Water

18 pages, 9406 KiB

Open AccessArticle

Investigating Seawater Intrusion in Republic of South Africa’s Heuningnes, Cape Agulhas Using Hydrogeochemistry and Seawater Fraction Techniques

by Abongile Xaza, Harold Wilson Tumwitike Mapoma, Tamiru A. Abiye, Sumaya Clarke and Thokozani Kanyerere

Water 2023, 15(11), 2141; https://doi.org/10.3390/w15112141 - 05 Jun 2023

Cited by 2 | Viewed by 1833

Abstract

The Heuningnes Catchment in the Republic of South Africa was used as a case study in this research to describe the application of saltwater fraction/quantification and hydrogeochemistry methods to evaluate the extent of saline intrusion in the coastal aquifers. The argument of the [...] Read more.

The Heuningnes Catchment in the Republic of South Africa was used as a case study in this research to describe the application of saltwater fraction/quantification and hydrogeochemistry methods to evaluate the extent of saline intrusion in the coastal aquifers. The argument of the research is that the presence of seawater incursion may be conclusively determined by combining the examination of the major ions, seawater fraction, stable isotopes of water, bromide, and geochemical modeling. Using stable isotopes of oxygen (¹⁸O) and deuterium (²H), major ions chemistry, seawater composition, and geochemical modeling, the genesis of salinity and mixing of different water masses were examined. Twenty-nine (29) samples of groundwater were examined. All samples showed water facies of the Na-Cl type, indicating a seawater-related origin. The significance of mixing in coastal aquifers under natural conditions was shown by the hydrogeochemical characteristics of key ions derived from ionic ratios, which demonstrated substantial adherence to mixing lines among endmembers for freshwater as well as saltwater (seawater). The quantification of seawater contribution in groundwater percentages varied from 0.01 to 43%, with three samples having concentrations of seawater above 50%. It was clear from the hydrogeochemical analysis and determination of the proportion of saltwater that the seawater intrusion impacted the coastal fresh groundwater. In addition, the chloride concentration in the groundwater ranged from 81.5 to 26,557.5 mg/L, with the corresponding δ¹⁸O values ranging from −5.5‰ to −0.9‰, which suggested that freshwater and saltwater were mixing. The Br⁻/Cl⁻ ratios showed that evaporation had played a part in elevating groundwater salinity as well. Since saturation indices were below zero, the mineral dissolution could also contribute to the salinization of groundwater. Further proof of seawater incursion in the investigated catchment was supplied by geochemical modeling and bromide. Even though such tools were not verified in multiple coastal aquifers for widespread generalization, the study offered a scientifically significant understanding of the application of such tools on seawater intrusion in coastal aquifers and has useful recommendations for the aquifer setting of similar environments. Full article

(This article belongs to the Special Issue Advances on the Dynamics of Groundwater Salinization)

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14 pages, 5284 KiB

Open AccessArticle

Acquisition of Spatial and Temporal Characteristics of Shallow Groundwater Movement Based on Long-Term Temperature Time Series in the Kangding Area, Eastern Tibetan Plateau

by Bo Zhou, Qiongying Liu, Shunyun Chen and Peixun Liu

Water 2023, 15(11), 2140; https://doi.org/10.3390/w15112140 - 05 Jun 2023

Viewed by 1031

Abstract

Heat has been widely used as a groundwater tracer to determine groundwater flow direction and velocity in a way that is ubiquitous, low-cost, environmentally friendly, and easy to use. However, temperature observations are generally short-term and small-scale, meaning they may not be able [...] Read more.

Heat has been widely used as a groundwater tracer to determine groundwater flow direction and velocity in a way that is ubiquitous, low-cost, environmentally friendly, and easy to use. However, temperature observations are generally short-term and small-scale, meaning they may not be able to reflect long-term changes in the characteristics of groundwater movement. In this study, we utilize 515 days of temperature data, collected from four measurement points in the Kangding area of the eastern Tibetan Plateau, in order to determine the spatial and temporal distribution of groundwater flow velocities using different analytical heat tracing methods. An analysis is conducted to evaluate the impact of thermal parameter uncertainties on the calculation of flow velocity, and a comparison is undertaken between the results of the phase, amplitude, and combined amplitude-phase methods. We subsequently discuss the relationship between flow velocity changes and precipitation. The results show that the estimated flow velocity is more susceptible to the volumetric heat capacity of the saturated sediment than it is to thermal conductivity. The phase method is more suitable for use in calculations in the study area, indicating that precipitation significantly impacts the flow velocity and that this impact is more pronounced in areas with flat terrain compared to areas with significant variation in elevation. Our research provides a comparative study of the heat tracing methods in areas with varied terrains and offers new evidence for the impact of precipitation and topography on groundwater infiltration. Full article

(This article belongs to the Special Issue Groundwater–Surface Water Interactions)

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21 pages, 5536 KiB

Open AccessArticle

Multifrequency Downstream Hydraulic Geometry of Alluvial Mountain Rivers Located on the Qinghai–Tibet Plateau

by Chao Qin, Baosheng Wu, Yuan Xue, Xudong Fu, Guangqian Wang and Ge Wang

Water 2023, 15(11), 2139; https://doi.org/10.3390/w15112139 - 05 Jun 2023

Cited by 1 | Viewed by 1061

Abstract

Downstream hydraulic geometry (DHG) for multiple discharge frequencies remains poorly investigated. This paper seeks to clarify the DHG relations of different discharge frequencies and proposes the definition, mathematical expression, and geomorphological interpretation of multifrequency DHG (MFDHG). It also verifies the existence of DHG [...] Read more.

Downstream hydraulic geometry (DHG) for multiple discharge frequencies remains poorly investigated. This paper seeks to clarify the DHG relations of different discharge frequencies and proposes the definition, mathematical expression, and geomorphological interpretation of multifrequency DHG (MFDHG). It also verifies the existence of DHG and MFDHG in the six major exoreic rivers located in the Qinghai–Tibet Plateau. MFDHG can be depicted with (1) log-linear plots between DHG coefficients and exponents for multiple discharge frequencies and (2) independent DHG curves intersecting near congruent discharge, width, depth, or velocity. The results show that rivers in the study area exhibit strong DHG relations. The variations in the DHG coefficients and exponents usually exhibit opposite trends with increasing discharge frequency. The MFDHG of a river reach is generally stronger than that of a river basin. Congruent hydraulics, as indices of geometric variability and hydraulic self-similarity, reflect consistent changes in hydraulic variables downstream. MFDHG is a novel geomorphic phenomenon that bridges spatiotemporal dimensions in HG systems and provides a basis for establishing an overall HG relationship. Full article

(This article belongs to the Topic Research on River Engineering)

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18 pages, 5787 KiB

Open AccessArticle

Measuring and Evaluating the Speed and the Physical Characteristics of Fishes Based on Video Processing

by Faezeh Behzadi Pour, Lorena Parra, Jaime Lloret and Saman Abdanan Mehdizadeh

Water 2023, 15(11), 2138; https://doi.org/10.3390/w15112138 - 05 Jun 2023

Viewed by 1228

Abstract

Acquiring the morphological parameters of fish with the traditional method (depending on human and non-automatic factors) not only causes serious problems, such as disease transmission, mortality due to stress, and carelessness and error, but it is also time-consuming and has low efficiency. In [...] Read more.

Acquiring the morphological parameters of fish with the traditional method (depending on human and non-automatic factors) not only causes serious problems, such as disease transmission, mortality due to stress, and carelessness and error, but it is also time-consuming and has low efficiency. In this paper, the speed of fish and their physical characteristics (maximum and minimum diameter, equivalent diameter, center of surface, and velocity of fish) were investigated by using a programmed online video-recording system. At first, using the spatial coordinates obtained from YOLOv2, the speed of the fish was calculated, and the morphological characteristics of the fish were also recorded using this program during two stages of feeding and normal conditions (when the fish are not in feeding condition). Statistical analysis was performed between the measured parameters due to the high correlation between the parameters, and the classification system with high accuracy was able to provide an accurate prediction of the fish in both normal and feeding conditions. In the next step, an artificial neural network (ANN) prediction model (with three neurons; four input, one hidden layer, and one output) was presented to plan the system online. The model has the lowest error (1.4 and 0.14, respectively) and the highest coefficient of explanation (0.95 and 0.94, respectively) in two modes, normal and feeding, which are presented by the ANN system for planning the online system. The high accuracy and low error of the system, in addition to having a high efficiency for continuous and online monitoring of live fish, can have a high economic benefit for fish breeders due to the simplicity of its equipment, and it can also check and diagnose the condition of fish in time and prevent economic damage. Full article

(This article belongs to the Section Water, Agriculture and Aquaculture)

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19 pages, 1191 KiB

Open AccessReview

Phytoplankton Carbon Utilization Strategies and Effects on Carbon Fixation

by Xin Wang, Zhuo Yin, Jielai Chen and Jing Liu

Water 2023, 15(11), 2137; https://doi.org/10.3390/w15112137 - 05 Jun 2023

Cited by 1 | Viewed by 4500

Abstract

Phytoplankton have a crucial role in the conversion of greenhouse gas sources and sinks in natural water bodies, such as lakes, rivers, and oceans. In response to environmental changes, phytoplankton adapt by altering their carbon utilization strategies, which affect carbon fixation rates and [...] Read more.

Phytoplankton have a crucial role in the conversion of greenhouse gas sources and sinks in natural water bodies, such as lakes, rivers, and oceans. In response to environmental changes, phytoplankton adapt by altering their carbon utilization strategies, which affect carbon fixation rates and carbon fluxes at the water–air interface. This paper classifies and summarizes the main carbon utilization strategies of phytoplankton in terms of carbon acquisition, carbon metabolism, and carbon emission. Their carbon acquisition strategy determines their carbon uptake rate, while their carbon metabolism strategy affects their carbon fixation potential. Moreover, their carbon emission strategy determines the final net carbon fixation. A systematic study of phytoplankton carbon utilization strategies is important for the development of phytoplankton-based wastewater treatment technologies, understanding of algal greenhouse gas fixation, and assessment of greenhouse gas sources and sinks in natural water bodies. This article provides a comprehensive understanding of the ecological role of phytoplankton in natural water bodies and offers valuable references for related research. Furthermore, our research sheds light on the carbon metabolism and emission processes of phytoplankton. By analyzing the carbon metabolism and emission of phytoplankton under different carbon utilization strategies, we can more accurately evaluate the impact of phytoplankton on the carbon cycle in natural water bodies, which can contribute to environmental protection and sustainable development. Full article

(This article belongs to the Topic Carbon-Energy-Water Nexus in Global Energy Transition)

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13 pages, 5515 KiB

Open AccessArticle

Analysis of Resource Potential of Emergent Aquatic Vegetation in the Curonian Lagoon of the Baltic Sea

by Yuliya Kulikova, Julia Gorbunova, Sergey Aleksandrov, Marina Krasnovskih, Valentin Gurchenko and Olga Babich

Water 2023, 15(11), 2136; https://doi.org/10.3390/w15112136 - 05 Jun 2023

Viewed by 1293

Abstract

This paper presents results of an aquatic vegetation resource potential assessment. The study is aimed at assessing the perspective of biotechnological approaches to reducing the biogenic pollution of water bodies by the removal of aquatic vegetation. The article analyzes the dominant species of [...] Read more.

This paper presents results of an aquatic vegetation resource potential assessment. The study is aimed at assessing the perspective of biotechnological approaches to reducing the biogenic pollution of water bodies by the removal of aquatic vegetation. The article analyzes the dominant species of aquatic vegetation in the Curonian Lagoon, and their productivity and resource potential. It was established that the concentrations of protein and fat in the biomass of four dominant plants are extremely low, making it impossible to speak of their values in terms of biomass processing. Based on elemental composition, we can conclude that the biomass of Phragmites australis should have a high calorie content because it has a high carbon and hydrogen content (49.6% and 7.1%, respectively), resulting in a high energy value. Synchronous thermal analysis revealed that the maximum energy values of biomasses of Phragmites australis and Scirpus lacustris have a net calorific value of 12.62 and 12.55 MJ/kg, respectively. At the same time, the biomass of these plants has a low ash content (around 6.6–7.6%) and a low sulfur content (less than 0.41%). An analysis of the composition of aquatic vegetation biomass samples allowed us to establish that, given the permissible collection time (no earlier than September), the search for directions in the utilization of aquatic vegetation should focus on processing cellulose with the production of crystalline cellulose, biochar, or biofuel via anaerobic digestion. The removal of the excess biomass of aquatic vegetation (Phragmites australis) will allow the reduction of the nitrogen and phosphorus load in the water body by 140 kg/ha and 14 kg/ha, respectively. Full article

(This article belongs to the Special Issue Environmental Chemistry of Water Quality Monitoring II)

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17 pages, 3722 KiB

Open AccessArticle

A Prediction Model to Cost-Optimize Clean-Out of Permeable Interlocking Concrete Pavers

by Sachet Siwakoti, Andrew Binns, Andrea Bradford, Hossein Bonakdari and Bahram Gharabaghi

Water 2023, 15(11), 2135; https://doi.org/10.3390/w15112135 - 04 Jun 2023

Viewed by 1668

Abstract

Permeable Interlocking Concrete Paver (PICP) systems provide onsite stormwater management by detaining runoff and removing contaminants. However, a major problem with PICPs is the significant maintenance cost associated with their clean-out to restore the original functionality, which discourages landowners and municipalities from adopting [...] Read more.

Permeable Interlocking Concrete Paver (PICP) systems provide onsite stormwater management by detaining runoff and removing contaminants. However, a major problem with PICPs is the significant maintenance cost associated with their clean-out to restore the original functionality, which discourages landowners and municipalities from adopting the systems. A combination of laboratory experiments and machine-learning techniques are applied to address this challenge. A total of 376 laboratory experiments were conducted to investigate four independent variables (cleaning equipment speed over the pavement, air speed in the cleaning jets, top opening width of the cupule, and filter media gradation) that affect the cleaning of PICPs. The Buckingham Pi-Theorem was used to express the four main input variables in three dimension-less parameters. This current investigation provides a novel understanding of variables affecting the sustainable and economically feasible maintenance of PICPs. A new model is derived to more accurately predict the percentage of mass removal from PICPs during clean-out using a machine-learning technique. The Group Method of Data Handling (GMDH) model exhibits high performance, with a correlation coefficient (R2) of 0.87 for both the training and testing stages. The established simple explicit equation can be applied to optimize the maintenance costs for industrial applications of Regenerative Air Street Sweepers for sustainable and cost-effective PICP maintenance. Pavements with larger surface areas are found to have lower maintenance costs ($/m²/year) compared to the ones with smaller surface areas. This study estimates $0.32/m²/year and $0.50/m²/year to maintain pavements with larger (5000 m²) and smaller (1000 m²) surface areas, respectively. Full article

(This article belongs to the Special Issue Water Quality for Sustainable Development)

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21 pages, 5439 KiB

Open AccessArticle

Plant Photosynthesis and Dry Matter Accumulation Response of Sweet Pepper to Water–Nitrogen Coupling in Cold and Arid Environment

by Hengjia Zhang, Yong Wang, Shouchao Yu, Chenli Zhou, Fuqiang Li, Xietian Chen, Lintao Liu and Yingying Wang

Water 2023, 15(11), 2134; https://doi.org/10.3390/w15112134 - 04 Jun 2023

Cited by 2 | Viewed by 1270

Abstract

In order to optimize the water and nitrogen management mode and realize the efficient scale production of sweet pepper, from 2021 to 2022, field experiments on sweet pepper cultivation with different water and nitrogen coupling modes were conducted in the Hexi Oasis irrigation [...] Read more.

In order to optimize the water and nitrogen management mode and realize the efficient scale production of sweet pepper, from 2021 to 2022, field experiments on sweet pepper cultivation with different water and nitrogen coupling modes were conducted in the Hexi Oasis irrigation areas. The regulation effects of the water–nitrogen coupling mode on the dry matter accumulation characteristics, photosynthesis, yield, and water–nitrogen utilization efficiency of sweet pepper were further discussed. Irrigation was set for full irrigation (W1, 75–85% FC [field capacity]), mild (W2, 65–75% FC), and moderate (W3, 55–65% FC) water deficit levels. Three levels of nitrogen were applied, high (N1, 300 kg·ha⁻¹), medium (N2, 225 kg·ha⁻¹) and low (N3, 150 kg·ha⁻¹), with full irrigation and no nitrogen application used as the control (CK). The results showed that the appropriate water–nitrogen coupling mode could enhance the photosynthetic rate, increase dry matter accumulation and the accumulation rate, advance the days of a maximum rate of dry matter accumulation, and improve yield and water–nitrogen utilization efficiency. N1W1 had the greatest dry matter accumulation, the mean rate and the maximum increase rate of dry matter accumulation in sweet pepper, which was not a significant difference from N2W2, but significantly increased by 19.61%, 19.67%, and 23.45%, respectively, compared with CK. Water deficit significantly advanced the days of a maximum rate of dry matter accumulation. The days of a maximum rate of dry matter accumulation appeared 1.18–5.79 days earlier at W3 than at W2 and W1, and the maximum rate appeared gradually later with increasing irrigation. The net photosynthetic rate, the transpiration rate, and stomatal conductance of N2W2 sweet pepper showed the best performance at all growth stages, significantly increasing by 23.87%, 27.71%, and 27.39%, respectively, compared with CK. Moreover, the Intercellular CO₂ concentration was significantly reduced by 14.77% in N2W2 compared to CK. The N2W2 had the highest yield, water use efficiency, and irrigation water use efficiency of sweet pepper, significantly increasing 26.89%, 33.74%, and 31.22% compared to CK. Excessive water and nitrogen dosage reduced nitrogen partial factor productivity, while an appropriate increase in irrigation under reduced nitrogen conditions facilitated the water nitrogen potential. Passage path analysis further showed that water–nitrogen coupling promotes plant biomass formation and distribution by increasing photosynthetic assimilation capacity, ultimately increasing yield. Therefore, the N2W2 treatment (65–75% FC, 225 kg·ha⁻¹) is the ideal water and nitrogen mode for obtaining higher yields and water and nitrogen use efficiency of sweet pepper in a cold and arid environment. Full article

(This article belongs to the Section Ecohydrology)

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13 pages, 995 KiB

Open AccessArticle

Polylactic Acid-Based Microplastic Particles Induced Oxidative Damage in Brain and Gills of Goldfish Carassius auratus

by Alla Khosrovyan, Hranush Melkonyan, Lilit Rshtuni, Bardukh Gabrielyan and Anne Kahru

Water 2023, 15(11), 2133; https://doi.org/10.3390/w15112133 - 04 Jun 2023

Cited by 2 | Viewed by 2087

Abstract

The effect of 96 h exposure of the goldfish Carassius auratus to two different types of bioplastic particles, originating from commercial shopping bag (Bag, ~5 mm) and polylactic acid-based (PLA) cup (Cup, ≤5 mm), and petroleum-based polyamide particles (PA, 0–180 µm) was studied. [...] Read more.

The effect of 96 h exposure of the goldfish Carassius auratus to two different types of bioplastic particles, originating from commercial shopping bag (Bag, ~5 mm) and polylactic acid-based (PLA) cup (Cup, ≤5 mm), and petroleum-based polyamide particles (PA, 0–180 µm) was studied. All particles were studied as virgin and after simulated UV-degradation (at concentration 30 mg L⁻¹). The experiments were conducted according to OECD 203 test guidelines. The toxicity endpoint evaluated in fish brain and gills was lipid peroxidation (LPO) quantified as nmol thiobarbituric acid reactive substances (TBARs) mg⁻¹ protein. The results indicated that indicatively compostable PLA bioplastic Cup induced significant LPO in the brain and/or gills of the goldfish, in contrast to the particles from Bag and PA (in the brain, Cup > Bag > PA; in the gills, Cup > Bag). The UV-degradation of the particles of all studied types had no significant effect on the LPO level compared to virgin particles. While the increase of LPO in fish gills and brain upon exposure to PLA-plastic particles can be transitory in the long-term perspective, our results point to the necessity of a thorough investigation of the hazard of bioplastics at different state of environmental degradation/weathering. Full article

(This article belongs to the Special Issue The Ecological Effects of Micro(nano)plastics in the Water Environment)

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15 pages, 1098 KiB

Open AccessCommunication

The Reduction of SARS-CoV-2 RNA Concentration in the Presence of Sewer Biofilms

by Shuxin Zhang, Elipsha Sharma, Ananda Tiwari, Yan Chen, Samendra P. Sherchan, Shuhong Gao, Xu Zhou, Jiahua Shi and Guangming Jiang

Water 2023, 15(11), 2132; https://doi.org/10.3390/w15112132 - 04 Jun 2023

Cited by 2 | Viewed by 1911

Abstract

Wastewater surveillance has been widely used to track the prevalence of SARS-CoV-2 in communities. Although some studies have investigated the decay of SARS-CoV-2 RNA in wastewater, understanding about its fate during wastewater transport in real sewers is still limited. This study aims to [...] Read more.

Wastewater surveillance has been widely used to track the prevalence of SARS-CoV-2 in communities. Although some studies have investigated the decay of SARS-CoV-2 RNA in wastewater, understanding about its fate during wastewater transport in real sewers is still limited. This study aims to assess the impact of sewer biofilms on the dynamics of SARS-CoV-2 RNA concentration in naturally contaminated real wastewater (raw influent wastewater without extra SARS-CoV-2 virus/gene seeding) using a simulated laboratory-scale sewer system. The results indicated that, with the sewer biofilms, a 90% concentration reduction of the SARS-CoV-2 RNA was observed within 2 h both in wastewater of gravity (GS, gravity-driven sewers) and rising main (RM, pressurized sewers) sewer reactors. In contrast, the 90% reduction time was 8–26 h in control reactors without biofilms. The concentration reduction of SARS-CoV-2 RNA in wastewater was significantly more in the presence of sewer biofilms. In addition, an accumulation of c.a. 260 and 110 genome copies/cm² of the SARS-CoV-2 E gene was observed in the sewer biofilm samples from RM and GS reactors within 12 h, respectively. These results confirmed that the in-sewer concentration reduction of SARS-CoV-2 RNA in wastewater was likely caused by the partition to sewer biofilms. The need to investigate the in-sewer dynamic of SARS-CoV-2 RNA, such as the variation of RNA concentration in influent wastewater caused by biofilm attachment and detachment, was highlighted by the significantly enhanced reduction rate of SARS-CoV-2 RNA in wastewater of sewer biofilm reactors and the accumulation of SARS-CoV-2 RNA in sewer biofilms. Further research should be conducted to investigate the in-sewer transportation of SARS-CoV-2 and their RNA and evaluate the role of sewer biofilms in leading to underestimates of COVID-19 prevalence in communities. Full article

(This article belongs to the Special Issue Pathogen Detection and Identification in Wastewater)

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Graphical abstract

18 pages, 1941 KiB

Open AccessArticle

Integrated Soundness Assessment of Agricultural Reservoirs Based on Water Quantity and Quality

by Seungwook Lee, Daye Kim, Seungjin Maeng, Eunbi Hong and Hyungkeun Park

Water 2023, 15(11), 2131; https://doi.org/10.3390/w15112131 - 03 Jun 2023

Viewed by 1095

Abstract

For the first time, the results of a comprehensive assessment study on agricultural reservoirs in Korea were obtained. In this study, four agricultural reservoirs in Korea, namely, Songgo, Idam, Nohong, and Jukryang reservoirs, were investigated to establish a quantitative assessment system based on [...] Read more.

For the first time, the results of a comprehensive assessment study on agricultural reservoirs in Korea were obtained. In this study, four agricultural reservoirs in Korea, namely, Songgo, Idam, Nohong, and Jukryang reservoirs, were investigated to establish a quantitative assessment system based on the water quantity and quality of the agricultural reservoirs, and present ratings. The research method involves selecting an indicator framework to evaluate water quantity and quality, using the statistical package for the social sciences statistics analysis program to verify compliance with standards and suitability of the indicator system, and selecting the final indicators to calculate their weights. The Jukryang and Nohong reservoirs have good water quality based on the average grade whereas the Songgo and Idam reservoirs have water quality that requires improvement as per Korean agricultural water standards. The weights of 0.5 were applied to water quantity and quality. Comparison between the entropy method and the principal component analysis showed that the former is suitable as it showed a smaller deviation from the average than the latter one. Thus, the Jukryang reservoir showed the highest integrated soundness index, while the Songgo reservoir showed a lower index. Analysis of all reservoirs might help in establishing a rating system with absolute standards to provide grounds for agricultural reservoirs and diagnose the condition of reservoirs. Full article

(This article belongs to the Section Water, Agriculture and Aquaculture)

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15 pages, 2135 KiB

Open AccessArticle

Study on the Contribution of Land Use and Climate Change to Available Water Resources in Basins Based on Vector Autoregression (VAR) Model

by Mengmeng Jiang, Zening Wu, Xi Guo, Huiliang Wang and Yihong Zhou

Water 2023, 15(11), 2130; https://doi.org/10.3390/w15112130 - 03 Jun 2023

Cited by 2 | Viewed by 1270

Abstract

Under the influence of global climate change and urbanization processes, the number of available water resources (AWRs) in basins has become significantly more uncertain, which has restricted the sustainable development of basins. Therefore, it is important for us to understand the relationship between [...] Read more.

Under the influence of global climate change and urbanization processes, the number of available water resources (AWRs) in basins has become significantly more uncertain, which has restricted the sustainable development of basins. Therefore, it is important for us to understand the relationship between land use (LU) patterns and climate change on AWRs in a basin for sustainable development. To this end, the vector autoregressive (VAR) method was adopted to construct a quantitative model for AWRs in the basin in this study. Taking the Yiluo River Basin (YRB) as an example, the dynamic relationship between the five elements of agricultural land (AD), woodland (WD), grassland (GD), construction land (CD), and annual precipitation (PREP) and AWRs in the basin was studied. The results show the following: (1) The constructed VAR model was stable, indicating that the use of the proposed VAR model to characterize the degree of the effect of LU pattern and PREP on AWRs in the YRB was reasonable and effective. (2) AWRs in the YRB showed a downward trend, and their responses to the change in LU and PREP were delayed. The changes in the AWRs in the YRB tended to occur the year after changes to the LU pattern and PREP occurred. (3) In the long run, the degree of the contribution of each influencing factor to changes to AWRs was 23.76% (AD), 6.09% (PREP), 4.56% (CD), 4.40% (WD), and 4.34% (GD), which meant that the impact of the LU pattern was more than 90%. This study provides new ideas for similar research, water resource allocation, and LU planning in other river basins from a macroscopic perspective. Full article

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

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19 pages, 6862 KiB

Open AccessArticle

Water Quality Sampling and Multi-Parameter Monitoring System Based on Multi-Rotor UAV Implementation

by Rihong Zhang, Zhenhao Wang, Xiaomin Li, Zipeng She and Baoe Wang

Water 2023, 15(11), 2129; https://doi.org/10.3390/w15112129 - 03 Jun 2023

Cited by 2 | Viewed by 2697

Abstract

Water quality sampling and monitoring are fundamental to water environmental protection. The purpose of this study was to develop a water quality sampling and multi-parameter monitoring system mounted on a multi-rotor unmanned aerial vehicle (UAV). The system consisted of the UAV, water sampling [...] Read more.

Water quality sampling and monitoring are fundamental to water environmental protection. The purpose of this study was to develop a water quality sampling and multi-parameter monitoring system mounted on a multi-rotor unmanned aerial vehicle (UAV). The system consisted of the UAV, water sampling and multi-parameter detection device, and path planning algorithm. The water sampling device was composed of a rotating drum, a direct current (DC) reduction motor, water suction hose, high-pressure isolation pump, sampling bottles, and microcontroller. The multi-parameter detection device consisted of sensors for potential of hydrogen (pH), turbidity, total dissolved solids (TDS), and a microcontroller. The flight path of the UAV was optimized using the proposed layered hybrid improved particle swarm optimization (LHIPSO) and rapidly-exploring random trees (RRT) obstacle avoidance path planning algorithm, in order to improve the sampling efficiency. Simulation experiments were conducted that compared the LHIPSO algorithm with the particle swarm optimization (PSO) algorithm and the dynamic adjustment (DAPSO) algorithm. The simulation results showed that the LHIPSO algorithm had improved global optimization capability and stability compared to the other algorithms, validating the effectiveness of the proposed algorithm. Field experiments were conducted at an aquaculture fish farm, and the device achieved real-time monitoring of three water quality parameters (pH, TDS, turbidity) at depths of 1 m and 2 m. A rapid analysis of three parameters (ammonia nitrogen, nitrite, dissolved oxygen) was performed in the laboratory on the collected water samples, and validated the feasibility of this study. Full article

(This article belongs to the Special Issue Application of AI and UAV Techniques in Urban Water Science)

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19 pages, 6765 KiB

Open AccessFeature PaperArticle

Ranking Sub-Watersheds for Flood Hazard Mapping: A Multi-Criteria Decision-Making Approach

by Nguyet-Minh Nguyen, Reza Bahramloo, Jalal Sadeghian, Mehdi Sepehri, Hadi Nazaripouya, Vuong Nguyen Dinh, Afshin Ghahramani, Ali Talebi, Ismail Elkhrachy, Chaitanya B. Pande and Sarita Gajbhiye Meshram

Water 2023, 15(11), 2128; https://doi.org/10.3390/w15112128 - 03 Jun 2023

Cited by 5 | Viewed by 1546

Abstract

The aim of this paper is to assess the extent to which the Sad-Kalan watershed in Iran participates in floods and rank the Sad-Kalan sub-watersheds in terms of flooding potential by utilizing multi-criteria decision-making approaches. We employed the entropy of a drainage network, [...] Read more.

The aim of this paper is to assess the extent to which the Sad-Kalan watershed in Iran participates in floods and rank the Sad-Kalan sub-watersheds in terms of flooding potential by utilizing multi-criteria decision-making approaches. We employed the entropy of a drainage network, stream power index (SPI), slope, topographic control index (TCI), and compactness coefficient (Cc) in this investigation. After forming a decision matrix with 25 possibilities (sub-watersheds) and 5 evaluation indices, we used four MCDM approaches, including the analytic hierarchy process (AHP), best–worst method (BWM), interval rough numbers AHP (IRNAHP), picture fuzzy with AHP (PF-AHP), and picture fuzzy with linear assignment model (PF-LAM, hereafter PICALAM) algorithms, to rank the sub-watersheds. The study results demonstrated that PICALAM exhibited superior performance compared to the other methods due to its consideration of both local and global weights for each criterion. Additionally, among the methods used (AHP, BWM, and IRNAHP) that showed similar performances in ranking the sub-watersheds, the BWM method proved to be more time-efficient in the ranking process. Full article

(This article belongs to the Special Issue Artificial Intelligence and Machine/Deep Learning for Hydro-Meteorological Forecasting)

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17 pages, 2773 KiB

Open AccessArticle

Competitive Adsorption of Drugs from a Multi-Component Mixture on Sugarcane Bagasse

by Maria E. Peñafiel and Damián Flores

Water 2023, 15(11), 2127; https://doi.org/10.3390/w15112127 - 03 Jun 2023

Cited by 2 | Viewed by 1619

Abstract

This work examines the adsorption in single- and multi-solute adsorption experiments of antibiotic and non-steroidal anti-inflammatory drugs, i.e., ciprofloxacin (CPX), sulfamethoxazole (SMX), ibuprofen (IBU), and diclofenac (DCF), onto sugarcane bagasse. The maximum experimental adsorption capacities of single components CPX, DCF, IBU, and SMX, [...] Read more.

This work examines the adsorption in single- and multi-solute adsorption experiments of antibiotic and non-steroidal anti-inflammatory drugs, i.e., ciprofloxacin (CPX), sulfamethoxazole (SMX), ibuprofen (IBU), and diclofenac (DCF), onto sugarcane bagasse. The maximum experimental adsorption capacities of single components CPX, DCF, IBU, and SMX, were 0.98, 0.77, 0.61, and 0.51 mg/g, respectively, with decreases between 5 and 28% in multi-solute mixtures, assuming competitive adsorption. The experimental data of a single drug fitted a pseudo-second-order model, while the experimental isotherms fit the Freundlich model. The presence of CPX did not interfere with the adsorption of other solutes. The adsorption of SMX was lower in the presence of adsorption competitors than SMX single solution. The adsorption of binary systems adequately fitted the Sheindorf–Rebhun–Sheintuch model. The results showed that the competition process depends on each adsorbate and that sugarcane bagasse can adsorb drugs in multi-component systems. Full article

(This article belongs to the Special Issue Adsorbents for Water and Wastewater Treatment and Resource Recovery - Volume II)

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17 pages, 5677 KiB

Open AccessArticle

Hydrogeochemical Characteristics and Environment Quality Assessment of Karst Groundwater in Mengzi Basin of Yunnan Province, China

by Xuchuan Duan, Zhiguo Sun, Shehong Li, Zhongcheng Jiang and Hongwei Liao

Water 2023, 15(11), 2126; https://doi.org/10.3390/w15112126 - 03 Jun 2023

Cited by 2 | Viewed by 1423

Abstract

One quarter of the world’s population uses karst groundwater. Due to the complex hydrological conditions in karst areas, they are vulnerable to pollution. The study of the hydrochemical characteristics and environmental quality evaluations of karst groundwater is of great significance for the rational [...] Read more.

One quarter of the world’s population uses karst groundwater. Due to the complex hydrological conditions in karst areas, they are vulnerable to pollution. The study of the hydrochemical characteristics and environmental quality evaluations of karst groundwater is of great significance for the rational development and utilization of karst groundwater. The study area is located in the Mengzi area of Yunnan Province, which is a typical karst area. The groundwater in the study area was analyzed and evaluated by a statistical analysis, hydrogeochemical analysis, ion ratio and Nemerow’s index method (P_N). The results show that the hydrochemical types are mainly the Ca–HCO₃ and Ca–Mg–HCO₃ types. The main hydrochemical compositions of groundwater were controlled by carbonate dissolution. The results of the water quality evaluation show that the main pollutants in the study area are Mn, COD and NO₃⁻. Compared with groundwater, the concentration and exceeding rate of pollutants in surface water are much higher than those in groundwater. There is the possibility of groundwater pollution by surface water infiltration. The results reveal the characteristics of groundwater pollution in typical karst areas and provide a theoretical basis for the rational development and utilization of groundwater. Full article

(This article belongs to the Topic Carbon-Energy-Water Nexus in Global Energy Transition)

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27 pages, 13984 KiB

Open AccessArticle

Influence of Long-Term Wind Variability on the Storm Activity in the Caspian Sea

by Elizaveta Kruglova and Stanislav Myslenkov

Water 2023, 15(11), 2125; https://doi.org/10.3390/w15112125 - 02 Jun 2023

Cited by 2 | Viewed by 1287

Abstract

Wind and wave conditions are limiting factors for economic activity, and it is very important to study the long-term variability of storm activity. The main motivation of this research is to assess the impact of wind variability on the storm activity in the [...] Read more.

Wind and wave conditions are limiting factors for economic activity, and it is very important to study the long-term variability of storm activity. The main motivation of this research is to assess the impact of wind variability on the storm activity in the Caspian Sea over the past 42 years. The paper presents the analysis of a number of storms based on the results of wave model WAVEWATCH III and the Peak Over Threshold method. The mean, maximum, and 95th percentile significant wave heights were analyzed by season. The highest waves were in the Middle Caspian Sea in winter. Detailed interannual and seasonal analyses of the number and duration of storm waves were performed for the whole Caspian Sea and its separate regions. Positive significant trends were found in the whole sea. Significant positive trends in the number and duration of storms were found for the North and Middle Caspian. In the South Caspian, the trends were negative and not significant. High correlations were found between the number of storms and events with wind speed > 10–14 m/s and 95th percentile wind speed. Positive trends in the number of storms in the Middle Caspian were caused by positive trends in extreme wind situations. Full article

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

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16 pages, 6212 KiB

Open AccessArticle

Laboratory Study of the Hydraulic Performance of the A-Type Triangular Piano Key Weir

by Forough Alizadeh Sanami, Amir Ghaderi, Fardin Alizadeh Sanami, Parisa Mirkhorli and Silvia Di Francesco

Water 2023, 15(11), 2124; https://doi.org/10.3390/w15112124 - 02 Jun 2023

Cited by 1 | Viewed by 1340

Abstract

A piano key weir (PKW), a new type of weir aiming to increase the discharge capacity of an existing dam, was recently designed. Despite a large body of research in this field, only a few studies were conducted on A-type triangular piano key [...] Read more.

A piano key weir (PKW), a new type of weir aiming to increase the discharge capacity of an existing dam, was recently designed. Despite a large body of research in this field, only a few studies were conducted on A-type triangular piano key weirs (TPKW) in straight channels. In this context, this present research sought to study the flow regime, stage–discharge relationship, and discharge coefficient. Experiments were carried out using nine TPKW models and three linear weirs (LW) as the control weirs. The results indicated that the triangular piano key weirs are capable of passing a higher discharge in similar laboratory conditions compared to linear key weirs due to their longer length. For a given h/P ratio (h is the water head over the weir crest, and P is the weir height) and constant length (L_e), an increase in the weir height from 0.07 m to 0.15 m decreases the discharge coefficient by approximately 20%. From sensitivity analysis, the most influential parameters for the tested TPKW models are the h/Le dimensionless ratio, followed by the P/L_e and Fr. Moreover, the discharge coefficient has a reverse trend when the dimensionless parameters h/P, h/L_e, and Froude number are increased. However, with decreasing h/L_e, the discharge coefficient of TPKW tends to that of a broad-crested weir because of local submergence. It is expected that the results obtained will be a reference for researchers who work in this field. Full article

(This article belongs to the Section Hydraulics and Hydrodynamics)

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18 pages, 11061 KiB

Open AccessArticle

Fish Diversity Monitoring Using Environmental DNA Techniques in the Clarion–Clipperton Zone of the Pacific Ocean

by Weiyi He, Lei Wang, Danyun Ou, Weiwen Li, Hao Huang, Rimei Ou, Jinli Qiu, Lei Cai, Lianghua Lin and Yanxu Zhang

Water 2023, 15(11), 2123; https://doi.org/10.3390/w15112123 - 02 Jun 2023

Viewed by 1579

Abstract

Marine fish populations have suffered the consequences of overfishing for a long time, leading to a loss in biodiversity. Traditional methods have been historically used to survey fish diversity but are limited to commercial species, particularly on the high seas. Environmental DNA (eDNA) [...] Read more.

Marine fish populations have suffered the consequences of overfishing for a long time, leading to a loss in biodiversity. Traditional methods have been historically used to survey fish diversity but are limited to commercial species, particularly on the high seas. Environmental DNA (eDNA) has been successfully used to monitor biodiversity in aquatic environments. In this study, we monitored fish diversity in the Clarion–Clipperton Zone (CCZ) of the Eastern Pacific Ocean using eDNA metabarcoding. Our results identified 2 classes, 35 orders, 64 families, and 87 genera. The genera Mugil, Scomberomorus, and Scomber had high relative abundance in the mesopelagic and demersal zone. Fish diversity varied with sampling sites, and the greatest number of species was found at a depth of 2500 m. Environmental changes drove fish aggregation, and our results indicated that Chla was negatively correlated with fish communities, while DO was positively correlated with fish communities. This study released the fish diversity pattern and the effects of the environment in the CCZ, which would provide useful information for biodiversity management and an environmental baseline for the International Seabed Authority. Full article

(This article belongs to the Special Issue Coastal Ecology and Fisheries Management)

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22 pages, 5424 KiB

Open AccessArticle

Modeling Multi-Objective Optimization with Updating Information on Humanitarian Response to Flood Disasters

by Xuehua Ji and Shaochuan Fu

Water 2023, 15(11), 2122; https://doi.org/10.3390/w15112122 - 02 Jun 2023

Viewed by 1100

Abstract

Unpredictable natural disasters brought by extreme climate change compound difficulties and cause a variety of systemic risks. It is thus critical to provide possibilistic scheduling schemes that simultaneously involve emergency evacuation and relief allocation. But the existing literature seldom takes emergency evacuation and [...] Read more.

Unpredictable natural disasters brought by extreme climate change compound difficulties and cause a variety of systemic risks. It is thus critical to provide possibilistic scheduling schemes that simultaneously involve emergency evacuation and relief allocation. But the existing literature seldom takes emergency evacuation and relief supplies as a joint consideration, nor do they explore the impact of an unpredictable flood disaster on the scheduling scheme. A multi-stage stochastic programming model with updating information is constructed in this study, which considers the uncertainty of supply and demand, road network, and multiple types of emergency reliefs and vehicles. In addition, a fuzzy algorithm based on the objective weighting of two-dimensional Euclidean distance is introduced, through moderating an effect analysis of the fuzzy number. Computational results show that humanitarian equity for allocating medical supplies in the fourth period under the medium and heavy flood is about 100%, which has the same as the value of daily and medical supplies within the first and third period in the heavy scenarios. Based on verifying the applicability and rationality of the model and method, the result also presents that the severity of the flood and the fairness of resources is not a simple cause-and-effect relationship, and the consideration of survivor is not the only factor for humanitarian rescue with multi-period. Specifically, paying more attention to a trade-off analysis between the survival probability, the timeliness, and the fairness of humanitarian service is essential. The work provides a reasonable scheme for updating information and responding to sudden natural disasters flexibly and efficiently. Full article

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26 pages, 4503 KiB

Open AccessArticle

Association of Flood Risk Patterns with Waterborne Bacterial Diseases in Malaysia

by Nur Zahidah Shafii, Ahmad Shakir Mohd Saudi, Jyh Chyang Pang, Izuddin Fahmy Abu, Norzahir Sapawe, Mohd Khairul Amri Kamarudin and Mohamad Haiqal Nizar Mohamad

Water 2023, 15(11), 2121; https://doi.org/10.3390/w15112121 - 02 Jun 2023

Cited by 1 | Viewed by 2123

Abstract

Flood risk has increased distressingly, and the incidence of waterborne diseases, such as diarrhoeal diseases from bacteria, has been reported to be high in flood-prone areas. This study aimed to evaluate the flood risk patterns and the plausible application of flow cytometry (FCM) [...] Read more.

Flood risk has increased distressingly, and the incidence of waterborne diseases, such as diarrhoeal diseases from bacteria, has been reported to be high in flood-prone areas. This study aimed to evaluate the flood risk patterns and the plausible application of flow cytometry (FCM) as a method of assessment to understand the relationship between flooding and waterborne diseases in Malaysia. Thirty years of secondary hydrological data were analysed using chemometrics to determine the flood risk patterns. Water samples collected at Kuantan River were analysed using FCM for bacterial detection and live/dead discrimination. The water level variable had the strongest factor loading (0.98) and was selected for the Flood Risk Index (FRI) model, which revealed that 29.23% of the plotted data were high-risk, and 70.77% were moderate-risk. The viability pattern of live bacterial cells was more prominent during the monsoon season compared to the non-monsoon season. The live bacterial population concentration was significantly higher in the midstream (p < 0.05) during the monsoon season (p < 0.01). The flood risk patterns were successfully established based on the water level control limit. The viability of waterborne bacteria associated with the monsoon season was precisely determined using FCM. Effective flood risk management is mandatory to prevent outbreaks of waterborne diseases. Full article

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19 pages, 2196 KiB

Open AccessArticle

Agricultural Practices for Hillslope Erosion Mitigation: A Case Study in Morocco

by Jean Marie Vianney Nsabiyumva, Ciro Apollonio, Giulio Castelli, Andrea Petroselli, Mohamed Sabir and Federico Preti

Water 2023, 15(11), 2120; https://doi.org/10.3390/w15112120 - 02 Jun 2023

Cited by 1 | Viewed by 1847

Abstract

In the last decades, the Rif area in Morocco has been frequently affected by soil erosion due to intense rainfall events. In order to help farmers improve their lives and avoid damages caused by this phenomenon, a management project (the MCA Project) aiming [...] Read more.

In the last decades, the Rif area in Morocco has been frequently affected by soil erosion due to intense rainfall events. In order to help farmers improve their lives and avoid damages caused by this phenomenon, a management project (the MCA Project) aiming to grow fruit trees has been realized. The objective of this study was to evaluate, in three provinces of Morocco, the effect on the hydrological response of selected erosion control management techniques combined with olive tree plantations. The investigated variables were the final infiltration (If), the imbibition of rainwater (Pi), the runoff coefficient (Kr), and the soil detachment (D). In particular, for each investigated soil utilization, three replications of a rain simulation test (80 mm/h) and soil sampling were conducted. Results for surface conditions demonstrate that under vegetation in matorral and fallow, the surface is covered at more than 75% with a high content of organic matter (OM) at 4.5% and 2.6%, respectively. Despite the compaction observed in those land uses, the surface area opened exceeded 90% in the study area. Regarding the soils physical properties, they were rich in silt at more than 40%; the rate of porosity is high where bulk density is low. At the Taounate site, low porosity was at 62% in fallow and at 55% in plowing, with high densities of 1.01 g/cm² and 1.2 g/cm², respectively. Tests also demonstrate that vegetation has an important role in moisture conservation in the depths of 0 to 10 cm at all sites with macroagregate stability (MA%) compared to plowing sites. In terms of soil hydrology, vegetation reduces the runoff because, under matorral (it was at 0%), it avoids soil erosion. Full article

(This article belongs to the Special Issue Soil Erosion Measurement Techniques and Field Experiments)

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21 pages, 11676 KiB

Open AccessArticle

Climate Change and Hydrological Response in the Ranwu Lake Basin of Southeastern Tibet Plateau

by Yingying Cui, Liping Zhu, Jianting Ju, Lun Luo and Yongjie Wang

Water 2023, 15(11), 2119; https://doi.org/10.3390/w15112119 - 02 Jun 2023

Viewed by 1181

Abstract

It is of great practical significance to accurately distinguish the different water supply sources of rivers and lakes under climate change for regional water resources utilization. This study examines the impact of climate change on the hydrological processes of the Ranwu Lake basin [...] Read more.

It is of great practical significance to accurately distinguish the different water supply sources of rivers and lakes under climate change for regional water resources utilization. This study examines the impact of climate change on the hydrological processes of the Ranwu Lake basin in the southeastern Tibet Plateau. The authors used China Meteorological Forcing Dataset (CMFD) historical data, CanESM5′s future climate predictor, and the SPHY model to analyze trends in temperature, precipitation, and water supply sources in the basin. The study found that warming in the basin was higher than that in the Tibet Plateau, with high-altitude areas and winter showing more significant warming. From 1998 to 2018, precipitation in the basin showed a trend of fluctuation and decline. The study also found that glacial meltwater accounted for the majority of total runoff in the basin (54.13%), while snow meltwater, rainfall, and baseflow accounted for about 22.98%, 11.84%, and 11.06%, respectively, on average in recent years. The total runoff in the Ranwu Lake Basin will continue to decrease due to the accelerating retreat of glaciers, with the hydrological process transforming from being dominated by glacier processes to rain–snow processes. The study also predicts that three-quarters of glaciers in the basin will vanish within the next forty years, and by 2100, only around 20% of glaciers will remain. Full article

(This article belongs to the Special Issue Lake Processes and Lake’s Climate Effects under Global Warming)

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18 pages, 766 KiB

Open AccessArticle

Evaluation of Water Saving and Economy Impact for Tax Reform Policy Using CGE Model with Integrated Multiple Types of Water

by Shihao Shan, Hongzhen Ni, Xichen Lin and Genfa Chen

Water 2023, 15(11), 2118; https://doi.org/10.3390/w15112118 - 02 Jun 2023

Cited by 2 | Viewed by 1304

Abstract

As one of the important policy measures to promote water conservation and efficient utilization, the evaluation of water resources tax reform policy regarding its water saving and economic impact (WSEI) is a fundamental prerequisite for policy implementation. In this study, multiple types of [...] Read more.

As one of the important policy measures to promote water conservation and efficient utilization, the evaluation of water resources tax reform policy regarding its water saving and economic impact (WSEI) is a fundamental prerequisite for policy implementation. In this study, multiple types of water production modules, including surface water, groundwater, and unconventional water, were integrated into a CGE model. Hebei Province, the first pilot area in China, was used as a case study. Through a “with–without” comparative analysis scenario, three water resources tax policy simulations were designed to address the three key issues, and the results showed that the implementation of water resources tax policy would have a certain negative impact on industry economic output in the short term, but it could effectively suppress the use of conventional water and promote the utilization of unconventional water, which is beneficial for long-term water resource conservation and sustainability. The imposition of higher differential tax rates on high water-consuming industries is more effective in further promoting the use of unconventional water and reducing the use of conventional water to achieve water conservation targets. Moreover, providing tax refunds as subsidies to water-using industries could alleviate the economic impact of water resources tax and promote water conservation. From the perspectives of water quantity, water use efficiency, and economic impact, the optimal policy scenario (S3) was selected, involving implementing differential water resources tax rates of 23% for high water-consuming industries and 18% for general water-consuming industries, coupled with tax refunds and subsidies for sectors. Based on this, corresponding recommendations in terms of differential tax rate setting, tax utilization, government regulation, and agricultural water resources tax collection were provided. These findings can offer a scientific reference for the formulation and implementation of water resources tax policies in other regions. Full article

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

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22 pages, 889 KiB

Open AccessArticle

Emergency Evacuation Behavior in Small Island Developing States: Hurricane Irma in Sint Maarten

by Neiler Medina, Arlex Sanchez and Zoran Vojinovic

Water 2023, 15(11), 2117; https://doi.org/10.3390/w15112117 - 02 Jun 2023

Viewed by 2780

Abstract

Disasters triggered by natural hazards are becoming more frequent and more intense, causing damage to infrastructure and causing loss of life. One way to reduce disaster risk is by evacuating the hazardous area. However, despite the amount of literature that exists on evacuation [...] Read more.

Disasters triggered by natural hazards are becoming more frequent and more intense, causing damage to infrastructure and causing loss of life. One way to reduce disaster risk is by evacuating the hazardous area. However, despite the amount of literature that exists on evacuation behavior, there is still a lack of agreement on which variables can be used as predictors for individuals (or households) to actually evacuate. This lack of agreement can be related to the many variables that can affect the evacuation decision, from demographics, geographic, the hazard itself, and also local or cultural differences that may influence evacuation. Hence, it is essential to analyze and understand these variables based on the specifics of a case study. This study aims to find the most significant variables to be used as predictors of evacuation on the island of Sint Maarten, using data collected after the disaster caused by Hurricane Irma in September 2017. The results suggest that the variables gender, homeownership, percentage of property damage, quality of information, number of storeys of the house, and the vulnerability index are the most significant variables influencing evacuation decisions on the island. We believe the results of this paper offer a clear view to risk managers on the island as to which variables are most important in order to increase evacuation rates on Sint Maarten and to plan more efficiently for future evacuations. In addition, the variables found in this study have the potential to be the base information to set up, validate, and calibrate evacuation models. Full article

(This article belongs to the Section Hydrology)

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14 pages, 1317 KiB

Open AccessArticle

Monitoring of Microbial Contamination of Groundwater in the Upper Choluteca River Basin, Honduras

by Keylin Mendoza, Bryan Ortiz, Luis Rivera, Tania Peña, Marcio Chirinos-Escobar, Lourdes Enríquez, Victoria Maldonado and Gustavo Fontecha

Water 2023, 15(11), 2116; https://doi.org/10.3390/w15112116 - 02 Jun 2023

Cited by 2 | Viewed by 1965

Abstract

Water can act as a vector for several microbes with significant pathogenic potential for both humans and animals. Waterborne infections are a critical public health concern as they cause more than 3.4 million deaths annually. Total and thermotolerant coliforms and intestinal enterococci have [...] Read more.

Water can act as a vector for several microbes with significant pathogenic potential for both humans and animals. Waterborne infections are a critical public health concern as they cause more than 3.4 million deaths annually. Total and thermotolerant coliforms and intestinal enterococci have traditionally been used to assess the quality and suitability of drinking water. The aim of this study was to evaluate the microbiological quality of groundwater from six sub-basins located in the upper Choluteca River basin in Honduras and to determine the E. coli phylogroups isolated in these samples. Our findings show high rates of fecal contamination, which suggests that the groundwater in the basin is unsafe for human consumption. Phylogroups B1 and D were the most frequent among 99 E. coli isolates, while C and F were the least frequent phylogroups. Measures must be taken to raise awareness about sanitation and good practices for the management of household waste as well as the waste generated by agro-industrial activity and livestock. Full article

(This article belongs to the Topic Aquatic Environment Research for Sustainable Development)

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15 pages, 1042 KiB

Open AccessReview

Can the Invasive Seaweed Caulerpa cylidracea Represent a New Trophic Resource in the Mediterranean Sea?

by Lucia Rizzo and Tomás Vega Fernández

Water 2023, 15(11), 2115; https://doi.org/10.3390/w15112115 - 02 Jun 2023

Cited by 3 | Viewed by 1916

Abstract

Non-indigenous species (NIS) represent one of the greatest threats to biodiversity and ecosystem functioning, altering invaded habitats, competing with native species, and eventually becoming pests. The Mediterranean Sea is a marine biodiversity hotspot, with its coasts being densely populated and its living resources [...] Read more.

Non-indigenous species (NIS) represent one of the greatest threats to biodiversity and ecosystem functioning, altering invaded habitats, competing with native species, and eventually becoming pests. The Mediterranean Sea is a marine biodiversity hotspot, with its coasts being densely populated and its living resources fished since ancient times. As a result of such a long history of exploitation, the whole basin is exposed to a wide array of human pressures, with their combined effects on marine ecosystems being amplified by ongoing climate change. Caulerpa cylindracea Sonder, 1845, is a non-indigenous invasive seaweed widely distributed in the coastal habitats of the Mediterranean Sea, which ultimately affects marine biodiversity and ecosystem functioning. Here, a systematic literature analysis on the consumption of the NIS Caulerpa cylindracea by Mediterranean native and NIS species is provided, focusing on the benefits and drawbacks for the native biota and human health. The present review aims to synthetise knowledge and provide tools to manage the occurrence of the invasive seaweed C. cylindracea in the Mediterranean Sea, encouraging an ecosystem-based approach to the management of the ecological, economic, and social effects of the successful expansion of this NIS. Full article

(This article belongs to the Special Issue Anthropogenic Pressures on Marine Ecosystems)

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14 pages, 1863 KiB

Open AccessArticle

New Insight into Magnetic Enhanced Methane Production from Oily Sludge via Mesophilic Anaerobic Degradation Processes

by Jieying Liu and Zhigao Bi

Water 2023, 15(11), 2114; https://doi.org/10.3390/w15112114 - 02 Jun 2023

Viewed by 1045

Abstract

Anaerobic digestion is a promising technology for treating and disposing of oily sludge, but the presence of oil in the sludge reduces methane production and sludge volume reduction. To overcome this limitation, this study creatively reports the use of magnetite to enhance methane [...] Read more.

Anaerobic digestion is a promising technology for treating and disposing of oily sludge, but the presence of oil in the sludge reduces methane production and sludge volume reduction. To overcome this limitation, this study creatively reports the use of magnetite to enhance methane production in oily sludge mesophilic anaerobic digestion and elucidates the underlying mechanism. Results show that the addition of magnetite increases methane production, with a 5% magnetite content leading to a 1.42-fold increase in cumulative methane output compared to the blank. Mechanistically, magnetite accelerates the release of organic matter, promotes oil degradation, increases volatile fatty acids (VFA) accumulation, and reduces the proportion of propionate. Additionally, magnetite alleviates pH decreases and increases the release of ammonia nitrogen and phosphate, resulting in effective sludge reduction, with volatile suspended solids (VSS) reduction ranging from 26.9% to 32.6%, higher than that of the blank. Moreover, magnetite accelerates electron transfer and increased the relative abundance of microorganisms associated with methane production, with the relative abundance of Methanosarcina increasing to 37.6~38.5% due to the presence of magnetite. This study provides a theoretical framework for effectively utilizing oily sludge through the application of magnetite. Full article

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12 pages, 12892 KiB

Open AccessArticle

Evaluating Surface Water Nitrogen Pollution via Visual Clustering in Megacity Chengdu

by Yao Ding, Yin Wang, Shuming Yang, Xiaolong Zhao, Lili Ouyang and Chengyue Lai

Water 2023, 15(11), 2113; https://doi.org/10.3390/w15112113 - 02 Jun 2023

Cited by 2 | Viewed by 1235

Abstract

The current standards used for nitrogen pollution evaluation are lacking, and scientific classification methods are needed for nitrogen pollution to improve water quality management capabilities. This study addresses the important issue of assessing surface water nitrogen pollution by utilizing two advanced multivariate statistical [...] Read more.

The current standards used for nitrogen pollution evaluation are lacking, and scientific classification methods are needed for nitrogen pollution to improve water quality management capabilities. This study addresses the important issue of assessing surface water nitrogen pollution by utilizing two advanced multivariate statistical techniques: self-organizing maps (SOMs) obtained using the K-means algorithm and the Hasse diagram technique (HDT). The research targets of this study are the rivers of the megacity Chengdu, China. Samples were collected on a monthly basis in 2017–2020 from different sites along the rivers, and their nitrogen pollution parameters were determined. The grouping of nitrogen pollution parameters and the clustering of sampling events using SOMs facilitate the preprocessing required for the HDT, wherein clusters are ordered according to the pre-clustered water sampling events. The results indicate that nitrogen pollution in the Chengdu River Basin, which is prominent and mainly driven by nitrate nitrogen, can be categorized into five levels. The nitrogen pollution in Tuo River is serious. Although the degree of ammonia nitrogen pollution in Jin River is higher, the pollution range is smaller. Furthermore, these results were evaluated by the SOMs and HDT to be clear and reliable. Overall, these findings can provide a basis for local environmental legislation. Full article

(This article belongs to the Special Issue Research on Nutrient Dynamics in Surface Water Using Water Quality Models and State-of-the-Art Monitoring)

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19 pages, 6799 KiB

Open AccessFeature PaperArticle

Assessment of Spatiotemporal Groundwater Recharge Distribution Using SWAT-MODFLOW Model and Transient Water Table Fluctuation Method

by Hiyaw Hatiya Ware, Tarekegn Dejen Mengistu, Bisrat Ayalew Yifru, Sun Woo Chang and Il-Moon Chung

Water 2023, 15(11), 2112; https://doi.org/10.3390/w15112112 - 02 Jun 2023

Cited by 4 | Viewed by 2185

Abstract

Recharge is a crucial section of water balance for both surface and subsurface models in water resource assessment. However, quantifying its spatiotemporal distribution at a regional scale poses a significant challenge. Empirical and numerical modeling are the most commonly used methods at the [...] Read more.

Recharge is a crucial section of water balance for both surface and subsurface models in water resource assessment. However, quantifying its spatiotemporal distribution at a regional scale poses a significant challenge. Empirical and numerical modeling are the most commonly used methods at the watershed scales. However, integrated models inherently contain a vast number of unknowns and uncertainties, which can limit their accuracy and reliability. In this work, we have proposed integrated SWAT-MODFLOW and Transient Water Table Fluctuation Method (TWTFM) to evaluate the spatiotemporal distribution of groundwater recharge in Anyang watershed, South Korea. Since TWTFM also uses SWAT model percolation output data, calibration was performed for individual models and a coupled model. The coupled model was calibrated using daily streamflow and hydraulic head. The SWAT-MODFLOW model performed well during the simulation of streamflow compared to the SWAT model. The study output showed that the study watershed had significant groundwater recharge variations during the simulated period. A significant amount of recharge happens in the wet season. It contributes a significant amount of the average annual precipitation of the region. The direct flow components (surface and lateral) showed significant contributions when the water balance components were evaluated in the region. TWTFM showed a glimpse to estimate recharge, which requires representative monitoring wells in the study region. Comprehensively, the SWAT-MODFLOW model estimated groundwater recharge with reasonable accuracy in the region. Full article

(This article belongs to the Special Issue Novel Applications of Surface Water–Groundwater Modeling)

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