12 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

    Get PDF
    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

    Modelo de previsão e controle da podridão floral dos citrus causada por Colletotrichum acutatum

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    A podridão floral, causada por Colletotrichum acutatum, afeta flores de citros e induz à abscisão de frutos jovens, sendo considerada um sério problema na maioria das áreas úmidas onde se produz citros nas Américas. O controle da doença é feito pela pulverização de fungicidas durante a florada porém, uma das dificuldades é determinar o momento ideal para o controle. Um modelo de previsão foi desenvolvido na Flórida para indicar a necessidade de pulverização, considerando a quantidade de inóculo, chuvas e molhamento foliar. Este modelo foi avaliado durante três anos consecutivos na região de Itapetininga-SP. Verificou-se que mediante a aplicação do modelo obteve-se um bom controle da doença, tendo-se evitado duas pulverizações desnecessárias em comparação com o calendário, em 1999, e uma pulverização, comparado ao esquema do produtor, em 2000 e 2001. Um novo sistema de previsão para controle da podridão floral (PFD-FAD) foi desenvolvido incorporando outros fatores que também influenciam a ocorrência da doença, como o histórico do pomar, a suscetibilidade da variedade, o estágio de desenvolvimento da florada, assim como chuva, molhamento foliar e nível de inóculo, além da data da última... .Postbloom fruit drop (PFD), caused by Colletotrichum acutatum Simmonds, infects petals of citrus flowers and induces the abscission of fruitlets. The disease can cause serious losses in most humid areas where citrus is produced in the Americas. The disease is controlled by fungicide applications during the bloom but it is difficult to properly time applications. A model was developed in Florida to schedule fungicide applications based on the amount of inoculum and the amount of rainfall and leaf wetness for the last 5 days. This model was evaluated during three consecutive years in Itapetininga-SP, Brazil. Results showed that applications following the model provided good control of the disease and saved two sprays compared to the calendar program in 1999, and one spray compared to the grower’s choice in 2000 and 2001. A new advisory system (PFD-FAD) was developed to be more widely applicable by incorporating risk factors that are inherent in any planting which affected by PFD incidence. The history of the disease in the grove, the varietal susceptibility, the stage of the bloom, as well as the rain, leaf wetness, the amount of inoculum and the last spray date were considered. Field tests in 2001 showed that the system provided good control of the disease with only one fungicide application. Benomyl is considered one of the most effective products for PFD control but despite that C. acutatum is not highly sensitive to benomyl in culture. The mycelial growth and conidial germination is inhibited by 80% at concentration of 1.0 μg/mL, but higher concentrations do not completely inhibit the growth of the fungus. Colletotrichum gloeosporioides, a common saprophyte and causal agent of anthracnose of fruits postharvest, is completely inhibit by 1.0 μg/mL... (Complete abstract, click electronic address below).Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

    Qualidade pós-colheita de goiabas 'Branca de Kumagai', tratadas com cloreto de cálcio

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    Com o objetivo de estudar o efeito do tratamento pós-colheita com cloreto de cálcio, pelo método da temperatura diferenciada, na conservação e qualidade de goiabas 'Branca de Kumagai', conduziu-se experimento em que frutos, na temperatura de 26ºC, foram imersos em soluções de cloreto de cálcio a 5ºC, nas concentrações de 0%; 0,5%; 1,5%; 2,5% e 3,5%. A testemunha foi representada por frutos que não receberam qualquer tipo de aplicação. Após a imersão, os frutos foram mantidos à temperatura ambiente. O tratamento na concentração de 0,5% de cloreto de cálcio estendeu em 34,8% (3,2 dias) o período de conservação dos frutos, reduziu a taxa respiratória e a perda de massa fresca, aumentou ligeiramente os teores de sólidos solúveis totais, sem alterar a acidez titulável e o teor de ácido ascórbico. O tratamento a 0% de cloreto de cálcio reduziu a conservação e aumentou a taxa respiratória dos frutos, indicando que a temperatura da solução de 5ºC, foi prejudicial ao metabolismo dos frutos.A trial was conducted to verify the effect of post-harvest treatment with calcium chloride by the temperature differential method on the shelf-life and quality of guavas 'Branca de Kumagai'. The treatments consisted in dipping fruits with pulp temperature at 26ºC in solutions at 5ºC of different calcium chloride concentrations: 0%, 0,5%, 1,5%, 2,5% e 3,5%. The control did not receive any kind of application. After dipping, fruits were kept under environmental conditions. The treatment with 0,5% of calcium chloride extended the shelf-life in 34,8% (3,2 days), decreased respiration rate and fresh weight loss, slightly increased the total soluble solids content, but not change the acid ascorbic content and the tritable acidity. The treatment at 0% of calcium chloride decreased its shelf-life, indicating that the solution temperature of 5ºC was harmful to the fruit metabolism.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

    Ser e tornar-se professor: práticas educativas no contexto escolar

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    NEOTROPICAL ALIEN MAMMALS: a data set of occurrence and abundance of alien mammals in the Neotropics

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    Biological invasion is one of the main threats to native biodiversity. For a species to become invasive, it must be voluntarily or involuntarily introduced by humans into a nonnative habitat. Mammals were among first taxa to be introduced worldwide for game, meat, and labor, yet the number of species introduced in the Neotropics remains unknown. In this data set, we make available occurrence and abundance data on mammal species that (1) transposed a geographical barrier and (2) were voluntarily or involuntarily introduced by humans into the Neotropics. Our data set is composed of 73,738 historical and current georeferenced records on alien mammal species of which around 96% correspond to occurrence data on 77 species belonging to eight orders and 26 families. Data cover 26 continental countries in the Neotropics, ranging from Mexico and its frontier regions (southern Florida and coastal-central Florida in the southeast United States) to Argentina, Paraguay, Chile, and Uruguay, and the 13 countries of Caribbean islands. Our data set also includes neotropical species (e.g., Callithrix sp., Myocastor coypus, Nasua nasua) considered alien in particular areas of Neotropics. The most numerous species in terms of records are from Bos sp. (n = 37,782), Sus scrofa (n = 6,730), and Canis familiaris (n = 10,084); 17 species were represented by only one record (e.g., Syncerus caffer, Cervus timorensis, Cervus unicolor, Canis latrans). Primates have the highest number of species in the data set (n = 20 species), partly because of uncertainties regarding taxonomic identification of the genera Callithrix, which includes the species Callithrix aurita, Callithrix flaviceps, Callithrix geoffroyi, Callithrix jacchus, Callithrix kuhlii, Callithrix penicillata, and their hybrids. This unique data set will be a valuable source of information on invasion risk assessments, biodiversity redistribution and conservation-related research. There are no copyright restrictions. Please cite this data paper when using the data in publications. We also request that researchers and teachers inform us on how they are using the data
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