Linking Environmental Archaeology to Geoheritage: a multifaceted approach to unravel and promote past fluvial landscapes.

Landscapes are geographic areas perceived by people whose characteristics are the result of the interaction between natural factors and human activities. This definition has been established during the European Landscape Convention (Florence, Italy - October 20th, 2000) when the member States of the Council of Europe debated and proposed guidelines to achieve sustainable landscape development based on a balanced and harmonious relationship between social needs, economic activity and the environment. The landscape has an important public interest role in the cultural, ecological, environmental and social fields, and constitutes a resource favourable to economic activity.
Multi-temporal analysis of landscapes enables the understanding of how geomorphic constraints conditioned the human settlements in the past and how land-use altered the environment natural development. Moreover, the diachronic approach to landscape research helps in evaluating the grade of sustainability of past societies systems and their impact on natural resources throughout the Anthropocene.
This 3-year Ph.D. project aimed to understand past landscape evolution and in identifying the features derived by the human-environment interplay to promote the conservation of those features through geoheritage plans. To perform the project’s objectives a multi-disciplinary approach that combines Environmental Archaeology methodologies and Geoheritage tools in GIS has been applied. Case studies in fluvial environments have been selected to test the interdisciplinary approach proposed because floodplains represented the most suitable environment for human sustenance in history. The main area considered in this Ph.D. project concerns the evolution of Central Po Plain (Italy) during the Middle Ages (5th - 14th centuries CE) and secondary case studies (in Italy and abroad) have been considered to assess the reliability and versatility of the proposed methodology.
In particular, Structure-from-Motion photogrammetry has been tested as a valuable method to digitise historical cartography in order to use it in a GIS software for spatial analysis. This technique has been employed to digitise historical cartography for the main case study as well as to reconstruct the evolution of the Upper Rhone Valley (Valais, Switzerland) at the end of the Little Ice Age (18th- 19th century CE).

Moreover, geoarchaeological and geomorphological tools have been utilised to understand the environmental development of the Central Po Plain and its connection with human settlement dynamics. Geospatial Analysis played a key role in the accomplishment of the project’s goals. GIS software were fundamental to combine different kinds of datasets (archaeo-historical information, remote sensing images and geological maps to name a few) and to perform quantitative studies. In this regard, Point Pattern Analysis highlighted the role of alluvial geomorphology in Late-Holocene settlement strategies in Central Po Plain. Finally, Geoheritage has been used to propose geo-educational plans to encourage the fruition of past landscape features and to increase public awareness on landscape conservation.

Landscapes: the importance of a multidisciplinary approach

Landscapes represent a worthwhile dataset about the millennial human-environment interaction. Therefore, multi-temporal analysis of landscapes dynamics helps in identifying how human economic development and population growth alter natural resources. Moreover, analysing landscape indices and simulating landscape change dynamics ease users in resolving crucial environmental questions regarding:


● the rate progress of landscape changing


● which kind of spatial pattern of land use are ecologically, socially, and economically
beneficial


● sustainable plans for the conservation and the maintenance of natural and cultural resources


Humans are considered the third modifying agent for importance in landscape development (and throughout the centuries the unstable equilibrium between human activities in nature and the ability of the natural system to respond to those activities conditioned the environmental dynamics both at a local and a regional scale. Past landscapes reconstruction enables a better understanding of human resilience to climatic and environmental changes in different periods and places. At the same time, the analysis of past human land-use permit to evaluate the impact of anthropogenic activities on modifying the natural assets of a region, even including early evidence of the inception of the Anthropocene. The diachronic study of landscapes has been carried out in different disciplines such as Earth Sciences, environmental sciences and social and humanities sciences that very often interlaced in the attempt of discerning the effect of the human-environment interplay. Physical geography and Geomorphology are fundamental to comprehend the Earth surface processes, their development under changing climatic conditions and to understand the genesis and evolution of natural landforms. In the last decades, the multidisciplinary combination of Earth sciences tools, environmental sciences approach and social and humanities studies led to conceptualize new methodologies. Therefore, sub-fields in Geomorphology such as Anthropogenic Geomorphology (Szabó, Dávid, and Loczy 2010), Cultural Geomorphology and Archaeo-geomorphology have been
developed mostly to study the role of humans in creating landforms and in modifying the physical
landscapes. On the other hand, since the ‘70s, Earth sciences and geographic tools have been adopted in field and in-lab archaeological research especially when the aim is to understand how environmental conditions influenced the human settlements dynamics. Environmental Archaeology has been developed as the discipline that investigates past environments and “the interaction between them and the human populations which lived in, modified and were modified by them”. In particular, Geoarchaeology is really only one major strand of environmental archaeology, which is the combined study of archaeological records and geological tools to construct integrated models of human-environmental systems and to interrogate the nature, sequence and causes of human versus natural impacts on the landscape. A related field of research that studies the ways in which people in the past reshaped and used the environment around them is represented by Landscape Archaeology. It is an interdisciplinary field, but the varying nature and strength of influences from the humanities, the biological and physical sciences, and the social sciences has shaped different approaches. One of these approaches is Archaeomorphology, an analysis focused on the study of human-made landforms and traces of territorial planning. It aims at analysing the historical development of landscape structures over time and embrace the idea of landscapes as cultural palimpsests.
The differences between all these disciplines developed from Geomorphology, Archaeology and their sub-fields are difficult to be perceived because very often same tools and techniques are applied to address similar goals. In particular, in the last decades, the role of Geographical Information Systems (GIS) and spatial analysis has grown exponentially. GIS software are
undamental to manage different types of datasets in a same project. The analytical power of GIS to
advance innovative understandings of environmental and social aspects in past landscape has been
emphasized by many authors in archaeological studies (Howey and Brouwer Burg 2017) as well as
in geomorphological mapping (Bocco, Mendoza, and Velázquez 2001) and monitoring (Bocco,
Mendoza, and Velázquez 2001; Remondo and Oguchi 2009). The main advantage of GIS is the
integration of spatial and non-spatial information within a unified digital platform, which enables the
exploration of complex patterns in the available datasets. Although GIS are routinely used through
graphical interface, a growing number of scholars rely on coding to implement the most advanced
methods of spatial analysis and map processing. Indeed, the integration of GIS with statistical
computing software enabled quantitative spatial analysis improving our comprehension of the scale
and the patterns of natural (James, Walsh, and Bishop 2012) and human (Carlson 2017) processes in
landscape evolution. The application of geospatial modelling across large areas creates unique
opportunities to gain complementary insights into past landscape. The most popular programming
language for spatial data analysis is currently R (https://www.r-project.org/).
The multidisciplinary approach derived by the combination of the different disciplines
mentioned above is not focused only on the diachronic reconstruction of landscape but on its
protection, management and promotion, as well. As established by the Europen Landscape
Convention (ELC 2000), its members are supposed to increase awareness of the cultural value of
landscapes promoting educational policies on protection, management and planning (ELC 2000).
Landscape might be defined as the result of a continuous synergy between natural processes and
anthropogenic practices: in effect, the landscape is a palimpsest (Orengo and Palet 2016) recording,
the geological and geomorphological history of the Earth and the interactions with human activities
and cultural practices (Gordon 2018). Therefore, in literature, many connections between geoheritage
(Panizza and Piacente 2003; Reynard and Brilha 2017), cultural heritage and landscape (Reynard and
Giusti 2018) have been pointed out as a basis for geoeducational and geotourism activities. The
interconnections between geoheritage and the cultural components of the landscape provide: (1) a
range of opportunities for enhancing the geotourist experience (Chylińska 2019; Pilogallo et al.
2019); (2) a holistic approach for informing landscape conservation policy, management and planning
(Szepesi et al. 2017; Baczyńska, Lorenc, and Kaźmierczak 2018).