Integrated UAV-based Photogrammetry and Remote Sensing Workflow for Landscape Heritage Mapping and Climate Change Adaptation: A Preliminary Study in the Piedmont Alps (Italy)

Within the European Landscape Convention, landscape heritage emerges from the continuous interaction between humans and nature (European Landscape Convention, 2000), a dynamic relationship that makes it particularly vulnerable to changes, whether due to abandonment or anthropogenic climate change (ICOMOS, 2005). This is especially true in mountain areas, which, according to the Intergovernmental Panel on Climate Change (IPCC, 2022), are among the ecosystems most affected by climate change, with both direct and indirect impacts also on cultural heritage. Regions such as Alps face the risk of losing intangible values like cultural identity, collective memory and the landscape features themselves (IPCC et al., 2022). In line with the 2030 Agenda’s Goal 11.4 (United Nations, 2015), preserving this heritage is an urgent task, particularly for “ordinary” assets: minor, often undocumented elements, preserved mainly through oral sources. Geoinformatics technologies - including UAV-based photogrammetry, remote sensing, and GIS - offer scalable and non-invasive solutions to address these challenges. These tools support detailed documentation and analysis, enable multi-source data integration and contribute to the safeguarding of cultural heritage and related sustainability goals (Xiao et al., 2018). This is exemplified by the methodology proposed for the case of the historic hydraulic and agro-pastoral systems of artificial channels and basins, in a remote alpine valley in Piedmont, Italy. Once vital for water management and seasonal agricultural and pastoralism, these systems are now largely forgotten and only partially recorded in historical registries. Recent water shortages and changes in mountain hydrology have renewed interest in their potential functional recovery. In this context, geoinformatics technologies provide new opportunities for localisation, documentation, and risk assessment. The research test an integrated and non-invasive workflow for mapping these assets, characterised by small-scale geometric features (channels <1 m wide; basins 2-10 m in diameter). Such dimensions make low-resolution regional datasets inadequate, requiring high-resolution, purpose-acquired data. Moreover, long-term abandonment has rendered many features unrecognisable, even to trained observers, without local knowledge or awareness of their historical forms. To address this, the methodology combines UAV-based optical photogrammetry and remote sensing (multispectral, thermal) and spatial analysis within GIS environment. A preliminary phase involved the acquisition and processing of optical, multispectral, and thermal imagery - to generate orthophotos and a DSM - over a test area, where two channels and four basins were known through oral sources. Georeferenced data were analysed in GIS: micro-topography was assessed through DSM analysis; spectral and thermal anomalies were identified through spectral index maps and temperature variation analyses, based on the orthophotos. The data were then combined and synthetised to: a) validate the methodology and locate the assets; b) extract potential recurring features that could serve for detecting similar elements in other areas. Next steps will include a second data acquisition campaign and possible integration of UAV-based LiDAR, to detect features hidden by vegetation. Furthermore, given the growing availability and proven effectiveness of machine learning and deep learning image processing techniques in the ongoing research context, further efforts will focus on investigating their application to improve the detection of recurring patterns within the processed datasets. Ultimately, the aim is to develop a scalable and transferable approach to support the rediscovery and potential reactivation of these widespread yet forgotten heritage systems, which mapping and documentation may contribute to the definition of climate adaptation strategies (e.g. water storage, pastoral supply), considering also traditional landscape management practices.