Belterra has a certain degree of pants.
Belterra was founded as a rubber plantation, after the economic failure of Fordlandia, in 1934 by henry Ford. The intention of the US-Department of Commerce in the 1920s was to produce rubber in Brazil and to import it to USA. The advantage of the Belterra plantation vs. the plantation of Fordlandia 100 km to the south is the flat topography, which enables the use of machinery. In its peak time in the late 1930s some 50 km² were cultivated with Hevea Brasiliensis (rubber tree).
In Belterra, new breeding methods with local varieties were applied, which prevented the leaf disease, which happened as a result of the monoculture in Fordlandia. This was very labour intensive and therefore expensive. Together with the worldwide decline on demand on natural rubber, the plantation was not cost effective anymore. Ford sold it to the Brazilian government, which is still running the plantation under EMBRAPA.
Today, the area of the plantation is some 10 - 20 km² covered extensively with mainly old rubber trees. It still gives the impression of a plantation with some 1000 - 2000 inhabitants (mainly plantation workers and their families). At the peak time, it had a population of some 8 - 10,000 people. The entire district population (incl surrounding villages) is given as 16,790 (census 2004)
Amongst soil scientists, Belterra is famous for the underlaying fertile, anthropogenic soil of 'Terra preta', which might have been amongst the criteria for the selection of this site for the plantation. While Terra Preta soil patterns occur all over the Brazilian lowland, this site is extremely well developed and also scientifically surveyed and documented
14C analyses based on Terra Preta ceramic artefacts found in Belterra showed, that this area was populated and cultivated by the indigenous population in an intensive way at least since 500 B.C.
The tertiary highland is composed of some 40 - 50 m clay layers (Belterra clay) of caolinitic sediments of a Pliocene lake, with a distinct escarpement to the North and West of the plain, which leads down to the Varzea lowland at the river bank of the Tapajos river.