Search results for: marine fish
1133 The Spatial Classification of China near Sea for Marine Biodiversity Conservation Based on Bio-Geographical Factors
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Global biodiversity continues to decline as a result of global climate change and various human activities, such as habitat destruction, pollution, introduction of alien species and overfishing. Although there are connections between global marine organisms more or less, it is better to have clear geographical boundaries in order to facilitate the assessment and management of different biogeographical zones. And so area based management tools (ABMT) are considered as the most effective means for the conservation and sustainable use of marine biodiversity. On a large scale, the geographical gap (or barrier) is the main factor to influence the connectivity, diffusion, ecological and evolutionary process of marine organisms, which results in different distribution patterns. On a small scale, these factors include geographical location, geology, and geomorphology, water depth, current, temperature, salinity, etc. Therefore, the analysis on geographic and environmental factors is of great significance in the study of biodiversity characteristics. This paper summarizes the marine spatial classification and ABMTs used in coastal area, open oceans and deep sea. And analysis principles and methods of marine spatial classification based on biogeographic related factors, and take China Near Sea (CNS) area as case study, and select key biogeographic related factors, carry out marine spatial classification at biological region scale, ecological regionals scale and biogeographical scale. The research shows that CNS is divided into 5 biological regions by climate and geographical differences, the Yellow Sea, the Bohai Sea, the East China Sea, the Taiwan Straits, and the South China Sea. And the bioregions are then divided into 12 ecological regions according to the typical ecological and administrative factors, and finally the eco-regions are divided into 98 biogeographical units according to the benthic substrate types, depth, coastal types, water temperature, and salinity, given the integrity of biological and ecological process, the area of the biogeographical units is not less than 1,000 km². This research is of great use to the coastal management and biodiversity conservation for local and central government, and provide important scientific support for future spatial planning and management of coastal waters and sustainable use of marine biodiversity.Keywords: spatial classification, marine biodiversity, bio-geographical, conservation
Procedia PDF Downloads 1461132 Establishment of Farmed Fish Welfare Biomarkers Using an Omics Approach
Authors: Pedro M. Rodrigues, Claudia Raposo, Denise Schrama, Marco Cerqueira
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Farmed fish welfare is a very recent concept, widely discussed among the scientific community. Consumers’ interest regarding farmed animal welfare standards has significantly increased in the last years posing a huge challenge to producers in order to maintain an equilibrium between good welfare principles and productivity, while simultaneously achieve public acceptance. The major bottleneck of standard aquaculture is to impair considerably fish welfare throughout the production cycle and with this, the quality of fish protein. Welfare assessment in farmed fish is undertaken through the evaluation of fish stress responses. Primary and secondary stress responses include release of cortisol and glucose and lactate to the blood stream, respectively, which are currently the most commonly used indicators of stress exposure. However, the reliability of these indicators is highly dubious, due to a high variability of fish responses to an acute stress and the adaptation of the animal to a repetitive chronic stress. Our objective is to use comparative proteomics to identify and validate a fingerprint of proteins that can present an more reliable alternative to the already established welfare indicators. In this way, the culture conditions will improve and there will be a higher perception of mechanisms and metabolic pathway involved in the produced organism’s welfare. Due to its high economical importance in Portuguese aquaculture Gilthead seabream will be the elected species for this study. Protein extracts from Gilthead Seabream fish muscle, liver and plasma, reared for a 3 month period under optimized culture conditions (control) and induced stress conditions (Handling, high densities, and Hipoxia) are collected and used to identify a putative fish welfare protein markers fingerprint using a proteomics approach. Three tanks per condition and 3 biological replicates per tank are used for each analisys. Briefly, proteins from target tissue/fluid are extracted using standard established protocols. Protein extracts are then separated using 2D-DIGE (Difference gel electrophoresis). Proteins differentially expressed between control and induced stress conditions will be identified by mass spectrometry (LC-Ms/Ms) using NCBInr (taxonomic level - Actinopterygii) databank and Mascot search engine. The statistical analysis is performed using the R software environment, having used a one-tailed Mann-Whitney U-test (p < 0.05) to assess which proteins were differentially expressed in a statistically significant way. Validation of these proteins will be done by comparison of the RT-qPCR (Quantitative reverse transcription polymerase chain reaction) expressed genes pattern with the proteomic profile. Cortisol, glucose, and lactate are also measured in order to confirm or refute the reliability of these indicators. The identified liver proteins under handling and high densities induced stress conditions are responsible and involved in several metabolic pathways like primary metabolism (i.e. glycolysis, gluconeogenesis), ammonia metabolism, cytoskeleton proteins, signalizing proteins, lipid transport. Validition of these proteins as well as identical analysis in muscle and plasma are underway. Proteomics is a promising high-throughput technique that can be successfully applied to identify putative welfare protein biomarkers in farmed fish.Keywords: aquaculture, fish welfare, proteomics, welfare biomarkers
Procedia PDF Downloads 1451131 Neighbor Caring Environment System (NCE) Using Parallel Replication Mechanism
Authors: Ahmad Shukri Mohd Noor, Emma Ahmad Sirajudin, Rabiei Mamat
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Pertaining to a particular Marine interest, the process of data sampling could take years before a study can be concluded. Therefore, the need for a robust backup system for the data is invariably implicit. In recent advancement of Marine applications, more functionalities and tools are integrated to assist the work of the researchers. It is anticipated that this modality will continue as research scope widens and intensifies and at the same to follow suit with current technologies and lifestyles. The convenience to collect and share information these days also applies to the work in Marine research. Therefore, Marine system designers should be aware that high availability is a necessary attribute in Marine repository applications as well as a robust backup system for the data. In this paper, the approach to high availability is related both to hardware and software but the focus is more on software. We consider a NABTIC repository system that is primitively built on a single server and does not have replicated components. First, the system is decomposed into separate modules. The modules are placed on multiple servers to create a distributed system. Redundancy is added by placing the copies of the modules on different servers using Neighbor Caring Environment System(NCES) technique. NCER is utilizing parallel replication components mechanism. A background monitoring is established to check servers’ heartbeats to confirm their aliveness. At the same time, a critical adaptive threshold is maintained to make sure a failure is timely detected using Adaptive Fault Detection (AFD). A confirmed failure will set the recovery mode where a selection process will be done before a fail-over server is instructed. In effect, the Marine repository service is continued as the fail-over masks a recent failure. The performance of the new prototype is tested and is confirmed to be more highly available. Furthermore, the downtime is not noticeable as service is immediately restored automatically. The Marine repository system is said to have achieved fault tolerance.Keywords: availability, fault detection, replication, fault tolerance, marine application
Procedia PDF Downloads 3131130 Application and Limitation of Heavy Metal Pollution Indicators in Coastal Environment of Pakistan
Authors: Noor Us Saher
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Oceans and Marine areas have a great importance, mainly regarding food resources, fishery products and reliance of livelihood. Aquatic pollution is common due to the incorporation of various chemicals mainly entering from urbanization, industrial and commercial facilities, such as oil and chemical spills. Many hazardous wastes and industrial effluents contaminate the nearby areas and initiate to affect the marine environment. These contaminated conditions may become worse in those aquatic environments situated besides the world’s largest cities, which are hubs of various commercial activities. Heavy metal contamination is one of the most important predicaments for marine environments and during past decades this problem has intensified due to an increase in urbanization and industrialization. Coastal regions of Pakistan are facing severe threats from various organic and inorganic pollutants, especially the estuarine and coastal areas of Karachi city, the most populated and industrialized city situated along the coastline. Metal contamination causes severe toxicity in biota resulting the degradation of Marine environments and depletion of fishery resources and sustainability. There are several abiotic (air, water and sediment) and biotic (fauna and flora) indicators that indicate metal contamination. However, all these indicators have certain limitations and complexities, which delay their implementation for rehabilitation and conservation in the marine environment. The inadequate evidences have presented on this significant topic till the time and this study discussed metal pollution and its consequences along the marine environment of Pakistan. This study further helps in identification of possible hazards for the ecological system and allied resources for management strategies and decision making for sustainable approaches.Keywords: coastal and estuarine environment, heavy metals pollution, pollution indicators, Pakistan
Procedia PDF Downloads 2391129 Exposure of Pacu, Piaractus mesopotamicus Gill Tissue to a High Stocking Density: An Ion Regulatory and Microscopy Study
Authors: Wiolene Montanari Nordi, Debora Botequio Moretti, Mariana Caroline Pontin, Jessica Pampolini, Raul Machado-Neto
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Gills are organs responsible for respiration and osmoregulation between the fish internal environment and water. Under stress conditions, oxidative response and gill plasticity to attempt to increase gas exchange area are noteworthy, compromising the physiological processes and therefore fish health. Colostrum is a dietary source of nutrients, immunoglobulin, antioxidant and bioactive molecules, essential for immunological protection and development of the gastrointestinal epithelium. The hypothesis of this work is that antioxidant factors present in the colostrum, unprecedentedly tested in gills, can minimize or reduce the alteration of its epithelium structure of juvenile pacu (Piaractus mesopotamicus) subjected to high stocking density. The histological changes in the gills architecture were characterized by the frequency, incidence and severity of the tissue alteration and ionic status. Juvenile (50 kg fish/m3) were fed with pelleted diets containing 0, 10, 20 or 30% of lyophilized bovine colostrum (LBC) inclusion and at 30 experimental days, gill and blood samples were collected in eight fish per treatment. The study revealed differences in the type, frequency and severity (histological alterations index – HAI) of tissue alterations among the treatments, however, no distinct differences in the incidence of alteration (mean alteration value – MAV) were observed. The main histological changes in gill were elevation of the lamellar epithelium, excessive cell proliferation of the filament and lamellar epithelium causing total or partial melting of the lamella, hyperplasia and hypertrophy of lamellar and filament epithelium, uncontrolled thickening of filament and lamellar tissues, mucous and chloride cells presence in the lamella, aneurysms, vascular congestion and presence of parasites. The MAV obtained per treatment were 2.0, 2.5, 1.8 and 2.5 to fish fed diets containing 0, 10, 20 and 30% of LBC inclusion, respectively, classifying the incidence of gill alterations as slightly to moderate. The severity of alteration of individual fish of treatment 0, 10 and 20% LBC ranged values from 5 to 40 (HAI average of 20.1, 17.5 and 17.6, respectively, P > 0.05), and differs from 30% LBC, that ranged from 6 to 129 (HAI mean of 77.2, P < 0.05). The HAI value in the treatments 0, 10 and 20% LBC reveals gill tissue with injuries classified from slightly to moderate, while in 30% LBC moderate to severe, consequence of the onset of necrosis in the tissue of two fish that compromises the normal functioning of the organ. In relation to frequency of gill alterations, evaluated according to absence of alterations (0) to highly frequent (+++), histological alterations were observed in all evaluated fish, with a trend of higher frequency in 0% LBC. The concentration of Na+, Cl-, K+ and Ca2+ did not changed in all treatments (P > 0.05), indicating similar capacity of ion exchange. The concentrations of bovine colostrum used in diets of present study did not impair the alterations observed in the gills of juvenile pacu.Keywords: histological alterations of gill tissue, ionic status, lyophilized bovine colostrum, optical microscopy
Procedia PDF Downloads 2931128 Reproductive Behavior of the Red Sea Immigrant Lagocephalus sceleratus (Gmelin, 1789) from the Mediterranean Coast, Egypt
Authors: Mahmoud M. S. Farrag, Alaa A. K. Elhaweet, El-Sayed Kh. A. Akel, Mohsen A. Moustafa
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The present work aimed to study the reproductive strategy of the common lessepsian puffer fish Lagocephalus sceleratus (Gmelin, 1879) from the Egyptian Mediterranean Waters. It is a famous migratory species plays an important role in the field of fisheries and ecology of aquatic ecosystem. The specimens were collected monthly from the landing centers along the Egyptian Mediterranean coast during 2012. Six maturity stages were recorded: (I) Thread like stage, (II) Immature stage (Virgin stage), (III) Maturing stage (Developing Virgin and recovering spent), (IV) Nearly ripe stage, (V) Fully ripe, (VI) Spawning stage, (VII) Spent stage. According to sex ratio, males exhibited higher number than females representing 52.44 % of the total fishes with sex ratio 1: 0.91. Fish length corresponding to 50% maturation was 38.5 cm for males and 41 cm for females. The corresponding ages (age at first maturity) are equal to 2.14 and 2.27 years for male and female respectively. The ova diameter ranged from 0.02mm to 0.85mm, the mature ova ranged from 0.16mm to 0.85mm and showed progressive increase from April towards September. Also, the presences of ova diameter in one peak of mature and ripe eggs in the ovaries were observed during spawning period. The relationship between gutted weight and absolute fecundity indicated that that fecundity increased as the fish grew in weight. The absolute fecundity ranged from 260288 to 2372931 for fish weight ranged from 698 to 3285 cm with an average of 1449522±720975. The relative fecundity ranged from 373 to 722 for fish weight ranged from 698 to 3285 cm with an average of 776±231. The spawning season of L. sceleratus was investigated from the data of gonado-somatic index and monthly distribution of maturity stages along the year as well as sequence of ova diameter for mature stages and exhibited a relatively prolong spawning season extending from April for both sexes and ends in August for male while ends in September for female. Fish releases its ripe ova in one batch during the spawning season. Histologically, the ovarian cycle of L. sceleratus was classified into six stages and the testicular cycle into five stages. Histological characters of gonads of L. sceleratus during the year of study had confirmed the previous results of distribution of maturity stages, gonado-somatic index and ova diameter, indicating this fish species has prolonged spawning season from April to September. This species is considered totally or uni spawner with synchronous group as it contained one to two developmental stages at the same gonad.Keywords: Lagocephalus sceleratus, reproductive biology, oogenesis, histology
Procedia PDF Downloads 2961127 Food and Feeding Habit of Clarias anguillaris in Tagwai Reservoir, Minna, Niger State, Nigeria
Authors: B. U. Ibrahim, A. Okafor
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Sixty-two (62) samples of Clarias anguillaris were collected from Tagwai Reservoir and used for the study. 29 male and 33 female samples were obtained for the study. Body measurement indicated that different sizes were collected for the study. Males, females and combined sexes had standard length and total length means of 26.56±4.99 and 31.13±6.43, 27.17±5.21 and 30.62±5.43, 26.88±5.08 and 30.86±5.88 cm, respectively. The weights of males, females and combined sexes have mean weights of 241.10±96.27, 225.75±78.66 and 232.93±86.95 gm, respectively. Eight items; fish, insects, plant materials, sand grains, crustaceans, algae, detritus and unidentified items were eaten as food by Clarias anguilarias in Tagwai Reservoir. Frequency of occurrence and numerical methods used in stomach contents analysis indicated that fish was the highest, followed by insect, while the lowest was the algae. Frequency of stomach fullness of Clarias anguillaris showed low percentage of empty stomachs or stomachs without food (21.00%) and high percentage of stomachs with food (79.00%), which showed high abundance of food and high feeding intensity during the period of study. Classification of fish based on feeding habits showed that Clarias anguillaris in this study is an omnivore because it consumed both plant and animal materials.Keywords: stomach content, feeding habit, Clarias anguillaris, Tagwai Reservoir
Procedia PDF Downloads 5851126 Aspects of the Reproductive Biology of Brook Trout Neolissochilus stracheyi (Day, 1871) in Northern, Thailand
Authors: Thapanee Pholdee, Apinun Suvarnaraksha
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Reproductive biology of Brook trout, Neolissochilus stracheyi (Day, 1871), were sampled in the Northern of Thailand during October 2010 - September 2011 from the fisherman, using gillnet of various mesh sizes. For the study of relationships between total length and body weight, spawning seasons, sex ratio and fecundity. At least 66 fish samples were used every month. The result showed that the total 821 Brook trout had 7.4-61(23.32±5.91 cm). There were 353 males that had fish samples there were 8.5-45.1 cm of TL (22.36±5.91cm) and 468 females that had 7.4±61 cm of TL (24.04±7.09 cm). The relationships equation between total length and weight was W = 0.008TL³.⁰⁶⁴ (r² = 0.940) for total fish, W=0.007TL³.¹⁰⁷ (r² = 0.946) for females and W=0.010TL³.⁰⁰³ (r² = 0.930) for males. The relative condition factor (K) of male and female was 1.090±0.067 and 1.116±0.102 respectively. The max of GSI was in June for male and female. The spawning season was found all year round with three peaks: January, June, and August. Estimated fecundity of mature ovaries ranged from 220 to 3,500 eggs. The estimated average fecundity was 1404.55 ±651.51 eggs. The relationships between fecundity and total length revealed F= 121.1TL-2100 and relationships between fecundity and weight revealed F= 4.535 + 128.78. The results from studies can be further applied to the economic culture, conservation, and management of the Brook trout in Northern, Thailand.Keywords: reproductive biology, Neolissochilus stracheyi, Northern Thailand, Brook trout
Procedia PDF Downloads 3001125 Towards Automated Remanufacturing of Marine and Offshore Engineering Components
Authors: Aprilia, Wei Liang Keith Nguyen, Shu Beng Tor, Gerald Gim Lee Seet, Chee Kai Chua
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Automated remanufacturing process is of great interest in today’s marine and offshore industry. Most of the current remanufacturing processes are carried out manually and hence they are error prone, labour-intensive and costly. In this paper, a conceptual framework for automated remanufacturing is presented. This framework involves the integration of 3D non-contact digitization, adaptive surface reconstruction, additive manufacturing and machining operation. Each operation is operated and interconnected automatically as one system. The feasibility of adaptive surface reconstruction on marine and offshore engineering components is also discussed. Several engineering components were evaluated and the results showed that this proposed system is feasible. Conclusions are drawn and further research work is discussed.Keywords: adaptive surface reconstruction, automated remanufacturing, automatic repair, reverse engineering
Procedia PDF Downloads 3191124 The Fishery and Electricity Symbiosis Environment and Social Inspection in Taiwan: The Kaohsiung City Example
Authors: Bing-Shun Huang, Hung-Ju Chiu, Wen-Kai Hsieh, Hsiu-Chuan Lin, Ming-Lung Hung
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Taiwan's solar photovoltaic target in 2025 is 20 GW, of which the fish-electricity symbiosis target is 4 GW. In the future, many solar photovoltaic installations may cause local environmental or social impacts. Therefore, the Taiwan government inspects the fish-electricity symbiosis to reduce the impact of solar photovoltaics on the local environment or society. This stuy takes the symbiosis of fishery and electricity in Kaohsiung City as an example to explore Taiwan's environmental and social inspection practices. It mainly analyzes the two aspects of environmental ecology and social economy. The results show that the environmental inspection is mainly through site surveys, ecological information mapping, on-site interviews, and public consultation meetings. Social inspection mainly includes document analysis, on-site interviews, site surveys, expert discussions, and public consultations to identify possible local problems. Although the government had recognized the local issues, the future status may also change. It is recommended that future photoelectric companies should reconfirm the current situation of development sites when applying for the installation and propose countermeasures to solve the problem.Keywords: taiwan, fish-electricity symbiosis, environment, society, inspection
Procedia PDF Downloads 1911123 Treatment of Dredged Marine Sediments for Their Reuse in Road Construction
Authors: F. Ben Abdelghani, W. Maherezi
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Dredging operations generate, each year, a great quantity of marine sediments. These raw materials can not be used in road construction without a specific treatment process. Sediments suitability tests has shown that most of studied sediments are not suitable to be used in road construction. In order to improve their compacity and their mechanical performance, addition of a granular material is recommended. The use of a dredged sand, to improve the granular mixture containing sediments, allows a better management of the two types of dredge materials (sand and sediment). In this study, a new road material containing dredged marine sediments and dredged sand is formulated and treated by adding various binders. Mechanical performance investigation of different mixtures by measuring Proctor-IPI values and simple compressive strengths is realized.Keywords: dredged sediments, suitability tests, road construction, hydraulic binder, mechanical performance
Procedia PDF Downloads 3571122 Invasive Asian Carp Fish Species: A Natural and Sustainable Source of Methionine for Organic Poultry Production
Authors: Komala Arsi, Ann M. Donoghue, Dan J. Donoghue
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Methionine is an essential dietary amino acid necessary to promote growth and health of poultry. Synthetic methionine is commonly used as a supplement in conventional poultry diets and is temporarily allowed in organic poultry feed for lack of natural and organically approved sources of methionine. It has been a challenge to find a natural, sustainable and cost-effective source for methionine which reiterates the pressing need to explore potential alternatives of methionine for organic poultry production. Fish have high concentrations of methionine, but wild-caught fish are expensive and adversely impact wild fish populations. Asian carp (AC) is an invasive species and its utilization has the potential to be used as a natural methionine source. However, to our best knowledge, there is no proven technology to utilize this fish as a methionine source. In this study, we co-extruded Asian carp and soybean meal to form a dry-extruded, methionine-rich AC meal. In order to formulate rations with the novel extruded carp meal, the product was tested on cecectomized roosters for its amino acid digestibility and total metabolizable energy (TMEn). Excreta was collected and the gross energy, protein content of the feces was determined to calculate Total Metabolizable Energy (TME). The methionine content, digestibility and TME values were greater for the extruded AC meal than control diets. Carp meal was subsequently tested as a methionine source in feeds formulated for broilers, and production performance (body weight gain and feed conversion ratio) was assessed in comparison with broilers fed standard commercial diets supplemented with synthetic methionine. In this study, broiler chickens were fed either a control diet with synthetic methionine or a treatment diet with extruded AC meal (8 replicates/treatment; n=30 birds/replicate) from day 1 to 42 days of age. At the end of the trial, data for body weights, feed intake and feed conversion ratio (FCR) was analyzed using one-way ANOVA with Fisher LSD test for multiple comparisons. Results revealed that birds on AC diet had body weight gains and feed intake comparable to diets containing synthetic methionine (P > 0.05). Results from the study suggest that invasive AC-derived fish meal could potentially be an effective and inexpensive source of sustainable natural methionine for organic poultry farmers.Keywords: Asian carp, methionine, organic, poultry
Procedia PDF Downloads 1481121 Utilization and Proximate Composition of Nile Tilapia, Common Carp and African Mudfish Polycultured in Fertilized Ponds
Authors: I. A. Yola
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Impact of poultry dropping, cow dung and rumen content on utilization and proximate composition of Oreochromis niliticus, Clarias gariepinus and Cyprinus capio in a polyculture system were studied. The research was conducted over a period of 52 weeks. Poultry droppings (PD), cow dung (CD) and rumen content (RC) were applied at three levels 30g,60g and 120g/m2/week, 25g,50g and 100g/m2/week and 22g, 44g and 88g/m2/week treatment, respectively. The control only conventional feed with 40% CP without manure application was used. Physicochemical and biological properties measured were higher in manure pond than control. The difference was statistically significant (P < 0.05) between and within treatments with exception of temperature with a combined mean of 27.900C. The water was consistently alkaline with mean values for pH of 6.61, transparency 22.6cm, conductivity 35.00µhos/cm, dissolved oxygen 4.6 mg/l, biological oxygen demand 2.8mg/l, nitrate and phosphates 0.9mg/l and 0.35mg/l, respectively. The three fish species increase in weight with increased manure rate, with a higher value in PD treatment on C. capio record 340g, O. niloticus weighed 310g and C. gariepinus 280g over the experimental period. Fishes fed supplementary diet (control) grew bigger with highest value on C. capio (685g) O. niloticus (620g) and then C. gariepinus (526g). The differences were statistically significant (P < 0.05). The result of whole body proximate analysis indicated that various manures and rates had an irregular pattern on the protein and ash gain per 100g of fish body weight gain. The combined means for whole fish carcass protein, lipids, moisture, ash and gross energy were 11.84, 2.43, 74.63, 3.00 and 109.9 respectively. The notable exceptions were significant (p < 0.05) increases in body fat and gross energy gains in all fish species accompanied by decreases in percentages of moisture as manure rates increased. Survival percentage decreases from 80% to 70%. It is recommended to use poultry dropping as manure/feeds at the rate of 120kg/ha/week for good performances in polyculture.Keywords: organic manure, Nile tilapia, African mud fish, common carp, proximate composition
Procedia PDF Downloads 5451120 Blue Economy and Marine Mining
Authors: Fani Sakellariadou
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The Blue Economy includes all marine-based and marine-related activities. They correspond to established, emerging as well as unborn ocean-based industries. Seabed mining is an emerging marine-based activity; its operations depend particularly on cutting-edge science and technology. The 21st century will face a crisis in resources as a consequence of the world’s population growth and the rising standard of living. The natural capital stored in the global ocean is decisive for it to provide a wide range of sustainable ecosystem services. Seabed mineral deposits were identified as having a high potential for critical elements and base metals. They have a crucial role in the fast evolution of green technologies. The major categories of marine mineral deposits are deep-sea deposits, including cobalt-rich ferromanganese crusts, polymetallic nodules, phosphorites, and deep-sea muds, as well as shallow-water deposits including marine placers. Seabed mining operations may take place within continental shelf areas of nation-states. In international waters, the International Seabed Authority (ISA) has entered into 15-year contracts for deep-seabed exploration with 21 contractors. These contracts are for polymetallic nodules (18 contracts), polymetallic sulfides (7 contracts), and cobalt-rich ferromanganese crusts (5 contracts). Exploration areas are located in the Clarion-Clipperton Zone, the Indian Ocean, the Mid Atlantic Ridge, the South Atlantic Ocean, and the Pacific Ocean. Potential environmental impacts of deep-sea mining include habitat alteration, sediment disturbance, plume discharge, toxic compounds release, light and noise generation, and air emissions. They could cause burial and smothering of benthic species, health problems for marine species, biodiversity loss, reduced photosynthetic mechanism, behavior change and masking acoustic communication for mammals and fish, heavy metals bioaccumulation up the food web, decrease of the content of dissolved oxygen, and climate change. An important concern related to deep-sea mining is our knowledge gap regarding deep-sea bio-communities. The ecological consequences that will be caused in the remote, unique, fragile, and little-understood deep-sea ecosystems and inhabitants are still largely unknown. The blue economy conceptualizes oceans as developing spaces supplying socio-economic benefits for current and future generations but also protecting, supporting, and restoring biodiversity and ecological productivity. In that sense, people should apply holistic management and make an assessment of marine mining impacts on ecosystem services, including the categories of provisioning, regulating, supporting, and cultural services. The variety in environmental parameters, the range in sea depth, the diversity in the characteristics of marine species, and the possible proximity to other existing maritime industries cause a span of marine mining impact the ability of ecosystems to support people and nature. In conclusion, the use of the untapped potential of the global ocean demands a liable and sustainable attitude. Moreover, there is a need to change our lifestyle and move beyond the philosophy of single-use. Living in a throw-away society based on a linear approach to resource consumption, humans are putting too much pressure on the natural environment. Applying modern, sustainable and eco-friendly approaches according to the principle of circular economy, a substantial amount of natural resource savings will be achieved. Acknowledgement: This work is part of the MAREE project, financially supported by the Division VI of IUPAC. This work has been partly supported by the University of Piraeus Research Center.Keywords: blue economy, deep-sea mining, ecosystem services, environmental impacts
Procedia PDF Downloads 721119 Copper Sulphate Effect on Cyprinus Carpio Common Fish Parasites
Authors: Jawdhari Abdulhusein, Dan Mihăilescu, Cristian-Emilian Pop, Nicolai Crăciun
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Cyprinus Carpio adult specimens were captured from a single spot location from the Danube River and transported to the Laboratory of Faculty of Biology, University of Bucharest. The specimens were measured, weighed and randomly divided in five groups for later Copper Sulphate (CuSO4) exposure, as well as one control group. From the control group, 3 specimens were immediately sacrificed and microscopically inspected for parasite’s presence in the gills. During the histological inspection of the control group specimens, Ichthyophthiriusmultifiliis, Gyrodactylu ssp., MyxobolusOviforis, and Trichodinacottidarumwere abundantly identified in the gills. The exposure to a single dose of CuSO4 per group took place for 7 days under controlled conditions: water alkalinity ≈ 100 mg/L, temperature 23–24 °C, oxygenation 7.40–7.80 mg/L, and pH 6.10–6.40, the parameters were monitored on an hourly basis and adjusted when needed. After the exposure, all specimens were sacrificed, and the gill tissues were inspected. It was found that concentrations of 0.10, 0.25 and 0.30 ppm of CuSO4 did not affect the presence of parasites, as for 0.40 ppm of CuSO4 it significantly affected onlyIchthyophthiriusmultifiliisandMyxobolusOviforis, while concentration 0.50 ppm of CuSO4 (≈0.20 ppm of Cu2+) eliminated all 4 parasites species previously present in the fish gills, also, there were some histopathological changes to the gills tissue. These findings suggest that low concentrations of CuSO4 treatment for fish parasites are a safe and economical option if used correctly for a brief length of time.Keywords: copper sulphate, cyprinus carpio, parasites, danube river
Procedia PDF Downloads 1321118 A Comparative Study on Primary Productivity in Fish Cage Culture Unit and Fish Pond in Relation to Different Level of Water Depth
Authors: Pawan Kumar Sharma, J. Stephan Sampath Kumar, D. Manikandavelu, V. Senthil Kumar
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The total amount of productivity in the system is the gross primary productivity. The present study was carried out to understand the relationship between productivity in the cages and water depth. The experiment was conducted in the fish cages installed in the pond at the Directorate of Sustainable Aquaculture, Thanjavur, Tamil Nadu Dr. J. Jayalalithaa Fisheries University, Tamil Nadu (10° 47' 13.1964'' N; 79° 8' 16.1700''E). Primary productivity was estimated by light and dark bottle method. The measurement of primary productivity was done at different depths viz., 20 cm, 40 cm, and 60 cm. Six Biological Oxygen Demand bottles of 300 ml capacity were collected and tagged. The productivity was obtained in mg O2/l/hr. The maximum dissolved oxygen level at 20 cm depth was observed 5.62 ± 0.22 mg/l/hr in the light bottle in pond water while the minimum dissolved oxygen level at 20 cm depth in a cage was observed 3.62 ± 0.18 mg/l/hr in dark bottle. In the same way, the maximum and minimum value of dissolved oxygen was observed at 40, and 60 cm depth and results were compared. A slight change in pH was observed in the cage and pond. The maximum gross primary productivity observed was 1.97 mg/l/hr in pond at 20 cm depth while minimum gross primary productivity observed was 0.82±0.16 mg/l/hr in a cage at 60 cm depth. The community respiration was also variable with the depth in both cage and pond. Maximum community respiration was found 1.50±0.19 mg/l/hr in pond at 20 cm depth. A strong positive linear relationship was observed between primary productivity and fish yields in ponds. The pond primary productivity can contribute substantially to the nutrition of farm-raised aquaculture species, including shrimp. The growth of phytoplankton’s is dependent on the sun light, availability of primary nutrients (N, P, and K) in the water body and transparency, so to increase the primary productivity fertilization through organic manure may be done that will clean to the pond environment also.Keywords: cage aquaculture, water depth, net primary productivity, gross primary productivity, community respiration
Procedia PDF Downloads 1971117 Investigating Trophic Relationships in Moroccan Marine Ecosystems: A Study of the Mediterranean and Atlantic Using Ecopath
Authors: Salma Aboussalam, Karima Khalil, Khalid Elkalay
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An Ecopath model was employed to investigate the trophic structure, function, and current state of the Moroccan Mediterranean Sea ecosystem. The model incorporated 31 functional groups, including 21 fish species, 7 invertebrates, 2 primary producers, and a detritus group. The trophic interactions among these groups were analyzed, revealing an average trophic transfer efficiency of 23%. The results indicated that the ecosystem produced more energy than it consumed, with high respiration and consumption rates. Indicators of stability and development were low for the Finn cycle index (13.97), system omnivory index (0.18), and average Finn path length (3.09), indicating a disturbed ecosystem with a linear trophic structure. Keystone species were identified through the use of the keystone index and mixed trophic impact analysis, with demersal invertebrates, zooplankton, and cephalopods found to have a significant impact on other groups.Keywords: Ecopath, food web, trophic flux, Moroccan Mediterranean Sea
Procedia PDF Downloads 931116 Wildlife Communities in the Service of Extensively Managed Fishpond Systems – Advantages of a Symbiotic Relationship
Authors: Peter Palasti, Eva Kerepeczki
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Extensive fish farming is one of the most traditional forms of aquaculture in Europe, usually practiced in large pond systems with earthen beds, where the growth of fish is based on natural feed and supplementary foraging. These farms have semi-natural environmental conditions, sustaining diverse wildlife communities that have complex effects on fish production and also provide a livelihood for many wetland related taxa. Based on their characteristics, these communities could be sources of various ecosystem services (ESs), that could also enhance the value and enable the multifunctional use of these artificially constructed and maintained production zones. To identify and estimate the whole range of wildlife’s contribution we have conducted an integrated assessment in an extensively managed pond system in Biharugra, Hungary, where we studied 14 previously revealed ESs: fish and reed production, water storage, water and air quality regulation, CO2 absorption, groundwater recharge, aesthetics, recreational activities, inspiration, education, scientific research, presence of semi-natural habitats and useful/protected species. ESs were collected through structured interviews with the local experts of all major stakeholder groups, where we have also gathered information about the known forms, levels (none, low, high) and orientations (positive, negative) of the contributions of the wildlife community. After that, a quantitative analysis was carried out: we calculated the total mean value of the services being used between 2014-16, then we estimated the value and percentage of contributions. For the quantification, we mainly used biophysical indicators with the available data and empirical knowledge of the local experts. During the interviews, 12 of the previously listed services (85%) were mentioned to be related to wildlife community, consisting of 5 fully (e.g., recreation, reed production) and seven partially dependent ESs (e.g., inspiration, CO2 absorption) from our list. The orientation of the contributions was said to be positive almost every time; however, in the case of fish production, the feeding habit of some wild species (Phalacrocorax carbo, Lutra lutra) caused significant losses in fish stocks in the study period. During the biophysical assessment, we calculated the total mean value of the services and quantified the aid of wildlife community at the following services: fish and reed production, recreation, CO2 absorption, and the presence of semi-natural habitats and wild species. The combined results of our interviews and biophysical evaluations showed that the presence of wildlife community not just greatly increased the productivity of the fish farms in Biharugra (with ~53% of natural yield generated by planktonic and benthic communities) but also enhanced the multifunctionality of the system through expanding the quality and number of its services. With these abilities, extensively managed fishponds could play an important role in the future as refugia for wetland related services and species threatened by the effects of global warming.Keywords: ecosystem services, fishpond systems, integrated assessment, wildlife community
Procedia PDF Downloads 1091115 Anti-Tyrosinase and Antibacterial Activities of Marine Fungal Extracts
Authors: Shivankar Agrawal, Sunil Kumar Deshmukh, Colin Barrow, Alok Adholeya
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A variety of genetic and environmental factors cause various cosmetics and dermatological problems. There are already claimed drugs available in market for treating these problems. However, the challenge remains in finding more potent, environmental friendly, causing minimal side effects and economical cosmeceuticals. This leads to an increased demand for natural cosmeceutical products in the last few decades. Plant derived ingredients are limited because plants either contain toxic metabolites, grow too slow or seasonal harvesting is a problem. The research work carried out in this project aims at isolation, characterization of marine fungal secondary metabolite and evaluating their potential use in future cosmetic skin care products. We have isolated and purified 35 morphologically different fungal isolates from various marine habitats of the India. These isolates have been functionally characterized for anti-tyrosinase, antioxidant and anti-acne activities. For molecular characterization, the Internal Transcribed spacer (ITS) region of 15 functionally active marine fungal isolates was amplified using universal primers, ITS1 and ITS4 and sequenced. Out of 15 marine fungal isolates crude extract of strains D4 (Aspergillus terreus) and P2 (Talaromyces stipitatus) showed 70% and 57% tyrosinase inhibition at 1mg/mL respectively. Strain D5 (Simplicillium lamellicola) has showed significant inhibition against Propionibacterium acnes and Staphylococcus epidermidis. In addition, all these strains also displayed DPPH- radical scavenging activity and may be utilized as skin cosmeceutical applications. Purification and characterization of crude extracts for identification of active lead molecule is under process.Keywords: anti-acne, anti-tyrosinase, cosmeceutical, marine fungi
Procedia PDF Downloads 2701114 Valorization of Marine Seaweed Biomass: Furanic Platform Chemicals and Beyond
Authors: Sanjay Kumar, Saikat Dutta, Devendra S. Rawat, Jitendra K. Pandey, Pankaj Kumar
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Exploding demand for various types of fuels and gradually growing impacts of atmospheric carbon dioxide have forced the researchers to search biofuels in general and algae-based biofuels in particular. However, strain identification in terms of fuel productivity and over all economics of fuel generation remains a debatable challenge. Utilization of marine biomass, especially the ones important in the Indian subcontinent, in forming furanic fuels and specialty chemicals would likely to be a better value-addition pathway. Seaweed species e.g. Ulva, Sarconema, and Gracilaria species have been found more productive than land-based biomass sources due to their higher growth rate. Additionally, non-recalcitrant nature of marine biomass unlike lignocellulosics has attracted much attention in recent years towards producing bioethanol. Here we report the production of renewable, biomass-derived platform molecules such as furfural and 5-(chloromethyl) furfural (CMF) from a seaweed species which are abundant marine biomass. These products have high potential for synthetic upgradation into various classes of value-added compounds such as fuels, fuel-additives, and monomers for polymers, solvents, agrochemicals, and pharmaceuticals.Keywords: seaweeds, Ulva, CMF, furan
Procedia PDF Downloads 4421113 Self-Calibration of Fish-Eye Camera for Advanced Driver Assistance Systems
Authors: Atef Alaaeddine Sarraj, Brendan Jackman, Frank Walsh
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Tomorrow’s car will be more automated and increasingly connected. Innovative and intuitive interfaces are essential to accompany this functional enrichment. For that, today the automotive companies are competing to offer an advanced driver assistance system (ADAS) which will be able to provide enhanced navigation, collision avoidance, intersection support and lane keeping. These vision-based functions require an accurately calibrated camera. To achieve such differentiation in ADAS requires sophisticated sensors and efficient algorithms. This paper explores the different calibration methods applicable to vehicle-mounted fish-eye cameras with arbitrary fields of view and defines the first steps towards a self-calibration method that adequately addresses ADAS requirements. In particular, we present a self-calibration method after comparing different camera calibration algorithms in the context of ADAS requirements. Our method gathers data from unknown scenes while the car is moving, estimates the camera intrinsic and extrinsic parameters and corrects the wide-angle distortion. Our solution enables continuous and real-time detection of objects, pedestrians, road markings and other cars. In contrast, other camera calibration algorithms for ADAS need pre-calibration, while the presented method calibrates the camera without prior knowledge of the scene and in real-time.Keywords: advanced driver assistance system (ADAS), fish-eye, real-time, self-calibration
Procedia PDF Downloads 2411112 The Mouth and Gastrointestinal Tract of the African Lung Fish Protopterus annectens in River Niger at Agenebode, Nigeria
Authors: Marian Agbugui
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The West African Lung fishes are fishes rich in protein and serve as an important source of food supply for man. The kind of food ingested by this group of fishes is dependent on the alimentary canal as well as the fish’s digestive processes which provide suitable modifications for maximum utilization of food taken. A study of the alimentary canal of P. annectens will expose the best information on the anatomy and histology of the fish. Samples of P. annectens were dissected to reveal the liver, pancreas and entire gut wall. Digital pictures of the mouth, jaws and the Gastrointestinal Tract (GIT) were taken. The entire gut was identified, sectioned and micro graphed. P. annectens was observed to possess a terminal mouth that opens up to 10% of its total body length, an adaptive feature to enable the fish to swallow the whole of its pry. Its dentition is made up of incisors- scissor-like teeth which also help to firmly grip, seize and tear through the skin of prey before swallowing. A short, straight and longitudinal GIT was observed in P. annectens which is known to be common feature in lungfishes, though it is thought to be a primitive characteristic similar to the lamprey. The oesophagus is short and distensible similar to other predatory and carnivorous species. Food is temporarily stored in the stomach before it is passed down into the intestine. A pyloric aperture is seen at the end of the double folded pyloric valve which leads into an intestine that makes up 75% of the whole GIT. The intestine begins at the posterior end of the pyloric aperture and winds down in six coils through the whole length intestine and ends at the cloaca. From this study it is concluded that P. annectens possess a composite GIT with organs similar to other lung fishes; it is a detritor with carnivorous abilities.Keywords: gastrointestinal tract, incisors scissor-like teeth, intestine, mucus, Protopterus annectens, serosa
Procedia PDF Downloads 1381111 Effect of Red Cabbage Antioxidant Extracts on Lipid Oxidation of Fresh Tilapia
Authors: Ayse Demirbas, Bruce A. Welt, Yavuz Yagiz
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Oxidation of polyunsaturated fatty acids (PUFA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in fish causes loss of product quality. Oxidative rancidity causes loss of nutritional value and undesirable color changes. Therefore, powerful antioxidant extracts may provide a relatively low cost and natural means to reduce oxidation, resulting in longer, higher quality and higher value shelf life of foods. In this study, we measured effects of red cabbage antioxidant on lipid oxidation in fresh tilapia filets using thiobarbituric acid reactive substances (TBARS) assay, peroxide value (PV) and color assesment analysis. Extraction of red cabbage was performed using an efficient microwave method. Fresh tilapia filets were dipped in or sprayed with solutions containing different concentrations of extract. Samples were stored for up to 9 days at 4°C and analyzed every other day for color and lipid oxidation. Results showed that treated samples had lower oxidation than controls. Lipid peroxide values on treated samples showed benefits through day-7. Only slight differences were observed between spraying and dipping methods. This work shows that red cabbage antioxidant extracts may represent an inexpensive and all natural method for reducing oxidative spoilage of fresh fish.Keywords: antioxidant, shelf life, fish, red cabbage, lipid oxidation
Procedia PDF Downloads 3201110 Assessment of Water Pollution in the River Nile (Egypt) by Applying Blood Biomarkers in Two Excellent Model Species Oreochromis niloticus niloticus and Clarias gariepinus
Authors: Alaa G. M. Osman, Abd-El –Baset M. Abd El Reheem, Khaled Y. Abouelfadl, Usama M. Mahmoud, Mohsen A. Moustafa
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This study aimed to explore new sites of biomarker research and to establish the use of blood parameters in wild fish populations. Four hundred and twenty fish samples were collected from six sites along the whole course of the river Nile, Egypt. The mean values of erythrocytes, thrombocytes, hemoglobin concentration, hematocrit value, and mean corpuscular volume were significantly lower in the blood of Nile tilapia and African catfish collected from downstream (contaminated) compared to upstream sites. In contrast, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration in the peripheral blood of both fish species significantly increased from upstream to downstream river Nile. The leukocytes count was significantly decreased in contaminated sites compared to upstream area. Hematological variables in the peripheral blood of Oreochromis niloticus niloticus and Clarias gariepinus exhibited significant (p<0.05) correlation with nearly all the detected chemical and physical parameters along the Nile course. In the present study, lower cellular and nuclear areas and cellular and nuclear shape factor were recorded in the erythrocytes of fish collected from downstream compared to those caught from upstream sites. This was confirmed by higher immature ratios of red cells in the blood of fish sampled from downstream river Nile. Karyorrhetic and enucleated erythrocytes were significantly correlated with physiochemical parameters in water samples collected from the same sites is being higher in the blood of fish collected from downstream sites. To see if there was any correlation between fish altered physiological fitness and environmental stress, we measured serum biochemical variables namely; total protein, cholesterol, triglycerides, calcium, chlorides, alkaline phosphatase activity (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), uric acid activity, creatinine, and serum glucose. The level of all the selected biochemical variables in the blood of O. niloticus niloticus and C. gariepinus were recorded to be significantly higher (p<0.05) in downstream sites. According to the present results, nearly all the detected haematological and blood biochemical variables are suitable indicators of contaminant exposure in O. niloticus niloticus and C. gariepinus. Also the detected erythrocytes malformations in blood collected from Nile tilapia and African catfish were proven to be suitable for bio-monitoring aquatic pollution. The results revealed species-specific differences in sensitivities, suggesting that Nile tilapia may serve as a more sensitive test species compared to African catfish.Keywords: biomarkers, water pollution, blood parameters, river nile, african catfish, nile tilapia
Procedia PDF Downloads 2851109 Synergetic Effect of Dietary Essential Amino Acids (Lysine and Methionine) on the Growth, Body Composition and Enzymes Activities of Genetically Male Tilapia
Authors: Noor Khan, Hira Waris
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This study was conducted on genetically male tilapia (GMT) fry reared in glass aquarium for three months to examine the synergetic effect of essential amino acids (EAA) supplementation on growth, body composition, and enzyme activities. Fish having average body weight of 16.56 ± 0.42g were fed twice a day on artificial feed (20% crude protein) procured from Oryza Organics (commercial feed) supplemented with EAA; methionine (M) and lysine (L) designated as T1 (0.3%M and 2%L), T2 (0.6%M and 4%L), T3 (0.9%M and 6%L) and control without EAA. Significantly higher growth performance was observed in T1, followed by T2, T3, and control. The results revealed that whole-body dry matter and crude protein were significantly higher (p ≤ 0.05) in T3 (0.9% and 6%) feeding fish, while the crude fat was lower (p ≤ 0.05) in a similar group of fish. Additionally, protease, amylase, and lipase activities were also observed maximum (p ≤ 0.05) in response to T3 than other treatments and control. However, the EAA, especially lysine and methionine, were found significantly higher (p ≤ 0.05) in T1 compared to other treatments. Conclusively, the addition of EAA, methionine, and lysine in the feed not only enhanced the growth performance of GMT fry but also improved body proximate composition and essential amino acid profile.Keywords: genetically male tilapia, body composition, digestive enzyme activities, amino acid profile
Procedia PDF Downloads 1401108 Study on the Effect of Vitamin D on the Biochemical Parameters in Cyprinus carpio
Authors: Mojdeh Chelemal Dezfoul Nejad, Ali Mohammadzadeh Shobeagar, Mehrzad Mesbah
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This study was conducted in order to characterize the different levels of dietary vitamin D on some of biochemical parameters of Cyprinus carpio. For this purpose, 180 pieces of Cyprinus carpio with an average weight of 20-25 grams were divided into four treatments and each treatment was divided into three replications and treatments were fed at three different doses (1000 IU, 3000 IU, 5000 IU) of vitamin D for 60 days. The fish were fed 3% of their wet b.wt. per day for a 60 days period. Blood samples were obtained from six fish of each tank at the end of experiment. Based on the results significant difference was observed on the mean amount of total protein, urea, glucose and cholesterol between treatments (p < 0.05). But, there was no significant difference in the mean amount of triglyceride and albumin with the different diets designed for this experiment (p > 0.05).Keywords: Cyprinus carpio, vitamin D, biochemical parameters, glucose
Procedia PDF Downloads 3421107 Navigating Rough Seas: A Qualitative Exploration of National Sociotechnical Imaginaries of Myanmar’s Future Marine Fisheries
Authors: Hannes Groeneweg
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Myanmar is considered one of the largest fishing nations in the world. The country’s rapid economic and political reform process since 2011 entails both challenges and opportunities for its marine fishing sector. The development pathway of the sector remains unclear. Which future will eventually materialize is shaped and determined by the various visions and actions of the stakeholders engaging in political debates and decision-making. These visions can be conceptualized through the Science and Technology Studies (STS) concept of sociotechnical imaginaries. The research of this article is guided by the question of which imaginaries are currently relevant, who is propagating these imaginaries, and how are these imaginaries produced and contested. Using qualitative documentary analysis of policy documents, reports, and media articles as well as in-depth interviews with key stakeholders, three archetypical national sociotechnical imaginaries of Myanmar’s future marine fisheries were identified: The industrial scale extractivism imaginary views marine fishing sector as a driver for national economic growth and focuses on the industrial and technological development of the production chain, increasing yield and exports. Sustainable fishing management encompasses the vulnerability of marine ecosystems and views increasing efficient sustainability governance, planning, and management into existing fishing practices. In the traditional sufficiency fishing imaginary, small-scale fishing practices are viewed as an important livelihood practice for millions of coastal dwellers. The need to conserve them through strengthening the self-reliance, autonomy, and resilience of these communities is stressed. In national debates, the first two imaginaries are currently dominant. The imaginaries, as well as their contestations, are also linked to other critical political issues. The paper suggests that participatory decision-making processes are needed to create an inclusive imaginary of the future marine fishing sector.Keywords: science and technology studies, sociotechnical imaginaries, marine fishing, knowledge coproduction, Myanmar
Procedia PDF Downloads 1701106 Sampling Error and Its Implication for Capture Fisheries Management in Ghana
Authors: Temiloluwa J. Akinyemi, Denis W. Aheto, Wisdom Akpalu
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Capture fisheries in developing countries provide significant animal protein and directly supports the livelihoods of several communities. However, the misperception of biophysical dynamics owing to a lack of adequate scientific data has contributed to the suboptimal management in marine capture fisheries. This is because yield and catch potentials are sensitive to the quality of catch and effort data. Yet, studies on fisheries data collection practices in developing countries are hard to find. This study investigates the data collection methods utilized by fisheries technical officers within the four fishing regions of Ghana. We found that the officers employed data collection and sampling procedures which were not consistent with the technical guidelines curated by FAO. For example, 50 instead of 166 landing sites were sampled, while 290 instead of 372 canoes were sampled. We argue that such sampling errors could result in the over-capitalization of capture fish stocks and significant losses in resource rents.Keywords: Fisheries data quality, fisheries management, Ghana, Sustainable Fisheries
Procedia PDF Downloads 821105 Development of Anti-Fouling Surface Features Bioinspired by the Patterned Micro-Textures of the Scophthalmus rhombus (Brill)
Authors: Ivan Maguire, Alan Barrett, Alex Forte, Sandra Kwiatkowska, Rohit Mishra, Jens Ducrèe, Fiona Regan
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Biofouling is defined as the gradual accumulation of Biomimetics refers to the use and imitation of principles copied from nature. Biomimetics has found interest across many commercial disciplines. Among many biological objects and their functions, aquatic animals deserve a special attention due to their antimicrobial capabilities resulting from chemical composition, surface topography or other behavioural defences, which can be used as an inspiration for antifouling technology. Marine biofouling has detrimental effects on seagoing vessels, both commercial and leisure, as well as on oceanographic sensors, offshore drilling rigs, and aquaculture installations. Sensor optics, membranes, housings and platforms can become fouled leading to problems with sensor performance and data integrity. While many anti-fouling solutions are currently being investigated as a cost-cutting measure, biofouling settlement may also be prevented by creating a surface that does not satisfy the settlement conditions. Brill (Scophthalmus rhombus) is a small flatfish occurring in marine waters of Mediterranean as well as Norway and Iceland. It inhabits sandy and muddy coastal waters from 5 to 80 meters. Its skin colour changes depending on environment, but generally is brownish with light and dark freckles, with creamy underside. Brill is oval in shape and its flesh is white. The aim of this study is to translate the unique micro-topography of the brill scale, to design marine inspired biomimetic surface coating and test it against a typical fouling organism. Following extensive study of scale topography of the brill fish (Scophthalmus rhombus) and the settlement behaviour of the diatom species Psammodictyon sp. via SEM, two state-of-the-art antifouling surface solutions were designed and investigated; A brill fish scale bioinspired surface pattern platform (BFD), and generic and uniformly-arrayed, circular micropillar platform (MPD), with offsets based on diatom species settlement behaviour. The BFD approach consists of different ~5 μm by ~90 μm Brill-replica patterns, grown to a 5 μm height, in a linear array pattern. The MPD approach utilises hexagonal-packed cylindrical pillars 10.6 μm in diameter, grown to a height of 5 μm, with vertical offset of 15 μm and horizontal offset of 26.6 μm. Photolithography was employed for microstructure growth, with a polydimethylsiloxane (PDMS) chip-based used as a testbed for diatom adhesion on both platforms. Settlement and adhesion tests were performed using this PDMS microfluidic chip through subjugation to centrifugal force via an in-house developed ‘spin-stand’ which features a motor, in combination with a high-resolution camera, for real-time observing diatom release from PDMS material. Diatom adhesion strength can therefore be determined based on the centrifugal force generated at varying rotational speeds. It is hoped that both the replica and bio-inspired solutions will give comparable anti-fouling results to these synthetic surfaces, whilst also assisting in determining whether anti-fouling solutions should predominantly be investigating either fully bioreplica-based, or a bioinspired, synthetically-based design.Keywords: anti-fouling applications, bio-inspired microstructures, centrifugal microfluidics, surface modification
Procedia PDF Downloads 3101104 Biochemical Assessments of the Effects of Crude Oil Contaminated Diets Wistar Rats
Authors: Olawuyi Sikiru Owolabi
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A research was carried out to assess the biochemical effects of crude oil contaminated cat fish on selected rat kidney function tests. Thirty-six (36) albino rats (rattus novergicus) were grouped into six (6) of (6) in each group. The rats in group one served as control and they were placed on feed formulated with catfish cultured in borehole water while those ones from group 2 to group 6 were placed on feed formulated with catfish exposed to various concentrations of crude oil (0.1%,0.25%,0.5%,0.75% and 1% respectively).The results obtained showed that there was a significant increase in serum concentration of creatinine, Urea, sodium and potassium ions in the kidney of experimental rats when compared with the control. This may be interpreted to mean possible adverse effects on the kidney. Several studies have been done especially on the biological effects of crude oil in fish. These include Direct Lethal Toxicity, Sub-Lethal disruption of physiological and behavioral activities, interference with feeding and reproduction, direct coating or tainting of fish, effect of entry of hydrocarbons into the food web as well as alteration of biological habitat. The present study attempts to assess the effects of crude oil contaminated diet on rat kidney by carrying out some kidney function tests like determination of serum sodium and potassium ions by flame photometry method, determination of serum urea and determination of serum creatinine.Keywords: crude oil, serum urea, creatinine, wistar rats
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