Spatial distribution of wind-driven sediment transport rate in a fallow plot in Central Anatolia,Turkey     

Oguzhan Uzun  Sema Kaplan  Selen Deviren Saygın  Feras Youssef  Amin Nouri 《Arid Land Research and Management》2017,31(2):125-139

Wind erosion is a serious land degradation phenomenon in semi-arid parts of Turkey. It is even becoming more critical problem considering the current effects of global warming and climate change in the region. The objectives of this study are to model spatial variation of aeolian sediment transport and to map Sediment Transport Rate (STR) by geostatistics in a fallow plot in the Central Anatolia. STRs for four consecutive wind cases with different vegetation cover rates were determined using the cyclone BEST sediment traps. Plant cover ratio and height changed between 8 and 25% and 3–12?cm throughout the research period, respectively, and soil moistures ranged between 10.9 and 12.7%. The windstorms lasted for 400, 835, 1240, and 50 minutes with the mean wind velocities of 8.6, 7.7, 7.7, and 6.3?m?s^?1, respectively, for cases 1, 2, 3, and 4. The calculated STRs varied between 0.0248?±?0.0170?kg?m^?1?h^?1 and 0.190?±?0.084?kg?m^?1?h^?1. Spatial analysis revealed that the spatial correlations were between 19 and 48?m and different spatial patterns occurred from one case to another. The study results indicated that the amount of transported sediment and its spatial variation were mostly related to velocity and duration of erosive wind in the fallow area of the arid region.  相似文献   

Graphene Oxide/Alginate Quasi-Cryogels for Removal of Methylene Blue     

Gizem Balkız  Evridiki Pingo  Nilay Kahya  Hakan Kaygusuz  F. Bedia Erim 《Water, air, and soil pollution》2018,229(4):131

Quasi-cryogelation technique is a simple yet effective technique for improving the adsorptive efficiency of biopolymer-based adsorbent materials. In this work, a biopolymer-based adsorbent material, graphene oxide alginate quasi-cryogel beads are reported. Alginate biopolymer was crosslinked and frozen at ??21 °C in order to obtain a gel with cryogel-like microstructure. Graphene oxide was included in the bead formulation in order to enhance the adsorptive characteristics. Beads were characterized using Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and swelling experiments. Removal of the model cationic dye, methylene blue, was studied by batch adsorption method. It is found that the adsorption follows the Freundlich isotherm model and pseudo-first order kinetics with reaching an adsorption capacity of 122.26 mg/g in 60 min. Results indicate that the physisorption might be due to the π–π interactions between graphene oxide and methylene blue, in addition to electrostatic interactions. Moreover, quasi-cryogelation technique significantly improved the dye removal properties.  相似文献   

The effects of freshwater rearing on the whole body and muscle tissue fatty acid profile of the European sea bass (<Emphasis Type="Italic">Dicentrarchus labrax</Emphasis>)     

Arzu Özlüer Hunt  Ferbal Özkan  Kenan Engin  Nazmi Tekelioğlu 《Aquaculture International》2011,19(1):51-61

The purpose of this study was to investigate the effect of freshwater rearing on the fatty acid profiles of the whole body and muscle tissue of the European sea bass (Dicentrarchus labrax). Half of initial fish were gradually acclimated to freshwater (FW) kept at the same temperature to salt water and grown in same conditions as their counterparts in saltwater (SW). The decrease in salinity caused an increase in the percentages of 18:1n − 9, 24:1n − 9, 18:3n − 3, 18:2n − 6 and decrease in the percentages of 14:0, 15:0, 20:0, 21:0, 20:5n − 3 and 22:6n − 3 both in the whole body and in the muscle tissue fatty acid profiles. The lipids of FW-reared fish contained significantly (P < 0.01) higher percentages of 18:2n − 6 and 18:3n − 6 than that of SW-reared fish. However, percentages of 20:5n − 3 and 22:6n − 3 fatty acids decreased significantly (P < 0.05) compared with those of salt water-reared European sea bass. There was a clear trend of decrement in the percentages of n − 3 PUFA fatty acids due to the decrease in water salinity. However, the percentages of n − 6 PUFA fatty acids were also increased with the decrease in water salinity. We concluded that the FW acclimation is followed by changes in certain lipid classes of sea bass muscle tissue and whole body samples. n − 3/n − 6 PUFA ratios were characteristic to previously reported ratios for both FW- and SW-reared European sea bass. In addition, EPA/DHA ratios were basically similar for the fish reared in both SW and FW indicating the equal nutritional value of the final products in terms of providing PUFA’s for human nutrition.  相似文献   

Pre‐challenge and post‐challenge haemato‐immunological changes in Oreochromis niloticus (Linnaeus, 1758) fed argan oil against Lactococcus garvieae          下载免费PDF全文

Esin Baba  Ümit Acar  Sevdan Yılmaz  Canan Öntaş  Osman Sabri Kesbiç 《Aquaculture Research》2017,48(8):4563-4572

The present study investigated the effects of argan oil, obtained from Argania spinosa, on pre‐ and post‐challenge immuno‐haematological and biochemical responses of Nile tilapia, Oreochromis niloticus. For this purpose, the fish were fed diets containing 0, 0.5%, 1% or 2% argan oil for 45 days. Following 45 days of feeding, fish were challenged with Lactococcus garvieae and mortality was recorded for 15 days. During the pre‐challenge period, significantly higher respiratory burst activity, total white blood cell (WBC), serum lysozyme activity and myeloperoxidase activity were determined in the argan oil‐fed groups. The serum glucose and cholesterol levels decreased whilst total protein and albumin did not change in the groups fed with argan oil‐supplemented diets. After challenge with Lactococcus garvieae, the percentage survival (%) was found to be the highest in the 1% and 2% argan oil‐supplemented feeding groups. Also, there was a significant increase in weight gain, specific growth rate and feed conversion ratio in those fish fed argan oil. The results of this study indicated that after the supplementation of fish diets with argan oil, especially at 1% and 2% concentrations, the immunological, haematological and biochemical values remained similar in both the pre‐ and post‐challenge periods and the immune response against L. garvieae in Nile tilapia was modulated.  相似文献   

Effect of partial replacement of alfalfa hay with Moringa species leaves on milk yield and composition of Najdi ewes     

Elfadıl E. Babiker  Fahad AL Juhaimi  Kashif Ghafoor  H. E. Mohamed  Khalid A. Abdoun 《Tropical animal health and production》2016,48(7):1427-1433

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Effect of temperature on α-tocopherol, fatty acid profile, and pigments of Diacronema vlkianum (Haptophyceae)     

Y. Durmaz  M. Donato  M. Monteiro  L. Gouveia  M. L. Nunes  T. Gama Pereira  Ş. Gökpınar  N. M. Bandarra 《Aquaculture International》2009,17(4):391-399

Diacronema vlkianum was grown in polyethylene bags at two different temperatures (18 and 26°C) in the laboratory. The biochemical composition level decreased when the temperature increased from 18 to 26°C. The maximum cell number at 18°C was 11.9 × 10⁶ cells ml⁻¹, while maximum cell number at 26°C was 1.6 × 10⁶ cells ml⁻¹. The maximum level of α-tocopherol was 257.7 ± 21.6 μg g⁻¹ dry weight (DW) at 18°C. The highest total carotenoids and chlorophylls were 6.5 mg g⁻¹ DW and 4.3 mg g⁻¹ DW, respectively, and the main pigments were determined as astaxanthin and lutein. Polyunsaturated fatty acids were found to be the predominant group, reaching 39.5% of the total fatty acids at 18°C. This comprised 20:5(n − 3) as the main polyunsaturated fatty acids (20.4%, at 18°C) followed by 22:6(n − 3) (4.8%, at 18°C). The results suggest that D. vlkianum can be successfully used as feed in shellfish hatcheries or aquaculture hatcheries, either as a substitute or in association with other microalgae, when this algae is cultured at 18°C.  相似文献