Stress-tolerant ants and the impact of quarries on an ant community in Patagonia

Aggregate extraction is an activity that has increased considerably in recent years in Patagonia, providing raw material for road paving and construction industry. This activity deeply impacts soil composition and the biota. Ants are among the most important inhabitants of soils, and are useful indicators of the impact of human activities on ecosystems. This study determines the effect of aggregate extraction activities on a community of ants in a semiarid area of Argentinean Patagonia. In two abandoned quarries, disturbed and nearby control areas were delimited; ants were sampled using pitfall traps and different environmental variables were measured. Our analysis show that many environmental variables were altered in disturbed sites, with a reduction in vegetation cover, modification of percentage of fine grain and soil humidity, and an increase in soil pH and temperature. Thirteen ant species were identified. The Opportunists predominated in disturbed sites, in particular the species Dotymyrtnex tener. The results reveal for the first time the behaviour of the ant community of this semiarid region in the face of a disturbance that directly impacts the soil. The focus on stress-tolerant species for restoration purposes deserves further study.