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ICT: extending the ripples
Get PDFThe use of information and communication technologies (ICTs) can help promote equitable and sustainable small-scale fisheries, a workshop in Cape Town, South Africa, stressed
Culcita novaeguineae (Müller & Troschel, 1842)
Get PDFCulcita novaeguineae or cushion star is a species of starfish. It has short arms and an inflated appearance and resembles a pentagonal pincushion. It is variable in colour and can be found in tropical warm waters in the Indo-Pacific. C. novaeguineae is living coral reefs at reef edge and slope at depths of 1 to 20 m. We report for the first time from Bali Waters (Indonesia). This species has exhibited a slight preference for the coral Acropora spp. over Poccilopora spp. and Porities spp. A mature C. novaeguineae is pentagonal in shape with an inflated appearance and much-abbreviated arms. It can grow to a diameter of 30 cm. Rows of tube feet are on the underside, and it has a central mouth. The color is very variable and includes a mottling with darker and lighter shades of fawn, brown, orange, yellow and green. The armored body wall is made of calcareous ossicles which are supported internally by pillars which buttress the ambulacra. The armouring contains pits into which the tube feet can be retracted. The body cavity is filled with water. Small cushion stars are very different in appearance. They are star-shaped, with five short, broad arms and a low profile. As they grow, the inter-arm areas fill in and expand relative to the tube-feet areas, and the arms get shorter relative to the disc which becomes inflated and more massive
SSF: legislation towards apt instruments
Get PDFThe relevance of including small-scale fisheries in fisheries legislation and instruments cannot be overemphasized, even if the issue is rather complicated
Canada: human rights, rightfully unfair
Get PDFThe treatment of the commercial salmon fishermen along the west coast of Canada, through the unprincipled actions of their own government, is driving them into bankruptcy
Latin America: Brazil: Building knowledge
Get PDFA report on the 13th Women’s World and Fazendo Gênero 11 held in Brazil recently
Monitoring on algal bloom event in the southern of Caspian Sea
Get PDFNutrient enrichment is followed by excessive algal growth (possible in toxic and harmful species); in Caspian Sea in recent decades. So aims of the present study were 1-study on potential of algal bloom at different transects and seasons, 2- determine correlation between potential of algal bloom and environmental parameters using statistical model, and 3- the role of sediment nutrients on algal bloom in the southern Caspian Sea in 2013-2014. The samples of water were collected from four transests (Bandar Anzali, Tonekabon, Bandar Nowshahr and Bandar Amirabad) and three depths (5, 10 and 20 meter) during four seasons. Surface sediments samples were collected at same depths and transects as well. Result showed that organic phosphorous and nitrogen of water were more than inorganic phophorous and nitrogen. Also, maximum and minimum water temperature was obtained at summer and winter, respectively. The values of DO and salinity were more than 5 ml/l and 12 g/l, respectively and pH of water were ranged from weak alkaline to alkaline. Maximum organic and inorganic phosphorous and nitrogen of water were distributed at different transects and seasons. The nitrogen was limiting factor accomponing with phosphorous during spring, summer and fall, but during winter shift to more nitrogen limitation. In addition, the ecosystem was experienced sillicon limitation during winter. Result of sediments showed that inorganic phophorous was maximum during different seasons, however, percent mean of residue-P which contain organic compounds and non-degrediable compounds, was less that 5 percent. Percent of Ca-P was higher than 90, whereas Bioava.-P was less that 10 percent. The order of different forms of phosphorous were registered Ca-P>Org-P>Fe-P>Al-P>Loosely-P. The mian role of adsorbed and desorbed of Loosely-P, Fe-P and Al-P were due to temperature, Eh and pH, respectively. Annual percent of TON was two folds than TIN and NH4/N was also three times than NO_3/N. Minimun and maximum of phytoplankton abundance were obserbed in summer (73±31 million cells/m3) and winter (505±55 million cells/m3), respectively. Statiscal analysis (ANOVA) showed that phytoplankton abundance significantly increased in winter compared to the other seasons (P1000 cells/ml) during spring. Maximum abundance of phytoplankton was mainly registered at Anzali and Amirabad transects.The re-existence of Thalassionema nitzschioides (as valuble food in food chain) in dominant species list (same as the stability year of ecosystem) and decreasing of percent abundance of harmful species to the dewell and native species are good sign of good quality of the Caspian Sea water. However, Pseudonitzschia seriata expansion of the cold season to other seasons (even in summer) is important point. Pseudonitzschia seriata as harmful algae and its ability to produce toxin and potential bloom, high percent frequency and abundance during the study has important role in environmental issues of the Caspian Sea.It seems that temperature changes in different parts of the Caspian Sea in each season (except fall season) was obtained in the range of dominant species needed, therefore, it had less importance compared to nutrients. Trophic status was meso-eutroph during fall and winter seasons which was higher level than spring and summer (mesotroph). The Stephanodiscus abundance increased at Anzali transet due to nutrients enrichment of water in spring. Excessive use of silica in the spring, summer caused dominant of non Diatoms species (Binuclearia lauterbornii) and low content of Diatoms species (Chaetoceros throndsenii). In fall, high abundance of Bacillariophyta (Thalassionema nitzschioides) accompanied with consuming of silicon and ammonium. The statistical analysis also showed significant correlation between Bacillariophyta and Thalassionema nitzschioides abundance and Si/N ratio. Subsequently, the excessive use of silica in autumn and winter (due to high abundance Bacillariophyta and dominant species including Pseudonitzschia seriata and Dactyliosolen fragilissima) cause severely declined dissolved silica, and for the first time in winter, silicon was limited factor for phytoplankton growth. In addition, the results showed that there were positive correlations between abundance of dominant species and nutrients of sediments in all seasons. This is shows that some species of phytoplankton, even though the limitation of nitrogen and phosphorus in the water, are able to supply the nutrients required from the surface sediments. It would be more importance in the present study, which higher concentration of different forms of phosphorus and nitrogen in sediments as compared to the deep water, provide transport of nitrogen and phosphorus from sediment to water column
Environmental impact assessment (EIA) on cultivation of the nile tilapia (Oreochromis niloticus) with brackish water in Dashtestan
Get PDFEIA is a worthy tool for identifying and assessing potential impacts and control them.it compatibles environmental aspects with sustainable development. In order to predict the effects of tilapia culture activities on regional we gathered physical, biological, and social information to quantify the activities effects on them. We addressed 42 impacts consist of 31 positive, and 11 negative. These affect half of social, 33% of physical, and 17 of biological elements. This equivalent with -42, +304, and+36 when puts in the charts.in order to have a good and comprehensive assessment of activities Leopold matrices was employed. Based on summarized values from this we have +380and -82 results +298. This means that this activity has a great positive result especially on socio-economic environment. These kinds of studies are highly recommended for other parts of the Bushehr province e.g Dashtestan county that most of their water resources are brackish and not suitable for agriculture
Monitoring and identification of viral pathogens in SPF (Specific Pathogen Free) shrimp production project
Get PDFShrimp aquaculture has developed rapidly in 1980s decade and this development caused to increase shrimp diseases in farms. In the last 0f 1980s and first of 1990s find of health shrimp Postlarvae for stocking was hard. In Iran also after two decades diseases are the main problems, then a national project (Shrimp SPF production) was performed that this section was monitoring and identification of viral pathogens in that project. For this propose selected shrimps in farms was sampled and screened for main viruses (OIE list), shrimps without infection bring to quarantine system for one month and in the end of quarantine period were screened again. Then in winter spending, before and after spawning, it’s offspring in F1 and F2 also screened for viral pathogens by IQ2000 kit in Iranian veterinary organization lab. Moreover all shrimp feeds in clouding: fresh feed, live feed and pellet feed had been screened for OIE viral pathogens listed for three years. Results of viruses screening in shrimp sampled in all stages of project and feed that use in this project were negative. This project (SPF shrimp production in IRAN) performed successfully, we think this success relate to biosecurity system that were influence in this project