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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
Etude de la pollution par les microplastiques dans les sédiments et les eaux de surfaces au Golfe de Tunis, plages de Ghar El Melh et Chatt Mami.
No full textCes dernières années, la contamination par les microplastiques (MP) est devenue une préoccupation mondiale. Les particules (< 5 mm) représentent de plus en plus une menace globale et persistante pour l'ensemble des écosystèmes. Dans cette étude, l'abondance et les propriétés (taille, forme et type de polymère) des MPs dans les échantillons d'eau de surface de la mer et les sédiments du sable ont été étudiés dans quatre zones côtières de la mer Méditerranée (Golfe de Tunis, îles Pilau et Plane, plage de Ghar El Melh et Chatt Mami). Les îles ont montré l'abondance moyenne des MPs la plus élevée (0,007 à 1,967 éléments/m³), suivi de la plage de Ghar El Melh (0,019 à 0,068 éléments/g), du Chatt Mami (0,012 à 0,057 éléments/g) et du golfe de Tunis (0,009 à 0,053 éléments/m³). Les résultats ont montré que les MPs détectés dans tous les échantillons, indiquant une vaste répartition toute au long de la côte tunisienne. Les MPs représentatifs des quatre sites ont été préparés pour l'identification des polymères par Spectroscopie Infrarouge à Transformée de Fourier (FTIR ATR). Au total, neuf types de polymères ont été détectés (PVC, PET, PP, PE, PS, PA, PVDF et PEHD). Les formes identifiées dans cette étude sont (Fragments, Films, Filaments et Granulés) avec une prédominance des fragments détectés sur la surface de l'eau et les filaments détectés dans les sédiments ainsi qu’une contribution assez faible des granulés. Cette étude a permis donc de générer des données originales sur la présence de MPs dans les sédiments et les surfaces de l'eau côtiers de la côte nord tunisienne.These last years, Microplastic contamination (MP) has become a global concern. Particles (< 5 mm) increasingly represent a global and persistent threat to all ecosystems. In this study, the abundance and properties (size, shape and polymer type) of MPs in sea surface water samples and sand sediments were studied in four coastal areas of the Mediterranean Sea (Gulf from Tunis, Pilau and Plane islands, Ghar El Melh and Chatt Mami beach). The islands showed the highest average abundance of MPs (0.007 to 1.967 elements/m³), followed by Ghar El Melh beach (0.019 to 0.068 elements/g), Chatt Mami (0.012 to 0.057 elements/g) and the Gulf of Tunis (0.009 to 0.053 elements/m³). The results showed that MPs detected in all samples, indicating a wide distribution along the Tunisian coast. Representative MPs from the four sites were prepared for polymer identification by Fourier Transform Infrared Spectroscopy (FTIR-ATR). In total, nine types of polymers were detected (PVC, PET, PP, PE, PS, PA, PVDF and HDPE). The forms identified in this study are (Fragments, Films, Filaments and Granules) with a predominance of fragments detected on the water surface and filaments detected in sediments as well as a low contribution of granules. This study generated original data on the presence of MPs in sediments and coastal water surfaces of the Tunisian north coast.Master
Yemaya No.68, December 2023
No full textYemaya No. 68, dated December 2023, features articles from Costa Rica, Chile, Malawi, Uganda, Nigeria, Tanzania, Ghana and Southeast Asia on Inland fisheries, fisheries management, fish processing, social capital, gendered economy of dried fish, climate change, women in fisheries profile from Africa, and a review of a book on women in small-scale fisheries and aquaculture in Asia. Articles from Costa Rica and Chile show, in cases where government support was made available to facilitate women’s participation in decision making in cooperative fisheries groups, it led to improved earnings for women; better representation of women in leadership; and better environmental outcomes. The case study from Malawi shows how important it is for mainstreaming efforts to go beyond the issue of equitable access to markets for women engaged in fish trade, and to include equity in pricing and returns for both women and men. The study also shows the importance of addressing gender biases in the ways in which women and men perceive discrimination. When women’s work receives focused attention, the importance of their contributions to the sector is duly revealed. Several research projects on mapping dried fish presented at the GAF-8 Conference in Kochi in November 2022, shed light on the substantial contributions made by women fishers in postharvest processing and trade. The article from Tamil Nadu in India shows how in families, forced to migrate to larger cities due to dwindling economic opportunities in their native villages, women play significant and cohesive roles within the migrant community, often facilitating financial upscaling and social stability. In the interview with Edithrudith Lukanga, Secretary General of AWFishnet and Technical Advisor at EMEDO, she argues that the challenges women facing are similar across the world but they are contextual. If there are national platforms, then they can amplify their united voice. The Profile column by Peter L.A. looks at how Lydia Sasu became a community leader in Ghana and her work in organizing women in small-scale fisheries in Ghana has received international recognition. In What’s New, Webby? Vishakha Gupta looks at how CAOPA, The African Confederation of Professional Organizations of Artisanal Fisheries launched an exciting new series on its website that captures the stories, lives, struggles, challenges and achievements of women leaders in African fisheries. The Milestones column by Ahana Lakshmi looks at the recently published, Taking Stock: Sexual and Reproductive Health and Rights in Climate Commitments: A Global Review and focuses on one key concept –impact. The article highlights the fact that the existing structural drivers of inequality in society are often a tangled web causing non-uniform impacts. Veena N. in the Yemaya Recommends section, points out that the book, Women and Men in Small-scale Fisheries and Aquaculture in Asia seeks to inquire into the forms and implications of gender -based division of labour, analyse the drivers of these differences, and identify entry points and opportunities for addressing inequalities and discriminatory practices. The current issue of Yemaya also carries the ever-popular cartoon strip, “Yemaya Mama”(“This type of smoking is safe and profitable!”).PublishedReferee
Результаты исследования промысловых видов рыб в Веселовском водохранилище в 2021–2022 гг.
No full textThis article presents the results of fish resource assessment conducted in 2021–2022 in the Veselovsky Reservoir and characterizes its major commercial fish species. The results of the investigation of the commercial fish stocks in the Veselovsky Reservoir characterize the physiological status of the populations as good based on a number of parameters (visceral fatness, conditional factor, fertility), which results from the abundance and diversity of the food supply and favorable environmental conditions. In the past two years, a noticeable increase in the stock abundance of commercial fish species has been observed in the Veselovsky Reservoir, which provides the ground to expect the formation of a stable resource for commercial fishing in the near future.В статье приведены результаты сырьевых исследований, выполненных в 2021–2022 гг. в Веселовском водохранилище. Дана характеристика основных промысловых видов рыб. Результаты проведенных исследований состояния запасов промысловых рыб в Веселовском водохранилище свидетельствуют о хороших физиологических характеристиках рыб (высокие показатели ожирения внутренностей, коэффициентов упитанности, плодовитости), обусловленных обилием и разнообразием кормовой базы и благоприятными условиями среды обитания. В последние два года в Веселовском водохранилище наблюдается заметное увеличение запасов промысловых видов рыб, что позволяет прогнозировать создание устойчивой базы для промышленного рыболовства в ближайшем будущем.PublishedNon Referee
Качественный и количественный состав углеводородов донных отложений северо-восточной части Карского моря
No full textThe surface layer (0–5 cm) of the bottom sediments, which samples were collected during the expedition of the RV “Academician Boris Petrov” in the Northeastern Kara Sea in the summer of 2022, has been investigated. Data on the content and composition of hydrocarbons (HCs) in the bottom sediments of the investigated aquatic area have been obtained. Since oil and petroleum products are among the most common sources of pollution of the seas and oceans, it is necessary to conduct regular surveys of marine ecosystems. This work is aimed at a qualitative and quantitative assessment of HCs in the bottom sediments of the Northeastern Kara Sea and identification of their possible sources. Examination of the qualitative and quantitative composition of HCs was carried out by gas chromatography using the gas chromatograph "Crystal-5000.2" with a flame ionization detector. The quantitative determination of the total HC content was conducted by the method of absolute calibration of the FID using a mixture of HCs prepared by the gravimetric method. Chromatec Analytic 3.0 software was used to process the results. It has been found that the total amount of HCs in the bottom sediments of the Northeastern Kara Sea ranged from 25.8 to 152.4 mg/kg, being 68.21±7.76 mg/kg on average. Based on analysis of the chromatograms, the predominance of high-molecular fractions has been identified; the maximum distribution of n-alkanes was represented by homologous compounds n-C25–C29, which are the markers of allochthonous organic matter. After comparison with the calculated diagnostic indices (CPI1, CPI2, ACL, LWH/HWH, TAR, C31/C29, Paq, TMD, ΣC25–35/ΣC15–21, Pr/Ph), it was found that the increased concentrations of HCs mainly result from the natural processes and prevalence of allochthonous organic matter in bottom sediments.Проведены исследования поверхностного слоя донных отложений (0–5 см) северо-восточной части Карского моря, отобранных в рейсе НИС «Академик Борис Петров» летом 2022 г. Получены данные о содержании и составе углеводородов (УВ) в донных осадках исследуемой акватории. Поскольку нефть и нефтепродукты являются одним из самых распространенных источников загрязнения морей и океанов, необходимо проводить регулярный мониторинг морских экосистем. Целью данной работы является качественная и количественная оценка УВ в донных отложениях северо-восточной части Карского моря и определение вероятных источников их происхождения. Определение качественного и количественного состава УВ производилось методом газовой хроматографии на хроматографе «Кристалл 5000.2» с пламенно-ионизационным детектором. Количественное определение суммарного содержания УВ проводили методом абсолютной калибровки ПИД с помощью смеси УВ, приготовленной гравиметрическим методом. Для обработки результатов использовали программное обеспечение «Хроматэк Аналитик 3.0». Установлено, что общее количество УВ в донных отложениях северо-восточной части Карского моря варьировало от 25,8 до 152,4 мг/кг, в среднем составляя 68,21±7,76 мг/кг. По анализу хроматограмм отмечено преобладание высокомолекулярных фракций; максимальное распределение н-алканов приходилось на гомологи н-С25–С29, которые являются маркерами аллохтонного органического вещества. При сопоставлении с рассчитанными диагностическими индексами (CPI1, CPI2, ACL, LWH/HWH, TAR, C31/C29, Paq, TMD, ΣС25–35/ΣС15–21, Pr/Ph) установлено, что повышенные концентрации УВ в основном обусловлены природными процессами и преобладанием аллохтонных органических веществ в донных осадках.PublishedReferee
Building the Blue Innovation Pipeline: Lessons Learned from the United States and Sweden.
No full textWhile there are many exciting innovations taking place in the “blue” (water-based) economy, the findings of this study indicate that more investment in research and development (R&D) is economically justified. In fact, blue R&D is underfunded by at least 112% compared to worldwide benchmarks. Even if an additional 30-50B (billion) in global funding for R&D reduced the future risks of water environments and increased the economic rewards of water-based industries by just 10%, this would still deliver 183B worth of economic benefit and enhanced environmental protection.Please also add as Activity to challenges 5 and 9PublishedNot Know
MONITOR: Mitigation of Natural Incidence Towards an increased Oceanic Resilience [Poster]
No full textThe proposed project will make contributions to marine natural disaster prevention of countries in the Indo-Pacific region. The project will have major focus on education and intelligent collaborations among young scientists. There will be summer course being offered to students from all participating institutions every year, together with personnel exchange program. The technology for developing regional physical-biological modeling will be introduced and the operational forecasting systems for regional environments are expected to be developed in the coastal regions along the Indian and western Pacific Ocean.Unpublishe
Сырьевая база промысловых беспозвоночных в Азовском море и динамика ее освоения в 2000–2022 гг
No full textIn the context of a low water conent in the Azov Sea along with an increase in its salinity and the background temperature, a decrease in the stocks of stenohaline species of bioresources and an expansion of the species composition of halotolerant species are observed; out of the latter ones, the populations of commercial invertebrates are presently characterized by a drastic increase in their stock abundance and biomass. Upon the development of an increased salinity regime of the Azov Sea, it becomes relevant to monitor the undergoing fundamental changes in the exploitable resources of commercial invertebrates. The aim of this work has been to assess the resource potential of commercial invertebrates for the period 2000–2022 and make a forecast of its dynamics under various salinity conditions of the Azov Sea up to 2030. Analytical data characterizing the status of the exploitable resources of commercial invertebrates in the Azov Sea were originally collected during expeditionary surveys in 2000–2022. To characterize the Azov Sea stocks of commercial invertebrates, standard methods of collecting and analyzing the field samples indicative of the state of their populations have been used. A retrospective analysis of the species composition of commercial invertebrates in the Azov Sea indicates an expansion of the list of commercial species, an increase in their stocks and catch volumes, as well as the potential for further additions to the list of commercial species by involving new ones, currently not targeted by fisheries. The development of the invertebrate fishery creates a crucial alternative to the deteriorated catches of commercial fish species and may facilitate the preservation of a small fishing fleet in the Azov Sea, preventing its decline. In the case if salinity remains in the 14.5–16.5 ‰ range or increases to 18.5 ‰, there will be maintained the favorable conditions for increasing the catches of molluscs (veined rapa whelk, mussels, unequal arc), crustaceans (shrimps, Gammarus, Artemia), insects (chironomids), and jellyfish.В условиях маловодности при росте солености и повышении температурного фона воды в Азовском море отмечается снижение запасов стеногалинных видов биоресурсов и расширение видового состава галотолерантных видов, из которых популяции промысловых беспозвоночных в современный период характеризуются интенсивным ростом численности и биомассы запасов. Актуальным является вопрос мониторинга кардинальной перестройки сырьевой базы промысла в условиях формирования режима повышенной солености Азовского моря. Целью работы стала оценка ресурсного потенциала промысловых беспозвоночных за период 2000–2022 гг. и прогноз его динамики при различных условиях солености Азовского моря до 2030 г. Аналитические материалы, характеризующие состояние сырьевой базы промысловых беспозвоночных в Азовском море, подготовлены по данным экспедиционных исследований за период 2000–2022 гг. Для характеристики состояния запасов промысловых беспозвоночных в Азовском море использованы стандартные методики сбора и анализа полевых материалов, характеризующих состояние их популяций. Ретроспективный анализ видового состава промысловых беспозвоночных в Азовском море свидетельствует о расширении перечня промысловых видов, росте объемов сырьевой базы и объемов вылова, а также потенциальной возможности дальнейшего расширения состава промысловых видов за счет вовлечения новых, ранее не используемых промыслом. Развитие промысла беспозвоночных создает необходимую альтернативу выпадающей части уловов промысловых рыб и может способствовать сохранению малого рыбопромыслового флота в Азовском море и предотвращению его упадка. При нахождении солености в диапазоне колебаний 14,5–16,5 ‰ и ее росте до уровня 18,5 ‰ сохранятся благоприятные условия для увеличения объемов вылова моллюсков (рапана, мидии, скафарка) и ракообразных (креветки, гаммарус, артемия), а также насекомых (хирономиды) и медуз.PublishedReferee
Next Generation EV Batteries Eliminate the Need for Deep Sea Mining.
No full textAdvances in electric vehicle (EV) battery technology, and the accelerating adoption of these technologies, are leading to the replacement of EV batteries dependent on cobalt, nickel, and manganese. As a result, the deep sea mining of these metals is neither necessary, economically advantageous, or environmentally advisable. In fact, efforts to promote the mining of these metals in the deep ocean now serve neither manufacturers nor consumers, but only enterprises that have been established for the express purpose of deep sea mining. Typically, companies and consumers are asked to make sacrifices for the good of conservation and the environment. Now, happily, what is good for both enterprise and the end consumer, also serves the need to protect and preserve our oceans, and the life that resides within.PublishedNon Referee