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Scale characteristics of the bloom event: A case study in the Iranian coastal waters of the Southern Caspian Sea
Get PDFNutrient enrichment in water and sediments due to excessive anthropogenic activities in recent years has caused excessive algal growth in the Caspian Sea. The current study was conducted to determine the abundance of phytoplankton community, the dominant species and chlorophyll-a [Chl-a] concentration during algal blooms in the Iranian coastal waters of Caspian Sea through four seasons from 2013 to 2014. The minimum and maximum phytoplankton abundance recorded were 73±31 and 505±55 million cells m-3 in summer and winter, respectively. The median concentration of Chl-a increased to 5.81 mg m -3 in autumn, as compared to the annual median value (2.43 mg m^-3 ). The results indicated that the bloom started in autumn and it continued falling with a low concentration during winter (Chl-a: 2.59 mg m^-3). The three species Stephanodiscus socialis, Binuclearia lauterbornii and Thalassionema nitzschioides were classified in medium bloom class (100-1000 million cells m^-3) in spring, summer and autumn, respectively. While in winter Pseudonitzschia seriata (harmful species) and Dactyliosolen fragilissima were classified in medium bloom class with high relative frequency. The scaling of bloom abundance revealed that bloom initiation coincided with 10 million cells m^-3 of the dominant phytoplankton species. The bloom at the regions with more than 100 million cells m^-3 of total phytoplankton abundance and dominant species was overlapped with the bloom regions based on Chl-a concentration
The synergistic influence of Holothuria arenicola extract and imidazole carboxamide on Cellosaurus cell line B16-F10
Get PDFSkin cancer has been reported as a contemporary malignant cancer. Here, anti-cancer effects of sea cucumber extract (SCE) from Holothuria arenicola have been examined on melanoma cells and compared with imidazole carboxamide (Dacarbazine) as a chemotherapy medication against melanoma and Hodgkin's lymphoma. MTT assay and morphological analysis were performed to evaluate cytotoxic effects of H. arenicola extract. Also, several methods were exerted to detect cell dying by SCE and imidazole carboxamide. The MTT assay showed that B16F10 cells proliferation was blocked by SCE (IC_50=31µg ml ^-1) and imidazole carboxamide (IC_50=1600 µg ml ^-1) in a dose and time dependent manner. Apoptosis induction yield treatment occurred at IC50 concentration of SCE and imidazole carboxamide using DAPI staining, Acridine orange/Propodium iodide, PI flow cytometry and annexin/PI assay. The caspase colorimetric kit indicated that SCE and imidazole carboxamide could induce apoptosis through an intrinsic pathway. Collectively, our findings suggested that the methanolic SCE has more efficient cytotoxicity efficiency compared to imidazole carboxamide. Therefore, SCE may be considered as a futuristic marine natural product regarding prevention or treatment of melanoma malignancy
Benthic assemblages for ecological evaluation of Bardawil Lagoon, Mediterranean Sea, Egypt
Get PDFBardawil Lagoon is the only highly saline oligotrophic lagoon in Egypt, has an area of ca. 650 km2 with water depths ranged 0.3m to 3m and economically important in terms of fish production. It is the optimum zone getting migratory birds in winter. It is separated from the Mediterranean Sea by a narrow sandy shelf (90 km length, and 22 km width). Ecological evaluation of benthic communities in Bardawil Lagoon to follow-up study of the distribution of benthic study at 12 selected sampling sites representing different environmental habitats for long periods through the project of Environmental Study Wetlands OF North Egyptians Lakes where samples were collected seasonally (2010-2015) and semi-annually (2015 - 2019). The results and data analysis indicated that the distribution, composition and dominance of macro benthic organisms in Lake Bardawil were composed mainly of Ostracoda, Polychaeta, Sea grasses, Bivalvia, Insecta larvae communities and dominated the constituent of bottom fauna. The variations in the benthic biomass were the heaviest at sites elRaodh and meddle elRaodh representing 1354 and 1105 g/m2 which corresponding respectively to 18.2 % and 14.9% of the annual average of benthic biomass (619 g/m2). Regional variations abundance of the benthic structure was highest at sites elTelol and elRaodh representing 3486 ind/m2 and 3635 ind/m2 which corresponding respectively to 14.8% and 15.3% of the annual average of benthic density (1978 ind/m2). Sites of sampling study were evenly spread (J’ > 0.8) at most sites except at elTelol and elRaodh also, high diversity (H’ > 3.00) was at the most sites and show lower value at sites elTelol, elGals, Boughaz I, elNaser, and Raba`a while, Swartz Dominance indexes of number of 5 species over 75% showed low values at sites elGals, Boughaz I, elNaser, and Raba`a. The abiotic environmental effects in the Bardawil Lagoon are general to those generally observed in other areas influenced by organic wastes, namely, changed in the physic-chemical properties of the sediments and low oxygen concentrations in the bottom water due to decomposition of organic materials
Re-description of Lupocyclus philippinensis (Crustacea: Decapoda: Brachyura: Portunidae) Semper in Nauck, 1880 from the coastal waters of Karachi, Pakistan
Get PDFA specimen of the Lupocyclus philippinensis Semper in Nauck, 1880 commonly known as scissor swimming crab, was recently found in by catch of shrimp trawling and included as part of continuous taxonomic studies on crabs found in the coastal waters of Pakistan. The discovery is significant because it found after a long time. Redescription of L. philippinensis following the discovery of a female caught at Karachi fish harbor, Pakistan by Leene and Buitendijk (1952)
Características ambientales y algas nocivas en un área de producción de moluscos bivalvos del Canal Beagle, Argentina
Get PDFEn diciembre de 2013 se realizó un estudio para conocer las especies de microalgas tóxicas presentes en el área, las distintas toxinas que producen y los factores ambientales que condicionan la distribución de las comunidades de fitoplancton y su estructura. Se observó una alteración en la estructura de la comunidad fitoplantónica respecto al mismo período de años anteriores que indicó un retraso en las primeras etapas de la sucesión clásica. Dicho retraso influyó en el patrón anual de formación de floraciones de especies tóxicas en el canal y, en consecuencia, en los niveles de toxicidad de los bivalvos que normalmente se registran en esa época. El análisis de HPLC mostró escaso número de toxinas paralizantes de moluscos que coincidió con una muy baja concentración de células tóxicas. En las muestras analizadas se detectaron principalmente gonyautoxinas, sin presencia de toxina amnésica de moluscos. Los resultados aportan un conocimiento más detallado del perfil tóxico de los bivalvos de interés comercial en el área, que complementa el programa de monitoreo en curso. El análisis de los parámetros ambientales mostró que el sector interior de Bahía A. Brown es un área con circulación restringida que puede funcionar como reservorio potencial de los estadios bentónicos de resistencia de algunos dinoflagelados, proveyendo un inóculo inicial para la formación de floraciones o de eventos de toxicidad locales. La ausencia de floraciones de especies tóxicas y el bajo nivel de toxicidad de los moluscos del área en ese período se asociaron con las inusuales condiciones climáticas que se registraron en la región durante los meses previos, lo cual advierte sobre la necesidad de contar con un registro continuo de las variables meteorológicas para tratar de predecir la ocurrencia de floraciones de algas nocivas en el canal
In Memoriam: Daniel Raúl Hernández, Matemático
Get PDFDaniel Hernández ha fallecido y luego de su desaparición nuestra comunidad del INIDEP ya no será la misma. Hemos perdido a un querido colega y a una persona muy especial que supo cultivar vínculos de afecto y amistad no solo con aquellos que se acercaban a consultarlo o a iniciar eventualmente algún proyecto de trabajo en conjunto sino también con otros miembros del personal. Aunque de hábito retraído y ensimismado, quienes sabían acercarse a Daniel podían compartir su fino sentido del humor, una faceta que sin dudas era una delicia, y que afloraba pronto en la conversación aportando destellos de simpatía en las a veces prolongadas y no sencillas horas de trabajo conjunto
How the ASFA Partnership contributes to professional development
Get PDFIn this article, Daryl L. Superio explains how participation in ASFA has advanced his professional career and development. Daryl has participated in ASFA for over six years, during which time he has provided invaluable training and expertise to the Partnership
A Ranked Inventory of Commercially-important Mollusks of Panay, West Central Philippines as a Guide to Prioritize Research
Get PDFA first-ever effort to rank commercially-important mollusk species of Panay Island was conducted based on an extensive survey between March and April 2018. Ranking was based on the following criteria, namely: commercial value (40%), catch rates (20%), sources of threats (type of gear, processing plants, and number of fishers) (20%), frequency in the markets and source sites (10%), and literature available (10%), modified to a certain extent. A total of 90 mollusk species categorized into bivalves (49), gastropods (32), and cephalopods (9) were ranked. The comb pen shell Atrina pectinata (Pinnidae), Indian squid Uroteuthis duvaucelii (Loliginidae), and the scallop Mimachlamys sanguinea (formerly Chlamys senatoria) (Pectinidae) formed the top three species in the list strongly attributed to their high commercial value and thus catch rates. Squids, in general, are caught by trawls, whereas most of the other species are harvested primarily by gleaning and diving. The study highlights the high diversity of the malaco-fauna of Panay, as well as the multi-gear character of tropical fisheries. This ranked inventory can be used in prioritizing research on mollusks, by identifying target species for more in-depth studies useful for establishing their present status
Effect of Lactobacillus salivarius Dietary Supplementation on the Antioxidant Biomarkers of the Freshwater Shrimp Macrobrachium rosenbergii
Get PDFThe shrimp aquaculture is one of the most important livelihoods in the Philippines. Although there is an observed boost in the production of shrimps in the Philippines, there are remaining problems that are needed to be resolved. Bacterial and viral infections in shrimps have significantly affected its mortality, resulting in lower production and yield. In order to prevent or lessen this effect, various researches have been made to increase the resistance of shrimps against infections. In this study, a probiotic microorganism, Lactobacillus salivarius was used as a dietary supplementation for Macrobrachium rosenbergii and see its influence on the antioxidant biomarkers and temperature stress tolerance of the shrimp. Three concentrations of L. salivarius (1.0x107, 1.0x108, and 1.0x109 cells/g) were initially tested for its effect towards the oxidative stress tolerance and the oxygen consumption of the shrimp. The study involved the use of various antioxidant biomarkers including total glutathione (tGSH), catalase enzyme activity, and lipid peroxidation. Results showed that 1.0x108 cell/g of L. salivarius was the most effective concentration of probiotic microorganism per weight of feeds in improving the metabolic rate of the shrimp. Oxidative stress tolerance levels were observed to be increasing in terms of the catalase reaction (12.46 and 21.74 nmole/min) and lipid peroxidation (1.4X10-7 and 1.49X10-7 nmole MDA/mg protein) on both hepatopancreas and muscles tissues when the shrimp was fed with supplemented feeds. Also, high oxidant stress biomarkers were more evident on the hepatopancreas than the muscles
Yemaya, No.59, June 2019
Get PDFYemaya No. 59, dated June 2019, features articles from Fiji and India and an article on the 7th Global conference on gender in aquaculture and fisheries(GAF7), as well as an article on the recently-held roundtable in India on organising women by five groups engaged in organising women. The editorial comment calls for urgent need to look at levels of exclusion women are facing, despite the attention received at the international level. The article on Fiji shows the lack of sex disaggregated data available for any meaningful analysis. Nikita Gopal, in her article on GAF7, highlights the intersectionalities of power relations existing in the fisheries sector. The Roundtable highlighted the tremendous gains that women make when they collectively raise their voices in demand of their rights. The issue also celebrates the recent edition of Slow Fish held in Genoa, Italy. The Slow Fish Forum promotes small-scale fishing and responsible fish consumption and provides a unique space, particularly for women in the small-scale fisheries sector