Valley floors and high-altitude areas: reinterpreting territorial construction and land value dynamics

In the past, before extensive draining and protection work, valley floors that were not embanked or dammed up were considered inadequate for intensive land use, and even for the establishment of societies, unlike higher up in the valley. However, these lands were not without a certain economic and productive value, thanks notably to the various forms of development which they sustained (production of fodder, lands for grazing, fishing, carriage by river, etc.). They were also in the continuation of the towns and villages of the forelands more or less nearby.

From the beginning of the 19th century, these spaces underwent significant transformations resulting from agricultural innovations and changes to ownership regimes, with the gradual abolition of properties or collective rights to the benefit of individual private ownership. These changes gathered momentum in the 20th century. Certain valleys were altered by industrial installations, which conferred upon them the status and image of "territories of innovation". By the second half of the 20th century, they went from "agricultural plain areas" to areas overshadowed by peri-urbanisation.

At present, certain alpine valley floors are the spaces most subject to anthropogenic pressure, as well as being among the European continent's most dynamic areas from a demographic and economic perspective, thanks to their "territorial connection" role. Conversely, others have become de-populated areas.

Via a time-dependent – and necessarily comparative – approach, this session sets out to verify how territorial transformations of valley floors have impacted the relationships between the low-lying and high-lying lands, modifying the verticality specific to mountain areas. Taking into account the modification of global socio-economic contexts, the session seeks to confirm the impacts of the increased value of high-lying lands on the valley floors.

This will involve verifying the various transformation modalities, depending on the valley, and in particular understanding the impacts on the land of its different usages, which influence the weight of land ownership in decisions. Finally, we must examine how these transformations have modified the system of vertical relations between high lands and low lands, and how they have fuelled innovation processes both on a territorial level and on a social and economic level.

More generally, the session seeks to verify the idea of alpine valley floors sliding from a "fringe" situation (albeit one in continuity with, and highly integrated in, the alpine territory) to one in which their increased value has gone hand in hand with a growing disconnection from the territory to which they belong, or, on the contrary, whether new economic activities have effectively re-connected them to the corresponding territory. Comparisons will serve to gauge the diversity of situations within mountain regions, and to envisage the specificity of these territories based on other criteria.