Spontaneous Colonization and Forest Fragmentation in the Central Amazon Basin

This article addresses the emergence of road networks and forest fragmentation in Central Amazônia, which has been impacted by both spontaneous and planned settlement. The first objective of the article is to broaden the discussion of fragmentation by addressing social processes that generate it through the construction of roads. Roads impact land cover change worldwide, and their role in Amazonian deforestation is known. The article also seeks to extend the literature on roads to address the social processes and individual behaviors that create the road network architecture. The second objective is to open a discussion about the biodiversity implications of different patterns of forest fragmentation. Our specific focus is the geometry of settlement associated with urban nodes, referred to here as radial fragmentation. The article pursues its objectives by implementing a conceptual framework that extends the pattern-to-process paradigm of landscape ecology by adding a (social) process-to-pattern component. This is accomplished through a mixed-method approach including (1) field-based narratives of the social processes that gave rise to radial fragmentation in the hinterland of the town of Itaituba, an important settlement in the middle Tapajós valley; (2) remote sensing of the evolution of road networks, which we then link to deforestation in a temporal analysis of emergent fragmentation patterns; and (3) computational applications to compare the biodiversity implications of radial and fishbone landscape fragmentation.