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Padrões de infecções parasitárias em peixes de uma planície de inundação: uso de traços funcionais e filogenia de peixes e parasitas.
No full textFunctional traits are the measurable properties of organisms that influence their performance through their effects on individual growth, survival, and reproduction. Therefore, the choice of functional characteristics is essential for drawing solid ecological conclusions and predicting ecosystem properties and interactions between organisms. The structure of the parasite community can vary over time and space, resulting from variations in host characteristics, phylogenetic relationships, and environmental characteristics. These can be examined at different levels of diversity: alpha (local diversity) and beta (variation in community composition between locations), including multiple facets such as taxonomic (TD), functional (FD), and phylogenetic (PD). We evaluated which host characteristics may be determinant in the composition of fish parasites from the upper Paraná River floodplain; and compared different facets of endoparasite biodiversity at the sampling unit level (α diversity or parasite diversity at the level of an individual host) and between sampling units (parasite diversity within (β1) or between (β2) host individuals of a species). The host's diet was the factor that had the greatest influence on the composition and similarity of endoparasites in floodplain fish. The α diversity of endoparasite species differed mainly in terms of TD and PPD. Regarding β diversity, the parasite communities presented patterns grouped at different levels (β1 and β2, respectively). To explain patterns in endoparasite diversity, functional traits, and fish phylogeny act as drivers of parasite community structure, with diet being one of the main factors. And the assembly patterns in the endoparasite infracommunities of different floodplain host species reflect the characteristics of their component and composite communities.As características funcionais são as propriedades mensuráveis dos organismos que influenciam seu desempenho por meio de seus efeitos no crescimento, sobrevivência e reprodução individual. Dessa forma, a escolha das características funcionais são essencias para tirar conclusões ecológicas sólidas, bem como prever propriedades do ecossistema e interações entre organismos. A estrutura da comunidade parasitária pode variar ao longo do tempo e do espaço, resultante de variação das características dos hospedeiros, relações filogenéticas e características do ambiente. Estas podem ser examinadas em diferentes níveis de diversidade: alfa (diversidade local) e beta (variação da composição da comunidade entre locais), incluindo múltiplas facetas, como a taxonômica (TD), funcional (FD) e filogenética (PD). Avaliou-se quais características do hospedeiro podem ser determinantes na composição dos parasitas de peixes da planície de inundação do alto rio Paraná; e comparou-se as diferentes facetas da biodiversidade de endoparasitas no nível da unidade amostral (diversidade α ou diversidade parasitária no nível de um hospedeiro individual) e entre unidades amostrais (diversidade de parasitas dentro de (β1) ou entre (β2) indivíduos hospedeiros de uma espécie). A dieta do hospedeiro foi o fator que apresentou maior influência na composição e similaridade dos endoparasitas em peixes da planície de inundação. A diversidade α das espécies de endoparasitas diferiu principalmente em termos de TD e PPD. Quanto à diversidade β, as comunidades parasitárias apresentaram padrões agrupados em diferentes níveis (β1 e β2, respectivamente). Para explicar padrões na diversidade de endoparasitas, as características funcionais e a filogenia de peixes atuam juntas como impulsionadores da estrutura da comunidade parasitária, sendo a dieta um dos principais fatores. E os padrões de montagem nas infracomunidades de endoparasitas de diferentes espécies hospedeiras da planície de inundação refletem as características de suas comunidades componentes e compostas.Ph
Compositional analysis of invertebrate communities in Raja Ampat conservation zones using environmental DNA (eDNA)
No full textRaja Ampat conservation area is divided into three zones: the core zone, the tourism zone, and the open zone. This region is crucial for sustainable fisheries and environmental management, yet it is under significant anthropogenic pressure. Accurate species detection is essential for inventory and diversity surveys, and environmental DNA (eDNA) methods have been shown to be more effective than conventional techniques. This study aimed to evaluate whether V9 primers could detect multispecies invertebrate compositions, assess community structure and contributions within each zone, and identify significant differences in invertebrate diversity among the zones. A total of 66 eDNA samples were collected from water and sediment columns across the three zones. Samples were extracted using the NucleoSpin™ kit (Macherey-Nagel) protocol, amplified with universal eukaryote primers targeting the 18S gene, and sequenced using Illumina MiSeq. Taxonomic analysis was performed using QIIME2 software and the SILVA database. The study identified 19 invertebrate species. The Shannon-Wiener (H') and Simpson (D) indices revealed greater species diversity in the core zone compared to the tourism and open zones. However, the Kruskal-Wallis test indicated no significant differences in species diversity across the zones. SIMPER analysis demonstrated a high percent contribution of species in each zone. This study highlights the effectiveness of eDNA methods for biodiversity assessment and offers valuable insights into invertebrate community structures within the Raja Ampat conservation area.PublishedReferee
Ocean Decade Vision 2030 White Papers - Challenge 10: Restoring Society's Relationship with the Ocean.
No full textBy 2030, success for Ocean Decade Challenge No. 10 will be evidenced through a culture shift in the ocean community leading to implicit understanding that ocean threats are an outcome of human behaviour. This will require a shift in the way that ocean science, in the broad sense as defined in the Decade, is formulated, practiced, and communicated to ensure that all sectors of society have strengthened emotional connections with the ocean, and understand the vital role that the ocean plays in human and planetary well-being, including climate stability. All members of society across regions, sectors, and scales will have increased motivation, capability, and opportunity to make decisions and behave in ways that ensure a healthy ocean. By 2030, success for Ocean Decade Challenge No. 10 will include fulfilment of critical science and knowledge gaps: Increased priority and practice of science that embraces multiple knowledge systems and transdisciplinary collaboration Increased priority of Indigenous-led research, consistent with the supporting articles of the United Nations Declaration on the Rights of Indigenous Peoples (UNDRIP), inherent rights, and signed treaty obligations with Indigenous Nations Increased priority of marine social sciences, particularly: public perceptions ocean research marine citizenship and identity research behavioural science research linked to ocean-climate education and communications research on how ocean literacy can be measured and monitored over time, and the impacts of an ocean literate society on ocean health research on ocean literacy as a policy tool science communication through multiple approaches including immersive technology, storytelling, and the arts Success will also depend on the generation, sharing, and use of the following priority datasets: human-ocean connection/human-ocean values dataset(s) pro-ocean behaviour change methodologies, case studies, and effective practices impact mapping of regional and key global ocean literacy initiatives ocean culture mapping that includes a global body of evidence (contextual, local knowledge) that demonstrates and supports cultural engagement as an enabler of ocean-human health. It will include the development of: a co-designed theory of change to action key drivers of Challenge 10, in which regional expertise helps guide the initial and ongoing strategic direction of the newly launched Decade Coordinating Office (DCO), Connecting People and Ocean a guiding portfolio of best practices on research co-design, co-production, co-implementation, and co-evaluation, respectfully bridging different forms of knowledge, ensuring mutual recognition and benefits, and nurturing long-term relationships with each other and nature a collaborative global, multi-dimensional ocean literacy survey tool (i.e., Ocean & Society Survey) to measure ocean connection and values, as well as motivators, enablers, barriers to action and behaviour change a global network of ocean communications experts and regional ocean communications communities of practice to support training, accreditation, upskilling, knowledge exchange, and impact measurement a global network of ocean-climate education experts (formal, informal, and non-formal) to support teacher training, certification programmes, and knowledge exchange a Global Blue Schools Network, building off the All-Atlantic and European Blue Schools Networks, to bridge practitioner best practices with research and training a global framework for sharing successful community projects that demonstrate practices and solutions specific to cultural connections, heritage, language, and place-based innovations for ocean-human health.PublishedReferee
Influence of priority effect on the establishment of two aquatic macrophyte species.
No full textSpecies that arrive first at a site can impact the success of those that arrive later due to competition and changes in the environment, a process known as the “priority effect”. This study evaluates how the priority effect influences competition between two species native to South America, one highly invasive outside its area of origin (Alternanthera philoxeroides) and another with high invasive potential in other regions (Polygonum ferrugineum). This research tests the hypothesis that the negative effect on the growth and competitive ability of one of the species is greater when the other species is already established (priority effect). An experiment was carried out with five treatments: two treatments with each of the species planted a priori, one treatment with both planted simultaneously and two monocultures. From the biomass values obtained, the relative intensity of competition (ICR) and the relative growth rate (RGR) were calculated. For both species, the ICR values calculated for aboveground biomass, root biomass, total biomass and root biomass: above biomass ratio were higher in the presence of the priority effect. Congruent with these results, the RGR of the species was lower in the presence of the priority effect. This study shows that stochastic effects, such as the order of arrival of one of the species, can be decisive for the success of the other species under natural conditions.Espécies que chegam primeiro em um local podem impactar o sucesso das que chegam depois devido à competição e mudanças no ambiente, processo conhecido como “efeito de prioridade”. Este estudo avalia como o efeito prioritário influencia a competição entre duas espécies nativas da América do Sul, uma altamente invasora fora da sua área de origem (Alternanthera philoxeroides) e com alto potencial invasor em outras regiões (Polygonum ferrugineum). A pesquisa testa a hipótese de que a que o efeito negativo sobre o crescimento e a habilidade competitiva de uma das espécies é maior quando a outra espécie se encontra estabelecida (efeito de prioridade). Foi realizado um experimento com cinco tratamentos: dois tratamentos com cada uma das espécies plantadas à priori, um tratamento com ambas plantadas simultaneamente e duas monoculturas. A partir de valores de biomassa obtidos, foi calculada a intensidade relativa da competição (RCI) e a taxa de crescimento relativo (TCR). Para ambas as espécies, os valores do RCI calculados para a biomassa aérea, biomassa de raízes, biomassa total e proporção biomassa de raízes: biomassa aérea foram maiores na presença do efeito prioritário. De forma congruente com esses resultados, a TCR das espécies foi menor na presença do efeito prioritário. Esse estudo mostra que efeitos estocásticos, como a ordem de chegada de uma das espécies, podem ser determinantes para o sucesso da outra espécie em condições naturais.Master
Assessment of three small tuna stocks exploited by the algerian fleet using the CMSY Method.
No full textEstimating the stock status is one of the most fundamental parts of fisheries management intended to preserve the aquatic resources. In this, study the assessment of three stocks of small tunas (Atlantic bonito Sarda sarda, Little tunny Euthynnus alletteratus and Bullet tuna Auxis rochei) caught in the algerian basin (Geographical Sub-Areas 4) was assessed using CMSY method. This method is suitable for data limited stocks and used to estimate maximum sustainable yield (MSY) and related fisheries reference points (Bmsy, Fmsy) from catch and resilience. The results of CMSY model suggest that the stocks of the Atlantic bonito and the Little tunny are overfished (0.5≤B2020/Bmsy<0.8) but not subject to overfishing (F2020/Fmsy≤1). The stock of Bullet tuna was assessed as overfished (B2020/Bmsy=0.639) and subject to overfishing (F2020/Fmsy=1.56). Results obtained from this first study provide a diagnosic of the stock status of these species, that needs to be refined by applying other models.Références bibliographiques, Tableaux, Figures.PublishedReferee
Warm conveyor belt activity over the Pacific: modulation by the Madden–Julian Oscillation and impact on tropical–extratropical teleconnections
No full textResearch in the last few decades has revealed that rapidly ascending airstreams in extratropical cyclones – socalled warm conveyor belts (WCBs) – play an important role in extratropical atmospheric dynamics. However on the subseasonal timescale, the modulation of their occurrence frequency, henceforth referred to as WCB activity, has so far received little attention. Also, it is not yet clear whether WCB activity may affect tropospheric teleconnection patterns, which constitute a source of predictability on this subseasonal timescale. Using reanalysis data, this study analyzes the modulation of WCB activity by the Madden–Julian Oscillation (MJO). A key finding is that WCB activity increases significantly over the western North Pacific when the convection of the MJO is located over the Indian Ocean. This increased WCB activity, which is stronger during La Niña conditions, is related to enhanced poleward moisture fluxes driven by the circulation of subtropical Rossby gyres associated with the MJO. In contrast, when the convection of the MJO is located over the western North Pacific, WCB activity increases significantly over the eastern North Pacific. This increase stems from a southward shift and eastward extension of the North Pacific jet stream. However, while these mean increases are significant, individual MJO events exhibit substantial variability, with some events even exhibiting anomalously low WCB activity. Individual events of the same MJO phase with anomalously low WCB activity over the North Pacific tend to be followed by the known canonical teleconnection patterns in the Atlantic–European region; i.e., the occurrence frequency of the positive phase of the North Atlantic Oscillation (NAO) is enhanced when convection of the MJO is located over the Indian Ocean and similarly for the negative phase of the NAO when MJO convection is over the western North Pacific. However, the canonical teleconnection patterns are modified when individual events of the same MJO phase are accompanied by anomalously high WCB activity over the North Pacific. In particular, the link between MJO and the negative phase of the NAO weakens considerably. Reanalysis data and experiments with an idealized general circulation model reveal that this is related to anomalous ridge building over western North America favored by enhanced WCB activity. Overall, our study highlights the potential role of WCBs in shaping tropical–extratropical teleconnection patterns and underlines the importance of representing them adequately in numerical weather prediction models in order to fully exploit the sources of predictability emerging from the tropics.PublishedReferee
Ecological characteristic of hermit crabs in Lhokseumawe mangrove forest, Aceh, Indonesia
No full textThe study was conducted between August and September of 2021 in order to determine the density, ecological index, distribution pattern, geographic distribution, environmental factors, and the relationship between hermit crabs and environmental factors. Hermit crabs were gathered using a quadratic transect and sample plots, while environmental variables were measured in situ. PCA and CCA multivariate statistics were used to determine the characteristics and correlation between hermit crabs and environmental factors. Hermit crabs were discovered to be comprised of two species (Clibanariuslongitarsus and C. infraspinatus) and one family (Diogenidae), with the highest density found in the C. longitarsus species (1.22 ± 0.57 – 4.68 3.53 ind/m2), diversity index is categorized as moderate (2.01), the geographical distribution is abundant (>80%), and environmental factors are categorized as good. In addition, Stations I and II have high DO, TOM, mangrove density, C. longitarsus, and C. infraspinatus parameters, whereas Station III has high salinity, pH, and temperature, with salinity, mangrove density, and TOM being the most influential parameters on hermit crab density.PublishedReferee
Ocean Decade Vision 2030 White Papers – Challenge 4: Develop a Sustainable and Equitable Ocean Economy.
No full textThis draft White Paper is one of a series of ten White Papers all of which have been authored by an expert Working Group. Accompanied by a synthesis report authored by the Decade Coordination Unit, it will be discussed at the 2024 Ocean Decade Conference before being finalised and published. 1.2 Strategic Ambition of Ocean Decade Challenge No. 4 By 2030, success for Ocean Decade Challenge No. 4: Develop a sustainable and equitable ocean economy, will be marked by significant advancements in establishing a knowledge-driven framework for informed decision-making and policy formulation. There will be enhanced collaboration among stakeholders, ensuring diverse community engagement and equitable benefit sharing while acknowledging and prioritising the culture, identity, and rights of IPLC that have historically depended on and thrived alongside ocean resources. Strategic mobilisation of blue finance will support investments in sustainable coastal and marine infrastructure, innovative technologies, and conservation efforts, reinforcing the economic foundation. Key policies and governance frameworks promoting sustainability and equity will be in place, alongside a balanced and reflective approach, laying the groundwork for a resilient and inclusive ocean economy. This success will be underpinned by improved data accessibility and capacity-sharing efforts, fostering a shared understanding and commitment to sustainable ocean use. Success will include fulfilment of the following critical science and knowledge gaps: addressing the interface between knowledge systems, policy implementation, and public-private partnerships to enable informed decision-making, focusing on biodiversity restoration, protection, and sustainable management as foundational elements of a sustainable and equitable ocean economy, and ensuring the inclusion of local and indigenous knowledge alongside environmental sustainability and social equity. The following priority datasets gaps will be targeted: comprehensive and up-to-date data on both human activities and state of the environment supporting informed and equitable decision-making and ensuring stakeholder and rights holder engagement in data capture and knowledge co-production. It will include robust capacity development and sharing as well as knowledge exchange to deepen understanding of ocean-human activity interconnections, emphasising investment in context-specific education, training, and research programs, and the integration of appropriate technology and innovation to support a sustainable, equitable, and resilient ocean economy and ensuring that future generations can benefit from the ocean's diverse resources and opportunities.PublishedReferee
Turnover and nestedness of aquatic hyphomycetes in subtropical streams from different land uses.
No full textStreams, small rivers, are endowed with exclusive energetic dynamics: decomposition of allochthonous material, and formation of microhabitats and ecotones between aquatic communities and riparian vegetation. Regarding this input of organic matter, aquatic fungi make up most of the biomass of organic matter decomposers, they are biomineralizers of foliar nutrients and through decomposition link the matter to the entire trophic network. Aquatic fungi are a polyphyletic group adapted to this environment, and have different taxonomic levels grouped together. These microorganisms are the target of ecological studies due to their important, still their spatial distribution still lacks elucidation, as well as the influence of limnological on biotic parameters. The fungal communities, composition and beta diversity, were investigated in this study separated into two approaches: i) the beta diversity of aquatic fungi in streams under different land uses; ii) the nesting of fungal eDNA sequences in a protected area and an impacted area. The biotic data were obtained from leaf mixes, and represent the biodiversity of the aquatic FUNGA present in streams of the Atlantic Forest, being pioneering studies for the subtropical region. Furthermore, the results may contribute as a basis for future studies within the mycology of aquatic environments. Approach I, in a taxonomic approach, demonstrated fungal diversity in presence of ambiental heterogeneity. Approach II, through metabarcoding, demonstrates the sensitivity of the use of genomic databases in ecological analyses. The results presented here reinforce the need for management and conservation plans for riparian vegetation, which forms the aquatic microecosystem, used by fungi for their decomposition and other ecosystem functions.Os riachos, rios de pequena ordem, são dotados de dinâmicas energéticas exclusivas: formação de microhabitats, formação de ecótonos entre comunidades aquáticas e vegetação ripária, e a decomposição deste material alóctone. A respeito deste input de matéria orgânica, os fungos aquáticos compõem a maior parte da biomassa de decompositores de matéria orgânica e atuam como biomineralizadores dos nutrientes foliares ao disponibilizarem à toda rede trófica. Os fungos aquáticos são um grupo polifilético de fungos adaptados a este ambiente, e apresentam diferentes níveis taxonômicos agrupados. Estes microrganismos são alvo de estudos ecológicos devido a sua importância, sua distribuição espacial ainda carece de esclarecimentos, bem como a influência dos parâmetros limnológicos sobre os bióticos. As comunidades fúngicas, composição e beta diversidade, foram investigadas neste estudo separado em duas abordagens: i) a beta diversidade de fungos aquáticos em riachos sob diferentes usos da terra; ii) o aninhamento de sequências de eDNA fúngico em uma área protegida e outra antropizada. Os dados bióticos foram obtidos de mixes de folhas, e representam a biodiversidade da funga aquática dos riachos da Mata Atlântica, sendo estudos pioneiros para a região subtropical. Ademais, as abordagens dispõem de resultados que podem contribuir como base para futuros estudos dentro da micologia de ambientes aquáticos. A primeira abordagem, taxonômica, demonstrou a diversidade fúngica na presença de heterogeneidade ambiental. A segunda abordagem, através do metabarcoding, demonstra a sensibilidade do uso de banco de dados genômicos em análises ecológicas. Os resultados aqui obtidos indicam a necessidade de planos de manejo e conservação da vegetação ripária, que forma o microecossistema aquático, utilizado por fungos para sua decomposição e demais funções ecossistêmicas.Master
Frequency histograms, condition parameters and size-depending metal accumulation in two species belonging to Phorcus genus.
No full textThis work is a biological and ecotoxicological investigation in two Trochidae species Phorcus turbinatus and Phorcus articulatus taken from four stations, monthly for biological study and seasonally for size-depending metal monitoring. Our results related to biological characterization suggested mostly polymodal frequency histograms associated with a continual renewal of juveniles indicating a laying period spread over several months. The condition index revealed similar values slightly decreasing during hot seasons probably due to the coincidence of the spawning period with the spring and the summer. As for the condition factor, it also presented close values with a slight increase during the periods of March-April, June-July and even September-November probably resulting from algal proliferation and trophic availability during those months. The estimation of metal pollution indicators proposed an increasing classification of contamination related to the amounts of waste ejections at each locality coming from industrial activity, large fishing ports and mooring areas. Size-depending metal analyses revealed that despite the strong contamination, a moderate concentration decrease was associated with size growth. This life strategy would allow these species to counteract unfavorable conditions and ensure their persistence and thus justify their frequent use as bio-indicators of the state of health in coastal ecosystems.PublishedReferee