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Loneura Navás (Psocodea: Psocomorpha: Ptiloneuridae): New species from Brazil, and description of the female of Loneura maracaensis Garcia Aldrete, with a checklist of all known species of the genus
No full textA new Loneura species from the Brazilian state of Bahia (Loneura baiana n. sp.), is here described and illustrated. It is assignable to a species group of the genus but not to any of its subgroups. The previously unknown female of Loneura maracaensis Garcia Aldrete is described and illustrated, comments on variation in the fore-and hindwing venation of two male specimens of this species are included. Information on sexes known and distribution is included for all known species of Loneura. © 2019 Magnolia Press
Erosion of phylogenetic diversity in Neotropical bat assemblages: findings from a whole-ecosystem fragmentation experiment
Get PDFThe traditional focus on taxonomic diversity metrics for investigating species responses to habitat loss and fragmentation has limited our understanding of how biodiversity is impacted by habitat modification. This is particularly true for taxonomic groups such as bats which exhibit species-specific responses. Here, we investigate phylogenetic alpha and beta diversity of Neotropical bat assemblages across two environmental gradients, one in habitat quality and one in habitat amount. We surveyed bats in 39 sites located across a whole-ecosystem fragmentation experiment in the Brazilian Amazon, representing a gradient of habitat quality (interior-edge-matrix, hereafter IEM) in both continuous forest and forest fragments of different sizes (1, 10, and 100 ha; forest size gradient). For each habitat category, we quantified alpha and beta phylogenetic diversity, then used linear mixed-effects models and cluster analysis to explore how forest area and IEM gradient affect phylogenetic diversity. We found that the secondary forest matrix harboured significantly lower total evolutionary history compared to the fragment interiors, especially the matrix near the 1 ha fragments, containing bat assemblages with more closely related species. Forest fragments ≥ 10 ha had levels of phylogenetic richness similar to continuous forest, suggesting that large fragments retain considerable levels of evolutionary history. The edge and matrix adjacent to large fragments tend to have closely related lineages nonetheless, suggesting phylogenetic homogenization in these IEM gradient categories. Thus, despite the high mobility of bats, fragmentation still induces considerable levels of erosion of phylogenetic diversity, suggesting that the full amount of evolutionary history might not be able to persist in present-day human-modified landscapes. © 2019, The Author(s)
Phytosociology of native species in the understory of a corymbia citriodora stand in Espírito Santo State, Brazil
Get PDFThis study is based on the hypothesis that unmanaged plantations of commercial species do not prevent understory colonization by native species. The research aimed to describe the floristic composition and structure of native arboreal species in the understory of a Corymbia citriodora stand. To this end, 112 plots (10 × 10 m; 1.12 ha) were installed. Six hundred native tree individuals distributed in 54 species, 44 genera, and 20 families were recorded. The regeneration diversity and evenness indices were 3.23 and 0.81, respectively. Native regeneration of C. citriodora understory shows features typical of semideciduous seasonal forests and seems to be at the early stage of regeneration. Results suggest that C. citriodora stands do not prevent understory colonization by native species. © 2019 FLORAM
Thirty years after Balbina Dam: Diversity and floristic composition of the downstream floodplain forest, Central Amazon, Brazil
No full textThe construction of hydroelectric dams causes changes in the diversity and floristic composition of floodplain forests due to the irregularity of the hydrological regime in rivers downstream from the dams. In the Amazon Basin, plans for the construction of dams are threatening the igapós, forests flooded by blackwater rivers. In these floodplains, the distribution of tree species is synchronized with periodic flood events of the topographic gradient. Previous studies on the Balbina Dam show an altered flood pulse downstream. This work discusses the potential long-term impacts on the diversity and floristic composition of an igapó downstream of the dam (Uatumã River) and compares it with an area unaffected by the dam (Abacate River). An evaluation of the vegetation strata—adults, saplings, and seedlings—showed that for all strata, diversity was greater in the high igapó (higher topographies) in the Uatumã area. This may be due to the near-total absence of flooding in the high igapó and to the extent of flooding in the low igapó (low topographies). Thus, in the Uatumã area, seeds of species typical of flooded areas cannot reach the high igapó by water and, thus, tend to be replaced by upland forest species (mainly seedlings). In the low igapó, the typical species have difficulty establishing. Therefore, the Uatumã vegetation forms two different communities, which does not occur in the Abacate area. These effects of the dam led to irreversible changes in the diversity and floristic composition across all strata throughout the entire topography in the downstream region. © 2019 John Wiley & Sons, Ltd
Hydrogeological Characteristic and the Vulnerability Degree of the Aquifers from Municipality of Abaetetuba, Pará - Brazil
No full textEdaphic Factors and Flooding Periodicity Determining Forest Types in a Topographic Gradient in the Northern Brazilian Amazonia
No full textAVALIAÇÃO DE RESTO-INGESTÃO DA ALIMENTAÇÃO ESCOLAR DE DUAS ESCOLAS PÚBLICAS DE TEMPO INTEGRAL DE MANAUS ? AM
No full textAlien spiders: First record of loxosceles gaucho Gertsch, 1967 (Araneae: Sicariidae) in the Amazon region, Brazil
Get PDFWe present the first record for Loxosceles gaucho Gertsch, 1967 in the Amazonian region of Brazil. Four males, fifteen females and forty-nine immatures were collected in different places in Manaus, Amazonas, Brazil. This is the third species of Loxosceles reported in the Amazon region along with L. amazonica Gertsch, 1967, and L. similis Moenkhaus, 1898. This is the first record of an invasive species of a venomous animal in the state of Amazonas, Brazil, which is noteworthy due to its synanthropic habit, which increases the risk to the local population. © 2019, Universidade de Sao Paulo. All rights reserved
Integração de dados de campo e sensoriamento remoto no estudo do fluxo de água e matéria no Arquipélago de Anavilhanas, Rio Negro - Amazonas, Brasil
Get PDFRio Negro is the sixth largest river in the world in water volume and the largest black water ecosystem in the Amazon basin. Its lower course is a unique and important region with hundreds of islands, lakes and channels, and include the second largest fluvial archipelago in the world, called Anavilhanas. This whole region is a global biodiversity hotspot, it supports the livelihood of hundreds of local communities and is a destination for ecotourists. Despite its importance, little is known about the water properties of this region and how human activities, such as the construction of dams, impact its properties and functioning of this ecosystem. The Rio Negro basin has the lowest density of hydrological monitoring stations among other large Amazon rivers. On the other hand, advances in remote sensing technology can fill gaps in hydrological and water quality data. Here I explore how we can use remote sensing data and methods to better understand the dynamic between water, matter and the use of natural resources in this region. Specifically, I aimed at understanding the spatial and temporal variability of water flows, suspended sediments concentration (SSC) and dissolved organic carbon (DOC) in the lower Rio Negro, especially in the channels of the Anavilhanas archipelago, through data integration hydrological and remote sensing data (field radiometry, Terra/Aqua, Sentinel-1, Sentinel-2 and Sentinel-3 satellites). The results indicate that in the 2016-2017 hydrological year the average SSC in Rio Negro was 3.06 mg L-1 and the average DOC concentration was 9.60 mg L-1. Suspended sediment flow between 1 and 9 million tons per year and flow of dissolved organic carbon in the order of 11 million tons per year were estimated for the Rio Negro basin. The flow of dissolved organic carbon was directly related to the Rio Negro liquid discharge, with higher and lower values occurring in the periods of high and low waters, respectively. The peak of discharge of suspended sediment near Manaus occurred in September, with a lag of two months in relation to that observed upstream of the Anavilhanas archipelago. It was identified retention of 60% of suspended sediment from the Rio Negro reaching the archipelago. Due to the high amount of DOC and low SSC load, Rio Negro has very low values of reflected energy (Rrs <0.018 sr-1 in the visible) and great light absorption (≈ 8.00 m-1 at 440 nm). The variability of the reflected energy throughout the hydrological year was controlled by the inflow of suspended sediment from the Rio Branco, (the major tributary of the Rio Negro basin) that changed the optical properties of the Rio Negro in Anavilhanas. Evaluations of multispectral satellites to estimate SSC in Anavilhanas showed better results with the red band (650–690 nm). Empirical models show that the green/red band ratio can be used as an indicator of the dissolved organic carbon of the Rio Negro. The hydrogeomorphological scenario characterized suggests a slow and continuous process of retention of the suspended solid load in Anavilhanas, with a sedimentation rate approximately eight times lower than those estimated during the archipelago's formation period. I conclude that the Anavilhanas fluvial system acts as a water reservoir and suspended sediment sink in the lower course of the Rio Negro, mainly the period of greatest influence of the Rio Solimões backwater effect. This study presents data on the lower course region of Rio Negro that can be used in future scientific studies and decision-making, for example to asses extreme weather events in the region or the impact the construction of Bem Querer hydroelectric power plant in the Rio Branco.O Rio Negro é considerado o sexto maior rio do mundo em volume de água e o maior ecossistema de águas pretas da bacia Amazônica. Em seu baixo curso destacam-se na paisagem centenas de ilhas, lagos e canais do arquipélago de Anavilhanas, cujo nível de base é controlado pelo Rio Solimões. O barramento hidráulico do Rio Solimões sobre o Rio Negro influencia seu regime hidrológico, o transporte de sedimento suspenso e de carbono orgânico dissolvido. Para um melhor entendimento das relações entre água, matéria e o uso dos recursos naturais na região são necessários dados e o desenvolvimento de modelos apropriados. No entanto, a bacia do Rio Negro possui a menor densidade de estações de monitoramento hidrológico em comparação aos grandes rios Amazônicos. Por outro lado, avanços na tecnologia de sensoriamento remoto têm contribuído para superar lacunas de dados hidrológicos e da qualidade d’água. Esta pesquisa teve como objetivo entender a variabilidade espacial e temporal dos fluxos de água, de concentração de sedimentos suspensos (CSS) e do carbono orgânico dissolvido (COD) no baixo Rio Negro, especialmente nos canais do arquipélago de Anavilhanas, através da integração de dados hidrológicos, da qualidade d’água com dados de sensoriamento remoto (radiometria de campo, dados dos satélites Terra/Aqua, Sentinel-1, Sentinel-2 e Sentinel-3). Resultados obtidos indicam que no ano hidrológico 2016-2017 a CSS média no Rio Negro foi de 3,06 mg L-1 e a concentração média do COD foi de 9,60 mg L-1. Estimou-se para a bacia do Rio Negro um fluxo de sedimento suspenso entre 1 e 9 milhões de toneladas por ano e um fluxo de carbono orgânico dissolvido da ordem de 11 milhões de toneladas por ano. O fluxo de carbono orgânico dissolvido apresentou relação direita com o regime de descarga líquida do Rio Negro, com maiores e menores valores ocorrendo nos períodos de cheia e seca, respectivamente. O pico de descarga do sedimento suspenso próximo de Manaus ocorre em setembro, com defasagem de dois meses em relação ao observado a montante do arquipélago de Anavilhanas. Identificou-se retenção de 60% de sedimento suspenso do Rio Negro que aporta no arquipélago. Em função da elevada quantidade de COD e baixa carga de CSS o Rio Negro apresenta valores muito baixos da energia refletida (Rrs < 0,018 sr-1 no visível) e grande absorção da luz (≈ 8,00 m-1 em 440 nm). A variabilidade da energia refletida ao longo do ano hidrológico é controlada principalmente pelo aporte de sedimento suspenso do Rio Branco que altera as propriedades ópticas do Rio Negro em Anavilhanas. Avaliações de satélites multiespectrais para estimar a CSS em Anavilhanas mostraram melhores resultados com a banda do vermelho (650–690 nm). Modelos empíricos mostram que a razão de bandas verde/vermelho pode ser utilizada como indicador do carbono orgânico dissolvido do Rio Negro. O cenário hidrogeomorfológico caracterizado sugere um lento e contínuo processo de retenção da carga sólida suspensa em Anavilhanas, com uma taxa de sedimentação aproximadamente oito vezes menor que as estimadas no período de formação do arquipélago. Conclui-se que o sistema fluvial de Anavilhanas atua como reservatório de água e sumidouro de sedimento suspenso no baixo curso do Rio Negro, principalmente o período de maior influência do barramento hidráulico do Rio Solimões. Este estudo da hidrologia do arquipélago de Anavilhanas apresenta dados que podem servir de linha de base para avaliar os impactos de eventos climáticos extremos na região ou em virtude do represamento do Rio Branco devido à construção da hidrelétrica de Bem Querer