The "colocações" map on the Tejo River Basin, AC, in the scale 1/100.000 recognizes a total of 145 "colocações" distributes along rivers and "igarapés" (annexed). With a density of approximately 1 colocação/28 Km2, each group explores a certain area of the forest through vegetal and animal extrativism, and they cut approximately 2 to 5 ha for farming and cattle raising activities.
In the map, many spots having the same nomenclature represent areas of small plantations, pastures and the yard of each "colocação".
The "Restauração", has approximately 10 houses and is the main local cooperative center. Besides this, the rubber tapper's association maintains many other centers at other points of the Tejo River Basin. Transportation on the area is made through canoes by rivers and "igarapés" or on foot by trails on the interior of the forest.
In a regional context, the Amazon may be different of the rest of South America physiographically and biologically due to its dense forest and great biomass (PIRES & PRANCE, 1985).
The forests occur when the basal area reaches around 10 m2/ha. Generally characterized by the lack of Poaceae and Cyperacea families, the denser the forest the lesser importance the shrub strata have, such as herbaceous plants and lianas (PIRES & PRANCE op. cit.).
On the satellite images we tried to identify the "isófena" zones: similar areas on the landscape.
Two types of vegetal formation occur in the forest. They are associated to different climates, geological formation, type of relief and ecological conditions, even the local inhabitants recognize the vegetal diversity of the areas in which they live. Each area has its own name, its own limits.
In the Tejo River Basin there are 5 basic main vegetation units:
On the border of these homogeneous formations, there are complex associations.
The "firm soil" forest, as is called by the rubber tappers, is the main forest type on the Tejo River Basin. This covers approximately 90% of the Amazon forest, and is characterized by a vegetal formation of great biomass, high trees, closed canopy and a few vines (GOODLAND & IRWIN, 1975). In this part of Acre, the forest or "firm soil" forest is also described as open tropical forest with palms (RADAM Javari).
Different from the "igapó", which is flooded only part of the year; the "varzea" forest is located near waterways, which is periodically flooded according to its height in relation to the river or "igarapé". Despite the fact that the "varzea" forest shows a reduced biological diversity and a lower height than the ''firm soil" forest, in the first forest one can also find tall tree species such as "samaúma" (Ceiba pentandra), "tachi", "pau mulato", "sororoca", etc. The open "varzea" forest is less dense than the closed "varzea" forest, but it occurs usually in areas where there is an intense humidity.
The fields have small trees with many branches and several tree-growing plants. This kind of vegetation is found all over Acre state, but some are in very isolated areas, contributing to the biodiversity in the region. In the Tejo River Basin you can find the field formations of the Machadinho and Preto rivers.
