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We initiated a collaboration between local government, academia, and citizen scientists to investigate high frequencies of elevated Escherichia coli bacteria levels in the coastal Short Beach neighborhood of Branford, Connecticut. Citizen scientist involvement enabled collection of short-duration postprecipitation outfall flow water samples (mean E. coli level = 4930 most probable number per 100 mL) and yielded insights into scientific collaboration with local residents. A records review and sanitary questionnaire identified aging properties with septic systems (3.3%) and holding tanks (0.6%) as potential sources of the E. coli contamination. (Am J Public Health. 2022;112(9):1261–1264. https://doi.org/10.2105/AJPH.2022.306943 )

Developing countries have increased sanitation investment to reduce diarrheal diseases. However, the direct health benefits of latrine construction can be offset by water pollution externalities due to poor treatment of fecal sludge. I estimate these negative externalities of a sanitation policy in India that subsidized the construction of over 100 million latrines. Exploiting geographical variation in soil characteristics and the differential increase in latrine coverage across districts, I find that the policy increases river pollution by 72%. While it reduces diarrheal mortality overall, this positive health effect is two-thirds smaller in areas with lower capacities for treatment of fecal sludge where water pollution externalities are consequently larger.

Plastics products are becoming more popular because of their cheap production cost, highflexibility, and convenience to use. These products end up in the environment as wastes when, they are not recycled or managed properly. As a result, natural energy sources, such as sunlight, can degrade them and generate secondary micro and nanoscale plastics. While there are research, findings of the fate and transport of nanoplastics using model nanospheres, research on fate of, heterogeneous secondary nanoscale plastics that closely resemble the nanoplastics in nature is, limited. Moreover, polypropylene (PP) is one of the most widely used plastic types with a low, specific gravity. However, fate and transport of polypropylene secondary nanoscale plastics are, still unexplored. The first objective of this research is to characterize the polypropylene, secondary nanoscale plastics by measuring their hydrodynamic diameter and surface charge by, varying different parameters such as pH, ionic strengths, salt types, and natural organic matter, (NOM) concentrations. The results show that the surface charge of polypropylene secondary, nanoscale plastics increases with pH. The critical coagulation concentration (CCC) was also, determined in the presence and absence of NOM. Results show that the CCC values of PP, secondary nanoscale plastics for NaCl, MgCl2, and CaCl2 are 500 mM, 35 mM, and 20 mM, respectively, higher than the CCC values of polyethylene (80 mM NaCl, 3 mM MgCl2, 0.1 mM, CaCl2) and polystyrene (800 mM NaCl, 25 mM MgCl2, 10 mM CaCl2) nanoplastics. When, NOM is present in water, the adsorbed NOM causes steric repulsion and makes the particles, more stable. The second objective of the research is to investigate the interactions of PP, secondary nanoscale plastics with bare silica and NOM coated surfaces and observe their, deposition and remobilization. Results suggest that PP secondary nanoscale plastics are more, mobile on silica surfaces than NOM coated surfaces. Their deposition and remobilization are, governed by the presence of NOM coated surfaces and divalent cations since they are ubiquitous, in nature. This study indicates that significant transport of PP secondary nanoplastics will be, possible in natural waters, and destabilization of these nanoplastics will be difficult.

The present study involves the chemical and bacteriological analysis of water from different sources i.e., bore, wells, bottle, and tap, from Peshawar, Mardan, Swat and Kohat districts of Khyber Pakhtunkhwa (KP) province, Pakistan. From each district, 50 water samples (10 samples from each source), regardless of urban and rural status, were collected from these sources and analysed for sulphates, nitrates, nitrites, chlorides, total soluble solids and coliforms (E. coli). Results indicated that majority of the water sources had unacceptable E. coli count i.e.> 34 CFU/100mL. E. coli positive samples were high in Mardan District, followed by Kohat, Swat and Peshawar district. Besides this, the some water sources were also chemically contaminated by different inorganic fertilizers (nitrates/nitrites of sodium, potassium) but under safe levels whereas agricultural and industrial wastes (chloride and sulphate compounds) were in unsafe range. Among all districts, the water quality was found comparatively more deteriorated in Kohat and Mardan districts than Peshawar and Swat districts. Such chemically and bacteriologically unfit water sources for drinking and can cause human health problems. Resumo O presente estudo envolve a análise química e bacteriológica de água de diferentes fontes, ou seja, furo, poços, garrafa e torneira, dos distritos de Peshawar, Mardan, Swat e Kohat da província de Khyber Pakhtunkhwa (KP), Paquistão. De cada distrito, 50 amostras de água (10 amostras de cada fonte), independentemente do status urbano e rural, foram coletadas dessas fontes e analisadas para sulfatos, nitratos, nitritos, cloretos, sólidos solúveis totais e coliformes (E. coli). Os resultados indicaram que a maioria das fontes de água tinha uma contagem inaceitável de E. coli, ou seja, > 34 UFC / 100 mL. As amostras positivas para E. coli foram elevadas no distrito de Mardan, seguido por Kohat, Swat e distrito de Peshawar. Além disso, algumas fontes de água também foram contaminadas quimicamente por diferentes fertilizantes inorgânicos (nitratos/nitritos de sódio, potássio), mas em níveis seguros, enquanto os resíduos agrícolas e industriais (compostos de cloreto e sulfato) estavam em níveis inseguros. Entre todos os distritos, a qualidade da água foi considerada comparativamente mais deteriorada nos distritos de Kohat e Mardan do que nos distritos de Peshawar e Swat. Essas fontes de água química e bacteriologicamente impróprias para beber podem causar problemas à saúde humana.

In order to assess the degree of pollution of surface water from Boussalem river from the city of Setif, we conducted during 2014; a study of physical and chemical characteristics of surface water. The results showed that water is loaded into mineral matter in terms of electrical conductivity (Avg = 1059,18 μS/cm ± 631,7), in turbidity (Avg = 15,713 NTU ± 22,19), in TSS (Avg = 189 mg/l ± 119,5), with low dissolved oxygen (Avg = 2,98 mg/l ± 2 ,44). The pH is closed to neutrality (Avg = 7,78 ± 0,74), the temperature is 17°C ± 11,13). Also, one revealed according to the results which water of Bousselam river is bad according to the quality standards of surface water and this is directly related to factors anthropic.

The road is the main gateway to human life and links essential access points. Some structure pavement failures happened due to the base layer's instability. Fly ash has been used in several parts of pavement structures to increase stability. One significant concern with using fly ash in base course stabilization is its proportion and potential impact on water quality standards. This research aimed to evaluate base course stabilization performance using fly ash-based geopolymers, as well as assess their impact on water quality standards. Materials in this study consisted of aggregate, fly ash, water, and alkaline reagent solutions. The variation of mix considered with a variety of alkaline reagents, namely without alkaline reagents, 3 mol, 6 mol, 9 mol, and 12 mol of NaOH. The ratio between NaOH and Na2SiO3 is 1:2. The use of fly ash in the class A aggregate base course layer has not been able to meet specifications. However, by providing 9 mol of alkaline reagent, the strength of the mixture increases so that the CBR value meets the specifications due to geopolymer bonding. When the alkaline reagent solution becomes more concentrated, the optimum water content decreases, and the bond between aggregates strengthens. The effect of alkaline reagents on water quality standards increases the acidity (pH) value, while other parameters such as BOD, COD, and TSS still meet the standards. This research point to another practical approach that is effective in the field to increase the stability of the base course layer and is environmentally friendly.

Purpose: The paper is aimed to compare the current Status of the projects in Pakali and Bharaul water supply and sanitation project in Sunsari district. Design/Methodology/Approach: The effectiveness of the water user supply committee, the project's productivity index, the payback period, and the operating ratio of the chosen projects were analysed. Findings/Result: The functionality status of Pakali and Bharaul water supply projects are found good but need better by increasing by business. The operating ratio of Pakali and Bharaul water supply projects was found 0.8 and 0.72 respectively which means it can bear its operating and maintenance cost. The selected projects are found technically feasible, economically viable. Projects have profitability indices that are more than 1, indicating potential to be implemented. Both water supply projects are water user supply committee registered, having own staff, Operation and maintenance fund, efficient water tariff collection, reliability and accessibility but lack of water user supply committee meeting, record keeping proper in Bharaul compare to Pakali whereas lack of water safety plan in both projects. Originality/Value: The study will be a benchmark for continuous performance improvements of the systems and reference for department for assessing performance of any system of water supply. Paper Type: Status enquiry Research

Climate change may impact human health through the influence of weather on environmental transmission of diarrhea. Previous studies have found that high temperatures and heavy precipitation are associated with increased diarrhea prevalence, but the underlying causal mechanisms have not been tested and validated. We linked measurements of Escherichia coli in source water (n = 1673), stored drinking water (n = 9692), and hand rinses from children

Along with the country's comprehensive strength, the people's wealth is also more and more substantial, in every aspect of life has been significantly improved, people also pay more attention to environmental protection. The harm of environmental pollution should not be underestimated. Once the environmental pollution accident occurs, it must be handled promptly, or a series of consequences are very serious. Therefore, it is necessary to study the Bayesian method of water quality emergency monitoring in the disposal of environmental pollution accidents. The purpose of this article was to solve the slow progress of water quality monitoring in the disposal of environmental pollution accidents. Through the Bayesian method of environmental pollution accident disposal in water quality emergency monitoring, the target node variables, intermediate node variables, and evidence node variables are used for analysis. Construct a Bayesian network topology. This article uses the fuzzy Bayesian network risk assessment model to provide a reference for the emergency monitoring of water quality disposal in regional environmental pollution accidents and conduct risk assessment to facilitate the next work arrangement. The results show that the Bayesian method of water quality emergency monitoring in environmental pollution accident disposal can provide effective feedback. Compared with traditional methods, the risk assessment of water quality monitoring for environmental pollution accidents is 40% faster and 10% more accurate in calculating the probability of accidents caused by basic factors. The application of the Bayesian water quality emergency monitoring method in environmental pollution accident disposal is conducive to improving the efficiency of environmental pollution disposal, in-depth analysis of the existing problems in the current environmental emergency management work, and suggestions for improving the emergency mechanism of sudden environmental pollution accident. The purpose was to provide reference for the government to properly handle sudden environmental pollution accidents.

Indiscriminate discharge of untreated wastes from into the aquatic ecosystem may result in deterioration of water quality, as well as poses a great threat to the balance of aquatic ecosystems and human health. This study investigated the seasonal variation in physicochemical characteristics and assessed the pollution status of Mahin Lagoon and its adjoining creeks using standard method. Results of physico-chemical parameters varied significantly (p

In this study, aquatic macroinvertebrates were used as bioindicators to determine the ecological conditions of the Lapa River, located between the municipalities of Cayey and Salinas, Puerto Rico. The water quality of the river was evaluated through the calculation of the Puerto Rico Biological Monitoring Working Party (BMWP-PR), as well as its degree of contamination using the Puerto Rico Family Biotic Index (FBI-PR). Bimonthly sampling was conducted across four sampling sites for a period of 12 months. The sampling sites were positioned upstream and downstream within the nature reserve, and outside and downstream its borders. The BMWP-PR results showed that the site upstream-inside the nature reserve had good water quality, and the site downstream-inside the nature reserve had regular water quality, showing some areas with eutrophication. The water quality outside-downstream from the nature reserve was poor. The FBI-PR results showed that there was mild organic contamination inside the nature reserve, while there was substantial organic contamination in the site that was outside-downstream from the nature reserve. We concluded that the section of the river located within the nature reserve had better ecological conditions than the stretch of the river located outside-downstream of the nature reserve, because it is located within a protected area that has barely been impacted by human activity.

Since 2001, the Indonesian government has formulated and implemented several restoration programs to improve the Citarum’s water quality. However, these programs were often contested, particularly concerning the meanings of ‘water quality’ and how those informed approaches to responsibility and involvement. This paper problematises river restoration in view of these controversies towards improving people’s lives and their environment. Our investigation found (1) a selective use of scientific knowledge of water quality and related responsibilities; (2) a tension between broader inclusion and military involvement in river restoration; and (3) a diverse host of informal restoration practices that largely remain unnoticed in view of the government programs. The findings indicate that river governance can benefit from recognising and tuning into below-the-radar restoration practices to tackle river pollution.

High-frequency water quality measurements in streams and rivers have expanded in scope and sophistication during the last two decades. Existing technology allows in situ automated measurements of water quality constituents, including both solutes and particulates, at unprecedented frequencies from seconds to subdaily sampling intervals. This detailed chemical information can be combined with measurements of hydrological and biogeochemical processes, bringing new insights into the sources, transport pathways, and transformation processes of solutes and particulates in complex catchments and along the aquatic continuum. Here, we summarize established and emerging high-frequency water quality technologies, outline key high-frequency hydrochemical data sets, and review scientific advances in key focus areas enabled by the rapid development of high-frequency water quality measurements in streams and rivers. Finally, we discuss future directions and challenges for using high-frequency water quality measurements to bridge scientific and management gaps by promoting a holistic understanding of freshwater systems and catchment status, health, and function., Environmental Science & Technology, 57 (12), ISSN:0013-936X, ISSN:1520-5851

日本における河川水質は，高度成長期の1950～1960年代に著しく悪化したが，1970年の「水質汚濁防止法」などの法整備によって1980年代末には見違えるように改善された。しかし，人々が暮らす身近な地域での水環境としては，まだ問題のある地域が多いことは，既報（小寺，2022）の通りである。前稿でも，公的機関が行っている「公共水域の水環境調査」と市民団体を中心とした「身近な水環境の全国一斉調査」の結果を比較し，日本の河川水質の長期変化と特性について都道府県別のデータを中心に考察したが，本稿では，市町村別に分類したデータをもとに，さらに詳細な特性を示し，北海道地域についても具体的にデータを整理し，今後の研究の方向性を示した。, The water quality of rivers in Japan deteriorated significantly during the period of rapid economic growth in the 1950s and 1960s. As already reported (Kodera, 2022), there are still many areas with problems regarding the water environment in familiar areas. In my previous article, I compared the results of the "Survey of the Water Environment in Public Water Areas" conducted by a public institution and the "National Survey of Local Water Environments" conducted mainly by citizens' groups, and compared long-term changes in river water quality in Japan. Although we have focused on the characteristics by prefecture, this paper presents more detailed characteristics based on the data classified by municipality. In particular, we advanced concrete discussions on the Hokkaido region and indicated the direction of future research.

Labeo victorianus (Boulenger, 1901) is one of the endemic fishes in Lake Victoria Basin (LVB) but is now threatened by multiple stressors caused by human activities. We investigated spatial and temporal variability in food composition and condition of L. victorianus in influent rivers of Lake Victoria, Kenya. Sampling was done during the dry and wet seasons by electrofishing. Food composition analysis showed that L. victorianus is a benthophagus and omnivorous species whose diet is dominated by detritus, periphyton and insects. There were differences in food composition among rivers, with significant river X season interactions (PERMANOVA F = 11.6, df = 4, p = 0.001), suggesting that the diet depended on prevailing environmental conditions. In turbid rivers, the diet was dominated by detritus while in less turbid rivers it was dominated by insects and periphyton. Sand and mud also formed a significant part of the diet, which was an indication of a limited occurrence of preferable food items. There were ontogenetic shifts in food composition (PERMANOVA F = 4.6, df = 3, p = 0.001), but also with a spatial interaction (PERMANOVA F = 5.6, df = 7, p = 0.001), further indicating the role of environmental conditions in determining the diet for different size classes. Interestingly, the fish condition did not differ among rivers. This study shows that turbidity and organic matter and nutrient loading determine the diet of L. victorianus in LVB rivers, and provides further justification for the maintenance of water quality as a conservation measure for threatened species.

Stormwater reuse is one of the most important ways to mitigate water resource shortage. However, urban stormwater contains many bacteria species, which threaten the reuse safety. Therefore, stormwater disinfection is highly needed. Although disinfection has been widely conducted in the drinking water and reclaimed water, it is rarely carried out for stormwater. This study collected the roof stormwater and undertook chlorination disinfection. Two typical bacteria, Escherichia coli (E. coli) and Staphylococcus aureus (S.aureus) were selected in this study to investigate the disinfection efficiency. It is found that bacteria species present in the stormwater had an important influence on disinfection efficiency while the original stormwater quality did not show an obvious affect. However, when the disinfected stormwater was stored, the stormwater quality was highly variable during its storage process and the variability was affected by bacteria species. The S.aureus containing stormwater showed a high variability of quality and S.aureus significantly regrew. However, the E.coli containing stormwater quality had a relatively low variability and E.coli did not significantly regrew. Additionally, it is noted that after storage, the dissolved form of stormwater was more positive to the freshwater algae's growth while the particulate form (including bacteria and other particulate matters) was less. This implies that a further treatment such as filtration is needed before the stored stormwater is recharged into receiving waters in order to remove particulate forms. These research outcomes can provide useful insight to effective stormwater disinfection and ensure reuse safety.

The present study was undertaken from June 2015 to May 2017 in Tal Chhapar Wildlife Sanctuary (TWS), Churu, Rajasthan that represents one of the unique and important grassland ecosystems in the Thar desert of India but has not been assessed ecologically. In this work the water quality assessment of the area is carried out in terms of physicochemical parameters and water quality index to fill this gap. The surface water samples were collected from the water surface with two replicates per sampling occasion for the summer, monsoon, and post-monsoon seasons. The physicochemical analysis for eight parameters were carried out following prescribed methods, viz., pH-by pH meter, total dissolved solids (TDS) -gravimetric analysis and filtration, chloride- silver nitrate titration, sulphate- turbidimetric, phosphate-stannous chloride, nitrate-brucine, calcium- EDTA titration, and iron- calorimetric methods. The relationship between the parameters was analyzed using Pearson's correlation analysis, and the Canadian Council of Ministers of the Environment Water Quality Index (CCME WQI) was calculated from these parameters. The study revealed water to be slightly alkaline (7.27–7.63) in the area. Most of the physicochemical parameters of water were found to be within the acceptable limits of the Bureau of Indian Standards (BIS) except for TDS and phosphate. The TDS showed a very strong to moderate correlation with chloride (r = 0.97), iron (r = 0.79), sulphate (r = 0.58), and calcium (r = 0.52) that revealed these ions were the major components in the makeup of the dissolved solids in the water sample. The CCME WQI indicated the water quality was fair and suitable for drinking purposes for wildlife in the area. In absence of any such prior study in the area, the overall findings of the present work is highly significant that can be used by the management authorities for future environmental monitoring and holistic development of the area.

In Nigeria, over 120 million peoples use boreholes as their main source of drinking water and in-view of the increasing volume of solid waste materials in Maiduguri, it has become exigencies to evaluate the quality of borehole waters in the city. The objective of this paper is therefore to evaluate some physicochemical characteristic of borehole water samples in Maiduguri urban areas Borno State, Nigeria using standard methods. Result obtained revealed that the pH of all the water samples was within the range of 6.5 to 8.5 as recommended limit by World Health Organization (WHO). Except for the pH of borehole water at Bulumkutu ward which is acidic (6.2). The pHs of all the water from the three wards were alkaline. The total dissolved solid and the electrical conductivity of water samples from the three wards fall within the limit of WHO, except water samples from Ngarannam (1100 mg/l) and (2220 uS/cm). The concentration of major ions (Na, Mg and K) fall far below the WHO recommended limit and thus the water can said to be excellent in terms of these elements. Except for Cl ion (262 mg/g) at borehole water in Gwange ward fall above the permissible limit by WHO. The study recommends performing regular testing of different water sources within the study area to ensure that commensurate attention given is maintaining a healthy population.

International audience; The development of an integrated theory of subsurface drainage based on hydrology and hydrogeology concepts is presented. The historical context, the main hypothesis derived from the Boussinesq equation and the validation of the model predictions are discussed. Theoretical developments of this equation demonstrate that a single parameter (σ)-a combination of soil and drainage system properties-is sufficient for predicting the dynamics of subsurface drain flow rates. We also demonstrate that these drain flow rates are a function of the level of water replenishment in the system (classically the water table elevation), of the recharge intensity of the aquifer and of a buffer function related to the swelling or deflation of the water table shape during recharge events. For values of σ > 1, the buffer role of the water table is negligible. In that case approx. 13% of the water table recharge contributes to the flow rate, which is shown to explain the observed disconnection between water table elevations and peak flow rates at the outlet of classic agricultural drainage systems and to predict these peak flow rates accurately. A modelling approach based on this theory and validated experimentally (SIDRA model) allowed us to test the quality of the peak flow prediction. The SIDRA model also includes a surface runoff module and has been coupled to different modelling tools and used to analyse the impacts of subsurface drainage on water quality. The approach contributed towards the development of tools that helped to connect better the drainage systems to the hydrological functioning of watersheds.

The aim of this study is to determine the effect of giving sialang honey with different doses on the monetization of Betta fish (Betta sp). and to know the best dose for male betta fish. The method used in this study is an experimental method using a completely randomized design (CRD) with 5 treatments and 3 replications, namely: P0 (control), P1 (5 ml/L), P2 (6 ml/L), P3 (7 ml /L) and P4 (8 ml/L). The test fish used was obtained from a betta fish seller in Jalan Pasir Putih. The container used was a jar with a capacity of 10 liters as many as 15 pieces. The best results were obtained at P4 (8 ml/L) with the percentage of male sex directing success of 81.79%. The highest larval survival was found in treatment P4 (8 ml/L) at 78.89%. The results of the measurement of water quality parameters during the study temperature ranged from 28-32oC, pH 6.5-7, ammonia 0.08-0.58 ppm, DO 4.8-5.4 ppm. The brightness was 30-60 cm and the depth was between 0.9-1.1 cm.

Resumen El artículo describe las características fisicoquímicas y microbiológicas tanto del sistema de abastecimiento de agua potable existente en el distrito Las Brisas, ubicado en el cantón de Zarcero, como del agua superficial del río Jilguero que atraviesa dicha comunidad. Se valora el impacto negativo de las actividades humanas sobre el recurso hídrico durante los años 2019-2021 para determinar su vulnerabilidad a partir del análisis de 45 muestras de agua dulce. Los resultados más importantes son: 1- Existen niveles de amonio y de fosfato en el agua del acueducto, provenientes del expansivo desarrollo agropecuario, que, durante la estación lluviosa, escurren y lixivian a las nacientes. 2- El pH y el cloro libre son dos parámetros que requieren ser mejorados en el acueducto las Brisas, para reducir los riesgos y asegurar la potabilidad del agua en toda la red de distribución. 3- La contaminación del río Jilguero se clasifica entre moderada y severa según normativa nacional, situación generada por la intensa actividad agropecuaria en la zona, así como el irrespeto a las zonas de protección del río. Abstract The article describes the physicochemical and microbiological characteristics of both the existing drinking water supply system in the Las Brisas district located in the canton of Zarcero, and the surface water of the Jilguero River that crosses said community. The negative impact of human activities on water resources during the years 2019-2021 is assessed to determine its vulnerability based on the analysis of 45 freshwater samples. The most important results are: 1- There are levels of ammonium and phosphate in the aqueduct water that, during the rainy season, run off and leach into the springs, coming from the expansive agricultural development. 2- The pH and free chlorine are two parameters that need to be improved in the Las Brisas aqueduct, to reduce risks and ensure the potability of the water throughout the distribution network. 3- The contamination of the Jilguero River is classified between moderate and severe according to national regulations, a situation motivated by the intense agricultural activity in the area, as well as the disrespect for the river's protection zones.

The water quality index has been universally accepted as an indicator to represent the water quality status of the surface water body comprehensively. The prevalent conventional Water Quality Indices (WQIs) suffer from limitations such as 'eclipsing' and 'ambiguity'. Artificial intelligence techniques such as artificial neural networks (ANNs) have gained importance to overcome the limitations of conventional WQIs. In the present study, the Levenberg Marquardt (LM) algorithm and the Scaled Conjugate Gradient (SCG) algorithm have been compared to develop WQI based on the ANN approach (i.e ANNWQI). It is observed that the LM algorithm outperforms the SCG algorithm for prediction of ANNWQI of Indian streams, while the Bayesian Regularization algorithm has not been found suitable for the same purpose in the present study. It is also observed that both LM and SCG algorithm gives robust predictions when the hidden layer contains ten neurons. The combination of data set partitioning of training (75%), Validation (15%), and testing (10%) have been found to give the robust performance of prediction of ANNWQI for Indian streams. The predicted ANNWQI model using the LM algorithm has a very high correlation with the measured WQI values and therefore recommended to be adopted as an effective alternative, to avoid lengthy calculations involved in prevalent conventional WQI.

Pulsed electric field disinfection is an effective non-thermal water disinfection technology. Compared to conventional disinfection techniques, PEF inactivation has several advantages including no by-products. In this context, the use of silver ions in conjunction with a reverse osmosis filtration system has been proposed as a safe and cost-effective treatment approach that can be used in a point of use technologies. This system contains two silver meshes as electrodes inside a reverse osmosis membrane with the application of a pulsed electric field on it as a disinfection method, After conducting chemical and physical tests of the water samples before and after the treatment system, it was noticed that most of these characteristics were significantly affected by increasing the number of electrical impulses and the intensity of the applied voltage as a result of the increase in the ionization process of silver in water.

Groundwater vulnerability maps by numerical methods help to set priorities for identifying areas that are most affected by pollutants, enabling decision makers, departments and government agencies to save additional funds in the event of a groundwater monitoring and protection system for the entire study area.Numerical methods as SINTACS and Modified DRASTIC with GIS technologies are depended in this study. SINTACS Vulnerability Index (SVI) is based on seven parameters while Modified DRASTIC Index (MDI) is based on eight parameters but both methods are adopted weighted sum overlay of the parameters. Final results of SINTACS Vulnerability map depicts four classes from very low to high which varies from (77 to 144). About 82.81% of study area is classified under moderate vulnerability; the remaining 15.08% and 1.75% are under high and low vulnerability respectively. MD- DRASTIC vulnerability map ranges (85–179). This range of index values is divided into four classes including very low to high vulnerability classes. About (72.35%) of the study basin has moderate vulnerability. High vulnerability measured as a second effective class of the studied area with (20.5%). While low and very low areas comprise (6.45% and 0.6%) respectively. Comparative study of two vulnerability maps with water quality data represented by nitrate concentration showed that MD- DRASTIC method is more suitable to represent the real reality of pollution of the area.

In order to examine the effects of some physicochemical parameters on the zoobenthic community structure in Porsuk Stream, seasonal zoobenthic samples were collected from 6 stations between 2020-2021, and some physicochemical parameters were also measured. Within the scope of the study, a total of 30 families, 4 from the Gastropoda, 1 from the Bivalvia, 3 from the Clitellata, and 22 from the Insecta, were identified. Families Tubificidae, Erpobdellidae, and Chironomidae were identified at each station. Dominant groups in Porsuk Stream zoobenthos; Tubificidae (41.90 %), Chironomidae (16.68 %), Gammaridae (7.84), Valvatidae (6.16 %), Naididae (5.30 %), Asellidae (3.73 %), Physidae (% 3.48 %), Dreissenidae (3.16 %), Baetidae (3.07 %), Simuliidae (1.70 %), Erpobdellidae (1.69%) and Lymnaeidae (1.32 %), respectively. The highest dissolved oxygen value was measured in the Sobran Stream with an average of 11.3 mg/L. Detection of Caenidae from Ephemeroptera and Hydropsychidae from Trichoptera with low tolerance to pollution and results of the Canonical Correspondence Analysis in this station shows that dissolved oxygen concentration is effective on the distribution of taxa determined in the basin. At the same time, this station has the highest BMWP (64) and Shannon (2.22) values., Porsuk Çayı’nda bazı çevresel parametrelerin zoobentik komünite yapısı üzerine etkilerinin incelenmesi amacıyla 2020-2021 yılları arasında 6 istasyondan mevsimsel olarak zoobentik örnekler toplanmış ve aynı zamanda bazı çevresel parametreler de ölçülmüştür. Çalışma kapsamında Gastropoda sınıfından 4, Bivalvia sınıfından 1, Clitellata sınıfından 3, Insecta sınıfından 22 familya olmak üzere toplam 30 familya tespit edilmiştir. Tubificidae, Erpobdellidae ve Chironomidae familyaları her istasyonda tespit edilmiştir. Porsuk Çayı zoobentozunda baskın grupların; Tubificidae (%41,90), Chironomidae (%16,68), Gammaridae (7,84), Valvatidae (%6,16), Naididae (%5,30), Asellidae (%3,73), Physidae (%3,48), Dreissenidae (%3,16), Baetidae (%3,07), Simuliidae (%1,70), Erpobdellidae (%1,69) ve Lymnaeidae (%1,32) şeklinde sıralandığı görülmektedir. En yüksek çözünmüş oksijen değeri ortalama 11,3 mg/L ile Sobran Deresi’nde ölçülmüştür. Bu istasyonda kirliliğe toleransa düşük gruplardan Ephemeroptera takımından Baetidae ve Caenidae ve Trichoptera takımından Hydropsychidae familyalarının tespit edilmesi, havzada belirlenen taksonların dağılışına çözünmüş oksijen konsantrasyonun etkili olduğunu göstermektedir.

Water quality in freshwaters is declining worldwide due to increases in human populations, expansion of agricultural activities, and climate change. There are quite a number of regions of the world, Africa inclusive, that are understudied, and little to no baseline information exists related to water quality. This study was focused on the Bua River in Malawi, which supports sustenance fishing and basic needs for local communities. A portion of the river has elevated levels of protection because it is found within the Nkhotakota Wildlife Reserve. The focus of this study was to understand the spatial-temporal variations of water quality at five sites in the Bua River from May 2018 to June 2020 capturing the three main seasons (warm wet, cool dry, and hot dry). Although other water quality parameters did not vary spatially. Spatially, the Bua River mouth registered the highest values of Soluble reactive phosphorus and the Bua River upstream had the lowest. However, there were greater temporal differences across seasons for water temperature, water pH, and chlorophyll a. For instance, chlorophyll-a was higher during the hot dry season (3.28 µgL-1) compared to the cool dry season (2.10 µgL-1) and warm wet season (1.91 µgL-1). Water transparency, as measured by secchi depth was lowest during the warm wet season, which coincides with higher concentrations in SRP. All measurements of salt content, Electrical Conductivity (EC), Total Dissolved Solids (TDS), and salinity) were higher during the hot dry season and correlated negatively with SRP. Similarly, bicarbonate and alkalinity were also higher during the hot dry season. Principle Component Analysis indicated that the parameters responsible for variations of Bua River water quality are mainly related to soluble minerals, water temperature, and surface runoff associated with agricultural activities and domestic waste accounting for 78.49 % of the total variance in the data set.

The present article seeks to estimate water pollution with nitrogen and phosphorus and to analyse the territorial specifics in the content of those physicochemical variables along the length of a river. As a case area, the watercourse of the Osam River (Northern Bulgaria) is selected. Data concern the values of the following parameters: ammonium nitrogen (N-NH4), nitrate nitrogen (N-NO3), nitrite nitrogen (N-NO2), total nitrogen (N-tot), orthophosphates (P-PO4), and total phosphorus (P-tot), collected at four sampling points during the period 2015–2020. The assessment is based on the guidelines of Regulation 4/2012 for characterization of the surface waters. The spatial changes in the content of the examined variables are related to land use and for this purpose a map of CORINE Land Cover (2018) is prepared. The resulting information reveals that parameters with the most frequent excesses over the reference norm include N-NO3, N-tot, P-PO4, and P-tot, whose highest observed concentrations remain up to four times above the permissible limits for ”Good status” recommended in Regulation 4/2012. However, the reported values appear to be lower than those established for previous periods, which shows a positive tendency in water quality. There are also spatial features as moving from upstream to downstream – the upper part is contaminated with P-PO4 and P-tot due to the release of raw municipal and industrial effluents, while the lower section is loaded with N-NO3 and N-tot as a result of the excessive fertilization of arable lands. This work enriches past studies with new data for a recent period.

Deriving water quality benchmarks based on the species sensitivity distribution (SSD) is crucial for assessing the ecological risks of antibiotics. The application of extrapolation methods such as interspecies correlation estimation (ICE) and acute-to-chronic ratios (ACRs) can effectively supplement insufficient toxicity data for these emerging contaminants. Acute-to-chronic ratios can predict chronic toxicity from acute toxicity, and ICE can extrapolate an acute toxicity value from one species to another species. The present study explored the impact of two extrapolation methods on the reliability of SSDs by analyzing different scenarios. The results show that, compared with the normal and Weibull distributions, the logistic model was the best-fitting model. For most antibiotics, SSDs derived by extrapolation have high reliability, with 82.9% of R

This review tries to explain the effects of river infiltration and the interaction between groundwater and surface water on nitrogen (N) and phosphorus (P) distribution in riparian zones. On the basis of previous studies, this review summarized the distribution characteristics of N and P of 7 different riparian zones in China, compared the water quality of water bodies adjoining these riparian zones, proposed the distribution regularity of N and P in diverse riparian zones. The concentrations of N and P in the riparian zones with better water quality have increasing trend from riverside to upland. And those rivers with poorer water quality have decreasing trend. If the infiltrated concentration of runoff pollutant is more than river pollutant infiltration, the upland soil may obtain higher contaminants. On the contrary, if the concentration of river infiltration is more than that of the runoff, the riverside soil will show higher concentration. Similarly, if those two effects are equivalent, the concentration of N and P in the riparian zone will be low on riverside and upland, and somewhere in the middle will be higher than elsewhere. Clean rivers and polluted rivers taken with different quantity of contaminants will infiltrate diverse concentrations of N and P. It is expected that this review can provide a new theoretical basis for revealing the environmental effects of riparian zones and managing, protecting and restoring the riparian ecosystems.

This study is searching for some crucial physicochemical properties of groundwater samples collected from eleven outlets in Dakhla Oasis, Egypt, including the pH-value, electrical conductivity (EC), total dissolved solids (TDS), in addition to the concentrations of heavy metals and trace elements. In total 21 elements were analyzed using inductively coupled plasma spectrometry (ICP-OES). To categorize the water class: Chronic daily intakes (CDI), water quality index (WQI) and hazard risk (HR) were computed for the 21 elements in the water samples. Some biological parameters such as levels of urea, creatinine, and the tumor marker CEA were measured. The obtained results showed that the pH-values (6.12 to 6.56) for water samples are within the acceptable limits of the WHO. Results showed, also, that EC (274 to 532 μS/cm), TDS (175 to 340 ppm) besides, the level of measured 21 elements were lower than the values allowed by World Health Organization (WHO) and US Environmental Protection Agency (USEPA). Additionally, the reached data were comparable to other internationally published figures. It is emphasized that the data obtained for WQI confirmed that water from all the sampling points was of expedient quality. Based on the obtained data and the evaluated parameters, it can be concluded that the groundwater samples of the studied areas are of excellent quality; they do not pose any health risks to the local citizens, and are safe for their domestic consumption. Moreover, the results of urea, creatinine, and CEA analyses showed very few abnormal cases, which confirmed, again, that the groundwater in the studied areasdid not pose a risk to human health.

There is a surge of interest in reaching social and environmental justice in California's disadvantaged communities by governments, nongovernmental organizations, and academia. However, actions tak...

[EN] Exploitation of groundwater resources with no proper characterization of water reserves jeopardizes the quantity and quality of water available in the future. A major challenge is finding appropriate methods or coefficients to evaluate the carrying capacity of the aquifer. The objective of this study was to quantitatively and qualitatively characterize water reserves to provide information and management strategies for the rational use of available water resources in an alluvial aquifer in the Brazilian Northeastern semi-arid region. Shallow and medium-depth wells were analyzed. Water tables were monitored in the dry and wet seasons to calculate water reserves. Groundwater samples were collected for the determination of water quality for irrigation purposes. The increase in agricultural activities is jeopardizing the sustainability of the aquifer’s water, as reserves are not sufficient to meet this demand. Groundwater quality is not limiting for agricultural use. Converting surface irrigation into localized methods will potentially increase water productivity and consequently the irrigated area. This study provides data and makes it possible to recommend appropriate strategies for the exploitation of groundwater resources for the maintenance of agricultural activities under semi-arid conditions, and to avoid overexploitation., [PT] A explotação dos recursos hídricos subterrâneos sem a caracterização adequada das reservas hídricas compromete a quantidade e a qualidade da água disponível no futuro. Um grande desafio é encontrar métodos ou coeficientes apropriados para avaliar a capacidade de recarga do aquífero. Objetivou-se caracterizar qualiquantitativamente as reservas hídricas, com vistas a disponibilizar informações e estratégias de gerenciamento para o uso racional dos recursos hídricos disponíveis em um aquífero aluvial no semiárido do Nordeste brasileiro. Foram analisados poços rasos e de média profundidade. Os níveis estáticos dos poços foram monitorados nos períodos secos e chuvosos para calcular as reservas hídricas. Foram coletadas amostras de água para a determinação da qualidade da água para fins de irrigação. A constante ampliação de áreas para atividades agropecuárias está comprometendo a sustentabilidade hídrica do aquífero, uma vez que as reservas não são suficientes para atender a essa demanda. A qualidade das águas subterrâneas não é limitante para uso agropecuário. A conversão da irrigação por superfície em métodos localizados irá proporcionar o aumento da produtividade da água e, consequentemente, a área irrigada. O estudo fornece dados e permite recomendar estratégias apropriadas para a explotação dos recursos hídricos subterrâneos, com vistas à manutenção das atividades agropecuárias em condições semiáridas, de modo a evitar a superexplotação., This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) - Finance Code 001. Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq). Acknowledgments are also due to the Agência Estadual de Desenvolvimento do Ceará (ADECE), Secretaria de Desenvolvimento Econômico e Trabalho do Ceará (SEDET), Centro do Instituto de Educação Tecnológica (CENTEC), Fundação de Amparo à Pesquisa Científica e Desenvolvimento Tecnológico do Ceará (FUNCAP), and Chief Scientist Program, Brazil, for the financial support provided for this research and the award of scholarships.

Livestock production poses a threat to water quality worldwide. A better understanding of the contribution of individual livestock species to nitrogen (N) pollution in rivers is essential to improve water quality. This paper aims to quantify inputs of dissolved inorganic nitrogen (DIN) to the Yangtze River from different livestock species at multiple scales and explore ways for reducing these inputs through coupling crop and livestock production. We extended the previously developed model MARINA (Model to Assess River Input of Nutrient to seAs) with the NUFER (Nutrient flows in Food chains, Environment, and Resource use) approach for livestock. Results show that DIN inputs to the Yangtze River vary across basins, sub-basins, and 0.5° grids, as well as across livestock species. In 2012, livestock production resulted in 2000 Gg of DIN inputs to the Yangtze River. Pig production was responsible for 55-85% of manure-related DIN inputs. Rivers in the downstream sub-basin received higher manure-related DIN inputs than rivers in the other sub-basins. Around 20% of the Yangtze basin is considered as a manure-related hotspot of river pollution. Recycling manure on cropland can avoid direct discharges of manure from pig production and thus reduce river pollution. The potential for recycling manure is larger in cereal production than in other crop species. Our results can help to identify effective solutions for coupling crop and livestock production in the Yangtze basin.

Coral reefs are sensitive to environmental perturbations, and an unprecedented decline in corals has been reported globally as a result of increasing global and local stressors including excessive input of anthropogenic nutrients. This study investigated the effect of land-based sources of nutrients (N and P) associated with sewage, on ocean water quality and the health of corals in Mombasa Marine National Park and Reserve in Kenya to inform integrated coastal zone management and ocean governance. A year-long study was conducted to determine water quality according to protocols described in Grasshoff et al. (2007). Coral health status was also monitored using Underwater Visual Census (UVC) to record coral reef ecological parameters. The study area’s temperature, salinity, pH and dissolved oxygen were within the recommended standards for healthy coral reefs. The study indicated that land-based nutrients, Chlorophyll-a (Chl a) and total suspended solids (TSS), are the key factors affecting corals and could be the reason for the observed coral health, which ranged from fairly healthy to unhealthy. On average, nutrient concentrations were higher than recommended to maintain at least 50% coral coverage. Ammonia was the dominant form of nitrogen ranging from 0.105 to 0.4130 mg/l, while nitrate concentrations were 0.0348-0.0468 mg/l, indicating the possibility of blooming algal species in the area. Total suspended solids were above the recommended values, ranging between 33.5 and 79.3mg/l and Chl a 0.7114 and 1.58 μg/l. The study concluded that land-based nutrient load influenced coral reef health during the study period. It recommends that land-based pollution needs to be addressed as part of a holistic, integrated coastal zone management approach supporting practical, sustainable and legal management of nutrient discharge into the marine environment to preserve the water quality of Mombasa Marine National Park and Reserve.

Water-regulating ecosystem services (ESs) are a key factor in water supply for the population and the economy. In recent years, these ESs have been intensively included in regional and global assessments. However, the degree of knowledge of various water-regulating ESs and the availability of models for their estimation and mapping vary greatly. For example, most regional assessments currently do not take into account the ESs of moisture and precipitation recycling by forests which can lead to erroneous decisions on land use and forest management. To what extent is it possible to make adequate decisions on the basis of a partial assessment of the ESs? In this article, we discuss this problem using the example of boreal forests in the catchment of the Lake Kenozero in the north of the European part of Russia. Using the InVEST model, two ESs were quantified and mapped: water yield regulation due to evapotranspiration and water quality assurance due to prevention of soil erosion. The reduction in water yield due to evapotranspiration was estimated at 125 mm/year, and the prevention of soil erosion was estimated at 9.56 t/ha/year. Forest felling in the study area from 2007 to 2021 led to an increase in runoff and soil erosion by 6 mm/year and 0.03 t/ha/year, respectively. The hypothetical total instantaneous forest loss could lead to an increase in runoff and soil erosion by 71 mm/year and 2.44 t/ha/year, respectively. A tradeoff between these ESs was predictably identified as deforestation led to an increase in water yield and a deterioration in water quality due to soil erosion. The significance of a number of other water-regulating ESs for making regional decisions was expertly assessed. In particular, the importance of the ESs of precipitation recycling of sludge under climate change was discussed. Expanding the range of ESs under consideration increases the likelihood of choosing a protection strategy instead of a harvesting one in forest management.

Zarrineh Rud river is one of the most important rivers in northwest of Iran. In this study, QUAL2K simulation model was used. The simulation parameters in this study were collected from 5 sampling stations. The results showed that the amount of oxygen saturated solution of Zarrineh Rud river varied between 7–8 mg / l, which is higher than the maximum standard value required. The results showed that BOD could increase by 16%, respectively, and should decrease by 70%. The station S5 at the river downstream with 3.53 mg/L DO deficit was the most critical point, and the 26th kilometer of the river with a DO deficit of 2.05 mg/L was the most critical point for maintaining the aquatic life; therefore, some scenario must be developed for waste load reduction at this station. In order to improve the quality of Zarrineh Rud river, construction of a wastewater treatment plant is necessary for Miandoab sugar factory.

Humans and the environment are both concerned about contaminated drinking water. One of the most dangerous constituents in wastewater is heavy metals. The removal of these contaminants from the ecosystem is still a challenge. Some of these heavy metals have been toxic concentrations in human and livestock drinking water. As a result, the goal of this study was to compare the adsorption potential of non-treated and acid-treated activated carbon generated from maize cob in the treatment of wastewater. Fresh maize cobs were air-dried and oven-dried at 255 °C for 9 hours after being cleaned in distilled water. These were crushed, sieved through a 300 μm mesh and carbonized in a muffle furnace to produce powdered activated carbon (PAC). One half of PAC was treated with 780 mL of hydrochloric acid (acid-treated activated carbon - AAC), while the other received no further treatment (non-treated activated carbon - NAC). For surface characteristics and functional groups, the conventional approach was applied to characterize AAC and NAC. Thirty grams of each sample were used in the treatment of metal recycling effluent. Untreated (T1), filtered (T2), NAC treated (T3), and AAC treated (T4) wastewater samples were analysed in three replicates using World Health Organization (WHO) and Lagos State Environmental Protection Agency (LASEPA) standard methods for Physico-chemical parameters. Analysis of data was by ANOVA, while mean separation was by Duncan’s Multiple Range Test (DMRT) at (P ≤ .05). Results showed that T2 had no significant improvement (P ≤ .05) in all parameters tested. T3 significantly increased pH, conductivity, TS and TSS, gave the highest mean alkalinity, but showed no significant changes in heavy metal contents. T4 significantly improved mean colour, conductivity, nitrate content and DO, reduced mean pH (from 7.4±0 to 2.1±0.1), increased heavy metal concentrations (P ≤ .05) and increased mean total acidity, but not significantly (P ≥ .05). Treatments improved parameters in the following order: filtration < NAC < AAC. Thus, acid-activated carbon had a higher adsorbent capability than non-activated carbon due to its wide surface area and low moisture and ash contents.

Health-based drinking water violations affect about one in twelve Americans annually, yet the benefits of drinking water regulation are not well understood. I exploit plausibly exogenous variation in water quality violation timing to estimate the impacts on avoidance behavior and child outcomes. Using purchases of bottled water and common stomach remedies, emergency room visits for gastrointestinal illness, and school absences, I provide a comprehensive calculation of costs associated with poor drinking water quality. Individuals avoid the negative health impacts of coliform bacteria violations only when informed immediately. Timely public notification is a cost-effective way to induce avoidance behavior and protect health.

This study examined water samples from a local stream in Central Serbia, which was consumed as drinking water. The chemical parameters (chemical oxygen demand, COD; pH, total concentration of dissolved substances and electrical conductivity), the concentration of major, trace and radioactive elements in the water as well as the content of those from the environment, were examined. In addition, the microbiological quality of the water was inspected. The water samples were acidic (pH from 5·27–5·69) and COD ranged in upper permissible limits (up to 6·25 mg O2 l−1 [WR]). The concentrations of major, trace and radioactive elements, including radon, were below maximum contaminant levels. The water contained a higher number of total coliform bacteria (TCB) than it was allowed (˃10 colony-forming units (CFU) in 100 ml of water) as well as enterococci and Escherichia coli. The characterization of the isolated bacteria indicated that two isolates demonstrated proteolytic activity, while full antibiotic resistance was not detected. The isolates showed moderate to strong ability to produce biofilm, while the isolates of E. coli were nonpathogenic. The results indicated that examined water samples were not microbiologically and chemically safe, therefore, the usage of analysed water was not recommended as a water supply. Further research needs to include more frequent monitoring in order to propose measures for the improvement of the water quality and prevention of health risks for consumers.

In the United States, national chemical water quality criteria for the protection of aquatic life assume that aquatic ecosystems have sufficient resiliency to recover from criteria exceedences occurring up to once every 3 years. This resiliency assumption was critically reviewed through two approaches: (1) synthesis of case studies, and (2) population modeling. The population modeling examined differences in recovery of species with widely different life histories. One invertebrate (Hyalella azteca) and four fish species were modeled (fathead minnow, brook trout, lake trout, and shortnose sturgeon) with various disturbance magnitudes and intervals. The synthesis of ecosystem case studies showed generally faster recoveries for insect communities rather than fish, and recoveries from pulse (acute) disturbances were often faster than recoveries from press (chronic) disturbances. When the recovery dataset excluded severe disturbances that seemed unrepresentative of common facility discharge upsets that might cause criteria exceedences, the median recovery time was 1 year, 81% of the cases were considered recovered within 3 years, and 95% were considered recovered within 10 years. The modeling projected that short-lived fish species with high recovery times could thrive despite enduring 50% mortality disturbances every other year. However, long-lived fish species had longer recovery times and declined under the one disturbance every 3 years scenario. Overall, the analyses did not refute the long-standing judgements that 3 years is generally sufficient for recovery from nonrepetitive, moderate intensity disturbances of a magnitude up to 2× the chronic criteria in waters without other pollution sources or stresses. However, these constraints may not always be met and if long-lived fish species are a concern, longer return intervals such as 5-10 years could be indicated. Environ Toxicol Chem 2022;41:2887-2910. Published 2022. This article is a U.S. Government work and is in the public domain in the USA.

The Brazilian Cerrado biome provides relevant ecosystem services for Brazil and South America, being strategic for the planning and management of water resources as well as for agribusiness. The objective was to evaluate the water quality along the course of the Córrego da Formiga in a virgin portion of the Brazilian Cerrado, the relationship of land use with physical-chemical and biological parameters of the water, and the inflow of the tributary. Five water collection points were defined (between the source and mouth) and observed on a quarterly scale in 2015, water samples were collected and analyzed for physical-chemical and biological parameters in the laboratory, and flow measurements were performed at the same point and day of water collection. To identify and quantify land use and land cover (LULC) in the watershed, an image from the Landsat8-OLI satellite was obtained, and other geomorphological data from hypsometry (Topodata-INPE) were obtained to generate the slope, basin delimitation, and contribution area for each water collection point. The LULC percentages for each area of contribution to the water collection points were correlated with the physical-chemical and biological parameters of the water and submitted to multivariate analysis (PLS-DA) for analysis and grouping among the five analyzed points. Changes in water-quality patterns were more pronounced concerning the time when the first and last sampling was performed (rainy period) and may be influenced by the increase in the volume of water in these periods. The stream flow is highly variable over time and between points, with the lowest recorded flow being 0.1 L s−1 (P1) and the highest being 947.80 L s−1 (P5). Córrego da Formiga has class III water quality (CONAMA resolution 357), which characterizes small restrictions on the use of water for multiple uses. The soil cover with native vegetation is just over 12%, while the predominance was of the classes of sugar cane (62.42%) and pasture (19.33%). The PLS-DA analysis allowed separating the water analysis points between P1, P2, P3, and P5, while P4 was superimposed on others. It was also possible to verify that the parameters that weighed the most for this separation of water quality were pH, alkalinity_T, alkalinity_h, calcium, and hardness, all with a tendency to increase concentration from the source (P1) to the mouth (P5). As for water quality, it was also possible to verify that points P2 and P5 presented better water-quality conditions.

Water quality parameters such as temperature, dissolved oxygen, pH and total dissolved solids are important environmental factors affecting fish welfare. The deterioration of these parameters beyond the tolerance limits causes environmental stress and suppression of the immune system. Moreover, it allows opportunistic pathogens that are always present in the environment to infect immune-suppressed fish and cause serious disease outbreaks. In this study, water quality parameters and pathogenic bacteria profiles were monitored for 1 year in rainbow trout farms operating in the same river basin. Then, a data set was created considering the pathogenic bacteria in the diseased fish and the water quality parameters in the farm environment. Each of the water quality parameters in the data set was first used as an attribute and their order of importance in terms of disease outbreak was determined. Then, using multinomial logistic regression (MLR) analysis, which is one of the machine learning (ML) techniques, the possibility of water quality parameters revealing a disease outbreak was evaluated. Furthermore, very effective models that can be used to predict the probability of disease occurrence in trout farms with an accuracy of 95.65% have been created.

Wetland restoration is an important water quality and climate resilience strategy. Wetland restoration rarely considers tradeoffs at large spatial and temporal scales, which limits capacity to aid decision makers. High resolution data can reveal hundreds to thousands of possible restoration options across a landscape, but guidance for setting restoration targets at these scales is limited. This study uses structured decision making (SDM) as a process for evaluating the desirability of numerous restoration options, with a case study on the Outer Coastal Plain of the Chesapeake Bay watershed, USA. The Nature Conservancy, in partnership with federal, state, and nonprofit organizations, evaluated a decision to target large-scale wetland restoration based on two fundamental objectives: improve water quality and enhance climate resilience. A total of 964 potentially restorable alternatives were delineated across the study area. The alternatives were evaluated on seven water quality and climate resilience criteria. High-priority alternatives were mapped based on multi-criteria ranking methods and principal component analysis. Sensitivity analysis included varying nutrient load data, implementing multiple ranking methods with different assumptions, and varying criteria weights. The maps revealed seven distinct regions of restoration opportunities. Tradeoffs were evaluated to distinguish between desirable and less desirable regions. Results indicated that three regions were promising choices to initiate landowner engagement and outreach. This study highlights the advantages of SDM to structure large-scale restoration decisions. In doing so, our work offers a roadmap toward further developing SDM in future applied restoration contexts.

Biological communities in freshwater streams are often impaired by multiple stressors (e.g., flow or water quality) originating from anthropogenic activities such as urbanization, agriculture, or energy extraction. Restoration efforts in the Chesapeake Bay watershed, USA seek to improve biological conditions in 10% of freshwater tributaries and to protect the biological integrity of existing healthy watersheds. To achieve these goals, resource managers need to better understand which stressors are most likely driving biological impairment. Our study addressed this knowledge gap through two approaches: 1) reviewing and synthesizing published multi-stressor studies, and 2) examining 303(d) listed impairments linked to biological impairment as identified by jurisdiction regulatory agencies (the states within the watershed and the District of Columbia). Results identified geomorphology (i.e., physical habitat), salinity, and toxic contaminants as important for explaining variability in benthic community metrics in the literature review. Geomorphology (i.e., physical habitat and sediment), salinity, and nutrients were the most reported stressors in the jurisdictional impairment analysis. Salinity is likely a major stressor in urban and mining settings, whereas geomorphology was commonly reported in agricultural settings. Toxic contaminants, such as pesticides, were rarely measured; more research is needed to quantify the extent of their effects in the region. Flow alteration was also highlighted as an important urban stressor in the literature review but was rarely measured in the literature or reported by jurisdictions as a cause of impairment. These results can be used to prioritize stressor monitoring by managers, and to improve stressor identification methods for identifying causes of biological impairment.

Benthic macroinvertebrates can provide an integrated picture of environmental changes. Health of freshwaters can be assessed based on measured changes in the ecological structure of benthic macroinvertebrates. During the study period, 33 taxa were determined in Ilke Stream. As a result of principle component analysis (PCA), mainly nine components (T degrees C, EC, TDS, BOD5, NH4-N, NO2-N, NO3-N, PO4-P and CI-) account for 92% of the total variance among the water quality parameters. As a result of the UPGMA analysis, the highest similarity value was observed between the 1th and 2nd sampling points. SI, BMWP, ASPT and BBI indices were more proper than FBI index to determine the water quality of Ilke Stream. The results indicate that these indices should be adapted based on the ecological, geomorphological and environmental features of the regions.

The quality of the groundwater in the study area was evaluated through various water quality indexes for drinking and irrigation purposes. To evaluate the water quality index, 186 groundwater samples were sampled during 2 different seasons, likely pre-monsoon (PRM) and post-monsoon (POM). The collected samples were measured for physical-chemical parameters like pH, EC, TDS, Na, K, Ca, Mg, Cl, HCO3, PO4, SO4, NO3 and H4SiO4. The research findings indicated that groundwater of the study area is approaching an alarming stage of its suitability for drinking purpose because a major percentage (i. e. 56%: PRM, 46%: POM) of samples are within poor category. Thus, the proper management strategy for water resources must be developed and a preventive management practice to address this issue must be implemented. Various water quality parameters such as electrical conductivity (EC), pH, salinity hazard, sodium hazard and permeability indexes (PI) were considered for irrigation water quality evaluation and it is inferred that the groundwater of the study area is suitable for irrigation. The PRM and POM samples with higher Na + and Cl concentrations were identified. The primary source of groundwater contamination is anthropogenic factors like domestic, agriculture effluents and mining activities. However, the groundwater of these regions is also greatly influenced by geogenic factors like weathering, rock-water interaction and precipitation which results in groundwater water level fluctuation. The research findings suggest the groundwater quality of this region is approaching an alarming stage for drinking purposes. Thus, developing a management strategy for drinking water sources and implementing preventive management practices to address this issue becomes imperative.

This study was conducted to access the water quality of Qua River Estuary, Akwa Ibom state, Nigeria by collecting water samples and macroinvertebrates using standard sampling procedures and analytical methods. The mean values of physicochemical parameters assessed in water samples gave the following ranges: DO (2.38 – 4.63 mg/l), water temperature (26.13 – 29.18 oC), turbidity (22.56 – 39.24 NTU),TDS (224.8 – 332.51 mg/l), pH (6.3 – 7.5 mg/l), salinity (3.13 – 4.84 ppt),BOD (1.13 – 3.64 mg/l), nitrate (2.45 – 6.72 mg/l), phosphate (2.12 – 5.93 mg/l) and Flow velocity (0.23 – 0.38 ms-1). ANOVA reveals significant variation in some parameters. A total of 308 individual species, comprising of three phyla and seven taxonomic groups of macro-invertebrate were identified. Arthropoda constituted the highest percentage composition (75.4%), followed by Mollusca (18.8%), and Annelida (5.8%). The dominant group was Decapoda (35.7%) and the least was Odonata accounted only for 1.9%. Station 5 has the highest number of individual’s species (112), station 3 had the least (43). Chironomus plumosus was the most occurring species, accounted for 19.2%. The result reveals that anthropogenic activities in the water system influence the abundance of aquatic biota; based on the macro-invertebrates identified, it shows that the water quality is moderately polluted owing to human activities.

Increasing pressure on water resources in the world has revealed the necessity of using marginal water resources in irrigation. With the use of wastewater, which is one of the marginal water resources, the pressure on freshwater resources is alleviated, the discharge problems of wastewater are solved, and soil and crop productivity increase with the high nutritive effect of wastewater. However, salinity, heavy metals, some harmful chemicals, and the pathogen risks of wastewater should not be ignored. In this context, in this study, the effluent of the wastewater treatment plant located in the central Edremit district of Van province was evaluated in terms of usability in irrigation. Samples were taken from treated wastewater during the vegetation period in 2020 and 2021 and pH, EC, cation and anions, micro elements and heavy metal, total nitrogen and phosphorus, total suspended solids, chemical oxygen demand, biological oxygen demand, fecal coliform, percent sodium, sodium adsorption rate, residual sodium carbonate and Langelier saturation index were determined by analysis and calculations. As a result of the study, the treated wastewater does not pose a risk in terms of pH, EC, cation and anions, micro elements and heavy metal, total suspended solids, percent sodium, sodium adsorption rate, residual sodium carbonate, langelier saturation index and fecal coliform, but attention should be paid to the total nitrogen and phosphorus, chemical and biological oxygen demand contents. It was concluded that the treated wastewater is in compliance with national and international standards, and there is no harm in its use in irrigation and thus treated wastewater can be recommended as a reliable water source for irrigation in the semi-arid province of Van/Edremit. However, in order to ensure safe and sustainable management in irrigation with wastewater, it is necessary to monitor water quality and make necessary inspections of soil, crop and irrigation systems.

A 16 week experiment was conducted in earthen ponds in Iganga District of Eastern Uganda to investigate the effect of water quality on biomass production in Nile tilapia (Oreochromis niloticus L.) fed on peanut-based meals as alternative dietary fishmeal. Iso-nitrogenous diets containing 30% and 25% Crude Protein were applied for the first 12 weeks and last four weeks while the control was a local diet for Nile tilapia of 25% Crude Protein throughout the experiment. Treatments included the fishmeal-based diet and two peanut-based diets; peanut meal-based diet and mixed meal-based diet. Each of the 16 pond units measuring 3.0 x 4.0 x 1.0 were stocked with 48 fish fingerlings of 21.7 grams mean weight. Significant differences (p≤0.05) in mean values occurred among targeted parameters; pH, Dissolved Oxygen, nitrite nitrogen and unionized ammonia with exception to temperature. Apart from the unionized ammonia, the significant variations (p≤0.05) in water quality parameters did not significantly affect (p≥0.05) biomass production because they were maintained in suitable ranges for Nile tilapia.