Impact Water Quality Research Articles

Estimate the Concentrations of Some Heavy Metals in Industrial Wastewater in Al-Dora Oil Refinery

Industrial wastewater is discharged in large quantities into water bodies, and different treatment processes are employed to reduce pollutant levels. This study quantifies copper, iron, cadmium, cobalt, lead, and nickel levels in industrial wastewater samples at Al-Dora refinery. Results showed variations before and after treatment, with physical and chemical tests conducted in summer and winter. The measured values ​​were (pH, T, Turbidity, EC, TSS, TDS ), respectively (8.23, 34.8 °C, 60.88 NTU, 2883 ms/cm, 575 mg/L, 1441 mg/L) in summer, while in the winter it was (7.516, 28.6 °C, 100.6 NTU, 1147 ms/cm, 780 mg/L, 569.8 mg/L), respectively. Heavy metals were measured and showed a slight decrease during the treatment units, nevertheless, they continue to be among the environmental determinants of the Iraqi river maintenance system (1967). The measured elements were (Cu, Fe, Cd, Co, Pb, and Ni), and their concentrations in the treated water and discharged to the river were (0.064, 0.020, 0.109, 0.031, 0.029, 0.092) mg/L, respectively, in the winter. While in summer, their concentrations were (0.017, 0.018, 0.0105, 0.017, 0.138, 0.078) mg/L, respectively. The values of pollutant concentrations were a key environmental factor in the maintenance of Iraqi rivers, as the treatment plant effectively reduced or removed these pollutants from the water before discharging it into the river, without impacting water quality.

Assessing the water quality impact of floating treatment wetlands strategically placed in two stormwater retention ponds.

Assessing the water quality impact of floating treatment wetlands strategically placed in two stormwater retention ponds.

Predicting Post-Wildfire Stream Temperature and Turbidity: A Machine Learning Approach in Western U.S. Watersheds

Wildfires significantly impact water quality in the Western United States, posing challenges for water resource management. However, limited research quantifies post-wildfire stream temperature and turbidity changes across diverse climatic zones. This study addresses this gap by using Random Forest (RF) and Support Vector Regression (SVR) models to predict post-wildfire stream temperature and turbidity based on climate, streamflow, and fire data from the Clackamas and Russian River Watersheds. We selected Random Forest (RF) and Support Vector Regression (SVR) because they handle non-linear, high-dimensional data, balance accuracy with efficiency, and capture complex post-wildfire stream temperature and turbidity dynamics with minimal assumptions. The primary objectives were to evaluate model performance, conduct sensitivity analyses, and project mid-21st century water quality changes under Representative Concentration Pathway (RCP) 4.5 and 8.5 scenarios. Sensitivity analyses indicated that 7-day maximum air temperature and discharge were the most influential predictors. Results show that RF outperformed SVR, achieving an R2 of 0.98 and root mean square error of 0.88 °C for stream temperature predictions. Post-wildfire turbidity increased up to 70 NTU during storm events in highly burned subwatersheds. Under RCP 8.5, stream temperatures are projected to rise by 2.2 °C by 2050. RF’s ensemble approach captured non-linear relationships effectively, while SVR excelled in high-dimensional datasets but struggled with temporal variability. These findings underscore the importance of using machine learning for understanding complex post-fire hydrology. We recommend adaptive reservoir operations and targeted riparian restoration to mitigate warming trends. This research highlights machine learning’s utility for predicting post-wildfire impacts and informing climate-resilient water management strategies.

Quantifying the Water Quality Impacts of Cropland Farming in China: A Satellite Data Approach

AbstractWe compile a unique satellite‐derived panel dataset to investigate the impacts of cropland coverage on the outbreak of Harmful Algal Blooms (HABs) in China between 2003 and 2019. Our results indicate that a 1% increase in cropland leads to a 0.5% increase in the size of HABs in lakes larger than 20 km2. The increase in cropland not only affects the size of HABs but also significantly prolongs their duration on average. Furthermore, we provide evidence of a diminishing legacy effect of cropland on HAB area over time and a nonlinear relationship between cropland area and HABs. Fertilizer leakage from cropland shapes the entire pollution mechanism, with farming practices that require elevated fertilizer posing significantly greater impacts on water quality. While the nationwide fertilizer reduction policy implemented in 2015 successfully dampens HABs in nonreservoir lakes during the initial three years, its long‐term effects remain uncertain. This study highlights the potential of satellite imagery data for economic analyses of nutrient pollution in China.

Impact of Land Use Change on Lake Pollution Dynamics: A Case Study of Sapanca Lake, Turkey

Modeling non-point source pollution dynamics in inland lake basins is essential for safeguarding water quality, maintaining ecosystem integrity, protecting public health, and advancing long-term environmental sustainability. This study explores non-point pollution dynamics in the Sapanca Lake basin, Turkey, in association with the basin’s land use, land cover, hydrology, pollutant sources, and water quality parameters. The required data were gathered via a three-year monitoring program, which was carried out at 12 sampling stations around the lake, as well as using the collecting field measurements and GIS databases. Stepwise multiple regression analysis was employed to determine the best relation between non-point pollutants and land features. The results showed that urbanization and population density have significant correlations with the total nitrogen (TN) and total phosphorus (TP) in the study areas. Rivers crossing pristine areas, such as forests and uncultivated lands, demonstrated better water quality, thereby positively contributing to the lake ecosystem conservation. The highest nutrient loads were observed in streams that flow through highly urbanized sub-basins, followed by predominantly agricultural areas. This is likely due to runoff from urban environments, leaching from cultivated land, and contributions from livestock and tourism facilities. Conversely, densely forested regions exhibited the lowest levels of nutrient loads, highlighting their capacity for nutrient retention. The peak levels of non-point source pollution (TN = 5.22 mg/L and TP = 0.53 mg/L) were recorded in catchments with the highest degree of urbanization, whereas the lowest values (TN = 0.28 mg/L and TP = 0.04 mg/L) were found in the least urbanized areas. These findings emphasize that nutrients primarily impact water quality because of increasing urban and agricultural activities, while forested land plays a vital role in preserving lake water quality. To ensure sustainable water quality in lake basins, it is essential to strike a careful balance between protective measures and utilization policies, prioritizing conservation efforts.

Optical properties and photobleaching of wildfire ashes aqueous extracts.

Wildfires can severely degrade soils and watersheds. Post-fire rain events can leach ashes and altered dissolved organic matter (DOM) into streams, impacting water quality and carbon biogeochemistry. The photochemical properties and persistence of DOM from wildfire ash leachates are not well understood. To establish a range of properties, wildfire DOM leachates were generated from (i) surficial [grey and black] wildfire ashes, (ii) mineral soils below ash, and (iii) unimpacted soils from two Colorado wildfire scars. Subsequently, the leachates were studied under simulated sunlight. Photochemical properties of absorbance, fluorescence and 1O2 quantum yield (ΦF and Φ1O2) were determined for thirteen wildfire leachates. Φ1O2 of ash leachates was greatest (7.6 ± 3.4%), followed by underlying mineralized soil leachates (4.6 ± 0.7%), and control soil leachates (Φ1O2 = 3.9 ± 1%). Correlations between increasing E2 : E3, ΦF, Φ1O2 suggest that surface ash leachates with elevated molar absorptivity may play an important role in 1O2 production that is not well documented. Interestingly, photobleaching experiments comparing ash DOM to unimpacted soil DOM revealed ash leachates lost fluorescence, absorbance, while producing CO2 at rates ∼3 fold greater than soils. This suggests that aromatic features of ashes may cause degradation of wildfire DOM faster than unimpacted DOM in the environment.

Active biomonitoring of river pollution using an ex-situ exposure system with two model species.

In the context of increasing pollution pressure on aquatic ecosystems, it is essential to improve our knowledge of habitat quality and its suitability for organisms. It is particularly relevant to better integrate early life stages of fish into pollution biomonitoring programs, as they are reliable indicators of ecosystem integrity and because of their high sensitivity to pollutants. To avoid the influence of environmental parameters on their development, a lab-on-field approach, called the ex-situ exposure method, was developed. Aquatic organisms were exposed to a continuous flux of water under semi-controlled temperature, oxygen, and photoperiod conditions to avoid the influence of these confounding factors when interpreting the results. To investigate the potential role of water contamination, this active biomonitoring method was applied to the Garonne River (Southwest France), where migratory fish populations have declined. Two model species from different taxa were used: embryos of the Japanese medaka (Oryzias latipes) and adults of the crustacean Gammarus fossarum. The results showed a significant impact of water quality on embryo mortality and early hatching in two separate experiments on Japanese medaka. In addition, an induction of feeding rate was observed in exposed gammarids, but no impact on their embryo survival, suggesting differences in sensitivity between the two species selected. Chemical and biological analyses did not identify trace metals, pesticides, or microorganisms as potential sources of toxicity in medaka embryos or G. fossarum. These results raise concerns about the quality of the water in the Garonne River and its toxicity to aquatic organisms.

PRODUCTIVITY OF WHITE SHRIMP (Litopenaeus vannamei) WITH THE ADDITION OF PROBIOTICS AND PREBIOTICS

Vaname shrimp remains a prime commodity due to several advantages, including the ability to thrive in a salinity range of 0.5-31 ppt, with a stocking density of 100-300 individuals/m², a faster growth cycle of 90-100 days, and a high appetite leading to rapid growth. Currently, the technology for culturing vaname shrimp has advanced with the implementation of intensive systems that utilize high stocking densities, although this impacts water quality. One approach to maintaining good water quality, especially in reducing organic waste, is the use of prebiotics and probiotics. Further studies are needed to determine the productivity of vaname shrimp with the addition of probiotics and prebiotics in shrimp culture. This research employed a survey method with parameters observed including productivity and water quality. Productivity encompassed stocking density, Average Body Weight (ABW), Average Daily Growth (ADG), population, biomass, Food Conversion Rate (FCR), Survival Rate (SR), and size. Water quality parameters measured included salinity, temperature, pH, DO using a Multitester, alkalinity, TOM, Ca, Mg, Total Hardness using titration, PO4, NH4, NO3, NO2 using a test kit, the number of green algae, blue-green algae, diatoms, euglena, and dinoflagellates using a hemocytometer, zooplankton, and protozoa using a Sedgewick Rafter, total bacteria, total vibrio, and the number of yellow, green, and black vibrio using Total Plate Count (TPC). Data analysis used descriptive methods. The results showed that the harvest exceeded the company's target, and the SR and FCR values were categorized as good in vaname shrimp cultivation. Water quality measurements indicated that conditions were still optimal for vaname shrimp culture.

Assessing water quality and land use impact in the Itanhém River basin: a study between the cities of Teixeira de Freitas and Alcobaça, Bahia

ABSTRACT Land use and occupation play a crucial role in shaping the physical and chemical properties of water. Like this study aimed to analyze the water quality parameters of a stretch the Itanhém River and relate this quality with the land use and occupation . To this end, samples were collected from seven strategically chosen points,identifying the physical-chemical variables necessary to obtain the Water Quality Index (WQI), . The Florestal Forum database was applied to analyze land use. The results showed that the body of water studied obtained values of thermotolerant coliforms and total phosphorus higher than the maximum values, WQI values that ranged between bad and good, and the Trophic State Index (TSI), it was identified as hypereutrophic was characterized the presence of pastures (both dirty and clean). Therefore, adequate management of water resources at the local level is necessary, as are agricultural, forestry, and sanitation activities.

A SWAT model depicts the impact of land use change on hydrology, nutrient, and sediment loads in a Lake Michigan watershed

High levels of nutrient loads in a catchment indicate the presence of pollution sources that must be identified and quantified. These loads in surface and groundwater have been a major concern that impacts water quality in the Midwestern US, including the Great Lakes Basin. In this study, we use the Soil and Water Assessment Tool (SWAT) to assess the impact of land use changes on hydrology, nutrients, and sediment loads for the St. Joseph River Basin (SJRB), which drains an area of 12,200 km2 in Southwest Michigan/Northwest Indiana and is a primary source of pollutant to Lake Michigan. The SWAT models were developed to simulate streamflow, baseflow, total suspended solids (TSS), total phosphorous (TP), dissolved reactive phosphate (DRP), total nitrogen (TN), and nitrate (NO3-N), using data from two stream gauges. The calibrated models accurately simulated the studied variables across the SJRB. The simulated average annual baseflow for Niles and Paw Paw subwatersheds were 153 and 190 mm, respectively. The impacts of land use change on variables from the SJRB were also explored. The impact of land use change on water quality over time was statistically significant but trends were not linear. Hydrology, sediments and nutrients were also quantified at the subbasin level. Subbasins with heavy urbanization or agricultural drainage infrastructure, showed more substantial increases in sediment and nutrient loads as well as decreased groundwater recharge. This study will aid in the evaluation of historical and future water resources for Midwestern rivers, enabling stakeholders to prepare for future impacts, and to execute conservation and management to sustain the SJRB.

Оценка воздействия стока некоторых рек Сочинского Причерноморья на прибрежную морскую среду в зонах их плюмов

The paper assesses the impact of water quality of some rivers located within the Black Sea coastal zone in the Sochi area on the ecological security and status of the Black Sea coastal line. The relevance of the study is determined by the lack of a unified methodological approach to establishing parameters for assessing the ecological condition of water bodies within the Black Sea coastal area. The study is the first to consider a unified river-sea system in the context of integrated monitoring of natural water quality. The research is based on biological methods (biotesting, bioindication) to evaluate the state of biological communities and processes in combination with the analysis of geological aspects. This allows a detailed study of the influence of various factors on the marine environment ecological safety. It was revealed that the marine environment has the highest levels of toxicity in the inflow zones of small rivers, which are subject to significant complex impacts from municipal solid waste landfills and industrial enterprises located in their catchment areas. In the marine plumes of rivers classified as medium, which are important for water management, recreation and fisheries in the region, seawater has a lower toxic effect as a result of significant dilution. Thus, small rivers inflows can cause similar negative impacts on the quality of the marine environment and the status of coastal biocenoses as runoff from larger watercourses. The study results can contribute to the development of new approaches for the assessment and monitoring of the environmental security of the coastal marine environment, based on the concept of the ecological system integrity in the context of interdependencies associated with the pollutants and nutrients transfer between qualitatively different environments and associated with them river and cjastal marine hydrobiocenoses.

A laboratory-scale simulation framework for analysing wildfire hydrologic and water quality effects

Background Wildfires can significantly impact water quality and supply. However logistical difficulties and high variability in in situ data collection have limited previous analyses. Aims We simulated wildfire and rainfall effects at varying terrain slopes in a controlled setting to isolate driver-response relationships. Methods Custom-designed laboratory-scale burn and rainfall simulators were applied to 154 soil samples, measuring subsequent runoff and constituent responses. Simulated conditions included low, moderate, and high burn intensities (~100–600°C); 10-, 200-, and 1000-year storm events (~14–51 mm/h); and 10–29° terrain slopes. Key results Simulators can control key drivers, with burn intensities highly correlated (R2 = 0.64) with heat treatment durations. Increasing burn intensity treatments generally saw significant (α = 0.05) increases in responses, with runoff and sedimentation increasing by ~30–70% with each intensity increment. Carbon and nitrogen peaked at moderate intensities (~250°C), however, with concentrations ~200–250% of unburned samples. Conclusions Distinct responses at each burn intensity indicate nuanced changes in soil physical and chemical composition with increased heating, exacerbating driving mechanisms of runoff and sedimentation while reducing carbon and nitrogen through volatilisation. Implications This work furthers our understanding of interactions between complex geographic features and the mosaic of burn intensities which exist in wildfire-affected landscapes.

A Case of One Step Forward and Two Steps Back? An Examination of Herbicide-Resistant Weed Management Using a Simple Agroecosystem Dynamics Model

Global herbicide-resistant weed populations continue rising due to selection pressures exerted by herbicides. Despite this, herbicides continue to be farmers’ preferred weed-control method due to cost and efficiency relative to physical or biological methods. However, weeds developing resistance to herbicides not only challenges crop production but also threatens ecosystem services by disrupting biodiversity, reducing soil health, and impacting water quality. Our objective was to develop a simulation model that captures the feedback between weed population dynamics, agricultural management, profitability, and farmer decision-making processes that interact in unique ways to reinforce herbicide resistance in weeds. After calibration to observed data and evaluation by subject matter experts, we tested alternative agronomic, mechanical, or intensive management strategies to evaluate their impact on weed population dynamics. Results indicated that standalone practices enhanced farm profitability in the short term but lead to substantial adverse ecological outcomes in the long term, indicated by elevated herbicide resistance (e.g., harm to non-target species, disrupting natural ecosystem functions). The most management-intensive test yielded the greatest weed control and farm profit, albeit with elevated residual resistant seed bank levels. We discuss these findings in both developed and developing-nation contexts. Future work requires greater connectivity of farm management and genetic-resistance models that currently remain disconnected mechanistically.

Assessing Changes in China's Pond Water Quality From 1989 to 2020: Implications for Green Development in Aquaculture

ABSTRACTSince 1989, China has become the world's largest aquaculture producer through pond culture, significantly contributing to global food security but potentially posing environmental threats. However, little is known about the changes in the pond water quality at broad spatial and temporal scales, thus creating challenges in the sustainability of pond aquaculture. Herein, we explore changes in water quality in China's aquaculture ponds from 1989 to 2020 and assess the waterbody's health status to optimize sustainable management strategies. This study highlights pond water quality changes closely associated with China's aquaculture practices, development, and related policies. Seasonal and regional farming variations significantly impact water quality, with peak aquaculture seasons and Central China and North China associated with the lowest water quality scores. Pond water quality initially declined with the rise of intensive aquaculture but improved after 2012 with the adoption of ecological engineering measures, eco‐farming practices, and policies supporting green development. Under a scenario combining these efforts, the water quality score in 2035 is projected to increase by 57% of the 2020 level. These findings reveal that national ecological initiatives and advancements in green aquaculture techniques and public policies can significantly enhance the water quality of China's aquaculture ponds, offering valuable insights into environmental governance in global agriculture.

Remote sensing of cyanobacterias with Sentinel-2 in the Salto Grande

Abstract. The Salto Grande Reservoir of the Uruguay River experiences recurrent increases of cyanobacteria bloom, which negatively impacts water quality, with adverse consequences for public health and tourism. This study uses images from the Sentinel-2 satellite to investigate different methods for detecting and monitoring cyanobacteria. Two indices are calculated and two models are applied for the detection of cyanobacteria: the Normalized Difference Vegetation Index (NDVI), the Normalized Difference Water Index (NDWI) and Chlorophyll-a models M1 and M2, which have not previously been evaluated with images from Sentinel-2. NDVI is commonly used to identify areas with vegetation cover. The NDWI, using green and near-infrared (NIR) bands, is used as a filter for the application of Chlorophyl-A models since it is very useful for the identification of aquatic areas. Both M1 and M2 estimate the concentration of chlorophyll in the water, with model M2 demonstrating greater efficiency in the detection of cyanobacteria compared to model M1. Sentinel-2 images allow the correct observation of variations in the concentration of cyanobacteria in the riverbed, facilitating the monitoring of seasonal changes and cyanobacteria blooms. The results of our investigation underlines the effectiveness of NDWI when used with the Sentinel-2 images for identifying surface water areas and the M2-Chlorophyll-a model for detecting cyanobacteria in them. Combining these indices with on-site measurements is likely to offer a robust approach to monitoring and managing of the Salto Grande Reservoir.

The impact of feed type and water quality on the edible viscera and dressing percentage of male and female Ross 308 broiler chickens

During the period of October 20, 2023, to November 25, 2023, a study was conducted in a local field in Nasiriya District/ Dhi Qar Governorate to ascertain how the kind of diet and the water quality affect the dressing percentage and the relative weights of the edible internal organs (heart, liver, and gizzard). In broiler chickens, both male and female. The following six treatments, each consisting of three replicates, were randomly assigned to 300 sexed one-day-old chicks, with an average weight of 40 grams, for a period of 35 days: Drinking tap water and using mash feed for control constitute the first therapy. Providing drinking water (tap water) and pellet feed (control) is the second treatment. The third treatment involves giving out magnetized drinking water and mash meal. Providing magnetized drinking water and pellet feed is the fourth treatment. Providing drinking water (RO) and mash feed is the fifth treatment. The sixth treatment is providing pellet feed and drinking water (RO). The treatment of RO water and magnetized water was superior in the percentage of filtration and the relative weight of the heart, liver, and gizzard over the liquefaction water treatment, as demonstrated by the findings, which indicated a substantial superiority (p0.05) for the quality of drinking water. Regarding fodder, the findings indicated a noteworthy rise in the heart's relative weight, but had no impact on the liver's or gizzards relative weight or the clearance rate.

Disposable diaper consumption and waste in urban Ghana and Kenya: The role of manufacturing, distribution, and branding

Studies have reported widespread disposable diaper (DD) consumption in parts of urban Africa, increasing municipal waste generation and with mismanaged DD waste impacting water quality. However, the DD manufacturing and distribution systems behind this trend are little studied, yet understanding these underlying systems is critical in informing efforts to promote extended producer responsibility. This study therefore aims to assess DD brand preferences and trends in international trade in absorbent hygiene products in two case study Sub-Saharan countries. A cross-sectional survey was undertaken of 440 carers of children aged 0–36 months attending health facilities in Greater Accra, Ghana and Kisumu, Kenya. Survey analysis was supplemented by analysis of international trade in absorbent hygiene products for both countries from 2000–2021. Trade data showed DD imports to Ghana and Kenya increased from 2000–17 particularly from China, but declined thereafter. This coincided with Chinese foreign direct investment establishing DD production facilities within both countries in 2018–19, and increased DD exports from Kenya and Ghana to surrounding countries. Meanwhile, 93.0% and 94.2% of survey respondents in Greater Accra and Kisumu respectively reported using DD. In Greater Accra and Kisumu respectively, 62.4% and 45.3% of survey participants reported using the brand produced by these new domestic manufacturing facilities, with 29.8% and 40.9% using imported brands. In Greater Accra, approximately half of reported imported brands were unregistered with the regulator. Given its market dominance, we therefore recommend engagement with the leading manufacturer to identify product or waste management innovations to address water pollution from DD waste. We also recommend similar engagement with imported brand manufacturers and greater DD import regulation in Ghana, given lack of imported brand registration.

Impact of Water Quality on Density of Birds in Bahr Najaf Depression, Iraq.

Impact of Water Quality on Density of Birds in Bahr Najaf Depression, Iraq.

Impact of water residence time and stratification on water quality improvement of an artificial brackish waterway

Study regionThe Ara Waterway, an artificial inland brackish waterway in South Korea. Study focusThis study investigates how water residence time and stratification affect water quality in an artificial brackish water system, which has different characteristics from natural environments and is under-researched, using numerical simulations. Various hydrodynamic conditions, including freshwater discharge and travel distances, were analyzed to understand their impact on residence times and stratification, offering insights for optimizing water quality management. New hydrological insights for the regionThis study demonstrates that stratification significantly impacts water quality more than residence time in artificial brackish waterways. In contrast to lakes or reservoirs, increasing freshwater discharge in artificial brackish waterways can enhance stratification, reducing vertical mixing and degrading water quality, especially in the bottom layers. In the F0 scenario, excluding freshwater inflow increased summer maximum dissolved oxygen by 1.37 times compared to the validation case. This suggests that breaking stratification, such as through underwater aeration systems, may be more effective than focusing on residence time. In the L15 scenario, with the longest travel distance, upstream total nitrogen and total phosphorus increased by 18.37 % and 26.12 %, while downstream levels decreased by 3.35 % and 10.52 %. Additionally, poorer quality freshwater can degrade overall water quality, even with shorter residence times. These findings emphasize the need for careful management of inflowing water to maintain water quality in artificial brackish waterways.

Improving Seasonal Distribution Estimation of Total Suspended Solids in The Madura Strait Waters, Indonesia

High TSS causes siltation around coastal areas in the Madura Strait. TSS impacts water quality and habitat health. It's necessary to know that TSS distribution can vary each season. The algorithm detects TSS distribution by processing Landsat-8 satellite image data. However, existing algorithms are sometimes only suitable for some instances, so the results do not correspond to actual conditions. Therefore, this paper wants to build a better detection model using Laili's algorithm to determine whether satellite image analysis can explain the exact conditions. Laili's algorithm detection was validated and corrected against field data via a correlation test. It’s necessary to know the spatial distribution pattern of data attribute values using the Moran Index. The results TSS in the dry season is 5-18 mg/L and covers an area of up to 4 km; in the rainy season, it is 5-22 mg/L and can cover an area of up to 7.8 km. Moran's Index results show that spatial autocorrelation in the distribution pattern results in a cluster pattern. These results show that the detection model is relatively reasonable and can be used as training data to detect the distribution of TSS in the Madura Strait in subsequent years.