Data from: Deforestation and coca cultivation rooted in twentieth-century development projects

Most of the world's coca—the source of cocaine—is grown in the
Amazonian forests of Colombia, Peru, and Bolivia. As cultivation continues
despite eradication, a shift to giving farmers more incentives to abandon
coca is currently proposed. Assuming coca cultivation is an important
cause of migration and deforestation, new alternative development projects
also aim to conserve forests. We show coca cultivation strongly increases
near never-completed 1960s–1970s state-sponsored projects to settle the
Amazon. Improved roads and colonization projects opened the western Amazon
frontier to migration, generating deforestation and, once support
dwindled, setting the stage for coca cultivation. New studies also show
coca cultivation generates negligible direct or indirect forest loss and
fails to explain migration, whereas expanding legal agriculture, roads,
displacement, and eradication increase deforestation. These findings
highlight the urgent need to both commit development investment for the
long term and set explicit conservation goals in western Amazonia.

全球用于提取可卡因的古柯（coca），绝大多数种植于哥伦比亚、秘鲁与玻利维亚的亚马逊森林中。尽管已开展古柯铲除行动，但其种植规模仍持续扩张，当前学界提出应转向为农户提供更多激励措施，以促使其放弃古柯种植。假设古柯种植是引发移民与森林砍伐的重要诱因，那么新型替代发展项目同样旨在保护森林资源。本研究表明，在1960至70年代国家资助的亚马逊定居项目中，从未完工的区域附近，古柯种植规模出现了显著扩张。完善的道路设施与拓殖定居项目为西亚马逊边境地区带来了移民潮，引发了森林砍伐；而当这类项目的支持力度减弱后，当地便为古柯种植的扩张创造了条件。后续新研究还显示，古柯种植对森林损失的直接或间接影响微乎其微，且无法解释移民现象；与之相反，合法农业扩张、道路建设、人口流离失所以及古柯铲除行动，才是推动森林砍伐的主要因素。上述研究结果凸显了西亚马逊地区长期投入发展资金、并明确设定保护目标的紧迫性。