Mudanças contemporâneas da Amazônia: Impactos sobre povos indígenas, novas dinâmicas epidemiológicas e efeitos climáticos sobre a biodiversidade

Abstract

Contemporary changes in the Brazilian Amazon are at a critical juncture due to a huge rollback of environmental legislation and the dismantling of enforcement agencies, which has led to an explosive increase in deforestation, fires, land grabbing, illegal mining and other activities that degrade the biome. The Brazilian government has also taken a series of measures to facilitate large infrastructure projects that promote deforestation, such as the BR-319 highway that connects Porto Velho (in the arc of deforestation) to Manaus (in the still relatively intact central Amazon). In addition, new cycles of deforestation have been generated by the expansion of cattle ranching and of agricultural crops for biofuels. The federal government has also promoted a legislative change to open indigenous lands to livestock and monocultures, putting the biodiversity of these areas and their resident traditional peoples at risk. In this thesis we documented major threats to indigenous peoples, such as the lack of consultation as required by International Labor Organization (ILO) Convention 169 in the project to rebuild the BR-319 highway, which threatens 18,000 indigenous people who occupy 63 indigenous lands that are officially recognized by the government, plus another five unofficial communities, in addition to a population classified as “isolated.” We also tested the hypothesis that the deforestation observed in these areas is due to the promise of paving the road, which was confirmed by the explosion of deforestation in buffers of both 40 km and 150 km from each side of the road, coinciding with the beginning of the BR-319 “maintenance” program in 2015. We also found that the advance of threats to the forest and actions by the federal government weakening the protection of the biome in the midst of the new coronavirus pandemic drastically affected traditional populations. A series of violations of the rights of indigenous peoples was promoted by the federal government, including the participation of the Brazilian Army, and the federal government used the COVID-19 pandemic as a smokescreen to cover up both the environmental degradation and the violation of rights. The coronavirus pandemic (COVID-19) transformed the region into one of the global epicenters of the pandemic, having as its cause the same governmental negligence that failed to curb the advance of deforestation and degradation of the Amazon Forest. The results of this thesis demonstrated that the Amazon quickly became the global epicenter of the COVID-19 pandemic due to the neglect and denialism of the federal and state governments, which caused a second and more intense wave of COVID-19 in the region. Through epidemiological models of the SEIR type (Susceptible-Exposed-Infected and Recovered), it was shown that Manaus never reached herd (collective) immunity against the coronavirus. The Federal government and Amazonas state government’s authorization of an early return to face-to-face activities gave rise to the second wave of COVID-19 in the region and the emergence of the gamma variant, which was responsible for two thirds of deaths in Brazil. A case study documented the first case of reinfection in the Amazon region, in addition to the loss of immunity due to natural contact with the virus, reinforcing the need for vaccination. The third wave of COVID-19 for the Amazon was foreseen by our SEIR- type epidemiological models, which indicated the need to increase vaccination for the entire population, in addition to identifying the appropriate vaccination thresholds needed to minimize a fourth wave and later eradicate severe forms of COVID-19 through an annual or biannual booster vaccination. Climate change is already underway and is accelerated by the degradation and deforestation of the Amazon, a region that is on the verge of passing the maximum level of deforestation that the forest can tolerate. This climate change can greatly affect biodiversity, and the present thesis shows the projected impact on frogs in the central Amazon. Even frog species that are now considered common and out of danger would suffer population declines and extinctions between the middle and the end of this century due to predicted climate change. It was also demonstrated that the water transported from the Amazon by the “flying rivers” contributed to the diversification of the morphological traits of the frogs in the Atlantic Forest, and that the disruption of this ecosystem service by the advance of deforestation would tend to cause population declines for these frogs. This thesis also explored the question of whether historical amphibian declines in Brazil are more associated with climate change and extreme weather events than with the mega-pandemic caused by Batrachochytrium dendrobatidis (Bd), which is a fungus that can be lethal to amphibians and has been responsible for various species declines and extinctions around the world. Our results show that it is implausible that Bd is responsible for the historical population declines of Brazilian amphibians, and that these declines and extinctions are instead associated with extreme weather events or climate change at the locations where these species occur. This result further reinforces the risk that projected climate change poses to amphibians. Our results show that the imminent need to promote the conservation of the Amazon and protect its traditional peoples and ecosystem services. Among the potential impacts of the collapse of biodiversity observed and projected here is the risk of emergence of new pandemics that Brazil does not have the least capacity to mitigate, as demonstrated by the Brazilian response to the COVID-19 pandemic. In short, the current and projected impacts of contemporary changes in the Amazon are extremely serious, both through direct human action and through anthropogenic climate change.