Amazonian waters, forests, and people are organized in two major groups: The alluvial plains (wetlands) and the interfluvial lands (uplands). Spatial variation of the physical groups is perceived differently depending on the scale of observation and according to two ecological gradients.

  The first gradient is linear, affecting the streams and their banks from upstream to downstream, as for the temperate streams ( fluvial continuum ).

  An areolar gradient is observed from the banks towards the inland, its perception being possible for the huge dimensions of this tropical river basin ( shifting coastline ).

Two types of forest mosaic patterns are observed in the Amazon, mostly depending on opposite processes.

  The interfluvial forests development depends on biotic factors. These forests organization is characterized by a mosaic pattern which is proportional to the grid of the forest regeneration (gaps, chablis).

  The alluvial forests are subject to abiotic, sedimentary and hydric factors, which are responsible for their spatial organization: in this case the forest mosaic is proportional to the scale of the micro-relieves resulting from the alluvial dynamics.

In the current view of an unreasonable exploitation, man prefers to ignore the physical constraints of environments, so the traditional correspondance between the organization of the human activity and the physical groups is deteriorating.

The survival of the Amazon is at stake, in terms of both its biological and cultural richness.

Keywords : Amazon, biodiversity, sustainable development, swamp forests, tropical rain forest, fluvial dynamics, fluvial continuum, shifting coastline, cultural diversity, várzea, terra firme