Geoheritage and global changes: insights on the open issues of geoconservation

Over the last 30 years, the field of studies related to geological heritage and geodiversity has gained some interest within the scientific community, in parallel with a renewed awareness among scientists, stakeholders and the public of the importance of preserving geological assets. Numerous works have been devoted to the development of appropriate procedures for geo-conservation (e.g. Crofts, 2020), and geoconservation is envisaged, albeit in different forms, in two frameworks of UNESCO sites - World Heritage Sites and Global Geoparks. The generic geoconservation process appears to be fairly well established in the literature and essentially consists of: i) identification and assessment of sites of geological interest to be conserved (the geosites); ii) definition of management objectives; iii) assessment of threats and degradation risk; iv) management zoning and implementation of conservation measures; v) monitoring; vi) review of the conservation strategy. However, although the general procedure is well defined, there are still several methodological gaps in relation to individual steps. The most important of these is the assessment of degradation risk, for which many proposals have been made in the literature, but there is no consensus on which is the most appropriate and effective. Furthermore, many of the proposed methodologies do not take into account the specificities of different types of geosites. This thesis therefore aims to address some of the open issues of the geoconservation process, with the proposal of specific methodologies that can be used for the definition of geoheritage management strategies. In particular, this work had the following objectives: (i) To propose and test a quantitative methodology for assessing the risk of degradation of geosites. The proposed methodology is based on the concepts of fragility and vulnerability as defined by \textcite{garcia-ortiz_concepts_2014}. The quantification of fragility, natural vulnerability, anthropogenic vulnerability and protection measures is proposed through a set of indicators to which numerical values are assigned. The numerical indicators have been chosen so that the methodology is replicable for any type of geosite inventory, while taking into account the specificities of individual geosite categories (e.g. geomorphosites). (ii) To propose and test a semi-quantitative methodology for rapid assessment of climate change sensitivity of geosites. (iii) To propose and test a methodology for the proper management zoning of sites of geomorphological interest (geomorphosites), with the definition of buffer zones around the actual geosite area, taking into account any active processes interacting with it. The three proposed methods were tested on two inventories of geosites belonging to two different study areas: Liguria (Italy) and the Hérens Valley (Valais, Switzerland). With regard to Liguria, the geosite inventory was taken from previous works (Ferrando et al., 2021); it contains 120 geosites of different types and primary interest. For the Hérens Valley, on the other hand, a new inventory, including 44 geosites, had to be made as a preliminary step. The geosites included in this inventory were then evaluated according to the procedure proposed by Reynard et al. (2016), before applying the three methodologies mentioned above. Based on the results obtained, specific management actions were then proposed to reduce the risk of degradation of the most fragile and vulnerable geosites. Finally, some open questions regarding the conservation of active geomorphosites were discussed. The results obtained in this thesis thus provide further insights into the procedures and management measures to be taken for effective geoconservation. Furthermore, they show how, especially in the case of geomorphosites, geoconservation actions can be more effective with a systemic approach.