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Comparative study on the composition and functional properties of chitin/chitosan extracted by new combined bioprocess.
No full textBio-extraction of chitin is a greener and eco-friendly process than the conventional chemical method. Taking shrimp waste of Pandalus borealis recovered from plant as a model, two methods were applied for chitin extraction; a chemical and a yeast-based processes (Ch-C and Ch-B respectively). The recovered chitins and chitosan were tested for their biochemical and functional properties. Compared to commercial chitin, both lots, have similar chitin recovery (~26%) and physiochemical properties with ash<1%, protein <10%, with degrees of acetylation (DA) varying 70-80%. However, chitosan obtained from Ch-B lot showed significantly lower molecular weight (MW) and DA (MW: 6.34 KDa, DA: 23.4%) than that found in Ch-C chitosan (MW: 11.36 KDa, DA: 33.4%). The new method proved to be efficient for the production of chitosan of good quality which allowed the elaboration of the membrane.PublishedReferee
First Record of the tropical seagrass Halophila stipulacea (Forsskål) Ascherson, 1867 in the Punic Port of Carthage-Salammbô (Northern Tunisia).
No full textThe bioinvasion has increased in recent years with climate change, and some invasive species have caused significant damage to the marine ecosystem, including a great loss of biodiversity. The studied seagrass is a marine tropical phanerogam introduced in the Mediterranean at the end of the 19th century and in southern Tunisia in 2003. In this study we record this species for the first time in northern Tunisia, precisely in the Punic Port of Carthage-Salammbo. Surveys were carried out on foot around the Punic Port, and measurements/photos were taken on site, and others in the laboratory on taken samples. Most of these measures do not differ from those carried out elsewhere in the Mediterranean. For the moment, the plant does not occupy a large part of the port buttom, but it may invade all the area in the future.PublishedReferee
Таксоцен Polychaeta в прибрежной акватории озера Донузлав
No full textThis work is based on the data collected during the benthic survey of soft sediments in the coastal area of Lake Donuzlav conducted in August, 2020. The current status of the species composition of polychaetes in Lake Donuzlav was investigated. The samples were collected using a manually operated grab sampler with a capture area of 0.04 m2 at the depths from 1 to 8 m. The following indicators were used to describe the quantitative development of benthos: abundance, biomass, occurrence, density index, and Czekanowski–Sørensen index. A total of 31 species of polychaetes have been found. The average values of polychaetes abundance and biomass in the investigated area were 239±51 ind./m2 and 1.537±0.599 g/m2, respectively. The main contribution to the total abundance is made by Spio decorata, and to the total biomass by Lagis neapolitana. The largest number of species and the highest abundance were recorded at the depths of 1.1–2 m. The largest biomass was recorded at the depths of 6.1–7 m. The ranked series according to the density index is headed by L. neapolitana, Glycera tridactyla, and S. decorata. The trophic structure of polychaetes is represented by poly-, phyto-, detritophages, carnivores, and the animals, the food spectrum of which has not been studied. The most widely represented group is carnivores; it comprises 10 species of polychaetes. The least number of species (1) was recorded for phytophages. Over 1990–2020, 73 species of polychaetes were identified; they belonged to 29 families and 56 genera.В основу работы положены результаты бентосной съемки рыхлых грунтов в прибрежной акватории озера Донузлав, выполненной в августе 2020 г. Исследовано современное состояние видового состава полихет озера Донузлав. Сбор материала проводили ручным дночерпателем площадью захвата 0,04 м2 на глубинах от 1 до 8 м. Для описания количественного развития бентоса применены следующие показатели: численность, биомасса, встречаемость, индекс плотности и коэффициент Чекановского–Серенсена. Всего обнаружен 31 вид полихет. Средний показатель численности полихет по всему району исследования составил 239±51 экз./м2, средний показатель биомассы — 1,537±0,599 г/м2. Основной вклад в общую численность вносит Spio decorata, в общую биомассу — Lagis neapolitana. Наибольшее количество видов отмечено на глубинах 1,1–2 м. Наибольшая численность отмечена на этих же глубинах. Наибольшая биомасса зарегистрирована на глубинах 6,1–7 м. Ранжированный ряд по индексу плотности возглавляют L. neapolitana, Glycera tridactyla и S. decorata. Трофическая структура представлена поли-, фито-, детритофагами, плотоядными и животными, пищевой спектр которых не изучен. Самая многочисленная группа — плотоядные, к которой принадлежат 10 видов полихет; наименьшее количество видов (1) отмечено в группе фитофагов. За период с 1990 по 2020 г. обнаружено 73 вида полихет, принадлежащих к 29 семействам и 56 родам.PublishedReferee
Прогноз динамики первичной продукции органического вещества и загрязнения приоритетными токсикантами Азовского моря на краткосрочную перспективу
No full textModern climate changes and increasing anthropogenic water withdrawal in the Azov Sea river basins have led to a reduction in freshwater runoff and a record increase in the sea salinity. Salinization of the Azov Sea leads to a transformation of the structure of biological communities and a decrease in primary productivity, which inevitably has a negative impact on fish productivity. Another important factor in the stock formation of aquatic biological resources is the quality of their habitat. Aim of this work is to make a short-term forecast of the hydrochemical foundation of biological productivity and toxicological status of the Azov Sea up to 2030. This study was based on the long-term data on the level of primary production, hydrochemical regime and accumulation of priority toxicants in the Azov Sea ecosystem. In the present period, adaptation of the Azov Sea ecosystem to increasing water salinity is manifested in a decrease in the level of primary production. In recent years, during the summer season, an unfavorable physiological state of phytoplankton has been observed due to the high content of pheophytin in the cells. In the Azov Sea, from 1986 (the peak of industrial development and anthropogenic load) up to the present, in the water, bottom sediments and muscles of commercial fish species, has been observed a decrease in the average annual concentration of the majority of monitored toxicants. Under the most likely forecasted scenario for the river flow and water salinity (14.5–16.5 ‰), a further decrease in the level of primary production is expected. It is possible that the ecosystem will adapt to the increase in water salinity; phytoplankton will be characterized by a more favorable physiological state in the summer. No deficiency of biogenic elements is predicted. If the existing anthropogenic load remains unchanged (the most likely scenario), the level of sea pollution by anthropogenic toxicants is predicted to be low, and in certain areas — Taganrog Bay, the waters of the Yeysk and Temryuk Sea Ports — it is expected to be moderate. The quality and safety of aquatic biological resources as a food product will meet regulatory requirements.Современные климатические изменения и увеличение объема хозяйственного изъятия вод в бассейнах рек Азовского моря привели к сокращению пресноводного стока и рекордному росту солености моря. Осолонение Азовского моря приводит к трансформации структуры биологических сообществ и снижению первичной продуктивности, что неизбежно негативно отражается на рыбопродуктивности. Другим важным фактором формирования запасов водных биологических ресурсов служит качество среды обитания. Цель работы — дать прогноз гидрохимических основ биологической продуктивности и токсикологической ситуации в Азовском море в краткосрочной перспективе до 2030 г. Материалами для исследования явились многолетние данные по уровню первичной продукции, гидрохимическому режиму и накоплению приоритетных токсикантов в экосистеме Азовского моря. В современный период адаптация экосистемы Азовского моря к росту солености воды проявляется в снижении уровня первичного продуцирования. В последние годы в летний период отмечается неблагоприятное физиологическое состояние фитопланктона за счет высокого содержания в клетках феофитина. В Азовском море с 1986 г. (пик развития промышленности и антропогенной нагрузки) к настоящему времени в воде, донных отложениях и мышцах промысловых видов рыб отмечено снижение среднегодовой концентрации большинства контролируемых токсикантов. При наиболее вероятном сценарии прогноза речного стока и солености воды (14,5–16,5 ‰) ожидается дальнейшее снижение уровня первичной продукции. Возможно, произойдет адаптация экосистемы к росту солености воды и фитопланктон будет характеризоваться более благоприятным физиологическим состоянием в летний период года. Дефицита биогенных элементов не прогнозируется. При сохранении существующего уровня антропогенной нагрузки (наиболее вероятный сценарий) уровень загрязнения моря антропогенными токсикантами прогнозируется как низкий, а в отдельных районах — Таганрогский залив, акватория Ейского и Темрюкского морских портов — как умеренный. Качество и безопасность водных биоресурсов как продукта питания будут соответствовать нормативным требованиям.PublishedReferee
Искусственное воспроизводство полупроходных видов рыб при разных сценариях развития гидрологической обстановки в Азовском море
No full textSemi-anadromous fish species of the Azov Sea were the primary fishing targets before the regulation of the flow of the Don and Kuban Rivers, after the anthropogenic transformation of which artificial reproduction became the main source of recruitment for the populations of these species of aquatic biological resources. Unprecedented climate-induced reduction in the volume of freshwater runoff in 2006–2023 aggravated the deterioration of the conditions for reproduction of anadromous fish species in the aquatic areas associated with fish feeding and rearing facilities and contributed to the decline of their feeding conditions in the sea resulting from a sharp increase in salinity, which led to a reduction in their population abundance. Relevance. In the context of a record reduction in freshwater runoff and increasing salinity of the Azov Sea, the Azov Sea ichthyocenosis undergoes a fundamental restructuring, which requires making a forecast of the possible changes in the habitat of semi-anadromous fish species, as well as evaluating the prospects for artificial reproduction of zander, roach and bream for their preservation in new conditions, which, in turn, serves as the aim of this work. To predict possible changes in the hydrological regime of the Azov Sea, the expert evaluation method has been used. The expert assessment of possible scenarios of the impact exerted by the modern climate change on the habitat of the aquatic biological resources in the Azov Sea has been done with the regard to the provisions of the Climate Doctrine of the Russian Federation. Under all predicted scenarios for the period up to 2030, the salinity of the Azov Sea will exceed the values optimal for the juveniles and mature individuals of semi-anadromous fish species. Preservation of biologically valuable populations of zander and roach is possible with the continuous operation of hatcheries (spawning and rearing facilities), both in limans and on floodplain. To preserve the population and increase the stock of bream, it is necessary to restore artificial reproduction of this species. In the medium term (until 2030), only roach has a prospect for the sufficient recovery of its stocks, which could happen under the favorable hydrological scenario involving the water content increase in the basin. In all other cases, bream, zander and roach will not be in position to considerably increase their abundance.Полупроходные рыбы Азовского моря являлись базовыми объектами рыболовства до зарегулирования стока рек Дон и Кубань, после антропогенного преобразования которого основным источником пополнения популяций рассматриваемых видов водных биоресурсов стало искусственное воспроизводство. Беспрецедентное климатообусловленное сокращение объема пресного стока в период 2006–2023 гг. усилило нарушение условий воспроизводства полупроходных видов рыб на акваториях нагульно-выростных хозяйств и ухудшило условия их нагула в море из-за резкого роста солености, что привело к сокращению численности популяций. В условиях рекордного сокращения пресного стока и роста солености Азовского моря происходит кардинальная перестройка его ихтиоценоза, что требует разработки прогноза динамики возможных изменений условий обитания полупроходных видов рыб, а также определения перспектив искусственного воспроизводства судака, тарани и леща для их сохранения в новых условиях, что, в свою очередь, является целью настоящей работы. Для прогнозирования возможных изменений гидрологического режима Азовского моря применялся метод экспертного оценивания. Экспертная оценка возможных сценариев воздействия современных климатических изменений на условия среды обитания водных биологических ресурсов Азовского моря разработана с учетом положений Климатической доктрины Российской Федерации. При всех прогнозируемых на период до 2030 г. сценариях соленость Азовского моря будет превышать значения, оптимальные для обитания молоди и половозрелых особей полупроходных видов рыб. Сохранение ценных с биологической точки зрения популяций судака и тарани возможно при поддержании функционирования нерестово-выростных хозяйств как пойменного, так и лиманного типов. Для сохранения популяции и увеличения запаса леща необходимо восстановить искусственное воспроизводство этого вида. На среднесрочную перспективу до 2030 г. возможность ощутимого восстановления имеет только тарань при условии реализации оптимистичного гидрологического сценария с увеличением водности бассейна. Во всех остальных случаях лещ, судак и тарань до 2030 г. не имеют возможности существенно увеличить свою численность.PublishedReferee
Yemaya No.67, August 2023
No full textYemaya No. 67, dated August 2023, a special issue on GAF8 features articles on the recently held 8th Global Conference on Gender in Aquaculture and Fisheries-Shaping the Future: Gender Justice for sustainable aquaculture and Fisheries. Held over three days, from 21-23 November 2022 in the city of Kochi in the coastal state of Kerala in India, GAF8 attracted 198 delegates from 26 countries and hosted 70 paper presentations as well as a range of expertly curated audio-visual media events. The presentations at the conference revealed that women in aquaculture and fisheries across the world are putting in long hours of hard labour in conditions that are becoming increasingly more challenging due to climate change impacts and the growing risk of biological and environmental disasters. The dire and long-overdue need for formal recognition of women’s labour emerged as one of the chief recommendations from the conference. Other recommendations include women’s rights of tenure and the management and use of coastal lands; women’s right to receive institutional support and build capacity and entrepreneurship; to have access to food and nutritional security; to live and work in a safe, peaceful and hygienic environment; and to collectivize and organize themselves. Another key recommendation is the need for new approaches to document and analyse gender issues in aquaculture and fisheries, which draw upon political economy, human rights, intersectionality, and transformative, participatory, and gendered value chain concepts, and include standardized tools and methodologies to generate gender-based data. The Profile column by Ashwini Jog looks at how Purnima Meher continues her struggle for the rights of fisherwomen who are facing increasing marginalization due to large-scale development projects that encroach the seas and coastal areas, depriving the fishing community of their primary means of livelihood. The current issue of Yemaya also spotlights Coast 2 Coast which contains information distilled from the collaborative work of a Peruvian community based nonprofit with rural educators and young leaders from public schools, nonprofits and social welfare centers located in inland and coastal small-scale fishing villages in Peru, Nigeria, Madagascar and India. Emi opines that this curriculum would be of great value, especially for the purpose of advocacy and training. The Milestones column by Sivaja Nair looks at the recently published Global Gender GAP Report 2023. The report highlights persistent gender disparities that hinder progress towards a more inclusive and equitable society. She argues that women’s representation in leadership roles and their participation in the workforce remain areas of concern. The Yemaya Recommends section, points out that the book “Achieving Gender Equality at Work” offers a series of comprehensive recommendations aimed at achieving gender equality at work. By addressing the identified challenges and adopting the provided recommendations, societies can create more inclusive and sustainable economies that capitalize on the full potential of both women and men.PublishedReferee
Evaluation de degrés de contamination bactérienne des produits de la pêche (points de vente) dans la région de Bou-Ismail et de Khemis Miliana.
No full textNotre étude a pour but d'évaluer l'effet des traitements post-capture (transport et hygiène) sur la qualité des produits de la pêche vendus au marché de Bou-Ismail comme région côtière et de Khemis Miliana comme région interne. L'étude s'est déroulée du mois d'Avril au mois de Juillet 2013. La méthodologie utilisée est celle d'une évaluation de la qualité organoleptique et microbiologique. Cette évaluation a été investiguée pendant la vente dans les deux régions. Les résultats de l’évolution des différents germes obtenus ont été comparés selon la région de prélèvement, l’espèce étudiée et la période du prélèvement. L'évaluation organoleptique et bactériologique indique que les poissons de Bou-Ismail (la Sardine et la Crevette) ont une bonne qualité et une très bonne fraicheur, alors que le Rouget a une qualité satisfaisante, en comparaison avec celles de Khemis Miliana qui ont une qualité satisfaisante et une fraicheur modérée, donc une diminution de la qualité au niveau de la région interne par rapport à la région côtière. Cependant, les poissons analysés sont exempts de germes potentiellement pathogènes tels que Salmonella sp.Références bibliographiques, Tableaux, Figures.PublishedReferee
Brine shrimp provides a rich-high energy food for migrating birds: A case study of an artificial pond in Basrah, Iraq.
No full textA case study focusing on the attraction of migrating birds by brine shrimp (Artemia franciscana) into an artificial pond in Basrah, Iraq. A dump area had constructed at the intertidal mudflat’s zone of Khor Al-Zubair Channel, Basrah, Iraq. Basra Gas Company implemented a dredging operation to increase the channel depth in 2019 to use the dump area as a disposal place for the company’s benthic sediments, which are usually mixed with seawater, converting the dump area to a large hypersaline artificial pond. Unexpectedly, the pond became a habitat for many shorebird species a few months later. The pond has been surveyed five times between March 2019 and January 2020. For each survey, frequent environmental and biological events were observed. Due to high temperature during most summer months (30-50°C), the water level decreased dramatically to (< 0.5 m), which ultimately led to increase levels of salinity in the pond (80 psu). Moreover, growth of blue-green algae was observed and appearance of brine shrimp A. franciscana. During autumn and winter surveys, an abundance of live A. franciscana and their cysts was observed. Birds appeared to forage primarily on A. franciscana in the pond. The abundance of brine shrimp attracts migrating birds to exploit this prey. 11 species of migrating birds were detected in the pond. These species were flamingo Phoenicopterus ruber, flocks of avocet Ricurvirosta avosetta and Shelduck Tadorna tadorna. Therefore, this site with abundant food resources could provide a rich-high energy food for migrating birds and staging area for a long flight.PublishedReferee
Использование науплий рачков Artemia salina в качестве носителя пробиотиков бактерий рода Bacillus в аквакультуре
No full textThis paper presents the results of the investigation of the effect of probiotic preparations based on Bacillus strains on Artemia salina nauplii. The use of live food is a necessary step in cultivation of many fish species, and Artemia nauplii are widely used for this purpose. It is crucial to use probiotics in aquaculture, as they can act as natural antagonists of aquatic pathogens, as well as stimulate fish growth and development. This work aims to study the immobilization of probiotic Bacillus strains on Artemia nauplii in order to develop highly effective feeds with probiotic properties for juvenile fish. Experiments on the introduction of various doses of preparations based on three probiotic strains of Bacillus into the water during the rearing of Artemia salina cysts were carried out. The number of bacteria in the water, as well as on the surface and inside the nauplii, was estimated by plating on nutrient media. It has been established that, despite the fact that brine shrimps do not feed at the orthonauplius stage, when probiotic strains are introduced into the water, bacteria are immobilized on the covers of the crustaceans; the concentration of the introduced Bacillus strains in the wipe samples taken from the nauplii surface is 1 order higher than it is for the planktonic form in the water. The introduction of bacilli at a dose of 0.0017 g/L activated the release of nauplii from cysts by 9–41 % of the control, while increasing the dose to 0.17 g/L led to a decrease in the proportion of hatched crustaceans. Thus, if the correct dosage were identified, it would make it possible to accomplish two important tasks at once: to obtain the live feed with probiotic properties for fish larvae and to increase the yield of nauplii.В работе представлены результаты исследования влияния пробиотических препаратов на основе бактерий Bacillus на науплий рачков Artemia salina. Использование живых кормов является необходимым этапом при разведении многих видов рыб, и науплии артемии широко применяются для этой цели. Весьма актуально применение в аквакультуре пробиотиков, которые могут выступать как естественные антагонисты патогенов гидробионтов, а также стимулировать их рост и развитие. Целью данной работы являлось изучение иммобилизации пробиотических штаммов Bacillus на науплиях артемий для разработки высокоэффективных кормов для молоди рыб, которые бы обладали пробиотическими свойствами. Проведены эксперименты по внесению различных доз препаратов на основе трех пробиотических штаммов Bacillus в воду при выращивании цист Artemia salina. Оценивалась численность бактерий в воде, а также на поверхности и внутри науплий методом посева на питательные среды. Установлено, что несмотря на то, что на стадии науплии артемии не питаются, при внесении в воду пробиотических штаммов происходит иммобилизация бактерий на покровах рачков; при этом концентрация внесенных штаммов бацилл в смывах с науплий на 1 порядок выше, чем находится в воде в планктонной форме. Внесение бацилл в дозе 0,0017 г/л активизировало выход науплий из цист на 9–41 % от контроля, тогда как повышение дозы до 0,17 г/л приводило к снижению доли вылупившихся рачков. Таким образом, при условии правильного подбора дозировки препарата можно добиться решения сразу двух задач: получения живых кормов с пробиотическим эффектом для личинок рыб и увеличения выхода науплий.PublishedReferee
PICES Press, Vol. 31, No. 2, Summer 2023
No full textIntersessional Science Board Meeting 2023 - Note from the new SB Chair. Future SSC's 9th Intersessional Meeting ~Highlights. PICES 2023 ~ See you in Seattle. The 5th International Conference on the Effects of Climate Change on the World's Ocean ECCWO5 (Together we will work; W1 Workshop Report; W2 Workshop Report; S2 Session Report; S3 Session Report; S10 Session Report; S18 Session Report; S19 Session Report; ECOP Update; Presentation Awards; EuroFish). PICES-MAFF Ciguartera Project - Summary of Activities. Exploring National ECOP hubs in PICES member countries. The 44th Pacific Ecology and Evolution Conference (PEEC). Regional Reports (The Bering Sea: Current Status and Recent Trends; Western North Pacific - Current Status and Updates: Sea surface temperatures for the 2022/2023 cold season; The Northeast Pacific: Update on marine heatwave status and trends). The Continuous Plankton Recorder as a platform for sensor development. ICES Annual Science Conference, 2022: Theme Session J. The Development of the SUPREME Network. Remembering Vera Alexander. PICES by the Numbers: #ECCWO5 Calculated Carbon Emissions. PICES Events Calendar. Your PICES Science Images. Open call for PICES Press submissions|About PICES PressPublishedNon Referee