Water

14 pages, 754 KiB

Open AccessArticle

Detailed Insight into Gillnet Catches: Fish Directivity and Micro Distribution

by Karlos Moraes, Allan T. Souza, Mojmír Vašek, Milan Říha and Jan Kubečka

Water 2024, 16(18), 2683; https://doi.org/10.3390/w16182683 (registering DOI) - 20 Sep 2024

Gillnets are widely used in research and commercial fishery activities. As passive gear, gillnets can be selective and dependent on the diel migration of fish. In areas with limited littoral extent, inshore–offshore migration may cause bias in the gillnet catch. Our hypothesis was [...] Read more.

Gillnets are widely used in research and commercial fishery activities. As passive gear, gillnets can be selective and dependent on the diel migration of fish. In areas with limited littoral extent, inshore–offshore migration may cause bias in the gillnet catch. Our hypothesis was that some factors, such as gillnet saturation, fish depletion, or chemical cues, could be the cause of the bias. We used a total of 66 CEN gillnets deployed at Římov Reservoir parallel to the shore at different positions of littoral-pelagic gradient. Individual fish direction was recorded from inshore, offshore, or unknown direction (i.e., entangled fish). A total of 5791 fishes from nine different species were caught. For most fish, it was possible to determine their directivity, and most fish were captured in littoral or first pelagic gillnets. Shallower and deeper benthic gillnets differed in their bleak (Alburnus alburnus) catch. No significant differences were found between fish directions. At the species level, only asp (Leuciscus aspius) and ruffe (Gymnocephalus cernua) showed differences between the captured directions in one case. The results support the assumption that gillnet capture is a random process that to a great extent is connected to random local movements. This is good news for fish monitoring projects. Sampling catch is likely to reflect true changes in the fish community, and not the effects of the deployment of the sampling gear. The experiment also showed that fish directivity statistics can be used for investigation of fish behavior and gear performance. Full article

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

18 pages, 1344 KiB

Open AccessArticle

Variations in Temperature and Pressure in the “Reservoir–Well” System Triggered by Blasting Recovery of Iron Ore at the Kursk Magnetic Anomaly

by Ella Gorbunova, Sofia Petukhova, Aleksey Ivanov, Zulfat Sharafiev, Dmitry Pavlov, Artem Karavaev and Andrey Fedorov

Water 2024, 16(18), 2682; https://doi.org/10.3390/w16182682 (registering DOI) - 20 Sep 2024

Abstract

This paper presents the results of precise measurements of temperature and pore pressure in the “reservoir–well” system during the development of iron ore deposits of the Kursk Magnetic Anomaly (KMA) via blasting. For the observation period from October 2021 to June 2024, variations [...] Read more.

This paper presents the results of precise measurements of temperature and pore pressure in the “reservoir–well” system during the development of iron ore deposits of the Kursk Magnetic Anomaly (KMA) via blasting. For the observation period from October 2021 to June 2024, variations in compressibility, permeability and temperature in the upper Albian-Cenomanian confined aquifer, which is used for district water supply, were determined. The general trend in a decrease in water temperature was traced (from 12 °C to 11.4 °C). It was accompanied by an increase in the hydrostatic head (from 3.7 m to 7.4 m). Water temperature in the upper aquifer was measured for 9 industrial explosions in the mine and for 30 explosions in the quarry. For one explosion in the mine and five explosions in the quarry the coseismic changes in water temperature with amplitudes of 0.06–0.09 °C were established, while changes in pore pressure in the “reservoir–well” system were 0.4–2.2 kPa. Local changes in the permeability of the reservoir in the vicinity of the well (the skin effect) are considered to be the main factor that controls the coseismic response of temperature during industrial explosions. As the reservoir permeability increases, the water temperature in the “reservoir–well” system can decrease and vice versa. The same pattern was observed according to regime measurements performed in 2022–2023. The recorded coseismic responses of water temperature in the upper aquifer in the high-frequency range are similar to the effects observed during propagation of seismic waves originated from earthquakes in the low-frequency range at different sites all over the world for the seismic energy density of 0.05–0.45 J/m³. The observed variations in aquifer temperature in the “reservoir–well” system under episodic dynamic impacts are of particular interest from the point of view of activating hydrogeochemical processes that accompany the development of iron ore deposits. Full article

(This article belongs to the Section Hydrogeology)

12 pages, 3442 KiB

Open AccessArticle

Assessment of Potentially Toxic Elements in Subtropical Urban Streams (Santo André, SP, Brazil)

by Rafaella M. T. Espeçoto, Marilena M. Luciano, Bruno L. Batista, Camila N. Lange, Heloísa F. Maltez, Luís C. Schiesari, Marcus V. França, Ângela T. Fushita, Lúcia H. G. Coelho and Ricardo H. Taniwaki

Water 2024, 16(18), 2681; https://doi.org/10.3390/w16182681 (registering DOI) - 20 Sep 2024

Abstract

Environmental contamination by potentially toxic elements (PTEs) poses a significant challenge, particularly in the metropolitan regions of developing countries. This issue arises from the high levels of pollution driven by industrial growth and the increased traffic from fossil fuel-powered vehicles. Even after the [...] Read more.

Environmental contamination by potentially toxic elements (PTEs) poses a significant challenge, particularly in the metropolitan regions of developing countries. This issue arises from the high levels of pollution driven by industrial growth and the increased traffic from fossil fuel-powered vehicles. Even after the wastewater treatment in treatment plants, PTEs often persist, posing risks to stream structure and function. This form of pollution is persistent, long-term, and irreversible, presenting a significant challenge in terms of freshwater conservation. This study aimed to assess the water quality and PTE concentrations in urban streams in Santo André, SP, Brazil, to identify the PTEs relevant to stream pollution. We analyzed the water quality in seven catchments in the Santo André municipality, in the metropolitan region of São Paulo, Brazil. The samples were collected during the dry (2021) and rainy periods (2022), and the concentrations of potentially toxic elements (PTEs) were analyzed via inductively coupled plasma–mass spectrometry (ICP-MS). The results showed elevated electrical conductivity (429 ± 211 μS·cm) and low dissolved oxygen concentrations in the streams (2.3 ± 0.95 μg·L), indicating potential problems such as eutrophication and toxicity to aquatic organisms. PTE concentrations, particularly those of Mn (30.8 ± 22.3 μg·L), Fe (91.1 ± 72.1 μg·L), and Zn (38.1 ± 28.7 μg·L), were among the highest concentrations. Seasonal variations affected the PTE concentrations, with Cr and Fe predominating during the dry season and Zn increasing during the rainy season. Associations were found between the PTE concentrations and the water pH, indicating the importance of continuous monitoring and remediation efforts. Full article

(This article belongs to the Special Issue Monitoring and Modelling of Contaminants in Water Environment)

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16 pages, 2917 KiB

Open AccessArticle

Image Recognition for Floating Waste Monitoring in a Traditional Surface Irrigation System

by Ana María Codes-Alcaraz, Herminia Puerto and Carmen Rocamora

Water 2024, 16(18), 2680; https://doi.org/10.3390/w16182680 (registering DOI) - 20 Sep 2024

Abstract

In the traditional surface irrigation system of Vega Baja del Segura (Spain), large amounts of floating waste accumulate at certain points of the river, irrigation channels and drainage ditches, causing malfunctioning of the irrigation network and rising social problems related to the origins [...] Read more.

In the traditional surface irrigation system of Vega Baja del Segura (Spain), large amounts of floating waste accumulate at certain points of the river, irrigation channels and drainage ditches, causing malfunctioning of the irrigation network and rising social problems related to the origins of waste. This work proposes a standardized and quick methodology to characterize the floating waste to detect changes in its amount and components. A dataset was created with 477 images of floating plastic items in different environments and was used for training an algorithm based on YOLOv5s. The mean Average Precision of the trained algorithm was 96.9%, and the detection speed was 81.7 ms. Overhead photographs were taken with an unmanned aerial vehicle at strategic points of the river and channels, and its automatic count of floating objects was compared with their manual count. Both methods showed good agreement, confirming that water bottles were the most abundant (95%) type of floating waste. The automatic count reduced the required time and eliminated human bias in image analysis of the floating waste. This procedure can be used to test the reach of corrective measures implemented by local authorities to prevent floating waste in the river. Full article

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20 pages, 11408 KiB

Open AccessArticle

Early Warning of Sudden Water Pollution Accident Risks Based on Water Quality Models in the Three Gorges Dam Area

by Na Zhao, Yonggui Wang, Jun Yang, Ruikai Chen, Xiaoyu Wang and Yinqun Yang

Water 2024, 16(18), 2679; https://doi.org/10.3390/w16182679 (registering DOI) - 20 Sep 2024

Abstract

In recent years, sudden water pollution accidents have frequently occurred and seriously endangered people’s drinking water safety. Early warnings for water pollution accidents has become the core work for emergency response and sparked substantial research. However, risk assessments for different water receptors still [...] Read more.

In recent years, sudden water pollution accidents have frequently occurred and seriously endangered people’s drinking water safety. Early warnings for water pollution accidents has become the core work for emergency response and sparked substantial research. However, risk assessments for different water receptors still needs to be solved for the early warning of water pollution accidents. This paper proposes a new early warning assessment method based on water quality models for different receptors, divided into the water source area (including drinking water source area and agricultural water use area) and the non-water source area. The constructed method was applied to the Three Gorges Dam area in China to simulate a phosphorus leakage accident caused by a traffic accident. Based on the EFDC model, the migration evolution process and the distribution change characteristics of phosphorus were simulated. Accordingly, the different risk levels of zones between the incident site and the downstream drinking water source area were obtained. The application results show that the risk warning system for sudden water pollution accidents based on the water quality model proposed in this paper can be applied to provide scientific support for the emergency response of sudden water pollution accidents. Full article

(This article belongs to the Special Issue Spatial–Temporal Variation and Risk Assessment of Water Quality)

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16 pages, 3827 KiB

Open AccessArticle

Effects of Deficit-Regulated Irrigation on Root-Growth Dynamics and Water-Use Efficiency of Winter Wheat in a Semi-Arid Area

by Ziqian Wang, Bo Zhang, Jiahao Li, Shihao Lian, Jinshan Zhang and Shubing Shi

Water 2024, 16(18), 2678; https://doi.org/10.3390/w16182678 (registering DOI) - 20 Sep 2024

Abstract

Water management is critical for wheat production under extreme drought conditions, and the mechanisms by which root dynamics and soil water utilization affect wheat yield are uncertain. This study was conducted in 2023–2024 under a mesophilic semi-arid climate with a two-factor partitioned experimental [...] Read more.

Water management is critical for wheat production under extreme drought conditions, and the mechanisms by which root dynamics and soil water utilization affect wheat yield are uncertain. This study was conducted in 2023–2024 under a mesophilic semi-arid climate with a two-factor partitioned experimental design, aiming to assess the response of different irrigation amounts in winter wheat crops on root growth and development, soil water utilization, and yields in different soil horizons. The results showed that variety and irrigation volume had significant effects on the spatial and temporal distribution of root and yield components, with irrigation volume having the greatest effect on yield. Compared with CK, deficit-regulated irrigation significantly promoted root penetration to deeper layers and delayed root senescence. DRWD, RLD, RSA, and RV decreased gradually with increasing soil depth, and the peaks of RLD, RSA, and RV appeared at the tassel to flowering stage, respectively; and under deficit-regulated irrigation, the contribution of the A2W4 treatment to stable yield was greater. Therefore, A2W4 is an effective water-saving irrigation method to improve grain yield and water-use efficiency under deficit-regulated irrigation. Full article

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

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16 pages, 10088 KiB

Open AccessArticle

Increased Sensitivity and Accelerated Response of Vegetation to Water Variability in China from 1982 to 2022

by Huan Tang, Jiawei Fang, Yang Li and Jing Yuan

Water 2024, 16(18), 2677; https://doi.org/10.3390/w16182677 (registering DOI) - 20 Sep 2024

Abstract

Understanding how plants adapt to shifting water availability is imperative for predicting ecosystem vulnerability to drought. However, the spatial–temporal dynamics of the plant–water relationship remain uncertain. In this study, we employed the latest Global Inventory Modeling and Mapping Studies (GIMMS) Normalized Difference Vegetation [...] Read more.

Understanding how plants adapt to shifting water availability is imperative for predicting ecosystem vulnerability to drought. However, the spatial–temporal dynamics of the plant–water relationship remain uncertain. In this study, we employed the latest Global Inventory Modeling and Mapping Studies (GIMMS) Normalized Difference Vegetation Index (NDVI4g), an updated version succeeding GIMMS NDVI3g spanning from 1982 to 2022. We integrated this dataset with the multiple scale Standardized Precipitation Evapotranspiration Index (SPEI 1 to 24) to investigate the spatial–temporal variability of sensitivity and lag in vegetation growth in response to water variability across China. Our findings indicate that over 83% of China’s vegetation demonstrates positive sensitivity to water availability, with approximately 66% exhibiting a shorter response lag (lag < 1 month). This relationship varies across aridity gradients and diverges among plant functional types. Over 66% of China’s vegetation displays increased sensitivity to water variability and 63% manifests a short response lag to water changes over the past 41 years. These outcomes significantly contribute to understanding vegetation dynamics in response to changing water conditions, implying a heightened susceptibility of vegetation to drought in a future warming world. Full article

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15 pages, 20333 KiB

Open AccessArticle

Comparative Analysis of Water Quality in Major Rivers of Türkiye Using Hydrochemical and Pollution Indices

by Veysel Süleyman Yavuz, Veysi Kartal and Mariacrocetta Sambito

Water 2024, 16(18), 2676; https://doi.org/10.3390/w16182676 - 20 Sep 2024

Abstract

This study provides a comprehensive analysis of the water quality in five major rivers in Türkiye: Sakarya, Yeşilırmak, Kızılırmak, Seyhan Rivers, and Niğde Creek. Utilizing hydrochemical diagrams and the River Pollution Index (RPI), we assess the temporal and spatial variations in water quality [...] Read more.

This study provides a comprehensive analysis of the water quality in five major rivers in Türkiye: Sakarya, Yeşilırmak, Kızılırmak, Seyhan Rivers, and Niğde Creek. Utilizing hydrochemical diagrams and the River Pollution Index (RPI), we assess the temporal and spatial variations in water quality over the past three decades. The hydrochemical characteristics reveal a dominant calcium-bicarbonate (Ca-HCO₃) type water, indicating strong geological control primarily influenced by carbonate weathering. Seasonal variations and anthropogenic influences, particularly agricultural runoff and industrial discharge, contribute to significant changes in ion concentrations, especially in the Kızılırmak and Yeşilırmak Rivers. The RPI results classify these rivers as ‘Severely polluted’ to ‘Moderately polluted’, driven by high levels of suspended solids and biochemical oxygen demand. This study underscores the urgent need for tailored pollution control measures and sustainable water management practices in order to mitigate the impacts of anthropogenic activities and protect the ecological health of these vital water resources. The findings provide a robust framework for future research and policymaking to enhance water quality monitoring and management strategies in the region. Full article

(This article belongs to the Special Issue Managing Water Resources Sustainably)

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14 pages, 4560 KiB

Open AccessArticle

The Quantification of the Ecosystem Services of Forming Ridges in No-Tillage Farming in the Purple Soil Region of China: A Meta-Analysis

by Lizhi Jia

Water 2024, 16(18), 2675; https://doi.org/10.3390/w16182675 - 20 Sep 2024

Abstract

Forming ridges in no-tillage farming (FRNF) is an important conservation tillage practice in the purple soil region of China. Whether FRNF will enhance ecosystem services remains unclear. There is a lack of a systematic quantitative research about the effect of FRNF on ecosystem [...] Read more.

Forming ridges in no-tillage farming (FRNF) is an important conservation tillage practice in the purple soil region of China. Whether FRNF will enhance ecosystem services remains unclear. There is a lack of a systematic quantitative research about the effect of FRNF on ecosystem services. We collected 611 data entries from 21 previous publications to quantitatively evaluate the effects of FRNF on runoff and sediment loss, soil physicochemical properties and biomass. The results showed that compared with conventional tillage, (1) FRNF reduced runoff and sediment loss by 49% and 73%, respectively, due to the blocking effect of the ridge-ditch structure; (2) FRNF increased the concentrations of soil organic carbon, total nitrogen, available nitrogen, available phosphorus and available potassium by 15%, 14%, 30%, 58% and 17%, respectively; (3) FRNF decreased soil bulk density on the ridges by 11% and increased soil moisture content in the furrows by 28%, while it had insignificant effects on soil bulk density in the furrows and soil moisture content on the ridges; and (4) FRNF increased aboveground and belowground biomass (maize, oilseed rape, potato, sweet potato and wheat) by 23% and 63%, respectively. Overall, these results highlighted the importance of FRNF in regulating soil erosion, physicochemical properties and biomasses in the purple soil region of China. The implementation of FRNF in this region could significantly improve the ecosystem services in agro-ecosystems. Full article

(This article belongs to the Special Issue Soil and Water Management: Practices to Mitigate Nutrient Losses in Agricultural Watersheds, 2nd Edition)

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20 pages, 3156 KiB

Open AccessArticle

The Role of Scenario-Building in Risk Assessment and Decision-Making on Urban Water Reuse

by Rita Ribeiro and Maria João Rosa

Water 2024, 16(18), 2674; https://doi.org/10.3390/w16182674 - 19 Sep 2024

Abstract

Urban resilience and water resilience are both increasingly relying on urban non-potable water reuse under the context of the Climate Emergency, but sound risk assessment is lacking. Compared to the state of art, the proposed framework for health risk assessment and management of [...] Read more.

Urban resilience and water resilience are both increasingly relying on urban non-potable water reuse under the context of the Climate Emergency, but sound risk assessment is lacking. Compared to the state of art, the proposed framework for health risk assessment and management of urban non-potable water reuse includes (i) an additional step for establishing the context and (ii) the risk identification step being extended to introduce a description of the activities from which the hazard exposure scenarios may be built. This novel scenario-building process allows for a clear and comprehensive risk description, assessment, and treatment. The model of risk management is structured around three primary components: the decision-makers, i.e., the municipal services and the population at risk (users and workers); data elements relevant for the risk management process (reclaimed water quality, hazards, hazardous events, sites where exposure can happen, exposure routes, and activities developed by the population at risk and their vulnerabilities); and the links between the decision-makers and these elements and between the elements themselves. Its application in a representative case study shows that the framework comprehensively guides decision-making and communication to relevant stakeholders. From this practical exercise, the main recommendations were derived for risk mitigation by the municipal risk manager and the park users. Full article

(This article belongs to the Special Issue Enhancing Planning in the Management Urban Water Systems to Increase Resilience)

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14 pages, 9624 KiB

Open AccessArticle

Comprehensive Study on the Electrical Characteristics and Full-Spectrum Tracing of Water Sources in Water-Rich Coal Mines

by Donglin Dong, Fangang Meng, Jialun Zhang, Enyu Zhang and Xindong Lin

Water 2024, 16(18), 2673; https://doi.org/10.3390/w16182673 - 19 Sep 2024

Abstract

This study addresses the complex hydrogeological conditions and frequent inrush water incidents in the Donghuantuo coal mine by proposing a novel spectral tracing technique aimed at rapidly and accurately identifying the sources of inrush water. Through the analysis of electrical data from the [...] Read more.

This study addresses the complex hydrogeological conditions and frequent inrush water incidents in the Donghuantuo coal mine by proposing a novel spectral tracing technique aimed at rapidly and accurately identifying the sources of inrush water. Through the analysis of electrical data from the Donghuantuo mine, the electrical characteristics of the mine floor were examined. Systematic sampling of water from the primary aquifers within the mining area was conducted, followed by detailed spectral measurements, resulting in the establishment of a spectral database for inrush water sources in the Donghuantuo mine. The chaotic sparrow search optimization algorithm (CSSOA) was employed to optimize the key parameters of the random forest (RF) model, leading to the development of the CSSOA-RF spectral tracing identification model. This model demonstrated outstanding classification performance in the test set, achieving an accuracy of 100%. This research offers a novel, more accurate, and reliable method for identifying the sources of inrush water, facilitating the rapid identification of sources in coal-bearing regions of North China and reducing disaster losses. Although the geological structure of the study area is relatively simple, the research achieved significant results in identifying both single and mixed water sources. However, further validation and optimization are needed for its applicability in more complex geological conditions. The findings of this study provide crucial technical support for safe mining operations and hold significant reference value for water hazard prevention in similar regions. Full article

(This article belongs to the Special Issue Innovative Technologies for Mine Water Treatment)

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15 pages, 8128 KiB

Open AccessArticle

The Occurrence of Microplastics Pollution in the Surface Water and Sediment of Lake Chenghai in Southwestern China

by Lizeng Duan, Liancong Luo, Longwu Zhang, Donglin Li, Huayu Li, Tianbao Xu, Jing Xu and Hucai Zhang

Water 2024, 16(18), 2672; https://doi.org/10.3390/w16182672 - 19 Sep 2024

Abstract

Microplastics (MPs) in freshwater environments, such as lakes, have become a significant issue in recent years. However, studies on the lakes of the Yunnan Plateau have been limited. To understand the pollution status and sources of MPs in Lake Chenghai (LCH), 36 sampling [...] Read more.

Microplastics (MPs) in freshwater environments, such as lakes, have become a significant issue in recent years. However, studies on the lakes of the Yunnan Plateau have been limited. To understand the pollution status and sources of MPs in Lake Chenghai (LCH), 36 sampling sites were selected for the surface water and sediment samples. Morphological identification, compositional analysis, abundance measurement, and spatial distribution mapping of the MPs were carried out. We also performed correlation analyses with hydrological parameters and physicochemical indexes of water and sediments. We aimed to uncover the spatial distribution patterns of the MPs in LCH, along with potential sources. Our findings revealed that all samples contained MPs and all of them were fibers. The abundance of MPs ranged from 90 to 770 n/m³ (329.44 rms) in the water and from 10 to 115 n/kg (43.19 rms) in the sediments, with particle sizes of 1-3 mm and less than 1 mm, respectively. Transparent MPs were prevalent, comprising 68% of the MPs found in the water and 63% in the sediments. The primary components of the MPs were polypropylene (PP), polyethylene terephthalate (PET), and man-made fibers (rayon). The spatial distribution showed an increasing concentration of MPs from south to north in the surface water, whereas the opposite trend was found in the sediments. Human activities, prevailing winds, and the river flowing into the lake influenced the spatial distribution pattern of the MPs. The abundance and assemblage characteristics of the MPs were directly correlated with the factors of nitrogen, phosphorus, and particle size in the water and sediments, but the correlation was not significant. The main source of MPs was the production and livelihoods of the neighboring residents, especially the use of fishing gears and nets. Since LCH shows significant pollution from MPs, there is an urgent need to control and manage the watershed in order to reduce the input of MPs in the future. Full article

(This article belongs to the Special Issue Plateau Lake Water Quality and Biodiversity: Impacts of Human Activity and Trans-regional Water Diversion)

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15 pages, 2543 KiB

Open AccessArticle

Biochar Weakens the Efficiency of Nitrification Inhibitors and Urease Inhibitors in Mitigating Greenhouse Gas Emissions from Soil Irrigated with Alternative Water Resources

by Zhen Tao, Yuan Liu, Siyi Li, Baogui Li, Xiangyang Fan, Chuncheng Liu, Chao Hu, Shuiqing Zhang and Zhongyang Li

Water 2024, 16(18), 2671; https://doi.org/10.3390/w16182671 - 19 Sep 2024

Abstract

While previous studies have suggested that biochar, nitrification inhibitors, and urease inhibitors may reduce soil greenhouse gas emissions, their effectiveness in soils irrigated with alternative water resources remains unclear. To compensate for this, reclaimed water and livestock wastewater were utilized as alternative water [...] Read more.

While previous studies have suggested that biochar, nitrification inhibitors, and urease inhibitors may reduce soil greenhouse gas emissions, their effectiveness in soils irrigated with alternative water resources remains unclear. To compensate for this, reclaimed water and livestock wastewater were utilized as alternative water resources alongside groundwater control. Nitrapyrin and N-(n-butyl) thiophosphoric triamide and biochar were applied to the soil either individually or in combination, and a no-substance treatment (NS) was included for comparison. The results revealed that reclaimed water and livestock wastewater irrigation exacerbated the global warming potential. Compared to the NS, all exogenous substance treatments suppressed nitrous oxide (N₂O) emissions while increasing carbon dioxide (CO₂) emissions, and affecting methane (CH₄) emissions varied across treatments irrespective of the water types. Interestingly, the additional biochar reduced the inhibitory effect of the inhibitors on the greenhouse effect. Using nitrification inhibitors reduced the global warming potential by 48.3% and 50.1% under reclaimed water and livestock wastewater irrigation, respectively. However, when nitrification inhibitors were applied in combination with biochar, the global warming potential was increased by 52.1–83.4% compared to nitrification inhibitors alone, and a similar trend was also observed in the scenario of urease inhibitors, with increases ranging from 8.8 to 35.1%. Therefore, the combined application of biochar and inhibitors should be approached cautiously, considering the potential for increased greenhouse gas emissions. Full article

(This article belongs to the Special Issue Safe Application of Reclaimed Water in Agriculture)

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14 pages, 3336 KiB

Open AccessArticle

Ichthyoplankton Assemblages from the Coasts of Hamsilos Nature Park, Sinop, Southern Black Sea: Biodiversity, Abundance, and Relationships with Environmental Variables

by Orçin Uygun and Funda Üstün

Water 2024, 16(18), 2670; https://doi.org/10.3390/w16182670 (registering DOI) - 19 Sep 2024

Abstract

This study was conducted using monthly data collected between July 2015 and June 2016 in the marine area of Hamsilos Nature Park, located in Sinop, Southern Black Sea. The primary objectives were to determine the diversity of ichthyoplankton assemblages, examine seasonal variations, assess [...] Read more.

This study was conducted using monthly data collected between July 2015 and June 2016 in the marine area of Hamsilos Nature Park, located in Sinop, Southern Black Sea. The primary objectives were to determine the diversity of ichthyoplankton assemblages, examine seasonal variations, assess spatial differences between the inner and outer parts of Hamsilos Bay, and highlight the ecological relationships of the predominant species with environmental factors. The comprehensive collection during the study resulted in a mean abundance of 2217 eggs.10 m² and 2743 larvae.10 m², with 28 species belonging to 21 families identified. Specifically, Engraulis encrasicolus is the most abundant in spring and summer, Gaidropsarus mediterraneus is the most abundant in autumn, and Sprattus sprattus is the most abundant in winter. A temporal analysis revealed the highest abundances in August, September, and July, with the lowest in April, May, and February. Significant seasonal differences in abundance and diversity were detected. No spatial differences were found between the inner and outer areas of Hamsilos Bay. Small pelagic species dominated the ichthyoplankton community, while demersal species, though diverse, were less abundant. According to the results of the DistLM analysis, the structure of the ichthyoplankton community is influenced by temperature and salinity. During the study, the water temperature ranged from 8.35 °C in February to 25.50 °C in August, and the salinity varied from 17.67 psu in September to 19.04 psu in May. Full article

(This article belongs to the Special Issue Implementation of Biodiversity and Ecosystem Services in Marine Ecosystem Management, 3rd Edition)

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16 pages, 2529 KiB

Open AccessArticle

Hydrological Data Projection Using Empirical Mode Decomposition: Applications in a Changing Climate

by Che-Wei Chang, Jung-Chen Lee and Wen-Cheng Huang

Water 2024, 16(18), 2669; https://doi.org/10.3390/w16182669 - 19 Sep 2024

Abstract

This paper demonstrates the effectiveness and superiority of Empirical Mode Decomposition (EMD) in projecting non-stationary hydrological data. The study focuses on daily Sea Surface Temperature (SST) sequences in the Niño 3.4 region and uses EMD to forecast the probability of El Niño events. [...] Read more.

This paper demonstrates the effectiveness and superiority of Empirical Mode Decomposition (EMD) in projecting non-stationary hydrological data. The study focuses on daily Sea Surface Temperature (SST) sequences in the Niño 3.4 region and uses EMD to forecast the probability of El Niño events. Applying the Mann–Kendall test at the 5% significance level reveals a significant increasing trend in SST changes in this region, particularly noticeable after 1980. This trend is associated with the occurrence of El Niño and La Niña events, which have a recurrence interval of approximately 8.4 years and persist for over a year. The modified Oceanic Niño Index (ONI) proposed in this study demonstrates high forecast accuracy, with 97.56% accuracy for El Niño and 89.80% for La Niña events. Additionally, the EMD of SST data results in 13 Intrinsic Mode Functions (IMFs) and a residual component. The oscillation period increases with each IMF level, with IMF7 exhibiting the largest amplitude, fluctuating between ±1 °C. The residual component shows a significant upward trend, with an average annual increase of 0.0107 °C. These findings reveal that the EMD-based data generation method overcomes the limitations of traditional hydrological models in managing non-stationary sequences, representing a notable advancement in data-driven hydrological time series modeling. Practically, the EMD-based 5-year moving process can generate daily sea temperature sequences for the coming year in this region, offering valuable insights for assessing El Niño probabilities and facilitating annual updates. Full article

(This article belongs to the Special Issue Watershed Hydrology and Management under Changing Climate)

20 pages, 4588 KiB

Open AccessArticle

Dynamic Responses in a Pipe Surrounded by Compacted Soil Suffering from Water Hammer with Fluid–Structure–Soil Interactions

by Qiang Guo, Minyao Xu, Guizhong Xu and Huiling Xu

Water 2024, 16(18), 2668; https://doi.org/10.3390/w16182668 - 19 Sep 2024

Abstract

The current literature analyzing the dynamic response of coupled pipelines neglects the crucial interplay between the pipelines themselves and these constraints. This overlooked interaction has substantial influence on the fluid–structure coupling response, particularly in scenarios involving continuous constraints. We focus on a piping [...] Read more.

The current literature analyzing the dynamic response of coupled pipelines neglects the crucial interplay between the pipelines themselves and these constraints. This overlooked interaction has substantial influence on the fluid–structure coupling response, particularly in scenarios involving continuous constraints. We focus on a piping system surrounded by compacted soil, which is regarded as unbounded homogeneous elastic soil that suffers from water hammer. This study established a one-dimensional model for water pipe-embedded compacted soil with fluid–structure–soil interaction. Taking fluid–structure–soil interaction into account, fluid–structure interactions (FSIs) include Poisson coupling, junction coupling emerging at the fluid–structure interface, and pipe–soil coupling (PSC) emerging at the pipe–soil interface. In this study, as soil is assumed to be a homogeneous, isotropic elastic material, the coupling responses are more complex than those of an exposed pipe, and the relevant mechanisms justify further exploration to obtain well-predicted results. To mathematically describe this system considering fluid–structure–soil interaction, the four-equation FSI model was modified to accommodate the piping system surrounded by unbounded homogeneous elastic soil, employing the finite volume method (FVM) as a means to tackle and solve the dynamic problems with FSI and PSC, which partitions the computational domain into a finite number of control volumes and discretizes governing equations within each volume. The results were validated by the experimental and numerical results. Then, dynamic FSI responses to water hammer were studied in a reservoir–pipe–reservoir physical system. The hydraulic pressure, pipe wall stress, and axial motion were discussed with respect to different parameters. With the PSC and FSI taken into account, fluid, soil, and pipe signals were obviously observed. The results revealed the structural and fluid modes. Dynamic responses have been proven to be difficult to understand and predict. Despite this, this study provides a tractable method to capture more accurate systematic characteristics of a water pipe embedded in soil. Full article

(This article belongs to the Special Issue Recent Advances in Hydraulic Machinery and Its Application in Marine Engineering)

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13 pages, 1477 KiB

Open AccessArticle

In Vitro Potential of Antioxidant Extracts from Gracilaria gracilis Cultivated in Integrated Multi-Trophic Aquaculture (IMTA) for Marine Biobased Sector

by Simona Manuguerra, Rosaria Arena, Eleonora Curcuraci, Giuseppe Renda, Maxime Rannou, Claire Hellio, Concetta Maria Messina and Andrea Santulli

Water 2024, 16(18), 2667; https://doi.org/10.3390/w16182667 - 19 Sep 2024

Abstract

This study aimed to evaluate the antioxidant activity of bioactive compounds extracted from Gracilaria gracilis cultivated in an integrated multi-trophic aquaculture (IMTA) system by different extraction solvents and to investigate the potential capacity of the extracts in cellular systems against environmental pollutants. The [...] Read more.

This study aimed to evaluate the antioxidant activity of bioactive compounds extracted from Gracilaria gracilis cultivated in an integrated multi-trophic aquaculture (IMTA) system by different extraction solvents and to investigate the potential capacity of the extracts in cellular systems against environmental pollutants. The global yields, total polyphenol contents, and antioxidant activity were assessed on G. gracilis by DPPH radical scavenging activity, comparing the antioxidant extraction efficiency of the different solvents (ethanol 80%, acetone 70%, N-hexane, and water). Ethanol extract, granted by the highest extractive yield and antioxidant capacity, was tested in vitro in the Sparus aurata fibroblast (SAF-1) cell line to evaluate its protective role against oxidative stress induced by the chemical flame retardant 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47). The results demonstrate that the cells pretreated with G. gracilis extract were protected against oxidative stress and had improved cell viability, cellular antioxidant defense system, and cell cycle control, as demonstrated by the gene expression on some biomarkers related to the cell cycle (p53) and oxidative stress (nrf2, sod, and cat). These results confirm that bioactive compounds obtained from seaweeds cultivated in IMTAs could contribute to producing high-value ingredients that are able to counteract environmental stressors, for the growth of the marine biobased industrial sector and the expansion of new value chains. Full article

(This article belongs to the Special Issue Aquatic Ecotoxicology: A Tool for Monitoring the Effects of Anthropogenic Chemical Contamination on Fisheries and Aquaculture)

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19 pages, 3666 KiB

Open AccessArticle

Optimization of Secondary Chlorination in Water Distribution Systems for Enhanced Disinfection and Reduced Chlorine Odor Using Deep Belief Network and NSGA-II

by Bo Dong, Shihu Shu and Dengxin Li

Water 2024, 16(18), 2666; https://doi.org/10.3390/w16182666 - 19 Sep 2024

Abstract

This research explores the strategic optimization of secondary chlorination in water distribution systems (WDSs), in order to enhance the efficiency of disinfection while mitigating odor and operational costs and promoting sustainability in water quality management. The methodology integrates EPANET simulations for water hydraulic [...] Read more.

This research explores the strategic optimization of secondary chlorination in water distribution systems (WDSs), in order to enhance the efficiency of disinfection while mitigating odor and operational costs and promoting sustainability in water quality management. The methodology integrates EPANET simulations for water hydraulic and quality modeling with a deep belief network (DBN) within the deep learning framework for accurate chloric odor prediction. Utilizing the non-dominated sorting genetic algorithm-II (NSGA-II), this methodology systematically balances the objectives of chloride dosage and chloramine formation. It combines a chloric odor intensity assessment, a multi-component kinetic model, and dual-objective optimization to conduct a comparative analysis of case studies on secondary chlorination strategies. The optimal configuration with five secondary chlorination stations reduced chloric odor intensity to 1.20 at a cost of USD 40,020.77 per year in Network A while, with eight stations, chloric odor intensity was reduced to 0.88 at a cost of USD 71,405.38 per year in Network B. The results demonstrate a balanced trade-off between odor intensity and operational cost on one hand and sustainability on the other hand, highlighting the importance of precise chlorine management to improve both the sensory and safety qualities of drinking water while ensuring the sustainable use and management of water resources. Full article

(This article belongs to the Section Urban Water Management)

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12 pages, 6807 KiB

Open AccessArticle

Green Synthesis of Iron-Based Nanoparticles Using Pomegranate Leaf Extracts: Characterization, Biomolecules and Indole Removal

by Huifang Sun, Yanjun Liu, Yifan Zhou, Zuliang Chen and Jianfeng Li

Water 2024, 16(18), 2665; https://doi.org/10.3390/w16182665 - 19 Sep 2024

Abstract

This study investigates the synthesis of iron-based nanoparticles (Fe NPs) using pomegranate leaf extracts and their application in removing indole, a persistent organic pollutant commonly found in wastewater. The physicochemical properties of the synthesized Fe NPs and the active biomolecules in the pomegranate [...] Read more.

This study investigates the synthesis of iron-based nanoparticles (Fe NPs) using pomegranate leaf extracts and their application in removing indole, a persistent organic pollutant commonly found in wastewater. The physicochemical properties of the synthesized Fe NPs and the active biomolecules in the pomegranate leaf extracts were comprehensively characterized. Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) analyses revealed that the Fe NPs exhibited quasi-spherical shapes, with sizes ranging from 75 to 105 nm. Energy-Dispersive X-ray Spectroscopy (EDS) confirmed a homogeneous distribution of elements, including C, O, Fe, and S, on the nanoparticle surfaces, with weight percentages of 43.59%, 42.95%, 12.58%, and 0.88%, respectively. Fourier-transform infrared spectroscopy (FTIR) identified key functional groups like −OH, −COOH, and −C=O, which are essential for the capping and stabilization of the nanoparticles. Biomolecules such as ellagic acid (C₁₄H₆O₈) and gallic acid (C₇H₆O₅) functioned as reducing agents, improving nanoparticle dispersion and preventing aggregation. The synthesized Fe NPs quickly achieved 45.5% removal of indole within just 20 min and maintained a stable removal efficiency of approximately 51.4% after 90 min. This performance was attributed to the synergetic interaction between the biomolecules and the nanoparticles, with the monolayer adsorption of indole molecules on the Fe NP surfaces likely setting an upper limit on the maximum achievable removal efficiency. It appears from this study that pomegranate leaf extracts can be effectively utilized to synthesize Fe NPs as a novel and eco-friendly approach, demonstrating promising potential for the rapid removal of indole from aqueous solutions. Full article

(This article belongs to the Topic Towards Energy-Positive and Carbon-Neutral Technology for Wastewater Treatment and Reclamation)

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