## 6 Conclusions: Effective Implementation of Corrective Measures  
The possibility of incorporating the results of environmental monitoring in caves into a comprehensive management model, which also takes socioeconomic aspects into account, is the main interest of this type of research for managers of show caves. Such monitoring will also allow for the adjustment of initial carrying capacity thresholds as \begin{table}
\begin{tabular}{c c c c c c c} \hline \multirow{2}{*}{**Cave**} & \multicolumn{2}{c}{**Monthly**} & \multirow{2}{*}{**Microclimate Impacts**} & \multicolumn{2}{c}{**Maximum**} & \multirow{2}{*}{**Microclimate Impacts**} \\  & **Average** & & & & **Threshold** & \\ \cline{2-2} \cline{5-7}  & **Visitors/Day** & \(\Delta\)**T (°C)** & \(\Delta\)**CO\({}_{2}\) (ppm)** & **Visitors/Day** & \(\Delta\)**T (°C)** & \(\Delta\)**CO\({}_{2}\) (ppm)** \\ \hline El Castillo & \(\leq\)60 & \(\leq\)0.10 & \(\leq\)110 & 130 & \(\leq\)0.16 & \(\leq\)180 \\ \hline Covalanas & \(\leq\)15 & \(\leq\)0.11 & \(\leq\)220 & 25 & \(\leq\)0.15 & \(\leq\)350 \\ \hline \end{tabular}
\end{table} 
Table 3: Recommended daily rate of visitors in terms of monthly average values and maximum thresholds and expected increases generated in the temperature and CO\({}_{2}\) concentration of cave air. The expected microclimate impacts are defined by the upper level of the interquartile range of variation for each parameter, generated by both the monthly averages and the maximum thresholds of daily visitors. a function of changes in consumption patterns, local realities, and the identification of unanticipated but unacceptable environmental impacts [40]. The tourism stakeholders and cave conservation technicians from the autonomous government of Cantabria have carried out a progressive adaptation in the tourism management of these caves until they are fully adapted to the environmental sustainability defined in this study. The new visiting regime maintains the opening of the two caves from Tuesday to Sunday and reduces the number of daily accesses to the caves and the number of visitors in each of them through two phases, namely a transitory one from 10 May 2024 until 15 September 2024 and a definitive one from this last date. The El Castillo cave went from receiving 1236 visitors per week to 780 during this transitory phase, through 10 passes per day with a maximum of 13 people per visit. With the definitive regime, the El Castillo cave can be visited by a maximum of 384 people per week, with eight passes and a maximum of eight visitors per pass (including the cave guide). In the Covalanas cave, these visits rates were adjusted from 102 visits per week to 90, both in the transition period and in the definitive period, through three visits per day of five people each (including the cave guide). In any case, this proposal of recommended daily visit limits for each cave is preliminary in nature, and there is an ongoing continuous environmental monitoring after it was fully implemented to assess its suitability and effectiveness in the medium and long term. Conceptualization, A.F.-C. and S.S.-M.; methodology, A.F.-C. and S.S.-M.; validation A.F.-C., S.S.-M., and S.C.; formal analysis, A.F.-C. and S.S.-M.; investigation, A.F.-C., E.P.-P., T.M.-P., S.C., R.O., J.L., and S.S.-M.; resources, E.P.-P. and R.O. ; data curation, A.F.-C.; writing--original draft preparation, A.F.-C., S.S.-M., and J.L. ; writing--review and editing, A.F.-C., S.S.-M., and J.L. ; visualisation, A.F.-C. and J.L. ; supervision, A.F.-C.; project administration, A.F.-C. and S.S.-M.; funding acquisition, A.F.-C. and S.S.-M. All authors have read and agreed to the published version of the manuscript. This research was funded by the \"Consejeria de Universidades, Igualdad, Cultura y Deporte del Gobierno de Cantabria\" and the Spanish Ministry of Science, Innovation through project PID2023-146299 OB-C21. This is a contribution from CSIC Interdisciplinary Thematic Platform Open Heritage: Research and Society (PTI-PAIS). Not applicable.