planning conservation and management policies in these Parks.