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With the development of the chemical industry, more and more high-salinity sewage that contains the pollutant phenol. The research in this paper tested Microbial Fuel Cell (MFC) phenol degradation with a focus on the Staphylococcus caprae strain SHBCC D10058 ATCC 35538 as the degrading bacteria. In conditions with a 5% salinity medium and 100mg/L initial phenol concentration, after three days of degradation, 46.25% phenol remained. The phenol concentration was initially 220mg/L; after three days of degradation in a 5% salinity condition, 64.74% phenol remained. 65.93% of phenol remained in the medium with an initial phenol concentration of 300mg/L after three days' degradation. When the Microbial Fuel Cell was utilized with only polycarbonate brine (1.6%salinity, 4.07mg/L phenol), the cell had a maximum power output of 30.070mW/m2, and after three days of degradation, 32.31% phenol remained. [ABSTRACT FROM AUTHOR]

This study was designed to determine the effects of five different salinity levels (25, 30, 35, 40 and 45 ppt) on the survival rate of Farfantepenaeus aztecus larvae from Nauplius5 to post-larvae1 (N5-PL1). For this purpose, 50 larvae that reached the N5 stage were stocked in 2-L round bottom glass flasks in five replications and were grown up to the PL1 stage at 27.6±0.4°C. At the end of the study, as the highest survival (44.00±23.15) in protozoal stages were obtained at 35 ppt salinity levels, the lowest survival 14.00±4.89) were found at 25 ppt salinity levels (P<0.05). The highest survival rates from the M1 stage to the PL1 stage was obtained at 35 ppt (24.40±19.51), 30 ppt (23.20±18.14) and 40 ppt, respectively. The survival rates at 25 and 45 ppt salinity levels were found statistically different from those of 30, 35, and 40 ppt (P<0.05). The results of this study show for the first time that the optimum salinity level is the range of 30-40 ppt for larval culture obtained from the North-eastern Mediterranean population of brown shrimp that is the West Atlantic natural origin. [ABSTRACT FROM AUTHOR]

In the past few years, a water quality testing system has been commonly used in almost every country which is known to have issues related to water contamination. The old system uses the physical inspection of water by taking numerous samples from different water sources. These samples are then verified in the research laboratory using diagnostic technologies. Such techniques are time taking and are not deemed as powerful. Furthermore, new techniques not only inspect the physical qualities of water but also measure the total amount of germs and other infectious items present in the water. Old methods of water testing have drawbacks like complex processing, long result time & low accuracy etc. So, to eradicate all these issues, we must find out an economical and fast way to determine the quality of water. Such a device is called a "Water Salinity Tester (WST)". WST is a device that is used to calculate the amount of Total Dissolved Solids (TDS) in water. The reason for developing this sort of tool is to provide equipment that can help the users to measure the salinity of water so that it can be controlled if the salinity increases to a certain limit. The tool can be used both domestically and industrially. [ABSTRACT FROM AUTHOR]

The capacity of species to tolerate physical stressors is critical in a world of increasing environmental instability, however, past selective environments should dramatically impact on future stress tolerance, particularly in isolated populations. Through stabilising selection, long-term environmental stasis may reduce physiological tolerance, creating an evolutionary legacy where populations are less fit if environments change. Few empirical studies have investigated this evolutionary legacy of past selection, and of particular interest whether stabilising selection in a benign environment reduces stress tolerance in natural systems. Here we use multiple populations of salt-lake invertebrates (Coxiella striata, Austrochiltonia subtenuis) with either stable or fluctuating environmental histories to investigate the relationship between stabilising selection and environmental stress resistance. Tolerance to both salinity and temperature stress were examined in invertebrate populations from lakes with long-term (decadal) stable environments and compared with populations from lakes with extreme salinity variations. Individuals from stable environments demonstrated significantly lower survival under both increasing salinity and temperature stresses when compared with environmentally unstable populations. Our results support the hypothesis that the evolutionary legacy from stabilising selection in constant environments leads to reduced stress tolerance. This finding demonstrates that under an increasingly variable climate, the evolutionary legacies of populations will be critical for future survival and adaptation. [ABSTRACT FROM AUTHOR]

In this paper, two 1D salt intrusion models, i.e. the steady-state and unsteady-state salinity intrusion model are used to assess the salt intrusion distribution in Muthupet estuary, a Ramsar site in Tamil Nadu, India; and Bouregreg estuary, in north-western part of Morocco. Results indicate that the steady-state salt intrusion model performs well to salinity observations especially during post-monsoon period (Indian estuary). Despite the fact that the high-salinity values observed during pre-monsoon period at a distance of 5 km to 7.5 km from the mouth are badly represented by the steady-state model it is a good indicator for the salt intrusion length. Additionally, this research shows that it is likely that an additional source of salt is causing the increase in salinity values at Lagoon reach and that the unsteady-state salt intrusion is able to represent this. On the other hand, a normal estuary is presented in this paper, for study comparison, i.e. Bouregreg estuary. The steady-state salt intrusion model outperformed the model results of the Indian estuary and is better to predict salt intrusion length and salinity variation along the Bouregreg estuary. [ABSTRACT FROM AUTHOR]

The two mangrove species Kandelia obovata and Sonneratia caseolaris were widely planted in the Red River delta. Both K. obovata and S. caseolaris forests play an important role in the economic development and environmental protection of the delta. However, chemical responses of the common mangrove forests to different ecological conditions in the delta have not yet been described. In this study, we evaluated chemical responses of K. obovata and S. caseolaris through comparisons of the content of metabolites and element ions in leaves of mangrove plants located under different ecological conditions in the Red River delta. In the low salinity area (Thuy Truong), specific leaf areas of K. obovata and S. caseolaris were much lower while the succulent index was higher compared to those in the high salinity area (Kim Trung). In Kim Trung, both species had a lower ratio of chlorophyll a/chlorophyll b. K. obvata in lower light (under the S. caseolaris canopy) had lower levels of chlorophyll b, resulting in a higher Chla/chlb ratio. There was no difference in the Mg content of leaves between two areas. An increase in Na content in leaves of mangrove plants in the higher salinity area was evident. The high K/Na ratio in leaves were eveluated for both species in high salinity areas. Our results also showed better uptake of K in leaves of S. caseolaris growing in the low salinity conditions (Thuy Truong), i.e. Thuy Truong has more favourable ecological conditions for S. caseolaris. Carotenoid contents in leaves of both species growing in the higher salinity were lower. [ABSTRACT FROM AUTHOR]

Distributions of a maritime harvestman, Psathyropus tenuipes and a riparian harvestman Paraumbogrella pumilio were investigated along the Sendai River, Tottori City, Honshu, Japan. Psathyropus tenuipes was found from the mouth of the river to the site 4 km upstream where slight salinity (0.1 PPT) was detected in the river. On the other hand, no specimens were found from the upstream sites where no salinity was detected. This indicates that the species needs at least a slight salinity for its occurrence. Paraumbogrella pumilio was found at five sites from the dry riverbed near the Shobu floodgate to a site on the right bank of Sendai River just upstream of Yachiyo Bridge. Occurrence of this species seems to be related to presence of open ground covered with lower grasses on the banks. Recently, the both species were also found from the right bank of the river mouth of Sendai River that is also a part of Tottori Sand Dunes. These are the first records of harvestmen from Tottori Sand Dunes. [ABSTRACT FROM AUTHOR]

Subsurface mooring allows researchers to measure the ocean properties such as water temperature, salinity, and velocity at several depths of the water column for a long period. Traditional subsurface mooring can release data only after recovered, which constrains the usage of the subsurface and deep layer data in the ocean and climate predictions. Recently, we developed a new real-time subsurface mooring (RTSM). Velocity profiles over upper 1 000 m depth and layered data from sensors up to 5 000 m depth can be real-time transmitted to the small surface buoy through underwater acoustic communication and then to the office through Beidou or Iridium satellite. To verify and refine their design and data transmission process, we deployed more than 30 sets of RTSMs in the western Pacific to do a 1-year continuous run during 2016–2018. The continuous running period of RTSM in a 1-year cycle can reach more than 260 days on average, and more than 95% of observed data can be successfully transmitted back to the office. Compared to the widely-used inductive coupling communication, wireless acoustic communication has been shown more applicable to the underwater sensor network with large depth intervals and long transmission distance to the surface. [ABSTRACT FROM AUTHOR]

Salt stress negatively affects germination and seedling growth. Sorghum cultivars (Bohuth70, Inqath and Rabeh), seed soaking in dry yeast extract (3, 6 and 9 g l-1) in addition to dry seeds and electrical conductivity (4, 10 and 16 dS m-1) were studied. Traits of germination ratio at first and final counts, lengths of radicle and plumule, seedling dry weight and seedling vigour index were studied. The cultivar of Bohuth70 and concentration of yeast extract (9 g l-1) were superior at all studied traits, while all traits values were reduced with increased saline stress. The combination (Bohuth70x9x4) was superior to most other treatments at first and final counts, radicle length and seedling dry weight, while superiority of plumule length and seedling vigour index belonged to the combination of (Rabehx9x4). The genetic factor and seed soaking in yeast extract can enhance seed susceptibility to germinate with salt stress or not. [ABSTRACT FROM AUTHOR]

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• A salinity sensor based on fiber Bragg grating is developed. • The water diffusion model of the lamellar polyimide is presented. • After the encapsulation, the sensor can measure salinity and temperature. • The sensor possesses prospects for monitoring the process of seawater intrusion. Under the influence of climate warming, sea level rise and human activities, seawater intrusion has become a significant problem. Seawater intrusion salinates groundwater and impacts on ecological environment and society. It needs to be monitored to scale to environment in order to develop and implement preventive or remedial measures. In-situ large-scale monitoring of groundwater salinity is a key step in the prevention of seawater intrusion. However, current monitoring technologies are either too labor-intensive or excessively expensive when used in large-scale in-situ monitoring. Optical fiber techniques that are presently used in measurements of salinity are mostly limited to laboratory experiments. Herein, a fiber Bragg grating (FBG) salinity sensor for in-situ monitoring of groundwater salinity is proposed. The sensor is composed of a FBG coated with polyimide (PI) and an uncoated FBG for salinity sensing and temperature compensation. On the basis of feasibility test and analyses using water diffusion model, a mathematical matrix for calculating salinity and temperature is proposed and applied to salinity measurement in gravel aquifers. The results indicate that the sensitivity coefficients of FBG coated with lamellar polyimide, to water salinity and temperature, are −0.0358 nm/%, 0.0321 nm/°C, respectively. The uncoated FBG is only sensitive to temperature, and the sensitivity coefficient is 0.0095 nm/%. The results of gravel aquifer measurements show that the FBG salinity sensor has good repeatability and consistency with measurements obtained with an electronic salinity meter. The absolute and RMS errors of the salinity measurements are −0.16 to 0.21%, 0.1048%, respectively, and the absolute and RMS errors of temperature are −0.31 to 0.33 °C, 0.1917 °C, respectively. The FBG salinity sensor provides a new means for in-situ monitoring of seawater intrusion. [ABSTRACT FROM AUTHOR]

Abstract Hydrolyzed polyacrylamide (HPAM) has been widely used in chemically enhanced oil recovery (EOR) processes. However, the sensitivity to salinity limited the utility of HPAM polymers for many potential EOR applications in high-salinity reservoirs. To overcome the HPAM salinity sensitiviy shortcoming, the authors developed anti-salt polymers (ASPs) with high salt-tolerance to be used for mobility-control. ASP is an electrolyte-responsive terpolymer of an acrylamide (AM) with 2-acrylamido-methylpropane-sulphonic acid sodium salt (NaAMPS) and a monomer that is much like N-(4-benzoylphenyl) acrylamide (BPAm). Generally, for reservoirs that have high total dissolved solids (TDS) in water, ASP solutions are projected to generate a high-viscosity injected fluid. However, debates are ongoing as to whether ASP can be successfully applied to low-permeability reservoirs if produced water is used as the polymer mixing water. In this study, produced water taken from block 2 of the Pubei Oilfield development zone in Daqing with a TDS of 12910 mg/L was used to prepare and dilute the polymer aqueous solutions. Comparative experiments with ASPs and HPAM were conducted in regard to their viscosity, stabilities, hydrodynamic radii, and core flooding feasibilities. ASPs had better thickening ability compared with HPAM in produced water. Even with low retention rates, ASP aqueous solutions still held a favorable viscosity after aging for 15 days. Core flooding experiments demonstrated that ASPs has good propagation in porous media and acceptable behavior as a displacing fluid. Improved oil recoveries of 9.54, 13.34, and 15.64% were achieved during the injection of ASP solutions and subsequent water flooding. Furthermore, the result from the pilot test showed that ASP was successfully used in block 2 of the Pubei Oilfield development zone in Daqing, which provides a reference for other oilfields' mobility-control. Highlights • Anti-salt polymer have good thickening behavior when being mixed with produced water. • Anti-salt polymer solution shows acceptable transportation in low-permeability cores. • Anti-salt polymer can significantly improve the oil recovery. • Anti-salt polymer achieved success in pilot test in Pubei development zone in Daqing oil field. [ABSTRACT FROM AUTHOR]

Abstract Sodium chloride (halite) has been traditionally regarded as an unconventional oilfield mineral scale, compared with more prevalent carbonate and sulfate scales. However, with the increasing productions from offshore deepwater and shale gas fields, halite scale occurrence becomes more frequent, leading to significant technical and financial challenges to productions. Although low-salinity water dilution remains the primary approach in controlling halite scale threat, chemical inhibition has been evaluated as an alternative halite control strategy due to the intrinsic issues associated with low-salinity water availability and water quality. There are limited studies concerning the combined effect of metals, especially transition metals with scale inhibitors in halite control. In this study, the combined effect of a number of transition metal ions with two common halite scale inhibitors was evaluated in a laboratory setup. It was found that among the transition metals studied, Pb2+ ion demonstrates a synergistic effect with the scale inhibitors evaluated by considerably extending the halite induction time. The calculated inhibition efficiency also indicates that the presence of Pb2+ improves inhibitor performance. Although Pb2+ is an environmental pollutant, an aqueous Pb2+ concentration of up to 10 mg L−1 can naturally occur in both natural gas produced water and oilfield produced water. The operators can take advantage of the reported synergistic effect of Pb2+ with scale inhibitors in this study while designing field halite control strategy. The enhanced inhibition efficiency elaborated in this study can be useful in designing the halite scale control strategy, if a decent amount of Pb2+ is present in the produced water. Graphical abstract Image 1 Highlights • Combined effect of transition metals with halite inhibitors was evaluated. • FCN is superior than PAA with a prolonged halite induction time. • Pb2+ ion demonstrates a synergistic effect with both FCN and PAA inhibitors. • Calculated inhibition efficiency is the highest for Pb2+ with FCN inhibitor. [ABSTRACT FROM AUTHOR]

Abstract Enhanced oil recovery by low-salinity waterflooding (LSW) has been shown to result from the combined effect of various physical mechanisms. In this study, laboratory experiments were designed in such a way that only fines migration mechanism remains active. Then, experimental observations and detailed characterizations of core plugs and produced fluids (water and oil) were used to analyze the effect of fines migration-induced formation damage on displacement efficiency. In the first set of experiments, core plugs of Berea and Obernkirchener sandstones were subjected to single-phase injections of water at salinities 40, 30, 20, 10, 5, 2.5, 0.5 and 0 g/L NaCl. An order-of-magnitude decrease in permeability was observed for both core plugs and was associated with an increase in fines concentration in the produced water. SEM-EDS images of the produced fines showed that kaolinite is mobilized as the salinity is reduced. SEM images of the pores before and after injection also showed fines retention and blockage. In the second set of experiments, two-phase LSW was performed on a pair of core plugs comparable to those in the first set of experiments. Kaolinite migration results were consistent with those of single-phase LSW. The two-phase LSW experiments showed 50% reduction in water relative permeability and 3% increase in oil recovery. Because no wettability alteration mechanism was active, the increase in oil recovery is attributed solely to enhanced displacement due to fines migration. Highlights • Laboratory experiments are performed on Berea (300 mDarcy) and Obernkirchener (3 mDarcy) core samples. • SEM-EDS analysis of the produced fines show production of kaolinite and quartz fines. • Permeability damage is associated with the production of kaolinite fines. • Higher recovery is observed after low-salinity waterflooding in both high-permeability and low-permeability core samples. [ABSTRACT FROM AUTHOR]

Abstract Irrigation water salinity effects on oregano growth, water use, yield and quality parameters were investigated. For this aim, eight irrigation water salinity levels including 0.54 (control), 1.2, 1.8, 2.5, 3.5, 5.0, 7.0 and 10 dS/m were utilized. The plants in all of 7 and 10 dS/m and two out of five replications of 5 dS/m treatment could not survive until the end of the experiment. The mean soil salinity and seasonal averaged drainage water salinity values increased with increasing salinities of applied irrigation water. Compared to control 27, 33, 44 and 74% reductions in total dry yields, and 27, 38, 49, and 77% decreases in dry leaf yields were calculated for 1.8, 2.5, 3.5 and 5 dS/m treatments, respectively. In general, increased irrigation water salinity caused increases in total phenolic content, total flavonoid content, extract yield which shows the amount of water extractable matter from the plants and antioxidant activity whereas significant decreases in total oil content. Among the essential oil components, carvacrol, β-cymene and γ-terpinene contents decreased with increasing water salinities up to 2.5 dS/m and after this level sharply increased but linalool content showed a reversed pattern. A threshold value of 0.50 dS/m was calculated for total fresh yield of oregano but it was not possible to determine a threshold salinity value for total dry yield, dry leaf yield and total oil content. Based on these results, oregano is a very sensitive plant to salinity. [ABSTRACT FROM AUTHOR]

Abstract To examine how the rates and pathways of anaerobic organic carbon mineralization (AOCM) of tidal freshwater wetlands change with low-level increases in salinity, we investigated the rates and controls of microbial iron and sulfate reduction, methane production, and total AOCM in tidal wetlands along a freshwater to oligohaline (0.1–3.3 ppt) gradient in the Min River Estuary in southeastern China. Porewater chloride was found to be strongly correlated with total organic carbon (TOC), carbon to nitrogen (C:N) ratios, and porewater geochemistry (sulfate, pH, ammonium, and dissolved methane levels). Furthermore, a higher plant biomass, larger iron oxides pool, and lower sulfide levels were observed in the oligohaline wetlands. The contribution of microbial sulfate reduction to AOCM increased from 16% to 67%. In contrast, the contribution of microbial iron reduction and methane production declined from 52% to 22% and 12% to 2%, respectively, along the increasing salinity gradient. No consistent changes were found in the total AOCM rates. The rates of methane production were primarily controlled by the C:N ratios and concentrations of porewater ammonium and amorphous iron oxides, while the microbial sulfate and iron reduction rates were mainly controlled by belowground biomass, water content, and concentrations of porewater chloride and sulfate. Our findings provide insight into the potential consequences of modest saltwater intrusion; these may not alter the rates of AOCM in the Min River Estuary, but could change the dominant AOCM pathway from microbial iron reduction to sulfate reduction and accelerate sulfidic effects in this historically freshwater wetland ecosystem. Graphical abstract Unlabelled Image Highlights • The rates of total anaerobic organic matter mineralization are tolerant to a low-level increase in salinity. • The anaerobic organic matter mineralization pathway is sensitive to minor salinity changes. • Salinity are responsible for the decline in microbial iron reduction, suppression of methane production, and enhancement of sulfate reduction. [ABSTRACT FROM AUTHOR]

Highlights • Low salinity (0–2%) had negligible influence on the SNAP process. • The SNAP process could treat 3% salinity wastewater by enhanced aeration. • As low as 0.5% salinity had severe suppression on NOB activity. • The enhanced aeration could selectively stand out the AOB and anammox activities. • The AOB could produce more ammonia monooxygenase to fight against the salinity. Abstract In this study, acclimation of freshwater nitritation-anammox sludge to remove nitrogen in high saline and hypersaline wastewater was evaluated, during which the microbes activity and microbial community revolution were revealed to understand the fate of a nitritation-anammox process (SNAP) in response to increasing salt stress. By enhanced aeration, the SNAP system can treat saline (3%) ammonium-rich (185 mg/L) wastewater after gradual adaption. Hypersalinity (5%) caused final deterioration of the SNAP system due to a severe inhibition on anammox activity. Genera Kuenenia (anammox), Nitrosomonas (AOB) and Nitrosovibrio (AOB) bacteria were salt adaptable microbes, while genus Nitrospira (NOB) bacteria were sensitive to salinity. Under the enhanced aeration, AOB bacteria could bear 3% salinity with possible enriched ammonia monooxygenase to stimulate the conversion of ammonium to nitrite by producing more intermediate-hydroxylamine, which could alleviate the negative effect of insufficient hydroxylamine oxidase members in AOB bacteria. [ABSTRACT FROM AUTHOR]

Abstract Detailed sedimentological and ichnological analysis of core material from selected wells were performed in order to fully characterize the range of facies encountered within Cenomanian formations of Ivorian offshore basin. Results indicate that the cored successions comprise four major groups of lithofacies: Pebbly (CS, PS) , clean sandstone (S) , muddy sandstone (S*M) and mudstone (HM, ML, MJ & M). These lithofacies groups were further sub-divided into component facies based mainly on sedimentary structures. The pebbly group comprises conglomerate sandy and pebbly sandstone. The clean sandstone group includes seven facies: massive sandstone, laminated sandstone, cross-bedded sandstone, bioturbated sandstone, deformed sandstone, wavy-bedded sandstone and rippled sandstone. The muddy sandstone group comprises bioturbated muddy sandstone, while the mudstone group comprises four main facies, namely wavy-bedded heterolithic/sandy mudstone, calcareous mudstone, silty mudstone and pure mudstone. A range of ichnofossils were identified in the cores including: Planolites isp, Palaeophycus isp, Lockeia isp, Phycosiphon isp, Thalassinoides isp, Rhizocorallium isp, Cylindrichnus isp, Chondrites isp and Teichichnus isp. Among these, the Phycosiphon isp Chondrites isp and Rhizocorallium isp reveal fully marine salinities in some intervals of these cores, although Chondrites isp usually used as proxy for disoxia and Rhizocorallium isp were sometimes associated with Glossifungites isp ichnofossils. Integration of the sedimentary data (lithofacies) and trace fossil ichnofossils data revealed several depositional environments ranging from coastal/deltaic to shallow marine settings within the Cenomanian cores. Highlights • Four lithofacies: Pebbly, sandstone, muddy sandstone, mudstone. • Main sedimentary structures: structureless, lamination, ripple, cross and wavy- bedded. • Main trace fossils: Rhizocorrallium isp , Chondrites isp , Planolites isp , Thalassinoides isp , Teichichnus isp , Palaeophycus isp., Lockeia isp, Phycosiphon isp, Cylindrichnus isp. • Phycosiphon isp Chondrites isp , Rhizocorallium isp reveal fully marine salinities. • Several depositional environments ranging from coastal/deltaic to shallow marine settings. [ABSTRACT FROM AUTHOR]

Previous short-duration depuration studies with the eastern oyster (Crassostrea virginica) demonstrated difficulty in achieving significant naturally incurred Vibrio vulnificus population count reductions. The present study used long-duration depuration (14 days) at controlled temperatures (10 or 22°C) and salinities (12, 16, or 20 mg/g). All depuration temperature–salinity combinations significantly reduced V. vulnificus counts, with greatest reductions seen in 12 mg/g, 10°C seawater (2.7-log CFU/g reduction) and in 20 mg/g, 22°C seawater (2.8-log reduction). Mesophilic vibrios dominated the overall microflora of freshly harvested oysters, whereas refrigerated storage selected for psychrotrophic bacteria (Pseudomonas spp., Aeromonas spp., Shewanella spp., Psychrobacter spp.) as well as did depuration at 10°C (Pseudoalteromonas spp., Shewanella spp., Vibrio spp.). Depuration at 22°C retained dominance of mesophilic vibrios, including pathogenic species, followed by Shewanella spp., Pseudoalteromonas spp., and Photobacterium spp. Although aerobic plate counts were lower in 22°C depurated oysters (5.0 log versus 6.0 log) compared with 10°C, depuration at 10°C offered greater V. vulnificus population reductions than depuration at 22°C. This advantage was only seen at 12 mg/g salinity, with no impact at 16 and 20 mg/g salinities. No depuration treatment reduced V. vulnificus counts to nondetectable levels. Use of prolonged depuration may be a helpful intervention to control V. vulnificus populations in oysters. [ABSTRACT FROM AUTHOR]

Abstract The estuaries are characterized by the formation of salinity gradients and are frequently associated with anthropic activities. Studies that show the condition of organisms against the natural environmental variations are fundamental for future evaluation of environmental change due to anthropic impacts. Biomarkers are useful tools defined as biological changes in low levels of organization induced by stressors and considered as predictive responses of more severe effects. The aim of this study was to characterize the modulation of biochemical biomarkers in Ucides cordatus against the natural variation a pristine mangrove forest in an Amazonic estuary (Japerica Bay). The samplings were carried out throughout one year at rainy-dry transitional period (June/2013), dry period (September/ 2013), dry-rainy transitional period (November/ 2013) and rainy period (February/ 2014) in the lower, middle and upper estuary. The biochemical biomarkers evaluated were glutathione-S-transferase (GST), glutamate cysteine-ligase (GCL), total antioxidant capacity (ACAP), reduced glutathione (GSH) concentration and the lipid peroxidation (LPO). There was a decrease in the activity of both enzymes, GSH concentration and lower LPO in the rainy-dry transitional period for the organisms of all sites, pointing to this period as a season of greater metabolic stability. The organisms, especially those of the middle estuary, presented physiological plasticity against the variations of the environment which they are submitted. Seasonality, more than salinity influence due to position in estuary, is the main modulator of biomarkers. Also, our results indicate that the species presents high viability for biomonitoring studies. Highlights • Biochemical biomarkers in U. cordatus from a pristine mangrove forest in an Amazonic estuary was seasonally characterized. • Antioxidant defenses and the lipid peroxidation (LPO) were determined in crabs from lower, middle and upper estuary. • The organisms presented physiological plasticity against the environmental variations that they are submitted. • Seasonality is the main modulator of analyzed biomarkers. • U. cordatus presents a high viability as a sentinel species for biomonitoring studies. [ABSTRACT FROM AUTHOR]

Abstract Sufficient swelling pressure of compacted bentonite upon wetting is necessary to provide long-term stability to an engineered barrier system under conditions of thermal gradient and variable water chemistry in a high-level radioactive waste repository. To investigate the combined thermal and saline effects on the swelling pressure of Gaomiaozi (GMZ) bentonite, constant-volume swelling pressure tests were performed on densely compacted specimens inundated with deionized water, NaCl, and CaCl 2 solutions at 20 °C and 60 °C. The results indicate that high temperature and saline solutions decrease the swelling pressure. Crystalline swelling dominates the constant-volume swelling of densely compacted bentonite. For a given cation type, a higher temperature or higher solution concentration resulted in a lower swelling pressure. The decreasing surface potential and increasing osmotic suction with solution concentration both weaken the clay swelling. The effects of temperature on the swelling pressure are explained by the role of the lattice contraction. The degeneration of the interlamellar adsorbed water at high temperature weakens the crystalline swelling. The effects of cation types are interpreted by their difference in chemical activity. Ca2+ ions possess higher exchange capacity and larger hydrated radius than those of the Na+ ions. When densely compacted Na-bentonite is wetted with CaCl 2 solution, the possible change of the interlamellar cations from Na+ to Ca2+ ions would promote the crystalline swelling. The osmotic suction imposed by CaCl 2 solution may offset the role of the cation exchange to a small extent. The effect of temperature on the swelling pressure exceeds that of the cation types. For a given solution concentration, the specimen wetted with NaCl solution developed lower swelling pressure than that with CaCl 2 solution at 20 °C, whereas the opposite tendency appeared at 60 °C. In addition, specimens saturated with deionized water and NaCl solution at 20 °C obtained insignificant difference in pore size distribution, whereas identifiable differences in pore size distribution occured at 60 °C. The combined thermal and saline effects on the swelling pressure may be explained by the role of the lattice contraction at varied clay structure. When CaCl 2 solution is used, the quasicrystals contain more montmorillonite layers than the case of the NaCl solution. The role of the lattice contraction at high temperature is expected to decrease the swelling pressure to a greater degree in the case of the CaCl 2 solution. The remarkable increase in the osmotic suction at high temperature and high solution concentration could also enlarge the decrease in the swelling pressure. These conjectures, however, still require quantitative interpretations via microscopic tests such as X-ray powder diffraction tests on bulk samples. Highlights • High temperature preferentially dominates crystalline swelling. • High temperature has greater effects on PSD. [ABSTRACT FROM AUTHOR]

Abstract The framework of the intrinsic compression behaviour of normally consolidated soft clay proposed by Burland (1990) is widely adopted in engineering practices. However, further investigations should be conducted on its validity in the coastal and offshore environments to verify the effect of pore water salinity. In the present work, oedometer tests were performed on remoulded artificial soft clays (mixtures of kaolin and bentonite with 0%, 5%, 10%, and 20% of bentonite by mass). The artificial clays were salinized with sodium chloride solutions at concentrations 0 mol/L (distilled water), 0.17 mol/L, 0.51 mol/L, 0.86 mol/L, and 1.70 mol/L at water contents equal to 1.0–1.5 times of the liquid limits. The results showed that the 'intrinsic' properties of clays, including the compression index C c ⁎(100–1000 kPa), void ratio e 100 *, and compression line based on the void index I v , changed with the pore water salinity. Following the empirical correlation proposed by previous researchers, the decrease in C c ⁎ caused by pore water salinity could be generally characterised by the liquid limit and void ratio at the liquid limit (e L). The dispersed correlation between the predicted e 100 ⁎ and the experimental results in this study were caused by the significant changes in e 0 / e L controlled by pore water salinity. The relationships between void index I v and vertical stress σ v ' deviated from the intrinsic compression line (ICL) under the saline environment. For the artificial clay rich in smectite, the slopes of I v –log σ v ' before yielding increased with pore water salinity at the initial water content. Pore water salinity affected the intrinsic compression behaviour of soft clays primarily composed of kaolinite to a lesser extent. Highlights • The pore water salinity changes e 100 ⁎. • Normalised compression curve deviates from Burland's intrinsic compression line at small stress. • Burland's framework needs to be updated considering salinity effect and small stress. • The particle flocculation alters the intrinsic compression behaviour of remoulded soft clays. [ABSTRACT FROM AUTHOR]

Double diffusion convection, driven by two constituents of the fluid with different molecular diffusivity, is widely applied in oceanography and large number of other fields like astrophysics, geology, chemistry and metallurgy. In case of ocean, heat (T) and salinity (S) are the two components with varying diffusivity, where heat diffuses hundred times faster than salt. Component (T) stabilizes the system whereas components (S) destabilizes the system with overall density remains stable and forms the rising and sinking fingers known as salt fingers. Recent observations suggest that salt finger characteristics such as growth rates, wavenumber, and fluxes are strongly depending on the Rayleigh numbers as major driving force. In this paper, we corroborate this observation with the help of experiments, numerical simulations and linear theory. An eigenvalue expression for growth rate is derived from the linearized governing equations with explicit dependence on Rayleigh numbers, density stability ratio, Prandtl number and diffusivity ratio. Expressions for fastest growing fingers are also derived as a function various non-dimensional parameter. The predicted results corroborate well with the data reported from the field measurements, experiments and numerical simulations. [ABSTRACT FROM AUTHOR]

Spring water is a reliable source of potable water in many parts of the world. Uplifted coasts of the Southern Kerala host many high yielding cold water springs which emerge from the sand - clay interface of the Neogene outcrops. Lack of adequate studies on the hydrological and water quality aspects of these springs is challenging the wise use and management of these springs. Therefore, an attempt has been made to map the locations and study the water quality of the free-falling type of springs emerging from the Neogene outcrops exposed on the cliffed coasts of Southern Kerala, especially falling within the jurisdiction of Kollam and Thiruvananthapuram districts. A total of 31 springs from four distinct geomorphic settings has been located in our survey conducted in 2008-2009 period. But, our recent survey carried out in March 2017 revealed that about 10 % of the springs were dried out due to various reasons. The total spring water discharge during 2017 was about 450 liters/minute against the total discharge of 800 liters/minute in 2007-08 period. In general, the hydrochemistry of spring waters is dominated by alkali and strong acids, i.e. alkali-chloride type. Most of the hydrochemical parameters exhibit a great degree of seasonal and spatial variations and are well within the permissible limits (with the exception of pH) for all four groups of springs. The low mineral contents may be attributed to minimal weathering from silicate-rich rocks and insignificant leaching from soil due to infiltration from anthropogenic activities. The spring water quality in all the four groups of the study area is bacteriologically contaminated and therefore proper disinfection is required before human consumption. Most of the spring water samples are classified to be “excellent to good” for irrigation and is not expected to cause any salinity hazard. [ABSTRACT FROM AUTHOR]

Nitric oxide (NO) is a short-lived compound of the marine nitrogen cycle; however, our knowledge about its oceanic distribution and pathways is rudimentary. Here we present the measurements of dissolved NO in the surface and bottom layers at 75 stations in the Bohai Sea (BS) and Yellow Sea (YS) in June 2011. Moreover, NO photoproduction rates were determined at 27 stations in both seas. The NO concentrations in the surface and bottom layers were highly variable and ranged from below the detection limit (i.e. 32pmolL−1) to 616pmolL−1 in the surface layer and to 482pmolL−1 in the bottom layer. There was no significant difference between the mean NO concentrations in the surface (186±108pmolL−1) and bottom (174±123pmolL−1) layers. A decreasing trend of NO bottom layer concentrations salinity indicates a NO input by submarine groundwater discharge. NO in the surface layer was supersaturated at all stations during both day and night and therefore the BS and YS were a persistent source of NO to the atmosphere at the time of our measurements. The accumulation of NO during daytime was resulting from photochemical production and photoprodcution rates were correlated to illuminance. The persistent nighttime NO supersaturation pointed to a, so far unknown, NO dark production. NO sea-to-air flux densities were much lower than the NO photoproduction rates. Therefore, we conclude that the bulk of the NO produced in the mixed layer was rapidly consumed before its release to the atmosphere. Overall, the oceanic NO emissions to the atmosphere were negligible compared to anthropogenic NOx sources such as emissions from ships. [ABSTRACT FROM AUTHOR]

The mineral rock salts present in the Mahai Salt Lake of the Qaidam basin exhibit high solubilities in water. In addition, the multicomponent underground brine exhibits a high salinity and is easily precipitated. In the natural state, brine transport in the brine layer is extremely slow, and the brine is in a relatively stable chemical equilibrium state with the rock salt media. However, during mining, both the seepage and the chemical fields fluctuate significantly, thereby disrupting the equilibrium and leading to variations in the chemical composition and dynamic characteristics of the brine. Therefore, we selected underground brine from the Mahai Salt Lake, collecting a total of 183 brine samples over three stages of mining (i.e., the early stage of underground brine extraction, the initial stage of mining, and the later stage of mining). Using a range of analytical techniques, the chemical dynamics of the underground brine water and its evolution were systematically studied. We found that evaporation and enrichment were the main mechanisms of underground brine evolution in the Mahai Salt Lake, with cation exchange and mineral dissolution/precipitation being key factors in determining the dynamic characteristics and evolution of the brine. [ABSTRACT FROM AUTHOR]

In order to better understand the influence of changing salinity conditions on the trophic transfer of 137 Cs in marine fish that live in dynamic coastal environments, its depuration kinetics was investigated in controlled aquaria. The juvenile turbot Scophthalmus maximus was acclimated to three distinct salinity conditions (10, 25 and 38) and then single-fed with compounded pellets that were radiolabelled with 137 Cs. At the end of a 21-d depuration period, assimilation efficiencies (i.e. AEs = proportion of 137 Cs ingested that is actually assimilated by turbots) were determined from observational data acquired over the three weeks. Our results showed that AEs of 137 Cs in the turbots acclimated to the highest salinity condition were significantly lower than for the other conditions (p < 0.05). Osmoregulation likely explains the decreasing AE observed at the highest salinity condition. Indeed, observations indicate that fish depurate ingested 137 Cs at a higher rate when they increase ion excretion, needed to counterbalance the elevated salinity. Such data confirm that ambient salinity plays an important role in trophic transfer of 137 Cs in some fish species. Implications for such findings extend to seafood safety and climate change impact studies, where the salinity of coastal waters may shift in future years in response to changing weather patterns. [ABSTRACT FROM AUTHOR]

Mangrove forests and adjacent creeks are known to be highly productive estuaries, which are partly supported by benthic microalgae that grow on the sediments. During surveys investigating the microalgal floras of mangrove swamps in the eastern part of Java Island, a mud sample unexpectedly included large numbers of a notorious fish killer, Chattonella-like motile cells, and its resting cysts. These motile cells were established as clonal cultures for further identification and physiological tests. The cysts were examined through palynological and molecular biological means. Identification based on light microscopy and ribosomal RNA gene sequences confirmed that these cells and cysts were Chattonella marina var. marina. While the strains were genetically identical to the temperate strains isolated from Japan and China, temperature experiments showed that the Indonesian strains possessed a high maximum quantum yield of photosystem II even after exposure to 34 °C, a temperature at which the Japanese strain could not survive. Salinity experiments showed adaptation of the strains to a salinity of 15. These findings, together with the discovery of populations of cysts in the mangrove sediment, highlight the tough and unique nature of the Indonesian strains, which are likely adapted to wide fluctuations of temperature and salinity in mangrove swamps, and pose a potential risk to fisheries in Indonesia. [ABSTRACT FROM AUTHOR]

To better understand the factors that influence seafloor serpentinite mudflows, such as those recently documented on the Marianas seamounts, we have conducted rheological measurements on composite serpentine-brucite suspensions at 7 °C and a salt concentration of 0.6 M. The resulting flow curves were fitted by the Bingham fluid model, from which the Bingham yield stress and plastic viscosity of each suspension was determined. Both the yield stress and plastic viscosity increase as the water content of the suspension decreases. Increasing the brucite fraction in the solid mixture results in an increase in yield stress and a decrease in viscosity of the suspension for the same water/solid ratio. Physicochemical parameters such as pH, temperature and electrolyte concentration also moderately affect the rheology of the suspension, but the influence is not as significant as has been previously observed for suspensions containing smectite. The results suggest that mineral composition of the serpentinite mud, especially the abundance of brucite, has as much of an impact as water content on variable mudflow behaviors such as those observed at the Mariana seamounts. [ABSTRACT FROM AUTHOR]

The Northern South China Sea (NSCS) is one of the most important marginal seas in the northwest Pacific Ocean. It receives large amounts of terrestrial inputs, and is affected by intrusion of Kuroshio Water. Dissolved manganese (Mn) can be used as a chemical tracer, facilitating study of fluxes and processes at ocean interfaces. To investigate the behavior and transport of dissolved Mn in the NSCS, we measured the concentrations of dissolved Mn in samples collected in summer 2011 and 2015, during field survey voyages supported by the National Science Foundation of China. The concentration of dissolved Mn ranged from 0.5 to 29.9 nM, with an average of 3.7 nM. Elevated concentrations (>15 nM) of dissolved Mn were found in coastal waters, while low concentrations (<3 nM) were found in areas affected by Kuroshio Water intrusion. There was no significant inter-annual variation in the dissolved Mn concentrations in the study region. Vertical profiles of dissolved Mn in the NSCS were similar to those found in open ocean conditions, with maxima occurring in surface waters and a decrease with depth. Large inputs of dissolved Mn occurred from terrestrial sources to the NSCS coastal areas via the Pearl River. Variations in the distribution of dissolved Mn resulting from intrusion of Kuroshio Water and its interactions with NSCS water were associated with Shelf Water transport. Data on dissolved Mn concentrations across the NSCS slope indicated that the offshore transport of Shelf Water in the upper water layer plays an important role in regulating the distribution of dissolved Mn. A preliminary box model was established to develop a dissolved Mn budget for the NSCS. The flux of dissolved Mn was dominated by exchanges between the NSCS and the northwest Pacific Ocean, with >60% of the material transport flux occurring in the Luzon Strait. [ABSTRACT FROM AUTHOR]

In this study we apply hyperspectral imagery to identify saline blank patterns within the mixed mangrove forest of Sunderban Bio-geographic Province, West Bengal, India. We use derivative analysis to identify hyperspectral wavelengths that are sensitive to the presence of minerals comprising saline blanks. These wavelengths have been considered for development of a novel saline blank identification model. The wavelength showing derivative value with maximum absorption in the SWIR region at 1780 nm and maximum reflection in the red region at 690 nm has been extracted for development of saline blank index. This index has been compared with the existing salinity indices and a detailed analysis has been carried out. It is found that the index outperforms existing salinity indices – normalized differential salinity index and salinity index, and accurately detects the saline blank areas of Henry Island of the Sunderbans Delta. The accuracy of pixels identified as saline blank pixels has been assessed by comparing the overall accuracy with other existing indices. Physical sampling has also been carried out and the salinity results have been compared with the image-derived results. [ABSTRACT FROM AUTHOR]

Compost salinity is an ongoing concern for compost producers, especially with certain feedstocks and in arid or semiarid regions. Current testing protocols call for sampling and testing ex-situ via 1:5 (w/v) slurries via electrical conductance. For this research an alternate approach has been proposed, the use of portable X-ray fluorescence (PXRF) spectrometry. Adapting methods developed for soil and water salinity analysis via PXRF, elemental data was used as a proxy for the prediction of compost salinity. In total, 74 compost samples were scanned with PXRF followed by traditional laboratory analysis. Results indicated a strong correlation between the datasets (R 2 0.80; RMSE 1.04 dS m −1 ), similar to findings for soil and water salinity. Furthermore, using the same elemental dataset, compost pH was reasonably predicted (R 2 0.63; RMSE 0.35). PXRF has the benefit of being able to be conducted in-situ or in the laboratory. And, multiple chemical parameters of interest can potentially be predicted from the same dataset. In conclusion, PXRF shows promise for rapid, in-situ salinity determination of composted products. [ABSTRACT FROM AUTHOR]

The moderately halophilic bacterium, Virgibacillus halodenitrificans PDB-F2, is able to degrade phenol in high-salinity environment, which copes with external salinity fluctuation by biosynthesis or uptake of compatible solutes. Four putative compatible solutes transport systems BetL, OpuD1, OpuD2 and OpuD3, which belong to betaine-carnitine-choline transporters (BCCT) family, have been predicted from the complete genome sequence of V. halodenitrificans PDB-F2. This study investigated the responses of four transport genes betL , opuD1 , opuD2 and opuD3 to NaCl stress in V. halodenitrificans PDB-F2. Transcriptional analysis showed that betL , opuD1 , opuD2 and opuD3 were induced by NaCl stress, and had specificity for glycine betaine (GB). The maximal induction of four transport genes transcription depended on high salinity plus GB. Exogenous GB afforded effective osmoprotection for V. halodenitrificans PDB-F2 at high salinity, especially at 15% (wt/vol) NaCl. Escherichia coli MHK13 is a mutant strain which is unable to grow at high salt condition. We examined the growth of E. coli MHK13 complemented with each of four transport genes and examined the uptake of GB in cells by 1 H nuclear magnetic resonance ( 1 H NMR) spectroscopy under high salt condition. These data showed that all four transporters were able to transport GB. [ABSTRACT FROM AUTHOR]

This paper shows the important role that circulation can play in the long-term variability of thermohaline properties of the bottom layer in the Irminger Sea, and the increase in salinity in the 21st century in spite of intense ice melting in the Arctic and freshening of the upper and intermediate layers that started over the last 5-7 years in the North Atlantic. [ABSTRACT FROM AUTHOR]

Glass objects are common in shipwrecks since they are associated with ordinary glassware or commercial products. The alteration pathologies of historical glasses from two wrecks from the Mediterranean Sea were analyzed to characterize their alteration mechanisms. The results of this research proved that the alteration layers presented a moderate content of Na 2 O, similar to the average salinity of the ocean, and a high content of Al 2 O 3 due to an extremely basic environment during the corrosion process. The biofouling layer protected the glass surfaces. Dark deposits with a high content of MnO were observed in the most instable glass. [ABSTRACT FROM AUTHOR]

Impact of four major cyclones: Phailin, Helen, Lehar, and Madi have been studied in terms of changes in ocean productivity utilizing Indian satellite Oceansat-2 ocean color monitor and MODIS-Aqua data during October-December 2013. The 8-day and monthly composite chlorophyll images have been generated owing to the pre-, during, and post-stages of four cyclones; out of which, three were very severe cyclonic storms and the Helen was severe cyclonic storm. The chlorophyll concentration increased two- to threefolds due to the aftereffect of cyclone in the coastal water, and the concentration was very high (around 2-3 mg/m3). To understand the possible links of cyclones to cooling and upwelling, MODIS-Aqua sea surface temperature (SST) images have been processed. The SST images have shown the cooling effect near the cyclone track pass, over Bay of Bengal. The cooling was observed by 2-3 degree Celsius during the above cyclones. To understand the in situ surface water and water column salinity and temperature variability, the Argo float data are plotted and interpreted. The surface contour shows the lowering of salinity and temperature with effects of cyclones. In addition, the Argo depth profile data have shown possible mixed layer deepening in few profiles around halocline and thermocline depths. This study will be useful for mapping potential fishing zone, ocean biogeochemistry and other useful applications and research. [ABSTRACT FROM AUTHOR]

The aim of this study is to compared with amounts in per gram and the egg diameters, hatching rates in 25 °C and 30 ° temperatures and 25‰, 030‰, 035‰ salinity of Artemia sp. from four different origins (California, China, Utah and Vietnam). Egg count and diameter measurement was carried out with the use of binocular microscope. The most number of eggs in 1 gram was determined to be from Utah originated Artemia sp. while the least was determined to be from California originated ones. Hatching rates were detected to be the highest at 30°C temperature, 25‰ salinity, at the 18th hour in Vietnam originated Artemia sp. In conclusion, it was detected that the hatching time for Artemia sp. varies depending on the temperature and salinity of the water. [ABSTRACT FROM AUTHOR]

In this experiment, the responses of plant growth, gas exchange parameters, and ion concentration to different levels of irrigation water salinity (ECiw of 0.9, 1.6, 2.7, 4.7 and 7.0 dS·m-1) and leaching fractions (LFs of 0.17, 0.29) were investigated in hot pepper plants. The pot experiment was conducted using a completely randomized block design with four replications in a rain shelter. Results showed that the height of the hot pepper plants decreased as the ECiw was increased from 25 d after transplanting (DAT) and increased when the LF was increased from 55 DAT. Neither the ECiw nor the LF influenced the root length. An increase in the ECiw caused the suppression of the stem diameter (SD); leaf length; leaf area; leaf chlorophyll content (CCI); dry biomass of roots, stems, and leaves; net photosynthesis (Pn); stomatal conductance (gS); transpiration rate (Tr); and intercellular CO2 concentration (Ci). An increase in the LF caused the SD, leaf length, leaf area, and dry biomass of stems and leaves to increase. However, the dry biomass of roots and the Pn, gS, Tr, and Ci were not significantly affected by the LF, except for the Ci measured on 23 DAT and the Tr on 76 DAT. The Na+ concentrations in the roots and stems increased, whereas the K+/Na+ ratios decreased as the ECiw increased. An increase in the LF led to a decrease in the Na+ concentration of the roots and stems, whereas there was an increase in the K+ concentration in the stems and the K+/Na+ ratios in the roots and stems. Collectively, an increase in the ECiw had an adverse effect on plant growth and gas exchange and led to the accumulation of the Na+ concentration in the roots and stems, whereas an increase in the LF enhanced plant growth, leaf transpiration, and K+ concentration and reduced the accumulation of the Na+ concentration in the roots and stems. We suggest that higher quantity of water should be applied in higher saline irrigation for satisfactory performance for hot pepper growth. [ABSTRACT FROM AUTHOR]

The change from deep-rooted grass and shrub vegetation to annual-cropping dryland farming has contributed to serious soil salinization challenges on the semi-arid North American Great Plains. In some cases, cultivation of the Great Plains has increased the availability of water, causing dominant sulfate salts to travel from the uphill areas to depressions where it will surface when water evaporates at the soil surface. A potential solution could include the replanting of the native deep-rooted vegetation, which requires knowledge of the spatial distribution of soil salinity. This study tested the soil factors influencing electromagnetic-induction meter (EM38) readings of soil salinity distribution around wetlands. The objectives were to: (1) predict growth and survival of Salix dasyclados Wimm. (cv. ‘India’) along a salinity gradient in a small wetland, and (2) investigate whether newly established willows affected water-table fluctuations, which would indicate their phreatophytic nature or their ability to obtain their water supply from the zone of saturation. Results indicated significantly lower salinity values for sampling points with EM38 readings above 175 and 250 mS m−1 for height and survival, respectively. In addition, diurnal fluxes of the water table in areas of good willow growth and lower salinity indicated that cultivar ‘India’ was phreatophytic in these areas and therefore has great potential for being used to combat saline seeps. [ABSTRACT FROM AUTHOR]

Natural springs have the potential to provide important information on hydrogeochemical processes within aquifers. This study used traditional and classic technical methods and procedures to determine the characteristics and evolution of springs to gain further knowledge on the differences between hot saline springs and cold fresh springs. In a short river segment near Wenquanzhen in the eastern Sichuan Basin, southwest China, several natural springs coexist with total dissolved solids (TDS) ranging from less than 1 to 15 g/L and temperatures from 15 to 40 °C. The springs emanate from the outcropping Lower and Middle Triassic carbonates in the river valley cutting the core of an anticline. The cold springs are of Cl·HCO3-Na·Ca and Cl·SO4-Na types, and the hot saline springs are mainly of Cl-Na type. The chemistry of the springs has undergone some changes with time. The stable hydrogen and oxygen isotopes indicate that the spring waters are of a meteoric origin. The salinity of the springs originates from dissolution of minerals, including halite, gypsum, calcite and dolomite. The evolution of the springs involves the following mechanisms: the groundwater receives recharge from infiltration of precipitation, then undergoes deep circulation in the core of the anticline (incongruent dissolution of the salt-bearing strata occurs), and emerges in the river valley in the form of hot springs with high TDS. Groundwater also undergoes shallow circulation in the northern and southern flanks of the anticline and appears in the river valley in the form of cold springs with low TDS. [ABSTRACT FROM AUTHOR]

Mycosporine‐like amino acids (MAA) are ultraviolet screen substances synthesized by marine algae. The physiological function of these substances is related to cellular protection against UV radiation and as a protective mechanism against oxidative stress. These substances can be found mainly in the ocean, among red seaweeds. Its concentration in organisms has been related to ultraviolet radiation and availability of inorganic nitrogen in the environment. We start our study of MAA content in different species to understand if environmental conditions influence the concentration of MAAs in red seaweeds. The Brazilian coast presents abiotic factors that interact to create different physical‐chemical features in the environment. We collected 441 samples from 39 species of red seaweed easily found in the intertidal zone, in low tide, during the summer of 2015. The sampling encompassed a latitudinal gradient (3° S to 28°5′ S) at 23 points along the coast. We quantified and identified the content of MAAs in species through the method of high performance liquid chromatography. We detected for the first time the occurrence of MAAs in certain species of red algae that have not been reported to contain MAAs before. We confirmed that some environmental factors influenced the content of MAAs. Enhanced MAA contents, for example, were found in environments with a basic pH, a high ultraviolet index, and high concentrations of phosphate and nitrate. Salinity, dissolved oxygen and variations of sea surface temperature also influenced, in a secondary way, MAA content in algae in their natural environments. [ABSTRACT FROM AUTHOR]

ABSTRACT Costa, M.S.; Rocha, A.S.; Santos, A.S., and Rolnic, M., 2018. Influence of tide on salt entrapment in the River Mojuim Estuary. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 81–86. Coconut Creek (Florida), ISSN 0749-0208. The aim of this study is to check whether there is salt entrapment in an estuary in the Amazon eastern coast. This study case was conducted in a section of the lower Mojuim River estuary. Tide, current, and water salinity were measured for 25 h during wet and dry seasons, 2014. Tide and salinity levels were recorded at fixed stations for 55 consecutive days during each season. Advective, diffusive, and dispersive salt transport and the Stratification/Circulation diagram were calculated. The Mojuim River estuary has a macrotidal, semidiurnal regime, with tide height of 4.9 m during spring tide and 3.2 m during neap tide. Maximum current intensities during wet season are 1.6 m.s−1 in flood tide and 1.9 m.s−1 in ebb tide, whereas during dry season, they are 1.2 m.s−1 in ebb tide and 1.6 m.s−1 in flood tide. Mean salinity increased from 7.3 g.kg−1 (±2.82) during wet season to 21.2 g.kg−1 (±3.62) during dry season. Advective salt transport was 736.4 kg.s−1 during wet season and 72.1 kg.s−1 during dry season, up-estuary and down-estuary, respectively. River discharge and Stokes transport are the predominant components of advective salt transport. It allows salt entrapment in the estuary during extreme tides, which might be retained in the floodplains. As the Mojuim river estuary is shallow (mean depth 4.5 m), the water column varies according to the fluvial component and to tides. Thus, the intensity of the fluvial component and tides during wet season promotes eddy mixture. During dry season, a decreased fluvial component due to low rainfall increases saline intrusion and causes the water column to be slightly stratified. The Mojuim river estuary was classified as well mixed during wet season and slightly mixed during dry season, according to the Stratification/Circulation diagram. [ABSTRACT FROM AUTHOR]

The aim of study is to determine the effect of NaCl salinity stress on germination characteristics and seedling growth of 5 Bulgarian sesame cultivars -Nevena, Aida, Milena, Sadovo 1 and Sofia. Five different concentrations of NaCl (25, 50, 100, 125 and 150 mM) are used as treatments and deionized water is used as control. To determine the salinity tolerance, the following germination characteristics -germination energy (%), germination percentage (%), coefficient of velocity of germination (% day-1), germination rate index and mean germination time (day) are studied. The data for the shoot and root length (cm), fresh weight (mg plant-1) of shoot and root and dry weight (mg plant-1) of shoot and root are measured ten days after germination. Vigour index and salt tolerance index are also calculated. Correlations between investigated characters are determined. The effect of increasing NaCl levels on germination energy and final germination percentages are not recorded. Increasing salinity concentration from 0 to 150 mM NaCl prolonged mean germination time. Increasing salt concentration had an inhibitory effect on the initial seedling growth. Sofia cultivar is the most tolerant at seedling growth stage and Milena is the most sensitive variety. [ABSTRACT FROM AUTHOR]

The red seaweed Gracilaria fisheri has been used for human food, for marine animal feeding, and for agar extraction. This algal species is extensively cultured, but its production is often unpredictable due to lack of basic biological information on this species. This work aims to determine the effects of irradiance, salinity and temperature on the photosynthesis of this species. Plants were subjected to different irradiance (0-1150 μmol photons.m-2s-1), salinity (15--40%o), and temperature (12--40°C) levels in a growth chamber. Photosynthesis was determined using a dissolved oxygen sensor and pulse amplitude-modulated fluorometry. The results showed rapid light curves increasing with irradiance up to 1150 fimol photons.m-2.s-1. The highest Pnet was obtained at 203 jimol photons.m-2-s-1, temperature 24°C and a salinity of 30%o, which also corresponded to the highest maximum quantum yield. Our study revealed that the Pnet rates were highest from 24--28°C at an irradiance of 203 μmol photons.m-2.s-1 and was lower at higher and lower temperatures. [ABSTRACT FROM AUTHOR]

Low salinity water flooding appears to be a cost-effective and environmentally friendly means to shift wettability of oil/brine/rock system towards more water-wet, thus improving hydrocarbon recovery. While the contribution of kaolinite (edge-charged clays) on low salinity effect has been extensively investigated, how basal-charged clays (e.g., illite, smectite, and chlorite) contributing to the low salinity effect remains unclear. We thus hypothesize that low salinity water facilitates ion exchange in the presence of basal charged clays, thus lifting off oil films from pore surfaces. To test the hypothesis, we performed a geochemical study using PHREEQC in light of double layer diffuse theory. We quantitatively interpreted the pH increase and low salinity effect from corefloods conducted by RezaeiDoust et al. [RezaeiDoust A, Puntervold T, Austad T. Chemical verification of the EOR mechanism by using low saline/smart water in sandstone. Energy & Fuels. 2011;25(5):2151–62.]. We demonstrate that low salinity water triggers a pH increase at the presence of basal-charged clays, thus a more water-wet because of ion exchange. We therefore expand the application envelope of low salinity water flooding to reservoirs with basal-charged clays. [ABSTRACT FROM AUTHOR]

An optical fiber sensor is fabricated and characterized in this communication for salinity detection. The proposed sensor consists of a multimode fiber (MMF) and a section of no core fiber (NCF) with a round tip. The sensor detects the intensity variation of the back reflected light caused by changing concentration of the salt solution surrounding the probe. The parameters of the sensor were studied for better performance. A down tapering is also introduced to enhance the sensitivity of the sensor and a high sensitivity of 0.773 dB/% is obtained for a salinity range of 0–20%. Due to its high sensitivity, low cost and compact size, the proposed sensor can be very much useful in water quality monitoring for environmental, healthcare and industrial applications. [ABSTRACT FROM AUTHOR]

The use of a hydrate-based technology in seawater desalination is an interesting potential hydrate application since salt ions would be excluded from the hydrate crystal lattice. In order to better understand the hydrate-based desalination process, experiments have been conducted using cyclopentane (CyC5, sII) hydrates, which can be formed at atmospheric pressure and temperatures below 7.7 °C. The hydrate formation experiments were performed at various subcoolings for aqueous solutions with different salinities in a bubble column. The hydrate formation times decreased and the hydrate conversion increased with increasing subcooling and agitation. Various hydrate-former injection methods were studied, with the most effective method involving spraying finely dispersed CyC5 droplets (around 5 µm in diameter) into the water-filled bubble column. The latter method resulted in a 2-fold increase in seawater conversion to hydrate crystals compared with injecting millimeter-scale CyC5 droplets. A desalination efficiency of 81% (the salinity decreased from 3.5 to 0.67 wt %) was achieved by using a three-step separation method, including gravitational separation, filtration, and a washing step. Washing the hydrate sample using filtered water decreased the salinity from 1.5 wt % in the solid hydrates before washing to 1.05 wt % after washing. [ABSTRACT FROM AUTHOR]

A new sensing method for simultaneous measurement of seawater temperature and salinity by C-type micro-structured fiber was proposed. The C-type fiber structure formed by removing the outer wall of one pore from a six holes micro-structured fiber, which would bring in birefringence and broke original pattern of degeneracy. By optimizing the parameters of this fiber structure, X polarization and Y polarization of fundamental mode were separate. Therefore, it could be used for double parameter measurement. Besides, gold film coated on the surface of structure to enhance sensing sensitivity by Surface Plasmon Resonance (SPR) principle. In this study, finite element analysis method was used to analyze the spectral transmission characteristics of C-type micro-structured optical fiber. The surface of wedge-shaped defect was contacted with seawater directly to feel salinity; meanwhile, thermo-optic material filled into pores to detect the temperature of seawater. Through model analysis, it was proved that the proposed filling structure could produce two SPR loss valleys, which had different responses to temperature and salinity. Under optimized structure, maximum salinity sensitivity of 1.402 nm/‰ was obtained for X-polarization and maximum temperature sensitivity of −7.609 nm/ °C was obtained for Y polarization, which demonstrated that the designed scheme could not only solve the cross sensitivity problem of two parameters but also achieve high sensitivity. In addition, C-type micro-structured fiber is non-cascade integrated, strong stability, and flexibility in design, which has great potential for sensing applications. [ABSTRACT FROM AUTHOR]

The goal of this paper is to quantify the atmospheric influence, i.e. the influence of wind in particular, on the sea dynamics in the Rijeka Bay (Adriatic Sea). This quantification is important for city sewage disposal and dispersion as well as surface pollution dispersion. We compare the effect of jugo (sirocco) and bora winds on a calm period. The resulting simulations show that the bora conveys the surface layer of sea water out of the bay through the Middle and the Great Gate while deep cold water enters the bay through the same gates. The mean vertical upward velocity component close to the coast is about 1 mm s-1. This is sufficient to rise cold water near the city of Rijeka to the surface in three hours and to significantly cool the surface layer during summer. For the south-east wind (jugo) the situation is reverse: the warmer surface sea water enters the bay through the Middle and the Great Gate, while the colder bottom sea water exits the bay through the Middle and the Great Gate, accumulating the warmer sea water in the bay. In the case of no wind the surface velocity vectors (at depths of 0.5 m) are disordered and do not follow any particular pattern while the movements at 12 m, 24 m, 36 m, 48 m, and 60 m show dominant flow from the western coast (of the island Krk) toward the eastern coast of the Istrian peninsula. [ABSTRACT FROM AUTHOR]