To investigate the presence of metal elements and assess their health risk for the populace in the Nandong Underground River Basin(NURB),we conducted an analysis of eleven common heavy metals in the water body.A Healt...To investigate the presence of metal elements and assess their health risk for the populace in the Nandong Underground River Basin(NURB),we conducted an analysis of eleven common heavy metals in the water body.A Health risk assessment(HRA)model was employed to analyze 84 water samples from the NURB.The detection results revealed the following order of heavy metals concentrations:Fe>Al>Mn>Zn>As>Cd>Pb>Cr>Ni>Cu>Hg.Correlation analysis indicated a certain similarity in material source and migration transformation among these eleven metal elements.Our study identified that the health risks for local residents exposed to metal elements in the water of NURB primarily stem from carcinogenic risk(10^(−6)–10^(−4)a^(−1))through the drinking water pathway.Moreover,the health risk of heavy metal exposure for children through drinking water was notably higher than for adults.The maximum health risks of Cr in both underground and surface water exceeded the recommendation standard(5.0×10^(−5)a^(−1))from ICRP,surpassing the values recommended by the Swedish Environmental Protection Agency,the Dutch Ministry of Construction and Environment and the British Royal Society(5.0×10^(−6)a^(−1)).The results of the health risk assessment indicate that Cr in the water of NURB is the primary source of carcinogenic risk for local residents,followed by Cd and As.Consequently,it is imperative to control these three carcinogenic metals when the water was used as drinking water resource.展开更多
At present, there is relatively little research on the synergistic effects of heavy metals in soil, sediment, and bedrock on heavy metal pollution in water bodies. In this paper, heavy metals in soil, sediment, bedroc...At present, there is relatively little research on the synergistic effects of heavy metals in soil, sediment, and bedrock on heavy metal pollution in water bodies. In this paper, heavy metals in soil, sediment, bedrock, and water of a typical karst watershed in southwest China were investigated. The results indicated that the average values of heavy metals in soil and sediment were relatively higher than those in bedrock except for Ni and As. During the research period, As and Cd were the main heavy metal elements polluting the soil and sediment in the study area, while water bodies were mainly polluted by Ni, As, and Cd. The pollution assessment indicated that there were instances of poor or very poor water quality in the study area during the study period;the soil as a whole was slightly polluted by Cd and As;sediment was subject to moderate Cd pollution and mild As pollution. Analysis of geochemical form for heavy metals showed that heavy metals in soil and sediment were mainly in residual form, and the proportions of exchangeable As and Cd were relatively high. Multiple statistical analysis showed that heavy metals in sediment, soil, and bedrock explained 23.8%, 16.8%, and 16.2% of the changes in heavy metals of water, respectively. The research results can provide scientific basis for the prevention and control of heavy metal pollution in water bodies.展开更多
Groundwater is an important source of drinking water.Groundwater pollution severely endangers drinking water safety and sustainable social development.In the case of groundwater pollution,the top priority is to identi...Groundwater is an important source of drinking water.Groundwater pollution severely endangers drinking water safety and sustainable social development.In the case of groundwater pollution,the top priority is to identify pollution sources,and accurate information on pollution sources is the premise of efficient remediation.Then,an appropriate pollution remediation scheme should be developed according to information on pollution sources,site conditions,and economic costs.The methods for identifying pollution sources mainly include geophysical exploration,geochemistry,isotopic tracing,and numerical modeling.Among these identification methods,only the numerical modeling can recognize various information on pollution sources,while other methods can only identify a certain aspect of pollution sources.The remediation technologies of groundwater can be divided into in-situ and ex-situ remediation technologies according to the remediation location.The in-situ remediation technologies enjoy low costs and a wide remediation range,but their remediation performance is prone to be affected by environmental conditions and cause secondary pollution.The ex-situ remediation technologies boast high remediation efficiency,high processing capacity,and high treatment concentration but suffer high costs.Different methods for pollution source identification and remediation technologies are applicable to different conditions.To achieve the expected identification and remediation results,it is feasible to combine several methods and technologies according to the actual hydrogeological conditions of contaminated sites and the nature of pollutants.Additionally,detailed knowledge about the hydrogeological conditions and stratigraphic structure of the contaminated site is the basis of all work regardless of the adopted identification methods or remediation technologies.展开更多
Sairme mineral water, one of the famous mineral waters in Georgia, is renowned for its exceptional healing properties. The distinctiveness and therapeutic benefits of the naturally sourced mineral water, known as “Sa...Sairme mineral water, one of the famous mineral waters in Georgia, is renowned for its exceptional healing properties. The distinctiveness and therapeutic benefits of the naturally sourced mineral water, known as “Sairme”, stem from its rich array of microelements, notably including iron and manganese. Since 1948, the bottling of Sairme mineral water has been a prominent activity. Named after the Sairme deposit, this mineral water is packaged in various formats to cater to diverse consumer preferences. The bottling process involves transporting the mineral water from wells to the bottling plant through pipelines. Prior to bottling, the mineral water undergoes meticulous processing stages in adherence to current Georgian and international regulations. This process ensures that the concentration of trace elements in the bottled water is minimized, maintaining its purity and quality. Given the importance of preserving the microelements present in bottled mineral water, our research is dedicated to optimizing the technological process. Our objective is to safeguard the valuable microelements while ensuring the highest standards of quality and safety in the final product.展开更多
Turkey’s Eastern Anatolia Region is the oldest known mineral mining area of Maden and Alacakaya.Chromite production in the Alacakaya field constitutes 50% of the country’s exports,and copper mines in the Maden regio...Turkey’s Eastern Anatolia Region is the oldest known mineral mining area of Maden and Alacakaya.Chromite production in the Alacakaya field constitutes 50% of the country’s exports,and copper mines in the Maden region account for approximately 12% of the country’s copper production.There is a risk of water pollution due to significant mine waste which affects the Inci and Maden rivers.The water needs of many settlements are met from these streams,which run through these two mine sites.This study investigated the water pollution in the rivers.25 water samples were collected during the dry and rainy periods,and the Al,Cr,Cu,Fe,Li,Mn,Ni,Pb,Sr and Zn contents of these samples were examined in terms of health.Evaluation of element concentrations and creation of spatial distribution maps were performed using ArcGIS software.Spatial distribution maps,correlation and cluster analysis indicate that the source of heavy metals observed in waters is mine fields.The heavy metal content of the samples is higher in the dry period,the high concentration values are obtained from the mine sites,the decrease in the concentrations throughout the flow during the rainy period,are indicators of the effect of the mines on the water pollution.As a result of the comparison from the analysis results of water samples with World Health Organization(WHO),Environmental Protection Agency(EPA)and European Commission(EC)standards,the element values of Al,Cr,Fe,Mn,Ni and Pb exceeded the permissible values for health.The concentrations of these elements for dry period samples are:0-6.411 mg L^(-1),0.006-0.235 mg L^(-1),0-13.433 mg L^(-1),0-0.316 mg L^(-1),0-0.495 mg L^(-1),0-0.065mg L^(-1),and for rainy period samples are 0-1.698mg/L,0-0.2 mg L^(-1),0-9.033 mg L^(-1),0-0.173 mg L^(-1),0-0.373 mg L^(-1),0-0.034 mg L^(-1),respectively.Although the waters in the region are polluted by heavy metals,it has been determined that there is no noncarcinogenic hazard as a result of the calculation of the hazard index(HI<1)by ingestion and dermal contact within the scope of human health risk assessment.This study will be beneficial as it draws attention to the prevention of the negative effects of water pollution,which may cause serious health problems in the future as a result of mining activities in the region.展开更多
The problem of mine water source has always been an important hidden danger in mine safety production.The water source under the mine working face may lead to geological disasters,such as mine collapse and water disas...The problem of mine water source has always been an important hidden danger in mine safety production.The water source under the mine working face may lead to geological disasters,such as mine collapse and water disaster.The research background of mine water source identification involves many fields such as mining production,environmental protection,resource utilization and technological progress.It is a comprehensive and interdisciplinary subject,which helps to improve the safety and sustainability of mine production.Therefore,timely and accurate identification and control of mine water source is very important to ensure mine production safety.Laser-Induced Fluorescence(LIF)technology,characterized by high sensitivity,specificity,and spatial resolution,overcomes the time-consuming nature of traditional chemical methods.In this experiment,sandstone water and old air water were collected from the Huainan mining area as original samples.Five types of mixed water samples were prepared by varying their proportions,in addition to the two original water samples,resulting in a total of seven different water samples for testing.Four preprocessing methods,namely,MinMaxScaler,StandardScaler,Standard Normal Variate(SNV)transformation,and Centering Transformation(CT),were applied to preprocess the original spectral data to reduce noise and interference.CT was determined as the optimal preprocessing method based on class discrimination,data distribution,and data range.To maintain the original data features while reducing the data dimension,including the original spectral data,five sets of data were subjected to Principal Component Analysis(PCA)and Linear Discriminant Analysis(LDA)dimensionality reduction.Through comparing the clustering effect and Fisher's ratio of the first three dimensions,PCA was identified as the optimal dimensionality reduction method.Finally,two neural network models,CT+PCA+CNN and CT+PCA+ResNet,were constructed by combining Convolutional Neural Networks(CNN)and Residual Neural Networks(ResNet),respectively.When selecting the neural network models,the training time,number of iterative parameters,accuracy,and cross-entropy loss function in the classification problem were compared to determine the model best suited for water source data.The results indicated that CT+PCA+ResNet was the optimal approach for water source identification in this study.展开更多
The study investigates the hydrogeochemical characteristics of some towns in the Abakaliki Basin, comprising, Ishiagu, Aka Eze, Amaseri, Afikpo and Okposi communities, with the aim of sourcing for portable water in th...The study investigates the hydrogeochemical characteristics of some towns in the Abakaliki Basin, comprising, Ishiagu, Aka Eze, Amaseri, Afikpo and Okposi communities, with the aim of sourcing for portable water in the area. The basin is underlain by Albian sediments, essentially shales, in the lowlands, which were affected by low-grade metamorphism that had produced slates. The highlands comprise basic intrusives from episodes of magmatism and metallic ore mineralisation. Injection of brines into the aquifer system and low, seasonal aquifer recharge from rainfall results in poor water quality in the area. The study analyzes the geochemical distribution in water sources in the area and identifies sources of pollutants to guide the better choice of portable water. Results of hydrogeochemical analysis of both surface and groundwater from the communities were compared with World Health Organization to identify portable water locations in the area. While the salt lake at Okposi is the main source of brine intrusion in the study area, the Pb/Zn mine at Ishiagu is the main source of mine-water pollution in the study area. Most chemical parameters, (especially Cl<sup>-</sup>, Na<sup>+</sup>, Ca<sup>2+</sup>, Mg<sup>2+</sup>, SO<sub>4</sub><sup>2-</sup>, HCO<sub>3</sub><sup>-</sup>) maintain high concentrations within the salt lake area, with the values declining away from the salt lake. The main anthropogenic source of pollution in the area, especially at Ishiagu, is the indiscriminate surface mining of lead-zinc without proposer waste management practices. Possible sourcing for portable water in the study area includes a deep borehole at Ishiagu, away from lead-zinc intrusives. At the Okposi axis, searching for portable water in boreholes should target shallower aquifers that do not communicate with the deeper-seated brine zones, likewise targeting zones farther away from these brine-invaded areas. A controlled pumping rate could potentially ensure that the cone of depression was not low enough to reach the brine zone at depth. In addition, desalination could also potentially render the salt water drinkable if properly handled to eliminate the high concentration of salts in the water to the level of acceptable limit by the WHO. Based on the study, the best area to target for portable water in the study area is Afikpo, with most geochemical elements naturally occurring within WHO’s standard concentration while portable water could be harnessed in areas further away from mining sites, especially at deep groundwater.展开更多
A study aimed at evaluating the physicochemical and bacteriological quality of surface water was therefore carried out in a few watercourses in the municipality of Mbankomo, located in the Center Region (Cameroon). Th...A study aimed at evaluating the physicochemical and bacteriological quality of surface water was therefore carried out in a few watercourses in the municipality of Mbankomo, located in the Center Region (Cameroon). The physico-chemical parameters were measured according to the standard method. The organic pollution index (OPI) was determined from the contents of nitrates, phosphates, and ammoniacal nitrogen to characterize the level of organic pollution of the water. The microorganisms sought were total flora, indicators of faecal contamination like total coliforms, faecal coliforms, feacal streptococci and Escherichia coli, as well as the species Clostridium perfringens. The organic pollution index indicates a high-level organic pollution level during the small rainy season and high to moderate during the small dry season. High concentrations of the total and fecal coliforms, streptococci fecal, Escherichia coli and Clostridium perfringens respectively of 1712 × 10<sup>5</sup> CFU/100mL;82 × 10<sup>5</sup> CFU/100mL;10 × 10<sup>5</sup> CFU/100mL;27 × 10<sup>5</sup> and 40 × 10<sup>3</sup> CFU/100mL, all higher than WHO standards, indicate that the waterways of Mbankomo are subject to feacal pollution and harbor pathogenic microflora. The cell densities of main bacteria were significantly correlated with main abiotic parameters, such as Escherichia coli, which was significantly correlated with the pH of the water (r = 0.35;p < 0.05). The variation of organic pollution index category means correspond to a high level of organic pollution during the small rainy season and a high to moderate level during the small dry season. The deterioration of the quality of these waters is favored by their proximity to sources of pollution (toilets, plantation), the runoff of the waters contaminated, the use of detergents and wrong maintenance. These waters without any treatment are not recommendable for human consumption according to standards of the World Health Organization.展开更多
Rural environmental pollution is becoming more and more serious, which has become an important problem to be solved urgently in our country under the background of the new era. Protecting the ecological environment is...Rural environmental pollution is becoming more and more serious, which has become an important problem to be solved urgently in our country under the background of the new era. Protecting the ecological environment is one of the important functions of the government, and protecting the rural water environment is the unshirkable responsibility of the local governments. As the main body of rural water pollution control, how to define and fulfill the local governments’ responsibilities is of great significance to the advancement of the overall governance work. This paper starts from the local governments, which are the important main body of rural environmental governance. By comparing the similarities and differences between the performance of government responsibilities under the traditional governance model and the collaborative governance model, clarifies the governance responsibilities of the local governments. And further explores the effective measures for the government to play the main role, fulfill the main responsibilities, and participate in the collaborative governance of rural water pollution.展开更多
The deterioration of the surface water environment has become a serious challenge for water resources management due to increasing anthropogenic disturbance. Water resources protection requires control of potential po...The deterioration of the surface water environment has become a serious challenge for water resources management due to increasing anthropogenic disturbance. Water resources protection requires control of potential pollution sources. In this study, 99 water samples were collected from a river in a typical agricultural city of Anhui Province in eastern China, and these samples were analyzed in terms of pH, electrical conductivity, and the concentrations of F-, Cl-, SO42-, Na+, K+, Mg2+, Ca2+, As, Cr, Cu, Zn, and Pb. Cluster analysis, co-occurrence network analysis, and principal component analysis/factor analysis were conducted to qualitatively identify the potential sources of river water pollution in the study area. An absolute principal component score-multiple linear regression receptor model was used to quantitatively evaluate the contribution of each source to water quality parameters. The results showed that all observed water quality indices met the quality criteria specified in the Chinese drinking water standards, except for pH, ρ(F-), ρ(SO42-), and ρ(As). The heat map showed that the frequent recharge of pollutants from the tributaries during the wet season was the main reason for the deterioration of water quality. Five sources of river water pollution were identified, and their contribution ratios in a descending order were as follows: the geogenic process (24%) > agricultural activities (21%) > poultry farming sources (17%) > domestic pollution (9%) > transportation pollution (5%). Therefore, controlling pollution from agricultural activities, strengthening the regulation of livestock farming, and improving the sewage network are the recommended strategies for improving the quality of surface water resources in this area.展开更多
While bird populations are declining,the factors associated with this decline are unclear.Based on laboratory experiments,air pollution has long been recognized as a factor causing oxidative stress and adversely aff e...While bird populations are declining,the factors associated with this decline are unclear.Based on laboratory experiments,air pollution has long been recognized as a factor causing oxidative stress and adversely aff ecting bird health.Recently,studies employing an epidemiological approach have reported signifi cant declines in avian populations in Central Europe and the United States due to air pollution,and ozone in particular.We advocate that urgent actions are needed to mitigate these eff ects,which threaten biodiversity and environmental health,and propose a series of measures which can enlighten the path toward mitigating air pollution eff ects on avian populations.展开更多
The quality of surface waters is often altered by the presence of bacteria of faecal origin, as a result of untimely discharge of solid and liquid waste from households. The Sonfonia Lake located in the commune of Rat...The quality of surface waters is often altered by the presence of bacteria of faecal origin, as a result of untimely discharge of solid and liquid waste from households. The Sonfonia Lake located in the commune of Ratoma is under the influence of various forms of pollution resulting for the most part from anthropic activities. Field visits, interviews with resource persons and bacteriological analysis were carried out to assess the level of this pollution. Two water sampling campaigns were carried out during the low-water period and two others during the flood period of 2021. The comparison of the levels of faecal contamination bacteria in the present study with a previous one carried out in 2018 on the waters of the same lake, indicates an increase in the level of faecal coliforms and faecal streptococci that exceed the indicator values recommended by the WHO. These results show that Lake Sonfonia is polluted. This could be related to the increase in anthropogenic and demographic activities during the last four years. On the other hand, the analysis of the results showed the absence of pathogenic germs such as salmonella. The Mann-Whitney U statistical test was used to compare the value of the means of each of the variables observed during the two seasons.展开更多
Legacy mine shafts and waste dumps in the Witwatersrand continue to create social and environmental challenges for communities, even in areas where gold mining ceased over 100 years ago. The slow pace of eradication o...Legacy mine shafts and waste dumps in the Witwatersrand continue to create social and environmental challenges for communities, even in areas where gold mining ceased over 100 years ago. The slow pace of eradication of these gold mine shafts and waste dumps (or lack thereof) results in conflict between the communities and authorities, particularly the Department of Mineral Resources and Energy (DMRE) as the relevant authority in the field of environmental management in mining. This paper examines, through a literature review, the past and present legislative framework that resulted in legacy mine shafts and dumps and how communities find themselves living next to these mine sites, which results in social and environmental problems. The paper further explores the governments, particularly the DMRE, proposed initiatives to empower those who intend to extract value from the abandoned mines while curbing the scourge of crime in affected communities.展开更多
1,4-dioxane pollution is characterized by its early identification, widespread sources and extensive distribution. The pollutant is highly mobile and persistent in the water environment and is classified as a B2(proba...1,4-dioxane pollution is characterized by its early identification, widespread sources and extensive distribution. The pollutant is highly mobile and persistent in the water environment and is classified as a B2(probable) human carcinogen. After reviewing recent researches on the pollution status,transport and transformation characteristics of 1,4-dioxane in the water environment, as well as the environmental pollution remediation and treatment technologies, and the status of environmental regulation,this paper addresses that the distribution of 1,4-dioxane in water bodies is significantly correlated with chlorinated hydrocarbon pollutants such as 1,1,1-trichloroethane(1,1,1-TCA) and trichloroethylene(TCE).It is noteworthy that 1,4-dioxane often occurs in symbiosis with 1,1,1-TCA and has a similarity contamination plume distribution to 1,1,1-TCA. The natural attenuation of 1,4-dioxane in groundwater environment is weak, but there is a certain degree of biological oxidation attenuation. Current methods for treating 1,4-dioxane pollution mainly include extraction-treatment technology, advanced oxidation treatment technology, modified biological treatment technology and phytoremediation technology, all of which have their limitations in practical application. Currently, there is no environmental regulation available for the 1,4-dioxane pollution worldwide, and no enforceable standard established for defining the health trigger levels of 1,4-dioxane in drinking water. Research on this contaminant in China is generally limited to the site or laboratory scale, and there are no studies on the environmental risk and quality standards for 1,4-dioxane in the water environment.展开更多
The study of Borjomi mineral water deposit starts from the 30 s of XIX century. Chemical composition of Borjomi deposit mineral water is of great importance for study of issues of mineral water formation, creation of ...The study of Borjomi mineral water deposit starts from the 30 s of XIX century. Chemical composition of Borjomi deposit mineral water is of great importance for study of issues of mineral water formation, creation of geodynamic model of the deposit and increasing of useful resources. The impact of several strong earthquakes in the region on the wells of the deposit is described. Stability of chemical composition of Borjomi deposit mineral water is proved.展开更多
In order to understand the mechanism and regularity of the groundwater con- tamination from mine water of abandoned mines,experiments were conducted on an abandoned coal mine in Fuxin,a representative city with lots o...In order to understand the mechanism and regularity of the groundwater con- tamination from mine water of abandoned mines,experiments were conducted on an abandoned coal mine in Fuxin,a representative city with lots of mine water in northeast China.The groundwater pollution from different contaminants of coal-mining voids (total hardness,SO_4^(2-),Cl^-and total Fe) and pollution factors transportation situation in the coal rock were simulated by soil column experiment under the conditions of mine water leach- ing and main water leaching (similar to rainwater leaching),and the water-rock interaction mechanism was discussed during mine water infiltration through saturated coal rock by application of principle of mass conservation,based on physical properties of coal rock,as well as monitored chemical composition.The results show that,compared with the clear water leaching process,trends of change in pollutant concentrations presented different characteristics in the mine water leaching process.Groundwater is contaminated by the water rock interactions such as migration & accumulation,adsorption & transformation, dissolution & desorption and ion exchange during the mine water permeation.The expe- riments also suggest that at first dissolution rate of some kinds of dissoluble salts is high, but it decreases with leaching time,even to zero during both the mine water leaching and main water leaching.展开更多
Globally,groundwater contamination by nitrate is one of the most widespread environmental problems,particularly in arid and semiarid areas,which are characterized by low amounts of rainfall and groundwater recharge.Th...Globally,groundwater contamination by nitrate is one of the most widespread environmental problems,particularly in arid and semiarid areas,which are characterized by low amounts of rainfall and groundwater recharge.The stable isotope composition of groundwater(δ2H-H2O andδ18O-H2O)and dissolved nitrate(δ15N-NO3–andδ18O-NO3–)and factor analysis(FA)were applied to explore groundwater provenance,pollution,and chemistry evolution in the northwestern part of the Amman-Al Zarqa Basin,Jordan.In this study,we collected 23 samples from the Lower Ajloun aquifer in 2021,including 1 sample from a groundwater well and 22 samples from springs.These samples were tested for electrical conductivity,total dissolved solids,pH,temperature,dissolved oxygen,the concentration of major ions(Ca2+,Mg2+,Na+,K+,HCO3–,Cl–,SO42–,and NO3–),and the stable isotope composition of groundwater and dissolved nitrate.The results revealed that groundwater in the study area is mainly Ca–Mg–HCO3 type and can be classified as fresh water,hard water,and very hard water.The range and average concentration of NO3–were 3.5–230.8 and 50.9 mg/L,respectively.Approximately 33%of the sampling points showed NO3–levels above the maximum allowable concentration of 50.0 mg/L set by the World Health Organization(WHO)guidelines for drinking water quality.The values ofδ18O-H2O andδ2H-H2O showed that groundwater in the study area is part of the current water cycle,originating in the Mediterranean Sea,with significant evaporation,orographic,and amount effects.The values of the stable isotope composition of NO3–corresponded toδ15N-NO3–andδ18O-NO3–values produced by the nitrification process of manure or septic waste and soil NH4+.The FA performed on the hydrochemical parameters and isotope data resulted in three main factors,with Factor 1,Factor 2,and Factor 3,accounting for 50%,21%,and 11%of the total variance,respectively.Factor 1 was considered human-induced factor,named"pollution factor",whereas Factor 2,named"conservative fingerprint factor",and Factor 3,named"hardness factor",were considered natural factors.This study will help local researchers manage groundwater sustainably in the study area and other similar arid and semiarid areas in the world.展开更多
The relative abundance and weathering rate of minerals that produce and consume acidity dictates whether a mine water discharge will be acidic or alkaline. Because metal ion solubility generally decreases with increas...The relative abundance and weathering rate of minerals that produce and consume acidity dictates whether a mine water discharge will be acidic or alkaline. Because metal ion solubility generally decreases with increasing pH, acidic waters are associated with greater risk from dissolved metals loads, while alkaline waters area associated with environmental degradation due to the oxidative precipitation of iron as ochrous deposits in surface water channels. Pyrite weathering produces acidity and dissolved iron loads, while calcite and, to a lesser extent, alumino silicate minerals, provide neutralising capacity that helps maintain circumneutral pH. Relating the relative abundance of these source minerals in the mining environment, and their relative rates of weathering, provides a conceptual framework within which to develop risk assessment and risk management approaches to minewater pollution. In particular the lifetime of contamination, and time scales to reach improved or detereorated mine water discharge quality is critical when assessing environmental impacts and risk, and when choosing treatment technology or selecting other approaches to handling minewater pollution.展开更多
A multi-faceted Case Area Targeted Intervention (CATI) approach emphasizing the integration of Water, Sanitation and Hygiene (WASH) interventions and Oral Cholera Vaccine (OCV) campaign was employed to respond to the ...A multi-faceted Case Area Targeted Intervention (CATI) approach emphasizing the integration of Water, Sanitation and Hygiene (WASH) interventions and Oral Cholera Vaccine (OCV) campaign was employed to respond to the outbreak of cholera in Garissa County. Drinking water sources in areas heavily impacted by cholera were systematically mapped and tested for microbiological quality. The quality assessment was carried out in April 2023 during an ongoing cholera outbreak in the county. A total of 109 samples were collected and tested for thermotolerant coliforms and other in situ parameters. The finding revealed that more than 87% of the samples did not meet the World Health Organization (WHO) standard for thermotolerant coliforms;and 30% had turbidity values above the recommended threshold values. None of the 109 samples had any traceable residual chlorine. Following these findings, the county government implemented the targeted interventions which resulted in a positive impact in the fight against cholera. The WHO supported key interventions which included capacity building in water quality monitoring and prepositioning of critical WASH commodities to the cholera affected areas.展开更多
The primary objective of this study was to design and size a sustainable sanitation solution for the Ndiebene Gandiol 1 school located in the eponymous commune in northern Senegal. Field investigations led to the coll...The primary objective of this study was to design and size a sustainable sanitation solution for the Ndiebene Gandiol 1 school located in the eponymous commune in northern Senegal. Field investigations led to the collection of wastewater samples. Their analysis revealed specific pollutant loads, including loads of BOD5 3.6966 kgO<sub>2</sub>/day and COD of 12.8775 kgO<sub>2</sub>/day, which were central to the design phase. Following a rigorous assessment of the existing sanitation infrastructure, constructed wetland (CWs) emerged as the most appropriate ecological solution. This system, valued for its ability to effectively remove contaminants, was tailored to the specific needs of the site. Consequently, the final design of the filter extends over 217.16 m<sup>2</sup>, divided into two cells of 108.58 m<sup>2</sup> each, with dimensions of 12.77 m in length and 8.5 m in width. The depth of the filtering medium is approximately 0.60 m, meeting the standards while ensuring maximized purification. Typha, an indigenous and prolific plant known for its purification abilities, was selected as the filtering agent. Concurrently, non-crushed gravel was chosen for its proven filtration capacity. This study is the result of a combination of scientific rigor and design expertise. It provides a holistic view of sanitation for Ndiebene Gandiol. The technical specifications and dimensions of the constructed wetland filter embody an approach that marries indepth analysis and practical application, all aimed at delivering an effective and long-lasting solution to the local sanitation challenges. By integrating precise scientific data with sanitation design expertise, this study delivers a holistic solution for Ndiebene Gandiol. The detailed dimensions and specifications of the constructed wetland filter reflect a methodology that combines meticulous analysis with practical adaptation, aiming to provide an effective and sustainable response to the challenges of rural and school sanitation in the northern region of Senegal.展开更多
基金supported from the National Key Research and Development Program of China(No.2022YFF1302901)the Key Laboratory Construction Project of Guangxi(No.19-185-7)the Foundation for Hebei Education Department(No.2022QNJS05).
文摘To investigate the presence of metal elements and assess their health risk for the populace in the Nandong Underground River Basin(NURB),we conducted an analysis of eleven common heavy metals in the water body.A Health risk assessment(HRA)model was employed to analyze 84 water samples from the NURB.The detection results revealed the following order of heavy metals concentrations:Fe>Al>Mn>Zn>As>Cd>Pb>Cr>Ni>Cu>Hg.Correlation analysis indicated a certain similarity in material source and migration transformation among these eleven metal elements.Our study identified that the health risks for local residents exposed to metal elements in the water of NURB primarily stem from carcinogenic risk(10^(−6)–10^(−4)a^(−1))through the drinking water pathway.Moreover,the health risk of heavy metal exposure for children through drinking water was notably higher than for adults.The maximum health risks of Cr in both underground and surface water exceeded the recommendation standard(5.0×10^(−5)a^(−1))from ICRP,surpassing the values recommended by the Swedish Environmental Protection Agency,the Dutch Ministry of Construction and Environment and the British Royal Society(5.0×10^(−6)a^(−1)).The results of the health risk assessment indicate that Cr in the water of NURB is the primary source of carcinogenic risk for local residents,followed by Cd and As.Consequently,it is imperative to control these three carcinogenic metals when the water was used as drinking water resource.
基金Guizhou Provincial Key Technology R&D Program (2202023QKHZC).
文摘At present, there is relatively little research on the synergistic effects of heavy metals in soil, sediment, and bedrock on heavy metal pollution in water bodies. In this paper, heavy metals in soil, sediment, bedrock, and water of a typical karst watershed in southwest China were investigated. The results indicated that the average values of heavy metals in soil and sediment were relatively higher than those in bedrock except for Ni and As. During the research period, As and Cd were the main heavy metal elements polluting the soil and sediment in the study area, while water bodies were mainly polluted by Ni, As, and Cd. The pollution assessment indicated that there were instances of poor or very poor water quality in the study area during the study period;the soil as a whole was slightly polluted by Cd and As;sediment was subject to moderate Cd pollution and mild As pollution. Analysis of geochemical form for heavy metals showed that heavy metals in soil and sediment were mainly in residual form, and the proportions of exchangeable As and Cd were relatively high. Multiple statistical analysis showed that heavy metals in sediment, soil, and bedrock explained 23.8%, 16.8%, and 16.2% of the changes in heavy metals of water, respectively. The research results can provide scientific basis for the prevention and control of heavy metal pollution in water bodies.
基金funded by the National Natural Science Foundation of China(41907175)the Open Fund of Key Laboratory(WSRCR-2023-01)the project of the China Geological Survey(DD20230459).
文摘Groundwater is an important source of drinking water.Groundwater pollution severely endangers drinking water safety and sustainable social development.In the case of groundwater pollution,the top priority is to identify pollution sources,and accurate information on pollution sources is the premise of efficient remediation.Then,an appropriate pollution remediation scheme should be developed according to information on pollution sources,site conditions,and economic costs.The methods for identifying pollution sources mainly include geophysical exploration,geochemistry,isotopic tracing,and numerical modeling.Among these identification methods,only the numerical modeling can recognize various information on pollution sources,while other methods can only identify a certain aspect of pollution sources.The remediation technologies of groundwater can be divided into in-situ and ex-situ remediation technologies according to the remediation location.The in-situ remediation technologies enjoy low costs and a wide remediation range,but their remediation performance is prone to be affected by environmental conditions and cause secondary pollution.The ex-situ remediation technologies boast high remediation efficiency,high processing capacity,and high treatment concentration but suffer high costs.Different methods for pollution source identification and remediation technologies are applicable to different conditions.To achieve the expected identification and remediation results,it is feasible to combine several methods and technologies according to the actual hydrogeological conditions of contaminated sites and the nature of pollutants.Additionally,detailed knowledge about the hydrogeological conditions and stratigraphic structure of the contaminated site is the basis of all work regardless of the adopted identification methods or remediation technologies.
文摘Sairme mineral water, one of the famous mineral waters in Georgia, is renowned for its exceptional healing properties. The distinctiveness and therapeutic benefits of the naturally sourced mineral water, known as “Sairme”, stem from its rich array of microelements, notably including iron and manganese. Since 1948, the bottling of Sairme mineral water has been a prominent activity. Named after the Sairme deposit, this mineral water is packaged in various formats to cater to diverse consumer preferences. The bottling process involves transporting the mineral water from wells to the bottling plant through pipelines. Prior to bottling, the mineral water undergoes meticulous processing stages in adherence to current Georgian and international regulations. This process ensures that the concentration of trace elements in the bottled water is minimized, maintaining its purity and quality. Given the importance of preserving the microelements present in bottled mineral water, our research is dedicated to optimizing the technological process. Our objective is to safeguard the valuable microelements while ensuring the highest standards of quality and safety in the final product.
文摘Turkey’s Eastern Anatolia Region is the oldest known mineral mining area of Maden and Alacakaya.Chromite production in the Alacakaya field constitutes 50% of the country’s exports,and copper mines in the Maden region account for approximately 12% of the country’s copper production.There is a risk of water pollution due to significant mine waste which affects the Inci and Maden rivers.The water needs of many settlements are met from these streams,which run through these two mine sites.This study investigated the water pollution in the rivers.25 water samples were collected during the dry and rainy periods,and the Al,Cr,Cu,Fe,Li,Mn,Ni,Pb,Sr and Zn contents of these samples were examined in terms of health.Evaluation of element concentrations and creation of spatial distribution maps were performed using ArcGIS software.Spatial distribution maps,correlation and cluster analysis indicate that the source of heavy metals observed in waters is mine fields.The heavy metal content of the samples is higher in the dry period,the high concentration values are obtained from the mine sites,the decrease in the concentrations throughout the flow during the rainy period,are indicators of the effect of the mines on the water pollution.As a result of the comparison from the analysis results of water samples with World Health Organization(WHO),Environmental Protection Agency(EPA)and European Commission(EC)standards,the element values of Al,Cr,Fe,Mn,Ni and Pb exceeded the permissible values for health.The concentrations of these elements for dry period samples are:0-6.411 mg L^(-1),0.006-0.235 mg L^(-1),0-13.433 mg L^(-1),0-0.316 mg L^(-1),0-0.495 mg L^(-1),0-0.065mg L^(-1),and for rainy period samples are 0-1.698mg/L,0-0.2 mg L^(-1),0-9.033 mg L^(-1),0-0.173 mg L^(-1),0-0.373 mg L^(-1),0-0.034 mg L^(-1),respectively.Although the waters in the region are polluted by heavy metals,it has been determined that there is no noncarcinogenic hazard as a result of the calculation of the hazard index(HI<1)by ingestion and dermal contact within the scope of human health risk assessment.This study will be beneficial as it draws attention to the prevention of the negative effects of water pollution,which may cause serious health problems in the future as a result of mining activities in the region.
基金the Collaborative Innovation Center of Mine Intelligent Equipment and Technology,Anhui University of Science&Technology(CICJMITE202203)National Key R&D Program of China(2018YFC0604503)Anhui Province Postdoctoral Research Fund Funding Project(2019B350).
文摘The problem of mine water source has always been an important hidden danger in mine safety production.The water source under the mine working face may lead to geological disasters,such as mine collapse and water disaster.The research background of mine water source identification involves many fields such as mining production,environmental protection,resource utilization and technological progress.It is a comprehensive and interdisciplinary subject,which helps to improve the safety and sustainability of mine production.Therefore,timely and accurate identification and control of mine water source is very important to ensure mine production safety.Laser-Induced Fluorescence(LIF)technology,characterized by high sensitivity,specificity,and spatial resolution,overcomes the time-consuming nature of traditional chemical methods.In this experiment,sandstone water and old air water were collected from the Huainan mining area as original samples.Five types of mixed water samples were prepared by varying their proportions,in addition to the two original water samples,resulting in a total of seven different water samples for testing.Four preprocessing methods,namely,MinMaxScaler,StandardScaler,Standard Normal Variate(SNV)transformation,and Centering Transformation(CT),were applied to preprocess the original spectral data to reduce noise and interference.CT was determined as the optimal preprocessing method based on class discrimination,data distribution,and data range.To maintain the original data features while reducing the data dimension,including the original spectral data,five sets of data were subjected to Principal Component Analysis(PCA)and Linear Discriminant Analysis(LDA)dimensionality reduction.Through comparing the clustering effect and Fisher's ratio of the first three dimensions,PCA was identified as the optimal dimensionality reduction method.Finally,two neural network models,CT+PCA+CNN and CT+PCA+ResNet,were constructed by combining Convolutional Neural Networks(CNN)and Residual Neural Networks(ResNet),respectively.When selecting the neural network models,the training time,number of iterative parameters,accuracy,and cross-entropy loss function in the classification problem were compared to determine the model best suited for water source data.The results indicated that CT+PCA+ResNet was the optimal approach for water source identification in this study.
文摘The study investigates the hydrogeochemical characteristics of some towns in the Abakaliki Basin, comprising, Ishiagu, Aka Eze, Amaseri, Afikpo and Okposi communities, with the aim of sourcing for portable water in the area. The basin is underlain by Albian sediments, essentially shales, in the lowlands, which were affected by low-grade metamorphism that had produced slates. The highlands comprise basic intrusives from episodes of magmatism and metallic ore mineralisation. Injection of brines into the aquifer system and low, seasonal aquifer recharge from rainfall results in poor water quality in the area. The study analyzes the geochemical distribution in water sources in the area and identifies sources of pollutants to guide the better choice of portable water. Results of hydrogeochemical analysis of both surface and groundwater from the communities were compared with World Health Organization to identify portable water locations in the area. While the salt lake at Okposi is the main source of brine intrusion in the study area, the Pb/Zn mine at Ishiagu is the main source of mine-water pollution in the study area. Most chemical parameters, (especially Cl<sup>-</sup>, Na<sup>+</sup>, Ca<sup>2+</sup>, Mg<sup>2+</sup>, SO<sub>4</sub><sup>2-</sup>, HCO<sub>3</sub><sup>-</sup>) maintain high concentrations within the salt lake area, with the values declining away from the salt lake. The main anthropogenic source of pollution in the area, especially at Ishiagu, is the indiscriminate surface mining of lead-zinc without proposer waste management practices. Possible sourcing for portable water in the study area includes a deep borehole at Ishiagu, away from lead-zinc intrusives. At the Okposi axis, searching for portable water in boreholes should target shallower aquifers that do not communicate with the deeper-seated brine zones, likewise targeting zones farther away from these brine-invaded areas. A controlled pumping rate could potentially ensure that the cone of depression was not low enough to reach the brine zone at depth. In addition, desalination could also potentially render the salt water drinkable if properly handled to eliminate the high concentration of salts in the water to the level of acceptable limit by the WHO. Based on the study, the best area to target for portable water in the study area is Afikpo, with most geochemical elements naturally occurring within WHO’s standard concentration while portable water could be harnessed in areas further away from mining sites, especially at deep groundwater.
文摘A study aimed at evaluating the physicochemical and bacteriological quality of surface water was therefore carried out in a few watercourses in the municipality of Mbankomo, located in the Center Region (Cameroon). The physico-chemical parameters were measured according to the standard method. The organic pollution index (OPI) was determined from the contents of nitrates, phosphates, and ammoniacal nitrogen to characterize the level of organic pollution of the water. The microorganisms sought were total flora, indicators of faecal contamination like total coliforms, faecal coliforms, feacal streptococci and Escherichia coli, as well as the species Clostridium perfringens. The organic pollution index indicates a high-level organic pollution level during the small rainy season and high to moderate during the small dry season. High concentrations of the total and fecal coliforms, streptococci fecal, Escherichia coli and Clostridium perfringens respectively of 1712 × 10<sup>5</sup> CFU/100mL;82 × 10<sup>5</sup> CFU/100mL;10 × 10<sup>5</sup> CFU/100mL;27 × 10<sup>5</sup> and 40 × 10<sup>3</sup> CFU/100mL, all higher than WHO standards, indicate that the waterways of Mbankomo are subject to feacal pollution and harbor pathogenic microflora. The cell densities of main bacteria were significantly correlated with main abiotic parameters, such as Escherichia coli, which was significantly correlated with the pH of the water (r = 0.35;p < 0.05). The variation of organic pollution index category means correspond to a high level of organic pollution during the small rainy season and a high to moderate level during the small dry season. The deterioration of the quality of these waters is favored by their proximity to sources of pollution (toilets, plantation), the runoff of the waters contaminated, the use of detergents and wrong maintenance. These waters without any treatment are not recommendable for human consumption according to standards of the World Health Organization.
文摘Rural environmental pollution is becoming more and more serious, which has become an important problem to be solved urgently in our country under the background of the new era. Protecting the ecological environment is one of the important functions of the government, and protecting the rural water environment is the unshirkable responsibility of the local governments. As the main body of rural water pollution control, how to define and fulfill the local governments’ responsibilities is of great significance to the advancement of the overall governance work. This paper starts from the local governments, which are the important main body of rural environmental governance. By comparing the similarities and differences between the performance of government responsibilities under the traditional governance model and the collaborative governance model, clarifies the governance responsibilities of the local governments. And further explores the effective measures for the government to play the main role, fulfill the main responsibilities, and participate in the collaborative governance of rural water pollution.
基金supported by the 2021 Graduate Science Research Project of the Anhui Higher Education Institutions(Grant No.YJS20210375)the Natural Science Research Project of Universities in Anhui Province(Grant No.KJ2020ZD64)+2 种基金the Natural Science Foundation of Anhui Province(Grant No.2008085MD122)the Outstanding Young Talents in Higher Education Institutions of Anhui Province(Grant No.ZD2021134)the Research Development Foundation of Suzhou University(Grant No.2021fzjj28).
文摘The deterioration of the surface water environment has become a serious challenge for water resources management due to increasing anthropogenic disturbance. Water resources protection requires control of potential pollution sources. In this study, 99 water samples were collected from a river in a typical agricultural city of Anhui Province in eastern China, and these samples were analyzed in terms of pH, electrical conductivity, and the concentrations of F-, Cl-, SO42-, Na+, K+, Mg2+, Ca2+, As, Cr, Cu, Zn, and Pb. Cluster analysis, co-occurrence network analysis, and principal component analysis/factor analysis were conducted to qualitatively identify the potential sources of river water pollution in the study area. An absolute principal component score-multiple linear regression receptor model was used to quantitatively evaluate the contribution of each source to water quality parameters. The results showed that all observed water quality indices met the quality criteria specified in the Chinese drinking water standards, except for pH, ρ(F-), ρ(SO42-), and ρ(As). The heat map showed that the frequent recharge of pollutants from the tributaries during the wet season was the main reason for the deterioration of water quality. Five sources of river water pollution were identified, and their contribution ratios in a descending order were as follows: the geogenic process (24%) > agricultural activities (21%) > poultry farming sources (17%) > domestic pollution (9%) > transportation pollution (5%). Therefore, controlling pollution from agricultural activities, strengthening the regulation of livestock farming, and improving the sewage network are the recommended strategies for improving the quality of surface water resources in this area.
基金This study was supported by the National Natural Science Foundation of China(No.4210070867 and 42130714).
文摘While bird populations are declining,the factors associated with this decline are unclear.Based on laboratory experiments,air pollution has long been recognized as a factor causing oxidative stress and adversely aff ecting bird health.Recently,studies employing an epidemiological approach have reported signifi cant declines in avian populations in Central Europe and the United States due to air pollution,and ozone in particular.We advocate that urgent actions are needed to mitigate these eff ects,which threaten biodiversity and environmental health,and propose a series of measures which can enlighten the path toward mitigating air pollution eff ects on avian populations.
文摘The quality of surface waters is often altered by the presence of bacteria of faecal origin, as a result of untimely discharge of solid and liquid waste from households. The Sonfonia Lake located in the commune of Ratoma is under the influence of various forms of pollution resulting for the most part from anthropic activities. Field visits, interviews with resource persons and bacteriological analysis were carried out to assess the level of this pollution. Two water sampling campaigns were carried out during the low-water period and two others during the flood period of 2021. The comparison of the levels of faecal contamination bacteria in the present study with a previous one carried out in 2018 on the waters of the same lake, indicates an increase in the level of faecal coliforms and faecal streptococci that exceed the indicator values recommended by the WHO. These results show that Lake Sonfonia is polluted. This could be related to the increase in anthropogenic and demographic activities during the last four years. On the other hand, the analysis of the results showed the absence of pathogenic germs such as salmonella. The Mann-Whitney U statistical test was used to compare the value of the means of each of the variables observed during the two seasons.
文摘Legacy mine shafts and waste dumps in the Witwatersrand continue to create social and environmental challenges for communities, even in areas where gold mining ceased over 100 years ago. The slow pace of eradication of these gold mine shafts and waste dumps (or lack thereof) results in conflict between the communities and authorities, particularly the Department of Mineral Resources and Energy (DMRE) as the relevant authority in the field of environmental management in mining. This paper examines, through a literature review, the past and present legislative framework that resulted in legacy mine shafts and dumps and how communities find themselves living next to these mine sites, which results in social and environmental problems. The paper further explores the governments, particularly the DMRE, proposed initiatives to empower those who intend to extract value from the abandoned mines while curbing the scourge of crime in affected communities.
文摘1,4-dioxane pollution is characterized by its early identification, widespread sources and extensive distribution. The pollutant is highly mobile and persistent in the water environment and is classified as a B2(probable) human carcinogen. After reviewing recent researches on the pollution status,transport and transformation characteristics of 1,4-dioxane in the water environment, as well as the environmental pollution remediation and treatment technologies, and the status of environmental regulation,this paper addresses that the distribution of 1,4-dioxane in water bodies is significantly correlated with chlorinated hydrocarbon pollutants such as 1,1,1-trichloroethane(1,1,1-TCA) and trichloroethylene(TCE).It is noteworthy that 1,4-dioxane often occurs in symbiosis with 1,1,1-TCA and has a similarity contamination plume distribution to 1,1,1-TCA. The natural attenuation of 1,4-dioxane in groundwater environment is weak, but there is a certain degree of biological oxidation attenuation. Current methods for treating 1,4-dioxane pollution mainly include extraction-treatment technology, advanced oxidation treatment technology, modified biological treatment technology and phytoremediation technology, all of which have their limitations in practical application. Currently, there is no environmental regulation available for the 1,4-dioxane pollution worldwide, and no enforceable standard established for defining the health trigger levels of 1,4-dioxane in drinking water. Research on this contaminant in China is generally limited to the site or laboratory scale, and there are no studies on the environmental risk and quality standards for 1,4-dioxane in the water environment.
文摘The study of Borjomi mineral water deposit starts from the 30 s of XIX century. Chemical composition of Borjomi deposit mineral water is of great importance for study of issues of mineral water formation, creation of geodynamic model of the deposit and increasing of useful resources. The impact of several strong earthquakes in the region on the wells of the deposit is described. Stability of chemical composition of Borjomi deposit mineral water is proved.
基金the National Natural Science Foundation of China(50434020,50374042)Science & Technology Found of Liaoning Province(20022155)Specialized Research Fund for the Doctoral Program of Higher Education(20040147003)
文摘In order to understand the mechanism and regularity of the groundwater con- tamination from mine water of abandoned mines,experiments were conducted on an abandoned coal mine in Fuxin,a representative city with lots of mine water in northeast China.The groundwater pollution from different contaminants of coal-mining voids (total hardness,SO_4^(2-),Cl^-and total Fe) and pollution factors transportation situation in the coal rock were simulated by soil column experiment under the conditions of mine water leach- ing and main water leaching (similar to rainwater leaching),and the water-rock interaction mechanism was discussed during mine water infiltration through saturated coal rock by application of principle of mass conservation,based on physical properties of coal rock,as well as monitored chemical composition.The results show that,compared with the clear water leaching process,trends of change in pollutant concentrations presented different characteristics in the mine water leaching process.Groundwater is contaminated by the water rock interactions such as migration & accumulation,adsorption & transformation, dissolution & desorption and ion exchange during the mine water permeation.The expe- riments also suggest that at first dissolution rate of some kinds of dissoluble salts is high, but it decreases with leaching time,even to zero during both the mine water leaching and main water leaching.
基金funded by the Deanship of Scientific Research,Jordan University of Science and Technology(20210159).
文摘Globally,groundwater contamination by nitrate is one of the most widespread environmental problems,particularly in arid and semiarid areas,which are characterized by low amounts of rainfall and groundwater recharge.The stable isotope composition of groundwater(δ2H-H2O andδ18O-H2O)and dissolved nitrate(δ15N-NO3–andδ18O-NO3–)and factor analysis(FA)were applied to explore groundwater provenance,pollution,and chemistry evolution in the northwestern part of the Amman-Al Zarqa Basin,Jordan.In this study,we collected 23 samples from the Lower Ajloun aquifer in 2021,including 1 sample from a groundwater well and 22 samples from springs.These samples were tested for electrical conductivity,total dissolved solids,pH,temperature,dissolved oxygen,the concentration of major ions(Ca2+,Mg2+,Na+,K+,HCO3–,Cl–,SO42–,and NO3–),and the stable isotope composition of groundwater and dissolved nitrate.The results revealed that groundwater in the study area is mainly Ca–Mg–HCO3 type and can be classified as fresh water,hard water,and very hard water.The range and average concentration of NO3–were 3.5–230.8 and 50.9 mg/L,respectively.Approximately 33%of the sampling points showed NO3–levels above the maximum allowable concentration of 50.0 mg/L set by the World Health Organization(WHO)guidelines for drinking water quality.The values ofδ18O-H2O andδ2H-H2O showed that groundwater in the study area is part of the current water cycle,originating in the Mediterranean Sea,with significant evaporation,orographic,and amount effects.The values of the stable isotope composition of NO3–corresponded toδ15N-NO3–andδ18O-NO3–values produced by the nitrification process of manure or septic waste and soil NH4+.The FA performed on the hydrochemical parameters and isotope data resulted in three main factors,with Factor 1,Factor 2,and Factor 3,accounting for 50%,21%,and 11%of the total variance,respectively.Factor 1 was considered human-induced factor,named"pollution factor",whereas Factor 2,named"conservative fingerprint factor",and Factor 3,named"hardness factor",were considered natural factors.This study will help local researchers manage groundwater sustainably in the study area and other similar arid and semiarid areas in the world.
文摘The relative abundance and weathering rate of minerals that produce and consume acidity dictates whether a mine water discharge will be acidic or alkaline. Because metal ion solubility generally decreases with increasing pH, acidic waters are associated with greater risk from dissolved metals loads, while alkaline waters area associated with environmental degradation due to the oxidative precipitation of iron as ochrous deposits in surface water channels. Pyrite weathering produces acidity and dissolved iron loads, while calcite and, to a lesser extent, alumino silicate minerals, provide neutralising capacity that helps maintain circumneutral pH. Relating the relative abundance of these source minerals in the mining environment, and their relative rates of weathering, provides a conceptual framework within which to develop risk assessment and risk management approaches to minewater pollution. In particular the lifetime of contamination, and time scales to reach improved or detereorated mine water discharge quality is critical when assessing environmental impacts and risk, and when choosing treatment technology or selecting other approaches to handling minewater pollution.
文摘A multi-faceted Case Area Targeted Intervention (CATI) approach emphasizing the integration of Water, Sanitation and Hygiene (WASH) interventions and Oral Cholera Vaccine (OCV) campaign was employed to respond to the outbreak of cholera in Garissa County. Drinking water sources in areas heavily impacted by cholera were systematically mapped and tested for microbiological quality. The quality assessment was carried out in April 2023 during an ongoing cholera outbreak in the county. A total of 109 samples were collected and tested for thermotolerant coliforms and other in situ parameters. The finding revealed that more than 87% of the samples did not meet the World Health Organization (WHO) standard for thermotolerant coliforms;and 30% had turbidity values above the recommended threshold values. None of the 109 samples had any traceable residual chlorine. Following these findings, the county government implemented the targeted interventions which resulted in a positive impact in the fight against cholera. The WHO supported key interventions which included capacity building in water quality monitoring and prepositioning of critical WASH commodities to the cholera affected areas.
文摘The primary objective of this study was to design and size a sustainable sanitation solution for the Ndiebene Gandiol 1 school located in the eponymous commune in northern Senegal. Field investigations led to the collection of wastewater samples. Their analysis revealed specific pollutant loads, including loads of BOD5 3.6966 kgO<sub>2</sub>/day and COD of 12.8775 kgO<sub>2</sub>/day, which were central to the design phase. Following a rigorous assessment of the existing sanitation infrastructure, constructed wetland (CWs) emerged as the most appropriate ecological solution. This system, valued for its ability to effectively remove contaminants, was tailored to the specific needs of the site. Consequently, the final design of the filter extends over 217.16 m<sup>2</sup>, divided into two cells of 108.58 m<sup>2</sup> each, with dimensions of 12.77 m in length and 8.5 m in width. The depth of the filtering medium is approximately 0.60 m, meeting the standards while ensuring maximized purification. Typha, an indigenous and prolific plant known for its purification abilities, was selected as the filtering agent. Concurrently, non-crushed gravel was chosen for its proven filtration capacity. This study is the result of a combination of scientific rigor and design expertise. It provides a holistic view of sanitation for Ndiebene Gandiol. The technical specifications and dimensions of the constructed wetland filter embody an approach that marries indepth analysis and practical application, all aimed at delivering an effective and long-lasting solution to the local sanitation challenges. By integrating precise scientific data with sanitation design expertise, this study delivers a holistic solution for Ndiebene Gandiol. The detailed dimensions and specifications of the constructed wetland filter reflect a methodology that combines meticulous analysis with practical adaptation, aiming to provide an effective and sustainable response to the challenges of rural and school sanitation in the northern region of Senegal.
