Applied Water Science最新文献

Reference evapotranspiration, which includes the contribution of climatic conditions in potential evapotranspiration, is considered as an important and strategic criterion in water resources management and irrigation designs. Therefore, it is necessary to determine and predict its changes in each region. In this study, using copula functions, the behavior and changes of this component were investigated in the west of Iran. For this purpose, the meteorological information of nine synoptic stations including Tmax, Tmin, WS, Rs, RHmax, and RHmin were used. This research aims to explore multivariate simulation based on vine tree sequences. Among these parameters, wind speed had the least effect on ET₀, and in all the studied stations, there was the highest correlation between ET₀-Tmax pair variable, which was equal to 0.90, 0.87, 0.89, 0.88, 0.86, 0.85, 0.88, and 0.81 in Aligudarz, Azna, Borujerd, Dorud, Khorramabad, Kuhdasht, Nurabad, and Poldakhter stations, respectively, based on Kendall's Tau statistics. The tree sequence of vine copulas including C-, D-, and R-vine was examined according to the input variables based on AIC and logarithm of likelihood evaluation criteria. According to the results, it was found that based on the evaluation criteria, the D-vine tree sequence has the best performance in the joint probability analysis of the studied variables. In addition, the results showed that the D-vine tree sequence, unlike the two R and C type sequences, has maintained the correlation between the studied pair variables until the last tree. The results of this study showed that copula functions could analyze evapotranspiration in different climates with high capability, which can be used in predicting the behavior of non-linear variables.

The current study investigated the degradation of the antibiotic metronidazole (MNZ) from aqueous solutions by means of a photo-Fenton-like process-based system. The efficiency of each variable such as CuCOFe₂O₄@AC nanoparticles (CFC), UV, and H₂O₂, along with their combined processes, was evaluated to select the most appropriate integrated process. In the second stage, a toxicity test was conducted to assess the drug residues in the effluent from the process. The toxicity test was conducted using the penetration method in Mueller-Hinton agar medium by inoculating wells and blank disks impregnated with the treated wastewater samples and control samples. The removal efficiencies of MNZ for UV, H₂O₂, CFC, UV + H₂O₂, CFC + H₂O₂, and UV + CFC + H₂O₂ processes were 2.28, 2.35%, 22.76, 7.53, 34.32, and 24.04%, respectively. As a result, the Fenton-like process (CFC + H₂O₂) was identified as the most effective method. Under test conditions: pH equal to 5, hydrogen peroxide value 1000 mg/L, CFC dosage 1000 mg/L, initial MNZ content 10 mg/L, and contact time 70 min, 67.5% of the antibiotic was removed. It was found that the effluent pharmaceutical residues were non-toxic to Escherichia coli and Enterococcus faecalis bacteria. The kinetic studies for the Fenton-like process indicated that the second-order model best fitted the achieved results. Moreover, synergistic effect in the combination process was 1.86 times greater than that of the individual processes. Also, the process demonstrated favorable efficiency in removing MNZ from aqueous solutions. Since the treated wastewater is non-toxic and the nanoparticles can be magnetically recovered, this method appears to be a promising solution for the pharmaceutical industry.

In arid and semi-arid regions, water scarcity is a dominant problem where water insufficiency greatly hinders sustainable agricultural development. Another significant challenge is usage of pump stations for lifting irrigation water to elevated lands considering cost recovery of cultivated crops. Egypt, which is a semi-arid region, has been facing challenges due to limited water resources and insufficient agricultural production. Egyptian Government seeks to expand agricultural projects to increase production. This paper focuses on expansion project along command area of El Nasr Canal, as a case study, which is supplied from El Nubaria Canal through a cascade of five pump stations irrigating new reclaimed land in north-west Egypt Delta. The main goal of this study is to analyze cost–benefit of lifting water to irrigate different crops along El Nasr Canal. The study also aims to assess sufficiency of lifting water along each pumping station and investigate shortages/surpluses until delivering water to end users. Modern irrigation is applied to only 57% of El Nasr Canal area, while surface irrigation is used in remaining areas. Cost analysis showed that total cost of lifting water for each pump station is (2.794, 5.591, 8.247, 12.138, and 17.044) × 10^–3 $/m³, respectively. Feasibility analysis indicated that sunflower, groundnuts, sugar beet, apples, and mandarins are non-feasible for most pumping stations zones even with usage of modern irrigation. Results showed irrigation demand requirements exceeded water supply causing severe shortages of 883.30 MCM/year. Accordingly, the study presented different scenarios to provide decision-makers with solutions for better management of water and cropping pattern. Methodology developed in this study presents a useful guide to analyze and assess water resources and agricultural sustainability in similar regions.

Geogenic contamination of fluoride severely impacts groundwater quality rather than industrial contamination. In this study, MODFLOW and MT3D applications are used to predict the groundwater flow and fluoride transport in Vaniyambadi and Ambur taluk in Tirupathur district. The conceptual model with three-layered aquifer system has been developed using visual MODFLOW flex v6.1 for an area of 955 km², with each grid cell sized 1000 m × 1000 m (51 rows × 49 columns). The model was calibrated from 2021 to 2022 for 30 -day period. Calibration of groundwater flow simulation after 365 days indicates that R² value was 0.98; SEE, RMSE and NRMSE were 3.72 m, 27.87 m and 6.33%, respectively. MT3D simulation reveals that the value of R² was 0.97, and RMSE and NRMSE were 0.23 m and 7.41%, respectively. The calculated fluoride concentration ranges between 0.3 and 3.49 mg/L; after 20 years of prediction, it was found to be 0.35–2.69 mg/L. The source of fluoride contamination is charnockite and granite-gneiss complex rock in Yelagiri Hill, which has 4 mg/L; after 20 years of simulation, the concentration was 9.91 mg/L and the plume extends up to 8 km towards the Palar River basin. Furthermore, HHRA has been used to evaluate the impact of fluoride on adults and children. According to the HHRA, hazard index (HI) was found to be more than one in many locations, causing serious health hazard. The results of these findings pave the way for further research on prevention of groundwater pollution due to geogenic migration.

In this study, the inactivation of various bacterial strains in a solar illuminated photocatalysis reactor with a titania photocatalyst dispersed in a geopolymer coating is studied. The modular reactor design consists of connected catalyst-coated open water carrying chutes. The cleaning efficiency of the process against chemical and biological water contaminants was evaluated by means of test series with methylene blue as a reference for chemical contamination and by studying the inactivation of the strains Escherichia coli, Bacillus subtilis, Pseudomonas fluorescens and an undefined mixed culture from the effluent of the secondary clarifier of a wastewater treatment plant as biological contaminants. Test series with methylene blue showed reduction efficiencies of 17–63% for non-catalyst-coated reference reactors and 55–99% for catalyst-coated reactors within 120–300 min of exposure to natural sunlight. Disinfection test series showed reduction efficiencies of 0.0–2.8 log units (without catalyst) and 0.0–4.4 log units (with catalyst) for mentioned bacteria and the mixed culture within 40–180 min of light exposure. Hence, the catalyst-coated system consistently showed a significantly higher degradation efficiency than the non-coated reference. A comparison of methylene blue degradation under natural solar irradiation and artificial UVA irradiation conditions showed that this simple reactor concept is suitable for the combined elimination of trace substances and disinfection of water even at moderate flux rates of 1000 W/m².

Utilizing aquifers as groundwater storage reservoirs is an effective strategy for water management in water scare regions. The success of managed aquifer recharge (MAR) relies on the assessment and modeling of site-specific hydrogeological characteristics, including groundwater salinity, transmissivity, storativity, slope, soil properties, proximity to water recharge networks and road accessibility, etc. This study employs a GIS-based multi-criteria evaluation technique, integrating both ground and remote sensing datasets. The results indicate that a significant portion of the total land area, approximately 7,414.11 km² (64%), can potentially be utilized for MAR practices, while the remaining 36% is restricted due to various constraints, such as built-up areas, roads, agricultural lands and nationally protected areas for conservation. The available 64% of land is further categorized into subclasses ranging from highly suitable to least suitable areas. Most of the highly and moderately suitable regions are located in the northern central parts of the country where seasonal surplus treated wastewater and desalinated water may be used to recharge groundwater. Furthermore, MAR technology can also be used to tackle saltwater intrusion in the coastal areas by injecting seasonal surplus desalinated and treated wastewater. These findings suggest that MAR technology has a high potential to facilitate aquifer water storage and recovery in the country, which can contribute to sustainable water resources.

Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow-On (GRACE-FO) are being increasingly used as valuable data sources for hydrological monitoring. However, their coarse spatial resolution is considered as a limitation for regional studies, especially in areas with remarkable hydroclimate variability. In this study, a novel approach is presented for downscaling, and gap filling of terrestrial water storage (TWS) in Tehran province, Iran. Non-stationarity in the GRACE/GRACE-FO derived TWS is a significant challenge for predictive models. In this regard, the Hodrick–Prescott filter was adopted to detrend the TWS data. Afterward, several machine learning and deep learning techniques are employed for TWS prediction using Global Land Data Assimilation System and the fifth-generation ECMWF reanalysis (ERA5) datasets. The methodology is employed for bridging the gap between GRACE and GRACE-FO as well. Subsequently, the models are trained with different combinations of input variables and their performance is evaluated against the actual values. In parallel, a separate regression model based on the temporal index of the sample is developed for trend estimation and highlighting the role of anthropogenic activities. The proposed methodology is employed for bridging the gap between GRACE and GRACE-FO as well. The models with the highest accuracy are fed by input data with a spatial resolution of 0.25° × 0.25° to obtain fine-resolution TWS. Finally, the downscaled TWS derived from the predictive model is applied to calculate groundwater storage (GWS). The monthly TWS prediction results exhibit a strong correlation (CC = 0.93) and a low error (RMSE = 4.75 cm), underscoring the effectiveness of the proposed approach. TWS and GWS computations reveal rapid declines in groundwater-level prevailing by anthropogenic factors which exacerbate water crisis issues and environmental problems in the study area.

This study focuses on the preparation and characterization of cross-linked carboxymethyl cellulose (CMC) biosorbent for efficient removal of Zn²⁺ ions from aqueous solutions. The microstructural features of the biosorbent were examined using scanning electron microscopy (SEM), while elemental analysis was conducted using an elemental analyzer to determine carbon (C), hydrogen (H), nitrogen (N), and sulfur (S) content. Fourier transform infrared (FTIR) spectroscopy was employed to identify functional groups within the biosorbent. Sorption experiments revealed that increasing the biosorbent dose led to higher Zn²⁺ removal rates until equilibrium was reached. The optimal pH for Zn²⁺ removal was determined to be ≥ 5, attributed to the conversion of acetate group to its ionic form. Rapid kinetics were observed, with 99% removal achieved within 5 min. The biosorbent exhibited a maximum sorption capacity of 10.809 mg/g and a removal rate of 99% at pH 5. Desorption studies demonstrated efficient Zn²⁺ recovery using 0.25 M HCl solution, with a total desorption rate exceeding 99%. The findings indicate the potential for cost-effective regeneration of the biosorbent using dilute acid solutions, enhancing its sustainability and practical applicability in water purification processes. Additionally, the biosorbent’s selectivity for Zn²⁺ ions over competing ions and its effectiveness in treating real water samples, including those containing Na⁺, K⁺, Ca²⁺, and Mg²⁺, highlight its suitability for practical water purification applications.

Groundwater is the main water source in arid climate regions. Climate change and extensive groundwater exploitation will stress the groundwater resources in the upcoming decades. Therefore, groundwater quantity and quality should be assessed. In this study, we focused on groundwater quantity, including recharge and storage (using groundwater level as an indicator) to predict system vulnerability. The northern portion of El-Qaa Plain was chosen as a case study because the aquifer is coastal, arid, over-exploited, and naturally replenished via seasonal precipitation events. To project groundwater recharge under climate change and future exploitation, Water and Energy Transfer between Soil, Plants, and Atmosphere under quasi-steady State (WetSpass) was applied. Modular Finite Difference Groundwater Flow Model (MODFLOW) was utilized to project the groundwater level. Future climate ensembles were acquired from Regional Climate Models (RCMs) of Coordinated Regional Downscaling Experiment (CORDEX) datasets for the EURO 11 domain. The ensembles were bias-corrected using the Delta Change Factor (DCF) method. The results indicate that groundwater resources will be severely affected by climate change, as recharge might drop by nearly 35% to 75% during 2071–2100 for moderate and severe change ensembles. The mean groundwater level might decline by around 7–8 m by 2100 for the same ensembles. Regarding over-exploitation, the maximum drawdown will rise to approximately 16 m (no change in abstraction rate), to 36 m (increase in abstraction rate), and 7 m (decrease in abstraction rate). The results might aid decision-makers and stakeholders developing sustainable water resource management plans for the area.

The objective of this study was to assess the feasibility of using a poly(vinylidene fluoride) (PVDF) membrane modified with cellulose/nanostructures as a separation technique for the removal of poly(vinyl alcohol)(PVA)/reactive dyes from synthetic textile wastewater. The goal was to recycle PVA/reactive dye yellow 145 for reuse in the industry while simultaneously reclaiming water for reuse. To achieve this, the study aimed to evaluate the influence of SnO₂/ZnO nanostructures on the polymer mixture, examining their impact on permeation and rejection of PVA/reactive dye. Additionally, the study investigated the antifouling properties of PVDF, both in the presence and absence of electrospun cellulose nanofibers. Chemical analysis techniques, including SEM, EDS, FTIR, mechanical strength testing, contact angle measurement, AFM, and determination of molecular weight cutoff (MWCO), were employed to assess the synthesized membranes. The MWCO results indicated a decrease in pore size after surface modification with electrospun cellulose acetate (CA), with the modified membrane (M2-Mod) showing a reduced MWCO of 6700 Da compared to the unmodified membrane’s MWCO of 13,980 Da. Furthermore, the study aimed to identify the optimal polymeric nanocomposite of PVDF with nano-SnO₂ or ZnO, along with electrospun cellulose nanofibers, to enhance %PVA and %dye rejection while improving membrane productivity and fouling resistance. The formulation containing a mixture of SnO₂ and ZnO, in the presence of electrospun CA, demonstrated superior performance, achieving 98% PVA rejection, 95% reactive dye rejection, and a stable flux of 20 LMH, with a normalized flux of 92%. Overall, it can be concluded that the optimized modified membrane formulation (M2-Mod) exhibited excellent antifouling behavior, holding significant potential for promoting circular economy and sustainability in textile wastewater treatment.