Tolerància de la fauna cavernícola terrestre de la Cova de sa Font (Sa Dragonera, Illes Balears) envers altes concentracions de diòxid de carboni

[eng] Terrestrial cave-fauna is likely affected by the high concentrations of CO2 found in many cave habitats, typically over
10,000 ppm. Cova de sa Font is a rather simple descending anchihaline cave (25 m deep), that stands out for its extreme CO2
fluctuations throughout the year: from less than 800 ppm in the winter to values exceeding 60,000 ppm in the summer. This
small cavern is actively ventilated during the cold season, but when ventilation ceases in the spring it starts to be invaded
by CO2-enriched “ground air” coming from the surrounding vadose crevices. On the other hand, air composition (radon,
CO2, water vapor) characterizing the whole vadose zone and the seasonal changes observed in cave-atmospheres are obvious
ecological constraints for troglofauna. In order to assess the effects of rising carbon dioxide content on the terrestrial fauna of
Cova de sa Font, a threefold sampling of troglobitic and troglophilic fauna was carried out, using baited pit-fall traps, from
December 2018 to October 2019. We describe the most noteworthy changes in the spatial distribution of several species
and we indicate a strong correlation with confined-air descriptors. Our results suggest that these arthropods have adaptive
abilities to live in such CO2-rich environment