19 research outputs found

    Pervasive gaps in Amazonian ecological research

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    Pervasive gaps in Amazonian ecological research

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    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

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    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

    Diversidade de formigas (Hymenoptera: Formicidae) em sistemas de cultivo de algodoeiro no Distrito Federal

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    Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Biológicas, Departamento de Ecologia, Programa de Pós-Graduação em Ecologia, 2008.Diversos estudos mostram que as formigas exercem papéis importantes para o funcionamento dos agroecossistemas. Néctar extrafloral, exsudados de pulgões e alta densidade de herbívoros atraem formigas predadoras para o algodoeiro, que poderiam protegê-lo de danos por pragas. Isso dependeria de circunstâncias regionais, da intensidade de manejo de sistemas de cultivo específicos e da densidade e agressividade de formigas dominantes. Os objetivos gerais desse estudo foram avaliar o papel de formigas predadoras enquanto potenciais agentes de controle biológico – por análises de diversidade, composição, pressão de predação e padrões de colonização por assembléias de formigas predadoras - e o de descrever composição de dieta e interações da espécie Labidus praedator (1). Aplicações de agroquímicos, ausência de poda e revolvimento do solo reduzem a riqueza e a densidade de formigas. Maiores densidades de formigas ocorrem em NEF (Nectários Extraflorais) de algodoeiro crioulo G. barbadense, em NEF de G. hisurtum rebrotados e em solo com cobertura morta. Comunidades dominadas por Pheidole e Dorymyrmex estiveram associadas aos distúrbios agroquímicos e de revolvimento do solo, respectivamente. Em sistemas com distúrbio mínimo, Pheidole gertrudae e Crematogaster victima foram dominantes. Em sistemas infestados por curuquerê ou pela lagarta da crotalária, as comunidades de formigas foram dominadas por Solenopsis invicta. Houve uma redução na pressão de predação por formigas em sistemas extensivos. A ocorrência de formigas agressivas é maior em sistemas complexos (e.g., com cobertura do solo permanente e presença de mirmecófitas) e no algodoeiro rebrotado (2). Cinco espécies de três gêneros (Labidus, Nomamyrmex e Eciton) da subfamília Ecitoninae foram registrados. Lagartas foram o principal item da dieta de L. praedator. Arilo e polpa de frutos, flores e diásporos de ervas infestantes também foram transportados. Durante precipitações intensas, L. praedator se agregaram as centenas sob áreas cobertas pela vegetação. Grupos de anus-pretos, marimbondos da subfamília Polistinae e moscas sarcofagídeas acompanharam as frontes de enxame de L. praedator. A importância da estrutura da paisagem para a colonização dos agroecossistemas por Ecitoninae e a existência de oportunismo químico entre formigas de correição são discutidos (3). Ao contrário da mirmecófita G. barbadense, o algodoeiro G. hirsutum var. latifolium perdeu a atratividade às formigas em razão do melhoramento para incrementar a sua produtividade. Ainda assim, em alguns sistemas de cultivo menos perturbados e mais complexos, as formigas podem ter uma contribuição relevante como um dos principais fatores de mortalidade de pragas do algodoeiro (4). _________________________________________________________________________________ ABSTRACTAnts can play important roles to agroecosystems functioning. Cotton nectar, cotton aphid honeydew and high densities of herbivores reward predacious ants that patrol cotton. So, these facultative mutualists can protect cotton from herbivores injury. It depends on regional circumstances, on management intensity of specific cotton systems and on dominant ant density and aggressiveness. The general objectives of this study were to evaluate the role of predatory ants as potential agents of biological control- addressing issues such as diversity, composition, predation pressure and colonization by the assembly of ants- and to describe diet composition and inter-specific interactions of the species Labidus praedator (1). Agrochemicals applications, pruning absence and soil tillage reduced richness and density of predacious ant. Greater ant densities occurred on EFN (Extrafloral nectaries) of Creole Pima cotton G. barbadense, on EFN of G. hirsutum stubble re-sprouting and in mulches on soil. Ant communities dominated by Pheidole and Dorymyrmex, respectively, were associated to agrochemical and tillage disturbances. In minimal disturbance systems, Pheidole gertrudae and Crematogaster victima dominated ant communities. In pest-infested systems by Cotton leafworm Alabama argillacea or by sunnhemp moth Utetheisa in Crotalaria juncea mulch, ant’s communities were dominated by Solenopsis invicta. Due to disturbance effects on nontarget natural enemies, there was a reduction on ant predation pressure at extensive high yield cotton systems. Aggressive ants occurrence is greater on complex cotton systems (e.g., with permanent soil coverage and myrmecophytes presence) and in pruned second year cotton with disturbance reduction and this can partially explain yield differences between cotton cropping systems (2). Five species from three Ecitoninae genera (Labidus, Nomamyrmex and Eciton) were recorded. Caterpillars dominated L. praedator diet composition. Weed’s flowers and diaspores and tree’s fruits aril and flesh were also transported items. One colony stopped foraging activity after intense rainfall and discrete groups of hundreds of L. praedator ants grouped under areas covered by vegetation. Groups of smooth-billed anim birds, polistine wasps and sarcophagid flies followed L. Praedator swarm fronts. We discuss the importance of landscape structure for agroecosystems colonization by Ecitoninae and the existence of chemical opportunism between army ants (3). To the contrary to myrmecophyte Pima Creole cotton (G. barbadense), commercial domesticated cotton varieties (G. hirsutum var. latifolium) seems has lost the EFN attractiveness to ants because of the varietal breeding for increase cotton productivity. Still, in some low-input, semi-perennial or multiple cropping cotton systems ants can play an important contribution as a major mortality factor of pests (4)

    Sinérgico alternativo para inseticidas inibidores de acetilcolinesterase

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    A importância da utilização de sinergistas está relacionada à minimização da quantidade de inseticida químico necessária para o controle de insetos, podendo contribuir com a diminuição da contaminação ambiental e preservação de insetos benéficos. Assim, objetivou-se com este trabalho avaliar o efeito sinérgico e da homogeneidade de resposta de lagartas de Spodoptera frugiperda (J. E. Smith, 1797) às doses subletais do óleo essencial de Piper aduncum L. (OEPA) em combinações com formulações de organofosforados e carbamato, comparadas àquelas com butóxido de piperonila (PBO). Foram obtidos fatores de sinergismo (FS) para comparação dos tratamentos entre si. Por contato residual, evidenciou-se significativa potencialização dos inseticidas Profenofós (FS= 5,4 – 7,7), Fenitrotiona (FS= 3,9 – 29,2) e Clorpirifós (FS= 3,4 – 7,8). Já por contato tópico ocorreu significativa potencialização dos inseticidas: Profenofós + ¼ da DL50 do OEPA (FS= 5,4), Fenitrotiona + ¼ da DL50 do OEPA (FS= 33,8) e Clorpirofós + 1/2 da DL50 do OEPA (FS= 2,5). O metomil não foi sinergizado pelo OEPA nas duas vias de contaminação e não apresentou aumento da pressão de seleção para resistência na população avaliada de lagartas de S. frugiperda. Não foi possível concluir sobre a homogeneidade de resposta e consequentemente da pressão de seleção com relação aos inseticidas organofosforados para S. frugiperda. Os resultados indicam que o óleo essencial de Piper aduncum apresenta potencial como sinergista para Fenitrotiona, Profenofós e Clorpirifós, podendo ser uma alternativa ao butóxido de piperonila

    HTLV-I induces lesions in the pulmonary system: a systematic review

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    Federal University of Pará. Center for Tropical Medicine. Belém, PA, Brazil / State University of Pará. Center for Biological and Health Sciences. Belém, PA, Brazil.State University of Pará. Center for Biological and Health Sciences. Belém, PA, Brazil.Federal University of Pará. Center for Tropical Medicine. Belém, PA, Brazil.State University of Pará. Center for Biological and Health Sciences. Belém, PA, Brazil.State University of Pará. Center for Biological and Health Sciences. Belém, PA, Brazil.State University of Pará. Center for Biological and Health Sciences. Belém, PA, Brazil.State University of Pará. Center for Biological and Health Sciences. Belém, PA, Brazil.Federal University of Pará. Center for Tropical Medicine. Belém, PA, Brazil / Santa Casa de Misericórdia Foundation. Belém, PA, Brazil.State University of Pará. Center for Biological and Health Sciences. Belém, PA, Brazil.Federal University of Pará. Center for Tropical Medicine. Belém, PA, Brazil.State University of Pará. Center for Biological and Health Sciences. Belém, PA, Brazil.Federal University of Pará. Center for Tropical Medicine. Belém, PA, Brazil / State University of Pará. Center for Biological and Health Sciences. Belém, PA, Brazil / Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Ananindeua, PA, Brasil.This study analyzed the relationship between infection by human T-cell lymphotropic virus type 1 (HTLV-1) and changes in the pulmonary system. Cohort and case-control study models that analyzed a causal association between HTLV-1 and changes in the pulmonary system were considered. There were no restrictions on language and publication period. The study was registered in the PROSPERO systematic analysis database (Protocol No. CRD42017078236) and was prepared according to the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. The following databases were used: PubMed, BVS Regional Portal, Embase, CINAHL and Web of Science. We utilized the Newcastle-Ottawa Scale to assess the methodological quality of published studies and the Kappa coefficient to assess the agreement level between two reviewers. Of the total 1156 studies retrieved by the search strategy, 28 were considered potentially eligible (Kappa test = 0.928). Of the 28 studies, three fully met the inclusion criteria. These indicated that pulmonary lesions, such as bronchiectasis and bronchitis/bronchiolitis, were observed in patients with HTLV-1, with high-resolution computed tomography of the chest being the main method of diagnostic investigation. The analyzed cohort and case-control studies indicated an etiological relationship between HTLV-1 infection and the presence of lung lesions, with emphasis on bronchiectasis in the presence of high viral loads, as well as a higher mortality in these individuals compared with the general population
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