Water

23 pages, 10410 KiB

Open AccessArticle

Subgrid Model of Fluid Force Acting on Buildings for Three-Dimensional Flood Inundation Simulations

by Riku Kubota, Jin Kashiwada and Yasuo Nihei

Water 2023, 15(17), 3166; https://doi.org/10.3390/w15173166 - 4 Sep 2023

Cited by 1 | Viewed by 1869

In recent years, large-scale heavy rainfall disasters have occurred frequently in several parts of the world. Therefore, a quantitative approach to understanding how buildings are damaged during floods is necessary to develop appropriate flood-resistant technologies. In flood inundation simulations for the quantitative evaluation [...] Read more.

In recent years, large-scale heavy rainfall disasters have occurred frequently in several parts of the world. Therefore, a quantitative approach to understanding how buildings are damaged during floods is necessary to develop appropriate flood-resistant technologies. In flood inundation simulations for the quantitative evaluation of a building’s resistance to flooding, a subgrid model is necessary to appropriately evaluate the resistance of buildings smaller than the grid size at a medium grid resolution. In this study, a new subgrid (SG) 3D inundation model is constructed to evaluate the fluid force acting on buildings and assess the damage to individual buildings during flood inundation. The proposed method does not increase the computational load. The model is incorporated into a 2D and 3D hybrid model with high computational efficiency to construct a 3D river and inundation flow model. Its validity and effectiveness are evaluated through comparisons with field observations and the conventional equivalent roughness model. Considering horizontal and vertical velocity distributions, the proposed model showed statistically significant improvements in performance in terms of building loss indices such as velocity and fluid force. These results suggest that the SG model can effectively evaluate the fluid force acting on buildings, including the vertical distribution of flow velocities. Full article

(This article belongs to the Topic Natural Hazards and Disaster Risks Reduction)

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16 pages, 2550 KiB

Open AccessReview

A Mini-Review of Antibiotic Resistance Drivers in Urban Wastewater Treatment Plants: Environmental Concentrations, Mechanism and Perspectives

by Fuzheng Zhao, Qingmiao Yu and Xu-Xiang Zhang

Water 2023, 15(17), 3165; https://doi.org/10.3390/w15173165 - 4 Sep 2023

Cited by 3 | Viewed by 2862

Abstract

Antibiotic resistance is one of the biggest challenges to public health and ecological safety in the 21st century. Urban wastewater treatment plants (UWTPs), as reservoirs of antibiotic resistance genes (ARGs) and antibiotic-resistant bacteria (ARB), simultaneously contain a wide variety of chemical pollutants. The [...] Read more.

Antibiotic resistance is one of the biggest challenges to public health and ecological safety in the 21st century. Urban wastewater treatment plants (UWTPs), as reservoirs of antibiotic resistance genes (ARGs) and antibiotic-resistant bacteria (ARB), simultaneously contain a wide variety of chemical pollutants. The review introduces the actual concentration levels and the mechanisms of antibiotic resistance drivers (ARDs) in UWTPs, including antibiotics, heavy metals, disinfectants, cosmetics and personal care products, non-antibiotic drugs, and microplastics. Moreover, this review emphasizes the importance of approaching the actual activated sludge environment in future research and proposes future directions. Full article

(This article belongs to the Special Issue Health Issues in Wastewater Treatment and Microbial Risk of Emerging Contaminants Concern Implicated in Antibiotic Resistance)

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23 pages, 4444 KiB

Open AccessArticle

Critical Analysis of Stakeholders in the Municipality of Tarija, Bolivia, in Search of Strategies for Adequate Water Governance to Implement Reverse Osmosis as an Alternative for Generating Safe Water for Its Inhabitants

by Esteban Manuel Villena-Martínez, Paola Andrea Alvizuri-Tintaya, Vanesa Gladys Lo-Iacono-Ferreira, Jaime Lora-García, Juan Ignacio Torregrosa-López, Lorena Sánchez Barrero, Alejandra Leigue Fernández and Paul D’Abzac

Water 2023, 15(17), 3164; https://doi.org/10.3390/w15173164 - 4 Sep 2023

Cited by 1 | Viewed by 1764

Abstract

The accelerated deterioration of water quality in the city of Tarija, Bolivia, has caused several water sources in the Municipality of Tarija to be discontinued due to the presence of toxic contaminants. The current water purification systems that are used in Tarija do [...] Read more.

The accelerated deterioration of water quality in the city of Tarija, Bolivia, has caused several water sources in the Municipality of Tarija to be discontinued due to the presence of toxic contaminants. The current water purification systems that are used in Tarija do not guarantee the elimination of heavy metals; in addition, political and social interest conflicts are a serious problem in the execution of projects and new public investment alternatives, with these being the main problems found in the sector. Reverse osmosis (RO) water purification technologies are one of the most effective contemporary alternatives for the elimination of contaminants in water, such as heavy metals; however, their application and implementation in countries with little or no experience in this type of technology require acceptance and knowledge on behalf of the interested parties. Political and social conflicts between interested parties generate scenarios that affect hydrological planning. Analysis of the actors in the urban and municipal sphere of the city of Tarija, Bolivia, provides a case study for adequate water governance and enabled us to come to a consensus for the implementation of RO. The results show 23 fundamental actors in water management in the Municipality of Tarija, with local actors being those with the greatest influence and power in decision-making. Our analysis of social networks showed an important polarization in the power of decision makers, with municipalities and legislative entities being those that decide on public investments. The interested parties showed considerable interest in the application of RO as a technology that can provide definitive, short-term solutions to the problems of water stress and the water crisis in the Municipality of Tarija and its application in small towns with a high level of social and environmental vulnerability. Full article

(This article belongs to the Section Water-Energy Nexus)

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19 pages, 1361 KiB

Open AccessArticle

Elucidating the Potential of Dye-Degrading Enterobacter cloacae ZA14 for Cultivation of Solanum lycopersicum Plants with Textile Effluents

by Zainab Naseem, Muhammad Naveed, Muhammad Imran, Muhammad Saqlain, Muhammad Asif, Mohsin Bashir, Saud Alamri, Manzer H. Siddiqui, Martin Brtnicky and Adnan Mustafa

Water 2023, 15(17), 3163; https://doi.org/10.3390/w15173163 - 4 Sep 2023

Cited by 6 | Viewed by 2272

Abstract

The presence of textile effluents in water bodies is a matter of concern due to toxicity caused by textile dyes, associated heavy metals and salts. Endophytic bacteria have been reported to reduce the phytotoxicity of textile wastewater (TWW) and improve crop potential. The [...] Read more.

The presence of textile effluents in water bodies is a matter of concern due to toxicity caused by textile dyes, associated heavy metals and salts. Endophytic bacteria have been reported to reduce the phytotoxicity of textile wastewater (TWW) and improve crop potential. The purpose of this study was to sequester dye-degrading endophytic bacteria with the ability to remediate textile effluents and promote tomato plant growth. Six strains showing the highest dye decolorization were screened from the dye decolorization assay. Selected strains also showed plant growth-promoting traits and improved tolerance to heavy metals and salt. The results revealed that Enterobacter cloacae ZA14 showed the highest decolorization (90%) using 200 mg L⁻¹ of dye concentration, high minimum inhibitory concentration (MIC) of heavy metals and improved salt tolerance. In a sand culture experiment, the T4 (25% TWW (consisting of 25 mL TWW with 75 mL distilled water) + ZA14) treatment showed an increase in root length (9.3%), shoot length (5.5%), improved chlorophyll contents (7%), and membrane stability index (5%), whereas maximum oxidative stress was indicated by T10 (100% TWW) with an increase of 122% in MDA and 80% in H₂O₂ as compared to T1. An increase of 41% in ascorbate peroxidase (APX), 37% increase in sodium oxide dismutase (SOD), 27% in peroxidase (POD), and 24% in catalase (CAT) by T4 treatment showed the least production of antioxidants as compared to plants receiving 50%, 75% and 100% TWW along with ZA14 application. These results suggested that 25% TWW is beneficial for crop production with the use of an appropriate approach like Enterobacter cloacae ZA14 to mitigate textile effluents efficiently and to improve crop production. Full article

(This article belongs to the Special Issue Water and Soil Pollution Restoration)

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Potential of various endophytic strains to decolorize direct blue (200 mg L−1) azo dye isolated from (A) textile wastewater sample and (B) plant sample. Data showed means of three replicates at p < 0.05. Full article ">Figure 2
The combined effect of endophytic strains and textile wastewater on (a) chlorophyll content (SPAD value), (b) relative water content and (c) membrane stability index of tomato plants. In each figure, the data is mean of three replicates ± SE and the bars sharing similar letters do not differ significantly at p < 0.05; T1 = control (DW); T2 = ZA14; T3 = 25% TWW; T4 = ZA14 + 25% TWW; T5 = 50% TWW; T6 = ZA14 + 50% TWW; T7 = 75% TWW; T8 = ZA14 + 75% TWW; T9 = 100 TWW; T10 = ZA14 + 100% TWW. Full article ">Figure 3
The combined effect of endophytic strains and textile wastewater on the production of oxidative stress markers; (a) MDA, (b) H2O2, (c) proline and (d) and glycine betaine in tomato plants. In each figure, the data is mean of three replicates ± SE and the bars sharing similar letters do not differ significantly at p < 0.05; T1 = control (DW); T2 = ZA14; T3 = 25% TWW; T4 = ZA14 + 25% TWW; T5 = 50% TWW; T6 = ZA14 + 50% TWW; T7 = 75% TWW; T8 = ZA14 + 75% TWW; T9 = 100 TWW; T10 = ZA14 + 100% TWW. Full article ">Figure 4
Combined effect of endophytic strains and textile wastewater on production of secondary metabolites; (a) total flavonoids, (b) total phenols and (c) total anthocyanins in tomato plants. In each figure, the data is mean of three replicates ± SE and the bars sharing similar letters do not differ significantly at p < 0.05; T1 = control (DW); T2 = ZA14; T3 = 25% TWW; T4 = ZA14 + 25% TWW; T5 = 50% TWW; T6 = ZA14 + 50% TWW; T7 = 75% TWW; T8 = ZA14 + 75% TWW; T9 = 100 TWW; T10 = ZA14 + 100% TWW. Full article ">Figure 5
The combined effect of endophytic strains and textile wastewater on production of antioxidants; (a) APX, (b) SOD, (c) POD and (d) and CAT in tomato plants. In each figure, the data is mean of three replicates ± SE and the bars sharing similar letters do not differ significantly at p < 0.05; T1 = control (DW); T2 = ZA14; T3 = 25% TWW; T4 = ZA14 + 25% TWW; T5 = 50% TWW; T6 = ZA14 + 50% TWW; T7 = 75% TWW; T8 = ZA14 + 75% TWW; T9 = 100 TWW; T10 = ZA14 + 100% TWW. Full article ">

14 pages, 4286 KiB

Open AccessArticle

Climate Change Impact on Inflow and Nutrient Loads to a Warm Monomictic Lake

by Behnam Parmas, Roohollah Noori, Seyed Abbas Hosseini and Mojtaba Shourian

Water 2023, 15(17), 3162; https://doi.org/10.3390/w15173162 - 4 Sep 2023

Cited by 1 | Viewed by 1272

Abstract

This study analyses the impact of climate change on the inflows, sediment loads, and nutrient inputs to the Sabalan dam reservoir, a warm monomictic lake located northwest of Iran. For this purpose, the Soil and Water Assessment Tool (SWAT) was calibrated (2005–2018) and [...] Read more.

This study analyses the impact of climate change on the inflows, sediment loads, and nutrient inputs to the Sabalan dam reservoir, a warm monomictic lake located northwest of Iran. For this purpose, the Soil and Water Assessment Tool (SWAT) was calibrated (2005–2018) and validated (2001–2004). Future climate-based data under the AR5 emission scenarios were obtained from the HadGEM2–ES general circulation model and then downscaled using the LARSWG 6.0. The tuned SWAT model was used to investigate the climate change impact on the hydrological processes and pollution loads to the Sabalan dam reservoir. Our findings based on the Nash–Sutcliffe efficiency coefficient and the coefficient of determination indicated an acceptable performance of the SWAT model in the simulation of inflows, sediment loads, and nutrient inputs to the reservoir. Inflow and sediment load to the reservoir will increase during the period of 2030–2070 compared to the base period (1998–2018). The annual total nitrogen (phosphorus) load to the reservoir will increase by 8.5% (9.4%), 7.3% (8.2%), and 5% (3.4%) under the emission scenarios of RCP2.6, RCP4.5, and RCP8.5, respectively. An increase in sediment loads and nutrient inputs to the Sabalan dam reservoir will significantly exacerbate the reservoir eutrophic condition, leading to water quality deterioration with acute consequences for the positive functions of the dam. Full article

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(a) The watershed of the Sabalan dam reservoir together with the locations of the hydrometric, synoptic, and water quality stations, the Sabalan dam, and the land use/cover map. (b) The main tributaries in the Sabalan dam watershed together with the main cities and dams. C1 and C2: Arbab Kandi and Barough synoptic stations, respectively; S1 to S5: Kouzeterapi, Polealmas, Samiyan, Shamsabad, and Gilandeh hydrometric stations; W1: Arbab Kandi water quality station. Full article ">Figure 2
Annual and seasonal changes in maximum and minimum air temperature at two synoptic stations under the RCP2.6, RCP4.5, and RCP8.5 scenarios in the watershed of Sabalan dam reservoir during the period of 2030–2070 compared with the base period (1998–2018). Full article ">Figure 3
Annual and seasonal changes in precipitation at two synoptic stations under the RCP2.6, RCP4.5, and RCP8.5 scenarios in the watershed of Sabalan dam reservoir during the period of 2030–2070 compared with the base period (1998–2018). Full article ">Figure 4
Time series of observed and simulated monthly streamflow and sediment load in both calibration and validation of SWAT model during the study base period. Full article ">Figure 5
Time series of observed and simulated monthly total phosphor and total nitrogen in both calibration and validation of SWAT model during the study base period. Full article ">Figure 6
Seasonal and annual changes in inflows, sediment loads, total nitrogen, and total phosphorus inputs to the Sabalan dam reservoir under the RCP2.6, RCP4.5, and RCP8.5 scenarios during 2030–2070 compared to the base period. Full article ">

15 pages, 3091 KiB

Open AccessArticle

Water Protection Zones—Impacts on Weed Vegetation of Arable Soil

by Jan Winkler, Tomáš Řičica, Věra Hubačíková, Eugeniusz Koda, Magdalena Daria Vaverková, Ladislav Havel and Mariusz Żółtowski

Water 2023, 15(17), 3161; https://doi.org/10.3390/w15173161 - 4 Sep 2023

Cited by 2 | Viewed by 1567

Abstract

The aim of this study is to evaluate the occurrence of weeds under conditions of limited herbicide use due to the protection zone of water resources. A total of 23 weed species were found in maize stands, 19 species were found in wheat [...] Read more.

The aim of this study is to evaluate the occurrence of weeds under conditions of limited herbicide use due to the protection zone of water resources. A total of 23 weed species were found in maize stands, 19 species were found in wheat stands, and 16 species were found in rapeseed stands. The redundancy analysis (RDA) results show significant differences in weed occurrence and composition due to herbicide regulation in each crop. Changes in weed composition induced by herbicide application limitations lead to a preference for more specialized weed species (specialists) at the expense of widespread species (generalists). Limiting the use of pesticides in sensitive and vulnerable areas, such as water sources, bodies, and watercourses, is justified from the perspective of protecting the aquatic environment and biodiversity. However, such measures can cause weed growth that is difficult to control, and therefore, it is important to search for new methods for weed control in field crops. Determining a balance between safeguarding water resources and addressing agricultural challenges remains crucial for sustainable land and water management. Full article

(This article belongs to the Special Issue Advances in Ecohydrology in Arid Inland River Basins)

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11 pages, 1048 KiB

Open AccessArticle

A New Method of Water Supply in Crisis Situation

by Dawid Szpak and Agnieszka Szczepanek

Water 2023, 15(17), 3160; https://doi.org/10.3390/w15173160 - 4 Sep 2023

Cited by 2 | Viewed by 1770

Abstract

When it is not possible to supply water through the water supply network, it is necessary to use other resources of the water supply company, e.g., water tanker. This requires maintaining the efficiency of alternative water sources (in terms of quality and quantity). [...] Read more.

When it is not possible to supply water through the water supply network, it is necessary to use other resources of the water supply company, e.g., water tanker. This requires maintaining the efficiency of alternative water sources (in terms of quality and quantity). This work focuses on the possibility of using water accumulated in water pipes in a crisis situation. This work proposes a drain well to supply the population with water in a crisis situation. Thanks to this solution, the function of water supply drainage can be combined with the possibility of obtaining water accumulated in water pipes in crisis conditions. In addition, the standards for water demand in a crisis situation are analyzed. This work extends the view on the problem of water supply to residents in a crisis situation by taking into account a new solution that allows the consumption of water accumulated in water pipes. Full article

(This article belongs to the Special Issue Freshwater Security and Safety Management: New Approaches and Advanced Technologies)

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21 pages, 3656 KiB

Open AccessArticle

Application of Sustainability Index of Tidal River Management (SITRM) in the Lower Ganges–Brahmaputra–Meghna Delta

by Md. Mahedi Al Masud, Hossein Azadi, Abul Kalam Azad, Imaneh Goli, Marcin Pietrzykowski and Thomas Dogot

Water 2023, 15(17), 3159; https://doi.org/10.3390/w15173159 - 4 Sep 2023

Viewed by 1491

Abstract

The sustainability index (SI) is a relatively new concept for measuring the performance of water resource systems over long time periods. The purpose of its definition is to provide an indication of the integral behavior of the system with regard to [...] Read more.

The sustainability index (SI) is a relatively new concept for measuring the performance of water resource systems over long time periods. The purpose of its definition is to provide an indication of the integral behavior of the system with regard to possible undesired consequences if a misbalance in available and required waters occurs. Therefore, the tidal river management (TRM) approach has been implemented for the past three decades (from 1990 to 2020) within the polder system in Southwest Bangladesh to achieve water sustainability. TRM plan and watershed management plan (WMP) have commonalities as both are aimed at ensuring the sustainable use of watershed resources with the management of land, water, and the wider ecosystem of the watershed in an integrated way. The TRM plan focuses mostly on coastal regions, whereas the WMP focuses on both coastal and non-coastal regions. According to this, the aim of this study was to explore the application of the sustainability index of tidal river management (SITRM) in measuring the sustainability of tidal river management in the coastal area of the Lower Ganges–Brahmaputra–Meghna (GBM) delta. In order to quantify the sustainability of tidal river management, this research first provided the components and indicators of SITRM for the coastal region. The study follows a 5-point Likert scale for opinion survey of key informants and comprises households’ survey of farmers. In addition, it includes Landsat satellite images from Earth Explorer of the United States Geological Survey (USGS) and direct field observation to collect information regarding the indicators of SITRM. The study measures the index value of SITRM for identifying the water sustainability of Beel East Khukshia-TRM. The index value was 71.8 out of 100, showing good tidal river management for the Hari–Teka–Bhadra catchment. To achieve water sustainability and aid stakeholders and water managers in decision making, it may be possible to include the SITRM framework in tidal river management projects. In addition, the SITRM is more capable of facing drainage congestion, waterlogging, and climate change issues than watershed sustainability index (WSI), Canadian water sustainability index (CWSI), West Java water sustainability index (WJWSI), and water poverty index (WPI). Therefore, water professionals and policymakers can apply SITRM to assess the resilience of specific TRM schemes for greater sustainability in different coastal regions of the world. Full article

(This article belongs to the Section Hydrology)

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20 pages, 7642 KiB

Open AccessArticle

Groundwater Function Zoning for Groundwater Management Based on RSF, EEF, and GEF in the Plain of the Central Plains Urban Agglomeration, China

by Xiaojing Hu, Chuanming Ma, Xu Guo, Yonggang Li, Hanxiang Xiong, Yang Qiu and Hao Cui

Water 2023, 15(17), 3158; https://doi.org/10.3390/w15173158 - 4 Sep 2023

Viewed by 1317

Abstract

Groundwater function zoning is an important means to ensure that groundwater plays its various functions, which can provide a scientific basis for the protection and development of groundwater resources. Water resources are scarce in the Central Plains Urban Agglomeration (CPUA), so it is [...] Read more.

Groundwater function zoning is an important means to ensure that groundwater plays its various functions, which can provide a scientific basis for the protection and development of groundwater resources. Water resources are scarce in the Central Plains Urban Agglomeration (CPUA), so it is of great significance to evaluate groundwater vulnerability and to zone groundwater function in this area. In this study, the resource supply function (RSF), eco-environment function (EEF), and geo-environment function (GEF) of groundwater were analyzed using the analytic hierarchy process (AHP), maximum method, and dominant mark method, so as to divide the shallow groundwater function in the plain of the CPUA. The results show that the reservation areas (32.0%) are distributed in the areas from Luoning County to Yanjin County, Changyuan County to Xinzheng County, and the areas near mountainous in the south of the CPUA. The geological-disaster-prone areas (29.5%) are distributed in the areas from Ruyang County to Luohe City, Weihui County to Jiyuan City, Xingyang County to Changge County, Changyuan County to Yuanyang County, and Kaifeng City. The development and utilization areas (6.4%) are distributed near mountainous areas in the CPUA. The ecologically vulnerable areas (7.5%) are distributed in the east of Kaifeng City and the northeast of Xinxiang City. The conservation areas (24.6%) are distributed in the areas from Ruyang County to Wuyang County, Xinzheng County to Xingyang County, the north of Xuchang City, the east of Luohe City, Kaifeng City, and Xinxiang City. In order to better manage the groundwater, this study evaluates the vulnerability of the groundwater using the DRASTIC model and makes a single indicator sensitivity analysis. The results show that the accuracies of indicators D, A, and I are particularly important for this vulnerability evaluation. According to the groundwater vulnerability and the land use types, some suggestions were put forward. The research results can provide a reference for groundwater management and development in the CPUA and other areas. Full article

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

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16 pages, 4640 KiB

Open AccessArticle

Changes of Water Consumption in a Forester’s Lodge in Polesie National Park (Poland)—Case Study

by Anna Myka-Raduj, Krzysztof Jóźwiakowski, Tadeusz Siwiec and Waldemar Raduj

Water 2023, 15(17), 3157; https://doi.org/10.3390/w15173157 - 4 Sep 2023

Cited by 4 | Viewed by 1269

Abstract

The object of the present study was to analyse water consumption in a four-person household (park employee housing) located in the village of Kulczyn in Polesie National Park (PNP) in Poland. The wastewater from the buildings was discharged to a hybrid constructed wetland [...] Read more.

The object of the present study was to analyse water consumption in a four-person household (park employee housing) located in the village of Kulczyn in Polesie National Park (PNP) in Poland. The wastewater from the buildings was discharged to a hybrid constructed wetland integrated into a closed-loop water system. As part of the study, seasonal, weekly, and daily changes in water consumption and the amount of water used to flush the toilets were determined over a period of one year. It was shown that the average daily water consumption in the entire house was 437 L/d, or 109 L/p/d (litres/person/day). The average daily water consumption per capita was, therefore, similar to that reported for Poland by the European Commission and much lower than that reported for Western European countries (150–250 L/p/d). The highest water withdrawals were recorded in the spring season (March–May) at 117–122 L/p/d, and the lowest in the holiday month of July—88 L/p/d. The highest water consumption levels during the week were recorded on Saturdays—an average of 136 L/p/d, and the lowest on Wednesdays—an average of 92 L/p/d. During the 24 h of a day, the highest water withdrawals were observed late in the evening (10–11 pm) and periodically in the morning (around 10 am), on weekends, and during the holiday period (July and August). It was shown that the amount of water used to flush toilets represented on average about 20% of the total amount of water consumed. This indicates that approximately 88 L/d of water was used to flush the toilets in the homestead under study. Full article

(This article belongs to the Special Issue Water Treatment, Innovative Method of Management and Regional Prospect of Pollutants)

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Geographical location of the employee housing unit in Kulczyn, in Polesie National Park, and in Poland (compiled by Waldemar Raduj, PNP). Full article ">Figure 2
Employee housing unit in Kulczyn, Polesie National Park—location of facilities on the plot: 1—outbuilding; 2—residential building; 3—primary settling tank; 4—pumping station; 5—hybrid constructed wetland integrated into a closed water circuit (photo by Radomir Obroślak). Full article ">Figure 3
An example of hourly distribution of per capita water consumption in January 2022, sorted from the lowest to the highest value. Full article ">Figure 4
An example of daily distribution of per capita water consumption in 2022, sorted from the lowest to the highest value. Full article ">Figure 5
Mean water consumption during each hour of the day, calculated on the basis of draw-offs on all days of the individual calendar quarters ((A)—Winter, (B)—Spring, (C)—Summer, (D)—Autumm). Full article ">Figure 6
Mean water consumption for each hour of the day, calculated from measurements taken on all days of each month ((A)—January, (B)—February, (C)—March, (D)—April, (E)—May, (F)—June, (G)—July, (H)—August, (I)—September, (J)—October, (K)—November, (L)—December). Full article ">Figure 6 Cont.
Mean water consumption for each hour of the day, calculated from measurements taken on all days of each month ((A)—January, (B)—February, (C)—March, (D)—April, (E)—May, (F)—June, (G)—July, (H)—August, (I)—September, (J)—October, (K)—November, (L)—December). Full article ">Figure 6 Cont.
Mean water consumption for each hour of the day, calculated from measurements taken on all days of each month ((A)—January, (B)—February, (C)—March, (D)—April, (E)—May, (F)—June, (G)—July, (H)—August, (I)—September, (J)—October, (K)—November, (L)—December). Full article ">Figure 7
Mean water consumption during each hour of the day, calculated on the basis of measurements taken on each day of the week ((A)—Mondays, (B)—Tuesdays, (C)—Wednesdays, (D)—Thursdays, (E)—Fridays, (F)—Saturdays, (G)—Sundays). Full article ">Figure 8
The amount of water used for flushing toilets in relation to total per capita water consumption. Full article ">

17 pages, 1363 KiB

Open AccessArticle

Strong and Weak Supervision Combined with CLIP for Water Surface Garbage Detection

by Yunlin Ma, Zhenxiong Chu, Hao Liu, Ye Zhang, Chengzhao Liu, Dexin Li and Wei He

Water 2023, 15(17), 3156; https://doi.org/10.3390/w15173156 - 4 Sep 2023

Cited by 2 | Viewed by 1862

Abstract

Water surface garbage has a significant impact on the protection of water environments and ecological balance, making water surface garbage object detection a critical task. Traditional supervised object detection methods require a large amount of annotated data. To address this issue, we propose [...] Read more.

Water surface garbage has a significant impact on the protection of water environments and ecological balance, making water surface garbage object detection a critical task. Traditional supervised object detection methods require a large amount of annotated data. To address this issue, we propose a method that combines strong and weak supervision with CLIP (Contrastive Language–Image Pretraining) for water surface garbage object detection. First, we train on a dataset annotated with strong supervision, using traditional object detection algorithms to learn the location information of water surface garbage. Then, we input the water surface garbage images into CLIP’s visual encoder to obtain visual feature representations. Simultaneously, we train CLIP’s text encoder using textual description annotations to obtain textual feature representations of the images. By fusing the visual and textual features, we obtain comprehensive feature representations. In the weak supervision training phase, we input the comprehensive feature representations into the object detection model and employ a training strategy that combines strong and weak supervision to detect and localize water surface garbage. To further improve the model’s performance, we introduce attention mechanisms and data augmentation techniques to enhance the model’s focus and robustness towards water surface garbage. By conducting experiments on two water surface garbage datasets, we validate the effectiveness of the proposed method based on the combination of strong and weak supervision with CLIP for water surface garbage object detection tasks. Full article

(This article belongs to the Special Issue Water Engineering Safety and Management)

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14 pages, 6216 KiB

Open AccessArticle

Invasive and Rare Aquatic Invertebrates of Taiwan with a Focus on Their Dormancy

by Victor Alekseev, Hans-Uwe Dahms, Jiang-Shiou Hwang and Natalia Sukhikh

Water 2023, 15(17), 3155; https://doi.org/10.3390/w15173155 - 4 Sep 2023

Cited by 1 | Viewed by 1817

Abstract

Invertebrates in tropical ecosystems are generally considered to have little or no need for a dormant phase due to the stability of the habitat. However, resting stages of aquatic organisms are occasionally found here as well. This fact increases the possibility of transport [...] Read more.

Invertebrates in tropical ecosystems are generally considered to have little or no need for a dormant phase due to the stability of the habitat. However, resting stages of aquatic organisms are occasionally found here as well. This fact increases the possibility of transport of tropical organisms by ships’ ballast water, which is the main vector for the spread of alien aquatic organisms between continents. During a study of resting stages in the bottom sediments of the island of Taiwan in 2006–2007, nine species of invertebrates were found, invasive or new to the fauna of the island, with some of them forming large banks of resting stages in sediments. Full article

(This article belongs to the Special Issue Biological Invasion in Aquatic Ecosystems)

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15 pages, 6549 KiB

Open AccessArticle

Spatio-Temporal Variation of Trophic Status and Water Quality with Water Level Fluctuation in a Reservoir

by Wenwen Liao, Hsinan Chen, Meijeng Peng and Tawei Chang

Water 2023, 15(17), 3154; https://doi.org/10.3390/w15173154 - 3 Sep 2023

Cited by 1 | Viewed by 1538

Abstract

Water level fluctuation (WLF) is one of the important factors that affect reservoir water quality, habitat, species, and ecosystems. In this study, an independent sample t-test was used to evaluate the trophic status and water quality of the spatial and temporal variations [...] Read more.

Water level fluctuation (WLF) is one of the important factors that affect reservoir water quality, habitat, species, and ecosystems. In this study, an independent sample t-test was used to evaluate the trophic status and water quality of the spatial and temporal variations with WLF in Shihmen Reservoir, Taiwan. The results of this study show that the Shihmen Reservoir has the lowest mean water level and higher potential of showing eutrophic status in April and May. This may be attributed to a lower water level, water depth, and transparency in this period. However, although there is no statistically significant difference in mean algal abundance in spring compared with other seasons, seasonal mean algae abundance and the seasonal mean Carlson’s trophic status index (CTSI) show as highly and positively correlated. It means that the increase in the CTSI value may not only be caused by effects on the sediment increase but also by algal proliferation. Mean water depth seems to be one of the important key indexes for reservoir management regarding trophic status since it reflects water quality and can be easy to obtain. This study suggests that reservoir administration can use the water level as a reference threshold for controlling CTSI strategies. In proper hydrological conditions, administration should try to hold a higher water level in a reservoir to downgrade CTSI. Full article

(This article belongs to the Special Issue The Impact of Water Level Changes (Frequency and Amplitude) on Water Quality in Lakes)

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Map of the study area and 5 water quality monitoring station locations in Shihmen Reservoir. (The blue area shows storage area of the Shimen Reservoir, and the yellow dots represent the locations of water quality monitoring stations). Full article ">Figure 2
Monthly variations of mean CTSI and other water quality parameters with the water level in Shihmen Reservoir from 2011 to 2021; (a) CTSI, (b) EC, (c) NH4+-N, (d) SS. (J-11 represents January in 2011). Full article ">Figure 3
Variations of mean CTSI and other water quality parameters with the water level in each month in Shihmen Reservoir from 2011 to 2021; (a) CTSI, (b) TP, (c) Chl-a, (d) transparency, (e) algal abundance (seasonal), (f) EC, (g) TOC, (h) turbidity, (i) NH4+-N, (j) NO3−-N, (k) SS, (l) WQI. Full article ">Figure 4
The TSI deviation graph (a) and correlation of mean algae abundance and mean CTSI (b) of all Shihmen Reservoir data during 2011 to 2021. Full article ">Figure 5
Variations of mean CTSI and other water quality parameters with water depth at the 5 monitoring stations in Shihmen Reservoir from 2011 to 2021; (a) CTSI, (b) TP, (c) Chl-a, (d) transparency, (e) algal abundance, (f) EC, (g) TOC, (h) turbidity, (i) NH4+-N, (j) NO3−-N, (k) SS, (l) WQI. Full article ">Figure 6
Regression analysis of mean CTSI with WLF in 5 monitoring stations of Shihmen Reservoir from 2011 to 2021. (○ represents data without algae abundance data; ● represents data with algae cells no. under 10,000 cells/mL; ● represents data algae cells no. between 10,000 ~ 20,000 cells/mL; ● represents data with algae cells no. above 20,000 cells/mL). Full article ">Figure 7
Regression analysis of mean CTSI with WLF in Shihmen Reservoir from 2011 to 2021. Full article ">Figure 8
Relationship of mean CTSI and (a) algal abundance and (b) transparency with WLF in Shihmen Reservoir from 2011 to 2021. Full article ">

19 pages, 6065 KiB

Open AccessArticle

Study on Dynamic Early Warning of Flash Floods in Hubei Province

by Yong Tu, Yanwei Zhao, Lingsheng Meng, Wei Tang, Wentao Xu, Jiyang Tian, Guomin Lyu and Nan Qiao

Water 2023, 15(17), 3153; https://doi.org/10.3390/w15173153 - 3 Sep 2023

Cited by 1 | Viewed by 1538

Abstract

Flash floods are ferocious and destructive, making their forecasting and early warning difficult and easily causing casualties. In order to improve the accuracy of early warning, a dynamic early warning index system was established based on the distributed spatio-temporally mixed model through a [...] Read more.

Flash floods are ferocious and destructive, making their forecasting and early warning difficult and easily causing casualties. In order to improve the accuracy of early warning, a dynamic early warning index system was established based on the distributed spatio-temporally mixed model through a case study of riverside villages in Hubei Province. Fully taking into account previous rainfall and assuming different rainfall conditions, this work developed a dynamic early warning threshold chart by determining critical rainfall thresholds at different soil moisture levels (dry, normal, wet, and saturated) through pilot calculations, to support a quick query of the critical rainfall at any soil moisture level. The research results show that of the 74 counties and districts in Hubei Province, more than 50% witnessed higher mean critical rainfall than empirical thresholds when the soil was saturated, and about 90% did so when the soil was dry. In 881 towns, a total of 456 early warnings were generated based on dynamic thresholds from 2020 to 2022, 15.2% more than those based on empirical thresholds. From the perspective of total rainfall, dynamic early warnings were generated more frequently in wet years, while empirical early warnings were more frequent in dry years, and the frequency of two warnings were roughly the same in normal years. There were more early warnings based on empirical thresholds in May each year, but more based on dynamic thresholds in June and July, and early warnings generated based on the two methods were almost equal in August and September. Spatially, after dynamic early warning thresholds were adopted, Shiyan and Xiangyang, both northwestern cities in Hubei Province, witnessed significant increases in early warnings. In terms of the early warning mechanism, dynamic early warning took into account the impact of soil moisture and analyzed the flood discharge capacity of river channels according to the flood stage of the riverside villages. On this basis, the rainfall early warning thresholds under different conditions were determined. This is a refined early warning method that could improve the accuracy of flash flood warnings in Hubei Province. Full article

(This article belongs to the Special Issue Advances in Flood and Drought Disaster Forecasting and Early Warnings through Integrating Hydrological and Hydrodynamic Models)

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19 pages, 3710 KiB

Open AccessArticle

Absorption and Utilization of Pollutants in Water: A Novel Model for Predicting the Carrying Capacity and Sustainability of Buildings

by Enyang Mei and Kunyang Yu

Water 2023, 15(17), 3152; https://doi.org/10.3390/w15173152 - 3 Sep 2023

Viewed by 1515

Abstract

The combination of water management and urban planning can promote the sustainable development of cities, which can be achieved through buildings’ absorption and utilization of pollutants in water. Sulfate ions are one of the important pollutants in water, and concrete is an important [...] Read more.

The combination of water management and urban planning can promote the sustainable development of cities, which can be achieved through buildings’ absorption and utilization of pollutants in water. Sulfate ions are one of the important pollutants in water, and concrete is an important building material. The absorption of sulfate ions by concrete can change buildings’ bearing capacity and sustainability. Nevertheless, given the complex and heterogeneous nature of concrete and a series of chemical and physical reactions, there is currently no efficient and accurate method for predicting mechanical performance. This work presents a deep learning model for establishing the relationship between a water environment and concrete performance. The model is constructed using an experimental database consisting of 1328 records gathered from the literature. The utmost essential parameters influencing the compressive strength of concrete under a sulfate attack such as the water-to-binder ratio, the sulfate concentration and type, the admixture type and percentage, and the service age are contemplated as input factors in the modeling process. The results of using several loss functions all approach 0, and the error between the actual value and the predicted value is small. Moreover, the results also demonstrate that the method performed better for predicting the performance of concrete under water pollutant attacks compared to seven basic machine learning algorithms. The method can serve as a reference for the integration of urban building planning and water management. Full article

(This article belongs to the Special Issue Water-Sensitive and Sustainable Urban Development)

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14 pages, 4427 KiB

Open AccessArticle

Quantitative 3D Characterization of Pore Structure in Malan Loess from Different Regions of the Loess Plateau

by Yalin Nan, Ya-Ni Wei, Kui Liu and Yanbo Cao

Water 2023, 15(17), 3151; https://doi.org/10.3390/w15173151 - 3 Sep 2023

Cited by 4 | Viewed by 1426

Abstract

The micro pores in loess show regional variation in structure on the Loess Plateau and greatly influence the physical properties and macro behaviors of loess. In this study, the 3D microstructures of Malan loess from Lanzhou (LZ), Qingyang (QY), Hengshan (HS) and Jingyang [...] Read more.

The micro pores in loess show regional variation in structure on the Loess Plateau and greatly influence the physical properties and macro behaviors of loess. In this study, the 3D microstructures of Malan loess from Lanzhou (LZ), Qingyang (QY), Hengshan (HS) and Jingyang (JY) were established based on μ-CT scanning, and the corresponding microstructural parameters were compared and analyzed quantitatively. The results indicate that the LZ and HS loess both show overall homogeneous structures with dominant inter-particle pores, while the QY and JY loess have more intra-aggregate and constricted pores. Overall, the LZ loess has the largest pore size, followed by the JY loess, QY loess and HS loess, which is consistent with the throat sizes of the four loess samples. The average coordination numbers (CNs) of the LZ and HS loess are lower than those of the QY and JY loess, while the throat lengths of the former two loess are larger than those of the latter two loess. Analysis of the correlation between the micropore parameters and macro behaviors of the loess suggests that the void ratio is the precondition for loess collapse, but it shows weak relevance to collapsibility; meanwhile, the size of pores contributing to the major pore space presents a strong positive correlation. The throat length representing the pore structure is more closely related to loess permeability compared with the void ratio, average CN and throat size. Full article

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20 pages, 7467 KiB

Open AccessArticle

Snow Albedo Reduction in the Colombian Andes Mountains Due to 2000 to 2020 Saharan Dust Intrusions Events

by Tomás R. Bolaño-Ortiz, Viverlys L. Díaz-Gutiérrez, Andrés M. Vélez-Pereira, Eliana L. Vergara-Vásquez and Yiniva Camargo-Caicedo

Water 2023, 15(17), 3150; https://doi.org/10.3390/w15173150 - 3 Sep 2023

Cited by 2 | Viewed by 2277

Abstract

This article investigates the snow albedo changes in Colombian tropical glaciers, namely, Sierra Nevada de Santa Marta (SNSM), Sierra Nevada del Cocuy (NSC), Nevado del Ruíz (NDR), Nevado Santa Isabel (NDS), Nevado del Tolima (NDT), and Nevado del Huila (NDH). They are associated [...] Read more.

This article investigates the snow albedo changes in Colombian tropical glaciers, namely, Sierra Nevada de Santa Marta (SNSM), Sierra Nevada del Cocuy (NSC), Nevado del Ruíz (NDR), Nevado Santa Isabel (NDS), Nevado del Tolima (NDT), and Nevado del Huila (NDH). They are associated with the possible mineral dust deposition from the Sahara Desert during the June and July months using snow albedo (SA), snow cover (SC), and land surface temperature (LST) from the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Terra and Aqua satellites. And mineral dust (MD) from The Modern-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2), both of them during 2000–2020. Results show the largest snow albedo reductions were observed at 39.39%, 32.1%, and 30.58% in SNC, SNSM, and NDR, respectively. Meanwhile, a multiple correlation showed that the glaciers where MD contributed the most to SA behavior were 35.4%, 24%, and 21.4% in NDS, NDC, and NDR. Results also display an increasing trend of dust deposition on Colombian tropical glaciers between 2.81 × 10⁻³ µg·m⁻²·year⁻¹ and 6.58 × 10⁻³ µg·m⁻²·year⁻¹. The results may help recognize the influence of Saharan dust on reducing snow albedo in tropical glaciers in Colombia. The findings from this study also have the potential to be utilized as input for both regional and global climate models. This could enhance our comprehension of how tropical glaciers are impacted by climate change. Full article

(This article belongs to the Special Issue The Role of Snow in High-Mountain Hydrologic Cycle)

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13 pages, 1903 KiB

Open AccessArticle

Efficiency of Treated Domestic Wastewater to Irrigate Two Rice Cultivars, PK 386 and Basmati 515, under a Hydroponic Culture System

by Tahira Aslam, Safdar A. Mirza, Aneeba Rashid, Muhammad Arshad Javed and Luiza C. Campos

Water 2023, 15(17), 3149; https://doi.org/10.3390/w15173149 - 3 Sep 2023

Cited by 1 | Viewed by 1862

Abstract

The increasing human population continues to exert pressure on the freshwater scarcity. The availability of freshwater for crop irrigation has become challenging. The present study aimed to use domestic wastewater (DWW) for the irrigation of two rice cultivars (CVs) after treatment with the [...] Read more.

The increasing human population continues to exert pressure on the freshwater scarcity. The availability of freshwater for crop irrigation has become challenging. The present study aimed to use domestic wastewater (DWW) for the irrigation of two rice cultivars (CVs) after treatment with the bacterial strain Alcaligenes faecalis MT477813 under a hydroponic culture system. The first part of this study focused on the bioremediation and analysis of the physicochemical parameters of DWW to compare pollutants before and after treatment. The biotreatment of DWW with the bacterial isolate showed more than 90% decolourisation, along with a reduction in contaminants. The next part of the study evaluated the impacts of treated and untreated DWW on the growth of two rice cultivars, i.e., PK 386 and Basmati 515, under a hydroponic culture system which provided nutrients and water to plants with equal and higher yields compared to soil. Growth parameters such as the shoot and root length and the wet and dry weights of the rice plants grown in the treated DWW were considerably higher than those for the plants grown in untreated DWW. Therefore, enhanced growth of both rice cultivars grown in biotreated DWW was observed. These results demonstrate the bioremediation efficiency of the bacterial isolate and the utility of the DWW for rice crop irrigation subsequent to biotreatment. Full article

(This article belongs to the Special Issue Recent Advances in Water and Wastewater Treatment)

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18 pages, 5975 KiB

Open AccessArticle

Study on the Mechanism of Rainfall-Runoff Induced Nitrogen and Phosphorus Loss in Hilly Slopes of Black Soil Area, China

by Tienan Li, Fang Ma, Jun Wang, Pengpeng Qiu, Ning Zhang, Weiwei Guo, Jinzhong Xu and Taoyan Dai

Water 2023, 15(17), 3148; https://doi.org/10.3390/w15173148 - 3 Sep 2023

Cited by 3 | Viewed by 2034

Abstract

In order to identify the effects of the slope and precipitation intensity on the soil runoff depth and runoff rate, different tillage patterns (slope-ridge direction, horizontal slope-ridge direction, no-ridge farming) and different slopes (3° and 5°) were set up, and five typical rainfalls [...] Read more.

In order to identify the effects of the slope and precipitation intensity on the soil runoff depth and runoff rate, different tillage patterns (slope-ridge direction, horizontal slope-ridge direction, no-ridge farming) and different slopes (3° and 5°) were set up, and five typical rainfalls from June to September 2021 were selected, to dynamically monitor the soil-erosion dynamics of the test plots under different rainfall intensities. The results show that cross-slope-ridge cropping has a retention effect on runoff, which effectively inhibits the ineffective loss of rainfall confluence. Among these results, the variation range in the soil runoff depth under cross-slope-ridge treatment conditions was 0.11~0.94 mm, while that under the slope-ridge treatment and no-ridge treatment conditions was increased to 1.44~12.49 mm and 3.45~14.96 mm, respectively. It found that the loss of soil nutrients was significantly higher in the slope-ridge direction and in the no-ridge farming condition than in the horizontal slope-ridge direction. It is worth noting that, as the slope of the cultivated land increases, the erosive capacity of the precipitation runoff for the soil phosphorus increases, while the carrying capacity of the soil nitrogen decreases, and the correlation analysis results confirm that the corresponding relationship between the free diffusion capacity of the soil ammonium nitrogen and soil erosion is weaker than that between the nitrate nitrogen and soil erosion. The effects of single factors, such as the slope, ridge direction, and precipitation intensity of the cultivated land, have a significant impact on the soil water- and fertilizer-loss process, while the influence effect of the multi-factor coupling process on soil erosion is weakened. It was confirmed that the erosion process of rainfall runoff on soil nitrogen and phosphorus loss in slope cultivated land is the result of multi-factor action, and the artificial modification of the tillage mode can effectively regulate the effect of farmland water and fertilizer loss. Full article

(This article belongs to the Special Issue Identification and Quantification of Water Flow and Solute Transport Processes in Agricultural, Natural and Artificial Hillslopes)

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Figure 1
Location of the study area. Full article ">Figure 2
The experimental plots and sediment collection device. (A–C) represents cross-ridge, no-ridge, and along-the-ridge plots; (D–F) represents the precipitation and sediment collection devices. Full article ">Figure 3
Analysis of the soil erosion effect under precipitation conditions. Note: (a) the runoff depth at a 3° slope; (b) the soil erosion at a 3° slope; (c) the depth of runoff at a slope of 5°; and (d) the soil loss at a slope of 5°. The different letters indicate significant differences of soil runoff depth and sediment yield (p < 0.05). Full article ">Figure 4
Analysis of the soil nitrogen loss effect. Note: (a) the soil ammonium nitrogen loss at a 3° slope; (b) the soil nitrate nitrogen loss at a slope of 3°; (c) the total soil nitrogen loss at a 3° slope; (d) the soil ammonium nitrogen loss at a slope of 5°; (e) the soil nitrate nitrogen loss at a slope of 5°; and (f) the total soil nitrogen loss at a slope of 5°. The different letters indicate significant differences of soil nitrogen content (p < 0.05). Full article ">Figure 5
Analysis of the soil phosphorus loss effect. Note: (a) the soil particulate phosphorus loss at a slope of 3°; (b) the total soil phosphorus loss at a 3° slope; (c) the soil particulate phosphorus loss at a slope of 5°; and (d) the total soil phosphorus loss at a 5° slope. The different letters indicate significant differences of soil phosphorus content (p < 0.05). Full article ">Figure 6
The synergistic effect between soil erosion and soil fertility diffusion. Note: (a) the relationship curve between soil nitrogen loss and runoff; (b) the relationship curve between soil phosphorus loss and runoff; (c) the relationship curve between soil nitrogen loss and soil loss; and (d) the relationship curve between soil phosphorus loss and soil loss. “**” represents that the fitting degree passes the significance test of p < 0.01; “*” represents that the fitting degree passes the significance test of p < 0.05. Full article ">Figure 7
Characteristics of runoff reduction rates with the rainfall duration. Note: (a) the soil runoff reduction at a slope of 3°; (b) the soil runoff reduction at a slope of 5°. Full article ">Figure 8
Characterization of the rainfall erosion forces. Note: (a) runoff shear; (b) flow power; and (c) unit flow power. The different letters indicate significant differences of rainfall erosion forces (p < 0.05). Full article ">

12 pages, 2053 KiB

Open AccessArticle

Can Selenium Be Removed in a Pilot Plant for Biological Iron and Manganese Removal?

by Andrea Steuer, Urs Dippon-Deißler, Daniel Mahringer and Aki S. Ruhl

Water 2023, 15(17), 3147; https://doi.org/10.3390/w15173147 - 2 Sep 2023

Viewed by 1774

Abstract

Selenium (Se) is essential to human health, yet harmful in high doses. Of the water-soluble Se redox species, Se(IV) readily adsorbs onto iron and aluminium oxides. Se(VI), the dominant form in oxygenated waters, is more mobile and less readily adsorbed. In this study, [...] Read more.

Selenium (Se) is essential to human health, yet harmful in high doses. Of the water-soluble Se redox species, Se(IV) readily adsorbs onto iron and aluminium oxides. Se(VI), the dominant form in oxygenated waters, is more mobile and less readily adsorbed. In this study, the removal of Se(VI) by reduction with Fe(II) to Se(IV) and subsequent adsorption onto iron hydroxides is investigated in a pilot plant for biological iron and manganese removal from groundwater to investigate an economical approach for Se removal during drinking water production. While Se(IV) is removed by up to 90%, Se(VI) shows no removal over 48 h. In batch-shaking tests, the adsorption of Se(IV) and Se(VI) onto iron hydroxides with and without addition of Fe(II) or dithionite as reducing agents was studied. Se(IV) was removed to a greater extent by adsorption than Se(VI) (7% and 2.6%, respectively, at a starting concentration of 0.1 mg/L) and the addition of reducing agents resulted in no significantly higher removal of Se(VI). Reducing Se(VI) with Fe(II) or dithionite and consequent adsorption onto iron hydroxides can therefore be excluded as viable removal mechanism for Se(VI). Full article

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Figure 1
Simplified scheme of the pilot plant with dosing points for Se(VI) or Se(IV) and optional Fe(II), which was only dosed when Se(VI) removal was examined. Numbers depict the sampling ports. Full article ">Figure 2
Pourbaix diagram of soluble Se species in an open system, computed with Lawrence Livermore National Laboratory dataset (llnl.dat). Dark grey field is Se(VI), light grey field is Se(IV), and white field is Se(-II). Full article ">Figure 3
Se(VI) concentrations in the pilot plant after dosing of Se(VI). Error bars indicate minimum and maximum concentrations from duplicate samplings per sampling point. Full article ">Figure 4
Se (top) and Fe (bottom) concentrations in the pilot plant after dosing of Se(VI) and Fe(II). Error bars indicate minimum and maximum concentrations from duplicate samplings per sampling point. Full article ">Figure 5
Se (top) and Fe (bottom) concentrations in the pilot plant after dosing of Se(VI). Fe(II) was provided from anoxic groundwater. Full article ">Figure 6
Se adsorption onto iron hydroxides in the presence of reducing agents for Se(IV) (blue) and Se(VI) (green) removals at Se starting concentrations of 0.1 mg/L (left) and 1.0 mg/L (right). Error bars indicate minimum and maximum values of two replicates. Full article ">

19 pages, 7810 KiB

Open AccessArticle

Effects of Chemical Activation Conditions on Hierarchical Porous Carbon via Oxytetracycline Adsorption

by Fernando Oscar Hayrera, Do-Gun Kim and Seok-Oh Ko

Water 2023, 15(17), 3146; https://doi.org/10.3390/w15173146 - 2 Sep 2023

Cited by 2 | Viewed by 1890

Abstract

This study investigated the characteristics and oxytetracycline (OTC) adsorption of hierarchical porous carbons (HPCs) synthesized under different activation conditions using biomass wheat flour (WF) and NaHCO₃ as an activator. It was found that the characteristics of the HPCs, such as specific surface [...] Read more.

This study investigated the characteristics and oxytetracycline (OTC) adsorption of hierarchical porous carbons (HPCs) synthesized under different activation conditions using biomass wheat flour (WF) and NaHCO₃ as an activator. It was found that the characteristics of the HPCs, such as specific surface area, total and mesopore volume, defects, and crystallinity, were highly dependent on the activation temperature, the dose of the activator, and activation time. In particular, the adsorption mechanisms and adsorption capacity were dominantly governed by the degree of defects in graphitic structures and mesoporosity, which are largely determined by the dose of the activator and the activation temperature. The best OTC adsorption was achieved with the HPC of the most abundant mesopores, which was prepared at 900 °C, a WF:NaHCO₃ mass ratio of 1:1, and a duration of 2 h (HPC900_R1.0_2H). Based on the results of the experiments concerning adsorption kinetics, equilibrium adsorption, and the effects of pH, OTC adsorption onto HPC900_R1.0_2H was monolayer in type, homogeneous, governed by the combination of diffusion and chemisorption, and largely attributed to π–π electron–donor–acceptor interactions and electrostatic interactions. The thermodynamic parameters suggest that it is spontaneous and endothermic. These findings provide valuable information about the design and synthesis of HPCs from biomass, which exhibit optimized properties for the adsorption of refractory organic pollutants. Full article

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

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20 pages, 4810 KiB

Open AccessArticle

Water Heating Systems Performance in Multi-Family Residential Buildings in Brazil

by Juliana May Sangoi, Taylana Piccinini Scolaro and Enedir Ghisi

Water 2023, 15(17), 3145; https://doi.org/10.3390/w15173145 - 2 Sep 2023

Cited by 1 | Viewed by 1881

Abstract

The performance of water heating systems must be evaluated considering energy consumption and efficiency in storing and distributing hot water, together with building and climate characteristics. This work aims to analyse the performance of different water heating systems compared to electric showers, which [...] Read more.

The performance of water heating systems must be evaluated considering energy consumption and efficiency in storing and distributing hot water, together with building and climate characteristics. This work aims to analyse the performance of different water heating systems compared to electric showers, which are widely used in Brazil. Systems with individual gas heaters and solar heaters with electric backup and gas backup were analysed in multi-family buildings. In addition, the influence of thermal insulation of hot water pipes was verified. The analyses were conducted using the EnergyPlus programme, considering three Brazilian cities with different climates: Curitiba, Brasília, and Belém. The results showed that solar heaters are a low primary energy consumption alternative, especially if combined with gas heaters. However, electric showers are the most efficient option for larger buildings and cold-climate cities, where thermal losses in distribution are more significant. Monthly, an electric shower can save up to 1.82 kWh/m² of electricity compared to a solar heating system with an electric backup. The insulation has a limited influence on the performance of short-length pipes (temperature difference less than 0.3 °C in the instantaneous gas system). For longer pipes, the absence of insulation significantly reduces the shower temperature (up to 2.47 °C in solar heating systems), mainly in cold-climate locations. It is concluded that the most suitable water heating system should be determined according to the climate and characteristics of the buildings, such as the size and length of the pipe. Full article

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12 pages, 239 KiB

Open AccessArticle

(Re-)Envisioning Natural Resource Management Involving First Nations: Toward an Effective Co-Management Policy

by Corey McKibbin

Water 2023, 15(17), 3144; https://doi.org/10.3390/w15173144 - 2 Sep 2023

Viewed by 2335

Abstract

In this paper, I posit a relationship between what I consider to be two distinct views of natural resource management: the reductionist and holistic views. The purpose of this comparison is to highlight the dangers of reducing environmental management to its ability to [...] Read more.

In this paper, I posit a relationship between what I consider to be two distinct views of natural resource management: the reductionist and holistic views. The purpose of this comparison is to highlight the dangers of reducing environmental management to its ability to bolster a nation’s economic status. Part of the problem with this view is that it cannot take seriously the needs and desires of Indigenous persons. As such, I compare the reductionist view with the holistic view. The holistic view does not only consider the economics of natural resources; unlike the reductionist view, it aims to take seriously the needs and desires of Indigenous communities that have used natural resources in their territories since time immemorial. To illustrate the differences between the reductionist and holistic views, I examine at length the case of the James Bay Hydro Development in Quebec, Canada. I then apply these insights to an international context by utilizing the literature from Australia. The literature from both Canada and Australia implies that natural resource management involving First Nations needs to take a holistic approach to water management and policy such that the hopes, needs, and desires of Indigenous communities are not merely placated, but fulfilled. Full article

(This article belongs to the Special Issue Conflict and Cooperation: The Duality of Cross-Border Water Governance)

23 pages, 5020 KiB

Open AccessArticle

Interpreting Seasonal Patterns and Long-Term Changes of Zooplankton in a Deep Subalpine Lake Using Stable Isotope Analysis

by Rossana Caroni, Roberta Piscia, Gary Free and Marina Manca

Water 2023, 15(17), 3143; https://doi.org/10.3390/w15173143 - 2 Sep 2023

Cited by 1 | Viewed by 1688

Abstract

The purpose of this study was to elucidate the patterns and mechanisms driving seasonal and interannual variations of carbon and nitrogen stable isotopes in the zooplankton crustacean community of Lake Maggiore (Italy), during the period 2009–2020. Different zooplankton taxa and groups showed different [...] Read more.

The purpose of this study was to elucidate the patterns and mechanisms driving seasonal and interannual variations of carbon and nitrogen stable isotopes in the zooplankton crustacean community of Lake Maggiore (Italy), during the period 2009–2020. Different zooplankton taxa and groups showed different ranges of δ¹³C signatures, giving an insight into food sources and niche partition. In particular, cyclopoids had a restricted range with more negative δ¹³C‰ values and an increase in δ¹³C fractionation with the establishment of water thermal vertical stratification, highlighting the importance of vertical distribution as a key factor for taxa coexistence in a vertically heterogenous environment. The δ¹³C values of the zooplankton community and of Daphnia were positively related to water temperature (R² = 0.58 p < 0.0001 and R² = 0.68 p < 0.0001, respectively), and the δ¹³C Daphnia signature was positively related to chlorophyll a (R² = 0.32, p < 0.0001). Decomposition of the time-series data for zooplankton carbon and nitrogen signatures and environmental parameters identified increasing trends in water temperature, chlorophyll a and water conductivity and a decrease in nitrate that matched changes in carbon isotopic signature trends in some zooplankton taxa (Bosmina, Daphnia and Diaptomids). Overall, the observed patterns in zooplankton isotopic signatures were interpreted as integrations of the effects of climate warming in Lake Maggiore, affecting both the availability of food sources and environmental conditions. Full article

(This article belongs to the Special Issue Biodiversity and Functionality of Plankton Communities)

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17 pages, 3592 KiB

Open AccessArticle

Characteristics of Hydrological and Meteorological Drought Based on Intensity-Duration-Frequency (IDF) Curves

by Ahmad Abu Arra and Eyüp Şişman

Water 2023, 15(17), 3142; https://doi.org/10.3390/w15173142 - 1 Sep 2023

Cited by 17 | Viewed by 3028 | Correction

Abstract

As a catastrophic phenomenon, drought has destructive impacts on water resources, the environment, and the ecosystem. Consequently, drought plays a vital role in risk assessment, water resources management, and drought mitigation plans. The main aim of this research is to obtain critical intensity-duration-frequency [...] Read more.

As a catastrophic phenomenon, drought has destructive impacts on water resources, the environment, and the ecosystem. Consequently, drought plays a vital role in risk assessment, water resources management, and drought mitigation plans. The main aim of this research is to obtain critical intensity-duration-frequency (IDF) drought curves and to provide a comprehensive understanding of the drought characteristics by considering the meteorological Standardized Precipitation Index (SPI), Standardized Precipitation Evapotranspiration Index (SPEI), and hydrological Standardized Streamflow Index (SSI). Critical IDF curves for the drought index and return period selection are identified. Also, new terms are defined as the specific drought duration, the maximum drought duration, and the critical intensity based on drought IDF curves. The results show that the SPI3 based on run theory for 500 years return period has higher drought intensity compared with other drought indices. In some IDF curves, the 2-year return period of a 12-month duration timescale is not provided. Regarding the maximum drought duration, the SPEI12 gave a longer duration. With the new concepts in this research, the presented IDF drought methodology has a novel additional practice to identify the critical intensity and maximum drought duration. Using this methodology for any drought index will contribute to converting data with mathematical calculations into IDF curves for design and risk assessment purposes. Full article

(This article belongs to the Special Issue Drought Occurrences, Characteristics, Impacts and Mitigations)

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12 pages, 2681 KiB

Open AccessEditor’s ChoiceArticle

A Probabilistic Analysis of Drought Areal Extent Using SPEI-Based Severity-Area-Frequency Curves and Reanalysis Data

by Nunziarita Palazzolo, David J. Peres, Brunella Bonaccorso and Antonino Cancelliere

Water 2023, 15(17), 3141; https://doi.org/10.3390/w15173141 - 1 Sep 2023

Cited by 6 | Viewed by 1956

Abstract

Assessing and monitoring the spatial extent of drought is of key importance to forecasting the future evolution of drought conditions and taking timely preventive and mitigation measures. A commonly used approach in regional drought analysis involves spatially interpolating meteorological variables (e.g., rainfall depth [...] Read more.

Assessing and monitoring the spatial extent of drought is of key importance to forecasting the future evolution of drought conditions and taking timely preventive and mitigation measures. A commonly used approach in regional drought analysis involves spatially interpolating meteorological variables (e.g., rainfall depth during specific time intervals, deviation from long-term average rainfall) or drought indices (e.g., Standardized Precipitation Index, Standardized Precipitation Evapotranspiration Index) computed at specific locations. While plotting a drought descriptor against the corresponding percentage of affected areas helps visualize the historical extent of a drought, this approach falls short of providing a probabilistic characterization of the severity of spatial drought conditions. That can be overcome by identifying drought Severity-Area-Frequency (SAF) curves over a region, which establishes a link between drought features with a chosen probability of recurrence (or return period) and the corresponding proportion of the area experiencing those drought conditions. While inferential analyses can be used to estimate these curves, analytical approaches offer a better understanding of the main statistical features that drive the spatial evolution of droughts. In this research, a technique is introduced to mathematically describe the Severity-Area-Frequency (SAF) curves, aiming to probabilistically understand the correlation between drought severity, measured through the SPEI index, and the proportion of the affected region. This approach enables the determination of the area’s extent where SPEI values fall below a specific threshold, thus calculating the likelihood of observing SAF curves that exceed the observed one. The methodology is tested using data from the ERA5-Land reanalysis project, specifically studying the drought occurrences on Sicily Island, Italy, from 1950 to the present. Overall, findings highlight the improvements of incorporating the spatial interdependence of the assessed drought severity variable, offering a significant enhancement compared to the traditional approach for SAF curve derivation. Moreover, they validate the suitability of reanalysis data for regional drought analysis. Full article

(This article belongs to the Special Issue Drought Monitoring and Risk Assessment)

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Scheme illustrating the proposed approach for probabilistically characterizing the spatial extent of drought and deriving SAF curves based on SPEI. Full article ">Figure 2
Elevation map of Sicily Island and related ERA5-Land grid. Full article ">Figure 3
Spatial averaged SPEI values from 1950 to the present considering the 12-month aggregation time scale. Full article ">Figure 4
Severity-Area curves referred to three different years where dry, normal and wet conditions occurred. Full article ">Figure 5
Probability plot of the observed <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>A</mi> </mrow> <mrow> <mi>d</mi> <mo>,</mo> <mi>t</mi> </mrow> </msub> <mo>(</mo> <msub> <mrow> <mi>z</mi> </mrow> <mrow> <mn>0</mn> </mrow> </msub> <mo>)</mo> </mrow> </semantics></math> vs. the corresponding quantiles computed using the derived distributions. Full article ">Figure 6
SAF curves and observed Severity-Area curves for three experienced events in terms of drought conditions. Full article ">

20 pages, 5972 KiB

Open AccessArticle

A Hybrid Theory-Driven and Data-Driven Modeling Method for Solving the Shallow Water Equations

by Shunyu Yao, Guangyuan Kan, Changjun Liu, Jinbo Tang, Deqiang Cheng, Jian Guo and Hu Jiang

Water 2023, 15(17), 3140; https://doi.org/10.3390/w15173140 - 1 Sep 2023

Cited by 2 | Viewed by 1659

Abstract

In recent years, mountainous areas in China have faced frequent geological hazards, including landslides, debris flows, and collapses. Effective simulation of these events requires a solver for shallow water equations (SWEs). Traditional numerical methods, such as finite difference and finite volume, face challenges [...] Read more.

In recent years, mountainous areas in China have faced frequent geological hazards, including landslides, debris flows, and collapses. Effective simulation of these events requires a solver for shallow water equations (SWEs). Traditional numerical methods, such as finite difference and finite volume, face challenges in discretizing convection flux terms, while theory-based models need to account for various factors such as shock wave capturing and wave propagation direction, demanding a high-level understanding of the underlying physics. Previous deep learning (DL)-based SWE solvers primarily focused on constructing direct input–output mappings, leading to weak generalization properties when terrain data or stress constitutive relations change. To overcome these limitations, this study introduces a novel SWE solver that combines theory and data-driven methodologies. The core idea is to use artificial neural networks to compute convection flux terms, and to reduce modeling complexity. Theory-based modeling is used to tackle complex terrain and friction terms for the purpose of ensuring generalization. Our method surpasses challenges faced by previous DL-based solvers in capturing terrain and stress variations. We validated our solver’s capabilities by comparing simulation results with analytical solutions, real-world disaster cases, and the widely used Massflow software-generated simulations. This comprehensive comparison confirms our solver’s ability to accurately simulate hazard scenarios and showcases strong generalization on varying terrain and land surface friction. Our proposed method effectively addresses DL-based solver limitations while simplifying the complexities of theory-driven numerical methods, offering a promising approach for hazard dynamics simulation. Full article

(This article belongs to the Special Issue Advances in Flood and Drought Disaster Forecasting and Early Warnings through Integrating Hydrological and Hydrodynamic Models)

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16 pages, 2608 KiB

Open AccessArticle

A Simplified Method for Effective Calculation of 3D Slope Reliability

by Juxiang Chen, Dayong Zhu and Yalin Zhu

Water 2023, 15(17), 3139; https://doi.org/10.3390/w15173139 - 1 Sep 2023

Viewed by 1489

Abstract

Traditional 3D slope reliability analysis methods have high computational costs and are difficult to popularize in engineering practice. Under the framework of the limit equilibrium method with 3D slip surface normal stress correction, the critical horizontal acceleration coefficient

K_{c}

, which is [...] Read more.

Traditional 3D slope reliability analysis methods have high computational costs and are difficult to popularize in engineering practice. Under the framework of the limit equilibrium method with 3D slip surface normal stress correction, the critical horizontal acceleration coefficient

K_{c}

, which is equivalent to the safety factor

F_{s}

, is selected to characterize the slope stability. The limit state function uses the difference between

K_{c}

and the known critical value

K_{c 0}

. A simplified method for calculating the reliability of 3D slope is proposed. Through two typical slope examples, the 3D reliability calculation results of six methods after coupling two limit state functions and three reliability algorithms are compared. The results show that this method is reliable and effective, and the method coupled with subset simulation (SS) is the one with good calculation accuracy and efficiency. In the case of long slopes, 2D analysis results may underestimate the probability of slope instability, and 3D reliability of the slope must be analyzed. Full article

(This article belongs to the Special Issue Risk Management Technologies for Deep Excavations in Water-Rich Areas)

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17 pages, 3239 KiB

Open AccessArticle

Heavy Metal Distribution Characteristics, Water Quality Evaluation, and Health Risk Evaluation of Surface Water in Abandoned Multi-Year Pyrite Mine Area

by Yiwen Jiao, Yitian Liu, Wei Wang, Yujiao Li, Wentong Chang, Ao Zhou and Ronglong Mu

Water 2023, 15(17), 3138; https://doi.org/10.3390/w15173138 - 1 Sep 2023

Cited by 7 | Viewed by 2745

Abstract

Acid mine drainage (AMD) is a major anthropogenic source of heavy metal discharge worldwide. However, little research has been carried out on the development of AMD in abandoned pyrite mines and the heavy metal contamination of mine surface water. The aim of this [...] Read more.

Acid mine drainage (AMD) is a major anthropogenic source of heavy metal discharge worldwide. However, little research has been carried out on the development of AMD in abandoned pyrite mines and the heavy metal contamination of mine surface water. The aim of this study was to investigate and assess heavy metal pollution in three streams within an abandoned pyrite mine area in southeastern Shaanxi Province, China. Surface water pollution was assessed using the pollution index assessment method and the health risk assessment model. The results showed that the combined heavy metal pollution indices of the surveyed rivers were Tielu Creek (4699.227), Jiancao Creek (228.840), and Daoban Creek (68.106). After multivariate statistical analysis, it was found that the tailings slag and mine chamber in the abandoned mine area were the main causes of AMD, and AMD posed a serious risk of heavy metal pollution to the surrounding waters. The risk of carcinogenicity of heavy metals is also quite high in the surface water of mining area. Therefore, there is an urgent need to ecologically manage heavy metal pollution from abandoned mine sites, and this study provides insights into understanding heavy metal pollution in the aquatic environment of abandoned mine sites. Full article

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21 pages, 4287 KiB

Open AccessArticle

Evaluation of Regional Water Ecological Economic System Sustainability Based on Emergy Water Ecological Footprint Theory—Taking the Yellow River Basin as an Example

by Zening Wu, Xiangyu Chen and Danyang Di

Water 2023, 15(17), 3137; https://doi.org/10.3390/w15173137 - 31 Aug 2023

Cited by 1 | Viewed by 1342

Abstract

In the article, on the basis of quantifying the emergy water ecological footprint, a sustainability evaluation system for the overall water ecological economic system of the basin and each province (region) was proposed. And using the subjective and objective combination of the Analytic [...] Read more.

In the article, on the basis of quantifying the emergy water ecological footprint, a sustainability evaluation system for the overall water ecological economic system of the basin and each province (region) was proposed. And using the subjective and objective combination of the Analytic Hierarchy Process (AHP) and Entropy Weight Method (EWM) to determine the weight of the indicator system, a TOPSIS model for sustainability evaluation was constructed. And taking the Yellow River Basin as an example, the results indicate that (1) Throughout the entire basin, the sustainability of the water ecological economic system showed a fluctuating upward trend year by year during the study period, from 0.37 to 0.51. (2) In each province (region), the sustainability of the water ecological economic system had gathered in space. The overall sustainability level of the upstream Sichuan, Qinghai and Gansu provinces is high, always at level (I). The overall sustainability level of the midstream Ningxia and Neimenggu was low, always at level (IV). The overall sustainability level of the downstream Shaanxi, Shanxi, Henan and Shandong provinces is high, rising gradually over time, from level (III) to level (II) or (I). Against the backdrop of the rapid development of the economy and society, the contradiction between economic and social development, ecological environment protection, and sustainable utilization of water resources is becoming increasingly severe, which has become a key factor restricting the sustainable development of the ecological economic system in Yellow River Basin. Multidimensional comprehensive evaluation of the sustainability level of the regional water ecological economic system is a prerequisite for identifying sustainable development issues in the Yellow River Basin, and also the basis for formulating targeted policies for sustainable utilization of regional water resources and high-quality economic development. Full article

(This article belongs to the Special Issue Yellow River Basin Management under Pressure: Present State, Restoration and Protection II)

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