Water

15 pages, 3359 KiB

Open AccessArticle

Novel Design of Double Slope Solar Distiller with Prismatic Absorber Basin, Linen Wicks, and Dual Parallel Spraying Nozzles: Experimental Investigation and Energic–Exergic-Economic Analyses

by Mohamed E. Zayed, Abdallah Kamal, Mohamed Ragab Diab, Fadl A. Essa, Otto L. Muskens, Manabu Fujii and Ammar H. Elsheikh

Water 2023, 15(3), 610; https://doi.org/10.3390/w15030610 - 3 Feb 2023

Cited by 52 | Viewed by 3745

Abstract

Increasing the evaporation zone inside the solar distiller (SD) is a pivotal method for augmenting its freshwater production. Hence, in this work, a newly designed prismatic absorber basin covered by linen wicks was utilized instead of the conventional flat absorber basin to increase [...] Read more.

Increasing the evaporation zone inside the solar distiller (SD) is a pivotal method for augmenting its freshwater production. Hence, in this work, a newly designed prismatic absorber basin covered by linen wicks was utilized instead of the conventional flat absorber basin to increase the surface area of the vaporization zone in a double-slope solar distiller (DSSD). Meanwhile, for further enhancement of modified DSSD performance, dual parallel spraying nozzles are incorporated underneath the glass cover as a saltwater feed supply to minimize the thickness of the saltwater film on the wick, which enhances the heating process of the wick surface and, consequently, the evaporation and condensation processes are improved. Two double slope distillers, namely a double slope solar distiller with wick prismatic basin and dual parallel spraying nozzles (DSSD-WPB&DPSN) and a traditional double slope solar distiller (TDSSD), are made and tested in the outdoor summer conditions of Tanta, Egypt (31° E and 30.5° N). A comparative energic–exergic-economic analysis of the two proposed solar stills is also conducted, in terms of the cumulative distillation yield, daily energy efficiency, daily exergy efficiency, and cost per liter of distilled yield. The present results show that the cumulative distillation yield of the DSSD-WPB&DPSN was 8.20 kg/m²·day, which is higher than that of the TDSSD by 49.64%. Furthermore, the energy and exergy efficiencies were increased by 48.51% and 118.10%, respectively, relative to TDSSD. Additionally, the life cost assessment reveals that the cost per liter of the distilled yield of the DSSD-WPB&DPSN is decreased by 11.13% compared to the TDSSD. Full article

(This article belongs to the Special Issue Advanced Technology for Desalination and Water Purification)

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13 pages, 5248 KiB

Open AccessArticle

Effect of Rotational Speed on Pressure Pulsation Characteristics of Variable-Speed Pump Turbine Unit in Turbine Mode

by Linmin Shang, Jingwei Cao, Xin Jia, Shengrui Yang, Sainan Li, Lei Wang, Zhengwei Wang and Xiaobing Liu

Water 2023, 15(3), 609; https://doi.org/10.3390/w15030609 - 3 Feb 2023

Cited by 11 | Viewed by 2815

Abstract

The pumped storage power station plays a vital role in modern power systems, where the key component is the pump turbine. Variable-speed operation can improve the operating efficiency of the pump turbine and increase the operating efficiency under turbine operating conditions and the [...] Read more.

The pumped storage power station plays a vital role in modern power systems, where the key component is the pump turbine. Variable-speed operation can improve the operating efficiency of the pump turbine and increase the operating efficiency under turbine operating conditions and the automatic frequency regulation capability under pump operating conditions, thus obtaining higher efficiency and better stability. However, its operation characteristics are different from many conventional pumped storage units, which makes the study of variable-speed pump turbines more difficult. Therefore, in this paper, 10 representative pressure monitoring points are selected in the model to compare and study the flow characteristics and pressure pulsation characteristics of a variable-speed pump turbine at three speeds (N1-398.57 m/s, N2-412.16 m/s, and N3-428.6 m/s). According to our results, it is shown that the maximum pressure and pressure pulsation are small at low rotational speeds, which means that the unit will maintain better stability during the reduction in rotational speed and reducing the speed will not affect the safety and stability of the equipment. The purpose of this paper is to provide guidance for the safe operation of the unit and to improve the effect of speed in terms of dynamic behavior of variable-speed water pump turbine units. Meanwhile, this study will lay the groundwork for the optimal design of variable-speed pump turbines. Full article

(This article belongs to the Special Issue Advancements in the Complex Vortex Flow in Hydraulic Machinery)

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13 pages, 3383 KiB

Open AccessArticle

Nitrogen-Doped Core-Shell Mesoporous Carbonaceous Nanospheres for Effective Removal of Fluorine in Capacitive Deionization

by Yubo Zhao, Kexun Li, Bangsong Sheng, Feiyong Chen and Yang Song

Water 2023, 15(3), 608; https://doi.org/10.3390/w15030608 - 3 Feb 2023

Cited by 3 | Viewed by 2320

Abstract

Fluorine pollution of wastewater is a global environmental problem. Capacitive deionization has unique advantages in the defluorination of fluorine-containing wastewater; however, the low electrosorption capacity significantly restricts its further development. To overcome this limitation, nitrogen-doped core-shell mesoporous carbonaceous nanospheres (NMCS) were developed in [...] Read more.

Fluorine pollution of wastewater is a global environmental problem. Capacitive deionization has unique advantages in the defluorination of fluorine-containing wastewater; however, the low electrosorption capacity significantly restricts its further development. To overcome this limitation, nitrogen-doped core-shell mesoporous carbonaceous nanospheres (NMCS) were developed in this study based on structural optimization and polarity enhancement engineering. The maximal electrosorption capacity of NMCS for fluorine reached 13.34 mg g⁻¹, which was 24% higher than that of the undoped counterpart. NMCS also indicated excellent repeatability evidenced by little decrease of electrosorption capacity after 10 adsorption-regeneration cycles. According to material and electrochemical measurements, the doping of nitrogen into NMCS resulted in the improvement of physicochemical properties such as conductivity and wettability, the amelioration of pore structure and the transformation of morphology from yolk-shell to core-shell structure. It not only facilitated ion transportation but also improved the available adsorption sites, and thus led to enhancement of the defluorination performance of NMCS. The above results demonstrated that NMCS would be an excellent electrode material for high-capacity defluorination in CDI systems. Full article

(This article belongs to the Special Issue Adsorption Technology for Water and Wastewater Treatments)

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19 pages, 4624 KiB

Open AccessArticle

Data Integration for Investigating Drivers of Water Quality Variability in the Banja Reservoir Watershed

by Erica Matta, Mariano Bresciani, Giulio Tellina, Karin Schenk, Philipp Bauer, Fabian Von Trentini, Nils Ruther and Alena Bartosova

Water 2023, 15(3), 607; https://doi.org/10.3390/w15030607 - 3 Feb 2023

Cited by 4 | Viewed by 2184

Abstract

It is increasingly important to know the water quality of a reservoir, given the prospect of an environment poor in water reserves, which are based on intense and short-lived precipitation events. In this work, vegetation indices (NDVI, EVI) and bio-physical parameters of the [...] Read more.

It is increasingly important to know the water quality of a reservoir, given the prospect of an environment poor in water reserves, which are based on intense and short-lived precipitation events. In this work, vegetation indices (NDVI, EVI) and bio-physical parameters of the vegetation (LAI, FC), meteorological variables, and hydrological data are considered as possible drivers of the spatial and temporal variability of water quality (WQ) of the Banja reservoir (Albania). Sentinel-2 and Landsat 8/9 images are analyzed to derive WQ parameters and vegetation properties, while the HYPE model provides hydrological variables. Timeseries of the considered variables are examined using graphical and statistical methods and correlations among the variables are computed for a five-year period (2016–2022). The added-value of integrating earth observation derived data is demonstrated in the analysis of specific time periods or precipitation events. Significant positive correlations are found between water turbidity and hydrological parameters such as river discharge or runoff (0.55 and 0.40, respectively), while negative correlations are found between water turbidity and vegetation descriptors (−0.48 to −0.56). The possibility of having easy-to-use tools (e.g., web portal) for the analysis of multi-source data in an interactive way, facilitates the planning of hydroelectric plants management operations. Full article

(This article belongs to the Topic Remote Sensing in Water Resources Management Models)

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26 pages, 21280 KiB

Open AccessArticle

Climate Change Impacts on Water Resources in Arid and Semi-Arid Regions: A Case Study in Saudi Arabia

by Mustafa El-Rawy, Okke Batelaan, Nassir Al-Arifi, Ali Alotaibi, Fathy Abdalla and Mohamed Elsayed Gabr

Water 2023, 15(3), 606; https://doi.org/10.3390/w15030606 - 3 Feb 2023

Cited by 31 | Viewed by 7006

Abstract

In the coming years, climate change is predicted to impact irrigation water demand considerably, particularly in semi-arid regions. The aim of this research is to investigate the expected adverse impacts of climate change on water irrigation management in Saudi Arabia. We focus on [...] Read more.

In the coming years, climate change is predicted to impact irrigation water demand considerably, particularly in semi-arid regions. The aim of this research is to investigate the expected adverse impacts of climate change on water irrigation management in Saudi Arabia. We focus on the influence of climate change on irrigation water requirements in the Al Quassim (97,408 ha) region. Different climate models were used for the intermediate emission SSP2-4.5 and the high emission SSP5-8.5 Coupled Model Intercomparison Project Phase 6 (CMIP6) scenarios. The FAO-CROPWAT 8.0 model was used to calculate reference evapotranspiration (ETo) using weather data from 13 stations from 1991 to 2020 and for both the SSP2-4.5 and SSP5-8.5 scenarios for the 2040s, 2060s, 2080s, and 2100s. The findings indicated that, for the 2100s, the SSP2-4.5 and SSP5-8.5 scenarios forecast annual average ETo increases of 0.35 mm/d (6%) and 0.7 mm/d (12.0%), respectively. Net irrigation water requirement (NIWR) and growth of irrigation water requirement (GIWR) for the main crops in the Al Quassim region were assessed for the current, SSP2-4.5, and SSP5-8.5 scenarios. For SSP5-8.5, the GIWR for the 2040s, 2060s, 2080s, and 2100s are expected to increase by 2.7, 6.5, 8.5, and 12.4%, respectively, compared to the current scenario (1584.7 million m³). As a result, there will be higher deficits in 2100 under SSP5-8.5 for major crops, with deficits of 15.1%, 10.7%, 8.3%, 13.9%, and 10.7% in the crop areas of wheat, clover, maize, other vegetables, and dates, respectively. Optimal irrigation planning, crop pattern selection, and modern irrigation technologies, combined with the proposed NIWR values, can support water resources management. The findings can assist managers and policymakers in better identifying adaptation strategies for areas with similar climates. Full article

(This article belongs to the Section Water Resources Management, Policy and Governance)

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23 pages, 15021 KiB

Open AccessArticle

Credal-Decision-Tree-Based Ensembles for Spatial Prediction of Landslides

by Jingyun Gui, Ignacio Pérez-Rey, Miao Yao, Fasuo Zhao and Wei Chen

Water 2023, 15(3), 605; https://doi.org/10.3390/w15030605 - 3 Feb 2023

Cited by 4 | Viewed by 3071

Abstract

Spatial landslide susceptibility assessment is a fundamental part of landslide risk management and land-use planning. The main objective of this study is to apply the Credal Decision Tree (CDT), adaptive boosting Credal Decision Tree (AdaCDT), and random subspace Credal Decision Tree (RSCDT) models [...] Read more.

Spatial landslide susceptibility assessment is a fundamental part of landslide risk management and land-use planning. The main objective of this study is to apply the Credal Decision Tree (CDT), adaptive boosting Credal Decision Tree (AdaCDT), and random subspace Credal Decision Tree (RSCDT) models to construct landslide susceptibility maps in Zhashui County, China. The observed 169 historical landslides were classified into two groups: 70% (118 landslides) for training and 30% (51 landslides) for validation. To compare and validate the performance of the three models, the receiver operating characteristic (ROC) curve and the area under the ROC curve (AUC) were utilized. Specifically, the success rates of the CDT model, AdaCDT model, and RSCDT model were 0.788, 0.821, and 0.847, respectively, while the corresponding prediction rates were 0.771, 0.802, and 0.861, respectively. In sum, the two ensemble models can effectively improve the performance accuracy of an individual CDT model, and the RSCDT model was proven to be superior to the other two models. Therefore, ensemble models are capable of being novel and promising approaches for the spatial prediction and zonation of a certain region’s landslide susceptibility. Full article

(This article belongs to the Section Hydrogeology)

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29 pages, 50250 KiB

Open AccessFeature PaperArticle

Investigation of Data-Driven Rating Curve (DDRC) Approach

by Biplov Bhandari, Kel Markert, Vikalp Mishra, Amanda Markert and Robert Griffin

Water 2023, 15(3), 604; https://doi.org/10.3390/w15030604 - 3 Feb 2023

Cited by 2 | Viewed by 2939

Abstract

Flooding is a recurring natural disaster worldwide; developing countries are particularly affected due to poor mitigation and management strategies. Often discharge is used to inform the flood forecast. The discharge is usually inferred from the water level via the rating curve because the [...] Read more.

Flooding is a recurring natural disaster worldwide; developing countries are particularly affected due to poor mitigation and management strategies. Often discharge is used to inform the flood forecast. The discharge is usually inferred from the water level via the rating curve because the latter is relatively easy to measure compared to the former. This research focuses on Cambodia, where data scarcity is prevalent, as in many developing countries. Thus, the rating curve has not been updated, making it difficult to effectively evaluate the performance of the global streamflow services, such as the Global Flood Awareness System (GloFAS) and Streamflow Prediction Tool (SPT), whose longer lead time can benefit the country in taking early action. In this study, we used time series of water level and discharge data to understand the changes in the flood plain to generate a data-derived rating curve for fifteen stations in Cambodia. We deployed several statistical and data-driven techniques to derive a generalized, scalable, and region-agnostic method. We further validated the process by applying it to ten stations in the US and found similar performance. In Cambodia, we obtained an average Kling Gupta Efficiency (KGE) of ∼99% & an average Relative Root Mean Squared Error (RRMSE) of 12% with an average Mean Absolute Error (MAE) of 200 m

^{3}

/s. In the US, overall KGE was 97%, with an average RRMSE of 17% and an average MAE of 32 m

^{3}

/s. The results indicated that the distribution of the dataset was key in deriving a good rating curve and that the stations with a low flow stations generally had higher errors than the high flow stations. The time series approach was shown to have more probability in capturing the high-end and low-end events compared to traditional method, where usually fewer data points are used. The study demonstrates that time series of data has valuable information to update the rating curve, especially in a data-scarce country. Full article

(This article belongs to the Section Hydrology)

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20 pages, 73793 KiB

Open AccessReview

Back to Basics: Revision of Coccolithophore Species List in the Adriatic Sea

by Jelena Godrijan, Jasna Arapov, Sanda Skejić and Mia Bužančić

Water 2023, 15(3), 603; https://doi.org/10.3390/w15030603 - 3 Feb 2023

Viewed by 2944

Abstract

Coccolithophores are unicellular marine algae belonging to the haptophyte group, characterized by the production of intricate calcium carbonate plates that adorn their cells and exhibit species-specific morphology. The Adriatic Sea has historically been the type locality of numerous phytoplankton species, including coccolithophores. However, [...] Read more.

Coccolithophores are unicellular marine algae belonging to the haptophyte group, characterized by the production of intricate calcium carbonate plates that adorn their cells and exhibit species-specific morphology. The Adriatic Sea has historically been the type locality of numerous phytoplankton species, including coccolithophores. However, since the initial description, many species have not been recorded during the frequent phytoplankton surveys in the Adriatic Sea. This was mainly because these surveys did not use electron microscopy, which is necessary for accurate species identification. In this study, we re-evaluate the coccolithophore species lists using historical records and compare them with recent surveys in the coastal and open waters of the Adriatic Sea. In light of changes in nomenclature resulting from clarification of the species’ life cycles, we update the taxonomic list of coccolithophore species occurring in the Adriatic. Full article

(This article belongs to the Special Issue Marine Phytoplankton Diversity)

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16 pages, 4634 KiB

Open AccessArticle

An Integrated Model of Pluvial Flood Risk and Adaptation Measure Evaluation in Shanghai City

by Hengzhi Hu, Hanwei Yang, Jiahong Wen, Min Zhang and Yanjuan Wu

Water 2023, 15(3), 602; https://doi.org/10.3390/w15030602 - 3 Feb 2023

Cited by 7 | Viewed by 2965

Abstract

Under climate warming, the frequency and intensity of extreme rainstorms-induced urban pluvial floods are significantly increasing, leading to severe flooding risks in megacities. An integrated model that incorporates rainfall processing, waterlogging simulation, GIS spatial analysis, risk assessment, and measure evaluation was developed, optimizing [...] Read more.

Under climate warming, the frequency and intensity of extreme rainstorms-induced urban pluvial floods are significantly increasing, leading to severe flooding risks in megacities. An integrated model that incorporates rainfall processing, waterlogging simulation, GIS spatial analysis, risk assessment, and measure evaluation was developed, optimizing both the assessment procedure and the computing efficiency for assessing pluvial flood risk and adaptation measures. The historic “9.13” extreme rainstorm event is simulated, showing excellent consistency of inundation depth and area compared to Shanghai’s “110” alarm validation records. Three extreme rainstorm scenarios, using return periods of 200a, 500a, and 1000a, were generated to evaluate the flooding risk and measures’ performance. The results show that the low-lying areas in the solution district are the most inundated region based on the existing defense measures. The maximum inundation depth of high-extreme rainstorm scenarios is up to 1.5 m, and the low-lying areas would still be above 1 m even in low-extreme scenarios. Increasing the drainage capacity can effectively reduce the total loss by 80% in the low-extreme scenario, yet still suffering a significant loss in both moderate-extreme and high-extreme scenarios. The integrated model can provide technical support for the rapid evaluation of flood control prevention capabilities. Full article

(This article belongs to the Section Oceans and Coastal Zones)

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20 pages, 7290 KiB

Open AccessArticle

Quality and Health Risk Assessment of Groundwater for Drinking and Irrigation Purpose in Semi-Arid Region of India Using Entropy Water Quality and Statistical Techniques

by Balamurugan Panneerselvam, Nagavinothini Ravichandran, Shunmuga Priya Kaliyappan, Shankar Karuppannan and Butsawan Bidorn

Water 2023, 15(3), 601; https://doi.org/10.3390/w15030601 - 3 Feb 2023

Cited by 31 | Viewed by 5095

Abstract

The continuous intake of contaminated drinking water causes serious issues for human health. In order to estimate the suitability of groundwater for drinking and irrigation, and also conduct human risk assessments of various groups of people, a total of 43 sample locations in [...] Read more.

The continuous intake of contaminated drinking water causes serious issues for human health. In order to estimate the suitability of groundwater for drinking and irrigation, and also conduct human risk assessments of various groups of people, a total of 43 sample locations in the semi-arid southern part of India were selected based on population density, and we collected and analyzed groundwater from the locations for major anions and cations. The present study’s novelty is integrating hydrochemical analysis with the entropy water quality index (EWQI), nitrate pollution index (NPI) and human health risk assessment. The results of the EWQI revealed that 44.19% of the sample locations need to be treated before consumption. About 37.20% of the study region has a high concentration of nitrate in the groundwater. NPI revealed that 41.86% of the samples had moderate or significant pollution levels. The non-carcinogenic risk evaluation showed that 6–12-year-old children are at a higher risk than teenagers, adults and elderly people in the study area. The natural sources of nitrate and other contamination of groundwater are rock–water interaction, weathering of rock, dissolution of carbonate minerals and evaporation processes, and the anthropogenic sources are the decomposition of organic substances in dumping yards, uncovered septic tanks and human and animal waste. The results suggest taking mitigation measures to reduce the contamination and improve the sustainable planning of groundwater management. Full article

(This article belongs to the Section Water Quality and Contamination)

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23 pages, 6084 KiB

Open AccessArticle

Temperature, Precipitation, and Agro-Hydro-Meteorological Indicator Based Scenarios for Decision Making in Ogallala Aquifer Region

by Aavudai Anandhi, Raveendranpillai Deepa, Amit Bhardwaj and Vasubandhu Misra

Water 2023, 15(3), 600; https://doi.org/10.3390/w15030600 - 3 Feb 2023

Cited by 2 | Viewed by 3040

Abstract

The Ogallala Aquifer is one of the most productive agricultural regions and is referred to as the “breadbasket of the world”. It covers approximately 225,000 square miles beneath the Great Plains region spanning the states of Texas, New Mexico, Oklahoma, Kansas, Nebraska, South [...] Read more.

The Ogallala Aquifer is one of the most productive agricultural regions and is referred to as the “breadbasket of the world”. It covers approximately 225,000 square miles beneath the Great Plains region spanning the states of Texas, New Mexico, Oklahoma, Kansas, Nebraska, South Dakota, Wyoming, and Colorado. The aquifer is a major water source for the region, with its use exceeding recharge. Previous studies have documented climate changes and their impacts in the region. However, this is the first study to document temperature and precipitation changes over the entire Ogallala region from 35 General Circulation Models participating in Phase 5 of the Climate Model Intercomparison Project (CMIP5). The main study objectives were (1) to provide estimates of present and future climate change scenarios for the High Plains Aquifer, (2) to translate the temperature and precipitation changes to agro-ecosystem indicator changes for Kansas using scenario funnels, and (3) to make recommendations for water resource and ecosystem managers to enable effective planning for the future availability of ecosystem services. The temperature change ranged from −4 °C to 8 °C, while the precipitation changes were between −50% to +50% over the region. This study improves the understanding of climate change on water resources and agro-ecosystems. This knowledge can be used to evaluate similar resources where the replenishment rate is slow. Full article

(This article belongs to the Section Hydrogeology)

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18 pages, 4469 KiB

Open AccessArticle

Influence of the Combined Magnetic Field and High Dilution Technology on the Intrinsic Emission of Aqueous Solutions

by Nikita V. Penkov

Water 2023, 15(3), 599; https://doi.org/10.3390/w15030599 - 3 Feb 2023

Cited by 6 | Viewed by 2868

Abstract

Liquids prepared by sequential multiple dilutions with mechanical action (highly diluted or HD solutions) are able to influence certain properties of adjacent solutions without direct contact, which is mediated by their emission in the infrared (IR) frequency range. These properties do not manifest [...] Read more.

Liquids prepared by sequential multiple dilutions with mechanical action (highly diluted or HD solutions) are able to influence certain properties of adjacent solutions without direct contact, which is mediated by their emission in the infrared (IR) frequency range. These properties do not manifest when HD solutions are prepared in a geomagnetic field-free chamber. Here we studied the influence of a magnetic field and the intensity of mechanical treatment on the intrinsic emission of HD solutions of antibodies (Ab) to IFNγ and their effect on the adjacent water. IR-emission spectra were recorded using a Fourier-transform IR spectrometer. Magnetic field treatment reduced the intrinsic emission intensity of all HD samples; non-contact incubation with HD Ab prepared with intense (iHD Ab) shaking or gentle (gHD Ab) mixing reduced the emission intensity of HD water as well. The emission intensity of intact water was affected only by iHD Ab. Pre-treatment of HD Ab with a magnetic field did not modify their non-contact effect on intact water. We confirmed the presence of a non-contact effect and determined what factors it depends on (treatment with a magnetic field and the intensity of shaking when preparing HD solutions). The intensity of water emission both in the presence of HD Ab and in the presence of a magnetic field changes in a similar way. Full article

(This article belongs to the Section New Sensors, New Technologies and Machine Learning in Water Sciences)

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22 pages, 1169 KiB

Open AccessFeature PaperArticle

Removal of Contaminants of Emerging Concern from Wastewater Using an Integrated Column System Containing Zero Valent Iron Nanoparticles

by Evridiki Barka, Constantinos Noutsopoulos, Andriani Galani, Iliana Panagou, Maria Kalli, Elena Koumaki, Simos Malamis and Daniel Mamais

Water 2023, 15(3), 598; https://doi.org/10.3390/w15030598 - 3 Feb 2023

Cited by 6 | Viewed by 3713

Abstract

Non-steroidal anti-inflammatory drugs (NSAIDs) and endocrine disruptors (EDCs) are among the most important categories of contaminants of emerging concern (CECs), and many advanced technologies have been developed for their elimination from water and wastewater, including nano-zero valent iron (nZVI). This study investigates the [...] Read more.

Non-steroidal anti-inflammatory drugs (NSAIDs) and endocrine disruptors (EDCs) are among the most important categories of contaminants of emerging concern (CECs), and many advanced technologies have been developed for their elimination from water and wastewater, including nano-zero valent iron (nZVI). This study investigates the performance of nZVI synthesized from green tea extracts and incorporated into a cationic resin (R-nFe) in the removal of four selected NSAIDs, namely ibuprofen (IBU), naproxen (NPX), diclofenac (DCF), and ketoprofen (KFN), and an EDC, namely bisphenol A (BPA). Column experiments were conducted to evaluate the effect of various operating parameters, including initial CECs concentration, contact time, pH, addition, and dose of sodium persulfate (PS). To the authors’ knowledge, this is the first time that environmentally friendly produced nZVI has been combined with PS in column experiments for the removal of CECs from wastewater. With a contact time of 2.2 min, PS = 1 mM, and influent pH = 3.5, 27–72% of IBU, 70–99% of NPX, 70–95% of DCF, 28–50% of KFN, and 61–91% of BPA were removed during a 12-day operation of the system, while the initial concentration of each substance was 5 μg/L. Therefore, it is anticipated that the proposed system could be a promising post-treatment technology for the removal of CECs from wastewater. Full article

(This article belongs to the Section Wastewater Treatment and Reuse)

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20 pages, 6118 KiB

Open AccessArticle

Evaluation of Pressure Types Impacted on Sediment Supply to Dam Reservoirs: Selected Examples of the Outer Western Carpathians Catchments Area

by Damian Absalon, Magdalena Matysik and Łukasz Pieron

Water 2023, 15(3), 597; https://doi.org/10.3390/w15030597 - 2 Feb 2023

Cited by 3 | Viewed by 2366

Abstract

The proper characteristics of the catchment area of dammed reservoirs is of great importance when managing their capacity in the context of enabling proper functioning, including retention of the planned amount of water and counteracting the effects of drought. Therefore, detailed analyses covered [...] Read more.

The proper characteristics of the catchment area of dammed reservoirs is of great importance when managing their capacity in the context of enabling proper functioning, including retention of the planned amount of water and counteracting the effects of drought. Therefore, detailed analyses covered mountain reservoirs with varying degrees of capacity changes: Goczałkowice on the Vistula, Rożnów on the Dunajec and Tresna on the Soła, thanks to which reasons for the differences in these changes were determined. For this purpose, data on the volume of the suspended load was used. Diversity in its transport is mainly caused by the presence of damming structures. Correlation of morphological and hydraulic indicators was carried out, preceded by the identification and characteristics of all transverse and longitudinal structures located in catchments upstream of individual reservoirs. Analysis of the geological structure, as well as the structure of land use in the basins of the reservoirs, was also performed. The obtained results allowed for the preparation of recommendations for further work, allowing, among other things, an increase in water retention. The key factors for maintaining the capacity of retention reservoirs were defined, which may be useful in national plans or programs in the field of counteracting the effects of drought or flood protection. Full article

(This article belongs to the Special Issue Sediment Transport, Budgets and Quality in Riverine Environments)

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29 pages, 7915 KiB

Open AccessArticle

Integration of Hydrate-Based Desalination (HBD) into Multistage Flash (MSF) Desalination as a Precursor: An Alternative Solution to Enhance MSF Performance and Distillate Production

by Pranav Thoutam, Parvin Ahmadi Sefiddashti, Faizan Ahmad, Hani Abulkhair, Iqbal Ahmed, Abdulmohsen Al-saiari, Eydhah Almatrafi, Omar Bamaga and Sina Rezaei Gomari

Water 2023, 15(3), 596; https://doi.org/10.3390/w15030596 - 2 Feb 2023

Cited by 2 | Viewed by 2357

Abstract

This study considers the integration of multistage flash (MSF) desalination with hydrate-based desalination (HBD) precursor to improve MSF performance in terms of distillate production, longevity, and operational conditions. This is accomplished by a comprehensive analysis of the rate of scale formation, distillate production, [...] Read more.

This study considers the integration of multistage flash (MSF) desalination with hydrate-based desalination (HBD) precursor to improve MSF performance in terms of distillate production, longevity, and operational conditions. This is accomplished by a comprehensive analysis of the rate of scale formation, distillate production, and the MSF performance ratio by means of mathematical modelling conducted in Simulink software. To calibrate the effectiveness of HBD as precursor to the MSF desalination process, two MSF models were created: the once-through (OT) and brine recycle (BR) configurations. The MSF models were validated in terms of stagewise distillate production, brine temperature, and coolant temperatures with data from the literature, while neglecting the non-equilibrium allowance. The operational performance of the proposed integration approach was evaluated in terms of the deposition rates of CaCO₃, scale thickness, fouling resistance, overall heat transfer coefficient, performance ratio, and production ratio. The examination was conducted from the perspective of water salinity and stream temperature for the integrated HBD-MSF systems. The results show that due to the quality of output water in terms of salinity and temperature, the integration of HBD and MSF improved the performance of MSF by substantially reducing scale formation rates as well as increasing the production of distillate where the scale formation rates were 40.6% and 36.3% lower for the hybrid HBD-MSF-OT and HBD-MSF-BR systems, respectively. Full article

(This article belongs to the Section Wastewater Treatment and Reuse)

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13 pages, 13065 KiB

Open AccessReview

A Review of Numerical Modelling of Morphodynamics in Braided Rivers: Mechanisms, Insights and Challenges

by Youfei Hu, Haiyan Yang, Haolan Zhou and Qianwen Lv

Water 2023, 15(3), 595; https://doi.org/10.3390/w15030595 - 2 Feb 2023

Cited by 4 | Viewed by 2959

Abstract

In the past decade, the numerical modelling of braided river morphodynamics has experienced a significant advance due to the increasing computer power and the development of numerical techniques. Numerical models are quite efficient in exploring scenarios with different settings, and they can be [...] Read more.

In the past decade, the numerical modelling of braided river morphodynamics has experienced a significant advance due to the increasing computer power and the development of numerical techniques. Numerical models are quite efficient in exploring scenarios with different settings, and they can be applied to investigate the complicated physics laws of natural braided rivers and manage complex river engineering problems. However, braided river models are far from fully developed, e.g., the representation of flow and sediment transport, model sensitivity, essential effects of sediment transport, bank erosion and vegetation, and require intensive refinement and validation to enhance their prediction accuracy. The recent application of advanced field measurement techniques offers model development a new chance by providing abundant measurement data of a high quality. The present study reviews the essential mechanisms and applications of typical braided river models; compares their accuracy; discusses the recent progress, advantages and shortcomings; and illustrates the challenges and future research trends. Full article

(This article belongs to the Special Issue Research on Applications of Remote Sensing and Geographic Information Systems (GIS) in Water Resources)

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12 pages, 2100 KiB

Open AccessArticle

Threshold Recognition of Water Turbidity for Clogging Prevention during Groundwater Recharge Using Secondary Effluent from Wastewater Treatment Plant

by Shiwei Li, Siyue Wang, Shubin Zou, Yang Wang, Wei Fan and Dan Xiao

Water 2023, 15(3), 594; https://doi.org/10.3390/w15030594 - 2 Feb 2023

Cited by 1 | Viewed by 2557

Abstract

The recharge efficiency during artificial groundwater recharge (AGR) is reduced primarily by clogging that is triggered by suspended particles. However, there are loopholes in the current standards of recharge-water quality for clogging control during AGR, and the threshold values of turbidity to prevent [...] Read more.

The recharge efficiency during artificial groundwater recharge (AGR) is reduced primarily by clogging that is triggered by suspended particles. However, there are loopholes in the current standards of recharge-water quality for clogging control during AGR, and the threshold values of turbidity to prevent clogging have not been reasonably determined. In this study, secondary effluents from wastewater treatment plants (WWTPs) were injected into saturated sand columns to simulate the process of AGR. Batch experiments under different turbidity conditions were conducted, and the numerical modeling of particle transport and deposition was performed to assess the clogging processes. Theories of single-collector contact and interfacial interaction energy were applied to elucidate possible microcosmic mechanisms. The results showed that the diluted secondary effluent (SE) with turbidities of 0.540 ± 0.050, 1.09 ± 0.050, and 1.84 ± 0.060 NTU caused considerable clogging in the porous media, which decreased the relative hydraulic conductivities (K/K₀) by 13.2%, 17.6%, and 83.6%, respectively. The filtered SE with a turbidity of 0.160 NTU did not cause clogging, and K/K₀ was reduced by only 1.70%. The clogging was attributed to the deposition of suspended particles in the sand matrix because they have a high collision efficiency (0.007–1.98) and attachment efficiency (0.029–0.589 k_BT). Finally, this paper recommends that the turbidity of the recharge water should not exceed 0.500 NTU during AGR practices. Full article

(This article belongs to the Special Issue Water Reclamation and Reuse in a Changing World)

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17 pages, 3689 KiB

Open AccessArticle

Effects of Graphene on the Transport of Quinolones in Porous Media

by Zhou Cheng, Cehui Mo, Ming Wu, Huihui Cao, Yanru Hao, Guoping Lu, Qusheng Li, Jianfeng Wu, Jichun Wu and Bill X. Hu

Water 2023, 15(3), 593; https://doi.org/10.3390/w15030593 - 2 Feb 2023

Cited by 1 | Viewed by 2116

Abstract

The effect of graphene (GN) on the transport of CIP and NOR in porous media is investigated by a combination of batch experiments, column experiments and mathematical models. The results obtained by batch experiments show that GN has great adsorption capacity to two [...] Read more.

The effect of graphene (GN) on the transport of CIP and NOR in porous media is investigated by a combination of batch experiments, column experiments and mathematical models. The results obtained by batch experiments show that GN has great adsorption capacity to two antibiotic contaminants, and the maximum adsorption amounts based on the Langmuir model calculation are 270.67 mg/g and 178.36 mg/g, respectively. The column experiments suggest the mobility of CIP and NOR decreases with the mass fraction of GN packed in porous media, and the mass recovery rates of CIP and NOR increase with flow velocity. As the concentration of Na⁺ increases, the mobility of CIP and NOR is enhanced. However, Ca²⁺ has a significant enhancement effect on the mobility of CIP and NOR. Moreover, the transport processes of CIP and NOR in the column are predicted by a BDST mathematical model, and the calculated results are in good agreement with the experimental results. The relationships between kinetic parameters related to QNs’ mobility and GN content, flow velocity and ionic strength are obtained by a regression analysis, which can be used to predict the mobility of CIP and NOR in porous media. Full article

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17 pages, 7536 KiB

Open AccessArticle

Rainfall Forecast and Drought Analysis for Recent and Forthcoming Years in India

by S. Poornima, M. Pushpalatha, Raghavendra B. Jana and Laxmi Anusri Patti

Water 2023, 15(3), 592; https://doi.org/10.3390/w15030592 - 2 Feb 2023

Cited by 13 | Viewed by 10399

Abstract

Agriculture is the primary profession in India which relies on several climatic factors such as rainfall, temperature, humidity, etc., for the successful growth of crops. Weather and drought forecasting may help to take preventive measures in an unusual situation due to crop failure. [...] Read more.

Agriculture is the primary profession in India which relies on several climatic factors such as rainfall, temperature, humidity, etc., for the successful growth of crops. Weather and drought forecasting may help to take preventive measures in an unusual situation due to crop failure. Most of the existing work attempts to forecast the weather or analyse the reason for the occurrence of drought and its effects in the past. This paper adopts the machine learning model called the long short-term memory (LSTM) neural network to forecast the long-term rainfall and standardised precipitation index for drought estimation. The predicted annual rainfall from LSTM is taken as an input to forecast the drought conditions of India for the upcoming years, which is a unique approach and objective, and based on this work appropriate decisions can be made for future actions. The past 117 years of rainfall and drought conditions are compared with the recent 50 years by analysing the data in several ways in order to predict the future scenario. The forecasted results are compared with actual observations to demonstrate the effectiveness of the LSTM model to produce adequate results. The error and network loss of the model is 0.059 and 0.0036, which is minimal, and the forecasted rainfall level is almost equal to actual level specifically accuracy is 99.46% for the previous year, 2021. It was found that there is a rainfall decline of 0.04% every year. Apart from the prediction for the country, a clear picture of the region regarding drought forecasts is presented in this work. The real-time drought level is mild and moderate for most of the regions in the country which matches with the drought level determined using forecasted rainfall. Full article

(This article belongs to the Special Issue Effects of Drought on Agriculture Water Resources and Crop Productivity)

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30 pages, 8396 KiB

Open AccessArticle

Community Agricultural Reservoir Construction and Water Supply Network Design in Ubon Ratchathani, Thailand, Using Adjusted Variable Neighborhood Strategy Adaptive Search

by Rerkchai Srivoramasa, Natthapong Nanthasamroeng, Rapeepan Pitakaso, Thanatkij Srichok, Surajet Khonjun, Worapot Sirirak and Chalermchat Theeraviriya

Water 2023, 15(3), 591; https://doi.org/10.3390/w15030591 - 2 Feb 2023

Viewed by 3464

Abstract

Agricultural sectors all over the world are facing water deficiencies as a result of various factors. Countries in the Greater Mekong Subregion (GMS) in particular depend on the production of agricultural products; thus, drought has become a critical problem in such countries. The [...] Read more.

Agricultural sectors all over the world are facing water deficiencies as a result of various factors. Countries in the Greater Mekong Subregion (GMS) in particular depend on the production of agricultural products; thus, drought has become a critical problem in such countries. The average water level in the lower part of the Mekong River has been decreasing dramatically, resulting in the wider agricultural area of the Mekong watershed facing a lack of water for production. The construction of community reservoirs and associated water supply networks represents a strategy that can be used to address drought problems in the GMS. This study aims to solve the agricultural community reservoir establishment and water supply network design (CR–WSND) problem in Khong Chiam, Ubon Ratchathani, Thailand—a city located in the Mekong Basin. The CR–WSND model is formulated using mixed-integer programming (MIP) in order to minimize the cost of reservoir construction and water irrigation. An adjusted variable neighborhood strategy adaptive search (A-VaNSAS) is applied to a real-world scenario involving 218 nodes, and its performance is compared with that of the original variable neighborhood strategy adaptive search (VaNSAS), differential evolution (DE), and genetic algorithm (GA) approaches. An improved box selection formula and newly designed improvement black boxes are added to enhance the quality beyond the original VaNSAS. The results reveal that the quality of the solution from A-VaNSAS is significantly better than those of GA, DE, and VaNSAS (by 6.27%, 9.70%, and 9.65%, respectively); thus, A-VaNSAS can be used to design a community reservoir and water supply network effectively. Full article

(This article belongs to the Special Issue Using Artificial Intelligence for Smart Water Management)

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16 pages, 1952 KiB

Open AccessArticle

PGPR Promotes the Recovery of Submerged Macrophytes via Indigenous Microbiome Modulations under Combined Abiotic Stress

by Yahua Li, Xiangfen Liu, Qianzheng Li, Yao Guo, Yi Zhang, Chuan Wang, Qiaohong Zhou and Zhenbin Wu

Water 2023, 15(3), 590; https://doi.org/10.3390/w15030590 - 2 Feb 2023

Cited by 4 | Viewed by 2683

Abstract

The restoration of submerged macrophytes is commonly limited by abiotic stress. Here, we isolated PGPR strains from the rhizosphere of submerged macrophytes using ACC deaminase selective medium, and evaluated their growth promoting effects on Vallisneria natans (V. natans) under low light [...] Read more.

The restoration of submerged macrophytes is commonly limited by abiotic stress. Here, we isolated PGPR strains from the rhizosphere of submerged macrophytes using ACC deaminase selective medium, and evaluated their growth promoting effects on Vallisneria natans (V. natans) under low light intensity and (or) high sediment organic matter load, and also explored the indigenous microbiome response of V. natans seedlings to PGPR inoculants. Ten isolates were chosen from the 252 isolated strains based on the ACC deaminase activity and the production of IAA and siderophore. M1 (Pseudomonas vancouverensis) and E15 (Enterobacter ludwigii) had the best growth promoting effects under low light stress and under double stress of low light and high sediment organic matter load, and the shoot height increased by 36% and 46%, respectively. The results of indigenous microbiome analysis showed that PGPR inoculants could regulate the relative abundance of unclassified_f_Enterobacteriaceae and improve the α-diversity of the rhizosphere bacterial community. Under high sediment organic matter load, inoculation of PGPR obviously shifted the β-diversity of rhizosphere bacterial communities to promote the early growth of V. natans. This study expands the application of plant–microbe interaction in the field of freshwater ecological restoration. Full article

(This article belongs to the Special Issue Ecological Restoration of Lakes and Reservoirs)

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16 pages, 7892 KiB

Open AccessArticle

A Unique Approach to Hydrological Behavior along the Bednja River (Croatia) Watercourse

by Bojan Đurin, Lucija Plantak, Ognjen Bonacci and Fabio Di Nunno

Water 2023, 15(3), 589; https://doi.org/10.3390/w15030589 - 2 Feb 2023

Cited by 6 | Viewed by 2560

Abstract

Forecasting upstream flow amount based on downstream flow values is a new way of managing flood risk. This kind of prediction of the flow, size, and intensity of rivers in the alluvial aquifers is, in most cases, a challenging task due to climate [...] Read more.

Forecasting upstream flow amount based on downstream flow values is a new way of managing flood risk. This kind of prediction of the flow, size, and intensity of rivers in the alluvial aquifers is, in most cases, a challenging task due to climate change, as well as anthropogenic impacts on river flows. The presented methodology allows for organizing and preparing measures for flood protection, the operational work of hydropower plants, and many other usages. The methodology consists of correlation, cross-correlation, and a rescaled adjusted partial sums (RAPS) method. Although all methods are known, they have not been used in a methodology like the one presented. Research is conducted on a real case study of the river Bednja, on five consecutive hydrological measurement stations in the northwestern part of Croatia, for an available time series of the average daily flows from 2007–2018. High correlations were observed between the five stations along the Bednja River, with values of the correlation coefficient between 0.85 and 0.97 for the average daily flows, and between 0.88 and 0.99 for the RAPS values. The presented analysis gives information about similarities and connections between all five hydrological stations, which is significant and can be used to predict flow intensity. Full article

(This article belongs to the Special Issue Interference Hydrology-Interference of Human Activities on Hydrological System)

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19 pages, 580 KiB

Open AccessArticle

Comparative Analysis of Natural and Synthetic Zeolite Filter Performance in the Purification of Groundwater

by Kulyash Meiramkulova, Aliya Kydyrbekova, Davud Devrishov, Ubaidulayeva Nurbala, Akmaral Tuyakbayeva, Sayan Zhangazin, Rimma Ualiyeva, Valentina Kolpakova, Yuliya Yeremeyeva and Timoth Mkilima

Water 2023, 15(3), 588; https://doi.org/10.3390/w15030588 - 2 Feb 2023

Cited by 10 | Viewed by 4726

Abstract

Zeolite materials are among the relatively cheap and readily available materials for wastewater treatment. However, the performance of zeolite-based systems can be highly affected by the material properties. In this study, the treatment system based on natural zeolite materials from Chankanai mines in [...] Read more.

Zeolite materials are among the relatively cheap and readily available materials for wastewater treatment. However, the performance of zeolite-based systems can be highly affected by the material properties. In this study, the treatment system based on natural zeolite materials from Chankanai mines in Kazakhstan was compared with a synthetic zeolite treatment system for the purification of groundwater. Water quality indices were also developed from a set of selected water quality parameters to further assess the state of water quality of raw groundwater and the effluents treated with natural and synthetic zeolite. The lowest removal efficiency of natural zeolite (30%) was observed with zinc, while the lowest removal efficiency (36%) of synthetic zeolite was observed with arsenic. With turbidity and beryllium, we observed the maximum removal efficiency (100%) of natural zeolite, whereas with turbidity, we observed the highest removal efficiency (100%) of synthetic zeolite. When the groundwater samples were put through the natural zeolite treatment system, removal efficiency of 50% and above was obtained with 27 (79.4%) out of the 34 water quality parameters examined. On the other hand, when the groundwater samples were put through the synthetic zeolite treatment system, more than 50% removal efficiency was attained with 30 (88.2%) out of the 34 water quality parameters studied. The aggregated water quality index of raw groundwater was 3278.24, falling in the “water unsuitable for drinking” category. The effluent treated with natural zeolite generated 144.82 as a water quality index, falling in the “poor water” quality category. Synthetic zeolite generated 94.79 as a water quality index, falling in the “good water” quality category. Across the board, it was shown that the synthetic zeolite treatment system outperformed the natural zeolite treatment system according to a number of water quality parameters. The findings of this study offer substantial knowledge that can be used to develop more efficient groundwater treatment technologies. Full article

(This article belongs to the Section Wastewater Treatment and Reuse)

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14 pages, 3160 KiB

Open AccessArticle

Development of Water Level Prediction Improvement Method Using Multivariate Time Series Data by GRU Model

by Kidoo Park, Yeongjeong Seong, Younghun Jung, Ilro Youn and Cheon Kyu Choi

Water 2023, 15(3), 587; https://doi.org/10.3390/w15030587 - 2 Feb 2023

Cited by 4 | Viewed by 2817

Abstract

The methods for improving the accuracy of water level prediction were proposed in this study by selecting the Gated Recurrent Unit (GRU) model, which is effective for multivariate learning at the Paldang Bridge station in Han River, South Korea, where the water level [...] Read more.

The methods for improving the accuracy of water level prediction were proposed in this study by selecting the Gated Recurrent Unit (GRU) model, which is effective for multivariate learning at the Paldang Bridge station in Han River, South Korea, where the water level fluctuates seasonally. The hydrological data (i.e., water level and flow rate) for Paldang Bridge station were entered into the GRU model; the data were provided by the Water Resources Management Information System (WAMIS), and the meteorological data for Seoul Meteorological Observatory and Yangpyeong Meteorological Observatory were provided through the Korea Meteorological Administration. Correlation analysis was used to select the training data for hydrological and meteorological data. Important input data affecting the daily water level (DWL) were daily flow rate (DFR), daily vapor pressure (DVP), daily dew point temperature (DDPT), and 1 h max precipitation (1HP), and were used as the multivariate learning data for water level prediction. However, the DWL prediction accuracy did not improve even if the meteorological data from a single meteorological observatory far from the DWL prediction point were used as the multivariate learning data. Therefore, in this study, methods for improving the predictive accuracy of DWL through multivariate learning that effectively utilize meteorological data from each meteorological observatory were presented. First, it was a method of arithmetically averaging meteorological data for two meteorological observatories and using it as the multivariate learning data for the GRU model. Second, a method was proposed to use the meteorological data of the two meteorological observatories as multivariate learning data by weighted averaging the distances from each meteorological observatory to the water level prediction point. Therefore, in this study, improved water level prediction results were obtained even if data with some correlation between meteorological data provided by two meteorological observatories located far from the water level prediction point were used. Full article

(This article belongs to the Special Issue Advanced Machine Learning Techniques for Water)

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23 pages, 7886 KiB

Open AccessArticle

A Machine Learning Approach to Predict Watershed Health Indices for Sediments and Nutrients at Ungauged Basins

by Ganeshchandra Mallya, Mohamed M. Hantush and Rao S. Govindaraju

Water 2023, 15(3), 586; https://doi.org/10.3390/w15030586 - 2 Feb 2023

Cited by 2 | Viewed by 4422

Abstract

Effective water quality management and reliable environmental modeling depend on the availability, size, and quality of water quality (WQ) data. Observed stream water quality data are usually sparse in both time and space. Reconstruction of water quality time series using surrogate variables such [...] Read more.

Effective water quality management and reliable environmental modeling depend on the availability, size, and quality of water quality (WQ) data. Observed stream water quality data are usually sparse in both time and space. Reconstruction of water quality time series using surrogate variables such as streamflow have been used to evaluate risk metrics such as reliability, resilience, vulnerability, and watershed health (WH) but only at gauged locations. Estimating these indices for ungauged watersheds has not been attempted because of the high-dimensional nature of the potential predictor space. In this study, machine learning (ML) models, namely random forest regression, AdaBoost, gradient boosting machines, and Bayesian ridge regression (along with an ensemble model), were evaluated to predict watershed health and other risk metrics at ungauged hydrologic unit code 10 (HUC-10) basins using watershed attributes, long-term climate data, soil data, land use and land cover data, fertilizer sales data, and geographic information as predictor variables. These ML models were tested over the Upper Mississippi River Basin, the Ohio River Basin, and the Maumee River Basin for water quality constituents such as suspended sediment concentration, nitrogen, and phosphorus. Random forest, AdaBoost, and gradient boosting regressors typically showed a coefficient of determination

R^{2} > 0.8

for suspended sediment concentration and nitrogen during the testing stage, while the ensemble model exhibited

R^{2} > 0.95

. Watershed health values with respect to suspended sediments and nitrogen predicted by all ML models including the ensemble model were lower for areas with larger agricultural land use, moderate for areas with predominant urban land use, and higher for forested areas; the trained ML models adequately predicted WH in ungauged basins. However, low WH values (with respect to phosphorus) were predicted at some basins in the Upper Mississippi River Basin that had dominant forest land use. Results suggest that the proposed ML models provide robust estimates at ungauged locations when sufficient training data are available for a WQ constituent. ML models may be used as quick screening tools by decision makers and water quality monitoring agencies for identifying critical source areas or hotspots with respect to different water quality constituents, even for ungauged watersheds. Full article

(This article belongs to the Special Issue Water Quality Assessment and Modelling)

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15 pages, 2018 KiB

Open AccessArticle

Biochemical and Pathophysiological Responses in Capoeta capoeta under Lethal and Sub-Lethal Exposures of Silver Nanoparticles

by Dariush Azadikhah, Ahmad Mohamadi Yalsuyi, Shubhajit Saha, Nimai Chandra Saha and Caterina Faggio

Water 2023, 15(3), 585; https://doi.org/10.3390/w15030585 - 2 Feb 2023

Cited by 13 | Viewed by 2816

Abstract

The increasing use of nano-based products raises concerns regarding potential risks related to their manufacturing, transportation, waste disposal, and management operations. We used the riverine carp, Capoeta capoeta, as an aquatic animal model to demonstrate the acute toxicity of silver nanoparticles (Ag-NPs). [...] Read more.

The increasing use of nano-based products raises concerns regarding potential risks related to their manufacturing, transportation, waste disposal, and management operations. We used the riverine carp, Capoeta capoeta, as an aquatic animal model to demonstrate the acute toxicity of silver nanoparticles (Ag-NPs). This study focuses on acute toxicity first, and then integrates the findings through histopathology, hematological, and biochemical testing of lethal and sub-lethal Ag-NPs exposures. Red blood corpuscles (RBC), white blood corpuscles (WBC), hematocrit, and total serum glucose levels were significantly lower in Ag-NPs-exposed fish than in control fish. Total serum protein, triglycerides, cholesterol, and albumin were all significantly greater in exposed fish. This research focused on the impacts of Ag-NPs on gills and liver tissue, and it was found that the level of injury escalated as the concentration of Ag NPs increased. Epithelial lifting of secondary lamellas (ELSL), epithelial hypertrophy (EH) of secondary lamellae (SL), leukocyte infiltration (LI), and bottom hyperplasia (BH) were all detected in Ag-NPs-exposed fish. In Ag-NPs-treated liver cross-sections of Capoeta capoeta, macrophage aggregates (MA), fatty liver (FL), sinusoid dilatation (SD), and necrosis (N) were identified. Ag-NPs dosages, according to biomarker representations, elicit stress-specific biochemical and physiological effects, compromising the general overall health status of aquatic animals. The gradients of toxic responses across exposure concentrations and portrayals of disrupted fish health with increasing silver nanoparticle exposure time indicate a reduced physiological ability for surviving in the wild. Full article

(This article belongs to the Section Biodiversity and Functionality of Aquatic Ecosystems)

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20 pages, 6702 KiB

Open AccessArticle

Assessment of the Potential Hydrological Impacts of Climate Change in Quebec—Canada, a Refined Neutral Approach

by Marinela del Carmen Valencia Giraldo, Simon Ricard and François Anctil

Water 2023, 15(3), 584; https://doi.org/10.3390/w15030584 - 2 Feb 2023

Viewed by 2483

Abstract

There is currently much discussion as to whether probabilistic (top–down) or possibilistic (bottom–up) approaches are the most appropriate to estimate potential future climate impacts. In a context of deep uncertainty, such as future climate, bottom-up approaches aimed at assessing the sensitivity and vulnerability [...] Read more.

There is currently much discussion as to whether probabilistic (top–down) or possibilistic (bottom–up) approaches are the most appropriate to estimate potential future climate impacts. In a context of deep uncertainty, such as future climate, bottom-up approaches aimed at assessing the sensitivity and vulnerability of systems to changes in climate variables have been gaining ground. A refined framework is proposed here (in terms of coherence, structure, uncertainty, and results analysis) that adopts the scenario–neutral method of the bottom–up approach, but also draws on some elements of the top–down approach. What better guides the task of assessing the potential hydroclimatological impacts of changing climatic conditions in terms of the sensitivity of the systems, differential analysis of climatic stressors, paths of change, and categorized response of the scenarios: past, changing, compensatory, and critical condition. The results revealed a regional behavior (of hydroclimatology, annual water balances, and snow) and a differential behavior (of low flows). We find, among others, the plausible scenario in which increases in temperature and precipitation would generate the same current mean annual flows, with a reduction of half of the snow, a decrease in low flows (significant, but differentiated between basins), and a generalized increase in dry events. Full article

(This article belongs to the Section Water Resources Management, Policy and Governance)

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16 pages, 7123 KiB

Open AccessArticle

Analysis and Prediction of Poyang Lake’s Navigable Conditions under a New Hydrological Regime

by Dong Wang and Tao Zhou

Water 2023, 15(3), 583; https://doi.org/10.3390/w15030583 - 2 Feb 2023

Viewed by 2041

Abstract

Human activities have profoundly changed the hydrological regime and trends of rivers and lakes, which, in turn, has affected the utilization of their navigable conditions. However, few studies have focused on the effects of changes in hydrological regimes and trends of rivers and [...] Read more.

Human activities have profoundly changed the hydrological regime and trends of rivers and lakes, which, in turn, has affected the utilization of their navigable conditions. However, few studies have focused on the effects of changes in hydrological regimes and trends of rivers and lakes on navigable conditions. Thus, this study intensively analyzes and investigates the navigable depth at the major control sections in the lake area during the dry season in the period before 2002, when the Three Gorges Reservoir was not yet constructed, and the period from 2003 to 2019, when the Three Gorges Project was put into operation with impoundment based on the dry-season water level curve in the Poyang Lake area since the operation of the Three Gorges Reservoir. This study also further analyzes the influence of the change in the hydrological regime on the navigable depth in the lake area. The results show that the waterway depth and width could meet the navigation requirements before 2002. From 2003 to 2019, whereas the water level with a 98% guarantee rate of duration at the Xingzi Hydrometric Station decreased, that at the Hukou Hydrometric Station increased. The waterway depth and width at both the Hukou and Xingzi hydrometric stations could meet the requirements of the size of Grade II waterways. This study also performs a simulation prediction of the water regime of Poyang Lake under a new hydrological regime using the mathematical model of water and sediment of the Changjiang River Scientific Research Institute. The results reveal that in 2030 and 2050, after the Three Gorges Reservoir has been in operation for 30–50 years, the water levels at the Hukou, Xingzi, and Wucheng hydrometric stations (Hukou) of Poyang Lake will decline by approximately 0.18–0.66 and 0.10–0.24 m, respectively. Although the overall navigable depth can basically meet the navigation requirements for a period of time, the trend of the long-term declining water level may cause unsafe navigation risks. Full article

(This article belongs to the Special Issue Sustainable Development of Inland Waterways)

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19 pages, 1023 KiB

Open AccessReview

The Quantification of Non-Action Costs as an Incentive to Address Water Pollution Problems

by Águeda Bellver-Domingo, Lledó Castellet-Viciano, Vicent Hernández-Chover and Francesc Hernández-Sancho

Water 2023, 15(3), 582; https://doi.org/10.3390/w15030582 - 2 Feb 2023

Viewed by 3597

Abstract

Diffuse pollution is one type of pollution generated by agricultural, livestock, and urban runoff that is responsible for surface and groundwater pollution. As a result, the exposed population develops different diseases that affect their short, medium, and long-term quality of life. Researchers need [...] Read more.

Diffuse pollution is one type of pollution generated by agricultural, livestock, and urban runoff that is responsible for surface and groundwater pollution. As a result, the exposed population develops different diseases that affect their short, medium, and long-term quality of life. Researchers need to be able to assess the loss of quality of life in monetary terms to include this social impact in decision-making processes. Specifically, if no measure is implemented to correct the situation, these costs can be considered as the non-action costs of the social impact of water pollution. This study assesses the importance of measuring healthcare costs as a proxy for non-action costs for the economic assessment of water pollution consequences. Thanks to this analysis, it is possible to identify the health costs produced by the current environmental situation, making it possible to obtain an economic baseline scenario prior to the implementation of any project or measure. This approach is a novelty in the literature since, to date, healthcare costs have not been related to non-action costs. Including these costs in economic feasibility studies allow us to assess in detail both the social impact of pollution and the social benefits of develop water-quality improvement projects. Full article

(This article belongs to the Section Water Resources Management, Policy and Governance)

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23 pages, 6807 KiB

Open AccessArticle

Simultaneous Removal of Cyanide and Heavy Metals Using Photoelectrocoagulation

by Ahmad Shahedi, Ahmad Khodadadi Darban, Ahmad Jamshidi-Zanjani, Fariborz Taghipour and Mehdi Homaee

Water 2023, 15(3), 581; https://doi.org/10.3390/w15030581 - 1 Feb 2023

Cited by 5 | Viewed by 2966

Abstract

One of the new methods used to remove the contaminants from effluent is the electrocoagulation method, which is sometimes combined with other methods to increase the removal efficiency of contaminants. To simultaneously remove nickel, cyanide, zinc, and copper, the combined method of photo-electrocoagulation [...] Read more.

One of the new methods used to remove the contaminants from effluent is the electrocoagulation method, which is sometimes combined with other methods to increase the removal efficiency of contaminants. To simultaneously remove nickel, cyanide, zinc, and copper, the combined method of photo-electrocoagulation was used along with an oxidizing agent, namely hydrogen peroxide (Hp). In addition, the effects of factors affecting the removal efficiency were studied, including pH, electrode arrangement, and current intensity. An electric current of 300 mA at a pH of 10 for 60 min, Fe-SS electrodes with a distance between them of 5 cm, and hydrogen peroxide at a rate of 4 mg/L were the ideal conditions needed to accomplish the photo-electrocoagulation-oxidation process. According to these study findings, when the combined method of photocatalyst-electrocoagulation-oxidation (Hp) was used, the highest removal efficiencies of nickel, cyanide, zinc, and copper were 85, 96, 94, and 98%, respectively. The results showed that using the combined photo-electrocoagulation-oxidation method increased the efficiency of simultaneous removal of pollutants by 10% compared to conventional electrocoagulation method. The reason for the increase in removal efficiency is the production of hydroxyl radicals simultaneously with the formation of coagulants produced by electrocoagulation process. Full article

(This article belongs to the Special Issue Geochemistry of Water and Sediment III)

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