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Notes on morphology and distribution of <em>Acmanthera</em> (A. Juss.) Griseb. (Malpighiaceae), an endemic genus from Brazil
No full textCaracterização dos frutos de Pupunheira (Bactris gasipaes Kunth) cultivada na vila do Equador, RR: O que há de novo?
Get PDFAislamiento de triptamina y actividad antiangiogénica de Warszewiczia schwackei (Rubiaceae)
No full textPadrões geográficos e conservação de aves nos habitats criados por rios na Amazônia
Get PDFRivers are fundamental features in the Amazonian biogeography. Despite that, specialization by birds in river-created habitats seems to have been under-appraised in most of biogeographical studies and synthesis. River-created habitats comprise a complex mosaic of forests and other vegetation types at distinct stages of succession, with variations related to river color or type. Extending almost linearly along rivers and covering more than 15% of the Amazon basin, these habitats shelter a rich avifauna, with more than 100 specialized or exclusive species. In this thesis, we investigated how Amazonian floodplain birds are distributed. In the first chapter, we set out to test the power of the “color” of rivers in predicting differences in the avifauna among sites in the Rio Negro basin. Based in bird standardized surveys at distinct tributaries, we showed species compositions were significantly distinct between black- and whitewater rivers. Several indicators species supported distinctions and the water type of the rivers arose as a first factor to understand general range patterns for floodplain specialized birds. On the other hand, “intermediary” avifaunas were found at some sites; and in the second chapter, we investigated if and how the confluence with Rio Branco, affects the avifauna along Rio Negro itself, which is the world’s largest blackwater river. We sampled islands and riverbanks along the middle and the lower Rio Negro, above and below, respectively the confluence with the Rio Branco, and compared with sampling from the Rio Branco itself. These surveys indicated a combination of avifaunas, with higher richness below the confluence. Moreover, overall variation in species composition along the confluence was correlated with distinct levels of sediment concentration in the water (a proxy for water type), supporting the importance of this factor to the occurrence of birds in the floodplains. This phenomenon, involving waters and avifaunas, expressed the potential multiple roles (isolating, connecting and maintaining habitats) of the several confluences between large Amazonian rivers of distinct water types on the distribution of floodplain biodiversity. Finally, in the third chapter, we reviewed and analyzed geographic distributions of floodplain specialized bird species. Occurrence data on an updated list of specialized taxa supported at least eleven potential specific areas of endemism, essentially distinct from large interfluvial areas that are valid for terra firme birds. A parallel subdivision of Amazonia with at least nine regions, based solely on the distributions of floodplain specialized birds emerged as an alternative background for evolutionary studies and conservation of the floodplains biodiversity. From a conservation perspective, the dependency of the avifauna on micro-habitats that are geographically restrict implies high vulnerability for floodplain specialists. Although large tracts of river-created habitats are covered by protected areas, populations of floodplain specialized birds are vulnerable given the plans of damming several Amazonian rivers, which might alter the formation and availability of these micro-habitats. In synthesis, this thesis expresses the biogeographic specificities for Amazonian floodplains. Range patterns for specialized birds reflect broadly the ecological distinctiveness and the complex history of rivers draining different regions. River-created habitats offer interesting opportunities to a better understanding of the richness and evolution of the Amazonian avifauna and total biodiversity.Os rios são os aspectos mais marcantes na biogeografia da Amazônia. Apesar disso, as aves especialistas nos habitats criados pelos próprios rios (i.e., ambientes alagáveis) parecem ter sido ignoradas na maior parte dos estudos e sínteses biogeográficas. Esses habitats ribeirinhos compreendem um complexo mosaico de florestas e outras fitofisionomias em diferentes estágios de sucessão, que variam de acordo com a cor ou o tipo de água dos rios. Cobrindo ao menos 15% da bacia amazônica, os ambientes alagáveis abrigam uma rica avifauna, com mais de 100 espécies exclusivas e especialistas. Nessa tese, nós investigamos como as aves especialistas nos habitats criados por rios estão distribuídas. No primeiro capítulo, nós testamos o poder da classificação dos rios de acordo com a cor da água (branca ou preta) em prever diferenças na avifauna entre localidades na bacia do Rio Negro. Com base em amostragens padronizadas das aves ao longo de diferentes tributários, nós mostramos que embora a riqueza de espécies tenha sido similar, a composição foi significativamente distinta entre rios de água branca e preta. Várias espécies indicadoras suportaram essa distinção e o tipo de água dos rios despontou como um instigante ponto de partida para entender os padrões gerais de distribuição das aves especialistas nesses habitats. Por outro lado, avifaunas “intermediárias” foram encontradas em algumas localidades; e no segundo capítulo, nós investigamos se a confluência com o Rio Branco, de água branca, muda a avifauna ao longo do próprio Rio Negro, que é o maior rio de água preta do mundo. Nós amostramos ilhas e margens ao longo do Rio Negro a montante e a jusante da confluência com o Rio Branco, e comparamos com amostragens no próprio Rio Branco. Essas amostragens revelaram uma miscelânea de avifaunas ao longo do Rio Negro, com maior riqueza no total abaixo da confluência. Além disso, a variação geral da avifauna na região foi correlacionada com distintos níveis de concentração de sedimentos na água (um parâmetro fundamental no tipo de água dos rios), o que indicou a importância desse fator para a ocorrência das aves nos ambientes alagáveis. Esse fenômeno de mistura de águas e avifaunas expressou os potenciais múltiplos papéis (isolamento, conexão e manutenção de habitats) das numerosas confluências de grandes rios amazônicos de diferentes tipos na distribuição da biodiversidade nesses habitats. Usando o tipo de água dos rios como ponto de partida, no terceiro capítulo, nós revisamos e analisamos as distribuições geográficas gerais das aves especialistas nos ambientes alagáveis. Dados inéditos de ocorrência de uma ampla e revisada lista dessas espécies especialistas confirmaram ao menos onze potenciais áreas de endemismo, essencialmente distintas das áreas coincidentes com grandes interflúvios, válidas para aves de terra-firme. Uma subdivisão da Amazônia em ao menos nove regiões, baseada na distribuição das aves especialistas nos ambientes alagáveis, é uma base alternativa para estudos da evolução e para conservação da biodiversidade. Em termos de conservação, a especialização das aves à micro-habitats específicos e geograficamente restritos indica alta vulnerabilidade. Embora grandes extensões dos ambientes alagáveis estejam sob proteção, as populações dessas espécies estão ameaçadas pelos planos de instalação de hidroelétricas em vários rios amazônicos,
que devem alterar a formação e a disponibilidade desses micro-habitats. Em síntese, essa tese consolida as especificidades biogeográficas dos habitats criados por rios na Amazônia. Padrões de distribuição das aves especialistas refletem amplamente as disparidades ecológicas e a complexa história recente de rios drenando diferentes regiões. Esses habitats oferecem oportunidades para uma melhor compreensão da riqueza e evolução da avifauna e da biodiversidade amazônica
Amazonian rainforest tree mortality driven by climate and functional traits
No full textTree mortality appears to be increasing in moist tropical forests 1 , with potentially important implications for global carbon and water cycles 2 . Little is known about the drivers of tree mortality in these diverse forests, partly because long-term data are lacking 3 . The relative importance of climatic factors and species functional traits as drivers of tropical tree mortality are evaluated using a unique dataset in which the survival of over 1,000 rainforest canopy trees from over 200 species has been monitored monthly over five decades in the Central Amazon. We found that drought, as well as heat, storms and extreme rainy years, increase tree mortality for at least two years after the climatic event. Specific functional groups (pioneers, softwoods and evergreens) had especially high mortality during extreme years. These results suggest that predicted climate change will lead to higher tree mortality rates, especially for short-lived species, which may result in faster carbon sequestration but lower carbon storage of tropical forests. © 2019, The Author(s), under exclusive licence to Springer Nature Limited
Mineral and organic fertilization affects Tetranychus urticae, pseudofruit production and leaf nutrient content in strawberry
No full textThe aim of this study was to evaluate the population of Tetranychus urticae Koch (Tetranychidae – twospotted spider mite - TSSM) submitted to mineral fertilizer or crescent doses of organic compost (OC) and find its correlation with nitrogen, potassium and phenolic compounds in strawberry leaves. Production were also evaluated. Plants were cultivated in pots, in a greenhouse, for two strawberry crop cycles. Treatments were: mineral fertilization; 0.5, 1.0, 1.5, 2.0 kg of OC plant−1, and control (no fertilization). Mobile TSSM forms on young leaves were evaluated. Production were evaluated by weighting ¾ red (mature) pseudofruits. Levels of nitrogen (N), potassium (K) and total phenolic content were also measured. Plants cultivated with mineral fertilization had higher TSSM populations and foliar nutrients and lower level of phenols. In the first experiment, a higher incidence of TSSM was observed on mineral fertilized plants and plants fertilized with higher dose of OC, compared to other treatments. In the second experiment, higher TSSM incidence was observed on mineral fertilizer plants compared to 1.0, 1.5 and 2.0 kg of OC plant−1. Positive correlation between foliar nitrogen and TSSM populations and negative correlation between phenolic compounds and TSSM populations were found. Mineral fertilized plants presented higher TSSM population than OC fertilized plants despite of similar levels of N in the leaves. Pseudofruits production were higher with 1.5 OC plant−1 fertilization on both cycles. © 2019, Springer Nature B.V
Acordo cooperativo entre a Samsung Eletrônica da Amazônia S.A, a Fundação Amazônica de Defesa da Biosfera - FDB e o INPA
No full textDesenvolvimento do projeto intitulado Projeto rede de monitoramento ambiental da bacia hidrográfica do Educandos-IET
Caracterization of A-Amylases complex produced by a Bradyrhizobium sp. isolated from an Amazonian soil
No full textWhy is Amazonia a 'source' of biodiversity? Climate-mediated dispersal and synchronous speciation across the Andes in an avian group (Tityrinae)
Get PDFAmazonia is a 'source' of biodiversity for other Neotropical ecosystems, but which conditions trigger in situ speciation and emigration is contentious. Three hypotheses for how communities have assembled include (1) a stochastic model wherein chance dispersal events lead to gradual emigration and species accumulation, (2) diversity-dependence wherein successful dispersal events decline through time due to ecological limits, and (3) barrier displacement wherein environmental change facilitates dispersal to other biomes via transient habitat corridors. We sequenced thousands of molecular markers for the Neotropical Tityrinae (Aves) and applied a novel filtering protocol to identify loci with high utility for dated phylogenomics. We used these loci to estimate divergence times and model Tityrinae's evolutionary history. We detected a prominent role for speciation driven by barriers including synchronous speciation across the Andes and found that dispersal increased toward the present. Because diversification was continuous but dispersal was non-random over time, we show that barrier displacement better explains Tityrinae's history than stochasticity or diversity-dependence. We propose that Amazonia is a source of biodiversity because (1) it is a relic of a biome that was once more extensive, (2) environmentally mediated corridors facilitated emigration and (3) constant diversification is attributed to a spatially heterogeneous landscape that is perpetually dynamic through time. © 2019 The Author(s)
