Entrevoir la construction de niche des Iroquoiens du Saint-Laurent dans les paysages de la vallée laurentienne aux XVIe et  XVIIe siècles : quels enseignements pouvons-nous tirer des feux contrôlés dans la gestion des milieux naturels?

The purpose of this thesis is to contribute to the understanding of the nature and extent of landscape changes by the Iroquoians of the St. Lawrence in the Laurentian Valley in the sixteenth century. As a "living organism" (Homo sapiens), this related cultural group, which occupied a vast territory between the mouth of the Great Lakes and the Gulf of St. Lawrence, was a large resource catchment area and created niches to ensure its reproduction. We are particularly interested in the « footprint » that these niches made to leave on their environment by specifically taking the landscape as a scale of study. We sought to assess the importance or extent of this "transformation". Since it is impossible to "see" these landscapes of the past, we have tried to describe them using descriptions of early explorers, missionaries, adventurers, administrators and European colonizers, on the one hand, and more recent paleoecological and archaeological studies, on the other hand. The approach adopted is that of multidisciplinarity. Protohistorical studies on landscape are relatively infrequent in plant ecology and in the disciplines of planning, we will rely primarily on a literature review in the fields of ethnology, ethnohistory, history, comparative ethnology, geography, ecology, agronomy, palynology, the study of fossil charcoal, archeology and landscape archeology, considering certain landscapes as a realized niche construction. In the end, more of 400 texts were consulted, of which 160 were cited in this master thesis. Illustrations by Samuel de Champlain, explorer and cartographer, on the east coast of New England, and those of the St. Lawrence Valley were studied to determine both their value as "truth" and their value as "knowledge" and thus allow us to "see" the anthropic landscapes of these territories. One of the most effective tools for clearing large part of forests to open up the landscape and allow, among other things, the cultivation of the land is the use of fire. We have identified a number of observations along these lines in northeastern America, but not strictly in the St. Lawrence Valley. The niche created by the Iroquoians of the St. Lawrence was to constitute one or more mosaic-type landscapes. That is, large areas of dense forest could alternate with "park" type forests. The historical sources retained in our memory tend to confirm this type of landscape in certain parts of the Laurentian valley and around the Great Lakes. As part of this master thesis, we are looking to know if the use of fires controlled by Aboriginals for the creation of a niche or for the maintenance of the niche created could be used in the management of natural environments by taking for example the speckled alder (Alnus incana ssp. rugosa) overgrowth in marsh of Lake Saint-François National Wildlife Area.

Keyphrases: Autochtones, Natives, St. Lawrence Iroquoians, Anthropogenic landscape, Niche construction, Realized niches, Laurentian Valley, Precribed Fires, Controlled fires