جستجوی مقالات مرتبط با کلیدواژه "پساب" در نشریات گروه "شیلات"

Agricultural effluents contain nutrients such as phosphates, nitrates and ammonia, which cause surface and underground water pollution. By absorbing these nutrients, freshwater algae such as Spirulina can play an important role in reducing these types of pollutants. On the other hand, this type of wastewater, having nutrients, can be used as an alternative and cheap substrate for algae cultivation. Five concentrations of diluted sugarcane effluent (0, 25, 50, 75, and 100%) were prepared with Zarrouk’s medium and the growth rate, photosynthetic pigments, and the amount of some mineral substances, protein, and fat composition were evaluated. In high concentrations of wastewater (75 and 100% wastewater treatment), a very good growth of Spirulina was observed.The amount of chlorophyll a in the treatment of 100% of wastewater showed a significant increase compared to the control treatment (p < 0.05). The maximum amount of total carotenoids in the treatment of 50% of the Zarrouk’s medium was obtained at the rate of 1559 ± 226 mg/liter, which was more than 2 times the amount of total carotenoids in the control treatment. The maximum amount of total carotenoid in the treatment of 50% of Zarrouk’s medium was 1559 ± 226 mg/liter, which was more than 2 times the amount of total carotenoid in the control treatment.In addition, the produced algae can be used as livestock and aquatic food.

The attention to the control of aquatic ponds and the optimum use of water consumption can reduce pollution of the environment and maintenance ecological conditions of the region. This study investigated the effect of artificial wetlands on the reduction of ammonia and nitrate factors and also physical and chemical changes loading in wastewater to improve water efficiency in stellate sturgeon ponds over a ten-month growth period. To conduct this research, 5 ponds (4 m-2) and 5 cement canals were used. Three fiberglass ponds were used to culture of stellate sturgeon under the same conditions, two fiberglass ponds were used for culturing of Hediste diversicolor and Gammarus (Gammarus aequicauda) larvae, and cement channels were used to establish reed plants (Phragmites australis) in the treatments in the first to third rows, respectively. At this study was used 50% recyclution water and 50% freshwater. The ammonia and nitrate factors were measured in all ponds monthly. In the output of the reed plant, the highest percentage of ammonia (NH3-N) and nitrate (NO3-N) removal was related to the water that was passed through the gammarus ponds and stellate sturgeon, respectively. The results of percentage reduction of wastewater nutrients among the treatments showed that the highest ability to remove ammonia (15.6%), and nitrate (24%), was observed in the ponds of Phragmites australis and it also economically plays an important role due to the lack of food cost for feeding worms and Gamarus.

Nutrients in wastewater enrich the environment and cause environmental problems in aquatic environments. Conventional wastewater treatment systems are not capable of removing phosphorus effectively.  The  entry  of  phosphorus  into  water  resources  leads  to  the  formation  of  an Eutrophication  phenomenon. Micro-algae have been more effective among the various methods used for the removing of nutrients from wastewater. Wastewater biological-treatment using algae to eliminate nitrogen and phosphor and produce oxygen for aerobic bacteria is a new trend that has drawn a great deal of attention. Using sunlight, microalgae consume nutrients in wastewater and convert them into useful biomasses. Wastewater biological-treatment using microalgae was studied. Treatment efficiency of micro-algae depends on the species, algae mass concentration, aeration level, and the optimal time to maximize algae activity on wastewater.

In this study, the effect of the effluent from rainbow trout ponds was investigated on the yield, concentration and uptake of nitrogen, phosphorus and micronutrients on the silage corn in the Golpayegan research station for Husbandry and Agriculture in Isfahan. 45000 fish with an average weight of 10 ± 2 g were uniformly divided in 9 ponds (20 × 2.2 × 1.3 m) for six months. The research was conducted in a complete randomized block design with five treatments in triplicate. The treatments were included 1) irrigation with well water without any fertilizer as the control, 2) irrigation with well water and use of urea, triple superphosphate and potassium sulfate as the fertilizers, 3) irrigation with fish ponds effluents without any fertilizer, 4) irrigation with fish ponds effluents and use of the fertilizer, and 5) irrigation with fish ponds effluents with 50 percent of the fertilizer. Results showed that the use of fish ponds effluents significantly caused increasing in corn yield and concentration of zinc, cupper, nitrogen, phosphorus, manganese and iron (p<0.05). In addition, using fish ponds effluents with the 50% of chemical fertilizer led to increase corn yield by 44 percent compared to the control group (p<0.05). Moreover, the uptake of iron, zinc, copper and manganese by corn were increased significantly compared to the control group through use of fish ponds effluents water with fertilizer (p<0.05). The highest and lowest yield of corn was obtained in the irrigation with the effluent of fish ponds effluents coupled with chemical fertilizers and the control group, equal to 73.7 and 44.4 tons per hectare, respectively, which had significant difference with each other (p<0.05). Therefore, the use of fish farm effluents for production of corn not only increased the yield but also dramatically enhanced fertilizer utilization.

The aim of this study was investigating the antimicrobial activity of microalgae Sandosmus and Spirulina cultivated in the BG-11 culture medium and the effluent of the desalination facility of Bandar Turkmen unit, Golestan province, in inhibiting the growth of Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. Algae were extracted by water-alcohol method in proportion (500cc of alcohol and 50cc of distilled water) and determination of minimum inhibitory concentration (MIC) was checked by broth micro dilution method (96 house plates), and were compared to their usual environment with the amount of antibacterial activity grown in water. The results of two mentioned bacteria in the presence of different concentrations of aqueous-ethanolic extract within 24 hours showed that in the extract of the genus Sandosmus and Spirulina grown in BG-11 culture medium and 50 and 100% effluent dilutions, there was no antibacterial effect against Escherichia coli and Staphylococcus aureus bacteria during (24 hours). Sandosmus extract grown in BG-11 with 25 and 50 concentrations had higher E. coli bacteria volume than spirulina in the early hours. As the concentration increases, the volume of bacteria decreases in the early hours. Spirulina extract grown in BG-11 showed high resistance to Staphylococcus bacteria in the early hours compared to Sendesmus. Sendesmus extract grown in 50% wastewater compared to Spirulina had the highest amount of E. coli bacteria in the final hours, so it showed a high resistance to E. coli compared to spirulina. Also, in the extract of Sandosmus grown in 50% wastewater at concentrations of 25, 100 and 200 mg/ml in the final hours, the volume of Staphylococcus bacteria was higher than the concentration of 50 mg/ml, and in spirulina there was a constant trend in the final hours. In both extracts grown in 100% wastewater against E. coli bacteria in all concentrations within 4 hours, they showed the highest amount of bacteria. Therefore, in all concentrations of both extracts, they showed an increase in the volume of Staphylococcus bacteria over time (2-4 hours). Therefore, spirulina grown in 100% wastewater had a stable trend in the last hours compared to Sandosmus and showed more resistance to staphylococcus.

Tetraselmis tetrathele is a species of saltwater that is widely used in industry and aquaculture due to its high nutritional value, bioactive compounds, and ease of cultivation. In this study, mass cultivation of this species was evaluated using effluent from dairy and yeast factories to evaluate growth, viability, and biochemical compounds (protein, fat, carbohydrate). The experiment was performed in a completely randomized design with six treatments; Conway, raw milk and yeast effluents as culture media, each in two modes, diluted (5 ml per liter of culture medium) and concentrated (10 ml per liter of culture medium) for 11 days. The results showed that this species was able to grow on dairy and yeast wastewaters, but the highest cell density in diluted Conway (9.12 × 106 cells per ml and 0.87 per day) and the highest specific growth rate in diluted yeast (6.68 × 106 cells per ml and 2.84 per day) were measured. However, the diluted raw dairy treatment had more survival than other treatments. The highest amount of protein and fat was obtained in the concentrated dairy treatment (44.6% and 9.71% of dry weight, respectively) and the highest amount of carbohydrates was obtained in the concentrated yeast treatment (31.49% of dry weight). Based on the specific growth rate, viability, and biochemical compositions it can be concluded that dairy and yeast wastewaters can be used as a suitable semi-industrial culture medium for mass cultivation of this species and it is recommended for the production of bioactive compounds and biofuels from the obtained biomass.

One of the main requirements in wastewater treatment is the need to remove nutrients, especially nitrogen and phosphorus, which can lead to eutrophication of these sources if they are discharged to water sources. In this study, the application of dairy effluent in the cultivation of Spirulina platensis was studied with the aim of treatment and removing nutrients and also the amount of biomass produced. Thus, two concentrations of Spirulina platensis (0.05 and 0.1 g/l) were cultured in three dilutions (25, 50, 75%) of dairy effluent. The results showed that both factors of different concentrations of microalgae and different dilution of effluent had an important role in nutrient absorption and biomass production. The highest percentages of nitrate, phosphate, ammonia removal (98.03, 74.14, 97.44%) as well as maximum biomass (920 ± 0.09 g/l) were related to 25% dilution of the effluent and secondary microalgae concentration. In fact, the secondary concentration of microalgae (0.1 g/l) performed better than the primary concentration (0.05 g/l) and succeeded in removing higher amounts of nutrients. Thus, dairy effluent is a suitable culture medium for the growth of Spirulina platensis and by reducing the dilution percentage from 75% to 25% and increasing the amount of available nutrients, the amount of biomass increases.

Water pollution is a major global problem that affects plants and living organisms. Factors affecting water pollution include industrial, agricultural, and human pollutants. Qarasu river is very important in terms of pollution due to the use of river water in the agriculture and aquaculture sectors. In this research, the effect of intensive fish farms and the riverbed material was investigated on the abundance of macrobenthic communities. For this purpose, four stations 1) the station upstream and before the fish farms (as control station), 2) the station between the fish farms, 3) the last station of the farms, and 4) the downstream station at a distance of 4 km from the last farm were selected. A sampling of the macrobenthos and riverbeds was done in two seasons, winter and spring, and their frequency was calculated in the sampling stations and months. The highest abundance was related to the family’s Chironomidae (1456 numbers per m2) and Simolidae (2737 numbers per m2) from the Diptera order, which were observed in the effluent of station 2 and station 4 in the winter season, respectively. In addition, the type of the river bed was determined to find the correlation with macrobenthic species. The identified macrobenthos was classified into trophic groups and the relationship with the type of substrate was determined using the Pearson correlation. The correlation of different macrobenthic species with sampling stations and months was found using Canoco software and CCA statistical analysis. The present study showed that the effluent from intensive fish farms had an effect on the abundance of macrobenthos in the Qarasu River, which could be due to the increase in nutrients in the river water from the release of the effluent, and decrease in temperature and decrease in the decomposition of nutrients in the winter season. Therefore, based on the findings, the presence of different functional macrobenthic groups is affected by the type of riverbed and different seasons of the year.

Wastewaters contain nutrients that can be used as culture media for microalgae. In this study, density, growth, and biochemical compositions (protein, lipid and carbohydrates) of Tetraselmis tetrathele were investigated using mollasse and beer wastewater. A completely randomized experimental design was performed containing treatments; Conway, mollasse, and beer wastewater in two concentrations of diluted (5 ml per liter of culture medium, v/v), and concentrated (10 ml per liter of culture medium, v/v) over a 11-day period. The highest cell density was obtained in the concentrated mollasse treatment (96.7×103 cells per ml) and the highest specific growth rate obtained in the dilute Conway treatment (15.5 per day). In addition, the highest amount of protein and lipid (39.5% and 8.1%, respectively) was measured in the concentrated beer treatment and the lowest recorded in the concentrated Conway treatment (10.70% and 2.98%, respectively). The highest amount of carbohydrates (28.92%) was obtained in diluted mollasse treatment. Therefore, based on the results of growth rate and biochemical compositions of T. tetrathele, it can be concluded that the beer and mollasse wastes are suitable media for growth of T. tetrathele..

Aquaculture development and construction materials have reduced water health. In this study, we have measured the water quality parameters of Mohammad Abad River, has a mean role in flood control, Fazelabad water supply and ecological balance, compared it with surface water standards. The value of Water Temperature, Turbidity, Dissolved Solids, Salinity (EC), Phosphate, Nitrate, Nitrite, Ammonia, Dissolved Oxygen, pH, BOD and Total Coliform have been measured in 12 stations selected based on sandstone and aquaculture industries. In this river, there are three sandstone and 4 aquaculture industries that only Salinity and Turbidity were upper of standard value due to agricultural waste while other parameters were placed in the standard range. The result of IRWQI index in each station is 79.2, 77, 77.3, 77.7, 62, 70.7, 73.6, 74.2, 79.2, 77.4, 79.9, 83, respectively that are in good level and is presenting a good purification of this ecosystem, therefore, though the studied industries have effected on water health quality, but, its physical condition such as substrate have moderated the industries’ impacts.

This study was conducted to test the effect of bioremediation the polychaete worm Nereis diversicolor in order to removal of wastewater nutrition derived different densities Huso huso. The aim of this study was determination of different densities for creating the equivalence for rearing of N. diversicolor and H. huso rate in the integrated culture system. Three different densities of H. huso culture with N. diversicolor fed with fish feed waste were considered at water temperature 23°C for 8 weeks. The obtained results demonstrated that N. diversicolor could grow via feeding with the fish waste water. The pure production and survival rate of harvested Nereis in NWF2 treatment was significantly higher than other treatments (P<0.05). The highest removal efficiency of waste water including NO2-N (91%), TSS (89%),  BOD5 (85%),  PO4-P (65%), total phosphorus (63%), total nitrogen (56%), NH3-N (35%), were seen in different treatments. The removal efficiency of waste water nutrition was decreased without use of N. diversicolor. Also, removal efficiency of NO3-N did not occur with presence of the worm. The obtained results demonstrated that increasing of worm growth, decreasing waste water nutrition and achieving of secondary production made system efficiency. The use of worm biomass as a waste treatment method could economically play important role.

The aim of this study was to evaluate the effect of refined poultry slaughterhouse waste water quality on growth performance and body biochemical components. Carp fish with an average weight of 5.59± 0.09 grams were tested in three treatments, each with three replicates for 30 days. Experimental treatments were includes: treatment 1 (100% de-chlorinated tap water), treatment 2 (70% of slaughterhouse waste water+30% de-chlorinated tap water) and treatment 3 (100% of slaughterhouse waste water). The results showed that there was no significant difference at different times in the amount of dissolved oxygen, temperature and pH (p>0.05). So the highest concentration of ammonium and nitrate were 0.222 and 4.160 mg/l in the treatment 2, respectively. There was no significant difference in weight of fish between treatments experiment (p>0.05). The end of experiment, the FCR showed that the only significant differences are there between 2 treatments (1.58±0.15) with other treatments (p< 0.05). Approximate carcasses analysis results showed significant difference in percent of protein, moisture and Ash (p<0.05) although, no significant difference in crude lipids percentage was observed between different treatments (p>0.05). The results showed that poultry slaughterhouse waste con be used for carp culture and for this purpose, it is better to use a mixture of wastewater and fresh water.