19 research outputs found

    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

    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

    Comparative analysis of the relative growth of Uca rapax (Smith) (Crustacea, Ocypodidae) from two mangroves in S\ue3o Paulo, Brazil

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    A study on the relative growth of two populations of Uca rapax (Smith, 1870) was performed primarily to determine the size at onset sexual maturity. The species was sampled monthly in Itamambuca (23º24'43"S and 45º00'73"W) and Ubatumirim (23º20'17.8"S and 44º53'2.2"W) mangroves. Carapace width (CW) and length (CL), abdomen width (AW), major cheliped propodus length (PL) and height (PH) for each sex, and gonopod length (GL) for males were measured with a calliper (0.01 mm). Allometric analyses were used to estimate size at maturity. The relationships that most precisely indicated the size at onset of sexual maturity were AW vs. CW, for females and PL vs. CW, for males. Males and females are mature, respectively at 15.2 and 12.1 mm CW in samples from Itamambuca and 13.5 and 11.2 mm CW in samples from Ubatumirim mangrove. Positive allometric growth of females abdominal width is likely related to the incubation process, while positively allometry growth of male's cheliped almost certainly relates to reproductive behaviour.<br>O estudo do crescimento relativo foi utilizado para determinar quais dimensões evidenciam melhor a maturidade sexual morfológica de Uca rapax (Smith, 1870). Os caranguejos foram coletados mensalmente nos manguezais de Itamambuca (23º24'43"S e 45º00'73"W) e Ubatumirim (23º20'17,8"S e 44º53'2,2"W), em período de maré baixa. Os caranguejos de ambos os sexos foram mensurados com um paquímetro (0,01 mm) quanto à largura da carapaça (LC), comprimento da carapaça (CC) e largura do abdome (LA). Nos machos mensurou-se ainda o comprimento e altura do própodo do quelípodo maior (CPQ e APQ) e comprimento do gonopódio (CG) e, no caso das fêmeas, comprimento e altura do própodo do quelípodo direito (CPQ e APQ). As análises alométricas foram utilizadas para estimar o tamanho da maturidade sexual morfológica. As relações que melhor evidenciaram o tamanho da maturidade foram LA vs. LC para fêmeas e CPQ vs. LC para machos. Machos e fêmeas estão maduros morfologicamente, respectivamente com 15,2 e 12,1 mm de LC em Itamambuca e 13,5 e 11,2 mm de LC no manguezal do rio Ubatumirim. O crescimento alomético positivo da largura do abdomen de fêmeas está relacionado com o processo de incubação, enquanto a alometria positiva do quelípodo dos machos pode estar relacionada ao comportamento reprodutivo

    Estudo soroepidemiológico da cisticercose humana em um município do Estado do Piauí, Região Nordeste do Brasil Seroepidemiological survey of human cysticercosis in a municipality of Piaui State, Northeast Brazil

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    Integrando as pesquisas sobre parasitoses na região do entorno do Parque Nacional Serra da Capivara, Piauí, Brasil, realizadas entre 1999 e 2001, o presente estudo tem como objetivo avaliar a situação epidemiológica da cisticercose humana no Município de João Costa, no Nordeste do Brasil. Foram obtidas informações clínico-epidemiológicas e coletadas amostras de sangue para testes sorológicos imunoenzimáticos (ELISA e Western blot), empregando cisticercos de Taenia crassiceps como antígeno. Na primeira etapa, em 1999, foram investigadas 169 pessoas com história confirmada ou suspeita de infecção/doença pelo complexo teníase-cisticercose, e seus familiares. Na análise, 13,6% das pessoas apresentaram soros reagentes para cisticercose pelo método ELISA. Na segunda etapa, em 2001, foram avaliadas 92 amostras de soro de indivíduos reativos para cisticercose detectados no primeiro momento e seus familiares, sendo que 24,0% das amostras de soro foram reagentes para cisticercose pelo ELISA, e 29,0%, pelo WB. Nessa mesma etapa, realizou-se inquérito coprológico em 701 pessoas, incluindo voluntários. A prevalência de parasitoses intestinais foi de 51,0%, tendo sido observada uma maior prevalência de protozoários (95,0%) em relação aos helmintos (5,0%). Os resultados do estudo indicam o caráter endêmico da cisticercose na área, além da elevada freqüência de protozooses intestinais.<br>As part of parasitological studies in the area surrounding the Serra da Capivara National Park, Piauí State, Northeast Brazil, from 1999 to 2001, the current study aimed to evaluate the epidemiological profile of human cysticercosis in the Municipality of João Costa. Clinical and epidemiological data were obtained, and blood samples were drawn for immunoenzymatic serological tests (ELISA and Western blot), using Taenia crassiceps as the antigen. The first stage, in 1999, investigated 169 individuals with a confirmed history or suspicion of infection/disease involving the teniasis/cysticercosis complex, along with the family members. Some 13.6% of the individuals were seroreactive for cysticercosis by the ELISA method. The second stage, in 2001, evaluated 92 serum samples of individuals who had been detected as reactive for cysticercosis in the first stage, along with their family members; 24% of the samples were reactive to cysticercosis by ELISA and 29% by Western blot. During this same stage a coprological survey was performed with 701 individuals, including volunteers. Prevalence of intestinal parasites was 51%, with a higher prevalence of protozoans (95%) than helminths (5%). The results indicate the endemicity of cysticercosis in the area, in addition to the high frequency of intestinal protozoan infections
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