Biodiversity contributes to the ecological and climatic stability of the Amazon Basin^1,2, but is increasingly threatened by deforestation and fire^3,4. Here we quantify these impacts over the past two decades using remote-sensing estimates of fire and deforestation and comprehensive range estimates of 11,514 plant species and 3,079 vertebrate species in the Amazon. Deforestation has led to large amounts of habitat loss, and fires further exacerbate this already substantial impact on Amazonian biodiversity. Since 2001, 103,079–189,755 km² of Amazon rainforest has been impacted by fires, potentially impacting the ranges of 77.3–85.2% of species that are listed as threatened in this region⁵. The impacts of fire on the ranges of species in Amazonia could be as high as 64%, and greater impacts are typically associated with species that have restricted ranges. We find close associations between forest policy, fire-impacted forest area and their potential impacts on biodiversity. In Brazil, forest policies that were initiated in the mid-2000s corresponded to reduced rates of burning. However, relaxed enforcement of these policies in 2019 has seemingly begun to reverse this trend: approximately 4,253–10,343 km² of forest has been impacted by fire, leading to some of the most severe potential impacts on biodiversity since 2009. These results highlight the critical role of policy enforcement in the preservation of biodiversity in the Amazon.

生物多样性有助于亚马逊盆地^1,2的生态和气候稳定，但日益受到森林砍伐和火灾的威胁^3,4。在这里，我们使用火灾和森林砍伐的遥感估计以及亚马逊 11,514 种植物和 3,079 种脊椎动物的综合范围估计来量化过去二十年的这些影响。森林砍伐导致大量栖息地丧失，而火灾进一步加剧了对亚马逊生物多样性的巨大影响。^{自 2001年}以来，103,079–189,755 平方公里的亚马逊雨林受到火灾影响，可能影响到该地区 77.3–85.2% 的濒危物种⁵. 火灾对亚马逊流域物种分布范围的影响可能高达 64%，而更大的影响通常与分布范围受限的物种有关。我们发现森林政策、受火灾影响的森林面积及其对生物多样性的潜在影响之间存在密切联系。在巴西，2000 年代中期启动的森林政策对应于降低燃烧率。^{然而，2019年}这些政策的放松似乎开始扭转这一趋势：大约 4,253-10,343 平方公里的森林受到火灾影响，导致自 2009 年以来对生物多样性的一些最严重的潜在影响。这些结果突出了关键政策执行在保护亚马逊生物多样性方面的作用。