<P> The cattle sector of the Brazilian Amazon, incentivized by the international beef and leather trades, has been responsible for about 70% of all deforestation in the region, or about 14% of the world's total annual deforestation, making it the world's largest single driver of deforestation . By 1995, 70% of formerly forested land in the Amazon had been deforested, and 90% of that been converted to cattle ranching . Much of the remaining deforestation within the Amazon has resulted from farmers clearing land for small - scale subsistence agriculture or mechanized cropland producing soy, palm, and other crops . </P> <P> In the pre-Columbian era, parts of the Amazon Rainforest were a densely populated open agriculture . After the European colonization in the 16th century, with the hunt for gold, Western diseases, slavery and later the rubber boom, the Amazon Rainforest was depopulated and the forest grew larger . </P> <P> Prior to the 1970s, access to the forest's largely roadless interior was difficult, and aside from partial clearing along rivers the forest remained intact . Deforestation accelerated greatly following the opening of highways deep into the forest, such as the Trans - Amazonian highway in 1972 . </P> <P> In parts of the Amazon, the poor soil made plantation - based agriculture unprofitable . The key turning point in deforestation of the Brazilian Amazon was when colonists began to establish farms within the forest during the 1960s . Their farming system was based on crop cultivation and the slash - and - burn method . However, the colonists were unable to successfully manage their fields and the crops due to the loss of soil fertility and weed invasion due to this method . </P>

When did the deforestation of the amazon rainforest start
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