Saline water

Reverse osmosis membrane technology has developed over the past 40 years to a 44% share in world desalting production capacity, and an 80% share in the total number of desalination plants installed worldwide. The use of membrane desalination has increased as materials have improved and costs have decreased. Today, reverse osmosis membranes are the leading technology for new desalination installations, and they are applied to a variety of salt water resources using tailored pretreatment and membrane system design. Two distinct branches of reverse osmosis desalination have emerged: seawater reverse osmosis and brackish water reverse osmosis. Differences between the two water sources, including foulants, salinity, waste brine (concentrate) disposal options, and plant location, have created significant differences in process development, implementation, and key technical problems. Pretreatment options are similar for both types of reverse osmosis and depend on the specific components of the water source. Both brackish water and seawater reverse osmosis (RO) will continue to be used worldwide; new technology in energy recovery and renewable energy, as well as innovative plant design, will allow greater use of desalination for inland and rural communities, while providing more affordable water for large coastal cities. A wide variety of research and general information on RO desalination is available; however, a direct comparison of seawater and brackish water RO systems is necessary to highlight similarities and differences in process development. This article brings to light key parameters of an RO process and process modifications due to feed water characteristics.

1.Razor clams are found in different habitats ranging from sheltered systems (e.g. lagoons and estuaries) to open coasts. They are distributed worldwide and comprise a small number of species of high economic value. Depending on the specific habitat and species exploited, different mechanical and hand-harvesting techniques are employed. While the environmental effects resulting from mechanized methods have been described by several authors, the impacts caused by traditional hand-harvesting methods remain unknown. Therefore, a study was undertaken in Ria Formosa lagoon (South of Portugal) addressing the environmental effects resulting from harvesting Solen marginatus with salt.2.No significant impact on the sediment was found; the main effect was an increase in salinity after covering the area with salt, which decreased rapidly with the flood tide and after a few hours had returned to pre-harvesting levels.3.No effects on benthic communities were observed, with similar fluctuation patterns recorded in control and experimental areas, the observed differences being attributed to the natural variability of benthic populations.4.Based on the results obtained in the present study, a razor clam fishery using salt in intertidal areas can be considered environmentally ‘friendly’. Copyright © 2008 John Wiley & Sons, Ltd.Razor clams are found in different habitats ranging from sheltered systems (e.g. lagoons and estuaries) to open coasts. They are distributed worldwide and comprise a small number of species of high economic value. Depending on the specific habitat and species exploited, different mechanical and hand-harvesting techniques are employed. While the environmental effects resulting from mechanized methods have been described by several authors, the impacts caused by traditional hand-harvesting methods remain unknown. Therefore, a study was undertaken in Ria Formosa lagoon (South of Portugal) addressing the environmental effects resulting from harvesting Solen marginatus with salt.No significant impact on the sediment was found; the main effect was an increase in salinity after covering the area with salt, which decreased rapidly with the flood tide and after a few hours had returned to pre-harvesting levels.No effects on benthic communities were observed, with similar fluctuation patterns recorded in control and experimental areas, the observed differences being attributed to the natural variability of benthic populations.Based on the results obtained in the present study, a razor clam fishery using salt in intertidal areas can be considered environmentally ‘friendly’.

There is increasing evidence that nitrogen limitation is of widespread occurrence in tropical lakes. Nonetheless, data on the deep tropical Lake Alchichica (Mexico) show that dissolved inorganic nitrogen (DIN) to soluble reactive phosphorus (SRP) ratio fluctuates widely. To elucidate further the role of nitrogen and phosphorus limitation on the phytoplankton growth in tropical saline lakes, we present the results of a series of nutrient enrichment experiments with natural assemblages of Lake Alchichica phytoplankton conducted monthly for a year. Our assays indicate that phosphorus and nitrogen alternate in limiting Lake Alchichica phytoplankton biomass. Phosphorous limited phytoplankton growth most (41.7%) of the time, followed by nitrogen (33.3% of the time), and both nutrients for the rest of the time (25.0%). This alternation in nitrogen and phosphorus responsible for phytoplankton growth limitation in Lake Alchichica is attributed to the combination of natural conditions (e.g., young volcanic terrain rich in phosphorus) that would favor nitrogen limitation and anthropogenic impacts (e.g., agricultural nitrogen fertilization) which would cause phosphorus limitation.

Doxorubicin (DOX) is an anthracycline antibiotic that is widely used as an anticancer agent. However, the clinical use of DOX is limited due to its cardiotoxic side effects. Few studies have assessed pretreatment effects of chronically exercise against doxorubicin-induced cardiotoxicity. The aim of this study was to determine cardioprotective effects of aerobic regular exercise against doxorubicin-induced oxidative stress in rat. Forty-eight Wistar male rats were randomly assigned to sedentary and trained groups. Training program included treadmill running between 25 to 54 min/day and 15 to 20 m/min, 5 days/week for 6 weeks. The biomarkers related to oxidative stress were assessed in heart tissue after administration of the saline solution (0.9% NaCl i.p) and/or DOX 20 mg/kg and DOX 10 mg/kg. Doxorubicin administration (10 and 20 mg.kg_1) causes an imbalance in the oxidant/antioxidant markers in heart. Six weeks of the aerobic training led to a significant increase of apelin, nitric...

Urban expansion and the associated increase in anthropogenic pressures have led to a great loss of the Red Sea's biodiversity. Floristic composition, diversity, and environmental controls were investigated for 210 relevés on twenty coral islands of Farasan in the Red Sea, Saudi Arabia. Multivariate statistical analyses for classification (Cluster Analysis), ordination (Detrended Correspondence Analysis (DCA), and Redundancy Analysis (RDA) were employed to identify vegetation types and their relevance to the underlying environmental gradients. A total of 191 flowering plants belonging to 53 families and 129 genera were recorded. Geophytes and chamaephytes were the main life forms in the saline habitats, whereas therophytes and hemicryptophytes dominated the sandy formations and coral rocks. The cluster analysis and DCA ordination identified twelve vegetation groups that linked to five main habitats with definite floristic composition and environmental characteristics. The constrained RDA with Monte Carlo permutation tests revealed that elevation and soil salinity were the main environmental factors explaining the vegetation distributions. These results indicate that the flora of the study archipelago represents a phytogeographical linkage between Africa and Saharo-Arabian landscape functional elements. These findings should guide conservation and management efforts to maintain species diversity, which is threatened by anthropogenic activities and invasion by the exotic invasive tree Prosopis juliflora (Sw.) DC.

There is increasing evidence that nitrogen limitation is of widespread occurrence in tropical lakes. Nonetheless, data on the deep tropical Lake Alchichica (Mexico) show that dissolved inorganic nitrogen (DIN) to soluble reactive phosphorus (SRP) ratio fluctuates widely. To elucidate further the role of nitrogen and phosphorus limitation on the phytoplankton growth in tropical saline lakes, we present the results of a series of nutrient enrichment experiments with natural assemblages of Lake Alchichica phytoplankton conducted monthly for a year. Our assays indicate that phosphorus and nitrogen alternate in limiting Lake Alchichica phytoplankton biomass. Phosphorous limited phytoplankton growth most (41.7%) of the time, followed by nitrogen (33.3% of the time), and both nutrients for the rest of the time (25.0%). This alternation in nitrogen and phosphorus responsible for phytoplankton growth limitation in Lake Alchichica is attributed to the combination of natural conditions (e.g., young volcanic terrain rich in phosphorus) that would favor nitrogen limitation and anthropogenic impacts (e.g., agricultural nitrogen fertilization) which would cause phosphorus limitation.

Open drainage ditches located in low permeability material can interact with an underlying aquifer, especially if the drains almost or totally penetrate through to the aquifer. This interaction can be represented by drain coefficients incorporated in regional groundwater models. The drain coefficients depend on both the vertical distance from the base of the drain to the aquifer and the hydraulic conductivities of the low permeability deposits and the underlying aquifer. In a case study of drained marshes in the Thurne catchment in Norfolk, UK, drains with a water level below ordnance datum (OD) draw in saline water from the coast and freshwater from recharge areas. Pathlines, derived from a regional groundwater model analysis, explain the salinities measured in drains. In addition a series of vertical section numerical model solutions are used to develop general guidance on the selection of drain coefficients.

O uso de água salina na irrigação torna-se importante alternativa diante daescassez de água de boa qualidade em todo o mundo. O pinhão-manso (Jatropha curcas L.) possui baixa exigência hídrica, sobrevive e apresenta produção satisfatória em solos de baixa fertilidade. No entanto, a sua produção é maior em cultivos irrigados, o que reforça a necessidade de desenvolvimento de pesquisas para uso de água salina. Este trabalho objetivou avaliar o efeito de diferentes níveis de salinidade da água de irrigação nas características morfofisiológicas de mudas de pinhão-manso. Para isso, foi conduzido experimento em casa de vegetação com interceptação de 50 % da radiação solar, localizada na Universidade Estadual de Goiás, Ipameri, Goiás. O experimento foi conduzido em vasos com capacidade de 4 L de solo, utilizando-se o delineamento inteiramente casualizado, com quatro tratamentos e cinco repetições. As plantas foram irrigadas diariamente com 150 mL de água não salina, durante os 30 primeiros...

In this study, the effect of salinity (150 mM NaCl) compared to a control (9 mM NaCl) on growth, quality and shelf-life of fresh-cut sea fennel was evaluated. For that, sea fennel plants were cultivated in a hydroponic floating system and the sea fennel leaves were stored for 12 days at 5 °C. At harvest, leaves from plants grown in salinity had a lower content of NO3−, K+ and Ca2+ and an increased Cl− and Na+ concentration when compared to the control. There was a positive effect in the aerial part with increased fresh weight due to salt stress, but a reduction in the root biomass. During storage, weight loss and colour changes were not significant while leaves’ firmness was higher for control and increased during storage, probably due to lignification. Microbial growth (psychrophiles, yeast and moulds and enterobacteria) was higher at harvest for control and increased during storage, with no differences between treatments after 12 days at 5 °C. Sensory quality was similar for both ...

Saline water intrusion into freshwater aquifers is a major geohydraulic problem relevant to coastal environment. Apart from contaminating the fresh groundwater resources, the saltwater intrusion alters the geotechnical properties of the aquifer materials, affecting the coastal water resource planning and management. The present study focuses on an in-depth laboratory investigation of the influence of saltwater submergence on the geohydraulic properties of sand. The fine sand sample was submerged under saline water of specified concentrations for specific periods, and the alteration in their engineering properties has been studied. It is observed that the specific gravity, dry density, and permeability of fine sand is significantly affected by the period of submergence and saline concentration. The specific gravity of sand particles was observed to increase almost linearly with period of submergence and saline concentration. While the sand dry density decreased fairly linearly with t...

Coastal zones are becoming more hazardous due to increased population and greater susceptibility to flooding and salinization, as a result of compaction and subsidence, surface sealing and loss of buffer zones between the coast and settled areas. These conditions are exacerbated in the developing (largely equatorial) world, where rates of population increase are highest and protection schemes and mitigation strategies

Background and objectives: Accurate planning is very important for optimized use of water resources in agricultural sector due to climate condition of Iran. According to the research results, drought and salinity are two factors limiting agricultural production in arid and semi-arid. Since changing drought or salinity adjust or increase other effect on plant, it is necessary evaluating combined effects of drought and salinity on plants such as date palm. In this reseach, the effect of water stress and salinity were studied in vegetative growth stage of Barhee date.
Materials and methods: This research was carried out in factorial method based on randomized complete design with three replications on Barhee juvenile date palms. The treatments were three irrigation depths of 100%, 85% and 70% of plant water requirement and three irrigation water salinities of 2.5, 8 and 12 dS/m. The irrigation depth was calculated by measuring soil moisture. The production functions of water-salinity-dry matter yield were determined in linear, Cobb-Douglas, quadratic and transcendental equations. Five statistical indices of adjusted coefficient of determination (R2adj), modeling efficiency (EF), maximum error (ME), normalized root mean square error (nRMSE) and coefficient of residual mass (CRM) were used in evaluation of models.
Results: The results showed that irrigation depth, water salinity and interaction of irrigation depth and water salinity had significant effect on all vegetative characters of plant except shoot relative water content. Decreasing irrigation depth from 100% to 85% of plant water requirement showed non-significant decrease in mean of shoot wet and dry matter that were only 5.0 and 5.6 percent, respectively. Amounts of these characters decreased significantly 26.3 and 24.4 percent, respectively, in irrigation depth equal 70% of plant water requirement. While, increasing water salinity from 2.5 to 8 dS/m was caused significant decrease in mean of shoot wet and dry matter that were 44.0 and 42.0 percent, respectively. Amounts of these characters decreased 54.1 and 52.0 percent, respectively, in irrigation with water 12 dS/m. The most amounts of plant vegetative characteristics obtained from water salinity of 2.5 dS/m and irrigation depth equal 100% of plant water requirement. This treatment had significantly different with other treatments expect water salinity of 2.5 dS/m and irrigation depth equal 85% of plant water requirement.
Conclusion: The Barhee juvenile date palms can be irrigated with 85% of water requirement when water salinity is 2.5 dS/m. The comparison of production functions of water-salinity-dry matter yield showed that quadratic equation had more accuracy than other equations in estimation of dry matter yield in vegetative growth phase of Barhee date palm. All equations estimated shoot dry matter less than actual amount expect quadratic equation.

The objective of this work was to study the effects of irrigation with saline water associated with phosphate fertilization on the emergence and early growth of cowpea plants. The assay was conducted in the greenhouse of the Department of Environmental Sciences and Technology of the Federal Rural University of the Semi-Arid (UFERSA) in Mossoró-RN, during October and November of 2015. The study adopted a randomized block with treatments arranged in a 5 x 3 grid, corresponding to five levels of water salinity (0.5, 1.5, 2.5, 3.5 and 4.5 dS m-1) and three doses of superphosphate, based upon the soil analysis (60%, 100% and 140% of the recommended dose for the crop 60 kg P2O5 ha-1), with five repetitions. The cowpea plants, cv. Paulistinha, were grown in lysimeters with capacity of 8 dm 3. During the first 15 days of the initial stage of development the plants were evaluated for emergence, growth and biomass accumulation. The increase in water salinity above 1.5 dSm-1 reduced the emergence, growth and dry matter accumulation of cowpea plants. The increase of 40% in the recommendation of phosphorus fertilization of cowpea increased the growth and biomass accumulation of shoot plants, regardless of salinity.

Pterocladia capillacea, a red marine macroalgae, was tested for its ability to remove toxic hexavalent chromium from aqueous solution. A new activated carbon obtained from P. capillacea via acid dehydration was also investigated as an adsorbent for toxic chromium. The experiments were conducted to study the effect of important parameters such as pH, chromium concentration and adsorbent weight. Batch equilibrium tests at different pH conditions showed that at pH 1.0, a maximum chromium uptake was observed for both inactivated dried red alga P. capillacea and its activated carbon. The maximum sorption capacities for dried red alga and its activated carbon were about 12 and 66 mg g−1, respectively, as calculated by Langmuir model. The ability of inactivated red alga P. capillacea and developed activated carbon to remove chromium from synthetic sea water, natural sea water and wastewater was investigated as well. Different isotherm models were used to analyze the experimental data and the models parameters were evaluated. This study showed that the activated carbon developed from red alga P. capillacea is a promising activated carbon for removal of toxic chromium.

Two pot experiments were conducted to study differential response of some potato varieties (Diamant,
Lady Rosetta and Spunta) to irrigation with different saline water levels. After completing emergence (30 days
after planting) potato varieties were irrigated with saline water at concentrations of 1.5, 3.0, 4.5 and 6.0 dS/m
beside the control 0.4 dS/m (tap water). The results showed that all measured growth characteristics were
gradually decreased when potato plants were irrigated with saline water up to 6.0 dS/m. Saline treatments
decreased significantly stem length, number of leaves, leaves dry weight, tuber dry weight, total plant dry
weight and leaf area per plant. Higher saline levels, i.e., 4.5 or 6.0 dS/m caused a significant reduction in tuber
number, average tuber weight and total tuber fresh weight per plant in both summer seasons. Regarding tested
potato variety, Diamant potato variety was the most tolerant to saline water irrigation, Lady Rosetta was the
second tolerant variety and Spunta was the least tolerant variety in both seasons.

High groundwater salinity, a high water table and secondary soil salinization are dominant conditions in eastern Isfahan Province, Iran . This region has a low annual rainfall, high annual evaporation demand, saline soils and limited fresh water supplies. To investigate the effects of irrigation deficit and salinity on cantaloupe ( Cucumis melo L. var. cantalupensis ) production, a field experiment was performed at the Salinity and Drainage Research Station of Rudasht, 65 km East of Isfahan. Irrigation treatments were T65, T80 and T95 (irrigation after 65, 80 and 95 percent of cumulative evaporation from Class A pan, respectively), each having three replicates. EC of irrigation water was 5.25 dS m -1 ; irrigation water depth for the whole growing period was 300, 342 and 384 mm, for T65, T80 and T95 treatments, respectively. The results showed that T65 and T80 irrigation treatments significantly reduced fresh yield, number of fruit, fruit weight per plant and water use efficiency. Fr...

Salt tolerance of five cultivars of Capsicum annuum L. Early Jalapeno, Golden Treasure, NuMex Sweet, NuMex Joe E. Parker, and Santa Fe Grande, two cultivars of C. chinense Jacq. Habanero and Pimienta De Chiera, and one accession of C. annuum, NMCA 10652, were ...

El presente trabajo tiene por objeto evaluar la uniformidad del riego por goteo en las zonas de regadio de las cuencas de los rios Mendoza y Tunuyan (zonas Alta y Baja), de la provincia de Mendoza, Argentina. Las evaluaciones -en 17 propiedadespermitieron determinar: coeficientes de uniformidad, salinidad del agua de riego y del suelo en cabeza, medio y pie de la subunidad de riego, y en el bulbo humedo e interfilar en dos estratos del perfil del suelo (0,10-0,30 m y 0,30-0,50 m). Se determino, ademas, la textura del suelo y su posible relacion con los niveles de salinidad de la rizosfera. Se estimo que el 18% de las subunidades de riego evaluadas presentan un coeficiente de uniformidad por debajo del rango recomendable y que en el 94% de las propiedades existen diferencias significativas entre caudales medios registrados entre subunidades y entre sectores de operacion de riego. Se encontraron diferencias significativas en la salinidad del extracto de saturacion, en la sodicidad y e...