When man build landforms: Artificial landforms and fictive cities as a new urban heritage
Résumé
In an urban context, man is a physical process which transforms a natural area (the urban site) in an anthropogenic urban landscape. From an urban geomorphology point of view, geologic and geomorphologic features confer the city initial topography, to which societies have to deal with (Coates, 1976). If the natural urban landforms are often profoundly modified and even destroyed, others are preserved and become vectors of identification and are integrated in urban marketing strategies (the hills of San Francisco, the sugar loafs of Rio de Janeiro etc.). Finally, man is also a creator of landforms. Just like natural ones, artificial landforms arise from varied origins and offer a huge diversity of profiles: industrial and mining (heaps, quarries, troglodytes), ornamental (landscaping integration in parks, gardens and zoos), transport (tunnels, channel), architectural (towers, skyscrapers, landforms buildings), archaeological and historic (mottes, grave mounds, embankments, bombing craters, trenches) and "multifunctional" (polders).
Often associated to the history of the city, some of these landforms today emerge as a heritage. This contribution proposes to focus specifically on anthropological landforms in western cities. It follows on from an exploratory inventory of geoheritage of the city of Nantes (France, Kerguillec and Portal, 2015) and widened it. We will see that if the recognition of this anthropogenic heritage is integrated into the history of the city, it is also connected to the natural city, green and mineral, of the XXIth century: disappeared landforms as valleys and filled streams are sometimes redrawn; abandoned heaps become green and are recognized as important biodiversity areas; urban quarries faces are rediscovered and sometimes protected. At last, we will discuss the question of imaginary landforms, anthropogenic by definition, as a pattern for a new heritage feature of the city: artificial mountains will be particularly studied, as anthropogenic mirrors of natural mountains but also as constructions of the urban imaginary, between (science)-fiction and reality of the contemporary city. This proceeding will more widely allow approaching the immaterial dimension of geoheritage.
Often associated to the history of the city, some of these landforms today emerge as a heritage. This contribution proposes to focus specifically on anthropological landforms in western cities. It follows on from an exploratory inventory of geoheritage of the city of Nantes (France, Kerguillec and Portal, 2015) and widened it. We will see that if the recognition of this anthropogenic heritage is integrated into the history of the city, it is also connected to the natural city, green and mineral, of the XXIth century: disappeared landforms as valleys and filled streams are sometimes redrawn; abandoned heaps become green and are recognized as important biodiversity areas; urban quarries faces are rediscovered and sometimes protected. At last, we will discuss the question of imaginary landforms, anthropogenic by definition, as a pattern for a new heritage feature of the city: artificial mountains will be particularly studied, as anthropogenic mirrors of natural mountains but also as constructions of the urban imaginary, between (science)-fiction and reality of the contemporary city. This proceeding will more widely allow approaching the immaterial dimension of geoheritage.