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The economic cost of losing native pollinator species for orchard production
No full textThe alarming loss of pollinator diversity world-wide can reduce the productivity of pollinator-dependent crops, which could have economic impacts. However, it is unclear to what extent the loss of a key native pollinator species affects crop production and farmer's profits. By experimentally manipulating the presence of colonies of a native bumblebee species Bombus pauloensis in eight apple orchards in South Argentina, we evaluated the impact of losing natural populations of a key native pollinator group on (a) crop yield, (b) pollination quality, and (c) farmer's profit. To do so, we performed a factorial experiment of pollinator exclusion (yes/no) and hand pollination (yes/no). Our results showed that biotic pollination increased ripe fruit set by 13% when compared to non-biotic pollination. Additionally, fruit set and the number of fruits per apple tree was reduced by less than a half in those orchards where bumblebees were absent, even when honeybees were present at high densities. Consequently, farmer's profit was 2.4-fold lower in farms lacking bumblebees than in farms hosting both pollinator species. The pollination experiment further suggested that the benefits of bumblebees could be mediated by improved pollen quality rather than quantity. Synthesis and applications. This study highlights the pervasive consequences of losing key pollinator functional groups, such as bumblebees, for apple production and local economies. Adopting pollinator-friendly practices such as minimizing the use of synthetic inputs or restoring/maintaining semi-natural habitats at farm and landscape scales, will have the double advantage of promoting biodiversity conservation, and increasing crop productivity and profitability for local farmers. Yet because the implementation of these practices can take time to deliver results, the management of native pollinator species can be a provisional complementary strategy to increase economic profitability of apple growers in the short term. © 2019 British Ecological Societ
Vegetative Propagation of Himatanthus sucuuba (Spruce ex Müll. Arg.) Woodson by Stem Cuttings
No full textThe efficiency of different methods to extract environmental DNA from freshwater samples of Solimões and Negro rivers.
No full textMolecular dynamics and binding energy analysis of Vatairea guianensis lectin: a new tool for cancer studies
No full textThe Tn antigen is an epitope containing N-acetyl-D-galactosamine present in the extracellular matrix of some carcinoma cells in humans, and it is often used as a biomarker. Lectins are proteins capable of binding to carbohydrates and can be used as a molecular tool to recognize antigens and to differentiate cancer cells from normal cells. In this context, the present work aimed to characterize the interaction of Vatairea guianensis seed lectin with N-acetyl-D-galactosamine and the Tn antigen by molecular dynamics and molecular mechanics/Poisson–Boltzmann solvent-accessible surface area analysis. This study revealed new interacting residues not previously identified in static analysis of the three-dimensional structures of Vatairea lectins, as well as the configuration taken by the carbohydrate recognition domain, as it interacts with each ligand. During the molecular dynamics simulations, Vatairea guianensis lectin was able to bind stably to Tn antigen, which, as seen previously for other lectins, enables its use in cancer research, diagnosis, and therapy. This work further demonstrates the efficiency of bioinformatics in lectinology. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature
New karyotype records for the genus Proechimys (Rodentia: Echimyidae) from Brazilian Amazonia
No full textStructure of the rheophilic ichthyofauna of the Xingu river, Brazilian Amazon: environmental, spatial and temporal effects on the species distribution pattern
No full textRapids and waterfalls are environments that have extreme and peculiar environmental characteristics when compared to other river stretches. These sites harbor fish species with unique ecological characteristics, with remarkable morphological and behavioral specializations related to the life in structurally complex environments with fast and turbulent waters. In this study we evaluated the structure of the ichthyofauna in the rapids of Xingu River, aiming to a better understanding of the fish assemblage composition and its spatial and temporal variations. We recorded 160 fish species in the rapids, belonging to 97 genera, 25 families and seven orders. Characiformes presented the highest number of families, and Siluriformes the highest number of species. Fifty-two species are endemic to the Xingu River, 11 species are officially considered under some degree of extinction risk, and not all species are protected by the large mosaic of conservation units in the Xingu River basin. The stretch corresponding to the Volta Grande do Xingu harbors the highest diversity of rheophilic fishes along the analyzed stretch of the river, and some species apparently occur only in that stretch. The Volta Grande do Xingu is one of the largest continuous rapids in the world, but the structure of the fish assemblages of this region varies both seasonaly and regarding local habitat characteristics. The largest variations were observed between the main channel rapids of the Xingu and Bacajá rivers, and between the flooding period compared to the receding and dought periods. Although some species occurred in just a few sites or were more abundant in some periods of the hydrologic cycle, several species occurred in all sampling sites and periods, highlighting the possible role of habitat connectivity along the rapids continuum. However, additional analyses of the distribution and abundance of Loricariidae species in Volta Grande evidenced the role of spatial factors acting at different distance scales, which together with the local structure of microhabitats are essential for the maintenance of the loricariid diversity. Food availability did not have a major influence on the structure of Loricariid assemblages, apparently due to the high availability of food items from epilithic and benthic macroinvertebrates. Despite the biological importance of waterfalls and rapids environments, especially those of Volta Grande, a hydroelectric megadam is installed in the region and a huge gold mining project is being licensed, threatening one of the world's most spectacular river rapids.As corredeiras e cachoeiras são ambientes que apresentam características ambientais extremas e diferentes da maior parte do curso dos rios. Esses locais abrigam espécies de peixes com características ecológicas peculiares, com especializações morfológicas e comportamentais relacionados à vida em ambientes estruturalmente complexos e com águas rápidas e turbulentas. Neste estudo avaliamos a estrutura da ictiofauna associada aos ambientes de corredeiras do rio Xingu, buscando um melhor entendimento da composição das assembleias de peixes e suas variações espaciais e temporais. Foram registradas 160 espécies de peixes abrigando as corredeiras do rio Xingu, pertencentes a 97 gêneros, 25 famílias e sete ordens. Characiformes apresentou o maior número de famílias e Siluriformes o maior número de espécies. Cinquenta e duas espécies são endêmicas do rio Xingu, 11 espécies são oficialmente consideradas sob algum grau de ameaça de extinção, e nem todas as espécies estão protegidas pelo grande mosaico de unidades de conservação presentes na bacia do rio Xingu. O trecho da Volta Grande do rio Xingu apresenta a maior diversidade de espécies de peixes reofílicos, e algumas espécies ocorrem apenas naquele trecho. A Volta Grande é um dos maiores contínuos de corredeiras do mundo, mas a estrutura das assembleias de peixes dessa região apresenta diferenças em relação aos períodos sazonais e em função das características locais dos sítios de amostragem. As maiores variações foram observada entre as corredeiras do canal principal do rio Xingu e as corredeiras do rio Bacajá, e entre os períodos de enchente em relação à vazante e seca. Embora algumas espécies tenham ocorrido em apenas alguns sítios ou tenham sido mais abundantes em alguns períodos, a Volta Grande apresenta um conjunto de espécies que ocorrem em todos os sítios e períodos, evidenciando o possível papel da conectividade de hábitats ao longo do contínuo de corredeiras. Uma análise mais aprofundada da distribuição e abundância de espécies de Loricariidae na Volta Grande demonstrou que fatores espaciais em diferentes escalas de distância, bem como a estrutura local de micro-hábitats são essenciais para a manutenção das espécies dessa família. Disponibilidade de alimento não apresentou grande influência na estruturação das assembleias de Loricariídeos, aparentemente devido à alta disponibilidade de itens alimentares do epilíton e de macroinvertebrados bentônicos. Apesar da importância biológica dos ambientes de cachoeiras e corredeiras, em especial as da Volta Grande, um megaprojeto hidrelétrico está sendo finalizado nessa região e há projetos de mineração de ouro sendo licenciados, colocando em risco uma das áreas de corredeiras mais excepcionais do mundo
TRY plant trait database – enhanced coverage and open access
Get PDFPlant traits—the morphological, anatomical, physiological, biochemical and phenological characteristics of plants—determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits—almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives. © 2019 The Authors. Global Change Biology published by John Wiley & Sons Lt
