Influence Of Water Salinity Research Articles

Influence of Water Salinity on Effectiveness of Oil Dispersants

Influence of Water Salinity on Effectiveness of Oil Dispersants

Shrinkage behavior of compacted bentonite considering physicochemical effects

Understanding the shrinkage behavior of bentonite considering physicochemical effects is important to assess the efficiency of buffer barriers in environmental geotechnical engineering. In this paper, shrinkage experiments were conducted on Na-bentonite specimens prepared with salt solutions at various concentrations. NMR and SEM tests were conducted to study the moisture distribution and structural evolution of specimens during the evaporation of water. After sample saturation, the porosity decreases as the pore water salinity increases due to the decreasing swelling deformation with pore water concentration during the saturation process. During drying, the shrinkage deformation of compacted bentonite is anisotropic, with larger axial strains than radial strains. At the fully dried state, the bentonite specimen prepared with distilled water is the densest due to the least crystalline salts in the specimen. At the microscale, as pore water salinity increases, pore water is distributed to smaller pores, and the microstructure is more aggregated. The saline effect on water retention and distribution is weakened as pore water evaporates, originating from physicochemical effects. The structure is also more aggregated after evaporation of pore water. Theoretically, the shrinkage behavior of Na-bentonite considering the influence of water salinity is well described from the perspective of an effective stress-based constitutive relationship.

Influence of Water Salinity on the Efficiency of Fe0-Based Systems for Water Treatment

Metallic iron (Fe0) is a reactive material for treating polluted water. The effect of water salinity on the efficiency of Fe0-based remediation systems is not yet established. This work aims to clarify the reasons why Cl− ions are often reported to improve the efficiency of Fe0/H2O remediation systems. Quiescent batch experiments were carried out to characterize the effect of chloride (Cl−) ions on the efficiency of methylene blue (MB) discoloration in the presence of Fe0. Cl− was used in the form of NaCl at concentrations ranging from 0 to 40 g L−1. The MB concentration was 10 mg L−1, the Fe0 loading was 5 g L−1, and the duration of the experiment varied from 2 to 46 days. Four different Fe0 materials were tested in parallel experiments. Tests with different NaCl levels were performed in parallel with three other organic dyes: Methyl orange (MO), orange II (OII), and reactive red 120 (RR 120). The results clearly show that the presence of Cl− reduces the extent of dye discoloration in all systems investigated. The efficiency of the dyes increased in the order MB < MO < RR 120 < OII. In systems with varying NaCl concentrations, dye discoloration initially decreases with increasing NaCl and slightly increases for [NaCl] > 30 g L−1. However, the extent of dye discoloration for [NaCl] = 40 g L−1 remains much lower than for the system with [NaCl] = 0 g L−1. The results clearly demonstrate that the presence of Cl− fundamentally delays the process of contaminant removal in Fe0/H2O systems, thus improving the understanding of the contaminant interactions in Fe0-based remediation systems. These results also suggest that the effects of other inorganic anions on the efficiency of Fe0/H2O systems should be revisited for the design of field applications.

Interfacial tension reduction of hybrid crude-oil/mutual-solvent systems under the influence of water salinity, temperature and green SiO2/KCl/Xanthan nanocomposites

In order to maximize oil recovery, combined enhanced oil recovery (EOR) methods can be used, which benefit from several mechanisms simultaneously. The application of nanotechnology and mutual solvents were studied separately in recent years. Mutual solvents have the ability to dissolve in both aqueous and oil phases and can show similar performance to surfactants in the water–oil interface. In this study, the effect of ethanol and methyl ethyl ketone solvents with and without a new nanocomposite on the reduction of interfacial tension (IFT) as a mechanism of the main EOR has been examined. The addition of these solvents to nanofluids is a new strategy that enhances the reactions at the interface of the two phases and improves the performance of the IFT mechanism. Also, diluted formation water samples were used as the simplest and most accessible smart water and synergistic effects on the system were investigated. Mutual solvents were tested at 5, 10, and 15 % by volume with and without nanocomposite at 25, 50 and 75 °C. In this way, different parameters of salinity, temperature, different concentrations of solvents and nanocomposite on IFT reduction were investigated. According to the results, each of these processes separately has positive effects in reducing IFT. But the combination of smart water - mutual solvent - nanocomposite showed the best effect in reducing IFT. The addition of solvents to water and nanofluids has a good potential to reduce IFT in reservoirs with high temperature and high salinity conditions. The optimum concentration of nanocomposite in the presence and absence of solvent was 1000 ppm, which shows that the optimum concentration NCs for IFT reduction is not affected by the presence of the solvent. But adding solvent to different concentrations of nanofluid has positive effects in reducing IFT. In general, methyl ethyl ketone has a stronger effect on reducing IFT than ethanol. Finally, the minimum IFT was observed for a mixture of 1000 ppm nanocomposite and 15 % methyl ethyl ketone with 50 % formation water as the base fluid at the temperature of 75 °C.

Feasibility investigation and development of microbial electrochemical biosensors for marine pollution monitoring

Electrochemical biosensor, as a real-time and rapid detection method, has rarely been explored in marine monitoring. In present work, microbial electrochemical biosensors based on two design strategies: disperse system and integrated microbial electrode, were systematically discussed and their feasibility in marine biotoxicity assessment were investigated. An isolation method was initially investigated to eliminate the potential interference and detect the biological response accurately. The influence of water salinity on the current response was eliminated by adopting the salt-tolerant bacteria Staphylococcus aureus as test microorganism and buffer solution with sufficient ionic strength. The biotoxicity of heavy metal ions and pesticides were sensitively determined. Furthermore, a novel integrated microbial biosensor was designed by immobilizing S. aureus with a redox-active gel that consists of chitosan and poly (diallyl dimethyl ammonium chloride) mixture and confined potassium ferricyanide via electrostatic interaction. The IC50 values for Cu2+, Zn2+, Cr2O72− and Ni2+ were 3.01 mg/L, 1.34 mg/L, 7.64 mg/L and 9.41 mg/L, respectively. This work not only verified the feasibility of electrochemical biosensor in marine pollution monitoring, but also compared the pros and cons of two biosensor design strategies, which provide a guidance for the future development and application of marine monitoring devices based on electrochemical method.

The Regulation of Ion Homeostasis, Growth, and Biomass Allocation in Date Palm Ex Vitro Plants Depends on the Level of Water Salinity

The date palm, a central plant in the fragile oasis ecosystem, is considered one of the fruit species most tolerant to salt stress. However, the tolerance mechanisms involved are yet to be addressed and their evaluation until now was mainly based on heterogenous plant material such as seedlings or limited to in vitro experiment conditions. For these reasons, we propose to deepen our knowledge of the morphological and physiological responses to salt stress using acclimated ex vitro plants resulting from the propagation of a single genotype. The plants were irrigated with 0, 150, 300, or 450 mM NaCl solutions for four months. Our results showed that the influence of water salinity on growth and ion-homeostasis regulation was very dependent on stress levels. The 150 mM NaCl concentration was found to improve dry biomass by about 35%, but at higher salt concentrations (300 and 450 mM) it decreased by 40–65%. The shoot:root dry mass ratio decreased significantly at the 150 mM NaCl water concentration and then increased with increasing water salt concentration. The leaf:root ratio for Na+ and Cl− decreased significantly with increasing water salinity up to a concentration of 300 mM NaCl, and then stabilized with similar values for 300 mM and 450 mM NaCl. In contrast to Na+ and Cl−, leaf K+ content was significantly higher in the leaf than in the root for all salt treatments. Unlike Na+ and K+, Cl− was expelled to the surface of leaves in response to increased water salinity. Overall, date palm plants appear to be more capable of excluding Cl− than Na+ and of changing biomass allocation according to salt-stress level, and their leaves and roots both appear to play an important role in this tolerance strategy.

Influence of Water Salinity on the Growth and Survivability of Asp Larvae Leuciscus aspius (Linnaeus, 1758) under Controlled Conditions.

Simple SummarySerious biological imbalances are often caused by poorly thought-out and destructive human activity, but also by progressive climate change. Each of these factors has an enormous impact on the life of terrestrial and aquatic organisms, including fish. As a result of the anthropogenically altered river environment, individual species must migrate from typically fresh to brackish waters that form in river mouths in order to conduct natural life processes such as spawning, as well as in search of food. An excessively high salinity level can be fatal to freshwater finfish, but low salinity can positively affect the growth and survival of larvae, fry and adult fish.The effect of water with a salinity 3, 5, 7, 9 and 11 ppt on the growth and survivability of asp Leuciscus aspius (L.) larvae was investigated. A control sample consisted of asp larvae reared up in freshwater (0 ppt). Larvae were fed for 21 days with nauplii of the brine shrimp Artemia salina. Water salinity was observed to have a considerable effect on the growth and survivability of asp larvae. In addition, saline water extended the life span of Artemia salina nauplii, which resulted in their prolonged availability to asp larvae. Asp larvae showed low tolerance to the salinity of water, reaching 9–11 ppt. Depending on the degree of salinity, the mean final weight of larvae varied from 122.6 to 139.4 mg, at body lengths from 23.8 to 25.6 mm, respectively. The best body length increments were recorded among asp larvae maintained in water with a salinity of 3 ppt. Depending on the level of water salinity, the final survivability of asp larvae ranged from 16.9 to 94.5%. The highest and increasing mortality was demonstrated among the larvae reared in water of the salinity equal to 11 ppt. It is not recommended to rear asp larvae in water with a salinity above 7 ppt due to the low survivability and large differences in the body size of the larvae that managed to survive.

Pore-scale evidence of ion exclusion during methane hydrate growth and evolution of hydrate pore-habit in sandy sediments

Hydrate-bearing sediments constitute complex hydrological systems, within which the pore habit of hydrate significantly affects all physical properties. However, there is scarce pore-scale evidence of the evolution of hydrate growth in porous media and the influence of water salinity in the micro-morphology of hydrate. In this paper, we used X-ray computed micro-tomography (CT) to monitor three experiments of methane hydrate growth in sand partially saturated with either NaBr or KI brine under excess-gas conditions. Gas, brine and hydrate are observed to co-exist at the pore-scale during the evolution of hydrate pore-habit towards three-phase equilibrium. The experiments and data analysis reveal that (1) hydrate forms as a porous medium mixed with inclusions of brine and gas, where hydrate and brine evolve gradually into separate phases as hydrate cages exclude salt ions, (2) hydrate growth mobilizes water over fairly long distances resulting in heterogeneous hydrate distribution, and (3) hydrate can exhibit interconnecting pore-habit at local hydrate saturations higher than ~50%, even if grown under excess-gas conditions. The results imply that hydrate micro-morphology and pore habit evolve during hydrate formation and, we suggest, so do the physical properties of hydrate-bearing sediments. Our findings provide new insights into the micro-morphology of hydrate and evolution of the properties of hydrate-bearing sediments synthesized in the laboratory and in natural systems.

Influence of some ecological factors on the filtration intensity of the oyster (ostrea edulis l.)

The quantitative regularities of filtration of the Black Sea oyster are studied depending on a number of environmental factors. The influence of food concentration on the filtration activity of mollusks is considered. The dependences of the filtration rate on the body weight of oysters for different temperature regimes were determined, and seasonal changes in its intensity in the Kerch Strait and the Donuzlav estuary were characterized. The influence of water salinity on the filtration activity of this type of mollusks has been established.

Influência da salinidade da água na adaptabilidade de ovinos confinados no semiárido brasileiro

Influência da salinidade da água na adaptabilidade de ovinos confinados no semiárido brasileiro

The culture of Nile tilapia at different salinities using a biofloc system

The influence of water salinity on the culture of Nile tilapia with biofloc was evaluated using indicators of water quality, zootechnical performance and animal welfare. Five treatments of different salinities were adopted (0, 4, 8, 12 and 16 g L-1) with three replications. The tilapia were cultured for 90 days and stocked in glass fiber tanks (800 L) at a density of 30 fish m-3 with a mean initial weight of 93.8 ± 0.89 g. Water temperature, chlorophyll-a, sedimentable solids and total suspended solids showed no difference between salinities (p>0.05). The levels of total ammonia nitrogen (3.94 mg L-1) and nitrite nitrogen (0.82 mg L-1) were lower at the salinity of 0 g L-1 compared to the highest salinity (16 g L-1) (p≤0.05). The final weight ranged from 256 to 280 g, with a survival rate of 97 to 100% (p>0.05), which resulted in a productivity of 7.4 to 8.4 kg m-3 (p≤0.05). Glucose was above the baseline value (≤ 60 mg.dL-1) in the 16 gL-1 treatment (76 mg dL-1), and fish growth at the salinities of 8 and 12 g L-1 showed positive allometry (3.020) compared to the other treatments. This demonstrated that it was possible to culture Nile tilapia at salinities of up to 16 g L-1, without compromising performance.

Прогнозирование влияния солености воды на качество измерения обводненности нефти

Прогнозирование влияния солености воды на качество измерения обводненности нефти

Influence of water salinity on genes implicated in somatic growth, lipid metabolism and food intake in Pejerrey (Odontesthes bonariensis).

Pejerrey, Odontesthes bonariensis, is an euryhaline fish of commercial importance in Argentina. This work aimed to determine if water salinity affects the expression of genes involved in somatic growth (gh; ghr-I; ghr-II; igf-I), lipid metabolism (Δ6-desaturase) and food intake (nucb2/nesfatin-1). First, we identified the full-length cDNA sequences of Δ6-desaturase (involved in lipid metabolism) and nesfatin-1 (an anorexigen). Then, pejerrey juveniles were reared during 8weeks in three different water salinity conditions: 2.5g/L (S2.5), 15g/L (S15) and 30g/L (S30) of NaCl. Brain, pituitary, liver and muscle samples were collected in order to analyze mRNA expression. The expression of gh and ghr-II mRNAs increased in the pituitary of fish reared at S2.5 and S30 compared with the S15 group. The expression of ghr-I was higher in the liver of S30 group compared to S2.5 and S15. Igf-I mRNA expression in liver increased with the increment of water salinity, while it decreased in the muscle of S15 and S30 groups. Δ6-desaturase expression increased in S2.5 group compared to S15 in both liver and muscle. S30 caused a decrease in the Δ6-desaturase expression in liver compared to S15. The S30 treatment produced an increase in nucb2/nesfatin-1 mRNA expression in the brain and liver compared to S2.5 and S15. The changes in gene expression observed could help pejerrey perform better during salinity challenges. The S30 condition would likely promote pejerrey somatic growth in the long term.

Sperm quality, and morphology and apoptosis of germinal epithelium cells of ram lambs receiving water of different salinities

The aim of the present study was to evaluate the influence of water salinity on semen quality, and on the morphology and apoptosis of germinal epithelial cells in prepubertal Morada Nova male lambs. Thirty-two lambs were allocated into four treatments with different amounts of sodium chloride (NaCl) added to the drinking water to simulate different water salinities; consequently, the concentrations of total dissolved solids (TDS) were as follows: 640 (control), 3188; 5740 and 8326 mg/L TDS. After 78 days, sperm was collected for analysis. The animals were slaughtered and histological and morphometric analyses and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL) assay were performed on the testis tissue. The thickness of the germinal epithelium and diameter of the seminiferous tubules were measured. A quadratic effect (P < 0.05) was observed in regard to semen volume and sperm abnormalities. There was an increase in the sperm count in the treatment containing 3188 mg/L TDS, compared with the control (640 mg/L TDS); however, this treatment did not differ (P > 0.05) from the other salinity treatments. Moreover, treatments with 3188 mg/L or 5740 mg/L TDS showed a higher (P < 0.05) spermatic vigour than did the other treatments. There was an increase (P < 0.05) in the number of TUNEL-positive cells in the treatment with the highest salinity (8326 mg/L TDS) compared with the control and other treatments. In conclusion, water used for drinking should contain between 3188 and 5740 mg/mL TDS so as to improve the concentration, vigour, motility and volume of semen, and to decrease sperm abnormalities in germinal cells of seminiferous tubule of Morada Nova ram lambs.

Phytoremediation of cadmium by the facultative halophyte plant Bolboschoenus maritimus (L.) Palla, at different salinities.

The cadmium phytoremediation capacity of the halophyte plant Bolboschoenus maritimus (L.) Palla and the influence of water salinity were assessed in a greenhouse experiment, in order to better understand the bioremediation capacity of this plant. Three concentrations of cadmium (0, 50 and 100 μg l(-1)) and four salinity conditions (0, 5, 10 and 20) were chosen to evaluate the cadmium accumulation, in order to test these plants as a potential phytoremediation tool in brackish environments. The cadmium content in water and plants (underground organs, stems and leaves) was analysed with graphite furnace atomic absorption spectrometry. All the plants submitted to salinity 20 and in the three cadmium treatments died. The plants' survival was highest in the lowest salinities, where highest growth and biomasses were also obtained. The plants presented more cadmium content in the rhizomes, followed by stems and even less in leaves. The salt stress of the plants interfered with their cadmium accumulation capacity. The highest cadmium accumulation in the rhizomes occurred at salinity 0, while the salinities 0 and 5 were the most adequate for stems and leaves. The experiment pointed out that B. maritimus represents a good possible intervenient for cadmium bioremediation in freshwater and low salinity brackish water environments, but its use is limited in the habitats of higher salinity.

Influence of water salinity on corrosion risk—the case of the southern Baltic Sea coast

Water corrosivity in Gdansk Bay, Poland, the southern part of the Baltic Sea, was investigated. The analysed region is heavily industrialized, and the coastline is very diverse. Twenty-seven test points along the coastline were selected. Water parameters such as salinity, total dissolved solids content, resistivity, conductivity, oxygenation, pH and corrosion rate were determined. The results of the investigation are presented. Water samples were collected, and structural steel specimens were exposed in the water for 2 months. The corrosion rate for each test point was determined and plotted on a map. The spatial distribution of water parameters was calculated using the ‘inverse distance to a power’ method and presented on the maps. Salinity did not exceed 0.7 %, and average corrosion rate equalled 0.0585 mm/year.

Measurements of assimilable organic carbon (AOC) in high saline conditions using P17

Biofouling caused by the deposition or growth of microorganisms on the membrane surface is one of the major concerns in nanofiltration (NF) and reverse osmosis (RO) processes. Assimilable organic carbon (AOC) has been a useful index to assess the growth potential of bacteria. In the case of drinking water, the AOC assay method has been widely applied to estimate growth or regrowth potential of bacteria in distribution and storage systems. However, studies on AOC measurement for high salinity water samples such as brackish water and seawater are rather scarce. The objective of this research is to investigate the influence of water salinity on the conventional AOC assay method. AOC samples with different salt concentrations were prepared by varying NaCl concentration from 0 to 35,000 mg/L, while the acetate concentration was held at 100 μg/L. The number of cells produced in water samples was measured by the heterotrophic plate count (HPC) method using R2A agar. The result showed that the cell production of Pseudomonas fluorescens strain P17 and Spirillum strain NOX decreased with increasing salinity. Especially, the growth of Spirillum strain NOX was noticeably influenced by water salinity. To further observe the relation between acetate concentration and cell production in high salinity water, organic-free saline water samples were prepared by spiking NaCl in deionized (DI) water. The organic-free saline water samples were enriched with acetate of which concentration was varied to be 0–1,000 μg/L (as acetate). Also, P. fluorescens strain P17 was adjusted to high total dissolved solids (TDS) condition prior to being injected into the saline water samples. The result demonstrated that the amount of microorganisms increased with increasing acetate concentration. Although AOC measurement of saline water using Spirillum strain NOX seemed unacceptable, it was suggested that P. fluorescens strain P17 has the possibility to be used in measuring AOC in saline water. Moreover, the yield factor was altered as a result of reflecting salinity impact as the growth number of P. fluorescens strain P17 was unstable with high saline condition.

물의 염도가 압축벤토나이트의 수리전도도에 미치는 영향

The influence of water salinity on the hydraulic conductivities of compacted bentonite with several dry densities were studied. The hydraulic conductivity increases with increasing salinity only when the dry density of bentonite is relatively low. The degree of increase becomes more remarkable at a lower dry density of bentonite. For bentonite with the density of 1.0 Mg/m{sup 3} and 1.2 Mg/m{sup 3}, the hydraulic conductivity of the 0.4 M NaCl solution increases up to about 7 times and 3 times, respectively higher than that of freshwater. However, for the bentonite with a dry density higher than 1.4 Mg/m{sup 3}, the salinity has an insignificant effect on the hydraulic conductivity, and the hydraulic conductivity is nearly constant within the salinity range of 0.04 to 0.4 M NaCl. The pre-saturation of the bentonite specimen with freshwater has no significant influence on the hydraulic conductivity.

Про вплив деяких екологічних чинників на інтенсивність фільтрації устриці (Ostrea edulis)

Досліджено закономірності живлення фільтрації чорноморської устриці залежно від низки екологічних чинників. Розглянуто вплив концентрації їжі на активність фільтрації молюсків. Визначено залежності швидкості фільтрації від маси тіла устриць за різними температурними режимами та охарактеризовано сезонні зміни її інтенсивності в Керченській протоці та лимані Донузлав. Установлено вплив солоності води на активність фільтрації цього виду молюсків.

Influence of Water Salinity on the Behavior of Some Groups of Organic Substances in the "Bottom Sediments - Water" System

Influence of Water Salinity on the Behavior of Some Groups of Organic Substances in the "Bottom Sediments - Water" System