Environmental parameters monitoring in the oldest show cave of Italy: Bossea Cave

Bossea Cave (Piedmont, Italy) was opened to the pubblic in 1874, making it the first show cave of Italy. This cave develops for about 2800 m in a tectonic contact between carbonate rocks of Middle Triassic, and Permotriassic metavolcanics, and it is crossed for about 1.5 km by a subterranean collector. Three different underground laboratories are present inside the cave to monitor and study several environmental parameters: the Underground Karst Laboratory of Bossea Cave managed by the S.O. Bossea C.A.I. and by the DIATI - Politecnico di Torino, the Karst Hydrogeology Lab, financed by the DIATI – Politecnico di Torino, and the “Giovanni Badino” Climatological Research Centre, funded by PaleoLab of DIATI – Politecnico di Torino and S.O. Bossea C.A.I. The Underground Karst Laboratory of Bossea Cave, together with ARPA Piemonte and ARPA Valle d’Aosta, is mainly concerned with the Radon (222Rn) monitoring. The gas exchange dynamics between water, rock and atmosphere are studied: three Radon monitors for water and two for air tracking were installed in different areas of the cave. The Karst Hydrogeology Lab has 11 data acquisition systems to monitor every 15 minutes water levels, temperature and electrical conductivity of the main subterranean collector and a series of secondary water supplies. The flow rate of the main collector and some secondary inputs are recorded since 1982. The “Giovanni Badino” Climatological Research Centre is aimed at monitoring air, rock and water temperature with extremely precise instruments, calibrated by INRiM. Six main stations are located in touristic and non-touristic cave areas. From June 2021, 52 temperature probes are present in the cavity, acquiring data every 10 minutes. Three atmospheric pressure meters, a pluviograph and two data acquisition systems with four probes for CO2 monitoring are part of the same Lab. Caves are the most important geo-heritage worldwide, however, when cavities are transformed in show caves, an additional impact is produced (e.g. air temperature and CO2 increment, lampenflora growth and pollution). Research allows a greater knowledge of the peculiarities and problems of the system, considering the cave not only a tourist attraction, but an important ecosystem to preserve. Bossea cave is a perfect example of how managers, speleologists and scientists collaboration can exist and bring innovation to natural resources conservation

The Underground Karst Laboratories of Bossea Cave: more than 50 years of collaborations and research

The Bossea Cave, Piedmont, is the first show cave of Italy, opened to the pubblic in 1874. The cavity develops for about 2800 m in the tectonic contact between the Middle Triassic carbonate rocks, and Permotriassic metavolcanics. A main water collector (Mora River) and several water supplies are present inside the cave. Different underground karst laboratories to study hydrogeology, climatology, radon activity and subterranean biology are located in the cave, managed by a multidisciplinary group from Struttura Operativa Bossea C.A.I., DIATI - Politecnico di Torino, and Biologia Sotterranea Piemonte - Gruppo di Ricerca, working together with ARPA Piemonte, ARPA Valle d’Aosta and INRiM. The first laboratory was built in 1969 by volunteers of Gruppo Speleologico Alpi Marittime; over the years, more than 60 sophisticated data logger and sensors were positioned in different touristic and non-touristic areas of the cavity, thanks to the contribution of volunteers, associations and public authorities. The hydrogeological research concerns both the flow hydrodynamics and the water geochemistry. Mora River is continuously monitored since 1983, and water sampling under different hydrodynamic conditions are carried out to chemical analyses. Tracing experiments from surface watercourses to spring waters have been done to understand the recharge area of the karst aquifer. Different environmental parameters are continously monitored in the cave, such as air circulation, air, rock and water temperature, relative humidity, air and water CO2 concentration. Rainfall and snowmelt are monitored too, above and inside the cave, evidencing the infiltration events. Radon (222Rn) derive from the radioactive 238U decay, spreading rapidly into the cave atmosphere and waters. The gas exchange dynamics between rock, water and atmosphere are studied, testing also different equipments for the radon monitoring. Subterranean biology investigations started in 1970, discovering over the years more than 125 different species of hypogeal fauna in the system (75 in the last 30 years), of which four endemics, and six new species to science. A strong contribution to the dissemination of the results was done by the operators, organizing training courses, activities for schools, environmental education, seminars, conferences, and online updates. The fundamental collaboration with the cave managers has allowed to carry out innovative research in this cavity, and to disseminate the discoveries to a not purely scientific or speleological pubblic. Research allows a greater knowledge of the peculiarities and problems of the system, considering the cave not only a tourist attraction, but an important ecosystem to preserve