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Poverty: come together
Get PDFOnly collective action in small-scale fisheries can overcome the problems of poverty, marginalization, insecure tenure rights and powerlessness
Gender: Where have all the women gone?
Get PDFSex-segregated employment data in the recently released State of World Fisheries and Aquaculture 2018 report points to the need for better and more standardised data collection
Comparing modeling of pollution in Arvand River in the dry and wet seasons
Get PDFWater resources under threat of pollution such as industrial waste, fertilizers, pesticides and urban sewage that negative effects on the environment and ecosystems. Arvand River is one of the most important navigable rivers in Iran، and it’s the most traffic place for floating which don’t have any system for delivery waste materials and discharging these waste materials in water making oil pollution. In this research, modeling pollution in the Arvand River using three-dimensional and hydrodynamic model to simulate how the pollution is studied, the Navier-Stokes equations in three dimensions and equations are solved transfer salinity and water temperature separation method. Boundary conditions applied، including changes in temperature، salinity and flow rate، temperature and salinity changes and apply for open border river and tidal components O1، S2، M2 and K1 open sea in the model used for the border. In this research, modeling pollution in the Arvand River using coherence and hydrodynamic modeling to simulate how the pollution is studied. The results of modeling pollution in Arvand After running the model revealed that the pollution is pollution in the Arvand River according to location and time of release، in other words، in the Arvand River pollution from one point to another and from season to season is different، in fact، pollution is reciprocating mode. Diffusion of oil pollution in Arvand rood is depending to current. In low tide because of same side of river current is more. And in low tide because of same side of river current with low tide pollution reached to the Persian Gulf with high speed. The results shows, represent the effect of tie on diffusion pollution
A study on some microbial indices and nutrient matters in the southern part of Caspian Sea; Guilan province
Get PDFThe microbial pollutions and nutrient matters of the southern part of Caspian Sea is to be under close scrutiny as it is vital to tourist health and environmental conservation. In this research, some physico-chemical factors, nutrient matters, oxygen demand parameters and microbial indices were investigated. Sampling from nine sites along Astara to Chaboksar coastline were conducted with five replicates. The mean of temperature, Salinity, pH, phosphate, and nitrate, FC, TC, BOD5 and COD were respectively obtained as 22.48°C, 8.5ppt, 8.27, 0.43mg/l, 2.21mg/l, 144MPN/100ml, 626.9MPN/100ml, 3.58mg/l and 9.43 mg/l. Maximum levels of nutrient matters were measured at Anzali and Kiyashahr sites. Results showed there are positive correlations between nutrient matters as well as COD with microbial indices. The average of microbial indices at nine sampling sites were higher than the permissible level of national and international organizations for swimming places. Due to high level of microbial pollution at Anzali and Chobar sampling sites, the swimming places of these areas require specific administration
Measurement of the lethal concentration of thyme essential oils in rainbow trout (Onchorhynchus mykiss)
Get PDFThe importance of the use of medicinal plants against infectious and non-infectious diseases is completely obvious. The replacement of synthetic drugs due to their multiple properties in the prevention and treatment of many diseases, particularly in the aquaculture industry seems to be very important. This study was performed with the aim of assessing the acute toxicity (LC_50-96) of thyme essential oil on rainbow trout. To study the effect of the essential oils, 80 premature rainbow trout with an average weight of 10±0.5 in 9-liter tanks were exposed to different concentrations of essential oils of thyme and daily losses based on OECD protocol were calculated during 96 hours. All the physical and chemical factors such as water temperature, dissolved oxygen, pH, nitrite, nitrate, ammonium levels, electrical conductivity and water hardness were measured in different treatments. The acute toxicity of the essential oil of thyme was calculated using probit analysis and a concentration of 4.4 ppm was determined
Zooplankton of Çat Dam Lake (Malatya-Turkey) with a new record for Turkish rotifers Lecane intrasinuata (Olofsson, 1917)
Get PDFThere are many studies on the zooplankton of Turkish lakes, many of which are about seasonal fluctuations, distribution and hydrological changes. In recent years many scientists focused their attention on the zooplankton of Turkish inland waters (Dumont and De Ridder, 1987; Segers et al., 1992). The family Lecanidae consists of one genus, Lecane Nitzsch, 1827 with about 200 species. This genus is the most common rotifer species inhabiting in various aquatic environments (Segers 1994, 1995, 2008). They are from Monogonont rotifers and are diagnosed by the retractile head, the structure of the foot and toes and by the trophy in the female (Segers, 1995). Lecanids have got a loricate body and the body is compressed dorso-ventrally. The dorso ventral plates are connected by a flexible membrane. The feet have got two primitive segments of which only the posterior is movable. Toes varied remarkably within individuals of the same species (Arora, 1965). Their bodies resemble each other which cause difficulties in identifying species (Segers et al., 1992).
Brazil: SSF, endless conflicts
Get PDFThe access of Brazil's fishers to coastal land and sea resources has, in recent years, been hampered by increased urbanization, tourism and construction of harbour
Effect of enriched rotifer (Brachionus plicatilis) with probiotic lactobacilli on growth, survival and resistance indicators of western white shrimp (Litopenaeus vannamei) larvae
Get PDFThis study examined the effects of a commercial Lactobacillus probiotic on growth, survival and resistance of western white shrimp (Litopenaeus vannamei) larvae against salinity and formalin stresses in the Persian Gulf and Oman Sea Ecology Research Center. In this experiment, larvae were fed 6 times a day from mysis I (M1) step to post larvae 5 over 3 treatments including a control treatment C (without probiotic) and 2 experimental treatments namely A (having probiotic enriched rotifer) and B (having probiotic enriched rotifer and adding probiotic powder directly to the water). Larvae were stocked in 9 plastic tanks (20-liter) containing 10 L of seawater at a density of 50 larvae per liter. Three replicates were used for each treatment. At the end of the experimental period biometric larvae were studied under salinity and formalin stresses. Results showed that using probiotic bacteria had significant and positive effects on shrimp resistance, survival and growth (p0.05). According to the results we may conclude that the use of probiotic powder is effective in increasing growth, survival and resistance rate of western white shrimp in the larval and post larval stages