Segurança alimentar em assentamentos com ênfase ambiental:: um estudo de caso do PDS Virola Jatobá, Transamazônica (PA)

This work analyses the level of food security among family farmers settled in the "agrarian frontier" of the Brazilian Amazon region. The study was conducted in the settlement of PDS Virola Jatobá, in the municipality of Anapu (Pará State). In this modality of environmentally oriented settlements, family farmers devote the areas assigned to alternative use to agricultural activities. On the other hand, the areas identified as legal reserves are employed for extractivist and community forest management activities. A total of 32 interviews and 75 socioeconomic questionnaires were carried out at the family production unit level. Questions aimed at identifying the production, consumption and income values, as well as understanding ongoing productive transformations. Research results allowed the elaboration of a typology, based on the principal activity leading to income generation within the family production unit. The typology pointed out to changes, not only in the traditional production practices and as a consequence of environmental factors, but also in the agricultural production model itself, with different income generation strategies.Este trabalho é uma análise da segurança alimentar de agricultores familiares, em uma região de “fronteira agrária” na Amazônia. A pesquisa foi realizada no assentamento do PDS Virola Jatobá, município de Anapu, Pará. Nessa modalidade de assentamento, os agricultores utilizam as áreas de uso alternativo com atividades agropecuárias e as áreas de reserva legal com o extrativismo e manejo florestal comunitário. Realizaram-se 32 entrevistas e aplicação de 75 questionários socioeconômicos nas unidades de produção familiar com o objetivo de se identificar os valores de produção, consumo e renda, bem como compreender as transformações socioprodutivas. Os resultados da pesquisa permitiram a elaboração de uma tipologia, a partir da atividade preponderante na geração de renda, apontando para mudanças não apenas nas práticas tradicionais de produção em função das questões ambientais, mas também sobre o próprio modelo de produção agrícola, com diferentes estratégias na formação de renda

Segurança alimentar em assentamentos com ênfase ambiental:: um estudo de caso do PDS Virola Jatobá, Transamazônica (PA)

This work analyses the level of food security among family farmers settled in the "agrarian frontier" of the Brazilian Amazon region. The study was conducted in the settlement of PDS Virola Jatobá, in the municipality of Anapu (Pará State). In this modality of environmentally oriented settlements, family farmers devote the areas assigned to alternative use to agricultural activities. On the other hand, the areas identified as legal reserves are employed for extractivist and community forest management activities. A total of 32 interviews and 75 socioeconomic questionnaires were carried out at the family production unit level. Questions aimed at identifying the production, consumption and income values, as well as understanding ongoing productive transformations. Research results allowed the elaboration of a typology, based on the principal activity leading to income generation within the family production unit. The typology pointed out to changes, not only in the traditional production practices and as a consequence of environmental factors, but also in the agricultural production model itself, with different income generation strategies.Este trabalho é uma análise da segurança alimentar de agricultores familiares, em uma região de “fronteira agrária” na Amazônia. A pesquisa foi realizada no assentamento do PDS Virola Jatobá, município de Anapu, Pará. Nessa modalidade de assentamento, os agricultores utilizam as áreas de uso alternativo com atividades agropecuárias e as áreas de reserva legal com o extrativismo e manejo florestal comunitário. Realizaram-se 32 entrevistas e aplicação de 75 questionários socioeconômicos nas unidades de produção familiar com o objetivo de se identificar os valores de produção, consumo e renda, bem como compreender as transformações socioprodutivas. Os resultados da pesquisa permitiram a elaboração de uma tipologia, a partir da atividade preponderante na geração de renda, apontando para mudanças não apenas nas práticas tradicionais de produção em função das questões ambientais, mas também sobre o próprio modelo de produção agrícola, com diferentes estratégias na formação de renda

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

Dossier : Perspectives franco-brésiliennes autour de l’agroécologie – Aux frontières de l’agroécologie. Les politiques de recherche de deux instituts agronomiques publics français et brésilien

L’agroécologie en France et au Brésil résulte d’interactions entre la science, des pratiques agricoles et la politique. Nous analysons la manière dont deux institutions publiques de recherche agronomique, l’Empresa Brasileira de Pesquisa Agropecuária (Embrapa) et l’Institut national de la recherche agronomique (Inra), appréhendent ces frontières à l’occasion de sa mise sur leur agenda de programmation. Notre analyse montre comment leurs exercices de programmation étant, plus ou moins, dépendants de leurs contextes politiques nationaux, il en résulte des dynamiques et des cadrages différents de la notion. Précédant l’Inra, l’Embrapa, fortement incité par le gouvernement et les mouvements sociaux, intègre l’agroécologie pour légitimer une recherche alternative, au service des agriculteurs familiaux dans un contexte agricole et politique très clivé et houleux. À l’Inra, l’agroécologie permet la (re)légitimation de l’agronomie pour répondre aux enjeux sociétaux actuels, tout en rejetant la radicalité politique des mouvements sociaux. Elle trouve ensuite un écho dans la politique publique. Nous montrons enfin que la notion donne lieu à des cadrages et débats internes au sein des deux institutions reflétant différentes conceptions du rapport science/société

Transpiration and canopy conductance of secondary vegetation in the eastern Amazon

Secondary woody vegetation in the Brazilian Amazon accounts for about 30% of the cleared area in this region, which exceeds 100,000 km2. Despite the relative predominance of secondary vegetation, the hydrological and climatic properties of these areas are not well documented. In an effort to address this, the evapotranspiration (E) of a 3.5-year-old secondary vegetation in the eastern Amazon of Brazil was measured over 1 year. The annual evapotranspiration according to the Bowen ratio energy balance (BREB) amounted to 1421 mm, which is equal to rates quoted for tropical primary forests. The secondary vegetation returned 73% of the annual rainfall (1954 mm) to the atmosphere. Evapotranspiration required 73% of the net-radiation (Rn) energy; this function remained fairly constant over the whole year. In order to estimate evapotranspiration with the Penman-Monteith (PM) method, the canopy conductance (gc) was determined using the BREB results. The monthly mean daily gc varied between 14 and 22 mm s-1 in the rainy season and the transitional period (January-August), and reached a minimum of 7 mm s-1 in the dry season in October. The hourly as well as daily mean canopy conductance were approximated by a multiple linear regression analysis incorporating hourly and daily averages of Rn and vapour pressure deficit, respectively. In addition, the Jarvis-type model, which is based on a set of environmental control functions, was applied to predict hourly gc. The multiple linear regression and the non-linear optimisation (Jarvis-type model) were equally suitable for gc prediction. The optimised environmental control functions were comparable to those predicted elsewhere for Amazonian primary forests. This underlines the similarity of secondary and primary forests with respect to hydrological characteristics as well as energy turnover. © 2002 Elsevier Science B.V. All rights reserved