26 research outputs found

    Indicadores econômicos da produção orgânica de minitomate em casas de vegetação

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    Financial profitability is a factor as important as quantifying production using new technologies. This study was installed to evaluate short and long term financial viability of organic production of cherry tomatoes. Plants were grown in a greenhouse under diverse technological degrees for partial control of micrometeorological elements. The experiment was carried out at the experimental field FEAGRI/UNICAMP in three greenhouses with automated mechanical ventilation systems, evaporative cooling and thermo reflective screen. We cultivated Carolina cultivar in a spacing of 0.5x0.9 m, each plant conducted with two stems, under organic production and fertilization management. The average of production data of treatments {three greenhouses (A= climate-controlled, B= mobile screen and C= fixed screen), two cultivation systems (pots and soil beds) and five biofertilizer doses (0, 50, 100, 150, and 200%)} were evaluated using joint analysis. Thus, the economic indicators {cost benefit ratio (B/C), net present value (NPV), internal rate of return (IRR) and Payback (PV)} were evaluated through revenues and production costs. The best alternative to net monthly cycle profitability (500 m2) was approximately 1 and 1.5 minimum wage with and without particular labor, respectively, associated with the greenhouse of medium technological level, using soil bed cultivation system. The economic viability of the project in long-term interest rates above 3% (a.a) was consistent, but the payback period even with a rate of 1% a.a was high (6.54 years) in financing conditions.362246252A rentabilidade financeira é um fator tão importante quanto quantificar a produção utilizando novas tecnologias. Assim, objetivou-se analisar em curto e longo prazo a rentabilidade financeira da produção orgânica de minitomates em casas de vegetação com diferentes graus tecnológicos de controle parcial dos elementos micrometeorológicos. O experimento foi desenvolvido no campo experimental da FEAGRI/UNICAMP (SP) em três casas de vegetação com sistemas automatizados de ventilação mecânica, resfriamento evaporativo e tela termorrefletora, sendo estas cultivadas com a cultivar Carolina em espaçamento 0,5x0,9 m em duas hastes, e manejo da produção e adubação orgânica. As médias dos dados de produção dos tratamentos {três casas de vegetação (A= climatizada, B= tela móvel e C= tela fixa), duas formas de cultivo (vasos e canteiros) e cinco doses de biofertilizante (0, 50, 100, 150, e 200%)} foram avaliadas em análise conjunta. Assim, avaliou-se através das receitas e custos de produção os indicadores econômicos {relação benefício custo (B/C), valor presente líquido (VPL), Taxa interna de retorno (TIR) e Payback (PV)}. De acordo com os resultados, a melhor alternativa de rentabilidade líquida mensal ciclo (500 m2) foi de aproximadamente 1 e 1,5 salários mínimo para a condição com e sem mão de obra particular, respectivamente, associado à casa de vegetação de médio grau tecnológico, utilizando a forma de cultivo em canteiros. A viabilidade econômica do projeto em longo prazo a taxas de juros acima de 3% (a.a) mostrou-se consistente, porém o período de payback mesmo à taxa de juros 1% a.a foi elevada (6,54 anos) em condições de financiamento

    Plântulas de soja 'Tracajá' expostas ao ozônio sob condições controladas

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    The objective of this work was to assess initial growth, biomass production, gas exchange and antioxidative defenses of soybean 'Tracajá' seedlings, cultivated in the Amazonian region, exposed to ozone under controlled conditions. Seeds germinated in pots were placed in two chambers, one with filtered air (AF) and other with filtered air plus 30 ppb of ozone (AF + O 3). At 10 and 20 days after sowing, gas exchange, growth and biomass were measured; at 20 days after sowing, antioxidative defenses (ascorbic acid and superoxide dismutase) were analyzed. Net photosynthesis, stomatal conductance, transpiration rate, height, leaf area and biomass were 16, 27, 11, 22, 29 and 18% smaller, respectively, in AF + O3 at 10 days after sowing. At 20 days after sowing, besides this parameters, root length, stem diameter and root:shoot ratio were 10, 15 and 12% smaller, respectively, although ascorbic acid concentrations and superoxide dismutase activity increased. Soybean 'Tracajá' seedlings have low tolerance to concentration of 30 ppb of ozone

    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

    The Psychological Science Accelerator's COVID-19 rapid-response dataset

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    The psychological science accelerator’s COVID-19 rapid-response dataset

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    In response to the COVID-19 pandemic, the Psychological Science Accelerator coordinated three large-scale psychological studies to examine the effects of loss-gain framing, cognitive reappraisals, and autonomy framing manipulations on behavioral intentions and affective measures. The data collected (April to October 2020) included specific measures for each experimental study, a general questionnaire examining health prevention behaviors and COVID-19 experience, geographical and cultural context characterization, and demographic information for each participant. Each participant started the study with the same general questions and then was randomized to complete either one longer experiment or two shorter experiments. Data were provided by 73,223 participants with varying completion rates. Participants completed the survey from 111 geopolitical regions in 44 unique languages/dialects. The anonymized dataset described here is provided in both raw and processed formats to facilitate re-use and further analyses. The dataset offers secondary analytic opportunities to explore coping, framing, and self-determination across a diverse, global sample obtained at the onset of the COVID-19 pandemic, which can be merged with other time-sampled or geographic data
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