While the existence of reciprocal relationships between a landscape, its flora and fauna, and human activities has been widely demonstrated, these relationships deserve to be analysed in detail, taking into account the reciprocal adaptive mechanisms between them.

In the context of pastoral populations, these reciprocal links are particularly important, as they define an eco-cultural niche, the stability of which can vary widely. Throughout this presentation, we wish to show how a given practice can modify the environment, and also to examine the way in which anthropic activities can lead, through reciprocal relationships, to changes in the way in which these same activities are thought.

To illustrate this point more clearly, we will take the example of pastoral reindeer herding populations in Siberia and Fennoscandia, to illustrate firstly how the rise of pastoralism has led to a tundrification of Arctic environments, but also to a tundrification of the populations that have opted for this way of life.

Secondly, we will simply show how reindeer pastoralism modifies landscapes, depending on the techniques employed, and how these modifications tend to call into question the presence of pastoral populations in these same territories.