83 research outputs found
A Constituição do sistema participativo de garantia do sul de Minas
Os Sistemas Participativos de Garantia (SPG) visam assegurar, por meio do processo de avaliação participativa da conformidade, a garantia de que um produto, processo ou serviço atende a regulamentos técnicos da agricultura orgânica. Apesar de ter sido regulamentado em 2009, poucos grupos de agricultores conseguiram constituir um SPG. A experiência do Sul de Minas na constituição do seu SPG tem chamado a atenção de vários grupos. Para realização deste trabalho, utilizou-se da análise documental e observação participante como procedimentos técnicos metodológicos. Seu objetivo foi resgatar o processo de constituição do SPG Sul de Minas, para que possa servir de referência teórica e prática para outros grupos de agricultores e técnicos que queiram conhecer o processo de constituição de um Sistema Participativo de Garantia. Constatou-se que o histórico dos agricultores da região com a Agroecologia e agricultura orgânica e as parcerias foram aspectos que contribuíram para a constituição e consolidação do SPG Sul de Minas
The contribution of the participatory guarantee system in the revival of agroecological principles in southern Minas Gerais, Brazil
Market pressures generated by the demand for organic food have pushed farmers to turn away from agroecological principles, which leads to actions focused directly on the agricultural practices for production. The objective of this study was to analyze whether the methodology used by the Participatory Guarantee Systems (PGS) contributes to farmers' appropriation of agroecological principles, understood here in their environmental, sociocultural, economic, and political dimensions. We analyzed the PGS-Sul de Minas, which was the first PGS founded in the state of Minas Gerais, Brazil and includes 14 organizations and more than 200 families. Documentary analysis and participant observation were prioritized in data collection. The main results are the correlation between the practices used by the farmers in these organizations with the principles of agroecology. This is evident in aspects such as the encouragement of productive diversification, the construction of new marketing alternatives, the revival and use of heirloom seeds, the stimulation of women's leadership, and places and policies that support and strengthen agroecology. The study found that the procedures adopted by the PGSs help strengthen agroecology and bring direct benefits to the farmers through revival and encouragement of agroecological principles1117COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESsem informaçã
AGRICULTURA FAMILIAR, CULTURA LOCAL E POLÍTICAS PÚBLICAS: O CASO DOS LAVRADORES DO ALTO JEQUITINHONHA
Agricultura familiar e programas de desenvolvimento rural no Alto Jequitinhonha
The agrarian conditions and the low relative levels of the socioeconomic indicators cause the area of the “High Jequitinhonha Valleyâ€, in the northeast of the State of Minas Gerais, to be considered one of the most complex areas of Brazil. For this reason several governanmental administrations have recommended rural development programs. Most of these efforts, however, have not produced adequate results. This article analyzes the relationships between public programs and family farming, making a survey of the methods and results of the last three decades. It concludes that there is a need to incorporate the specificities of history, environment and culture into the rural programs. It is suggested that the programs take into consideration the experience accumulated by the regional organizations and be adjusted to the interest and culture of the local family producers.family farming, rural extension, rural development, public programs, Jequitinhonha Valley., Agribusiness, R58, Q15,
Estado da arte em agroecologia e suas relações com experiências no sul de Minas Gerais
O presente trabalho procurou identificar inovações tecnológicas no campo da agroecologia, com base em trabalhos científicos em nível mundial e as suas relações com as experiências agroecológicas do Sul de Minas Gerais. Foi realizada pesquisa bibliográfica e bibliométrica abrangendo estudos científicos sobre agroecologia e agricultura orgânica. Para isso, foi realizado uma busca nas bases de periódicos SciVerse Scopus, Web of Science e Scielo. Foi sistematizado o estado da arte em agroecologia. Ao mesmo tempo foi feita uma pesquisa ao nível de campo como um estudo de caso, caracterizando e mapeando as experiências regionais por meio de questionários semiestruturados. Após as coletas e análises dos dados provenientes do conhecimento científico e da prática das famílias agricultoras, foi possível realizar relações entre os dois conhecimentos. Foram contabilizados 4.739 registros de documentos científicos. Foram entrevistadas 10 organizações de agricultores. Foram identificadas técnicas e inovações em agroecologia, obtendo-se uma alta relação entre os conhecimentos científicos e a prática local dos agricultores agroecológicos do Sul de Minas Gerais
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
Geographic patterns of tree dispersal modes in Amazonia and their ecological correlates
Aim: To investigate the geographic patterns and ecological correlates in the geographic distribution of the most common tree dispersal modes in Amazonia (endozoochory, synzoochory, anemochory and hydrochory). We examined if the proportional abundance of these dispersal modes could be explained by the availability of dispersal agents (disperser-availability hypothesis) and/or the availability of resources for constructing zoochorous fruits (resource-availability hypothesis).
Time period: Tree-inventory plots established between 1934 and 2019.
Major taxa studied: Trees with a diameter at breast height (DBH) ≥ 9.55 cm.
Location: Amazonia, here defined as the lowland rain forests of the Amazon River basin and the Guiana Shield.
Methods: We assigned dispersal modes to a total of 5433 species and morphospecies within 1877 tree-inventory plots across terra-firme, seasonally flooded, and permanently flooded forests. We investigated geographic patterns in the proportional abundance of dispersal modes. We performed an abundance-weighted mean pairwise distance (MPD) test and fit generalized linear models (GLMs) to explain the geographic distribution of dispersal modes.
Results: Anemochory was significantly, positively associated with mean annual wind speed, and hydrochory was significantly higher in flooded forests. Dispersal modes did not consistently show significant associations with the availability of resources for constructing zoochorous fruits. A lower dissimilarity in dispersal modes, resulting from a higher dominance of endozoochory, occurred in terra-firme forests (excluding podzols) compared to flooded forests.
Main conclusions: The disperser-availability hypothesis was well supported for abiotic dispersal modes (anemochory and hydrochory). The availability of resources for constructing zoochorous fruits seems an unlikely explanation for the distribution of dispersal modes in Amazonia. The association between frugivores and the proportional abundance of zoochory requires further research, as tree recruitment not only depends on dispersal vectors but also on conditions that favour or limit seedling recruitment across forest types
Mapping density, diversity and species-richness of the Amazon tree flora
Using 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness. Using only location, stratified by forest type, as predictor, our spatial model, to the best of our knowledge, provides the most accurate map of tree diversity in Amazonia to date, explaining approximately 70% of the tree diversity and species-richness. Large soil-forest combinations determine a significant percentage of the variation in tree species-richness and tree alpha-diversity in Amazonian forest-plots. We suggest that the size and fragmentation of these systems drive their large-scale diversity patterns and hence local diversity. A model not using location but cumulative water deficit, tree density, and temperature seasonality explains 47% of the tree species-richness in the terra-firme forest in Amazonia. Over large areas across Amazonia, residuals of this relationship are small and poorly spatially structured, suggesting that much of the residual variation may be local. The Guyana Shield area has consistently negative residuals, showing that this area has lower tree species-richness than expected by our models. We provide extensive plot meta-data, including tree density, tree alpha-diversity and tree species-richness results and gridded maps at 0.1-degree resolution
Consistent patterns of common species across tropical tree communities
Trees structure the Earth’s most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1,2,3,4,5,6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth’s 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world’s most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees.Publisher PDFPeer reviewe
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