Sources Of Water Pollution Research Articles

Gemini surfactant-engineered di-Schiff bases: Tailoring hydrophobicity to enhance catalytic and biological activities

This study explores the enhancement of catalytic performance of silver nanoparticles (AgNPs) using a series of gemini surfactants based on di-azomethine with varying hydrophobic tail lengths: DSGO, DSGD, and DSGH. By fine-tuning the molecular structure of these surfactants, we aim to develop more effective catalysts for purifying polluted water sources. The high surface energy of AgNPs often results in their aggregation, reducing their catalytic efficacy. However, increasing the surfactant tail length from 8 (DSGO) to 16 (DSGH) carbon atoms improves the stability and dispersibility of AgNPs, as confirmed by DLS, TEM, and UV analyses. DSGH, with its longer carbon tail, facilitates AgNPs synthesis with superior stability and smaller particle size, indicated by a higher zeta potential of +55.6 mV and a reduced size of 15.1 nm. This is attributed to the increased surface activity and hydrophobicity of the surfactants. As the tail length increases from 8 to 16, the investigated surfactant’s tendency for micellization and adsorption rises. Notably, DSGH exhibits the lowest critical micelle concentration (CMC) of 406 μM and the highest adsorption Gibbs free energy (ΔG°ads) of −59.08 kJ·mol−1 at 20 °C, enabling strong adsorption onto AgNPs. By modulating surfactant hydrophobicity, we effectively regulated AgNP catalytic activity. The DSGH/AgNPs composite shows enhanced catalytic activity, efficiently converting p-nitrophenol (p-NP) and methylene blue (MB) into less toxic species with apparent rate constants (kapp) of 0.368 and 0.537 min−1, respectively. Additionally, the AgNP-incorporated gemini surfactants exhibit promising antimicrobial activity against tested bacteria and fungi. Remarkably, the DSGD/AgNPs hybrid system surpasses commonly used commercial antimicrobial agents in efficacy. This study underscores the potential of manipulating surfactant structure to control the catalytic and antimicrobial activity of AgNPs.

The Influence of Age Factor and Industrial Area on The Malignancy Rate of Bone Tumours

Bone tumour is a term for a group of tumours located in the bones. World Health Organization data in 2020 stated that the incidence rate of bone sarcoma in the Americas and Europe was 0.8 per 100,000 population. Industrial development, especially in areas with high population density, has environmental impacts such as air pollution and contamination of water sources. This has been associated with an increase in the prevalence of bone tumours in children. However, studies on this matter are still limited. This study aims to analyze the effect of industrial areas and age factors on the level of bone tumour malignancy. This study used observational analytics with a case-control design. Osteosarcoma as the case variable and GCT as the control variable. The sample used was 106, consisting of 53 osteosarcoma tumours and 53 GCT tumours. Age classification is divided into 0-18 years and 319 years. Industrial area classification is divided into <2.5 km and 32.5 km. Bivariate analysis using the chi square test. Has obtained approval from the Health Research Ethics Commission (KEPK) of RSUD dr. Moewardi with Number: 1.557/VI/HREC/2024. Results found no significant effect of age factor on the level of bone tumour malignancy (p-value=0.204). Meanwhile, an insignificant effect was also found between the proximity of residence to industrial areas on the level of bone tumour malignancy (p-value=0.121). This study shows that age factor and proximity of residence to industrial areas do not affect the level of bone tumour malignancy.

Cigarette butt littering as a potential source of water pollution and human health risk

Smoked cigarette butts (CBs) serve as reservoirs for harmful contaminants. The objective of the current study is to assess the CB littering in Aizawl city and estimate its potential contribution to water pollution in downstream surface water sources, along with the associated human health risks. The spatial-temporal distribution of CB littering density (CBD) across the city, spanning various land-use patterns, was analyzed through a visual-oriented littering survey. With an annual average CBD of 0.438 ± 0.669 CBs/m2, commercial areas were identified as the littering hotspots. Further, the water pollution potential index (WPPI) was formulated considering leached concentrations of different contaminants from CBs into the water and their standard permissible limits. WPPI was calculated as 5.22 × 10−02, which represented water pollution potential from a single CB/L of water. This corresponded to a cumulative WPPI of (59.97 ± 6.68) × 10−06 from CB littering to surface water pollution through municipal sewerage system. The health risk assessment associated with CB littering was analyzed through the potential chronic daily intake (CDI) of leached contaminants, non-cancer risk (NCR), and cancer risk (CR). Heavy metals (lifetime exposure of 1125.9 mg from 1 CB/L) were found to be the most significant contributor to the cumulative CR (3.847 × 10−06) and hazard index (HI) (1.785 × 10−02). Further, it was estimated that the potential CR associated with 242 CBs/L in water is equivalent to smoking 1 cigarette per day for a lifetime. The WPPI, CR, and HI suggested that littered CBs can significantly contribute to water pollution.

Water quality and pollution source apportionment responses to rainfall in steppe lake estuaries: A case study of Hulun Lake in northern China

Hulun Lake, the largest inland steppe lake in China, is encountering severe water quality degradation. Estuaries play important roles in material and energetic exchange between rivers and lakes. The water quality at the estuaries of Hulun Lake directly reflects the impact of both human activities and natural factors on the lake’s overall water quality, especially during rainfall events. From July 28, 2021, to August 4, 2021, water samples from 62 sites were collected in the three estuaries of Hulun Lake before and after a moderate rainfall event. 13 water parameters, including dissolved oxygen (DO), Turbidity (Tur), Total Nitrogen (TN), Total Phosphorus (TP), Total Organic Nitrogen (TON), and Total Organic Phosphorus (TOP) were measured. The spatio-temporal distribution of water quality in the estuaries was assessed based on water quality index (WQI). Besides, an improved approach integrating stepwise linear regression (SLR) and principal component analysis (PCA) was utilized to construct a WQImin model for an effective assessment of water quality in these estuaries. Furthermore, the absolute principal component scores-multiple linear regression (APCS-MLR) model was employed to identify and quantify the environmental drivers underlying the water quality in the estuaries. The results of WQI indicated that the water quality of the sites in the estuaries of Hulun Lake was “medium” or “poor”, both before and after the rainfall, with a general deterioration in water quality in response to the rainfall. The simplified WQImin model consisted of 5 crucial parameters (i.e., TN, TP, ammonium (NH4+-N), Tur, and permanganate index (CODMn)), and it performed well without parameter weights. Spatial differences in some water parameters among the estuaries were detected, which were attributed to the natural factors and human activities upstream. The principal environmental factors affecting the water quality in the estuaries consisted of hydrodynamic processes, internal phosphorus release, external phosphorus input, external nitrogen input, nitrification in the estuaries, and external organic input and internal organic release. Therefore, we propose basin management strategies such as limiting grazing pressure, adopting enclosed pasture, wetland restoration, optimizing water renewal cycle in Hulun Lake, and transboundary water quality management to tackle water contamination in Hulun Lake.

The evolution patterns and driving factors of urban domestic water pollution utilizing China’s two national pollution source surveys

Characteristics of domestic water pollution are of significant practical importance for implementing targeted urban wastewater treatment strategies. The pollutant source census in China serves as a fundamental undertaking in the study of pollution sources, providing crucial data for the analysis of pollution from domestic sources. This study employs pollution coefficients derived from China's two national pollution source surveys, integrating spatial autocorrelation and center-of-gravity shift analysis methods to investigate the national-scale spatial evolution characteristics of major urban domestic water pollutants, including BOD, TN, TP, and Oils. Furthermore, the impact of urbanization processes in population, economic, social, and spatial dimensions on urban domestic water pollution sources is explored using the multi-scale geographically weighted regression (MGWR) method. The results show that: (1) Urban domestic water pollution exhibits an east-high and west-low distribution pattern, with EHL being the primary region of pollution generation. Compared to 2007, the western region experienced a faster increase in BOD (30% increase), while the eastern region showed a sharper decline in TN (45% decrease) by 2017. (2) The results of spatial autocorrelation show that high-value clusters of urban domestic water pollution are located in the eastern China and around Chongqing, while low-value clusters are extensively distributed in the western region, indicating significant spatial heterogeneity in water pollution. (2) Based on center-of-gravity analysis, pollution displays a discernible migration trend from the northeast to the southwest, with the center located near the border of Henan and Hubei provinces, within the latitudinal and longitudinal range of 32°N–32.79°N and 113.09°E–113.85°E. The migration distances, ranked in descending order, are as follows: Oils (72.23 km) > BOD (65.59 km) > TN (63.9 km) > TP (22.73 km). (3) Significant differences are observed in the effects and spatial regions influenced by urbanization factors across different dimensions. Population and social urbanization exhibit pollution-increasing effects, whereas economic and spatial urbanization demonstrate pollution-reducing effects. These results will deepen our understanding of the spatial differentiation patterns of urban domestic source pollution, providing theoretical guidance for alleviating the pressure of urban pollution management. In addition, this article is an in-depth study of the first two pollution source surveys, which can lay a research foundation for future investigation work.

Effects of Agricultural Insurance on Water Pollution in China

Water pollution is the most serious environmental problems in China now, water pollution directly affects people's quality of life and the sustainable development of agriculture, and the biggest source of water pollution is agricultural non-point source pollution, so we need to pay more attention to the environmental impact of agricultural production and reduce agricultural non-point source pollution. This paper examines the environmental impact of agricultural insurance on water pollution. Using annual data from 30 provinces across China between 2011 and 2019, this paper employs a two-way fixed-effects model to examine the correlation between agricultural insurance development and agricultural pollutant emissions. Additionally, it takes agricultural carbon emissions and agricultural output value as dependent variables to comprehensively investigate the environmental and economic impacts of agricultural insurance. The research results indicate that the development of agricultural insurance has a significant effect on reducing agricultural water pollution and carbon emissions. The pollutant reduction effect is more significant in the major grain-producing areas. The positive environmental effect of agricultural insurance is based on the fact that the development of agricultural insurance is conducive to reducing the use of pesticides and chemical fertilisers and does not come at the expense of increased agricultural output.

Electrospinning of Sodium Alginate/Copper Oxide Nanofibrous Composite Membrane and Its Application of Cationic Dye Adsorption

AbstractDye wastewater is becoming one of the most significant sources of water pollution, and its impact on human survival is immeasurable. In this study, we successfully synthesized a nanofiber membrane with environmentally friendly and efficient properties using electrospinning of a mixture of sodium alginate (SA) and copper oxide (CuO) nanoparticles, aimed at effective dye removal. The adsorption performance of the SA/CuO nanofiber membrane was evaluated using the cationic dye methylene blue (MB). The maximum adsorption capacity of the nanofiber membrane was increased significantly with the addition of CuO nanoparticles, reaching a maximum value of 1633.4 mg g−1, almost twice as much as that of pure SA membrane. The adsorption kinetics follows the pseudo‐second‐order model, where chemisorption acts as the rate‐limiting step. The adsorption isotherm data indicate that the adsorption is monolayer. The nanofibrous membranes showed better dye removal under an alkaline environment. After four cycles of adsorption/desorption, the MB removal efficiency remained at 70.1% of the original adsorption capacity. The addition of CuO nanoparticles facilitated the adsorption of MB dyes, while the form of the nanofibrous membrane is easily recoverable and reusable. Therefore, the as‐prepared SA/CuO nanofibrous composite membrane is a potentially favorable adsorbent material for wastewater treatment applications.

Exploring the photocatalytic breakdown of organic pollutants using intercalated ZnO/SiO2 nanocomposites

The increasing prevalence of organic pollutants in water sources necessitates the development of efficient and cost-effective photocatalysts for their degradation. ZnO nanoparticles (NPs) have been widely studied for their photocatalytic properties; however, their application is hindered by low photocatalytic efficiency and high recombination rates of photogenerated carriers. This manuscript explores the enhanced photocatalytic performance of intercalated ZnO/SiO2 nanocomposites (NCs), synthesized through a combination of co-precipitation and Stöber methods, as a solution to these challenges. A comprehensive analysis of the structural, optical elemental and Morphological properties of both ZnO NPs and ZnO/SiO2 NCs was conducted using various characterization techniques, including X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), UV–Vis spectrometry and Brunauer-Emmett-Teller (BET) analysis. Through, XRD analysis, the calculated crystallite sizes of ZnO NPs and ZnO/SiO₂ NCs were found to be 36 nm and 39 nm respectively. TEM images illustrated that the ZnO NPs and ZnO/SiO₂ NCs have crystallized in elongated spherical morphology. XPS and FTIR analyses provided the signature band details the presence of Cu and Si in their Zn2⁺ and Si⁴⁺ oxidation states. The optical bandgap energies were calculated to be 3.38 eV for ZnO NPs and 3.22 eV for ZnO/SiO₂ NCs. The enhanced photocatalytic efficiency of the ZnO/SiO2 NCs achieved an impressive degradation rate of 92 % for Rhodamine B (RhB), compared to a relatively lower rate of 81 % for pure ZnO NPs for the degradation of RhB under visible light due to its lower bandgap, high surface area, and lower electron-hole recombination rate. BET surface area measurements revealed that ZnO nanoparticles have a surface area of 11.234 m2/g, while ZnO/SiO₂ NCs show 57.118 m2/g, highlighting SiO₂'s enhancement. The NCs demonstrated exceptional reusability for degradation, sustaining high efficiency across multiple cycles. Its ability to scavenge superoxide radicals highlighted the effectiveness of the ZnO/SiO₂ NCs in environmental remediation, especially for wastewater treatment.

Electro-coagulation technique using iron [Fe] and aluminium [Al] for microplastics removal from fashion industry wastewater, Thailand

The textile sector is considered as the 3rd largest source of water pollution and land degradation during 2020. of the world’s water pollution is linked with textile production and utilisation. Textile washing releases 14 million tons of microplastics, according to European Environmental Agency estimates. Wastewater Treatment Plant [WWTP] has declared everyday normal releases of more than 4 million MP particles because of its tiny size (<5mm) and low thickness (<1.2 g/cm3). Electrochemistry for the removal of tinny pollutants is recognised as an efficient treatment mechanism. The main aim of this research paper is to identify the efficiency of electro-coagulation technology using Fe and Al as anode and cathode in microplastic removal from Thailand’s textile industries. Results show the maximum 100% microplastic removal efficiency with pH 10 at a current density of 30 A/m2 within 60 minutes of the current supply. This paper helps to understand the role of electro-coagulation in Thailand textile wastewater plants and adopt the best available technique for microplastic removal.

Application of time series and multivariate statistical models for water quality assessment and pollution source apportionment in an Urban River, New Jersey, USA

Water quality monitoring reveals changing trends in the environmental condition of aquatic systems, elucidates the prevailing factors impacting a water body, and facilitates science-backed policymaking. A 2020 hiatus in water quality data tracking in the Lower Passaic River (LPR), New Jersey, has created a 5-year information gap. To gain insight into the LPR water quality status during this lag period and ahead, water quality indices computed with 16-year historical data available for 12 physical, chemical, nutrient, and microbiological parameters were used to predict water quality between 2020 and 2025 using seasonal autoregressive moving average (ARIMA) models. Average water quality ranged from good to very poor (34 ≤ µWQI ≤ 95), with noticeable spatial and seasonal variations detected in the historical and predicted data. Pollution source tracking with the positive matrix factorization (PMF) model yielded significant R2 values (0.9 < R2 ≤ 1) for the input parameters and revealed four major LPR pollution factors, i.e., combined sewer systems, surface runoff, tide-influenced sediment resuspension, and industrial wastewater with pollution contribution rates of 23–30.2% in the upstream and downstream study areas. Significant correlation of toxic metals, nutrients, and sewage indicators suggest similarities in their sources.Graphical

Sustainable Acid Mine Drainage Water Reclamation Using Silica-pectin Multichannel Tubular Membrane: A Comparison of Ultrafiltration Vs Pervaporation

The practice of coal mining has been demonstrated to exert a detrimental impact on the surrounding environment, particularly through the formation of acid mine drainage (AMD) ponds, which have the potential to pollute water sources. The reclamation of AMD is necessary to treat wastewater to ensure its safety for discharge into the environment and subsequent use as clean water. This study aims to treat AMD by comparing ultrafiltration (UF) and pervaporation (PV) processes utilizing silica-pectin multichannel membranes. The membranes were fabricated by coating silica-pectin sol on an inner surface of multichannel tubular support. The UF process was conducted under various pressures (1-3 bar), while the PV process was tested at various feed temperatures. Both permeate were collected and analyzed using several parameters (pH, Mn, and conductivity). The results showed that the UF process is more effective in collecting permeate flux over 136.6 L.h-1.m-2 at 3 bar pressure. Meanwhile, PV performs high permeate quality with Mn and conductivity rejection of 99.9 and 96.5%, respectively. Both UF and PV processes exhibit slightly increasing permeate pH with a range of 4.5-5.6. It concluded that multichannel silica-pectin membranes successfully reclamation AMD to enhance water quality. In addition, the UF process is more affordable for recycling AMD with high permeate flux, pretty good Mn, and conductivity rejection of over 95%.

An Assessment of Water Quality and Pollution Sources in a Source Region of Northwest China

China prioritizes ensuring drinking water safety, particularly in the water-scarce northwest region. This study, utilizing water quality data from 52 village and town water sources since August 2022, assesses water quality, with a specific focus on key indicators related to organic pollution sources. This study provides a scientific foundation for enhancing water quality in these sources. Employing category factor analysis for classification and grading, principal component analysis for qualitative analysis of key evaluation indicators, and the absolute principal component linear regression equation for quantitative calculation of pollution sources, this study reveals that all 52 water sources meet quality standards. Principal component analysis categorizes pollution sources as diverse types of organic compounds in surface water. Source analysis calculations highlight decay-type organic substances as major contributors to increased water color and permanganate index, with pollution contribution rates of 54.78% and 31.31%, respectively. Fecal-type organic substances dominate the increase in dissolved total solids and total coliforms, with pollution contribution rates of 56.65% and 40.16%, respectively. Additionally, high-molecular-weight organic substances exhibit lower concentrations in the water. This article presents a systematic water quality assessment methodology, which is used for the first time to qualitatively assess the types of water sources and to quantitatively trace specific sources of organic pollution in source water in northwest China. This systematic study’s results, involving initial assessment followed by traceability, recommend the adoption of a simple contact filtration and disinfection process to enhance water quality in the region.

Review of Waste Management in Indonesian Small Islands in the Last Five Years (2018-2023)

Indonesia is a maritime country composed of 16,771 islands consisting of large islands and small islands. One of the environmental problems that occur in small islands. Waste management is a shared focus because sources of water, soil and air pollution can come from waste. Waste management on small islands is very important because small islands have a much higher vulnerability than large islands.. This article aims to identify and analyze waste management in Indonesia's Small Islands and evaluate if its implementation has utilized the technology and concepts of the Industrial Revolution 4.0. Based on the findings of a review of 14 articles published from 2018-2023, with 15 islands as research objects, it was found that most of the small islands used as research objects had not managed their waste properly. The waste is eventually dumped into the sea. The unmanaged factor of this waste can be caused by the geographical conditions on the island which are bordered by the sea, the lack of waste management facilities, the limited land area on small islands and the low awareness and participation of the community in waste management. The rest, several islands have carried out the process of storage, processing, collection and destruction quite well. The waste is turned into handicrafts (bags and souvenirs), ecobricks, garden decorations and plant fertilizers for organic waste as well as the development of innovative waste into diesel fuel. Unfortunately, the intended application based on the Industrial Revolution 4.0 has not been reflected in waste management on these small islands. This is expected to be information and input for the government and managers as a model for other small islands in an effort to manage waste generation on the island's mainland and garbage contamination in the sea.

СУ ҚАУІПСІЗДІГІ: ФОРСАЙТ-ЗЕРТТЕУЛЕР ПРИЗМАСЫ АРҚЫЛЫ НЕГІЗГІ АСПЕКТІЛЕР МЕН ПЕРСПЕКТИВАЛАР

In the modern world, water security issues are becoming increasingly relevant and are key to ensuring the sustainable development of society. The world community faces serious challenges related to the threats of pollution of water sources, climate change, ecosystem instability and inefficient management of water resources. Solving these problems requires not only immediate measures, but also long-term strategies that can ensure the preservation of water security for the future. The research work is an analytical review of current problems in the field of water security and possible strategic solutions to solve them using foresight research methods. The article highlights the current threats and challenges facing water resources in the modern world, and discusses the advantages and effectiveness of applying foresight research methods in this area. Within the framework of the conducted scientific research, the key areas of strategic planning for ensuring water security in the future are highlighted through the highlighted through the analysis of the current state and forecasting potential changes in the water sector.

Visible light-induced periodate activation by Bi2WO6@nitrogen-deficient C3N4 composites for efficient degradation of tetracycline hydrochloride

Photocatalysis technology has been considered a green and efficient method to control tetracycline hydrochloride (TCH) pollution in potable water sources. In this paper, Bi2WO6-loaded photocatalysts on nitrogen-defective C3N4 (BWO@ND-C3N4) were constructed to synergistically promote the degradation of TCH under visible light by activating periodate (PI). TCH (20 mg/L) could be 100 % photo-degraded by BWO@ND-C3N4 (0.25 g/L) within 30 min when PI concentration is 1 mM. The BWO@ND-C3N4/activated PI system can also complete total TCH degradation when applied to actual water bodies and sunlight particularly (40 min for sunny days and 60 min for cloudy days). Besides, the system displayed good recycling stability under visible light, maintaining 90 % TCH degradation efficiency after 6 cycles. The degradation mechanism research showed that ·IO3, h+, ·OH, ·O2– and 1O2 are the main active substances in the degradation process. The superior TCH degradation performances of BWO@ND-C3N4 can be ascribed to the interfacial C-O bonds and the stable built-in electric field between BWO and ND-C3N4 for the fast separation of photogenerated carriers and activating PI, which can facilitate the rapid electron transfer, enhancing the TCH degradation kinetics. This work provides a broad application prospect of photocatalyst/activated PI systems for antibiotic pollution treatment in water.

A Sustainable Solution for the Adsorption of C.I. Direct Black 80, an Azoic Textile Dye with Plant Stems: Zygophyllum gaetulum in an Aqueous Solution.

The presence of pollutants in water sources, particularly dyes coming by way of the textile industry, represents a major challenge with far-reaching environmental consequences, including increased scarcity. This phenomenon endangers the health of living organisms and the natural system. Numerous biosorbents have been utilized for the removal of dyes from the textile industry. The aim of this study was to optimize discarded Zygophyllum gaetulum stems as constituting an untreated natural biosorbent for the efficient removal of C.I. Direct Black 80, an azo textile dye, from an aqueous solution, thus offering an ecological and low-cost alternative while recovering the waste for reuse. The biosorbent was subjected to a series of characterization analyses: scanning electron microscopy (SEM), thermogravimetric analysis (TGA), Brunauer-Emmett-Teller (BET) method, X-ray diffraction (XRD), and infrared spectroscopy (IR) were employed to characterize the biosorbent. Additionally, the moisture and ash content of the plant stem were also examined. The absorption phenomenon was studied for several different parameters including the effect of the absorption time (0 to 360 min), the sorbent mass (3 to 40 g/L), the pH of the solution (3 to 11), the dye concentration (5 to 300 mg/L), and the pH of the zero-charge point (2-12). Thermodynamic studies and desorption studies were also carried out. The results showed that an increase in plant mass from 3 to 40 g/L resulted in a notable enhancement in dye adsorption rates, with an observed rise from 63.96% to 97.08%. The pH at the zero-charge point (pHpzc) was determined to be 7.12. The percentage of dye removal was found to be highest for pH values ≤ 7, with a subsequent decline in removal efficiency as the pH increased. Following an initial increase in the amount of adsorbed dye, equilibrium was reached within 2 h of contact. The kinetic parameters of adsorption were investigated using the pseudo-first-order, pseudo-second-order and Elovich models. The results indicated that the pseudo-first-order kinetic model was the most appropriate for the plant adsorbent. The isotherm parameters were determined using the Langmuir, Frendlich, Temkin, and Dubinin-Radushkevich models. The experimental data were more satisfactory and better fitted using the Langmuir model for the adsorption of dye on the plant. This study demonstrated that Zygophyllum gaetulum stems could be employed as an effective adsorbent for the removal of our organic dye from an aqueous solution.

A novel framework reveals anthropogenic stressors of phosphorus polluted river-lake connection water system in Poyang lake basin of China

Poyang lake (PYL), as China's largest freshwater lake, has been suffering from increasing total phosphorus (TP) pollution associated with rapid basinal socio-economic development. However, anthropogenic phosphorus stressors were rarely examined in PYL basin due to its large-scale and complex river-lake connection water system, hampering phosphorus pollution control efforts. In this study, water pollution stress from multiple anthropogenic activities is quantitatively examined in PYL basin based on a newly developed framework coupling grey water footprint (GWF) analysis with the SPARROW model. Results show that the phosphorus source-sink process in PYL basin has been well simulated by SPARROW model quantifying an overall TP delivery rate of 0.39, with catchments closer to PYL showing higher delivery rate of phosphorus (up to over 0.8). The GWF analysis demonstrates that anthropogenic phosphorus sources have imposed much higher pollution stress on PYL than its inflowing rivers, with twelve catchments nearby PYL identified as critical source areas of TP contamination. Agricultural farming, livestock & poultry production, and urban household are recognized as the dominant anthropogenic stressors burdening water environment of PYL. Based on these, policy recommendations are provided for advancing control of the phosphorus pollution stressors. The methodology is effective in refined examination of water pollution sources, which is expected to be applied in other watersheds providing informative diagnosis of water issues especially in lakes.

Sustainable and Reusable Modified Membrane Based on Green Gold Nanoparticles for Efficient Methylene Blue Water Decontamination by a Photocatalytic Process.

Methylene blue (MB) is a dye hazardous pollutant widely used in several industrial processes that represents a relevant source of water pollution. Thus, the research of new systems to avoid their environmental dispersion represents an important goal. In this work, an efficient and sustainable nanocomposite material based on green gold nanoparticles for MB water remediation was developed. Starting from the reducing and stabilizing properties of some compounds naturally present in Lambrusco winery waste (grape marc) extracts, green gold nanoparticles (GM-AuNPs) were synthesized and deposited on a supporting membrane to create an easy and stable system for water MB decontamination. GM-AuNPs, with a specific plasmonic band at 535 nm, and the modified membrane were first characterized by UV-vis spectroscopy, X-ray diffraction (XRD), and electron microscopy. Transmission electron microscopy analysis revealed the presence of two breeds of crystalline shapes, triangular platelets and round-shaped penta-twinned nanoparticles, respectively. The crystalline nature of GM-AuNPs was also confirmed from XRD analysis. The photocatalytic performance of the modified membrane was evaluated under natural sunlight radiation, obtaining a complete disappearance of MB (100%) in 116 min. The photocatalytic process was described from a pseudo-first-order kinetic with a rate constant (k) equal to 0.044 ± 0.010 min-1. The modified membrane demonstrated high stability since it was reused up to 20 cycles, without any treatment for 3 months, maintaining the same performance. The GM-AuNPs-based membrane was also tested with other water pollutants (methyl orange, 4-nitrophenol, and rhodamine B), revealing a high selectivity towards MB. Finally, the photocatalytic performance of GM-AuNPs-based membrane was also evaluated in real samples by using tap and pond water spiked with MB, obtaining a removal % of 99.6 ± 1.2% and 98.8 ± 1.9%, respectively.

Evaluation of Groundwater Resources in the Middle and Lower Reaches of Songhua River Based on SWAT Model

The SWAT model primarily investigates sources of water pollution and conducts ecological assessments of surface water in contemporary hydrology and water resources research. To date, there have been limited accomplishments in the study of groundwater resources in China. The MODFLOW model currently primarily simulates groundwater levels and the migration of water quality, depending on the hydrological surface water data in the relevant area. This study aims to investigate the groundwater distribution characteristics of the middle and lower reaches of the Songhua River, a significant agricultural and grain production region in China. The research focuses on the middle and lower reaches of the Songhua River basin in Northeast China and employed the SWAT distributed hydrological model to simulate runoff. The monthly recorded runoff at Tongjiang Station in Jiamusi City was utilized to calibrate the model parameters. Consequently, the MODFLOW model was introduced to compare and assess the simulation outcomes of the SWAT model, ultimately ascertaining the distribution characteristics of shallow groundwater, groundwater recharge, recoverable volume, and groundwater levels in the Songhua River Basin. The findings indicate that: (1) The SWAT model demonstrates efficacy in the study region, achieving R2 and NS values of 0.81 and 0.76, respectively, thereby fulfilling the fundamental criteria for scientific research. The MODFLOW model exhibits strong performance in the study region, achieving a periodic R2 of 0.98 and a verification R2 of 0.97, with the discrepancy between simulated and actual groundwater levels confined to 0.6 m, thereby satisfying the criteria for scientific research. (2) In 2011, 2014, and 2016, the groundwater recharge in the middle and lower sections of the Songhua River was 24.33 × 108 m3, 30.79 × 108 m3, and 32.25 × 108 m3, respectively, aligning closely with the SWAT simulation results, while the average annual groundwater level depth was 8.17 m. (3) In the research area, groundwater recharging occurs primarily by atmospheric precipitation, while drainage predominantly transpires via groundwater as base flow, constituting 81.46%. Secondly, the recharge of shallow groundwater to deep aquifers is around 7.14%, with a minimal share attributed to vadose zone loss, constituting merely 2.1%. (4) From 2010 to 2016, the average groundwater runoff modulus of the middle and lower reaches of the Songhua River basin was 1.005 L/(s·km²), with a total recharge of 216.58 × 108 m3 and a total recoverable amount of 105.11 × 108 m3. The mean yearly supply was 25.11 × 108 m3. The total groundwater recharge was 26.54 × 108 m3 in the driest year (2011) and 33.25 × 108 m3 in the year of most ample water (2016).

Degradation of Nile Blue by Photocatalytic, Ultrasonic, Fenton, and Fenton-like Oxidation Processes

The aim of this study is to investigate new catalytic systems for the degradation of a dye that has been classified as first-degree toxic pollutant. Advanced oxidation process such as photocatalytic oxidation, ultrasonic oxidation, Fenton, and Fenton-like constitute a promising technology for the treatment of wastewater containing organic compounds. Waste effluents from textile industries are a major source of water pollution. These wastewaters contain dyes, which have high toxicity and low biodegradability. In this study, degradation of Nile Blue (NB), an azo dye, was studied using the photocatalytic oxidation (TiO2 and silver-loaded TiO2 (Ag-TiO2) as catalyst), ultrasonic oxidation, Fenton (Fe(II)/H2O2), and Fenton-like (Cu(II)/H2O2, V(IV)/H2O2) processes. It was found that the photocatalytic degradation of NB increased with decreasing pH, and the degradation rate also increased in the presence of TiO2/UV compared to UV irradiation alone. In addition, Ag loading on TiO2 dramatically reduced the degradation time. The ultrasonic degradation of NB was also studied using different initial dye concentrations at different pH values and amplitudes. Concentrations of Fe(II), Cu(II), V(IV) and H2O2 on degradation ratio were investigated. It is found that Fe(II) ion is more effective than Cu(II) and V(IV) ions in the degradation of NB.