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Prediction of suspended sediment distribution of Karoon river using artificial neural network
Get PDFAccurate estimation of sediment concentrations in hydraulic sediment transport from different viewpoint such as sediment discharge estimation of river, selection of hydraulic structures and etc. are important. With respect to importance of this issue in this study for prediction of sediment concentration of Karun river multi-layer perceptron artificial neural network (ANN / MLP) was used. For this purpose 125 field data including bottom concentration, flow velocity, nearest distance from the beach, and the total depth of flow and flow depth was used. Three statistical metrics namely mean absolute error (MAE), root mean square error (RMSE) and coefficient of determination (R^2) were used to evaluate the performance of ANN model. The result shows that MLP model with one hidden layer, Sigmoid transfer function and 5 neurons have best structure in the modeling of sediment concentration of Kroon River. The R^2 and RMSE value is equal to 0.953 and 63.37 mg/l in training stage and 0.752 and 203.02 mg/l in testing stage, respectively. Finally, the sensitive analysis also showed that the nearest distance from the beach and flow depth had the most and the least effect on the sediment concentration, respectively
Antioxidant and antibacterial assay of two red marine macro-algae of Bandar Abbas coastal
Get PDFSeaweed is favored seafood in some regions and is also used as feedstock for extracting fine chemicals. The total global seaweed production continues to grow This study investigated the biological activities of n-Hexane, Ethylacetate and Methanol extract of two red marine macro algae (Gracilariopsis persica and Hypnea flagelliformis), collected from the coast of Bandar Abbas, Persian Gulf, Iran. For identification the superior species with biological properties, the tested activities included Carotenoids content; total Phenolic content, total flavonoids content, antioxidant activity at the concentration (3 mg/ml) by ferric reducing power (FRP) and total antioxidant capacity (TAC) assay and at final, antibacterial activity was evaluated. This study revealed that the more effective macro algae extracts by maximum antioxidant capacity: FRP and TAC, were recorded for Ethylacetate extracts. The result showed the highest content of phenolic and flavonoid compounds were recorded for the Methanol extracts of Gp. persica, 45.12±0.01 (mg GA/gr DW.) and 2.28±0.007 (mg QE /gr DW.), respectively while H. flagelliformis showed the maximum Carotenoid content 17±0.06 (mg 100g^-1). In addition, the highest antibacterial activity was recorded for the n-hexane and followed by Ethylacetate extracts. In general comparison, though, according to the results, antioxidant and antibacterial activity of species in this study were calculated less than standard, but could be accounted these seaweeds as safe biological properties and with abundance of them in coastal of Bandar Abbas, could be considered for future applications in medicine and dietary supplements
Determination of lethal range and median lethal concentration (LC50 96h) values of diazinon on Caspian Sea common bream (Abramis brama)
Get PDFPesticides are environmental contaminants which normally enter to aquatic ecosystems after being used in aquaculture. In this research, acute toxicity of diazinon was studied on Caspian Sea common bream (Abramis brama). This pesticide may enter in aquatic food chain and cause serious problems for aquatic organisms as well as human. The acute toxicity test was performed during 96h in static renewal system based on the standard method proposed by OECD. A range finding test was carried out in aquariums containing 10L of test solution to determine the lethal range of diazinon on fish. The acute toxicity test was then preformed in 5 treatments and 3 triplicates for each treatment. Obtained data were analyzed using probit analysis with %5 confidence limit. According to the results, LC_50 24h, LC_50 48h, LC_50 72h and LC_50 96h of diazinon on Caspian Sea common bream was 10.974, 10.391, 9.134 and 7.316 respectively. The maximum acceptable toxicant concentration (MATC) of diazinon on Caspian Sea common bream was 0.073 mg/l and the lowest observed effect concentration which is equal to LC_50 96h was 2.63 mg/l. According to the results and comparing with other studies, it can be discussed that Caspian Sea common bream is more resistant against diazinon rather than other fish species. In addition, lethal toxicity of diazinon takes place in a moderate range of toxicant concentrations
SSF-RPOA: deep-rooted problems, great expectations
Get PDFCan the Ministerial declaration and regional plan of action signed recently in Malta turn the tide of fortune for small-scale fisheries in the Mediterranean and Black Sea?. On 26 September in Malta, 18 Mediterranean and Black Sea coastal states committed themselves to developing “objectives, principles and concrete actions” to be applied across the region through a regional plan of action (RPOA) and thus “to ensure the long-term environmental, economic and social sustainability of small-scale fisheries”
Cambodia - fishery rights: from individual rights to community commons
Get PDFCambodia’s community fisheries initiative is the most extensive and well-developed system of community fisheries in the world. The current fishery rights system in Cambodia is the most extensive and well-developed system of community fisheries in the world”, said the European Union (EU) Representative to Cambodia at the FAO/UN User Rights 2015 Conference held in Siem Reap, Cambodia. Defining tenurial boundaries and proving rights in an aquatic milieu is a daunting task. This is further confounded when dealing with a dynamic land-water interface marked by significant seasonal fluctuations
Indonesia: hooray for manta rays
Get PDFLamakera, a tiny village in Indonesia, is a centre for the global trade in manta rays, which are listed as vulnerable by the International Union for Conservation of Nature (IUCN
MCS (monitoring, control and surveillance): fishing for the future
Get PDFA World Bank-funded project for 12 countries in the East African and Indian Ocean regions attempts to allow fishers to maximize revenue but not deplete stocks. This interview took place on the sidelines of the Second Regional Workshop on Monitoring, Control and Surveillance, organized by the Bay of Bengal Programme, Inter- Governmental Organisation in Chennai during 3 - 4 October 2018
Give a woman a fish
Get PDFA review of the documentary film about women fishers living in the floating villages of Tonle Sap Lake, Cambodia, considered the world’s most productive inland fishery. Produced by Conservation International and Fintrac; filmed and edited by Dominique Tardy, scripted by Olivier Joffre and narrated by Susan Novak. Duration 12 min 29 sec; Language: English
Feeding strategy analysis of blue swimming crab (Portunus pelagicus, Linnaeus, 1758) using Castello's graphical model in Khuzestan coastal water
Get PDFFeeding strategy of blue swimming crab (Portunus pelagicus) was investigated monthly in Khuzestan province water from April-2016 to march-2017. Samples were catch by trawl net. The content of P. pelagicus stomachs, percentage of occurrence frequency and Frequency percentage of feeding items was checked. In crab stomachs different feeding items group such as crustacean, mollusks, sponges, phytoplanktons, corals, fish, sand particles and etc. Was observed. The highest frequency of occurrence belonging to sponges, crustaceans and mollusks, respectively. Furthermore, Frequency percentage of sponges (38.65%) was higher than other preys. Costello's graphical model analysis Results analysis of P. pelagicus stomach content by Costello's model showed that this crab is a predator with specific feeding nich and feeding specific prey include sponges, crustacean and mollusks during a year. Though, it's feeding pattern show few seasonally fluctuations. In this model, phytoplanktons, fish, polycheats, corals, nematode, protista, ctenophore, nematodes, cestod, sea insects and sand identified as accidental or rare prey. Probably, ingest by crab while feeding from specific prey
Profile: Fish, ponds and empowered lives
Get PDFUnder Suman Singh’s leadership, women in Madhubani, India, gain greater control over their lives