High Turbidity Research Articles

Blackwater peat swamps in Peninsular Malaysia support diverse aquatic species including cryptic and elusive taxa. However, extreme environmental conditions such as high acidity, turbidity and organic content hinder biodiversity monitoring, leaving these ecosystems largely understudied. Environmental DNA (eDNA) offers a non-invasive approach for species detection, thus providing a promising tool for biodiversity assessment. This study investigates the influence of water filtration volume and hydrological factors on DNA concentration in a blackwater peat in Dungun, Terengganu. Water sampling was conducted between November and December 2023 at three substations—designated as upper (A), middle (B) and lower (C) which spaced at 50-meter intervals with five replicate samples filtered from each substation. A total of 2L blackwater per station was filtered using a 0.45 µm mixed cellulose ester (MCE) membrane and an oil-free vacuum pump. eDNA was extracted using a modified DNeasy® Blood & Tissue Kit, quantified with a NanoDrop spectrophotometer and assessed through gel electrophoresis. Results showed that eDNA concentration varied significantly across stations and was influenced by the filtered water volume. The highest eDNA concentrations were recorded at the middle stretch (B1: 480 mL, 32.00 ng/μL; B2: 480 mL, 38.22 ng/μL), followed by the lower stretch (C1: 460 mL, 14.00 ng/μL; C3: 400 mL, 11.00 ng/μL). Sample replicates with filtration volumes below 400 mL (A5, B4, B5, C4, C5) failed to yield detectable DNA, likely due to insufficient water filtration. Despite optimal filtration volumes (>400 mL), A1 (420 mL, 7.66 ng/μL) and C2 (450 mL, 9.10 ng/μL) exhibited low DNA concentrations, suggesting hydrological influences that resulted in localized accumulation or dilution of genetic material. Replicate B3 from Station B (400 mL, 19.50 ng/μL) recorded higher DNA compared to replicate C1 and C3 as this area has a moderate and consistent water flow which likely enhanced the dispersal of eDNA throughout the water column. Gel electrophoresis confirmed high molecular weight DNA in samples exceeding 400 mL, particularly in B1 and B2 which displayed the brightest bands. Statistical analysis (Spearman's ρ = 0.809, p = 0.005) revealed a strong positive correlation between filtration volume and eDNA yield. In conclusion, optimizing filtration volume and accounting for hydrological conditions are crucial for effective eDNA sampling, emphasizing the need for standardized protocols to improve biodiversity monitoring in blackwater peat swamp ecosystems.

Co-utilizing tofu whey with food waste digestate enhances techno-economic feasibility of microalgal single-cell protein production.

Abstract—This project presents the design and implementation of an AI-Enhanced Real-Time Turbidity Monitoring System Using Machine Learning, developed to provide a reliable, low- cost, and intelligent solution for water quality assessment. Tur- bidity, which represents the degree of cloudiness in water caused by suspended particles, is a critical indicator of safety and ecological balance. High turbidity levels may indicate microbial contamination, treatment inefficiency, or environmental degra- dation, making accurate monitoring essential for applications ranging from municipal water supply to environmental protection and industrial processing. Traditional turbidity measurement methods are often expensive, laboratory-dependent, and limited in accuracy under dynamic field conditions, creating barriers to continuous and accessible monitoring. The proposed system overcomes these challenges by integrating a low-cost optical sensor with a microcontroller for real-time data acquisition, and a Random Forest machine learning algorithm for intelligent data interpretation. The microcontroller collects turbidity values from the sensor, which are then processed by the machine learning model to classify water quality more accurately than conventional single-sensor approaches. The Random Forest algorithm was chosen for its robustness to noise, ability to model non-linear relationships, and strong performance with multi-dimensional data. A Python-based application serves as the main program, enabling live predictions, result visualization through a user in- terface, and the possibility of extending the system to cloud-based storage for long-term monitoring and analysis. Experimental evaluation demonstrates that the system achieves significantly higher accuracy compared to standard techniques, confirming the role of machine learning in enhancing turbidity assessment. The modular design allows flexibility for future integration of additional parameters such as pH, temperature, and total dissolved solids (TDS). By combining affordable hardware with advanced data analytics, this project delivers a practical, scalable, and intelligent platform for continuous water quality monitoring. Ultimately, the system contributes to public health protection, sustainable water management, and environmental conservation, while also advancing the application of artificial intelligence in real-time environmental sensing. Index Terms—Turbidity sensing, Random Forest, Arduino, real-time monitoring, environmental sensing, water quality, IoT.

Recent consumer perception of a nutritious diet improves demand for functional and safety products such as probiotics. Present research aims to investigate enriching Solanum lycopersicum (tomato) juice, including free and encapsulated probiotic bacteria. Initially, physicochemical attributes of encapsulations were evaluated, and then tomato juice samples, including a control without bacteria, free or encapsulated Lactobacillus plantarum (L. plantarum, T1 and T2), Lactobacillus delbrueckii (L. delbrueckii, T3 and T4), and a mixture (T5 and T6), were prepared over 28 days of shelf life. Several assays were performed, such as pH, lycopene, turbidity, stability, antioxidant, probiotic viability, sensory, and structure. Physicochemical functions of encapsulation illustrated that the results were in the suitable range. The pH of all treatments declined, and free L. plantarum demonstrated a greater effect on reduction. The control and encapsulated L. plantarum samples exhibited the lowest lycopene, ranging from 0.64 to 0.35 μL/mL, while the highest ranged from 0.64 to 0.50 μL/mL during the shelf life. Encapsulated dual bacteria indicated higher turbidity, stability, and antioxidant features compared to the control throughout shelf life. The control maintained greater transparency than others, and microbial analysis indicated that probiotic populations were elevated until the 14th day and then reduced. The encapsulated dual-bacteria illustrated the maximum viability and sensory, while the control had the minimum ratings. Morphological analysis confirmed a homogeneous structure for encapsulated bacteria. Overall results depicted that treatments containing encapsulated bacteria are considered the preferred option to promote nutritious juice.

Numerous physical, chemical, and biological characteristics of the wastewater of Al-Medan and Danadan estuaries, which drain their Waste water to Tigris River within the city of Mosul. Monthly Water sampling lasted for studied for the period from December 2023 to February 2024. Some physical, chemical and biological characteristics were measured, Temperature, pH, Electrical Conductivity (EC), Total Dissolved Solids (TDS), Dissolved Oxygen (DO), Biochemical oxygen demand (BOD5), Chemical Oxygen Demand (COD), Total Hardness (T.H.), Turbidity, Sulfate (SO2-2), Orthophosphate (PO4-3), Nitrate (NO3-), Chloride (Cl-) and Total Bacterial and Coliform Counts were done. The study showed that some characteristics were exceeded when compared with the Iraqi standards. The results showed an increase in the Biochemical oxygen demand (BOD5) and Chemical Oxygen Demand (COD) with a decrease in Dissolved Oxygen (DO) values. While the temperature and pH were within the normal range at the two sites of the current study and in all months. The study concluded that the quality of the disposed water is unclean with high turbidity, and it is hard to very hard consistency. The values of sulfate ions, orthophosphate, nitrate, and chloride, were within the Iraqi standards for disposal into rivers. In terms of the total numbers of bacteria and coliform bacteria, High numbers were registered in both sites during the study period.

Access to clean water remains a global challenge, particularly in areas where populations rely on surface water. These water sources must be treated. Coagulation with chemicals causes environmental problems and adverse effects on human health. Natural coagulants obtained from papaya (Carica papaya) waste are presented as an alternative that is safe for human health, non-polluting, and biodegradable. The effectiveness of these natural coagulants is compared to that of aluminum sulfate using jar tests and synthetic and natural surface water, with statistical tools to model treatment processes. All coagulants have competitive results, reaching turbidity remotion levels above 90%. However, in equivalent tested ranges, natural coagulants require lower dosages and perform better with high initial water turbidity due to their polymeric bridging mechanisms and adsorption processes through the action of their functional groups, as detected by FTIR analysis. Additional testing with contaminated water from the Valsequillo dam confirms the use of these coagulants to treat water, with papaya seed coagulant yielding the best results and requiring lower doses, making it a competitive alternative. It can be concluded that papaya-based coagulants obtained from waste can be used as an eco-friendly alternative to aluminum sulfate in physicochemical treatments to purify surface water for human consumption.

Rethinking water resources: Harnessing The Gambia River with pressure-driven membrane processes for sustainable supply.

Freshwater microalgae-mediated engineered nanoparticles: Sustainable approach for heavy metals remediation.

Abstract Global climate change and human activities jointly drive the long‐term changes of suspended sediment concentration (SSC) in the ocean, including high turbidity coastal seas such as the semienclosed Bohai Sea. In the past few decades, SSC in the Bohai Sea has exhibited a significant decreasing trend according to satellite observations. In this study, a regional numerical model is employed to carry out sensitivity experiments to quantify the relative contributions of several controlling factors to this multidecadal SSC decline in the Bohai Sea. The model results suggest that reduction in wind speed (by 20% over the past 40 years) can cause the largest decrease (8 mg L −1 , 32%, with values close to satellite remote sensing data) in SSC averaged over the Bohai Sea, associated with a decrease (17%) of wave‐induced bottom shear stress. The coastline and bathymetry changes, due mainly to sediment discharge of the Yellow River, cause large SSC changes at local scales. Since 1976 when the Yellow River mouth was relocated from Bohai Bay to Laizhou Bay, sediment deposition led to significant shoaling in the new estuarine area. This can increase the bottom shear stress by over 50% and the local SSC by more than 30 mg L −1 and an increase (2 mg L −1 , 8%) in SSC over the Bohai Sea. The quantification of contributions from different controlling factors can help to predict long‐term SSC changes in the Bohai Sea, and the method of this study can be applied to other coastal regions where such quantifications are still lacking.

Heavy metal contamination of aquatic ecosystems is a major environmental and public health issue, particularly in rapidly urbanizing regions of developing countries. This study assessed the polymetallic pollution of Lake San-Pedro (Côte d’Ivoire) during the rainy season, focusing on the spatial distribution and severity of contamination. A total of 12 surface water samples—three point samples per station—were collected from four stations selected based on their exposure to industrial, domestic, and urban discharges. Samples were analyzed using inductively coupled plasma mass spectrometry (ICP-MS) to determine the concentrations of nine heavy metals. Key physicochemical parameters were also measured, and the Heavy Metal Pollution Index (HPI) was applied to quantify the overall contamination level. The results revealed elevated concentrations of iron (1.10-1.93 mg/L), aluminum (0.36-1.33 mg/L), and nickel (0.03-0.38 mg/L), all significantly exceeding World Health Organization (WHO) guidelines. HPI values at all stations were well above the critical threshold of 100, indicating severe heavy metal pollution. High turbidity and elevated organic loads were observed across several sites, suggesting substantial degradation of water quality. Statistical analysis (one-way ANOVA) confirmed significant spatial differences (p < 0.05) in the concentrations of Al, Fe, Ni, Pb, and Cr, with stations 1 and 2—located near major anthropogenic activities—showing the highest contamination levels. These findings highlight the urgent need for integrated watershed management measures, including wastewater treatment, pollution source control, and routine monitoring of water quality. This study provides key data to support the protection and sustainable use of Lake San-Pedro’s aquatic resources.

Abstract Deep water, distant sea, unmanned is the inevitable trend of the development of marine engineering, the underwater positioning system for the accuracy, real‐time, and environmental adaptability of the aspects of the increasingly high requirements. The mainstream underwater positioning methods face limitations such as multipath effects, cost, water depth, and water quality, making it difficult to meet diverse needs. This study presents a novel underwater photogrammetry solution based on an active cooperative target that combines optical hardware with intelligent algorithms to achieve millimeter‐level positioning in complex marine environments. Specifically, the system designs and optimizes the hardware configuration, including binocular vision camera, LED array target, and auxiliary optics, through multi‐parameter association to ensure the continuity and stability of positioning. At the algorithmic level, a multilevel image processing module is established through spatiotemporal distribution analysis, expected template matching, physical light intensity modeling, and geometric configuration constraints, which effectively overcomes the dynamic occlusion, scattering degradation and feature extraction errors of cooperative targets. In a standard test cell, the system achieves an angular accuracy of 0.24° and a ranging accuracy of 0.72 mm. A number of positioning systems have been developed to assist in the docking of submarine immersed tube tunnels, and the absolute positioning error is still better than 5 mm even under dynamic high turbidity conditions, which proves its effectiveness.

Abstract Both local and global climate phenomena shape the hydrologic regimes of watersheds. For aridland rivers in the southwestern United States, peak flows occur during two distinct periods: spring snowmelt and summer monsoons. Although discharge (Q) is a primary driver of variation in the production and consumption of instream organic matter, or stream metabolism, few connection have been made regarding how climate impacts ecosystem processes through changes in flow and related disturbances. We considered how variation in disturbance variables, specifically Q and associated changes in turbidity, affected gross primary production during spring snowmelt and summer monsoons in the Rio Grande. Nine years of continuous environmental data (Q, turbidity, light) and climate indices (i.e., El Niño‐Southern Oscillation and Monsoon Index) were used to explain the variation in gross primary production estimates. We found that relationships were sensitive to the timescale of disturbance: at the seasonal scale, high snowmelt Q decreased spring mean gross primary production, while at the daily scale, high turbidity, and to a lesser extent Q, reduced gross primary production during summer. Also, mean Q and turbidity disturbances were uncoupled in spring and inversely related in summer. We conclude that long‐term datasets are essential to uncover emergent relationships between broad‐scale climate patterns and ecosystem processes and are necessary to better understand how hydroclimatic variability drives ecosystem processes at varying time scales in rivers across Earth.

Treated effluent discharge can significantly alter river water quality by affecting parameters such as pH, turbidity, conductivity, and coliform levels, thereby posing risks to both ecosystems and human health. This study evaluated the impact of effluent discharge from the Wupa Wastewater Treatment Plant Abuja, Nigeria on the water quality of the Wupa River. A refined parametric water quality index was developed to enhance monitoring precision, as traditional indices often lack sensitivity to variations in individual parameters. Water samples were collected during the rainy season’s peak mixing period (June–August) from six stations: the influent (INF), effluent (EFF), the point of discharge (POD), upstream of POD (UPOD), and two downstream locations (1kmPOD and 2kmPOD). The samples were analyzed for physical appearance, pH, temperature, conductivity, turbidity, total coliforms, and fecal coliforms. The parametric index incorporated three components: concentration factor, percentage equivalence, and percentage change, to capture parameter-specific changes. Results revealed distinct spatial variations in water quality across the stations. The INF had poor quality, with turbidity between 203–209NTU, total coliforms up to 6000/100 mL, and fecal coliforms also reaching 6000/100 mL, along with a darkish appearance. The EFF showed improvement, with turbidity reduced to 16–19NTU and total coliforms to 400–2000/100 mL, indicating partial treatment success. The UPOD station showed moderate pollution, with turbidity between 69–94 NTU, total coliforms at 600–3000/100 mL, and fecal coliforms ranging from 880–1600/100 mL. At the POD, contamination intensified: turbidity rose to 84–95 NTU, total coliforms increased to 1750–4500/100 mL, and fecal coliforms to 400–900/100 mL. Further downstream, values remained high—turbidity (80–85 NTU), total coliforms (650–3000/100 mL), and fecal coliforms (700–1220/100 mL). pH remained nearly neutral (6.91–7.65), and temperature ranged from 23.8–28.3 °C. Statistical analysis (ANOVA and t-tests) showed significant differences (p < 0.05) in conductivity (245–345 µS/cm), turbidity, and all coliform counts across stations, while differences in pH and temperature were not significant. The parametric index further revealed that treated effluent influenced river quality through elevated turbidity, minor pH variations (+2% in June, −2% to −4% in July and August), and significant increases in coliform levels. Temperature at the POD rose by 5%–12% but declined downstream. Conductivity increased at the POD(+15.5% to +23%) and remained elevated downstream. Turbidity also increased at the POD(+21.7% in June) before declining. Total coliforms surged at the POD(+50% to +191.7%), with residual contamination downstream, while fecal coliforms showed mixed patterns. These findings indicate that although some parameters return to near-background levels within 1 km, microbial contamination persists, raising concerns about waterborne diseases and the safety of downstream water use. The study concludes that the parametric water quality index is effective in assessing site-specific impacts of effluent discharge and underscores the urgent need for improved wastewater treatment and ongoing water quality monitoring to protect public health and environmental integrity.

Sediment-induced lateral circulation in tidal channels with high turbidity: A cross-sectional modeling study

The right to safe drinking water remains a key challenge in developing countries, despite international agreements on Sustainable Development Goal 6 (SDG 6). This research evaluated the quality of groundwater and the associated health impacts in Ahmedpur East, a semi-arid tehsil in the Bahawalpur District, Pakistan, using laboratory analyses, geospatial maps, and hospital health data. The 12 groundwater samples were tested in accordance with the APHA (2017) standards for pH, total dissolved solids (TDS), electrical conductivity (EC), calcium (Ca 2+), magnesium (Mg 2+), potassium (K 2+), and turbidity. Findings revealed that TDS exceeded 1,500 mg/L and EC exceeded 2,000 µS/cm at several locations, indicating high turbidity (&gt;10 NTU) and microbial contamination in low-income areas. In contrast, high hardness was associated with a higher incidence of kidney stones. The conceptual framework combines the water health nexus model and the environmental determinism theory, in which the influence of physicochemical water degradation determines the direct effect on disease spatial patterns. The results are consistent with the theoretical premises of environmental exposure as a cause of disease prevalence in population health. GIS overlays revealed a high degree of spatial convergence between contamination hotspots and disease clusters, indicating that groundwater quality deterioration is a key determinant of local health outcomes. This paper highlights the importance of community-based water treatment, round-the-clock surveillance, and geospatial surveillance as indicators of achieving water security.

Comparative study on the performance of typical coagulation-sedimentation and contact flocculation technology in treating high turbidity mine water

Today, the abundant use of cellulose industry products has led to an increase in production and, as a result, an increase in the volume of water consumed by this industry. On the other hand, the high volumetric flow rate of produced wastewater, chemical oxygen demand (COD), suspended solids and high turbidity of these wastewaters have caused many problems. In recent years, various methods, including physical, chemical and biological, have been used for wastewater treatment. In this study, firstly, the efficiency of the activated sludge collected from cellulose wastewater was investigated in freely suspended cell system in shake flask experiments at 150 rpm and 30 °C. Afterward, to investigate the performance of immobilized sludge, alginate and hybrid alginate-polyvinyl alcohol polymers were used for microbeads production. In this survey, the electrospray technique and response surface methodology (RSM) were employed to produce microbeads and statistical optimization, respectively. In order to optimize the bioremediation process, three variables including electrospray voltage (0–12 kV), the volume of cell-polymer suspension (1–3 mL), and two type of carriers were selected. In order to analyze the wastewater, the results related to COD were evaluated. The optimization results showed that the maximum biodegradation and COD removal of 74% (from 6715 to 1736 mg/L) after 4 days was observed by the alginate-immobilized cells produced with the voltage and polymer-cell solution volume of 3 kV and 2.5 mL, respectively.

This study aimed to identify bacterial isolates associated with mortality events in Salmo trutta rearing farms in Spain and to assess their antibiotic resistance profiles. The analysis covered five fish farms: two with a recent history of antibiotic use and three without any antibiotic application in the six months prior to sampling. Tissue samples were collected from moribund fish displaying clinical signs such as erratic swimming, ocular hemorrhages, fin hemorrhages, and skin lesions during disease outbreaks in 2022 and 2023. The samples were analyzed using real-time PCR, amplification and sequencing of the 16S rRNA gene and the ITS-1 intergenic spacer, and MALDI-TOF mass spectrometry. A total of 19 bacterial isolates were identified, with Gram-negative bacteria, particularly Aeromonas spp., being the most prevalent. Other identified taxa included Plesiomonas sp., Hafnia alvei, Pseudomonas fulva, and Kluyvera intermedia, as well as Gram-positive species such as Carnobacterium maltaromaticum, Lactococcus sp., and Enterococcus faecium. Notably, resistant strains were found in four of the five farms, even in those that had not administered antibiotics, suggesting that environmental contamination and anthropogenic factors may significantly contribute to the spread of resistance. Environmental stressors-such as sudden increases in water temperature and high turbidity caused by suspended organic matter-appeared to precede mortality peaks. The findings highlight the role of Aeromonas spp. as a key bacteria associated with mortality events in S. trutta and underscore the multifactorial nature of antibiotic resistance in aquaculture. No florfenicol-resistant isolates were detected in the farms where it is routinely used, indicating that florfenicol remains an effective antibiotic in aquaculture. However, the continuous and systematic monitoring of its use remains essential. The detection of bacteria not traditionally associated with fish pathology in samples from diseased animals suggests the need for further studies into their pathogenic potential. Overall, this descriptive study emphasizes the importance of preventive health strategies, prudent antibiotic use, and environmental monitoring to mitigate bacterial diseases and limit the spread of antimicrobial resistance in brown trout farming. These findings align with a One Health perspective, linking aquaculture practices, ecosystem integrity, and public health.

Peat water is characterized by high acidity, turbidity, and poor sensory qualities, which limit its usability. This study evaluated the effectiveness of thermally activated coffee waste adsorbent (CWA) for peat water treatment. CWA was prepared by heating coffee waste at 250°C, followed by washing and drying at 60°C. Batch adsorption experiments were conducted using 1–3 g of CWA in 200 mL of peat water at 30°C, stirred at 150 rpm for 30 minutes. The results revealed significant improvements in water quality: pH increased from 3.85 to 4.62; turbidity was reduced by 99.37% (from 75 to 0.47 NTU); conductivity decreased by 30.7% (from 424 to 294 μS/cm); and total dissolved solids (TDS) dropped by 93.3% (from 208 to 14 ppm). The Langmuir isotherm model (R² = 0.7297) provided a better fit than the Freundlich model (R² = 0.5845), indicating monolayer adsorption behavior with a maximum capacity of 0.1634 mg/g and a favorable separation factor (RL = 0.0057). Sensory evaluation confirmed enhanced color and odor. These findings support the use of CWA as a sustainable and low-cost adsorbent for improving peat water quality.

Objective: The aim of this study is to perform the mathematical simulation of a vertical hydraulic flocculator designed for the Vista Bella water treatment plant in Morelia, Michoacán, with the goal of replacing the mechanical flocculation system. Theoretical Framework: Conventional surface raw water treatment is suitable for waters with high turbidity. This process involves several stages such as coagulation, flocculation, sedimentation, filtration, and disinfection, for subsequent distribution to the population. Flocculation is the mechanism by which suspended solids aggregate to form flocs, and these larger and heavier particles can be sedimented. Method: The methodology adopted for this research included developing and analyzing the model and performing numerical simulation to validate the analytical results obtained in the design of a vertical hydraulic flocculator. Results and Discussion: The results demonstrate the feasibility of constructing the hydraulic flocculator to replace the current mechanical system, which involves high operational and energy costs at the plant. Implications of the research: The findings of this study are important for the development of hydraulic flocculators in water treatment facilities, both for designing new units and for adjusting existing ones, given the limited available information on the subject. Originality/Value: This study presents a methodology for flow analysis in hydraulic flocculator tanks to facilitate the transition from mechanical to hydraulic flocculators, reducing the environmental impact caused by motor energy consumption.