Succession management and resource distribution in an Amazonian rain forest

Many Amazonian peoples have a profound effect on rain forest structure and species composition through a process I call succession management. This article describes and examines the extent of such management in a Runa Indian community in Napo Province, Equador. The Runa live in dispersed settlements at low density, below 2 persons/km². Unlike Amazonian people living in concentrated settlements, they are not under strong pressure to intensify succession management in order to concentrate forest resources. In order to assess the magnitude of such manipulation under low density conditions, I compare succession in two managed and two unmanaged five-year-old forest fallows. I found that management increases the species diversity of trees greater than 10 cm dbh (diameter at breast height). Planted tree crops accounted for between 8% and 19% of trees in this size class, and protected secondary species for between 6% and 16%. The distribution of many species, however, was not the result of conscious management decisions, although seedling establishment may have been altered by agriculture. It is possible that succession management in this Runa community could be further intensified to increase the proportion of useful planted and protected species. Nevertheless, resources present in Runa managed fallows provide significant amounts of food, construction material, and firewood as well as medicinal plants and other needed household items. (author)