Local and landscape‐scale effects of an ant nest construction in an open dry forest of Uruguay

1. Ants modify soil properties via nest construction and by doing this modulate soil resources for other organisms. In this sense ants are recognised as ecosystem engineers. 2. In this framework, two less well‐studied issues are focused on: (i) the permanence of the effects of ant nests on plant communities after colonies have died, and (ii) the scaling up from patch to landscape‐scale effects. 3. The aim of the present study was to address these issues in the open dry forests of Uruguay, inhabited by the ant Atta vollenweideri Forel. The active and abandoned nests of this ant represent different and conspicuous patches (30–60 m²) in the landscape. 4. The soil concentration of sodium, a key element in the system, was substantially higher among active nests, and remains high during the early stages of abandoned nests. Woody species abundance, richness, and composition were affected at the patch scale, and simulation models suggested an increase in species richness at the landscape scale. 5. The present study highlights the importance of abandoned nests for plant‐species richness in the ecosystem engineer framework and the need to advance in an integrative approach to study both local and landscape effects of ant's nests.