Vers la disparition des brousses ? Analyse multi-scalaire de la dynamique des paysages à l’ouest du Burkina Faso depuis 1952

Cotton countryside in the Western Burkina Faso has rapidly evolved over the last fifty years. Agrarian and demographic transition has led to an important decline in bush areas. A phase of photo interpretation was conducted on a spatial extent comprising a dozen villages along the protected area of the Tui. After a description of spatial patterns with the help of various indicators (shape, structure ...), a summary of the interactions between the protected area and humanized places is proposed. This study shows that even if this area has been protected for 50 years, rules of access to this area have evolved. The rights for cropping of in the 1950’s and 60’s did not exist, and fields eviction were accelerated in the 1990’s. The agrarian transition coupled with strong desire of protection produce then a recent differentiation of two units, one agricultural and one of nature conservation. On this scale of observation, space competition seems to be important. A second approach based on crop/fallow cycles on a finer scale then distinguishes different spatial and dynamics patterns. This broader scale shows that the large increase in cultivated area does not lead to bush extinction. Some farm units continue the practice of shifting cultivation. Ultimately, this work highlights the importance of the relationship between spatial and temporal scales for studying dynamics in this region.