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This article examines the utilization and advancements of constructed wetlands (CWs) in South Asia (SA), focusing on their roles, costs, and efficacy enhancements through pre- and post-treatment units for various pollutants. Notable findings include Phragmites and Canna species as commonly used macrophytes, achieving high removal rates for various pollutants. CWs consistently remove total suspended solids, biochemical oxygen demand, chemical oxygen demand, emerging contaminants, and antimicrobial resistant bacteria at substantial rates. Anaerobic baffled reactors are effective pretreatment devices for high-strength wastewater. Moreover, CWs exhibit lower operational and maintenance costs compared to conventional treatment methods. However, the bibliometric analysis reveals limited regional cooperation in SA. Key challenges identified include the absence of guidelines for media, vegetation, and maintenance. The review underscores the necessity for further research in optimizing CWs' efficiency through land area management, plant selection, and enhanced design and operation and maintenance protocols. [ABSTRACT FROM AUTHOR]

Amid escalating global challenges such as population growth, pollution, and climate change, access to safe and clean water has emerged as a critical issue. It is estimated that there are 4 billion cases of water-related diseases worldwide that cause 3.4 million deaths every year. This underscores the urgent need for efficient water quality monitoring and assessment. Traditional assessment techniques include laboratory-based methods that are manual, costly, time-consuming, and risky. Although some studies leveraged Internet of Things (IoT)-based systems to examine water quality, they only relied on a limited number of water quality parameters (and thus do not offer a comprehensive and accurate water quality assessment), mainly due to the technical difficulties to integrate multiple sensors to a single device. In fact, due to the issues of multimodality, heterogeneity, and complexity of data, the interoperability among sensors with various measurements, sampling rates, and technical requirements makes it very challenging to seamlessly integrate multiple sensors into one device. This study overcame these technical challenges by leveraging multisensor data fusion capabilities to develop an intelligent cloud-based IoT multimodal edge sensing device to provide an automated, real-time, and comprehensive assessment process of water quality. First, a total of nine water quality parameters were identified and considered. Second, the sensing device was designed and developed using an ESP32 embedded system, which is a low-cost, low-power system on a chip (SoC) microcontroller integrated with Wi-Fi and dual-mode Bluetooth connectivity by fusing data from six different sensors that measure the nine identified water parameters on the edge. Third, the overall water quality was evaluated using the National Sanitation Foundation Water Quality Index (NSFWQI). Fourth, a cloud-based server was created to publish the data instantly, and a graphical user interface (GUI) was developed to provide easy-to-understand real-time visualization and information of the water quality. The real-world applicability and practicality of the developed IoT-enabled sensing device was tested and verified in a pilot project (i.e., a case study) of a building located in Newark, New Jersey, for a duration of 6 months. This paper adds to the body of knowledge by being the first research developing a single IoT-enabled device that is capable of reporting NSFWQI in real-time based on 9 water quality indicators encompassing both physical [temperature, total dissolved solids (TDS), turbidity, and pH] and chemical [potassium, phosphorus, nitrogen, dissolved oxygen (DO), and 5-day biochemical oxygen demand (BOD5)] parameters. Thus, this study serves as a multifaceted improvement across different dimensions, fostering healthier, more efficient, and technologically advanced environments. [ABSTRACT FROM AUTHOR]

Pyridinic nitrogen vacancy in carbon nitride for photo-self Fenton-like purification of organic contaminants. [Display omitted] • Carbon nitride with pyridinic nitrogen vacancy was successfully prepared. • Pyridinic nitrogen vacancy promotes charge transfer and activating O 2 into H 2 O 2. • Pyridinic nitrogen vacancy accelerates carbon nitride to adsorb organic contaminants. • Photo-self Fenton-like reaction for photocatalytic degradation of organics. This work reports a carbon nitride with pyridinic nitrogen-vacancy (N 2C V-CN), which purifies organic contaminants via an in-situ photo-self Fenton-like reaction. Experiments and calculations demonstrated that the nitrogen-vacancy induces lone-paired (LP) and symmetry-unpaired electrons, promoting the formation of low-energy LP-π hybridized orbitals and helping to overcome the pairing energy required for oxygen to accept electrons. Furthermore, the nitrogen-vacancy accelerates film and intra-particle diffusion rates of organic contaminants on N 2C V-CN, creating beneficial conditions for reactive oxide species to mineralize organic contaminants. Under sunlight and atmospheric oxygen, a photo-self Fenton-like reaction involving proton-coupled electron transfer occurred on the surface of N 2C V-CN. Furthermore, by integrating photocatalysis with flocculation, about 99.1 % suspended substance, 45.5 % chemical oxygen demand, and 38.4 % biological oxygen demand were reduced from polluted river-water. Constructing N 2C V-CN and understanding its crucial role offer theoretical and methodological insights into the in-situ purification of contaminated water bodies. [ABSTRACT FROM AUTHOR]

The purpose of this research is to assess the efficacy of five distinct artificial intelligence model techniques: AdaBoost, Gradient Boosting, Tree, Random Forest, and KNN, to estimate the water quality parameters of dissolved oxygen (DO) and biochemical oxygen demand (BOD). The performance of each model was assessed using two datasets: Al-Muthanna Bridge and Al-Aammah Bridge on the Tigris River in Baghdad City. The data was randomly divided into two categories: 70% for training and 30% for testing. Principal component analysis (PCA) was used to identify the most effective input parameters for modeling DO and BOD. The four performance criteria -- coefficient of determination (R²), root mean square error (RMSE), mean absolute error (MAE), and mean square error (MSE) -- were applied in order to evaluate the models' effectiveness. It was demonstrated that the AdaBoost and Gradient Boosting models were superior for predicting DO and BOD. For DO prediction, the coefficient of determination R² of Gradient Boosting (AdaBoost) at Al-Muthanna Bridge and Al-Aammah Bridge were 0.994 (0.992) and 0.994 (0.991), respectively. For BOD prediction, the correlation coefficients R² of Gradient Boosting (AdaBoost) were 0.992 (0.982) and 0.989 (0.990), respectively. This study has shown that sophisticated machine learning techniques, such as gradient boosting and AdaBoost, are suitable for predicting water quality indices. They could also be helpful for predicting and managing the water quality parameters of different water supply systems in the future in water-related communities where artificial intelligence technology is still being thoroughly investigated. [ABSTRACT FROM AUTHOR]

This study aimed to determine the effect of bittern coagulant dosage and rapid stirring speed on reducing the concentrations of biological oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), and dye absorbance in batik industry wastewater, as well as to identify the optimum coagulant dosage and stirring speed. Wastewater samples were collected from a batik industry in the batik center of Sidoarjo, East Java, Indonesia. Dosage variations of 5%, 10%, 15%, and 20% were tested alongside rapid stirring speeds of 100 rpm, 130 rpm, and 160 rpm. The study was conducted on a laboratory scale using the jar test method. Initial wastewater characteristics showed BOD, COD, TSS, and dye absorbance concentrations of 185.68 ± 29.34 mg/L, 10.091 ± 363.24 mg/L, 2.231.33 ± 155.55 mg/L, and 0.212 ± 0.02, respectively. Statistical analysis using the Pearson correlation test and Two-Way ANOVA revealed that variations in coagulant dosage and stirring speed significantly impacted the reduction percentages of BOD, COD, TSS, and dye absorbance. The optimal coagulant dosage was found to be 5%, and the optimal stirring speed was 100 rpm, with reduction percentages for BOD, COD, TSS, and dye absorbance being 80.32%, 65.86%, 92.35%, and 70.77%, respectively. [ABSTRACT FROM AUTHOR]

The degradation of river ecosystems due to urbanization and industrial discharges is a pressing environmental issue affecting ecosystem health and sustainable human livelihoods. This study focuses on the Cikakembang River, a critical tributary of the Citarum River in West Java, Indonesia, which exemplifies these challenges with alarming pollution levels. Recent measurements revealed significant water quality degradation, with elevated concentrations of harmful pollutants far exceeding environmental safety thresholds. This study aimed to comprehensively assess the pollution levels at the river and identify viable mitigation strategies to address the river's deteriorating condition. This study utilized a robust methodology that combined water sampling, laboratory analysis, and the application of the QUAL2Kw model to simulate scenarios of pollution control. Results indicated critical levels of biochemical oxygen demand (BOD) and chemical oxygen demand (COD), with values reaching up to 60 mg/L and 150 mg/L, respectively, starkly illustrating the river's pollution severity. The proposed strategies, including ammonia concentration control, aerator placement, and integrated approaches combining wastewater treatment and upstream water conditioning, have demonstrated substantial pollutant reductions. These findings underscored the efficacy of combined pollution control measures and highlighted the challenges in fully achieving stringent environmental standards. The study thus recommends additional strategies, including regulatory adjustments and further refinement of pollution control measures, to meet the ambitious environmental goals set by the Indonesian Government for the Cikakembang River. The insights massed from this research provide a valuable framework for policy development and environmental management strategies aimed at revitalizing and sustaining the river's ecological health. [ABSTRACT FROM AUTHOR]

Olive mill wastewater (OMW) is a significant environmental pollutant due to its high organic load and toxicity, necessitating effective treatment methods. This study evaluates the impact of treating OMW through infiltration-percolation on the germination of cereal seeds, specifically durum wheat (Triticum durum Desf.) and barley (Hordeum vulgare L.). The treatment involved using sand filters combined with lime and eucalyptus sawdust. Key physicochemical parameters, including pH, electrical conductivity (EC), biological oxygen demand (BOD₅), mineral matter (MM), organic matter (OM), and total organic carbon (TOC), were analyzed for both untreated OMW and the filtrates produced by the treatment. The results showed that the use of lime, alone or with eucalyptus sawdust, in the filtration process significantly increased the pH and EC, while leading to a highly significant reduction in BOD5, MM, OM, and TOC. Germination tests indicated that the highest germination rates, 80% for both wheat and barley, were achieved with specific treatment filtrates. These findings suggest that infiltration-percolation is an effective method for reducing the pollutant load in OMW, making the treated wastewater potentially suitable for reuse in irrigation, thereby offering a sustainable approach to managing this industrial byproduct. [ABSTRACT FROM AUTHOR]

In light of the increasing water scarcity and the need for sustainable waste management, the use of landfill leachate for irrigation has emerged as both a solution and a concern, posing potential risks to soil health and plant vitality. This study examined the multifaceted impacts of leachate irrigation on the soil characteristics, plant growth, and enzymatic activities of Medicago sativa (M. sativa). By exposing alfalfa to different concentrations of leachate, we assessed the influence on heavy metal accumulation, physiological parameters, and enzyme functions. The physicochemical profile of the leachate indicated that the pH was within acceptable limits, but the chemical oxygen demand (COD), biochemical oxygen demand (BOD5), and concentrations of lead (Pb) and aluminum (Al) exceeded regulatory standards. Morphological parameters exhibited dual effects: stimulation at lower leachate doses and inhibition at higher leachate doses. Our findings show that soil acts as a buffer, reducing heavy metal uptake by plants. Enzymatic activities, including catalase, peroxidase, and succinate dehydrogenase, fluctuated significantly at higher leachate concentrations, indicating stress responses. This research underscores the interplay between leachate irrigation, plant physiology, and soil health, emphasizing sustainable management to optimize plant growth and minimize environmental impacts. It also stresses refining leachate application protocols to preserve soil and ecosystem health. [ABSTRACT FROM AUTHOR]

The simple design, compactness, simultaneous treatment of multiple contaminants, absence of chemical usage, minimal sludge formation (reducing secondary pollution), low maintenance cost, and versatility to operate in both batch and continuous modes make electrocoagulation (EC) a promising choice for treating various types of industrial wastewater. In this study, EC was employed in batch mode to treat produced water obtained from an oil drilling site, to reuse it for injection purposes in the reservoir. Produced water typically contains high levels of total dissolved solids (TDS), turbidity, chemical oxygen demand (COD), biological oxygen demand (BOD), and oil & grease (O&G) contaminants. High-performing aluminum (Al) electrodes were chosen due to their stability, conductivity, and, most significantly, their high capacity for generating aluminum hydroxide ([Al(OH)₃]ₙ) flocs, which serve as carriers for contaminant capture. This compound has demonstrated remarkable effectiveness in trapping the aforementioned contaminants from produced water under various operating conditions, including the number of electrodes, supplied current, and electrode configuration (bipolar and monopolar). The impact of several factors, including the number of electrodes (varying from 4 to 8), current density (varying as 16, 79, 158 A/m2), and electrode configuration (bipolar and monopolar), was studied at room temperature and 250 rpm agitation speed. Initial turbidity, COD, BOD, and O&G concentrations were measured at 38 NTU, 700.7 ppm, 120 ppm, and 32.8 ppm, respectively. The EC treatment exhibited removal efficiencies of 51% for TDS, 85% for turbidity, 78% for COD, 80% for BOD, and 85% for O&G using a monopolar configuration with 8 electrodes, and 59% for TDS, 90% for turbidity, 85% for COD, 84% for BOD, and 86% for O&G using a bipolar configuration with eight electrodes. Additionally, cost estimation, considering electrode dissolution rate and power requirements, was conducted for the operation of both configurations. [ABSTRACT FROM AUTHOR]

Marine pollution poses significant risks to both human and marine health. This investigation explores the limnological status of the Odisha and West Bengal coasts during the annual cruise program, focusing on the influence of riverine inputs on coastal marine waters. To assess this impact, physicochemical parameters such as pH, salinity, total suspended solids (TSS), dissolved oxygen (DO), biochemical oxygen demand (BOD), and dissolved nutrients (NO2-N, NO3-N, NH4-N, PO4-P, SiO4-Si, total-N, and total-P) were analyzed from samples collected along 11 transects. Multivariate statistics and principal component analysis (PCA) were applied to the datasets, revealing four key factors that account for over 70.09% of the total variance in water quality parameters, specifically 25.01% for PC1, 21.94% for PC2, 13.13% for PC3, and 9.99% for PC4. The results indicate that the increase in nutrient and suspended solid concentrations in coastal waters primarily arises from weathering and riverine transport from natural sources, with nitrate sources linked to the decomposition of organic materials. Coastal Odisha was found to be rich in phosphorus-based nutrients, particularly from industrial effluents in Paradip and the Mahanadi, while ammonia levels were attributed to municipal waste in Puri. In contrast, the West Bengal coast exhibited higher levels of nitrogenous nutrients alongside elevated pH and DO values. These findings provide a comprehensive understanding of the seasonal dynamics and anthropogenic influences on coastal water quality in Odisha and West Bengal, highlighting the need for targeted conservation and management efforts. [ABSTRACT FROM AUTHOR]

Background: Whey, which has high biochemical oxygen demand and chemical oxygen demand, is mass-produced as a major by-product of the dairying industry. Microbial fermentation using whey as the carbon source may convert this potential pollutant into value-added products. This study investigated the potential of using whey powder to produce α-ketoisovalerate, an important platform chemical. Results: Klebsiella oxytoca VKO-9, an efficient L-valine producing strain belonging to Risk Group 1 organism, was selected for the production of α-ketoisovalerate. The leucine dehydrogenase and branched-chain α-keto acid dehydrogenase, which catalyzed the reductive amination and oxidative decarboxylation of α-ketoisovalerate, respectively, were inactivated to enhance the accumulation of α-ketoisovalerate. The production of α-ketoisovalerate was also improved through overexpressing α-acetolactate synthase responsible for pyruvate polymerization and mutant acetohydroxyacid isomeroreductase related to α-acetolactate reduction. The obtained strain K. oxytoca KIV-7 produced 37.3 g/L of α-ketoisovalerate from lactose, the major utilizable carbohydrate in whey. In addition, K. oxytoca KIV-7 also produced α-ketoisovalerate from whey powder with a concentration of 40.7 g/L and a yield of 0.418 g/g. Conclusion: The process introduced in this study enabled efficient α-ketoisovalerate production from low-cost substrate whey powder. Since the key genes for α-ketoisovalerate generation were integrated in genome of K. oxytoca KIV-7 and constitutively expressed, this strain is promising in stable α-ketoisovalerate fermentation and can be used as a chassis strain for α-ketoisovalerate derivatives production. [ABSTRACT FROM AUTHOR]

In this work, biochars were used as adsorbents to remove Cu, Cd, and Zn ions in a real stabilized leachate from a controlled landfill. Oak fruit shells biochar (OFSBC) and date palm fibers biochar (DPFBC) were obtained by pyrolysis of oak fruit shells and date palm fibers at 700 °C and 400 °C, respectively. OFSBC and DPFBC showed well-developed structures and high specific surface areas (520.16 m2/g and 470.46 m2/g, respectively). Equilibrium adsorption of heavy metal ions on DPFBC and OFSBC occurred after 4 h and 2 h of stirring. The removal efficiencies of Cu, Cd, and Zn ions were 97.01%, 94.40%, and 80.59% with DPFBC and 90.10%, 88.33%, and 76.16% using OFSBC, respectively. The Avrami fractional order model was appropriate for describing kinetic adsorption. Increasing the dose of adsorbent improves heavy metal ion retention. Thermodynamic tests have proven the spontaneous and endothermic adsorption of these heavy metals. The electrostatic attraction, ion exchange, complexation, metal-π bending, and surface precipitation and pore filling were regarded as the most predominant heavy metal retention mechanisms from the landfill leachate onto the biochar surface. Separately, the DPFBC showed the best performance than OFSBC regarding the improvement of leachate quality. Chemical oxygen demand (COD), biological oxygen demand (BOD5), ammoniacal nitrogen (NH3-N), and phosphorus (P) were respectively removed at an efficiency of 53.57%, 29.17%, 36.07%, and 37.5%, respectively. Thus, the results allow highlighting that the adsorption on DPFBC and OFSBC can be an effective alternative in the practice of landfill leachate treatment. [ABSTRACT FROM AUTHOR]

Wetland ecosystems are vital for both biodiversity and communities that depend on them. The Ligawasan Marsh in the southern part of the Philippines is one of the most threatened wetlands in the country. Apart from increasing anthropogenic development, wetlands have faced warfare-driven threats that have hindered research and conservation efforts in the area for many decades. Our study is the first to investigate the patterns of physicochemical parameters, patterns of land use cover, and the relationship between land use change and marshland environmental status. We also developed the Marshland Impact Area (MARia) index to assess the potential impact contributions of the surrounding towns. We found a strong negative correlation between dissolved oxygen (DO) and indicators of pollution such as biochemical oxygen demand (BOD), chemical oxygen demand (COD), and heavy metals. Interestingly, we observed elevated levels of phosphate and mercury at all sampling sites in the Ligawasan Marsh. Our landscape-level modelling showed that these elevated levels are associated with expanding croplands and urbanisation surrounding the marsh. We found that the potential impact contribution of cropland and urbanisation from surrounding towns of the Ligawasan Marsh varied significantly, suggesting the importance of implementing local policies to reduce land use change impacts. With the current yet remaims limited knowledge and beyond safe pollution levels in the Ligawasan Marsh, it is crucial to implement collaborative and science-based governance to integrate conservation initiatives with the priorities of global targets, such as the Kunming-Montreal Global Biodiversity Framework, for a comprehensive and sustainable approach to Ligawasan Marsh conservation. [ABSTRACT FROM AUTHOR]

This study investigates the potential of a salt bridge‐mediated microbial fuel cell (MFC) for power generation and wastewater sludge treatment in breweries. Unlike traditional "one‐parameter‐at‐a‐time" methodologies, this study uses a three‐variable Box–Behnken design response surface methodology to optimize critical MFC operational parameters. The effects of parameters such as solution pH, salt bridge molarity, and temperature were studied in the range of 4 to 10, 1 to 5 M, and 20 to 45 g L−1. The optimum operating parameters were found to be solution pH of 5.853, salt bridge molarity of 3.343 M, and temperature of 32.5 °C for chemical oxygen demand and biological oxygen demand removal efficiencies of 92.485 % and 88.51 %, respectively. Temperature was found to be the most significant factor affecting the reactor's performance. [ABSTRACT FROM AUTHOR]

Introduction: With increasing age, patients experience a reduction in immunity and an increase in systemic illnesses. These factors significantly contribute to the occurrence of candidiasis in the oral cavity. New approaches to treating and preventing a wide range of oral disorders may become possible through host immunity modulation. Natural agents are preferred for complete denture wearers to prevent candidiasis, which is one of the leading causes of denture stomatitis. Aim: To assess the efficacy of herbal oral rinses (Triphala) and probiotics against Candida species in denture-wearing patients. Materials and Methods: This randomised double-blinded study clinical study was conducted in the Department of Prosthodontics at MM College of Dental Sciences and Research, Mullana, Ambala, Haryana, India, from August 2022 to January 2023. Ethical clearance was obtained and 60 patients were randomly divided into two groups (n=30): Group-A (Probiotics group) and Group-B (Triphala group). Sample collection was performed at baseline and after an 8-week experimental period. The collected samples were inoculated in Sabouraud Dextrose Agar with Chloramphenicol and incubated for 48 hours at 37°C±2°C in a Biological Oxygen Demand (BOD) incubator. The number of Candida colonies was scored and counted using a Digital Colony Counter, reported as Colony-forming Units (CFU) at baseline and after eight weeks. Data analysis was conducted using the Wilcoxon matched-pair test for comparisons within groups and the Mann-Whitney U-test for pair-wise comparisons (p<0.05). Results: The mean age of patients in Group-A was 61±3 years, while in Group-B it was 60±2 years. The mean CFU for the probiotics group was 44.70±72.5 and for the Triphala group, it was 79.60±58.7 before treatment. After treatment, the mean CFU for the probiotics group was 24.70±271.4 and for the Triphala group, it was 50.67±196.4. Although no significant difference (p-value>0.05) was observed between the two groups, both rinses proved effective against Candida species in denturewearing patients. However, the mean reduction in CFUs was significantly higher for Triphala (p-value=0.021). Conclusion: Both probiotics and Triphala showed a significant reduction in CFU after eight weeks of use. However, Triphala was more effective in reducing Candida compared to probiotics. Therefore, it can be considered an efficient agent for denturewearing patients against Candida species. [ABSTRACT FROM AUTHOR]

Anaerobic digestion (AD) is one of the most significant processes for treating fecal sludge. However, a substantial amount of microplastics (MPs) have been identified in septic tanks, and it remains unclear whether they impact the resource treatment of feces. To investigate this, polyethylene terephthalate (PET) was used as an indicator of MPs to study their effect on the anaerobic digestion of fecal sludge (FS). Two digestion systems were developed: FS mono-digestion and FS co-digestion with anaerobic granular sludge. The results indicated that the effects of PET varied between the two systems. PET inhibited volatile fatty acid synthesis in both systems, but the inhibition period differed. During mono-digestion, PET slightly increased gas and methane production, in contrast to the co-digestion system, where PET reduced methane production by 75.18%. Furthermore, in the mono-digestion system, PET increased soluble chemical oxygen demand and ammonia nitrogen concentrations while blocking phosphorus release, whereas the co-digestion system showed the opposite effects. Ultimately, the choice of digestion method is crucial for the resource utilization of septic tank sludge, and the impact of MPs on AD cannot be ignored. [ABSTRACT FROM AUTHOR]

Before 2016, the Eskişehir city landfill was an irregular landfill. Since then, it has been transformed into a regulated landfill. This study aimed to investigate the presence of pollution in the landfill drainage area. For this purpose, water samples were collected from the landfill drainage area and the Kadirbey Farm Spring, upstream of the landfill area, during the rainy and dry seasons of 2021. Analyses of the heavy metal content, total dissolved soil (TDS), chemical oxygen demand, biochemical oxygen demand, pH, phenol material content, ammonia nitrogen content, and conductivity were conducted on the samples. Electrical resistivity tomography (ERT) measurements were also performed along the stream bed. According to Turkish Soil Water Quality regulations, the TDS concentrations of all the samples, except one, were lower than the limits for class 3 water quality. The conductivity limits were within the acceptable range for class 3 water quality. The pH of the water samples was alkaline. The calculated leachate pollution index values indicated a pollution risk. The heavy metal pollution index values for the water samples were under 100. Additionally, 75% of the samples were in the very pure category according to the heavy metal evaluation index, with the remaining samples classified as slightly affected. According to the ERT measurements, soils with low resistivity near the landfill were notably laterally wider. The conductivity decreased with the increasing distance from the landfill site. Low resistivity zones, such as plumes, were disconnected from each other. The shape and volume of highly contaminated plumes decreased toward BH1. Based on the study outcomes, it is recommended to measure the water pollution parameters at periodic intervals within the landfill drainage area. [ABSTRACT FROM AUTHOR]

The present study tries to account for the diversity of desmids and also determine their distribution and abundance in Thattekkad Bird Sanctuary, situated in Ernakulam District, the first Bird Sanctuary in Kerala and lies within the geographical limits of 10°08′N 76°41′E and 10°13′N 76°68′E. The water samples collected were preserved and the physico-chemical parameters were analyzed using standard protocols. The study was carried out over a period of one year, from March 2022 to April 2023 in three seasons (pre-monsoon, monsoon, and post-monsoon) from the freshwater resources within the sanctuary like rivers, streams, and ponds. The following physico-chemical parameters of water were analyzed: the concentration of nitrates and phosphates, pH, temperature, dissolved oxygen (DO), biological oxygen demand (BOD), and turbidity. Desmids are unicellular algae that belong to conjugating green algae and occur exclusively in freshwaters, each cell consists of two almost symmetrical and often profusely sculptured segments. The current study identified a total of seventy-four taxa, which are distributed under four families and 18 genera. Predominant genera included were Cosmarium (21), Euastrum (12), and Staurastrum (8). Notably Heimansia pusilla, Euastrum praemorsum, Euastrum jenneri, Staurastrum saltans var. javanicum, Cosmarium clepsydra var. bicardia are new reports to India, five species are new reports to Kerala and all species being novel to Thattekkad Bird Sanctuary. The Shannon's diversity index is in the range of 0.8070 to 1.0151, and Simpson's Index range between 0.5051 to 0.6177. [ABSTRACT FROM AUTHOR]

The elevated level of pollutants in water highlights the urgency of effective wastewater treatment. Hence, the concern about the potential of microalgae as an economically and environmentally sustainable for wastewater treatment is addressed. Wastewater treatment using microalgae resulted in significant reductions in micropollutants by 82 % for chemical oxygen demand (COD) and biological oxygen demand (BOD). Iron (Fe) concentration was reduced by 99 %, while calcium (Ca) decreased by 25 %. Algal biomass obtained from wastewater is executed for biochar production and bio-stimulant preparation. Bio-stimulant treatment significantly enhanced seed germination and increased shoot and root lengths in maize (Zea mays) and beans (Phaseolus vulgaris) compared to the control. Conversely, seed germination was completely suppressed in both maize and beans in the presence of biochar of bio-stimulant treatment. The GC-MS and NMR analysis study revealed the presence of key compounds in the microalgal extract that have a great contribution to plant growth. Hence, the study concludes the multifaceted and potential application of microalgae as a remediation and bio-stimulant in a sustainable way. [Display omitted] • Integrated wastewater treatment, recycling and reuse technology (SDG 6a). • Utilization of wastewater treated C. sorokiniana for biochar & bio stimulant generation. • Bio-stimulant influenced germination and growth of Zea Maize and Phaseolus vulgaris. • GC-MS analysis identified key compounds in bio-stimulant for plant growth promotion. [ABSTRACT FROM AUTHOR]

In this study, we performed continuous high spatial resolution temperature measurements (six thermistors per 1–1.4 m water column) at six sites in three shallow temperate ponds during the warm season. These measurements were accompanied by experiments on plankton and sediment respiration rates, including the relationship between temperature and sediment respiration. Continuous temperature measurements allowed the construction of detailed stratification profiles, as well as the construction of seasonal trends in both plankton respiration and sediment oxygen demand, all with high temporal resolution (at 1-h intervals). A peak in plankton respiration was detected in mid-summer, while sediment oxygen demand showed two peaks, one before and one after the plankton peak. Sediment respiration made a significant contribution to total respiration in the water column and even exceeded plankton respiration during certain periods. The criteria for determining stratification and its thresholds, which differ for shallow and deep waters, are discussed in detail. We discuss the uncertainties in estimating respiration and explore contributing factors, such as limitation of sediment oxygen demand by low oxygen concentrations near the bottom and sampling time. In addition, we used statistics to analyze the effect of environmental factors on sediment surface oxygen. On the basis of statistical analysis, water column turbidity was found to be the most significant factor, followed by duration of stratification breakdown, dissolved oxygen (DO) in the surface layer, water column depth, chlorophyll a concentration in the water column, time of day, plankton respiration near the pond bottom, duration of stratification, and temperature near the pond bottom. [ABSTRACT FROM AUTHOR]

This study aimed to assess the trophic status of Pegametan Bay, Bali, Indonesia, as influenced by floating net cage aquaculture activities during June 2019 (dry season) and March 2021 (wet season). The trophic status was assessed using 24 parameters developed from a literature review, and water samples were collected from four observation stations. Data were analyzed using field measurements and laboratory analyses. The results showed that dissolved oxygen ranged between 2.6–9.1 mg/l in June 2019 and 3.4–7.7 mg/l during the March 2021 measurement period, salinity (33.6–34.4 ppt and 31–34 ppt), turbidity (0.77–6.33 FNU and 1.2–3.42 FNU), water clarity (4.18–11.92 m and 4.44–8.44 m), Biological Oxygen Demand (10.5–26 mg/l and 1–17 mg/l), Chemical Oxygen Demand (3.68–11 mg/l and 15.5–46.5 mg/l), chlorophyll-a (0.11–0.24 mg/l and 0–0.56 mg/l), Total Dissolved Solids (20,400–22200 mg/l and 21,300–53400 mg/l), ammonia (0.038–0.178 mg/l and 0.01–0.3 mg/l), nitrate (0.02–0.706 mg/l and 0.01–0.03 mg/l), orthophosphate (0.014–0.174 mg/l and 0.04–1.59 mg/l, and culturable bacteria (0–1.74 ∙ 105 CFU/mL and 0–1.61 ∙ 108 CFU/mL). Pegametan Bay exhibited a significant decrease in water quality between June 2019 and March 2021, with mesotrophic and eutrophic trophic states. The parameters determining changes in the trophic state of Pegametan Bay were orthophosphate, TSS, organic content, E. coli, Salmonella, and Vibrio. This trophic state assessment can be used for early detection, monitoring, water quality control, and eutrophication control, thereby ensuring sustainable aquaculture activities and optimal marine resource production. [ABSTRACT FROM AUTHOR]

Electro-Fenton process could remove pollutant in in tannery industry wastewater. The objectives of this is used to know the effect of electro-Fenton on, ammonia (NH3), chromium (III) (Cr(III), total suspended solid (TSS), biological oxygen demand (BOD), and chemical oxygen demand (COD) removal in tannery wastewater treatment. The voltage variation used to trigger the electro-Fenton reaction was 6 V, 8 V, and 10 V. Observation time at 0, 30, 60, 90, and 120 mins was used to see changes in the sample. The results obtained are electro-Fenton method has an effective time of 30 mins to removal efficiency of 60.7%, 32.9%, 72.8%, 53.4%, and 53.4% for NH3, Cr(III), TSS, BOD, and COD respectively. Pollution from tannery effluent can be eliminated to a sufficient extent using the electro-Fenton technique. [ABSTRACT FROM AUTHOR]

Morocco, like other arid and semi-arid countries, faces a growing water shortage, necessitating the exploration of alternative solutions. This study investigates the potential use of untreated urban wastewater for irrigation and environmental impact mitigation, focusing on El Jadida as a case study. Throughout the year 2023, from January to December, a comprehensive characterization of physico-chemical, heavy metal, and biological parameters of this unconventional water source was conducted to account for seasonal variations, particularly between rainy and sunny periods. Samples were collected at the inlet of the El Jadida wastewater pre-treatment plant (WWTP) to assess the city's net pollution levels. Results indicate high values for chemical oxygen demand (COD = 741 mg/L), biological oxygen demand (BOD5 = 344 mg/L), organic load (BOD5/COD ratio = 2.2), and biodegradability, suggesting a strong need for biological treatment. Despite compliance with discharge standards, concentrations of heavy metals such as mercury (Hg), cadmium (Cd), aluminum (Al), manganese (Mn), and fluoride ions (F-) exceed Moroccan irrigation water quality thresholds by 90%, 66.7%, 21.8%, 33.3%, and 86.1%, respectively. Therefore, advanced chemical treatment is highly recommended to mitigate environmental impact and ensure safe reuse for irrigation. The novelty of this study lies in evaluating the suitability of El Jadida's wastewater for irrigation and environmental impact mitigation, underscoring the critical need for effective treatment solutions to enhance water sustainability in Morocco. Future research will focus on optimizing water treatment processes. [ABSTRACT FROM AUTHOR]

In many developed and developing nations, lakes are the primary source of drinking water. In the current scenario, due to rapid mobilization in anthropogenic activities, lakes are becoming increasingly contaminated. Such practices not only destroy lake ecosystems but also jeopardize human health through water-borne diseases. This study employs advanced hierarchical clustering through multivariate analysis to establish a novel method for concurrently identifying significantly polluted lakes and critical pollutants. A systematic approach has been devised to generate rotating component matrices, dendrograms, monoplots, and biplots by combining R-mode and Q-mode analyses. This enables the identification of contaminant sources and their grouping. A case study analyzing five lakes in Bengaluru, India, has been conducted to demonstrate the effectiveness of the proposed methodology. Additionally, one pristine lake from Jammu & Kashmir, India, has been included to validate the findings from the aforementioned five lakes. The study explored correlations among various physical, chemical, and biological characteristics such as temperature, pH, dissolved oxygen, conductivity, nitrates, biological oxygen demand (BOD), fecal coliform (FC), and total coliform (TC). Critical contaminants forming clusters included conductivity, nitrates, BOD, TC, and FC. Factor analysis identified four primary components that collectively accounted for 85% of the overall variance. Following identification of pollution hotspots, the study recommends source-based pollution control and integrated watershed management, which could significantly reduce lake pollution levels. Continuous monitoring of lake water quality is essential for identifying actual contaminant sources. These findings provide practical recommendations for maximizing restoration efforts, enforcing regulations on pollutant sources, and improving water quality conditions to ensure sustainable development of lakes. [ABSTRACT FROM AUTHOR]

The swift pace of industrialization, urbanization, and burgeoning populations propel the surge in demand for manufactured goods and infrastructure. The wastewater produced during leather processing comprises a cocktail of organic and inorganic chemical contaminants that have the potential to affect the environment. This study focuses on conducting a comparative physico-chemical, analytical, in vitro, and in silico toxicity assessment and monitoring of leather effluent discharged from two different areas, namely, Dewas and Ranipet. The physicochemical analysis of collected effluents revealed higher levels of biochemical oxygen demand, chemical oxygen demand, total dissolved solids, total suspended solids, and heavy metals than the permissible limit fixed by the Central Pollution Control Board (CPCB). The X-ray powder diffraction analysis of both samples identified the existence of crystalline and amorphous phases. The functional composition of compounds was identified through the analysis of Fourier-Transform Infrared Spectroscopy, which revealed the existence of C-H, O–H, N–H, C = O, C=C, and C≡C stretching vibrations. A variety of compound derivatives, including amines, organic acids, organometallic compounds, alcohols, hydrocarbons, esters, aldehydes, ketones, aromatic, and organogermanium, were identified by Gas Chromatography-Mass Spectrometry. An assessment and monitoring of the phytotoxicity of effluent on the germination of Vigna radiata seeds reveals that (100%) of both Dewas and Ranipet leather effluents inhibited seed germination by 33.34% and 100%. The incorporation of Absorption-Distribution-Metabolism-Excretion-Toxicity (ADMET) analysis improved comprehension of the toxicity profiles of the GC–MS-identified compounds. Moreover, the result of docking studies revealed that cytochrome P450 showed the highest binding affinity towards 1,3-benzodioxol-2-one, hexahydro-cis with an affinity score of − 7.1 kcal/mol. The overall research revealed that the leather effluents from Dewas and Ranipet exhibit significant toxicity, highlighting the necessity of better wastewater management. In the future, innovative treatment methods and environmental friendly processes can be developed to minimize the detrimental effects of leather effluents. [ABSTRACT FROM AUTHOR]

Fish residing in the aquatic ecosystem are considered the best ecological indicator for monitoring environmental habitat. To evaluate the changes that occurred due to relative restoration in the ecological habitat, a study was conducted in the freshwater zone of the river Ganga between Buxar, Bihar, and Ballia, Uttar Pradesh, between July 2021 and July 2022. In the monitoring, the physico-chemical condition, as well as the food and feeding habits of the fish Gudusia chapra, were monitored with the help of various pollution evaluating indices, namely, the algal pollution index (API) for planktons, the comprehensive pollution index (CPI-WQI), and the National Sanitation Foundation Water Quality Indices (NSF-WQI) for water. The study showed that the relative restoration facilitated the amplification of the fish catch from 5.60 to 98.98% in two consecutive years. The reduction in the API (15 to 4) as well as CPI (0.80 to 0.72) during both years signified the reduction of the pollution status of the river in the region. The NSF-WQI also decreased from 88.27 to 79.27 from 2021 to 2022. The electivity index for the fish showed that fish preferred the groups Cyanobacteria, Rotifera, and Copepoda. The multivariate, as well as univariate analyses, revealed that the fish G. chapra is significantly influenced by multiple abiotic as well as biotic variables, among which the major contributors are riverine velocity, transparency, conductivity, pH, dissolved oxygen, total alkalinity, carbonate, bicarbonate, salinity, total hardness, calcium, silicate, and biochemical oxygen demand. [ABSTRACT FROM AUTHOR]

The Guanabara Bay hydrographic region (GBHR) has served as a central hub for human settlement and resource utilization throughout Brazil's history. However, the region's high population density and intense industrial activity have come at a cost, leading to a significant decline in water quality. This work aimed to identify homogeneous regions in GBHR according to water quality parameters in dry and rainy periods. The following water quality monitoring variables were monitored at 49 gauge stations: total phosphorus (TP), nitrate (NO3−), dissolved oxygen (DO), hydrogenionic potential (pH), turbidity (Turb), thermotolerant coliforms (TCol), total dissolved solids (TDS), biochemical oxygen demand (BOD), water temperature (Tw), and air temperature (Ta). The statistical analysis consisted of determining principal components, cluster analysis, seasonal differences, and Spearman's correlation. The water quality parameter correlations were not expressively influenced by seasonality, but there are differences in the concentrations of these parameters in the dry and rainy periods. In the dry period, urban pressure on water quality is mainly due to fecal coliforms. The resulting clusters delimited areas under urban, agricultural, and forestry influence. Clusters located in areas with high demographic density showed high concentrations of TCol and TP, while clusters influenced by forestry and agriculture had better water quality. In the rainy season, clusters with urban influence showed problems with TCol and TP, in addition to some characteristics in each group, such as high TDS, NO3−, and BOD. Forested areas showed high DO, and clusters under agricultural influence had higher concentrations of TCol, BOD, and NO3− concerning forested regions. The troubling state of sanitation in GBHR occurs in metropolitan regions due to lack of a formal sanitation system. [ABSTRACT FROM AUTHOR]

The expansion of urban areas has led to land-use changes that affect aquatic biodiversity and ecosystem processes through several ways, such as increased runoff, water pollution, habitat homogenization, and disturbance of the natural flow. It is well known that urbanization induces profound changes in freshwater macroinvertebrate communities, but relatively few studies have approached this topic using trait-based methods. This severely limits our ability to monitor and predict potential alterations of ecosystem processes. We here provide empirical evidence about the effects of urbanization-related changes on the trait composition and functional diversity of freshwater macroinvertebrates from Patagonia (Argentina). Macroinvertebrate sampling and environmental characterization were carried out in 13 study sites distributed across three water courses in the Futaleufú river basin. We found changes in environmental conditions over the urban impact gradient, in turn accompanied by variation in functional diversity and trait composition of aquatic macroinvertebrates. Specifically, we detected lower functional diversity in urban and post-urban reaches, mainly attributed to shifts in the distribution of taxa within the functional space, rather to the extirpation of functionally distinct taxa located at the edges of it (i.e., functional evenness and dispersion decreased, but functional richness remained constant). We also found signs of functional homogenization at the most impaired sites, where gatherers and tegument-breathing taxa dominated. These changes were mainly explained by conductivity, biological oxygen demand, and oxygen levels in the water column. [ABSTRACT FROM AUTHOR]

Following the Environmental Kuznets Curve hypothesis, an inverted U-shaped relationship is expected between economic growth and water utilization and pollution. As economic growth increases, so do water use and pollution. However, above a certain growth level (turning point), further growth has beneficial impacts, using less water and improving its quality. Recently, N-shaped relationships seem to prevail over inverted U curves — there is a rebound effect. However, the empirical evidence shows conflicting results, partly explained by the mobility and aggregation of economic activities across a large space (the whole country). Accordingly, we build a unique dataset with measures of water use (the ratio of water withdrawals to renewable water resources) and pollution (biological oxygen demand) to estimate water utilization and pollution equations using panel data from the 32 Mexican states (2005–2020). The article's contributions are threefold. First, it introduces methodological innovations to address endogeneity using advanced panel data econometric techniques. Second, it provides new insights into the economic growth-water relationship, identifying N-shaped patterns for water use and inverted N-shaped patterns for water pollution. Third, it discusses policy implications and future research directions in environmental management and sustainable development. The findings suggest improvements for inter-regional water trade and indicate that economic growth may lead to sustainable water pollution patterns, highlighting the potential for regulatory interventions to mitigate pollution and promote efficient water use. [ABSTRACT FROM AUTHOR]

The water quality index is a grading system for displaying data on water quality and comparing different types of water. Freshwater is important for biological needs and is an important surface for integrated environmental management and long-term development. Based on the water quality index, the current study gives a glimpse into the Umtrew river's water quality (WQI). Water samples were taken monthly intervals from 6 different stations along the full stretch of the Umtrew river for 12-month period (January 2019 to December 2019). To construct the water quality index, seven water quality parameters like pH, Eclectic Conductivity (EC), Total Dissolved Solids (TDS), Biochemical Oxygen Demand (BOD3), Dissolved Oxygen (DO), Total Hardness (TH) and Total Alkalinity (TA) were examined (WQI). The average WQI value at the upstream reference site was fell under the category from poor to very poor water quality. The WQI value in the downstream water was observed >100 which indicates the water required proper treatment before using for any purpose. [ABSTRACT FROM AUTHOR]

Purpose: Fresh palm oil-mill effluent (POME) is toxic and when added to agricultural soils often inhibits plant growth. In this study, the prospects of temporal fermentation of POME with aging in enhancing its organo-fertilizer value before application to low-fertility soils were evaluated. Method: Fresh and aged (6-12 months old) POME were used to grow tomatoes at 0, 25, 50, 75 and 100% in potted soils from a fallow land. After 28 days, tomato growth attributes were used to index phytotoxicity, while soil physicochemical properties were determined. Results: The fresh-aged POME ranges for pH, ash, organic matter, calcium, dissolved oxygen and biological oxygen demand were 7.00-8.45, 0.89-12.29%, 2.95-30.77%, 41.36-70.44 mg/l, 11.80-14.20 and 600-720 mg/l, respectively. Soil pH, organic matter, total N, available P and exchangeable bases increased due to POMEfresh and POMEaged, with optimal rates within 25-75% and 75-100%, respectively. Apparent cation exchange capacity was highest at 50% of POMEaged. Soil pH, total N and available P in = 25% POMEaged were rather high for tomato; so, optimal agronomic rate was 25%, beyond which POMEfresh and POMEaged caused control-like reductions and marginal increases in seedlings growth, respectively. Relative increases in both soil and crop parameters in the amended over the control were greater in POMEaged than POMEfresh treatments, and reflected increases in soil pH, P release and exchange of plant-nutrient cations. Conclusion: Aging-associated fermentation of POME could valorize it as organo-fertilizer for increased arable crop production in low-fertility soils. Controlled addition of aged and particularly fresh POME to these soils could avert inimical soil reactions, excessive nutrients mineralisation and/or growth inhibition, with the suggested agronomically optimal concentration being 25%. [ABSTRACT FROM AUTHOR]

This study aims to investigate the effect of different seasons (where the temperature would be different) on the performance (phosphorous, nitrogen, and organic matter removal) of sequencing batch reactor (SBR) based wastewater treatment plants. The modified activated sludge model 2D (ASM2d) module, including the microbial kinetics is used to simulate the enhanced biological phosphorus removal (EBPR) SBR process and the temperature is chosen between 10 and 33°C. Influent data from two distinct wastewater treatment plants located in India and Europe are considered. The investigation of the kinetic variables is performed over a wide temperature range, and significant increases are seen as the temperature rises. The effluent parameters are within the government regulations. It is clear that an increase in temperature results in better effluent quality with reduced values of chemical oxygen demand (COD), biological oxygen demand (BOD), ammonium nitrogen and ammonium ions (NH4), and total nitrogen (TN) and a slight increase in total phosphorus (TP) and total suspended solids (TSS). According to the current findings, as the temperature changes from low to high levels, the values of COD, BOD, TN, and NH4 decreased by 2.50, 14.92, 5.80, and 9.90% respectively, for Indian data. There is a slight increase of 1.07% in the TSS profile. In conclusion, this study highlights the importance of considering the effect of different climatic conditions on the performance of SBR-based wastewater treatment plants. [ABSTRACT FROM AUTHOR]

Food and dairy processing industries consume large quantities of clean water for various processes throughout the plant operations and consequently generate large amounts of wastewater. The objective of this study is to treat the wastewater of food and dairy industries using ZnO nanoparticles (ZnO NPs) to control the pH level and reduce contamination levels. The wastewater from three industries was tested for pH, total dissolved solids (TDS), turbidity, Chemical Oxygen Demand (COD), and Biochemical Oxygen Demand (BOD). The ZnO NPs are prepared with an average size of less than 100 nm by using a simple precipitation method. The obtained particles were characterised by X-Ray Diffraction (XRD), and Scanning Electron Microscope (SEM) proving the nano size of Zinc Oxide nano particles. The effluents have been treated with the ZnO NPs by varying doses resulting in reducing all contaminants to an acceptable level as recommended by concerned environmental organisations. [ABSTRACT FROM AUTHOR]

Inadequate energy management leads to more emission exposure, which causes climate change, severe environmental contamination, and human health risks. Therefore, the World Health Organisation (WHO) monitors universal efforts to prevent emissions and encourages governments to develop industries to transform the green economy. During the current study, the energy and cost variation was observed through three years (2020, 2021, and 2022) at a surface water plant in southern Egypt. Consistent with applying operation strategies that met convenient standard operating procedures (SOPs) during 2021 and 2022. Energy consumption was reduced by 13% to 17%, and the cost decreased by 5% to 12% for 2021 and 2022, respectively. These energy and financial savings should be considered as an influence of the water safety plans (WSPs). Detrended correspondence analysis (DCA) was utilised to identify the mechanism of energy consumption and its impact on the cost during the study period. The finding proves that the energy and cost rise is related to increased water demand during the summer months, periodic/emergency maintenance, and comprehensive cleaning activities. WSPs were applied to control biological oxygen demand (BOD), chemical oxygen demand (COD), and oil and grease (O & G) that show increasing values than Egyptian law. [ABSTRACT FROM AUTHOR]

Corn is the second most cultivated crop in Brazil, the number-one country in pesticide consumption. Chemical control of weeds is performed using herbicides such as S-metolachlor with pre- and post-emergence action and thus the toxicity of herbicides constitutes a matter of great concern. The present investigation aimed to examine the effects of an S-metolachlor-based herbicide on Lactuca sativa L. (lettuce) and Zea mays L. (maize) utilizing various bioassays. The test solutions were prepared from commercial products containing the active ingredient. Seeds from the plant models were exposed in petri dishes and maintained under biochemical oxygen demand (BOD) at 24°C. Distilled water was negative and aluminium positive control. Macroscopic analyses (germination and growth) were conducted for both plant species, and microscopic analysis (cell cycle and chromosomal alterations) were performed for L. sativa root tip cells. Detrimental interference of S-metolachlor-based herbicide was noted with lettuce for all parameters tested reducing plant germination by over 50% and the germination speed by over 45% and showing a significant decrease in mitotic index, from 16.25% to 9,28% even on the lowest concentration tested. In maize, there was no significant interference in plant germination; however, speed of germination was significantly hampered, reaching a 51.22% reduction for the highest concentration tested. Data demonstrated that the herbicide was toxic as evidenced by its phyto- and cytotoxicity in L. sativa L. and Z. mays L. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

This study investigated the efficacy of membrane bioreactor (MBR) technology in treating saline industrial wastewater, focusing on the impact of the organic loading rate (OLR) and the food-to-microorganism (F/M) ratio on treatment performance. This research utilized saline industrial wastewater from Al-Hasa, which had salinity levels ranging from 5000 to 6900 mg/L. It explored treatment processes at varying Chemical Oxygen Demand (COD) concentrations of 800, 1400, and 2000 mg/L, corresponding to an OLR of 0.80 ± 0.05, 1.41 ± 0.07, and 1.98 ± 0.12 g COD/L, respectively. The average F/M ratios used were 0.20, 0.36, and 0.50 g COD/g MLSS·d, maintaining a constant Sludge Residence Time (SRT) of 12 days, a hydraulic retention time (HRT) of 24 h (hrs.), and a flux of 10 L/m2·h. The MBR system demonstrated high COD removal efficiencies, averaging 95.7 ± 1.6%, 95.5 ± 0.4%, and 96.1 ± 0.3%, alongside Biochemical Oxygen Demand (BOD) removal rates of 98.3 ± 0.2%, 99.8 ± 0.1%, and 98.5 ± 0.1%, respectively. However, an increased OLR led to elevated residual COD and BOD levels in the treated effluent, with COD concentrations reaching 34.2 ± 12.8, 63.3 ± 5.9, and 76.5 ± 5.4 mg/L, respectively. This study also reveals a significant decline in ammonia and Total Kjeldahl Nitrogen (TKN) removal efficiencies as OLR increases, dropping from 96.1 ± 0.5% to 80.2 ± 0.9% for ammonia and from 83.8 ± 3.4% to 65.8 ± 2.3% for TKN. Furthermore, higher OLRs significantly contribute to membrane fouling and elevate the transmembrane pressure (TMP), indicating a direct correlation between OLRs and operational challenges in MBR systems. The findings suggest that for optimal performance within the Saudi disposal limits for industrial wastewater, the MBR system should operate at an F/M ratio of ≤0.33 g COD/g of Mixed Liquor Suspended Solid (MLSS)·d. This study underscores the critical role of the OLR and F/M ratio in treating saline industrial wastewater using MBR technology, providing valuable insights for enhancing treatment efficiency and compliance with environmental standards. [ABSTRACT FROM AUTHOR]

The Xiao Bei mainstream, located in the middle reaches of the Yellow River, plays a vital role in regulating the quality of river water. Our study leveraged 73 years of hydrological data (1951–2023) to investigate long-term runoff trends and seasonal variations in the Xiao Bei mainstream and its two key tributaries, the Wei and Fen Rivers. The results indicated a significant decline in runoff over time, with notable interannual fluctuations and an uneven distribution of runoff within the year. The Wei and Fen Rivers contributed 19.75% and 3.59% of the total runoff to the mainstream, respectively. Field monitoring was conducted at 11 locations along the investigated reach of Xiao Bei, assessing eight water quality parameters (temperature, pH, dissolved oxygen (DO), chemical oxygen demand (COD), ammonia nitrogen (NH3-N), total phosphorus (TP), permanganate index (CODMn), and 5-day biochemical oxygen demand (BOD5)). Our long-term results showed that the water quality of the Xiao Bei mainstream during the monitoring period was generally classified as Class III. Water quality parameters at the confluence points of the Wei and Fen Rivers with the Yellow River were higher compared with the mainstream. After these tributaries merged into the mainstream, local sections show increased concentrations, with the water quality parameters exhibiting spatial fluctuations. Considering the mass flux process of transmission of the quantity and quality of water, the annual NH3-N inputs from the Fen and Wei Rivers to the Yellow River accounted for 11.5% and 67.1%, respectively, and TP inputs accounted for 6.8% and 66.18%. These findings underscore the critical pollutant load from tributaries, highlighting the urgent need for effective pollution management strategies targeting these tributaries to improve the overall water quality of the Yellow River. This study sheds light on the spatiotemporal changes in runoff, water quality, and pollutant flux in the Xiao Bei mainstream and its tributaries, providing valuable insights to enhance the protection and management of the Yellow River's water environment. [ABSTRACT FROM AUTHOR]

The Gd-doped ZnO/SnO2 nanocomposites with various atomic percentages (0, 0.5, 0.8, and 1.2 at%) of gadolinium (coded as GdZS0, GdZS1, GdZS2, and GdZS3) was synthesis via the sol–gel method and explored for photodegradation against dye solutions exposing solar light irradiation. The synthesized nanocomposites were characterized employing the XRD, FTIR, FE-SEM, Raman spectroscopy, BET analysis and UV–Vis spectrophotometer. The FE-SEM results indicated that the formation of nanoparticles to nanoflowers covered with Gd ions was observed with an increased doping concentration of Gd. The optical bandgap was evaluated and found in the range of 3.21–3.27 eV for GdZS nanocomposites. The GdZS nano-photocatalysts were investigated against the degradation of different organic dyes and GdZS3 shows the highest degradation efficiencies of 99.3%, 98.3% and 99.4% towards MO, MB and RhB dyes, respectively at neutral pH in aqueous media. Before and after photodegradation. Biological oxygen demand and chemical oxygen demand tests to make estimations of mineralization. The investigations are very promising for the degradation process in rare earth doped metal oxide nanocomposites. A plausible photodegradation mechanism of synthesized nanocomposites under investigation has also been proposed. [ABSTRACT FROM AUTHOR]

This study highlights the importance of managing fishpond effluent to minimize its impact on aquatic environments. Fish effluents are a major concern worldwide in aquatic environments. It also provides information on the impacts of effluents on the water quality index of streams when released into aquatic environments. Streams and fishponds were sampled bimonthly for two annual cycles, covering different sampling stations both upstream and downstream of the fishpond effluents at 50-m intervals. Water quality parameters associated with in situ conditions were determined in the field. In the laboratory, other physicochemical parameters were determined via proper standard protocols. The results of the study revealed that water quality parameters such as turbidity, total suspended solids, total solids, conductivity, total dissolved solids, dissolved oxygen, biological oxygen demand and organic matter recorded in water samples collected from 50 m upstream at the point of effluent discharge were significantly (p < 0.05) different from those recorded at other sampling stations. The WQI value of the discharge point was higher than the WQI recorded in both the upstream and downstream sections of the stream. The findings of this study showed that the point of discharge of fishpond effluents is particularly concerning for the receiving stream compared with other sampling points. This localized area has experienced marked deterioration in water quality, posing significant threats to the health and biodiversity of aquatic ecosystems. The effluent's impact, though slight when dispersed in the receiving waterbody, underscores the necessity for adequate management practices to mitigate its adverse effects. Effective strategies, including regular monitoring, effluent treatment, and sustainable pond management, are imperative to ensure the long-term health and resilience of the aquatic environment. [ABSTRACT FROM AUTHOR]

The tannery industry produces one of the worst contaminants, and unsafe disposal in nearby waterbodies and landfills has become an imminent threat to public health, especially when the resulting multidrug-resistant bacteria and heavy metals enter community settings and animal food chains. In this study, we have collected 10 tannery wastewater (TWW) samples and 10 additional non-tannery wastewater (NTW) samples to compare the chemical oxygen demand (COD), pH, biological oxygen demand (BOD), dissolved oxygen (DO), total dissolved solids (TDS), chromium concentration, bacterial load, and antibiotic resistance profiles. While COD, pH, and chromium concentration data were previously published from our lab, this part of the study uncovers that TWW samples had a significantly higher bacterial load, compared to the non-tannery wastewater samples (5.89 × 104 and 9.38 × 103 cfu/mL, respectively), higher BOD and TDS values, and significantly lower DO values. The results showed that 53.4, 46.7, 40.0, and 40.0% of the TWW isolates were resistant to ceftriaxone, erythromycin, nalidixic acid, and azithromycin, respectively. On the other hand, 20.0, 30.0, 50.0, and 40.0% of the NTW isolates were resistant to the same antibiotics, respectively. These findings suggest that the TWW isolates were more resistant to antibiotics than the NTW isolates. Moreover, the TWW isolates exhibited higher multidrug resistance than the NTW isolates, 33.33, and 20.00%, respectively. Furthermore, spearman correlation analysis depicts that there is a negative correlation between BOD and bacterial load up to a certain level (r = − 0.7749, p = 0.0085). In addition, there is also a consistent negative correlation between COD and bacterial load (r = − 0.7112, p = 0.0252) and TDS and bacterial load (r = − 0.7621, p = 0.0104). These findings suggest that TWW could pose a significant risk to public health and the environment and highlight the importance of proper wastewater treatment in tannery industries. [ABSTRACT FROM AUTHOR]

Effluent reuse is a rapidly growing field of research where assessing the quality of effluent is one of the focus areas. This research examines the viability of using wastewater in agriculture by testing an integrated Upflow Anaerobic Sludge Blanket (UASB) reactor with a trickling filter (TF) system during the dry season. Compliance monitoring was conducted for 30 days from May 11 to June 9 of 2021. Samples were collected, handled, and analyzed following standard wastewater analysis procedures for biological oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), volatile suspended solids (VSS), cations, anions, heavy metals, E. coli, and helminth egg. The UASB-TF system in Kality wastewater treatment performed well in removing COD, BOD5, and TSS with average removal rates of 80.5%, 82.9%, and 80.9%, respectively, compared well with similar treatment configurations. The effluent quality satisfied the national inland discharge limit with a residual concentration of 125.1 mg/L for COD, 61.7 mg/L for BOD5 and 85.8 mg/L for TSS. On the other hand, high concentrations of chromium, nitrate-nitrogen, and helminth egg count restricted effluent reuse for agricultural purposes due to high health risks and environmental contamination. We found out that discharging industrial sewage into the domestic sewer network could inhibit microbial growth and affect the biological treatment processes. Furthermore, adopting integrated treatment systems in developing countries might face operational challenges and monitoring nitrate, helminth egg, and heavy metals would help provide timely operational feedback. An appropriate tertiary treatment unit—constructed wetlands or polishing ponds—is therefore needed to be introduced to ensure effluent reuse for agricultural purposes. [ABSTRACT FROM AUTHOR]

This study was carried out to investigate the effects of the wastewater treatment plant located in the Aziziye District of Erzurum Province on the Karasu River. For this purpose, water samples were taken from 3 stations for a year between 2022-2023. The mean water temperature was measured in situ during sampling as 13.8 ˚C, the mean pH value was 7.7, the mean electrical conductivity was 403 μs/cm, and the mean dissolved oxygen value was 6 mg/l. The mean total suspended solid (TSS) amount was determined as 46.7 mg/l, the mean chemical oxygen demand (COD) concentration was 28.9 mg/l, the mean biological oxygen demand (BOD) concentration was 18.5 mg/l, the mean total nitrogen (TN) concentration was 4.47 mg/l, the mean nitrate (NO3) concentration was 5.35 mg/l, the mean nitrate nitrogen (NO3-N) concentration was 1.21 mg/l, the mean total hardness (TH) was 155 mg/l, the mean ammonium (NH4) concentration was 2.75 mg/l, and the mean ammonium nitrogen (NH4-N) concentration was 2.16 mg/L. As a result, it was determined that the Wastewater Treatment Plant positively affected some water quality parameter values of the Karasu River. [ABSTRACT FROM AUTHOR]

This study aimed to assess the feasibility of employing indigenous cyanide-degrading bacterial strains for the treatment of cassava mill effluent (CME) in Nigeria, a hazardous waste material posing significant public health risks. The physicochemical properties and heavy metal concentrations in CME were determined through standard methodologies. Cyanide-degrading bacteria were isolated, characterized, and identified using molecular techniques. These strains were immobilized within a porous network of cross-linked biochar, confirmed through SEM imaging, and evaluated alongside free cells for CME bioremediation. Multiple variables were examined to assess the effluent's pollution load, including pH, electrical conductivity (EC), chemical oxygen demand (COD), biochemical oxygen demand (BOD5), total dissolved solids (TDS), nitrate (NO3), phosphate (PO4), and cyanide levels, falling within respective ranges of (4.00-4.02), (2394-2618 S/cm), (985-1219 mg/L), (1556-1667 mg/L), (3459-3705 mg/L), (2709-2812 mg/L), (251-311 mg/L), (87.25-118 mg/L), and (25.00-28 mg/L). Copper was the most prevalent heavy metal in the effluent, while chromium was detected at the lowest levels, with mean values of 10.00-12.39 mg/L and 0.00-0.27 mg/L, respectively. The study revealed severe contamination of the effluent, above the Federal Environmental Protection Agency (FEPA) threshold limit. The 16S rDNA of the cyanide degrading bacteria were deposited at the NCBI database and the following GenBank accession numbers were assigned (MK71248O, MK71281, MK712482, and MK712483) for Pseudomonas putida, Bacillus subtilis, Alcaligenes faecalis and Leuconostoc mesenteroides respectively. Results of the bioremediation approach demonstrated a substantial reduction in physicochemical parameters and heavy metal contents, indicating a promising biological treatment strategy to mitigate CME's adverse effects on public health. In conclusion, despite elevated physicochemical parameters and heavy metal concentrations in CME, this study offers a promising avenue for employing biological treatments to mitigate environmental and public health impacts. Further research and application of this technique hold substantial potential for cassava mill effluent management in Nigeria and other regions facing similar challenges. [ABSTRACT FROM AUTHOR]

This research focuses on the impact of pulsed feeding of corn residues on biogas production from pig manure. It also analyzes the properties and microbial diversity in the resulting product. The study highlights the increasing global demand for pork and the resulting environmental challenges, such as effluent management, and suggests that biogas production can be a sustainable solution. The research was conducted at a model farm in Argentina and involved evaluating biogas production and microbial variability at different stages of the pulsed feeding process. The results showed a significant decrease in the chemical and biochemical oxygen demands after the degassing process, indicating a reduction in organic matter. The biogas composition improved with an increase in methane and a reduction in volatile fatty acids. There was also an increase in biogas and methane production and a decrease in methane production lag time, indicating an improvement in anaerobic digestion efficiency. Microbiological analysis revealed a reduction in microbial diversity during pulsed feeding, indicating the adaptation of the microbial community to new conditions. Overall, the study demonstrates the potential of pulsed feeding of corn residues to enhance biogas production from pig manure, with significant implications for effluent management in pork production and sustainable biogas production. [ABSTRACT FROM AUTHOR]

The potential for corrosion and odor emissions from a combined sewer interceptor system in Northwest Chicago was investigated. Seven manholes along the interceptor system were selected as monitoring locations, and eight critical physical-chemical and biological parameters were measured semiweekly at each location for four weeks during the morning and afternoon hours. Statistical analyses were performed to determine the diurnal variability of 5-day biochemical oxygen demand (BOD5), as well as the variability of total sulfide with respect to BOD5 and the sewer flow rates. Subsequently, the Pomeroy–Parkhurst mathematical model was used to predict the change in total sulfide concentration in a mile-long segment of the interceptor system. The model was calibrated by modifying the sulfide flux coefficient in the generation term to reflect the conditions in these interceptors, such that the measured values and model predictions were in agreement. A strong linear relationship between the system's wastewater flow and water quality characteristics and the modified sulfide flux coefficient was found (R2=0.828). With limited wastewater characteristic data, the modified Pomeroy–Parkhurst model can be used in predicting the change in total sulfide concentrations for this interceptor. [ABSTRACT FROM AUTHOR]

The textile dying industry is one of the most important industrial sectors in Bangladesh. The discharged untreated effluent from different industries adds to the environment a wide variety of harmful chemicals, which cause severe damage to the water. The present study aimed to characterize the discharged effluent surrounding the areas of cottage textile dyeing industries. The effluent samples were collected from different locations of the four upazilas (administrative regions) in Sirajganj district in three seasons, namely the pre-monsoon, monsoon, and post-monsoon, covering two years. The study considered the major physicochemical and chemical parameters, including biological oxygen demand (BOD), chemical oxygen demand (COD), heavy metals, and anions. The analysis results showed that most of the physicochemical parameters, including EC, pH, TDS, TSS, turbidity, BOD, COD, organic matter (OM), total hardness (TH), the cationic and anionic parameters, and trace metals, including Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Cd, and Pb, in effluent samples exceeded the Department of Environment, Bangladesh (DoE-BD) standard, 2008. The most toxic heavy metals, such as Cr, Mn, Cd, and Pb, were found to be higher than the standard permissible limit in all of the collected samples, indicating heavy metal pollution in the area. The analysis results of the Fourier-transform infrared spectroscopy (FTIR) showed that the effluent samples contained toxic functional groups, like azo, cyano, etc., indicating higher levels of pollution due to the discharge of untreated textile dyeing effluent. [ABSTRACT FROM AUTHOR]

The metropolis of Kolkata stands uniquely positioned to implement a natural sewage treatment paradigm through the utilization of waste stabilization ponds, specifically within the East Kolkata Wetlands (EKW). These shallow oxidation ponds harness solar irradiation and algae bacteria symbiotic processes to effectively treat incoming sewage. Concurrently, nutrient-rich effluents are assimilated through fish production, converting available nutrients into protein--a hallmark of nature-based treatment. A portion of raw sewage is used to cultivate a chunk of vegetables before treatment in fish ponds, and the reclaimed water after treatment is used for vegetable and paddy cultivation downstream. This investigation explains the delineation of a sewage flow system to EKW, a Ramsar-designated site. Substantively, it offers quantitative insights into the sewage volumes and quality undergoing treatment. The sewage flow is higher in the winter months (909.07 MLD) compared to the summer months (709.34 MLD). In general, the sewage from the Kolkata city flowing to the EKW is moderately polluted. Extensive scrutiny of sewage from pond inlets and outlets serves as a quantitative metric for evaluating treatment efficacy. EKW efficiently treats the sewage, demonstrating 59.1% Biological Oxygen Demand (BOD) removal and a 99.28% reduction in fecal coliform. The natural treatment system excels in removing ammoniacal nitrogen (80.38%) and phosphate (90%). The treated water's quality along the EKW boundary, culminating at the Kulti Gong River discharge point, was systematically assessed. Analytical findings indicate that all measured concentrations in the treated water adhere to prescribed inland surface water discharge standards prescribed by the Central Pollution Control Board, India, barring a marginal elevation in BOD during winter. Evidently, the EKW system adeptly manages substantial sewage volumes, fostering efficient treatment while concurrently facilitating resource recovery through fish production, yielding economic dividends. Despite its substantial land footprint, preserving this inherently sustainable wastewater management paradigm is imperative. [ABSTRACT FROM AUTHOR]

Intensifying anthropogenic disturbances have caused water pollution in China in recent decades. China has a vast territory with diverse climate conditions, land use types, and human activities, leading to significant water quality variability. However, few studies have investigated nationwide spatiotemporal patterns of key water quality parameters. In this study, we analyze monthly water quality observations from 3647 gauge stations to understand how water quality changes over time and space in China. We group the stations by water resource regions and adopt Python and SPSS to analyze the spatiotemporal variability and intercorrelations of eight water quality parameters. Results indicate that the concentrations of biochemical oxygen demand of 5 days (BOD5), chemical oxygen demand (COD), dissolved oxygen (DO), ammonia nitrogen (NH3-N), total nitrogen (TN), and total phosphorus (TP) show similar spatial patterns, with higher concentrations in the northern parts than the southern regions of China. The concentrations of COD and TP are higher in the rainy season than in the dry season, while DO, NH3-N, and TN show the opposite seasonal patterns. Strong positive correlations were found between BOD and COD, NH3-N and TP. The annual cumulative distribution figures demonstrate that all parameters showed slightly lower concentrations in 2022 and 2023 than in 2021, except for DO and TN. The TN/TP ratios across different water resource regions in China are significantly higher than 16, indicating that phosphorus is the limiting factor of eutrophication. This investigation provides a comprehensive understanding of the spatiotemporal variability of water quality parameters across China. The results of this study are highly valuable for investigating mechanisms regulating water quality across large spatial scales, thus providing valuable implications for improving water quality and mitigating water pollution. [ABSTRACT FROM AUTHOR]