Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 575
Filtrar
1.
Microbiome ; 9(1): 24, 2021 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-33482922

RESUMO

BACKGROUND: Freshwater ecosystems are inhabited by members of cosmopolitan bacterioplankton lineages despite the disconnected nature of these habitats. The lineages are delineated based on > 97% 16S rRNA gene sequence similarity, but their intra-lineage microdiversity and phylogeography, which are key to understanding the eco-evolutional processes behind their ubiquity, remain unresolved. Here, we applied long-read amplicon sequencing targeting nearly full-length 16S rRNA genes and the adjacent ribosomal internal transcribed spacer sequences to reveal the intra-lineage diversities of pelagic bacterioplankton assemblages in 11 deep freshwater lakes in Japan and Europe. RESULTS: Our single nucleotide-resolved analysis, which was validated using shotgun metagenomic sequencing, uncovered 7-101 amplicon sequence variants for each of the 11 predominant bacterial lineages and demonstrated sympatric, allopatric, and temporal microdiversities that could not be resolved through conventional approaches. Clusters of samples with similar intra-lineage population compositions were identified, which consistently supported genetic isolation between Japan and Europe. At a regional scale (up to hundreds of kilometers), dispersal between lakes was unlikely to be a limiting factor, and environmental factors or genetic drift were potential determinants of population composition. The extent of microdiversification varied among lineages, suggesting that highly diversified lineages (e.g., Iluma-A2 and acI-A1) achieve their ubiquity by containing a consortium of genotypes specific to each habitat, while less diversified lineages (e.g., CL500-11) may be ubiquitous due to a small number of widespread genotypes. The lowest extent of intra-lineage diversification was observed among the dominant hypolimnion-specific lineage (CL500-11), suggesting that their dispersal among lakes is not limited despite the hypolimnion being a more isolated habitat than the epilimnion. CONCLUSIONS: Our novel approach complemented the limited resolution of short-read amplicon sequencing and limited sensitivity of the metagenome assembly-based approach, and highlighted the complex ecological processes underlying the ubiquity of freshwater bacterioplankton lineages. To fully exploit the performance of the method, its relatively low read throughput is the major bottleneck to be overcome in the future. Video abstract.


Assuntos
Biodiversidade , Água Doce , Filogeografia , Plâncton/genética , Plâncton/isolamento & purificação , Análise de Sequência de DNA/métodos , Organismos Aquáticos/classificação , Organismos Aquáticos/genética , Organismos Aquáticos/isolamento & purificação , Europa (Continente) , Japão , Filogenia , Plâncton/classificação , RNA Ribossômico 16S/genética
2.
PLoS One ; 16(1): e0244598, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33395693

RESUMO

Although aquatic macroinvertebrates and freshwater fishes are important indicators for freshwater quality assessments, the morphological identification to species-level is often impossible and thus especially in many invertebrate taxa not mandatory during Water Framework Directive monitoring, a pragmatism that potentially leads to information loss. Here, we focus on the freshwater fauna of the River Sieg (Germany) to test congruence and additional value in taxa detection and taxonomic resolution of DNA barcoding vs. morphology-based identification in monitoring routines. Prior generated morphological identifications of juvenile fishes and aquatic macroinvertebrates were directly compared to species assignments using the identification engine of the Barcode of Life Data System. In 18% of the invertebrates morphology allowed only assignments to higher systematic entities, but DNA barcoding lead to species-level assignment. Dissimilarities between the two approaches occurred in 7% of the invertebrates and in 1% of the fishes. The 18 fish species were assigned to 20 molecular barcode index numbers, the 104 aquatic invertebrate taxa to 113 molecular entities. Although the cost-benefit analysis of both methods showed that DNA barcoding is still more expensive (5.30-8.60€ per sample) and time consuming (12.5h), the results emphasize the potential to increase taxonomic resolution and gain a more complete profile of biodiversity, especially in invertebrates. The provided reference DNA barcodes help building the foundation for metabarcoding approaches, which provide faster sample processing and more cost-efficient ecological status determination.


Assuntos
Organismos Aquáticos/genética , Código de Barras de DNA Taxonômico , Peixes/genética , Invertebrados/genética , Animais , Organismos Aquáticos/classificação , Biodiversidade , Peixes/classificação , Alemanha , Invertebrados/classificação , Rios
3.
PLoS One ; 16(1): e0241095, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33503057

RESUMO

Sponges produce distinct fatty acids (FAs) that (potentially) can be used as chemotaxonomic and ecological biomarkers to study endosymbiont-host interactions and the functional ecology of sponges. Here, we present FA profiles of five common habitat-building deep-sea sponges (class Demospongiae, order Tetractinellida), which are classified as high microbial abundance (HMA) species. Geodia hentscheli, G. parva, G. atlantica, G. barretti, and Stelletta rhaphidiophora were collected from boreal and Arctic sponge grounds in the North-Atlantic Ocean. Bacterial FAs dominated in all five species and particularly isomeric mixtures of mid-chain branched FAs (MBFAs, 8- and 9-Me-C16:0 and 10- and 11-Me-C18:0) were found in high abundance (together ≥ 20% of total FAs) aside more common bacterial markers. In addition, the sponges produced long-chain linear, mid- and a(i)-branched unsaturated FAs (LCFAs) with a chain length of 24‒28 C atoms and had predominantly the typical Δ5,9 unsaturation, although the Δ9,19 and (yet undescribed) Δ11,21 unsaturations were also identified. G. parva and S. rhaphidiophora each produced distinct LCFAs, while G. atlantica, G. barretti, and G. hentscheli produced similar LCFAs, but in different ratios. The different bacterial precursors varied in carbon isotopic composition (δ13C), with MBFAs being more enriched compared to other bacterial (linear and a(i)-branched) FAs. We propose biosynthetic pathways for different LCFAs from their bacterial precursors, that are consistent with small isotopic differences found in LCFAs. Indeed, FA profiles of deep-sea sponges can serve as chemotaxonomic markers and support the concept that sponges acquire building blocks from their endosymbiotic bacteria.


Assuntos
Organismos Aquáticos , Ácidos Graxos Insaturados/metabolismo , Geodia/metabolismo , Poríferos/microbiologia , Animais , Organismos Aquáticos/classificação , Organismos Aquáticos/metabolismo , Organismos Aquáticos/microbiologia
4.
Sci Rep ; 10(1): 21846, 2020 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-33318512

RESUMO

Three strains of novel bacteria were isolated from oil-contaminated sediment from the Arabian Gulf (Brevibacillus brevis T2C2008, Proteus mirabilis T2A12001, and Rhodococcus quinshengi TA13008). The isolated strains were tested for their degrading efficacy of low and high molecular hydrocarbon (naphthalene and pyrene). The efficacy of the two-hydrocarbon degradation by the isolates bacterial was determined at a temperature of 25 °C and 37 °C and pH of 5.0 and 9.0. In inoculated media at 37 °C, Rhodococcus qinshengi fully metabolized naphthalene and degrade 56% of pyrene. Brevibacillus brevis break down over 80% of naphthalene at room temperatures (25 °C). However, it was found that P. mirabilis and R. qinshengi biodegraded nearly 94% of naphthalene in the incubated media. The capacity for pyrene and naphthalene degradation in varying pH and temperature conditions was shown to be significant in Rhodococcus qinshengi because of its mineralization exceeding 50% across the tested pH and temperature. This implies that the isolated strains are ideal for biodegradation of contaminated sediment with naphthalene and pyrene.


Assuntos
Organismos Aquáticos , Bactérias , Sedimentos Geológicos/microbiologia , Naftalenos/metabolismo , Poluição por Petróleo , Organismos Aquáticos/classificação , Organismos Aquáticos/isolamento & purificação , Organismos Aquáticos/metabolismo , Bactérias/classificação , Bactérias/isolamento & purificação , Bactérias/metabolismo , Biodegradação Ambiental , Oceanos e Mares
5.
PLoS One ; 15(12): e0244323, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33370342

RESUMO

The Southeast Pacific comprises two Large Marine Ecosystems, the Pacific Central-American Coastal and the Humboldt Current System; and is one of the less well known in the tropical subregions in terms of biodiversity. To address this, we compared DNA barcoding repositories with the marine biodiversity species for the Southeast Pacific. We obtained a checklist of marine species in the Southeast Pacific (i.e. Colombia, Ecuador, Chile, and Peru) from the Ocean Biodiversity Information System (OBIS) database and compared it with species available at the Barcoding of Life Data System (BOLD) repository. Of the 5504 species records retrieved from OBIS, 42% of them had at least one registered specimen in BOLD (including specimens around the world); however, only 4.5% of records corresponded to publicly available DNA barcodes including specimens collected from a Southeast Pacific country. The low representation of barcoded species does not vary much across the different taxonomic groups or within countries, but we observed an asymmetric distribution of DNA barcoding records for taxonomic groups along the coast, being more abundant for the Humboldt Current System than the Pacific Central-American Coastal. We observed high-level of barcode records with Barcode Index Number (BIN) incongruences, particularly for fishes (Actinopterygii = 30.27% and Elasmobranchii = 24.71%), reflecting taxonomic uncertainties for fishes, whereas for Invertebrates and Mammalia more than 85% of records were classified as data deficient or inadequate procedure for DNA barcoding. DNA barcoding is a powerful tool to study biodiversity, with a great potential to increase the knowledge of the Southeast Pacific marine biodiversity. Our results highlight the critical need for increasing taxonomic sampling effort, the number of trained taxonomic specialists, laboratory facilities, scientific collections, and genetic reference libraries.


Assuntos
Organismos Aquáticos/classificação , Organismos Aquáticos/genética , Código de Barras de DNA Taxonômico/métodos , Animais , Biodiversidade , DNA , Ecossistema , Peixes/classificação , Peixes/genética , Biblioteca Gênica , Invertebrados/classificação , Invertebrados/genética , Oceano Pacífico/epidemiologia , Filogenia , América do Sul
6.
Nature ; 585(7826): 557-562, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32939093

RESUMO

Climate and physiology shape biogeography, yet the range limits of species can rarely be ascribed to the quantitative traits of organisms1-3. Here we evaluate whether the geographical range boundaries of species coincide with ecophysiological limits to acquisition of aerobic energy4 for a global cross-section of the biodiversity of marine animals. We observe a tight correlation between the metabolic rate and the efficacy of oxygen supply, and between the temperature sensitivities of these traits, which suggests that marine animals are under strong selection for the tolerance of low O2 (hypoxia)5. The breadth of the resulting physiological tolerances of marine animals predicts a variety of geographical niches-from the tropics to high latitudes and from shallow to deep water-which better align with species distributions than do models based on either temperature or oxygen alone. For all studied species, thermal and hypoxic limits are substantially reduced by the energetic demands of ecological activity, a trait that varies similarly among marine and terrestrial taxa. Active temperature-dependent hypoxia thus links the biogeography of diverse marine species to fundamental energetic requirements that are shared across the animal kingdom.


Assuntos
Organismos Aquáticos/classificação , Organismos Aquáticos/metabolismo , Ecossistema , Filogeografia , Aerobiose , Animais , Organismos Aquáticos/crescimento & desenvolvimento , Metabolismo Basal , Aves/metabolismo , Peso Corporal , Hipóxia/metabolismo , Hipóxia/veterinária , Mamíferos/metabolismo , Oxigênio/metabolismo , Répteis/metabolismo , Especificidade da Espécie , Temperatura
7.
PLoS One ; 15(9): e0235588, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32946457

RESUMO

Data on the historical change of the Transbaikalian malacofauna in the Neopleistocene and Holocene is presented. Aquatic mollusc shells from archaeological excavations of the ancient settlements dating from the Neolithic period to Medieval and also from a drill hole of the Neopleistocene alluvial deposits were collected. In total eight species of bivalve molluscs from the families Margaritiferidae, Unionidae, Lymnocardiidae, Glycymerididae [marine], and two gastropod species from families Viviparidae and Planorbidae were identified. These species were aged using radiocarbon dating. It was found that the species ranged in age from more than 50.000 to 2.080-1.210 years BP. Five species inhabited the Transbaikal region which are locally extirpated today. Their disjunctive ranges in the past included southern Europe and Western and Eastern Siberia to Transbaikalia and in the east to Far East and Primorye Territory of Russia. A remarkable finding is that of the bivalve genus Monodacna, which was found very far from its native range, the Ponto-Caspian region. The time of existence and extirpation of the thermophilic species of genera Monodacna, Planorbis, Lanceolaria and Amuropaludina corresponds to cycles of the warming and cooling in Pleistocene and Holocene according to regional climate chronological scales. These species can be used as palaeoclimate indicators. Change of the regional malacofaunal species composition is connected with the natural climatochron cycles in the Pleistocene and Holocene resulting in evidence for succession. In the course of this succession, these stenothermal species became extirpated on a regional level, decreasing their global ranges.


Assuntos
Distribuição Animal , Organismos Aquáticos/fisiologia , Biodiversidade , Ecologia/métodos , Moluscos/fisiologia , Exoesqueleto/química , Animais , Organismos Aquáticos/química , Organismos Aquáticos/classificação , Arqueologia , Europa (Continente) , Extremo Oriente , Fósseis , Água Doce , Geografia , História Antiga , Moluscos/química , Moluscos/classificação , Datação Radiométrica , Sibéria
8.
Biomolecules ; 10(7)2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32645994

RESUMO

Oceans cover more than 70 percent of the surface of our planet and are characterized by huge taxonomic and chemical diversity of marine organisms. Several studies have shown that marine organisms produce a variety of compounds, derived from primary or secondary metabolism, which may have antiviral activities. In particular, certain marine metabolites are active towards a plethora of viruses. Multiple mechanisms of action have been found, as well as different targets. This review gives an overview of the marine-derived compounds discovered in the last 10 years. Even if marine organisms produce a wide variety of different compounds, there is only one compound available on the market, Ara-A, and only another one is in phase I clinical trials, named Griffithsin. The recent pandemic emergency caused by SARS-CoV-2, also known as COVID-19, highlights the need to further invest in this field, in order to shed light on marine compound potentiality and discover new drugs from the sea.


Assuntos
Antivirais/química , Organismos Aquáticos/química , Produtos Biológicos/química , Antivirais/farmacologia , Organismos Aquáticos/classificação , Produtos Biológicos/farmacologia , Coronaviridae/efeitos dos fármacos
9.
Eur J Protistol ; 75: 125721, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32575029

RESUMO

The dark ocean and the underlying deep seafloor together represent the largest environment on this planet, comprising about 80% of the oceanic volume and covering more than two-thirds of the Earth's surface, as well as hosting a major part of the total biosphere. Emerging evidence suggests that these vast pelagic and benthic habitats play a major role in ocean biogeochemistry and represent an "untapped reservoir" of high genetic and metabolic microbial diversity. Due to its huge volume, the water column of the dark ocean is the largest reservoir of organic carbon in the biosphere and likely plays a major role in the global carbon budget. The dark ocean and the seafloor beneath it are also home to a largely enigmatic food web comprising little-known and sometimes spectacular organisms, mainly prokaryotes and protists. This review considers the globally important role of pelagic and benthic protists across all protistan size classes in the deep-sea realm, with a focus on their taxonomy, diversity, and physiological properties, including their role in deep microbial food webs. We argue that, given the important contribution that protists must make to deep-sea biodiversity and ecosystem processes, they should not be overlooked in biological studies of the deep ocean.


Assuntos
Organismos Aquáticos/classificação , Eucariotos/classificação , Foraminíferos/classificação , Animais , Organismos Aquáticos/fisiologia , Eucariotos/fisiologia , Foraminíferos/fisiologia , Oceanos e Mares
10.
Eur J Protistol ; 75: 125701, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32599513

RESUMO

Korotnevella (Amoebozoa, Dactylopodida) is a genus of naked lobose amoebae with a dactylopodial morphotype. The cell membrane of these amoebae is covered with a monolayer of scales. The structure and size of scales are considered as species-specific features. Here, we describe a new marine species, Korotnevella mutabilis n. sp., isolated from the bottom sediment sample of Nivå Bay (Baltic Sea, The Sound) and studied with light and electron microscopy as well as with molecular phylogenetic analysis. This species has a number of morphological similarities with Korotnevella monacantholepis, such as size of the cell, L/B ratio, the nucleus structure and the type of a biotope from which both species were isolated. At the same time, Korotnevella mutabilis n. sp. differs from K. monacantholepis in the structure of basket-shaped scales: Korotnevella mutabilis n. sp. has an enclosed hammock-shaped latticework basket and up to two spines while K. monacantholepis has an opened two-row latticework basket and never has two spines. According to molecular phylogenetic analyses based on the sequences of the mitochondrial COI gene, Korotnevella mutabilis n. sp. is a distinct species, highly divergent from other Korotnevella species.


Assuntos
Amebozoários/classificação , Organismos Aquáticos/classificação , Amebozoários/genética , Amebozoários/ultraestrutura , Animais , Organismos Aquáticos/genética , Organismos Aquáticos/ultraestrutura , Complexo IV da Cadeia de Transporte de Elétrons/genética , Microscopia Eletrônica , Oceanos e Mares , Filogenia , Especificidade da Espécie
11.
An Acad Bras Cienc ; 92(2): e20181096, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32520216

RESUMO

The present study describes the community diversity and gives a seasonal distribution of an intertidal macroalgal assemblage at Prainha Beach, Arraial do Cabo City in Rio de Janeiro state, Brazil. Sampling was performed during four seasons of a 1-year period. Organisms were sampled and photographed using photoquadrats to quantify relative coverage. Ninety-six taxa of macroalgae were registered, including 23 chlorophytes, 19 ochrophytes, and 54 rhodophytes, while three barnacles, seven mollusks, one isopod, and one polychaete were recorded among the zoobenthos. In the upper intertidal zone, the coverage was frequently dominated by invertebrates. Macroalgae always dominated the middle and lower zones, covering almost 100 % in both zones. The highest values of species diversity (H'), richness (S), and turnover rates were found during the transition from spring to summer, which coincided with the upwelling period. A comparison with the 1980's flora revealed that the major changes in the macroalgal assemblage were among species belonging to the same genera, unless new additions were provided. The combination of photoquadrats and minimally destructive sampling allowed a detailed description of the composition and structural characteristics of the intertidal zone, a methodology that should be applied to study protected marine areas.


Assuntos
Organismos Aquáticos/classificação , Biodiversidade , Animais , Biomassa , Brasil , Estações do Ano
12.
Mol Phylogenet Evol ; 149: 106852, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32417496

RESUMO

The polychaetes of the family Cirratulidae (Annelida) are common inhabitants in continental shelf benthic environments and considered an important group of organisms in environmental monitoring surveys. The family represents a taxonomic and systematic challenge, as monophyly of genera and evolutionary relationships within the family remain to be explored in a proper phylogenetic framework. Bitentaculate cirratulids, especially the genus Chaetozone, form one of the most species-diverse group of polychaetes worldwide. In this study, we aimed at evaluating the species diversity of the genus Chaetozonein benthic environments in the North East Atlantic by molecular means. We tested whether traditional morphological diagnostic characters are able to discriminate between the species hypothesis after species delimitation analyses, and assessed monophyly of the genera involved. Two DNA markers were sequenced from about 200 specimens belonging to Chaetozone, Aphelochaeta, Dodecaceria, Cirriformia and Cirratulus - the universal mitochondrial barcoding region COI, and the D1-D2 regions of the nuclear 28S rRNA - and analyzed with Bayesian inference, Maximum Likelihood and the species delimitation methods mPTP and GMYC. The first phylogeny of the family Cirratulidae is inferred and the genera Chaetozone, Dodecaceria and Cirratulus are recovered monophyletic. A total of 14 clusters of sequences - corresponding to species of Chaetozone - were found in the study area, and only one of them is here referred to a nominal species, Chaetozone setosa. Our results reveal several species complexes in the genus Chaetozone, that some of these independent lineages are unnamed and undescribed, and that morphological diagnostic features are in most cases unable to discriminate between the most similar species.


Assuntos
Anelídeos/classificação , Organismos Aquáticos/classificação , Biodiversidade , Animais , Anelídeos/anatomia & histologia , Oceano Atlântico , Teorema de Bayes , Geografia , Filogenia , Especificidade da Espécie
13.
Nature ; 581(7806): 67-70, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32376955

RESUMO

In recent decades, intensive research on non-avian dinosaurs has strongly suggested that these animals were restricted to terrestrial environments1. Historical proposals that some groups, such as sauropods and hadrosaurs, lived in aquatic environments2,3 were abandoned decades ago4-6. It has recently been argued that at least some of the spinosaurids-an unusual group of large-bodied theropods of the Cretaceous era-were semi-aquatic7,8, but this idea has been challenged on anatomical, biomechanical and taphonomic grounds, and remains controversial9-11. Here we present unambiguous evidence for an aquatic propulsive structure in a dinosaur, the giant theropod Spinosaurus aegyptiacus7,12. This dinosaur has a tail with an unexpected and unique shape that consists of extremely tall neural spines and elongate chevrons, which forms a large, flexible fin-like organ capable of extensive lateral excursion. Using a robotic flapping apparatus to measure undulatory forces in physical models of different tail shapes, we show that the tail shape of Spinosaurus produces greater thrust and efficiency in water than the tail shapes of terrestrial dinosaurs and that these measures of performance are more comparable to those of extant aquatic vertebrates that use vertically expanded tails to generate forward propulsion while swimming. These results are consistent with the suite of adaptations for an aquatic lifestyle and piscivorous diet that have previously been documented for Spinosaurus7,13,14. Although developed to a lesser degree, aquatic adaptations are also found in other members of the spinosaurid clade15,16, which had a near-global distribution and a stratigraphic range of more than 50 million years14, pointing to a substantial invasion of aquatic environments by dinosaurs.


Assuntos
Dinossauros/anatomia & histologia , Dinossauros/fisiologia , Natação , Cauda/anatomia & histologia , Cauda/fisiologia , Água , Adaptação Fisiológica , Animais , Organismos Aquáticos/classificação , Organismos Aquáticos/fisiologia , Dieta/veterinária , Dinossauros/classificação , Ecossistema , Peixes , Robótica , Coluna Vertebral/anatomia & histologia
14.
Protist ; 171(2): 125713, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32325416

RESUMO

In many marine littoral and sublittoral benthic habitats, we find small diatoms with few features resolvable with light microscopy (LM) other than internal costae across their valves. While classically those internal costae have defined their identification and classification, the use of electron microscopy and of molecular data have started to reveal the true diversity of unrelated forms and genera (e.g., Anaulus, Eunotogramma, Hustedtiella, or Plagiogramma) which possess these structures. Here we describe the new genus Ambo, in an attempt to clarify some of the polyphyly of taxa with internal costa by formally transferring Anaulus balticus, Anaulus simonsenii, and Plagiogramma tenuissimum as well as Ambo gallaeciae, described here. Related to this, we attempt to document and characterize the genus Anaulus itself, which was formally described by Ehrenberg with an illustration. A search by LM of mica designated by Ehrenberg as the holotype of Anaulus scalaris, the generitype of Anaulus, failed to recover a specimen which adequately describes the genus to the exclusion of other genera with internal costa. We also present morphological and molecular data for Anaulus creticus and suggest a new genus-Ceratanaulus-to reflect the distinct morphological and molecular characters we documented.


Assuntos
Organismos Aquáticos/classificação , Organismos Aquáticos/genética , Biodiversidade , Diatomáceas/classificação , Diatomáceas/genética , Filogenia , Especificidade da Espécie
15.
An Acad Bras Cienc ; 92 Suppl 1: e20181245, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32348409

RESUMO

Several countries included the assessment of environmental drift contamination risk for the registration of pesticides. This practice is not yet totality effective in Brazil; however, due to the large number of pesticides in use, it is important to identify the real contamination risk during pesticide spraying. Therefore, this study determined the indices of environmental risks for exposure to drift from terrestrial applications of fungicides, herbicides, and insecticides that are used in soybean crops under Brazilian climate conditions and established buffer zones for the application of these products. Based on the three prediction drift models for soybeans in Brazil, risk indices were computed for aquatic organisms and terrestrial organisms according to the modelling procedures proposed by the POCER (Pesticide Occupation and Environmental Risk) and HAIR (Harmonized Environmental Indicators for Pesticide Risk) methodologies. In general, aquatic organisms are the most sensitive to drift contamination, being chlorothalonil, trifluralin and chlorpyrifos the ones that presented the higher risk indexes. No risk was found for earthworms; in contrast, the insecticides chlorpyrifos, spinosad and thiamethoxam presented risks to bees regardless of the nozzle (droplet size) used for the determination of the drift curve, resulting in the demand for different buffer zones.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Produtos Agrícolas , Monitoramento Ambiental/métodos , Praguicidas/toxicidade , Soja , Poluentes Químicos da Água/toxicidade , Animais , Organismos Aquáticos/classificação , Praguicidas/classificação , Medição de Risco
16.
Sci Data ; 7(1): 119, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32286314

RESUMO

Species distribution records are a prerequisite to follow climate-induced range shifts across space and time. However, synthesizing information from various sources such as peer-reviewed literature, herbaria, digital repositories and citizen science initiatives is not only costly and time consuming, but also challenging, as data may contain thematic and taxonomic errors and generally lack standardized formats. We address this gap for important marine ecosystem-structuring species of large brown algae and seagrasses. We gathered distribution records from various sources and provide a fine-tuned dataset with ~2.8 million dereplicated records, taxonomically standardized for 682 species, and considering important physiological and biogeographical traits. Specifically, a flagging system was implemented to signal potentially incorrect records reported on land, in regions with limiting light conditions for photosynthesis, and outside the known distribution of species, as inferred from the most recent published literature. We document the procedure and provide a dataset in tabular format based on Darwin Core Standard (DwC), alongside with a set of functions in R language for data management and visualization.


Assuntos
Organismos Aquáticos/classificação , Ecossistema , Feófitas/classificação , Clima
17.
Nat Commun ; 11(1): 692, 2020 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-32041961

RESUMO

Genetic diversity is estimated to be declining faster than species diversity under escalating threats, but its spatial distribution remains poorly documented at the global scale. Theory predicts that similar processes should foster congruent spatial patterns of genetic and species diversity, but empirical studies are scarce. Using a mined database of 50,588 georeferenced mitochondrial DNA barcode sequences (COI) for 3,815 marine and 1,611 freshwater fish species respectively, we examined the correlation between genetic diversity and species diversity and their global distributions in relation to climate and geography. Genetic diversity showed a clear spatial organisation, but a weak association with species diversity for both marine and freshwater species. We found a predominantly positive relationship between genetic diversity and sea surface temperature for marine species. Genetic diversity of freshwater species varied primarily across the regional basins and was negatively correlated with average river slope. The detection of genetic diversity patterns suggests that conservation measures should consider mismatching spatial signals across multiple facets of biodiversity.


Assuntos
Biodiversidade , Peixes/genética , Variação Genética , Animais , Organismos Aquáticos/classificação , Organismos Aquáticos/genética , DNA Mitocondrial/genética , Bases de Dados Genéticas , Meio Ambiente , Peixes/classificação , Geografia
18.
Sensors (Basel) ; 20(3)2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-32012976

RESUMO

An understanding of marine ecosystems and their biodiversity is relevant to sustainable use of the goods and services they offer. Since marine areas host complex ecosystems, it is important to develop spatially widespread monitoring networks capable of providing large amounts of multiparametric information, encompassing both biotic and abiotic variables, and describing the ecological dynamics of the observed species. In this context, imaging devices are valuable tools that complement other biological and oceanographic monitoring devices. Nevertheless, large amounts of images or movies cannot all be manually processed, and autonomous routines for recognizing the relevant content, classification, and tagging are urgently needed. In this work, we propose a pipeline for the analysis of visual data that integrates video/image annotation tools for defining, training, and validation of datasets with video/image enhancement and machine and deep learning approaches. Such a pipeline is required to achieve good performance in the recognition and classification tasks of mobile and sessile megafauna, in order to obtain integrated information on spatial distribution and temporal dynamics. A prototype implementation of the analysis pipeline is provided in the context of deep-sea videos taken by one of the fixed cameras at the LoVe Ocean Observatory network of Lofoten Islands (Norway) at 260 m depth, in the Barents Sea, which has shown good classification results on an independent test dataset with an accuracy value of 76.18% and an area under the curve (AUC) value of 87.59%.


Assuntos
Organismos Aquáticos/fisiologia , Biodiversidade , Ecossistema , Gravação em Vídeo/métodos , Animais , Organismos Aquáticos/classificação , Aprendizado Profundo , Humanos , Aumento da Imagem/métodos , Aprendizado de Máquina , Redes Neurais de Computação , Oceanos e Mares
19.
Science ; 367(6481): 1035-1038, 2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-32108111

RESUMO

Ecological differentiation is correlated with taxonomic diversity in many clades, and ecological divergence is often assumed to be a cause and/or consequence of high speciation rate. However, an analysis of 30,074 genera of living marine animals and 19,992 genera of fossil marine animals indicates that greater ecological differentiation in the modern oceans is actually associated with lower rates of origination over evolutionary time. Ecologically differentiated clades became taxonomically diverse over time because they were better buffered against extinction, particularly during mass extinctions, which primarily affected genus-rich, ecologically homogeneous clades. The relationship between ecological differentiation and taxonomic richness was weak early in the evolution of animals but has strengthened over geological time as successive extinction events reshaped the marine fauna.


Assuntos
Organismos Aquáticos/classificação , Biodiversidade , Extinção Biológica , Especiação Genética , Organismos Aquáticos/genética , Fósseis , Oceanos e Mares
20.
Syst Parasitol ; 97(1): 1-23, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31912420

RESUMO

We provide molecular data (cox1, 18S rDNA and 28S rDNA) for 17 acanthocephalan species and 20 host-parasite combinations from Australian marine teleosts collected from off Queensland, Australia. Fourteen of these acanthocephalans are characterised with molecular data for the first time and we provide the first molecular data for a species of each of the genera Heterosentis Van Cleave, 1931, Pyriproboscis Amin, Abdullah & Mhaisen, 2003 and Sclerocollum Schmidt & Paperna, 1978. Using 18S and 28S rDNA sequences, the phylogenetic position of each newly sequenced species is assessed with both single-gene and concatenated 18S+28S maximum likelihood and Bayesian inference analyses. Additional phylogenetic analyses focusing on the genus Rhadinorhynchus Lühe, 1912 and related lineages are included. Our phylogenetic results are broadly consistent with previous analyses, recovering previously identified inconsistencies but also providing new insights and necessitating taxonomic action. We do not find sufficient evidence to recognise the Gymnorhadinorhynchidae Braicovich, Lanfranchi, Farber, Marvaldi, Luque & Timi, 2014 as distinct from the Rhadinorhynchidae Lühe, 1912. The family Gymnorhadinorhynchidae and its sole genus, Gymnorhadinorhynchus Braicovich, Lanfranchi, Farber, Marvaldi, Luque & Timi, 2014, are here recognised as junior synonyms of Rhadinorhynchidae and Rhadinorhynchus, respectively. The two species currently assigned to Gymnorhadinorhynchus are recombined as Rhadinorhynchus decapteri (Braicovich, Lanfranchi, Farber, Marvaldi, Luque & Timi, 2014) n. comb. and Rhadinorhynchus mariserpentis (Steinauer, Garcia-Vedrenne, Weinstein & Kuris, 2019) n. comb. In all of our analyses, Rhadinorhynchus biformis Smales, 2014 is found basal to the Rhadinorhynchidae + Transvenidae Pichelin & Cribb, 2001, thus resulting in a paraphyletic Rhadinorhynchidae. It appears that R. biformis may require a new genus and family; however, morphological data for this species are currently insufficient to adequately distinguish it from related lineages, thus we defer the proposal of any new higher-rank names for this species. Species of the genus Sclerocollum, currently assigned to the Cavisomidae Meyer, 1932, are found nested within the family Transvenidae. We transfer the genus Sclerocollum to the Transvenidae and amend the diagnosis of the family accordingly. The genera Gorgorhynchoides Cable & Linderoth, 1963 and Serrasentis Van Cleave, 1923, currently assigned to the Rhadinorhynchidae, are supported as sister taxa and form a clade in the Polymorphida. We transfer these genera and Golvanorhynchus Noronha, Fabio & Pinto, 1978 to an emended concept of the Isthomosacanthidae Smales, 2012 and transfer this family to the Polymorphida. Lastly, Pyriproboscis heronensis (Pichelin, 1997) Amin, Abdullah & Mhaisen, 2003, currently assigned to the Pomphorhynchidae Yamaguti, 1939, falls under the Polymorphida in our analyses with some support for a sister relationship with the Centrorhynchidae Van Cleave, 1916. As this species clearly does not belong in the Pomphorhynchidae and is morphologically and molecularly distinct from the lineages of the Polymorphida, we propose the Pyriprobosicidae n. fam. to accommodate it.


Assuntos
Acantocéfalos/classificação , Acantocéfalos/genética , Organismos Aquáticos/parasitologia , Peixes/parasitologia , Filogenia , Animais , Organismos Aquáticos/classificação , Organismos Aquáticos/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Queensland , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , Especificidade da Espécie
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...