ANÁLISE DAS TAXAS DE DESMATAMENTO E SEUS FATORES ASSOCIADOS NA AMAZÔNIA LEGAL BRASILEIRA NAS ÚLTIMAS TRÊS DÉCADAS

O bioma Amazônia possui a mais extensa floresta tropical do planeta. O seu papel fundamental no equilíbrio climático, assim como a intensificação das atividades econômicas que têm degradado a cobertura vegetal nas últimas décadas, evidenciam a necessidade da conservação da Amazônia. Este artigo tem como objetivo analisar as taxas de desmatamento na Amazônia Legal Brasileira (ALB) ao longo da série histórica do Projeto de Monitoramento do Desmatamento na Amazônia Legal por Satélite (PRODES) e discutir os valores de perda de floresta acumulados até o ano de 2020 em cada unidade federativa. Ao longo da série PRODES, as maiores taxas de desmatamento foram registradas em 1995 e em 2004, motivadas, respectivamente, pela implantação do Plano Real e pela recuperação da economia do país, devido à estabilização da moeda – o que impulsionou a economia, inclusive em setores ligados ao agronegócio. A crise das commodities, a criação de políticas públicas e ações de fiscalização contribuíram para a redução do desmatamento até 2012. Todavia, a partir de 2013 as taxas voltaram a crescer, estimuladas pelo enfraquecimento da legislação ambiental e das ações de combate ao desmatamento e pela conjuntura econômica favorável a expansão das atividades agropecuárias. Cerca de 20,62 % das florestas originais da ALB foram suprimidas até 2020, sendo que os estados com maior perda florestal são o Pará, Mato Grosso, Maranhão e Rondônia

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

República, democracia e federalismo Brasil, 1870-1891 Republic, democracy and federalism Brazil: 1870-1891

A transformação dos radicais liberais em republicanos, ocorrida a partir do Manifesto Republicano de 1870, provocou um retrocesso conservador e suspendeu o programa de reformas sociais e políticas, proposto pelos radicais durante a década de 1860. Esse artigo tenta explicar essa mudança examinando a formação do campo conceitual republicano entre 1870 e a promulgação da Constituição de 1891.<br>The transformation of Liberal Radicals into Republicans at the time of the publication of Republican Manifest in 1870 meant a conservative turn and halted the program of social and political reforms proposed by the Radicals during the 1860's.This article tries to explain the change analysing the formation of the Republican conceptual field between 1870 and the promulgation of the Constitution of 1891

A república e o sonho The republic and its dream

O desencanto com a República brasileira tem sido tema de reflexões desde os seus momentos iniciais. Buscando os conteúdos concretos dos sonhos republicanos na década de 1880 e na Primeira República vamos achar uma importante defasagem entre eles não exatamente em função do marco cronológico, mas do grupo social que, respectivamente, os acalentou.<br>The disillusion with the Brazilian Republic since its first days has been a topic of academician reflexions. Examinating the concrete contents of the 1880`s and the First Republic republican dreams we will find a substantive difference between them. To be exact, this difference must not be related to the chronological demarcation but to the social group that embraced each of them