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Made available in DSpace on 2020-12-12T02:42:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-07-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Protecting riparian vegetation around streams is vital in reducing the detrimental effects of environmental change on freshwater ecosystems and in maintaining aquatic biodiversity. Thus, identifying ecological thresholds is useful for defining regulatory limits and for guiding the management of riparian zones towards the conservation of freshwater biota. Using nationwide data on fish and invertebrates occurring in small Brazilian streams, we estimated thresholds of native vegetation loss in which there are abrupt changes in the occurrence and abundance of freshwater bioindicators and tested whether there are congruent responses among different biomes, biological groups and riparian buffer sizes. Mean thresholds of native vegetation cover loss varied widely among biomes, buffer sizes and biological groups: ranging from 0.5% to 77.4% for fish, from 2.9% to 37.0% for aquatic invertebrates and from 3.8% to 43.2% for a subset of aquatic invertebrates. Confidence intervals for thresholds were wide, but the minimum values of these intervals were lower for the smaller riparian buffers (50 and 100 m) than larger ones (200 and 500 m), indicating that land use should be kept away from the streams. Also, thresholds occurred at a lower percentage of riparian vegetation loss in the smaller buffers, and were critically lower for invertebrates: reducing only 6.5% of native vegetation cover within a 50-m riparian buffer is enough to cross thresholds for invertebrates. Synthesis and applications. The high variability in biodiversity responses to loss of native riparian vegetation suggests caution in the use of a single riparian width for conservation actions or policy definitions nationwide. The most sensitive bioindicators can be used as early warning signals of abrupt changes in freshwater biodiversity. In practice, maintaining at least 50-m wide riparian reserves on each side of streams would be more effective to protect freshwater biodiversity in Brazil. However, incentives and conservation strategies to protect even wider riparian reserves (~100 m) and also taking into consideration the regional context will promote a greater benefit. This information should be used to set conservation goals and to create complementary mechanisms and policies to protect wider riparian reserves than those currently required by the federal law. Departamento de Ecologia Universidade Federal de Goiás (UFG) Instituto de Biociências Universidade Estadual Paulista (UNESP) Instituto Nacional de Pesquisas da Amazônia (INPA) Departamento de Biodiversidade Universidade Federal do Paraná (UFPR) Programa de Pós-Graduação em Tecnologias para o Desenvolvimento Sustentável Universidade Federal de São João Del Rei (UFSJ) Instituto Amazônico de Agriculturas Familiares Universidade Federal do Pará (UFPA) Laboratório de Hidrologia Florestal Escola Superior de Agricultura Luiz de Queiroz Universidade de São Paulo (USP) Instituto de Ciências Biológicas Universidade Federal do Pará (UFPA) Programa de Pós-Graduação em Biologia UNISINOS Departamento de Genética Ecologia e Evolução Instituto de Ciências Biológicas Universidade Federal de Minas Gerais (UFMG) Instituto de Geociências Departamento de Geografia Universidade Federal de Minas Gerais (UFMG) Laboratório de Ecologia e Conservação de Ecossistemas Aquáticos Universidade Federal de Mato Grosso (UFMT) Centro de Engenharias e Ciências Exatas Universidade Estadual do Oeste do Paraná (UNIOESTE) Laboratório de Sistemática e Ecologia de Insetos Departamento de Ciências Agrárias e Biológicas Universidade Federal do Espírito Santo (UFES) Campus de Ciências Exatas e Tecnológicas Universidade Estadual de Goiás (UEG) Departamento de Ecologia Universidade Federal do Rio Grande do Sul (UFRGS) Laboratório de Organismos Aquáticos (LOA) Departamento de Ciências Biológicas Universidade Estadual de Santa Cruz (UESC) Programa de Pós-Graduação em Ecologia e Conservação Universidade Federal do Mato Grosso do Sul (UFMS) Departamento de Entomologia Museu de Entomologia Universidade Federal de Viçosa (UFV) Instituto de Biociências Letras e Ciências Exatas Universidade Estadual Paulista (UNESP) Laboratório de Ecologia e Conservação Departamento de Engenharia Ambiental Universidade Federal do Paraná (UFPR) Programa de Pós Graduação em Biodiversidade (PPGBC) Universidade Federal do Pará (UFPA) Laboratório de Inteligência Artificial Eletrônica de Potência e Sistemas Digitais Universidade Federal de Mato Grosso do Sul (UFMS) Centro Universitário FG (UNIFG) Instituto Federal de Educação Ciencia e Tecnologia do Sul de Minas Gerais (IFSULDEMINAS) Universidade Federal de Alfenas (UNIFAL) Departamento de Biologia Universidade Federal de Lavras (UFLA) Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais (PEA) Universidade Estadual de Maringá (UEM) Instituto de Ciências e Tecnologia das Águas Universidade Federal do Oeste do Pará (UFOPA) Museu de História Natural Capão da Imbuia (MHNCI) Instituto Nacional de Pesquisa do Pantanal (INPP) Campus Avançado do Museu Paraense Emílio Goeldi (MPEG) Laboratório de Ecologia Centro de Estudos em Recursos Naturais (CERNA) Universidade Estadual de Mato Grosso do Sul (UEMS) Centre for Tropical Biodiversity and Climate Change and Centre for Tropical Environmental and Sustainability Studies College of Marine & Environmental Sciences James Cook University Instituto de Biociências Universidade Estadual Paulista (UNESP) Instituto de Biociências Letras e Ciências Exatas Universidade Estadual Paulista (UNESP) CNPq: 465610/2014-5

Introduction: Snake venom composition shows significant inter- and intra-species variation. In the case of the viperid species Bothrops atrox, responsible for the majority of snakebites in the Amaz...

Streams of protected areas should be subjected to less environmental degradation than surrounding areas and consequently support greater aquatic biodiversity. To test this, 186 environmental and landscape variables were measured in 34 streams within the Caxiuana National Forest (CNF) and its surrounding zone in the eastern Amazon. We expected that streams inside the CNF protected area would have more riparian forest cover and large woody debris (LWD) that increase instream habitat complexity and aquatic biodiversity. Several environmental variables differed between streams in the CNF and surrounding zone; however, the major difference was greater LWD, leaf litter, and channel depth in CNF streams. Richness of fish, Chironomidae, EPT (Ephemeroptera + Plecoptera + Trichoptera), and all-groups combined were positively associated with LWD. Assemblage taxonomic composition was correlated with several variables, but most groups revealed no clear differentiation between the two areas. This lack of differentiation may be explained by relatively minor environmental impacts in areas surrounding the CNF given the region’s small human population. The most notable impact to streams outside of the CNF was removal of LWD to facilitate boat passage. To conserve aquatic biodiversity, we recommend expansion of protected areas and adoption of policies governing land use in surrounding zones.

Our objectives were to assess how turnover and nestedness contribute to beta-diversity patterns of the Zygoptera in Amazonian streams, and to relate these components of beta diversity to environmental, spatial and biogeographic predictors. Our first hypothesis is that the turnover is the most important component of beta-diversity patterns due to the historical isolation of all or part of the areas located in the interfluves of the major Amazonian rivers. Our second hypothesis is that the interaction between environmental conditions and the area of endemism (biogeography) would be the most important predictor of beta-diversity patterns. To test these hypotheses, we compiled data on the Zygoptera communities from 172 Amazonian streams. We used three sets of predictor variables: (i) environmental variables, (ii) area of endemism (biogeographic) and (iii) spatial filters. The turnover explained 99.36% of the beta diversity, corroborating our first hypothesis. Together, environmental and biogeographic variables were the best predictors of beta-diversity patterns. For turnover, however, the biogeographic variables were the best predictors, contrary to our second hypothesis. We found high gamma diversity, but low alpha diversity in the Zygoptera communities. This paradox is explained by the high turnover among sites within the study landscape. This pattern of diversity is related to both historical biogeographic factors and the spatial structuring of environmental conditions in the Amazon region. In the light of our results (high turnover and beta diversity), and their correspondence with areas of endemism, adequate conservation of Amazonian Zygoptera diversity will depend on the establishment of so-called mega-reserves throughout the major Amazonian interfluves and, whenever possible, in the areas with adequate environmental conditions for the greatest possible number of species, otherwise, most species may be at a constant risk of extinction.

Micrurus snakes, commonly known as coral snakes, are responsible for 0.4% of the snakebites envenomings in Brazil. In this report, we describe a case of envenoming by Micrurus averyi, the black-headed coral snake, recorded in the western Brazilian Amazon. To the best of our knowledge, this is the first published case perpetrated by this species. The major complaint of the patient was an intense local pain and paresthesia. Examination of the bite site revealed edema extending from the left foot up the left leg that was accompanied by erythema involving the foot and distal third of the leg. Systemic signs at admission included nausea and drooling. The patient was treated with 100 mL of coral snake antivenom and intravenous analgesics (dipyrone) and was discharged 48 h post-admission with no complaints. The patient showed more intense local edema than that generally described in several other cases of Micrurus bites in Brazil.

a b s t r a c t Thirty streams, located in Manaus in the central part of Brazilian Amazonia, were examined to evaluate the correlations between environmental integrity and the local communities of adult dragonflies and damselflies. The presence of damselflies would have a positive correlation with environmental integrity, and dragonflies a negative one due to their contrasting ecophysiological requirements. The environmen- tal integrity of each site was estimated based on the Habitat integrity index (HII), which was modified for this study in an urban area. The hypothesis that would be differences in assemblage composition between streams in differently urbanized areas was supported, possibly because most damselfly species are considered to be specialists that are found in pristine habitats, whereas dragonflies seem to be generalists and are likely to be found in disturbed environments. The ordination indicated systematic differences in community composition based on the degree of conservation of the environment, with the communities found in well-preserved habitats being distinct from those found in intermediate and degraded ones. Differences in the composition of odonate communities reflect differences in the integrity of the environment, but they can also provide a measure of the intensity of impacts, thus contributing to the development of effective conservation strategies. In addition, the HII, which is applied rapidly and easily, provides environmental managers with an objective measure of the degree of alteration of aquatic habitats. Maintenance of forest cover along watercourses is clearly essential for the conservation of hydrological resources and the aquatic organisms that depend on these environments.