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Analysis of wave climate and energy potential of intermediate waters in the marine sphere of influence of the main ports of the Colombian Caribbean
No full textEste trabajo presenta un estudio del clima de oleaje para el mar Caribe colombiano, entre las coordenadas 8° N y 16° N de latitud y 84° W y 70° W de longitud, y su potencial energético en los puntos de aguas intermedias en el área de influencia marítima en los principales puertos del Caribe colombiano, que sirven de insumo a los intereses marítimos del país. Se realizó con base en análisis de simulaciones de propagación de oleaje de un período de 30 años elaborado en el Centro de Investigaciones Oceanográficas e Hidrográficas del Caribe, utilizando el modelo Simulating Wave Nearshore, forzado con los vientos del Reanálisis Regional de América del Norte de 1979 a 2010, y validado con información de boyas direccionales de la Dirección General Marítima y de la Administración Nacional Oceanográfica y Atmosférica en el mar Caribe. Los resultados muestran cuatro regiones del Caribe colombiano con características similares de altura, período y dirección de ola. La primera es la región insular de San Andrés y Providencia; la segunda, una región sur entre Urabá y Cartagena; una tercera es la región central, entre Barranquilla y Santa Marta; la cuarta corresponde a la parte norte, entre Riohacha y Puerto Bolívar. Los valores más altos de altura de ola se observan en Barranquilla y Santa Marta y los más bajos en Urabá. Adicionalmente, se evaluó la capacidad de energía renovable obtenida por medio del oleaje a partir del espectro de energía potencial para boyas virtuales en los principales puertos. Se encontró que la energía se concentra entre 4 s a 6 s de periodo, y entre 0.5 m y 3 m en alturas de ola, para las boyas de Barranquilla, Santa Marta, Puerto Bolívar y Providencia; siendo Barranquilla el sitio de mayor potencial que se encuentra entre 7 s y 4 m, seguida de Santa Marta entre 6 s y 3.8 m. El potencial energético promedio anual presenta valores altos entre diciembre y marzo; medios, entre junio y agosto; valores bajos, en mayo, y entre septiembre y noviembre, correspondientes a las épocas seca y húmeda. Las condiciones del oleaje encontradas superan el umbral necesario para generar energía con un sistema de energía alternativa tipo Wave Energy Converter, con potenciales de rendimiento aceptables que podrían multiplicarse mediante la instalación de parques energéticos.This paper presents a study of the wave climate of the Colombian Caribbean Sea, between coordinates 8° N and 16° N latitude and 84° W and 70° W longitude, and the energy potential at intermediate water points within the area of the Colombian Caribbean, which serve as inputs for the country's maritime interests. It was carried out based on the analysis of wave propagation simulations for 30 years developed at the Center for Oceanographic and Hydrographic Research of the Caribbean (CIOH), using the SWAN (Simulating WAves Nearshore) model, forced with the winds of the North American Regional Reanalysis (NARR) from 1979 to 2010 and validated with directional buoy data from the Colombian General Maritime Directorate (Dimar) and the United States National Oceanographic and Atmospheric Administration (NOAA) in the Caribbean. The results show four regions of similar wave height, period, and directional characteristics in the Colombian Caribbean. The first is the region around the islands of San Andrés and Providencia, and the second is a southern region between Urabá and Cartagena. A third comprises the central region around Barranquilla and Santa Marta, and the fourth, between Riohacha and Puerto Bolivar, occupies the northern part. The highest wave height values are observed for Barranquilla and Santa Marta, while the lowest are at Urabá. Furthermore, we evaluated the renewable wave energy capacity by studying the potential energy spectrum for virtual buoys in the primary ports. We observed that the energy was concentrated between 4 s and 6 s, with wave heights ranging from 0.5 m to 3 m for buoys in Barranquilla, Santa Marta, Puerto Bolivar, and Providencia. Amongst these, Barranquilla displayed the highest potential, with a period of 7 s and a wave height of 4m, followed by Santa Marta with values of 6 s and 3.8 m. The annual pattern of average energy potential revealed high values between December and March, medium values from June to August, and low values in May and between September and November; demonstrating that there is greater energy in the dry seasons and lower energy in the wet seasons. The wave conditions detected surpass the necessary threshold for energy generation via a Wave Energy Converter (WEC) alternative energy system, offering highly promising yield potentials, which could be magnified through the use of energy parksPublishedNot Know
Situação atual e projecções futuras da pesca de peixes multiespecíficos na região sudeste de Cuba.
No full textLas pesquerías multiespecíficas de peces en Cuba incluyen alrededor de 150 especies, diferentes artes de pesca que se utilizan simultáneamente y un número elevado de puertos de desembarques, lo que dificulta el monitoreo y la evaluación de estos recursos, por lo cual el manejo ha sido limitado. Por ello nos propusimos evaluar el estado actual, así como las compensaciones futuras en biomasa, captura y ganancias de las especies más vulnerables bajo diferentes estrategias de manejo. Mediante el método Catch-MSY se estimó el estado actual, y un modelo bioeconómico se empleó para realizar las proyecciones a largo plazo de las salidas. Los stocks estudiados se encuentran agotados, y la mayoría con valores que implican un alto riesgo para la sustentabilidad de sus poblaciones. Además, la mayoría están sobreexplotados y sufren pesca ilegal. Sin embargo, a largo plazo bajo estrategias de manejo sustentable, muestran oportunidades de recuperación y de tener pesquerías económicamente rentables siempre que se elimine la pesca ilegal y se apliquen incentivos económicos.Multispecies fish fisheries in Cuba include about 150 species, different fishing gears used simultaneously and a large number of landing ports, which makes monitoring and assessment of these resources difficult, and management has been limited. We therefore set out to evaluate the current status, as well as future trade-offs in biomass, catch and earnings of the most vulnerable species under different management strategies. The Catch-MSY method was used to estimate the current status, and a bioeconomic model was used to make long-term projections of the outputs. The stocks studied are depleted, and most of them have values that imply a high risk for the sustainability of their populations. In addition, most are overexploited and suffering illegal fishing. However, in the long term, under sustainable management strategies, they show opportunities for recovery and economically profitable fisheries, provided that illegal fishing is eliminated and economic incentives are applied.PublishedReferee
Influence of attractant feeds on the endoparasitic fauna of Brycon falcatus (Characidae: Bryconinae) from the rio Teles Pires, southern Amazonia.
No full textStudies on endoparasitic fauna provide valuable biological information, such as migration habits, population breakdown and host feeding habits. Several species of endoparasites are transmitted via trophic web and have complex life cycles with two or more hosts, which characterizes the trophic interactions between organisms. In this sense, the objective of this work was to evaluate the impact of attractant feeds (soybeans, corn) on the diet and on the endoparasitic fauna of Brycon falcatus, collected in the Amazon basin. The specimens were collected using a line hook, fishing rod and gill nets. Then the fish were euthanized and the stomach and intestines of each specimen were analyzed fresh. Two species of nematodes were identified, Procamallanus (Spirocamallanus) inopinatus and Philonema sp.. The diet of B. falcatus was composed of aquatic and terrestrial insects and attractant feeds, which are composed of soybeans and corn, being considered as an item of anthropic origin, which characterized it as an omnivore with a tendency to herbivory. The aquatic insects found in the diet of B. falcatus may possibly act as intermediate hosts for P. (S.) inopinatus and Philonema sp.. Among the endoparasites, it was observed that P. (S.) inopinatus presented greater abundance, intensity and prevalence parasitic compared to Philonema sp.. It was found that non-parasitized individuals had a higher condition factor than parasitized individuals. There was a significant difference in the condition factor between individuals who had the presence or absence of attractant feeds in the digestive tract. Consequently, B. falcatus was influenced by anthropic items on Kn, as specimens that did not consume this food item had a higher Kn compared to fish that ate attractant feeds. Based on the results obtained, it is possible to verify that the diet of B. falcatus had a greater representation of natural food items, such as stems and barks, Coleoptera and Ephemeroptera. However, there was an impact of attractant feeds ingestion on the relative condition factor of the specimens, requiring greater inspection to avoid this anthropic action that can negatively affect the environmental and the local fauna.Estudos sobre a fauna endoparasitária fornecem informações biológicas valiosas, como hábitos de migração, desagregação de população e os principais itens alimentares do hospedeiro. Várias espécies de endoparasitos são transmitidas via teia trófica e apresentam ciclos de vida complexos tendo dois ou mais hospedeiros, o que caracteriza as interações tróficas entre organismos. Avaliou-se o impacto da “ceva” na dieta e na fauna endoparasitária de Brycon falcatus, coletados na bacia amazônica. Os espécimes foram coletados utilizando anzol de linha, vara de pesca e redes de emalhar. Em seguida, os peixes foram eutanaziados e o estômago e intestino de cada espécime foi triado à fresco. Foram identificadas duas espécies de nematóides, Procamallanus (Spirocamallanus) inopinatus e Philonema sp.. A dieta de B. falcatus foi composta por insetos aquáticos, terrestres e “ceva”, a qual é composta por soja e milho, sendo considerada um item de origem antrópica, o que o caracterizou como onívoro com tendência à herbivoria. Os insetos aquáticos encontrados na dieta de B. falcatus foram considerados possíveis hospedeiros intermediários de P. (S.) inopinatus e Philonema sp.. Dentre os endoparasitos, observou-se que P. (S.) inopinatus apresentou maior abundância, intensidade e prevalência parasitária em comparação com Philonema sp.. Constatou-se que os indivíduos não parasitados apresentaram maior fator de condição do que os indivíduos parasitados. Houve diferença significativa no fator de condição entre indivíduos que apresentavam a presença ou ausência de “ceva” no trato digestório. Consequentemente, B. falcatus sofreu influência de itens antrópicos no Kn, pois exemplares que não consumiram este item alimentar apresentaram um Kn maior em comparação com os peixes que ingeriram “ceva”. Mediante os resultados obtidos verificou-se que a dieta de B. falcatus teve maior representatividade de itens alimentares naturais, como talos e cascas, Coleoptera e Ephemeroptera. Entretanto, houve o impacto da ingestão de “ceva” no fator de condição relativo dos espécimes, necessitando de maior fiscalização para evitar esta ação antrópica que pode afetar negativamente o ambiente e a fauna local.Master
Introduction to the Workshop "Conservation and sustainable use of marine biological diversity of areas beyond national jurisdiction (BBNJ)"
No full textIn the first part of the introductory video (1/6), Prof. Dr. Andree Kirchner (@ISRIM) and Prof. Dr. Lorenzo Schiano di Pepe (@Uni.Genova) are giving some background information about the workshop "Conservation and sustainable use of marine biological diversity of areas beyond national jurisdiction (BBNJ)". In the second part of the introductory video, Prof. Dr. Marco Giovine (Centro del Mare, @Uni.Genova) explains the importance of the topic from the perspective of the Centre of the Sea at the University of Genoa. The presentations are part of the workshop "Conservation and sustainable use of marine biological diversity of areas beyond national jurisdiction (BBNJ)", which took place in the framework of the 9th Summer School on the European Union and the Law of the Sea (EULoS). It was organized by the Institute for the Law of the Sea and International Marine Environmental Law (ISRIM) and the University of Genoa on 1 September 2023. The workshop is an UN Ocean Decade Activity.Challenge 2: Protect and restore ecosystems and biodiversity; Challenge 10: Change humanity's relationship with the oceanPublishedReferee
Воздействие фунгицида «Каюнис, КЭ» на различные звенья трофической цепи в модельном эксперименте
No full textCurrently, there is an ongoing process of development of the next-generation pesticides, which use for the purposes of agriculture has negative implications for the environment. Their hazard potential is attributable to two factors: high biological activity and their application method involving their dispersion in the environment. It necessitates the investigation of the effect of pesticides on aquatic organisms, which includes changes in their habitat, disruptions of their vital functions, especially at the early stages of their ontogeny, accumulation in their tissues, and movement along the trophic chain. Toxicological assessment of the fungicide Cayunis, EC effect has been conducted on the aquatic organisms of various taxonomic groups: microalgae (Scenedesmus guadricauda (Turpin) Brébisson, 1835), macrophytes (Elodea canadensis Michaux, 1803), molluscs (Planorbarius corneus (Linnaeus, 1758)), embryos and fry of the round goby (Neogobius melanostomus (Pallas, 1814)). Over the course of the experiment, the conditions for intoxication were identified, and the toxicometric characteristics of the aquatic organisms belonging to various trophic levels were estimated. Using an experimental approach, the threshold and no observed effect concentrations of the preparative form of Cayunis, EC pesticide have been identified for each test subject. This study made it possible to compare the sensitivity of each investigated test subject to the fungicide. Among the studied test subjects, round goby fry has proved to be the most sensitive to the effect of Cayunis, EC fungicide.В настоящее время создаются пестициды новых поколений. Применение их в сельском хозяйстве неизбежно связано с негативными экологическими последствиями. Опасность пестицидов обусловлена двумя обстоятельствами: высокой биологической активностью и технологией применения, приводящей к их рассеиванию в окружающей среде. Важным аспектом является изучение их воздействия на гидробионтов. Применение пестицидов приводит к изменению привычной среды обитания и нарушению жизнедеятельности водных организмов, особенно на ранних стадиях онтогенеза, их накоплению в гидробионтах и передаче по трофической цепи. Токсикологическая оценка воздействия фунгицида «Каюнис, КЭ» проводилась на гидробионтах разных систематических групп: микроводоросли (Scenedesmus guadricauda (Turpin) Brébisson, 1835), макрофиты (Elodea canadensis Michaux, 1803), моллюски (Planorbarius corneus (Linnaeus, 1758)), эмбрионы и мальки бычка-кругляка (Neogobius melanostomus (Pallas, 1814)). В ходе эксперимента подбирались условия интоксикации и рассчитывались токсикометрические показатели для гидробионтов различных трофических уровней. Для каждого тест-объекта экспериментальным путем устанавливались пороговые и недействующие концентрации препаративной формы «Каюнис, КЭ». Исследования позволили сравнить чувствительность к фунгициду изученных тест-объектов. Из изученных нами тест-объектов мальки бычка-кругляка оказались наиболее чувствительными к воздействию фунгицида «Каюнис, КЭ».PublishedReferee
Unveiling the quarries world: outreach and dissemination session in the framework of Fishtuna Festival 2023
No full textDuring the last edition of Fishtuna festival I had the opportunity to share some insights from field-based research conducted in the Aegadian Islands MPA in 2016-2017. This event shed light on local traditions and on the intangible heritage of the Aegadian Archipelago, focusing on traditions from multiple perspectives: art, tourism and traditional food. On this perspective, I briefly introduced through a video projection, an extract of the work performed in collaboration with the Aegadian Islands MPA and the University of Rome in 2016-2017 dedicated to another relevant aspect of the cultural heritage of this place: the quarries of the eastern portion of Favignana island.TEMPOREALEPublishedNot Know
Workshop on the Development of Quantitative Assessment Methodologies based on Life- history traits, exploitation characteristics, and other relevant parameters for data-limited stocks (WKLIFEXII)
No full textThe objective of the Twelfth Workshop on the Development of Quantitative Assessment Methodologies based on Life-history traits, exploitation characteristics, and other relevant parameters for data-limited stocks (WKLIFE XII) was to further develop methods for stock assessment, stock status, and catch advice for stocks in ICES Categories 2–6, focusing on the provision of sound advice rules adhering to the ICES advisory framework and principles for fisheries management. This report addresses (i) questions from different ICES assessment working groups and stakeholders regarding the applicability of the data-limited technical guidelines, (ii) the prioritisation of future tasks regarding the ICES data-limited framework, (iii) further development and testing of data-limited methodologies with specific focus on the review of the current ICES advice framework for stock Categories 4-6, spatial indicators, and reference points for surplus production models, and (iv) other relevant data-limited topics. A survey of participants resulted in a high prioritisation score of four topics of the ICES data-limited roadmap: (1) risk equivalence, best available science, guidelines and communication of data-limited methods, (2) value of information of different data-types and data preparation, (3) better advice for slow-growing species, and (4) observation and parameter uncertainty in empirical harvest control rules and length-based approaches. The current ICES approach for Category 5 and 6 stocks, with an advice for constant annual catch and a periodic reduction with a precautionary buffer, is a form of non-adaptive management and an initial review revealed that it may not be precautionary if a stock is overfished but also overly precautionary in other situations. An exploration of spatial indicators showed that these have the potential to inform on stock status. A stochastic definition of MSY Btrigger for surplus production models takes uncertainty into account and leads to higher reference values than the current definition for stocks with low and intermediate biomass variability.PublishedReferee
Effects of chitosan-microparticles-coating on the quality of vacuum-packed sea bass (Dicentrarchus labrax) fillets during refrigerated storage.
No full textIn this work, a combination of vaccum pachaging and bio-coating by chitosan were used to coat sea bass (Dicentrarchus labrax) fillets in order to delay growth of total mesophilic aerobic bacteria, psychrophilic bacteria during refrigerated storage (22 days). The preservative effect of refrigerated and vacuum-packed seabass (Dicentrarchus labrax) fillets treated at two different percentage doses (0.2% and 0.5% w/w) of co-products of shellfish was evaluated on the basis of microbiological, proximate composition, pH, total volatile basic nitrogen (TVB-N), trimethylamine (TMA), thiobarbyturic acid (TBArs), and fatty acids (FA). Two ways ANOVA and multiple comparisons were applied, factors being storage time and treatment. During refrigerated storage, the treatment with chitosan from separate co-products exhibited more antimicrobial activity and the lowest value of the TVB-N, TMA and TBArs compared to control lots. The bio-coating by 0.5% dose of chitosan preserved quality and the prolonged shelf-life for 10 days longer. Overall, this treatment may open new promising opportunities for the biopreservation of fish products by enhancing the period of storage of refrigerated and vacuum-packed seabass fillets.PublishedReferee
Effect of warming and land use on the community of planktonic ciliate protists.
No full textAnthropogenic actions have contributed significantly to the increase in temperature and the addition of nutrients to aquatic bodies. Among the organisms that make up the aquatic microbiota, ciliated protozoa are able to respond quickly to environmental changes imposed on these systems. Thus, the objective of this work was to experimentally investigate the effects of warming and nutrient enrichment on the patterns of richness, density and species composition of the ciliate community, using mesocosms as a model system. Effects on all attributes studied were produced only by nutrient enrichment, while changes in temperature and detritus concentration did not produce significant changes in the community. It is suggested that the bottom up effect is probably the control mechanism that is prevailing in the structuring of the community of ciliate protists in this study, as the high nutrient load is probably providing greater availability of niches, through food resources, which favor the increase the abundance and richness of protists.Ações antrópicas sempre contribuíram significativamente para o aumento da temperatura e adição de nutrientes em corpos aquáticos. Dentre os organismos componentes da microbiota aquática, os protozoários ciliados são capazes de responder rapidamente às mudanças ambientais impostas nesses sistemas. Desta forma, investigou-se experimentalmente os efeitos do aquecimento e do enriquecimento por nutrientes sobre os padrões de riqueza, densidade e composição das espécies da comunidade de ciliados, usando mesocosmos como sistema modelo. Os efeitos sobre todos os atributos estudados foram produzidos apenas pelo enriquecimento por nutriente, enquanto que as alterações de temperatura e concentração de detrito, não produziram alterações significativas na comunidade. Dentre os múltiplos estressores avaliados, o de maior impacto na estruturação da comunidade de ciliados foi o efeito positivo dos nutrientes sobre a densidade, riqueza e composição de espécies. Destaca-se como resultado do efeito bottom up como mecanismo de controle provável que está prevalecendo na estruturação da comunidade de protistas ciliados.Master
Spatial and temporal beta diversity of fish in a fragmented tropical river.
No full textThe overexploitation of natural resources by human beings in recent centuries has had serious consequences for biodiversity. In freshwater aquatic environments, organisms suffer from various degradation processes, which involve pollution, environmental fragmentation, introduction of invasive species, among others. The construction of dams and reservoirs for energy production is among one of the biggest reasons for the degradation of these environments, as this fragments the water body, preventing connectivity between sites, in addition to transforming the lotic environment into a lentic one, completely changing the dynamics of the local. As an aggravating factor, there are reservoir cascades, which consist of a sequence of reservoirs built on the same river, enhancing the negative effects of a single reservoir. In highly fragmented environments, physical-chemical changes occur, which harm the local biological communities. Thus, in this work, analyzes of the spatial and temporal beta diversity of fish were carried out in a very fragmented river in northeastern Brazil, the São Francisco River. For spatial beta diversity, we calculated the Local Contribution to Beta Diversity (LCBD), taxonomic and functional, at 28 points along the six reservoirs and in a lotic stretch downstream of the reservoirs, up to the mouth. We performed a beta regression model to verify the relationship between LCBD values and environmental variables collected in the same period. As a result, we found that the points of the initial reservoirs and the points closest to the mouth of the river were the ones that most contributed to beta diversity, both taxonomic and functional, and turbidity was the variable that was most positively associated with LCBD values. For the temporal beta diversity analysis, we used five reservoirs, and compared the beta diversity between pairs of months over years. A correlation was also made between the results of temporal beta diversity and the variation of environmental variables. There was no relationship between environmental variables and temporal beta diversity. However, it was possible to observe that the reservoirs that operate as a trickle of water had the most unstable and unpredictable temporal beta diversity values, while the reservoir that operates as an accumulation followed the pattern of seasonal variation of the dry-flood dynamics. We recommend the proper management of the reservoirs of a waterfall, monitoring the variations in the parameters and regulating the flow and water level according to the expected natural variations, mainly the initial ones that function as sources of species and functional traits, and also the preservation of the rivers tax. We conclude that deeper studies covering other periods must be carried out, to complement the existing data and provide greater assertiveness in decision-making and conduction of reservoir operations.A superexploração dos recursos naturais pelo ser humano nos últimos séculos tem trazido graves consequências para a biodiversidade. Em ambientes aquáticos de água doce, os organismos sofrem com diversos processos de degradação, que envolvem poluição, fragmentação do ambiente e introdução de espécies invasoras. A construção de barragens e reservatórios para a produção de energia está entre um dos maiores motivos para degradação desses locais, pois isso fragmenta o corpo hídrico, impedindo a conectividade entre os locais, além de transformar o ambiente lótico em lêntico, mudando completamente a dinâmica do local. Como agravante, existem as cascatas de reservatórios, que consistem em uma sequência de reservatórios construídos em um mesmo rio, potencializando os efeitos negativos de um único reservatório. Em ambientes altamente fragmentados, ocorrem mudanças físico-químicas, o que prejudica as comunidades biológicas locais. Dessa forma, analisou-se a diversidade beta espacial e temporal de peixes, em um rio muito fragmentado no nordeste brasileiro, o rio São Francisco. Para a diversidade beta espacial, calculou-se a Local Contribution to Beta Diversity=Contribuição Local para a Diversidade Beta (LCBD), taxonômica e funcional, em 28 pontos ao longo dos seis reservatórios e em um trecho lótico à jusante dos reservatórios, até a foz. Aplicou-se um modelo de beta regressão para verificar a relação dos valores de LCBD com as variáveis ambientais coletadas no mesmo período. Como resultado obtido, os pontos dos reservatórios iniciais e os pontos mais próximos à foz do rio foram os que mais contribuíram para a diversidade beta, tanto taxonômica quanto funcional, e a turbidez foi a variável que mais se associou positivamente com os valores de LCBD. Para a análise de diversidade beta temporal, utilizou-se cinco reservatórios, e foi feita uma análise comparativa da diversidade beta entre pares de meses ao longo de anos com o Temporal Beta-Diversity Index=Índice de Diversidade Beta Temporal (TBI). Estabeleceu-se uma correlação entre os resultados de diversidade beta temporal e a variação das variáveis ambientais. Não foi observado relação entre as variáveis ambientais e a diversidade beta temporal. No entanto, foi possível observar que os reservatórios que operam como fio d’água tiveram os valores de diversidade beta temporal mais instáveis e imprevisíveis, enquanto o reservatório que opera como acumulação seguiu o padrão de variação sazonal da dinâmica de seca-cheia. Recomenda-se o manejo adequado dos reservatórios de uma cascata, monitorando as variações nos parâmetros e regulando o fluxo e nível de água de acordo com as variações naturais esperadas, principalmente os iniciais que funcionam como fontes de espécies e traços funcionais, e também a preservação dos rios tributários. A aplicação de modernos índices de diversidade beta, como LCBD e TBI, com atributos taxonômicos e funcionais, inédita para o sistema estudado, resultou em informações importantes para a operação dos reservatórios, fornecendo maior assertividade nas tomadas de decisões e condução das atividades dos operadores.Ph