Concentrations Of Saline Water Research Articles

An Experimental Investigation on the Performance Analysis of Two-Stage Desert Cooler

The present experimental investigation reports the performance of both the single and two stage direct evaporative cooling systems in composite climatic conditions of Patna, India. A two-stage direct evaporative cooling system has been designed and fabricated. The first stage of the two-stage cooling system utilizes a heat exchanger designed internally to sensibly cool hot and arid ambient air. The effect of varying the frontal air velocity (0.5–9 m/s) and different saline water concentration (5–10%) on the performance of two stage direct evaporative cooler is investigated. The maximum effectiveness of single and two-stage desert cooler is found to be 0.7 and 0.98 at frontal velocity of 2 m/s and 2.5 m/s, respectively. The performance of the two-stage cooler with tap water is found to be 40% higher than the single stage desert cooler. The effectiveness of single and two stage desert coolers with tap water is found to be in the range of 6–11% and 9.3–14% higher compared to the saline water at salt concentrations of 5–10%, respectively. Moreover, increasing salt concentration leads to reduced relative humidity at the cooler exit, with the two-stage cooler exhibiting 28.5% lower relative humidity than single-stage desert cooler.

Single modular flow-electrode capacitive deionization using modified Prussian blue analogues as cation intercalation electrode for continuous water desalination.

Ion back-diffusion hinders the practical application of conventional flow-electrode capacitive deionization (FCDI) under long-term operational conditions. To address this challenge, the present study integrated cation intercalation deionization (CID) with FCDI. A novel PFCDI-CID system was developed by utilizing a modified Prussian blue analogues owing to their enhanced rheological and electrochemical properties. The PFCDI-CID system achieved a high charge efficiency of 89.77% and an energy-normalized removal salt of 0.69 mol kJ-1 in single-cycle (SC) mode with the flow electrodes mass fraction of 2% and a desalinized water chamber-to-concentrated saline water chamber ratio of 2:1. Furthermore, under continuous operation for 12 h in SC mode, the PFCDI-CID system maintained stable desalination performance within the first 2 h. Over an extended duration, the average charge efficiency of the PFCDI-CID system was maintained at 88.44%, with an average energy-normalized removal salt of 0.65 mol kJ-1. The mechanism revealed that the desalination process involving the Prussian blue analogues primarily involves Na+ intercalation, accompanied by a small amount of electro-sorption process. This system exhibits the characteristics of conventional FCDI while enabling desalination and concentration of simulated saline water during brine discharge, thereby mitigating the impact of ion back-diffusion and broadening the application scope of FCDI.

The Effect of Saltwater Stress on the Performance of Cherry Tomatoes

Rising sea levels and saltwater intrusion in aquifers pose significant challenges for South Florida agriculture, leading to increased groundwater salinity and potential crop losses. Utilizing salttolerant crop species presents a potential solution for saline soils and regions with active saltwater intrusion. However, the effects of soil salinization through groundwater alone remains less studied. This research investigates the impact of short-term, below-ground saltwater stress on the growth, survival, and overall health of commonly grown cherry tomatoes (Solanum lycopersicum). The objectives of the study are to: 1) determine the impact of saline groundwater on tomato plant health and 2) compare the nutrient content of soil and tomato plant tissue exposed to varying concentrations of saline water. Established cherry tomato plants were exposed to varying concentrations of NaCl solution, simulating saltwater intrusion into groundwater. Over 28 days, plant height, leaf chlorophyll levels, and disease occurrences were monitored. It was found that the NaCl treatments did not significantly affect cherry tomato performance under the parameters of height, chlorophyll levels, or leaf nutrition when compared to the control group. This study suggests that cherry tomatoes can tolerate short-term exposure to NaCl in groundwater. Further exploration of more intense salt stress conditions from groundwater could be beneficial for utilizing this crop in areas with saline soils or polluted groundwater. Identification of salt-tolerant cherry tomato varieties can provide alternative crop options for non-arable land affected by high soil salinity.

Effect of PFDS on the immobilization of Cs+ by metakaolin-based geopolymers in complex environments

Metakaolin-based geopolymers are very promising materials for improving the safety of low and intermediate level radioactive waste disposal, with respect to ordinary Portland cement, due to their excellent immobilization performance for Cs+ and superior chemical stability. However, their application is limited by the fact that the leaching behavior of Cs+ is susceptible to the presence of other ions in the environment. Here, we propose a way to modify a geopolymer using perfluorodecyltriethoxysilane (PDFS), successfully reducing the leaching rate of Cs+ in the presence of multiple competitive cations due to blocking the diffusion of water. The leachability index of the modified samples in deionized water and highly concentrated saline water reached 11.0 and 8.0, respectively. The reaction mechanism between PDFS and geopolymers was systematically investigated by characterizing the microstructure and chemical bonding of the material. This work provides a facile and successful approach to improve the immobilization of Cs ions by geopolymers in real complex environments, and it could be extended to further improve the reliability of geopolymers used in a range of applications.

Flexible construction of three-dimensional continuous conductive structure by hollow carbon sphere and CNT for promoted ions transport in flow-electrode capacitive deionization

Flow-electrode capacitive deionization (FCDI) emerges as a promising desalination technique, characterized by its unlimited desalination capacity, seamless operation, and easy scalability. However, challenges such as discontinuous electronic network, inadequate dispersion of suspended carbon particles, and hindered electron/ion transport pathways have impeded the full potential of FCDI. This study addresses the above issues by synergistically leveraging the advantage of hollow carbon sphere (HCS) and CNT to construct a flexible, continuous three-dimensional conductive network (HCS@CNT) as the flow-electrode for FCDI. The incorporation of HCS substantially improves the fluidity and effective collision of the flow-electrode slurry. Simultaneously, the bridging effect of CNT facilitates smooth ion transport routes and rapid electron/ion transfer. Moreover, the spherical structure of HCS as a node can effectively alleviate the agglomeration of CNT due to its inherent good fluidity. As a result, the meticulously designed HCS@CNT flow-electrode demonstrates outstanding rheological behavior with excellent hydrophilicity, a large specific capacitance, and low ion diffusion resistance. During desalination tests, the HCS@CNT flow-electrode exhibited a high average salt removal rate (0.56 µmol min−1 cm−2), appropriate energy-normalized removal salt (15 µmol J−1), and notable charge efficiency (89 %) in a 1 g L-1 NaCl solution. Impressively, it maintained good stability and continuity over a continuous 10-hour desalination process, showcasing substantial potential for treating highly concentrated saline water. In addition, density functional theory (DFT) calculations provided additional insights, confirming that the construction of HCS@CNT facilitated interfacial charge transfer and electron transport from HCS to CNT. This innovative approach sheds light on enhancing electron/ion transfer by harnessing the unique structural characteristics of the flow-electrode.

The efficacy of ammonium as seed priming agents for promoting tomato (<i>Solanum lycopersicum</i> L.) germination under salinity stress

The aim of the current study was to assess the effectiveness of NH<sub>4+</sub> priming to enhance tomato seed germination and plant growth under saline stress. In the absence of light at 25 ± 1 °C, tomato seeds were primed with 50 and 100 mmol of NH<sub>4</sub>NO<sub>3</sub> and with 50 and 100 mmol of (NH<sub>4</sub>)<sub>2</sub>SO<sub>4</sub> for 12 and 24 h, respectively. In the seed germination test, twenty primed seeds were used for each treatment, along with five replica plates and a control, and were all incubated at 25°C with 25 mL of moistened water. In a second greenhouse experiment, primed seeds were planted in garden soil and watered with tap water, salt water, and a control. The concentration of saline water (50, 100, 150, and 200 mmol NaCl) was gradually raised after a 10-day break. The germination percentages in T5 (50 mmol (NH<sub>4</sub>)<sub>2</sub>SO<sub>4</sub>, 12 hrs) were 82±3.7% and 80±4.47 %, respectively, followed by T1 and T3 (50 mmol (NH<sub>4</sub>)<sub>2</sub>SO<sub>4</sub>, 12 h and 100 mmol NH<sub>4</sub>NO<sub>3</sub>, 12 h). When compared to the unprimed tomato seeds, the NH<sub>4+</sub> priming with NH<sub>4</sub>NO<sub>3</sub> and (NH<sub>4</sub>)<sub>2</sub>SO<sub>4</sub> improved plant height and other growth parameters. Furthermore, the chlorophyll and total flavonoid content were improved in both saline and non-saline treatments. In terms of salinity, the NH<sub>4+</sub> priming increased the proline content while decreasing the total protein content. It is concluded that further research will be needed to clarify the effect of NH<sub>4</sub>NO<sub>3</sub> and (NH<sub>4</sub>)<sub>2</sub>SO<sub>4</sub> as NH<sub>4+</sub> priming in tomato plants because other factors and nutrition can play a role in seed germination and plant growth development.

A novel suspended suspension bridge-like evaporator with antibacterial properties for achieving stable solar evaporation in concentrated saline water

Salt crystallization and microbial corrosion limit the operation of green and energy-efficient solar-driven evaporation. To enhance the solar evaporation efficiency and achieve the stable evaporation while inhibiting salt crystallization in high-concentration saltwater, this study introduces a novel suspended suspension bridge-like evaporator (CF-Ag-PPy) composed of polypyrrole (PPy), silver (Ag) nanoparticles, and the cotton fabric. CF-Ag-PPy, hanging between two water reservoirs, leverages capillary action, gravity, and siphon effect to draw water from both ends immersed in water to form a suspension bridge-like evaporating surface. This design ensures continuous water supply to the evaporating surface while avoiding direct contact with the water, thereby minimizing additional heat losses and resulting in a high evaporation rate of up to 1.55 kg m−2 h−1. Owing to the siphon effect, the difference in water level height between the supply water and the bottom of the evaporating interface controls the droplet falling speed, so that the evaporator achieves continuous operation at a high evaporation rate of over 1.2 kg m−2 h−1 for six days in 20 wt% high-concentration saltwater, with no salt crystallization formation. This demonstrates the excellent salt resistance of the evaporator. Additionally, the Ag+ ions generated by Ag nanoparticles effectively exhibit antibacterial properties, with a bacterial inhibition rate of up to 99.95 % against specific bacteria, effectively preventing microbial corrosion. This study provides an important design concept for achieving long-term, stable, and efficient purification of high-concentration saltwater in natural environments using solar evaporators.

Enhancing Chickpea (Cicer arietinum L.) Tolerance to Salinity through Plant Growth Regulators

During the period of 2020-21, a research study was carried out at the Plant Protective Culture Unit within the semi-controlled environmental settings of the Bangladesh Agricultural Research Institute. The aim of the study was to mitigate the negative impacts of salinity stress on chickpea by applying various concentrations of salicylic acid (SA) and gibberellic acid (GA3). Plants were subjected to four different levels of salinity stress, including a control group, mild stress, moderate stress, and severe stress. This was achieved by irrigating them with four varying concentrations of saline water (5, 7.5, 10 and 12.5 dSm-1) starting from the 14th day after sowing (DAS) and continuing until maturity at 100 DAS. On the other hand, the control plants received regular irrigation with tap water. Two concentrations of salicylic acid (SA) specifically 200 ppm and 400 ppm, along with gibberellic acid (GA3) at 10 ppm and 20 ppm, were administered as a foliar spray once a week, commencing at 20 days after sowing (DAS) and continuing until the flowering stage. Data related to chlorophyll levels in the leaves and water-related traits, including relative water content (RWC) and water retention capacity (WRC) were collected seven days after the foliar spray of these plant growth regulators at the flowering stage. Additionally, measurements of total dry weight, yield, and various yield-contributing factors were taken at the point of maturity. The results indicated that chickpea suffered adverse consequences due to salinity stress which included a reduction in chlorophyll content, a decrease in relative water content, a decline in water retention capacity, a decrease in total dry weight and a lower overall yield. However, the foliar application of different doses of salicylic acid (SA) and gibberellic acid (GA3) under varying levels of salinity stress had beneficial effects in alleviating the impact of salinity stress. Interestingly, it was observed that lower concentrations of SA at 200 ppm and GA3 at 10 ppm were more effective in mitigating the adverse effects of salinity stress and improving salinity tolerance in chickpea, especially under mild salinity stress conditions (5 dSm-1) as evidenced by the positive influence on the parameters mentioned above.

Ethyl cellulose composite membranes containing a 2D material (MoS2) and helical carbon nanotubes for efficient solar steam generation and desalination

With the increasing water consumption, water evaporators have been investigated for clean water production. Herein, the fabrication of electrospun composite membrane evaporators based on ethyl cellulose (EC), with the incorporation of light-absorption enhancers 2D MoS2 and helical carbon nanotubes, for steam generation and solar desalination is described. Under natural sunlight, the maximum water evaporation rate was 2.02 kg m−2 h−1 with an evaporation efficiency of 93.2 % (1 sun) and reached 2.42 kg m−2 h−1 at 12:00 pm (1.35 sun). The composite membranes demonstrated self-floating on the air–water interface and minimal accumulation of superficial salt during the desalination process due to the hydrophobic character of EC. For concentrated saline water (21 wt% NaCl), the composite membranes maintained a relatively high evaporation rate of up to ~79 % compared to the freshwater evaporation rate. The composite membranes are robust due to the thermomechanical stability of the polymer even while operating under steam-generating conditions. Over repeated use, they exhibited excellent reusability with a relative water mass change of >90 % compared to the first evaporation cycle. Moreover, desalination of artificial seawater produced a lower cation concentration (~3–5 orders of magnitude) and thereby yielded potable water, indicating the potential for solar-driven freshwater generation.

Mapping the impacts of the anthropogenic activities and seawater intrusion on the shallow coastal aquifer of Port Said, Egypt

The quality and quantity of groundwater resources have been continuously deteriorating as a result of anthropogenic activities and their excessive usage. This has intensified seawater intrusion, particularly in the coastal area of Egypt. The management of this issue and preventing ongoing groundwater contamination are crucial responsibilities. Thus, an integrated strategy using remote sensing, geophysical technique, and hydrogeochemical analysis is used in this work to identify the causes of degradation and evaluate their impacts on the groundwater quality in East Port Said, Egypt. The following points were identified: 1) Remote sensing analysis between 1984 and 2015 showed an increase in anthropogenic activities, such as the construction of fish farms and vegetation, which became their areas of 12.5 and 37.8 km2 respectively. 2) Field observations demonstrated that the groundwater resources are being overexploited and it is expected that these human activities could have an impact on the groundwater quality. 3) The results of the resistivity approach indicated that sand and clay constitute the underlying layers and the shallow subsurface strata contain a high concentration of saline water. As a result, the aquifer is vulnerable to seawater intrusion due to its homogeneity. 4) Nineteen samples of groundwater were collected from the shallow Quaternary aquifer and the hydrochemical characteristic of the samples was identified. The hydrochemical analysis showed that the groundwater across the research area is of the Na-Cl water type and is highly saline (from 7,558 to 23,218 mg/L). By integrating the aforementioned techniques, it is evident that the research region is affected by anthropogenic activities as well as seawater intrusion on groundwater quality. These results serve as a solid base for further research on groundwater-surface water interactions and the evaluation of possible sources of contamination in the shallow aquifers under stress from anthropogenic activity in such environments.

Optimisation of Reverse-Osmosis Water Purification Plant Powered by Hydro-Generators at the Dead Sea

With the Jordan River as its main tributary, the Dead Sea is a hyper-saline lake, which was formed around 140 centuries ago. Climate change used to be the principal driver of water level changes. However, anthropogenic activities have recently emerged as a prominent source of excessive depletion. This study provides a realistic strategy for desalinating the Red Sea water whilst generating electrical power for the Dead Sea conveyance project. Seawater from the Gulf of Aqaba is transformed into highly concentrated saline water flowing to the Dead Sea whilst delivering purified drinking water to nearby regions using reverse osmosis plants. Being an energy-intensive process, a series of hydro-generators with efficient energy recovery devices will minimise the running cost by half.

ZnO based triboelectric nanogenerator on textile platform for wearable sweat sensing application

Here we report the fabrication of textile based wearable sweat sensor working under the principle of triboelectrification. Single electrode triboelectric nanogenerator (STENG) composed of chemically grown zinc oxide (ZnO) nanorods on textile platform has been explored for sweat sensing application. It has been found that the STENG can be operated through biomechanical movements to work as motion sensor. Again, the incremental nature of the output of the STENG under the variation in saline water concentration, signifies the applicability of the same as sweat sensor. It has been proposed that the attachment of hydrated Cl ions of saline water upon attachment with the physisorbed water molecule of ZnO, increases the conduction band electron in ZnO. Consequently, the amount of charge transfer between ZnO and counter triboelectric layer increases and thus yields higher output voltage. To find the efficacy of the system for practical sweat sensing application, miniaturized proof of concept prototype of the STENG (∼ 1 cm diameter) has been developed and is found to be efficient in sweating condition upon attaching to human body. The fabricated prototype is found to exhibit a sensitivity of ∼ 0.02 V/µL, along with a detection limit of ∼ 4.8 µL. Further, upon attaching the prototypes of motion sensor and sweat sensor to a shoe insole, the detection of sweat under foot movement has been demonstrated. Finally, the remote sensing of the signals generated by the textile based STENG has been demonstrated upon integrating it to a microcontroller unit and transmitting the output wirelessly to an electronic gadget.

Effect of Foliar Application of Nano-selenium on the Anatomical Characteristics of Date Palm Phoenix dactylifera L. Barhi Cultivar under Salt Stress

This study investigated the effect of salinity on the anatomical features of date palm (Phoenix dactylifera L.) and the potential roles of nano selenium (Se NPs) in alleviating the adverse effects of salinity. Two concentrations (80 and 160 mg.L-1) of SeNPs were applied as a foliar spray on date palms irrigated with different concentrations of saline water (2.5 [control], 5, 10 and 20 ds.m-1). Results showed that 5 ds.m-1 salinity had no significant effect on the anatomical structure of date palm, whether applied alone or in combination with foliar spray of Se NPs. However, the vascular bundle dimensions and thickness of the xylem, phloem and mesophyll were significantly higher in plants exposed to 10 ds.m-1 salinity compared with the control plants. In particular, foliar spray of SeNPs at 80 mg.L-1 concentration enhanced the effect on these plants. By contrast, 20 ds.m-1 salinity significantly reduced all studied parameters except for the thickness of the upper and lower cuticle, which increased. Se NPs at 80 mg.L-1 concentration had a significant effect in alleviating the adverse effects of salinity at high levels. The results of this study proved that SeNPs at 80 mg.L-1 concentration were more effective in alleviating the adverse effects of salinity on the anatomical structure of date palm leaves than 160 mg.L-1 concentration.

Exogenous γ-Aminobutyric Acid (GABA) Application Mitigates Salinity Stress in Maize Plants.

The effect of γ-Aminobutyrate (GABA) on maize seedlings under saline stress conditions has not been well tested in previous literature. Maize seedlings were subjected to two saline water concentrations (50 and 100 mM NaCl), with distilled water as the control. Maize seedlings under saline and control conditions were sprayed with GABA at two concentrations (0.5 and 1 mM). Our results indicated that GABA application (1 mM) significantly enhanced plant growth parameters (fresh shoots and fresh roots by 80.43% and 47.13%, respectively) and leaf pigments (chlorophyll a, b, and total chlorophyll by 22.88%, 56.80%, and 36.21%, respectively) compared to untreated seedlings under the highest saline level. Additionally, under 100 mM NaCl, methylglyoxal (MG), malondialdehyde (MDA), and hydrogen peroxidase (H2O2) were reduced by 1 mM GABA application by 43.66%, 33.40%, and 35.98%, respectively. Moreover, maize seedlings that were treated with 1 mM GABA contained a lower Na content (22.04%) and a higher K content (60.06%), compared to the control under 100 mM NaCl. Peroxidase, catalase, ascorbate peroxidase, and superoxide dismutase activities were improved (24.62%, 15.98%, 62.13%, and 70.07%, respectively) by the highest GABA rate, under the highest stress level. Seedlings treated with GABA under saline conditions showed higher levels of expression of the potassium transporter protein (ZmHKT1) gene, and lower expression of the ZmSOS1 and ZmNHX1 genes, compared to untreated seedlings. In conclusion, GABA application as a foliar treatment could be a promising strategy to mitigate salinity stress in maize plants.

Effect of Biostimulant Application on Plant Growth, Chlorophylls and Hydrophilic Antioxidant Activity of Spinach (Spinacia oleracea L.) Grown under Saline Stress

Irrigated agricultural lands are prone to salinity problems which may imperil horticultural crops by reducing growth, yield and even qualitative traits. Eco-friendly approaches such as biostimulant application and in particular protein hydrolysates from vegetal origin are implemented to mitigate salinity stress effects on crops. For this reason, a greenhouse experiment on spinach irrigated with increasing concentrations of saline water (EC = 3 dS m−1 (EC3), 6 dS m−1 (EC6) and 9 dS m−1 (EC9), in addition to non-saline treatment (EC0)) was organized, while plants were subjected to foliar applications of a protein hydrolysate from vegetal origin on a weekly basis. The application of this biostimulant helped mitigate the adverse effects of saline stress, by increasing the SPAD index and total chlorophylls of spinach plants. Yield was significantly boosted under biostimulant treatment in saline conditions and reached the value obtained in control treatment (no biostimulants added) × EC0 in the case of EC 3 and 6 dS m−1. In addition, the number of leaves and plants m−1 was increased under biostimulant treatment, and most importantly the hydrophilic antioxidant activity of spinach, thus a qualitative aspect of great importance was also increased. Such results increase the knowledge on the effects of protein hydrolysates application on an important leafy vegetable and may help growers mitigate saline conditions and maintain high crop yield and high quality of the final product when no other source of irrigation water is available.

Drinking behaviour of llamas (Lama glama) in choice tests for fresh or saline water

In the native region of South American camelids (SAC), the High Andes, llamas (Lama glama) face the dual confrontation with seasonal water scarcity and the risk of water salinization. The present aims are to provide more insight into drinking behaviour of llamas and their behavioural strategies in discriminating and selecting different concentrations of saline water in choice tests. Twelve adult non-pregnant female llamas with an average initial body weight of 140 kg ± 20.6 kg were kept under controlled conditions in individual pens. After a control phase (1 week) providing only fresh water, two choice tests were consecutively conducted: (1) a pairwise preference test (3 weeks) offering the choice between one bucket with fresh water and another with stepwise increasing NaCl concentration (0.25, 0.5, 0.75, 1.0, 1.25, or 1.5%) and (2) a free-choice test (3 weeks) offering six buckets simultaneously with concentrations of 0%, 0.25%, 0.5%, 0.75%, 1.0%, and 1.25% NaCl. Chopped hay, water and a mineral lick were provided for ad libitum intake. Records were kept on body weight, body condition and daily drinking water intake. Individual 24-h video recordings (23–24 per animal) were analysed for drinking duration, frequency of drinking and testing, the latter being defined as drinking lasting maximum three seconds. Body weight and body condition remained constant. Overall, a low drinking frequency was observed, indicating an adaption to water scarcity. During the control phase, the pairwise preference and the free-choice test, the daily drinking duration (p = 0.019) and frequency (p < 0.001) increased significantly averaging 162, 238 and 263 s, and 3.71–5.17 and 7.60 bouts, respectively. Similarly, the testing-to-drinking frequency ratio increased (p < 0.05) averaging 0.26, 0.35, 0.79 in phase 1, 2 and 3. Most drinking bouts occurred during the daytime (83% of drinking bouts) and followed a biphasic rhythm with peaks in the morning and the evening. Llamas showed a remarkable tolerance of saline drinking water, similar to goats. Furthermore, llamas demonstrated their capacity for behavioural adaptation when more choice options were offered by changing their drinking pattern, while maintaining their diurnal rhythm of water intake. Decision-making was based on testing of solutions which increased considerably when more choice options were offered in the free choice test. Nevertheless, the llamas maintained a high intake of saline water. The low drinking frequency of the llamas might hamper their memory formation and discrimination learning when more than two samples are offered simultaneously.

Long-term saline water irrigation decreased soil organic carbon and inorganic carbon contents

Soil carbon is a key component of ecosystem functions and is crucial to global climate conservation and crop productivity. Saline water irrigation can maintain crop yield inmost world regions of freshwater shortage. However, saline water irrigation may also induce soil salt accumulation, which would result in the change of soil physical or chemical properties. Saline water irrigation’s effect on soil organic carbon (SOC) and soil inorganic carbon (SIC) contents is of little concern. In this study, we irrigated soil with 1 g L−1, 4 g L−1 and 8 g L−1 saline water in a winter-wheat and summer-maize rotation system. After 14 years of irrigation, we sampled soils in a winter wheat and summer maize rotation system, and analyzed soil water, soil salt, SOC, and SIC contents. The results showed that, compared with 1 g L−1 water irrigation, 8 g L−1 saline water irrigation significantly increased soil water and salt contents. Moreover, 8 g L−1 saline water irrigation significantly decreased SOC and SIC contents in the 0–20 cm soil layer (p < 0.05) and mainly decreased SOC content in > 1 mm aggregates and wheat-derived SOC content in bulk soil. In comparison, 4 g L−1 saline water had no significant effect on soil water, soil salt, SOC, and SIC contents. These results indicated that a high concentration of saline water irrigation is harmful for soil carbon sequestration, while a low concentration of saline water did not affect soil carbon sequestration. Thus, using no more than 4 g L−1 saline water irrigation for 14 years can maintain soil carbon storage in the water shortage areas.

In-situ construction of water capture layer through reaction enhanced surface segregation for pervaporation desalination

Membranes with dense water capture layer and porous support layer hold great promise for achieving high flux in pervaporation desalination. Such membranes are usually fabricated by two-step methods, which often suffer from poor interfacial compatibility and membrane pore blockage. Herein, we fabricated a hetero-structured membrane with a dense water capture layer and a porous support layer in one step by reaction enhanced surface segregation (RESS) method. During the fabrication of polyether sulfone (PES) support layer via non-solvent induced phase separation (NIPS) process, the amphiphilic copolymer F127 in the casting solution and tannic acid (TA) in the coagulation bath migrated and reacted rapidly to each other, in-situ forming a TA-F127 water capture layer. The composition and structure of the water capture layer were tuned by controlling F127 content, TA concentration and reaction time. The optimal flux of 49.04 kg m−2 h−1 with the rejection of 99.99% was realized when treating 3.5 wt% NaCl solution at 70 °C. The membrane showed great adaptability for treating different concentrations of saline water. This study may provide a facile and scalable method for fabricating hetero-structured membranes toward efficient desalination.

Review: Brine Solution: Current Status, Future Management and Technology Development

Desalination brine is extremely concentrated saline water; it contains various salts, nutrients, heavy metals, organic contaminants, and microbial contaminants. Conventional disposal of desalination brine has negative impacts on natural and marine ecosystems that increase the levels of toxicity and salinity. These issues demand the development of brine management technologies that can lead to zero liquid discharge. Brine management can be productive by adopting economically feasible methodologies, which enables the recovery of valuable resources like freshwater, minerals, and energy. This review focuses on the recent advances in brine management using various membrane/thermal-based technologies and their applicability in water, mineral, and energy recoveries, considering their pros and cons. This review also exemplifies the hybrid processes for metal recovery and zero liquid discharge that may be adopted, so far, as an appropriate futuristic strategy. The data analyzed and outlook presented in this review could definitely contribute to the development of economically achievable future strategies for sustainable brine management.

Fabric-based all-weather-available photo-electro-thermal steam generator with high evaporation rate and salt resistance

Solar-driven steam generation is a practical strategy to harness solar energy for desalination and production of clean water with a minimized carbon footprint. However, this strategy suffers from a low evaporation rate under weak illumination on cloudy days or at night. Herein, we present a fabric-based all-weather-available photo-electrothermal steam generator (P/ET-SG) capable of regulating the surface temperature and evaporation rate by the coupling effect of photo-thermal and electro-thermal heating depending on the light conditions. An unprecedented high surface temperature of 52°C in the wet state and an evaporation rate of 2.61 kg m−2 h−1 were achieved by the P/ET-SG under 1 sun with only 1 V input voltage owing to the uniform heat distribution and the coupled electro-thermal source. The oneway fluidic design of the P/ET-SG effectively prevented salt precipitation during continuous desalination in 24 h and was able to remove salt granules from the evaporation surface. Furthermore, the P/ET-SG demonstrated a high evaporation rate of 2.58 kg m−2 h−1 in the purification of concentrated saline water and dye-contaminated water with high efficiency (>99.9%). This study offers new thoughts for the design of all-weather-available solar steam generators with high efficiency and makes a step forward towards fast purification of concentrated saline water and wastewater.