Geogenic Factors Research Articles

Multivariate Exploratory Analysis of the Bulgarian Soil Quality Monitoring Network.

The goal of the present study is to assess the soil quality in Bulgaria using (i) an appropriate set of soil quality indicators, namely primary nutrients (C, N, P), acidity (pH), physical clay content and potentially toxic elements (PTEs: Cu, Zn, Cd, Pb, Ni, Cr, As, Hg) and (ii) respective data mining and modeling using chemometrical and geostatistical methods. It has been shown that five latent factors are responsible for the explanation of nearly 70% of the total variance of the data set available (principal components analysis) and each factor is identified in terms of its contribution to the formation of the overall soil quality-the mountain soil factor, the geogenic factor, the ore deposit factor, the low nutrition factor, and the mercury-specific factor. The obtained soil quality patterns were additionally confirmed via hierarchical cluster analysis. The spatial distribution of the patterns throughout the whole Bulgarian territory was visualized via the mapping of the factor scores for all identified latent factors. The mapping of identified soil quality patterns was used to outline regions where additional measures for the monitoring of the phytoavailability of PTEs were required. The suggested regions are located near to thermoelectric power plants and mining and metal production facilities and are characterized by intensive agricultural activity.

Occurrence, speciation, and controls on arsenic mobilization in the alluvial aquifer system of the Ghaghara basin, India.

High concentrations of arsenic (As) in groundwater are among the long-standing environmental problems on the planet. Due to adverse impacts on the human and aquatic system, characterization and quantification of individual inorganic As species are crucial in understanding the occurrence, environmental fate, behaviour, and toxicity in natural waters. This study presents As concentration and its speciation As(III) and As(V) data, including the interrelationship with other major and trace aqueous solutes from parts of the Ghaghara basin, India. More than half (57%) of the groundwater samples exhibited elevated As concentrations (> 10μg/L), whereas 67.4% of samples have higher As(III) values relative to As(V), signifying a potential risk of As(III) toxicity. The elevated concentration of As was associated with higher Fe, Mn, and HCO3-, especially in samples from shallow well depth. PHREEQC modeling demonstrates the presence of mineral phases such as hematite, goethite, rhodochrosite, etc. Therefore, it is inferred that the release of As from sediment particles into pore water via microbially mediated Fe/Mn oxyhydroxides, and As(V) reduction processes mainly control high As concentrations. The heavy metal pollution indices (HPI) and (HEI) values revealed heavy metal pollution in low-lying areas deposited by relatively younger sediments along the Ghaghara River. Large-scale agricultural practices, overexploitation of groundwater, and indiscriminate sewage disposal, in addition to geogenic factors, cannot be ruled out as potential contributors to As mobilization in the region. This study recommends conducting seasonal hydrogeochemical monitoring and investigating regional natural background levels of As, to precisely understand the controlling mechanistic pathways of As release.

Statistical Evaluation and Hydrogeochemistry of Groundwater from Western Part of Chandrapur District, Maharashtra with Special Emphasis on Human Health Risk Assessment

The groundwater samples were collected from the phreatic aquifers of PG2 watershed of western part Chandrapur district, Maharashtra. The geogenic processes like dissolution of calcium rich minerals are responsible for increase of Ca2+ content in groundwater. In the groundwater samples, HCO - and SO 2- are the prevailing dominant anions. The TDS, TH, Ca2+, Mg2+, Na+, HCO - as well as Cl- ions present in basement rocks have been attributed to the geogenic factor through the factor analysis. K+, SO 2- as well as NO - correspond to fertilizers and soil amendments used by people to enhance crop production, which is regarded as anthropogenic input. The silicate weathering at water-rock interface is the main process of generation of various solutes in groundwater. The multiple regression analysis expresses the TDS as a linear function of the ions and Ca2+, Mg2+, Na+, HCO -, Cl-, SO 2- and NO - contribute significantly to the bulk chemical composition of the groundwater from the study area. The health hazard quotient (HQ) for children (4.94%) and adults (7.95%) denotes the intensity of different health risk vulnerable zones at a specific site. Keywords: Rock-Water Interaction, Silicate Weathering, Statistical Evaluation, Health Risk Assessment, Chandrapur District, Maharashtra

Statistical Evaluation and Hydrogeochemistry of Groundwater from Western Part of Chandrapur District, Maharashtra with Special Emphasis on Human Health Risk Assessment

The groundwater samples were collected from the phreatic aquifers of PG2 watershed of western part Chandrapur district, Maharashtra. The geogenic processes like dissolution of calcium rich minerals are responsible for increase of Ca2+ content in groundwater. In the groundwater samples, HCO - and SO 2- are the prevailing dominant anions. The TDS, TH, Ca2+, Mg2+, Na+, HCO - as well as Cl- ions present in basement rocks have been attributed to the geogenic factor through the factor analysis. K+, SO 2- as well as NO - correspond to fertilizers and soil amendments used by people to enhance crop production, which is regarded as anthropogenic input. The silicate weathering at water-rock interface is the main process of generation of various solutes in groundwater. The multiple regression analysis expresses the TDS as a linear function of the ions and Ca2+, Mg2+, Na+, HCO -, Cl-, SO 2- and NO - contribute significantly to the bulk chemical composition of the groundwater from the study area. The health hazard quotient (HQ) for children (4.94%) and adults (7.95%) denotes the intensity of different health risk vulnerable zones at a specific site. Keywords: Rock-Water Interaction, Silicate Weathering, Statistical Evaluation, Health Risk Assessment, Chandrapur District, Maharashtra

Application of airborne geophysical survey data in a logistic regression model to improve the predictive power of geogenic radon maps. A case study in Castleisland, County Kerry, Ireland

In this study, a novel methodology was investigated to improve the spatial resolution and predictive power of geogenic radon maps. The data inputs comprise indoor radon measurements and seven geogenic factors including geological data (i.e. bedrock and Quaternary geology, aquifer type and soil permeability) and airborne geophysical parameters (i.e. magnetic field strength, gamma-ray radiation and electromagnetic resistivity). The methodology was tested in Castleisland southwest Ireland, a radon-prone area identified based on the results of previous indoor radon surveys. The developed model was capable of justifying almost 75 % of the variation in geogenic radon potential. It was found that the attributes with the greatest statistical significance were equivalent uranium content (EqU) and soil permeability. A new radon potential map was produced at a higher spatial resolution compared with the original map, which did not include geophysical parameter data. In the final step, the activity of radon in soil gas was measured at 87 sites, and the correlation between the observed soil gas radon and geophysical properties was evaluated. The results indicate that any model using only geophysical data cannot accurately predict soil radon activity and that geological information should be integrated to achieve a successful prediction model. Furthermore, we found that EqU is a better indicator for predicting indoor radon potential than the measured soil radon concentrations.

Scientific mapping of the research in microbial and chemical contamination of potable water in Bangladesh: A review of literature.

Drinking water contamination is one of the most pressing concerns for the people of Bangladesh as they rely on groundwater to meet their water needs. The existing water sources of Bangladesh are losing potability due to natural, anthropogenic, and geogenic factors, resulting in acute to severe health consequences. To address the issue of safe drinking water, researchers are constantly examining potential sources that cause the pollution of drinking water. Through bibliometric and systematic research, the current work seeks to review the past research on microbiological and chemical contamination of drinkable water in Bangladesh. The bibliometric review provides insights into the research trends, notable authors, countries, and institutions, whereas the systematic review unfolds the key research areas, the contamination process, and the strategies used to mitigate the contamination process. The results show that arsenic and various coliform bacteria are the most commonly reported sources of chemical and microbiological contaminants that degrade water quality. The study demonstrates that the most crucial factors influencing arsenic mobilization include microbial decomposition of organic matter (biologically available organic matter, for example, peat), arsenic adsorption by metal-oxyhydroxides, Fe-Mn oxyhydroxide, chemical fertilizers, pond excavation, and altering of groundwater hydrology. The studies also indicated the sources that contribute to the microbiological quality decline. The current work has addressed the scope of future research.

Nitrate health risk and geochemical characteristics of water in a semi-urban: implications from graphical plots and statistical computing

ABSTRACT The aim of this study was to assess the nitrate health risks due to water consumption via oral and dermal contact routes and to evaluate the geochemical characteristics of waters in the Umunya area, Nigeria, as implied from ionic ratios, graphical plots, and multivariate statistics. This study is the first to assess the human health risks associated with nitrate contamination in the semi-urban. Standard methods were used to achieve the aim of the study. Water from commercial and household sources were sampled. Measured physicochemical properties showed that the water resources are slightly contaminated. Health hazard quotient (oral) ranged from 0–0.5072 for men, 0–0.5994 for women, and 0–0.6858 for children. On the other hand, the maximum hazard quotient (dermal) for men, women, and children were 0.0013, 0.0016, and 0.0042, respectively. The total hazard index for men, women, and children respectively varied from 0–0.509, 0–0.601 and 0–0.690. Overall, it was indicated that 46.67%, 53.33%, and 53.33% of the water samples expose men, women, and children to low chronic health risk of nitrate. However, the risk for water ingestion was higher than that for dermal absorption. Hydrogeochemical plots revealed that Ca2+-Mg2+-HCO3 − and Na+-HCO3 − water types, representing recharge and base ion exchange processes, respectively, are predominant. Principal component analysis and R-type hierarchical clustering revealed that the hydrogeochemical characteristics are mostly controlled by geogenic factors than human-related factors. The geology of the area and silicate weathering processes were implicated as the major influencers of the hydrogeochemistry. For sustainable development and improved water monitoring in the area, the insights provided in this paper are considered very beneficial.

Resistance of domestic plum tree rootstocks against periodic overwatering of floodplain soils

This work investigates the effect of domestic plum rootstocks on the stability and productivity of Stanley plum plants. The main factor limiting the productivity of fruit crops in the floodplain soils of the foothill horticultural area of Krasnodar Oblast was found to be an unfavorable water-air regime of these soils in wet periods. The main geogenic factors that negatively affect the state and productivity of plum plants include the following: the presence of layers of low fertility and medium-clay granulometric composition in the soil profile. Depression and death of trees is promoted by prolonged overwatering of the upper part of the soil profile, caused by low filtration capacity of soil layers in combination with heavy granulometric composition and conditions of laying on the terrain (absence of horizontal surface runoff). A different degree of plum trees resistance to these unfavorable geogenic conditions depending on the type of rootstock was revealed. The lowest degree of depression under prolonged overwatering of the root-containing soil layer was observed in plum trees on the PK SK2 rootstock, which demonstrated the highest vegetative mass growth under the smallest number of dead plants. Stanley plum trees on rootstock AP1 were subjected to the greatest depression. The different degree of plum tree stability on different rootstocks is mainly related to the location of potentially active roots in the soil. The root system of plum trees on rootstock PK SK2 is characterized by the concentration of the main part (about 65 %) of potentially active roots in the upper soil layer of 0–40 cm. In plum trees on AP1 rootstock, potentially active roots penetrate to greater depths, with about 60% of the roots located in the soil layer of 40-80 cm. During wet periods and after abundant precipitation, when the soil below the 40 cm level is saturated with moisture, more than half of potentially active roots of plum trees on AP1 rootstock have to survive in unfavorable conditions.

Rock–water interaction, chemical weathering and solute transport of two rivers draining contrasting climate gradients in Western Ghats, India

AbstractRock–water interactions and chemical weathering are critical factors that determine the quality and quantity of solute transport in river catchments. However, most studies in this field have been limited to temperate regions and data from the tropics and subtropics are scarce, particularly for small rivers that are more responsive to environmental and climate changes. In this study, we investigated chemical weathering, its causal mechanisms and controlling factors that determine changes in the quality and quantity of solutes in two small, tropical mountainous rivers‐the west‐flowing Thuthapuzha river and the east‐flowing Bhavani river‐that drain through contrasting climate and geologic gradients across the southern part of the Western Ghats, in India. This region is an elevated passive continental margin and an ecologically sensitive area. Hydrochemical analysis of river water revealed that the cationic and anionic concentrations in the samples are in descending order of importance Ca2+ > Na+ > Mg2+ > K+ and HCO3− > Cl− > SO42−. Principal component analysis (PCA) indicated that geogenic factors (geology, chemical weathering and leaching/erosion) have a significant role in determining the hydrochemical characteristics of the rivers. To discriminate the relative contributions of silicate weathering in the river basins, we performed a detailed analysis of the major ion ratios along with forward and inverse modelling. The weathering index computed from the molecular ratio of cations and silica concentrations suggested that silicate weathering leads to kaolinite formation in the soil profile. The carbon dioxide consumption rate (CCR) estimated for the Thuthapuzha river, which is draining the humid western flank of the Western Ghats, was 2.18 × 105 mol·km−2 year−1, whereas the Upper Bhavani river, which is draining the semi‐arid area of the Western Ghats was 1.39 × 105 mol·km−2 year−1. Our study highlights the interplay of climatic factors and the geologic characteristics of the terrain that significantly influence the nature and characteristics of solute transport through the rivers in the study area.

Distribution and Statistical Analysis of Chemical Elements in Soil from the Territory of the Republic of Kosovo

ABSTRACT This research presents the results on the spatial distribution and concentration of different chemical elements in the topsoil (0–5 cm) and the subsoil (20–30 cm), focusing on the identification of natural and anthropogenic sources of elements at 99 locations and 198 samples throughout the territory of the Republic of Kosovo. The samples were digested with acid mixture in Teflon vessels and the technique of inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and mass spectrometry (ICP-MS) was applied for the analysis of 20 elements (Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, P, Pb, Sr, V and Zn). The multivariate statistical method was employed for the statistical processing of the data using cluster and factor analysis. Four groups of elements were identified, three of which were with geogenic factors: (Co, Cr, Ni, Fe, Mg), (Ba, K, Na, V), (Al, Ca, Sr) and one with local enrichment tendencies (anthropogenic origin) (Pb, Zn). The data obtained show natural presence of the analyzed elements and low concentration of heavy metals in the entire territory of Kosovo, with the exception of some areas where higher levels of concentration are shown as a result of the influence of the anthropogenic factor.

Identification of Sources and Mobilization of Trace Elements in Shallow Groundwater of the Upper Ganges River Basin

The concentration of trace metals in groundwater is still not within the usual standards established by the national and international monitoring authorities. This study aims to evaluate the sources and distribution of trace metals in the shallow aquifer water of the Ganges River basin in the Bangladesh area. A total of 40 groundwater samples were collected and investigated for 11 trace elements and some selected water parameters followed by sophisticated methods. The results presented that three metals, viz. Fe, Mn, and Pb crossed the limit of WHO standard in most of the samples (70-100%), representing severe human health hazards. Besides, the samples are slightly acidic to basic and highly mineralized by divalent cations and bicarbonate because total hardness was found very high. To assess factors affecting the trace metal loads in groundwater samples and determine their possible sources and mobility, multivariate statistical techniques, including Pearson’s correlation coefficient, principal components analysis, and dendrogram cluster analysis are performed. Results revealed that sources of trace elements were identified to be geologic and little from human activities, i.e., application of agrochemicals, excess water mining, and industrial wastewater. It was recognized that the elevated concentration of trace elements in samples was caused by geogenic factors rather than manmade activities. Groundwater in this area poses a large threat due to high levels of trace metals, without any purification, it is essential to avoid this water for drinking. It advised that the groundwater quality should be constantly monitored for sustainable water quality management in the study zone.

Hydrogeochemical characterization of groundwater in the shallow aquifer system of Middle Ganga Basin, India

Middle Ganga Basin (MGB) is lifeline for millions of inhabitants relying heavily on the groundwater. This has resulted in depletion of water quality and quantity at a very rapid scale. The present study has emphasized on hydrogeochemical evolution of groundwater in the Middle Ganga Basin, covering an area of 99,058 sq. km. Around 400 water samples were evaluated to determine the geochemical evolution of the shallow groundwater in MGB. The weighted average water quality index (WAWQI) shows 20.2% of the groundwater are unsuitable for drinking purposes. The Ca–HCO3 water facies dominates in northern region in the interfluves of Ghaghara and West Rapti rivers whereas more evolved water types such as Mg–HCO3, Na–HCO3 are found in the interfluves area of Ghaghara, Ganga, Yamuna, and Gomati Rivers. The occurrence of more mineralized water with increasing residence time in the flow direction suggests geogenic control and evolution follow the Chebotarev sequence. The saline water type is observed in and around the settlement reflecting the in-situ enrichment due to stagnation and anthropogenic activities. Hierarchical cluster analysis classified the regional groundwater data into three distinct major groups G1, G2, and G3. Factor 1 is attributed to anthropogenic inputs and associated with subgroup G2B and group G3. Factor 2 is attributable to the geogenic factors and is associated with subgroups G1A, G1B, and G2A. The various bivariate plots confirm the dominance of silicate weathering over carbonate weathering in the study area. Geochemical mass balance modeling suggests calcite and dolomite are in saturation to oversaturation conditions, restricting their further dissolution and primary silicate minerals controlling the groundwater chemistry. Our work reveals hydrogeochemical evolution on a regional scale in the shallow groundwater which will help to develop sustainable groundwater management strategies.

Conventional and advanced detection approaches of fluoride in water: a review.

Fluorine is a naturally occurring element found in soil, water, food materials, and natural minerals such as fluorapatite, sellaite, and cryolite and exists as fluoride compounds with other elements because of high reactivity. The exposure of fluoride to the environment and human beings are industrial factors, food, water, and geogenic factors that impact the health of millions of human beings worldwide. Overexposure to fluoride exceeding the permissible limit (1.5mg/l as per WHO) causes several diseases in human beings, such as teeth mottling, thyroid inflammation, dental fluorosis, skeletal fluorosis, lesions in the kidney, and other organs. To overcome the deleterious impact of fluoride, its detection at an early stage is very much required. Therefore, feeling the importance of the same, immense efforts have been made to the selective and sensitive determination of fluoride in water by numerous researchers. This review paper summarizes the various conventional methods such as spectroscopic, ion chromatography, ICP-OES, and gas chromatography-mass spectrometry, their advantages, and drawbacks leading to the development of advanced ready-to-use detection strategies such as stamartphones for on-the-spot fluoride detection. This review paper also discusses future directions, which will assist scientists in achieving a new benchmark in developing a reliable, cost-effective, and user-friendly fluoride detector.

Applied multivariate statistical analysis as a tool for assessing groundwater reactions in the Niebla-Posadas aquifer, Spain

In the current context of population growth and climate change, it is essential to effectively manage groundwater resources, to improve their quality, and to determine the behaviour of certain contaminants. Groundwater quality can be worsened most often by anthropogenic factors but can also be altered by natural factors depending on the chemical signatures of water sources (i.e., hydrochemical reactions) as a result of mixing processes. In these cases, the use of mixing calculations and multivariate statistical analysis (MSA) methods is crucial for determining the reactions that occur, the origin and fate of the detected compounds, ions or parameters, and the behaviour of the system. Thus, these methods ascertain processes that affect the chemical composition (i.e., quality) of groundwater bodies, and this information is needed for designing groundwater management strategies that exploit aquifers in a sustainable way. However, these methods are rarely employed, as few investigations that consider them focus on urban aquifers. Here, mixing calculations and other MSA methods that consider major ions and environmental isotopes are utilized in an aquifer located in a rural area associated with the Niebla-Posadas aquifer, Spain, where groundwater quality has deteriorated due to geogenic factors. This study proves the usefulness of these methods for deriving essential information that is needed (1) to properly manage the exploitation of aquifers, (2) to avoid the deterioration of groundwater bodies, and (3) to identify the reasons behind poor groundwater quality.

ASSESSMENT AND EVALUATION OF STORAGE VESSEL’S IMPACT ON PHYSICOCHEMICAL PROPERTIES OF BOREHOLE WATER FOR IRRIGATION AND DOMESTIC USE SUITABILITY

The impact of storage vessels on stored water quality changes and how it can influence plant growth, and human health through irrigation and domestic uses has been evaluated. The water was collected from the same borehole source at Ebonyi State University and stored in vessels made of plastic, metal, calabash, and clay pot. The samples were tested in the laboratory to ascertain the physiochemical quality of the water. The following ions Cd, Pb, Ca2+, Na+, Mg2+, K+, and Cl- were identified in each of the storage vessels which vary from the values of the controlled sample and were below their respective WHO permissible limits, except Cd which is significantly higher than WHO limit (>0.0003mg/l). The variation in qualities (odour, taste, colour, and metal concentration) of stored samples implies a significant influence of storage vessels on water quality. The pH range changed to slight alkali and hardness ranges from 160 to 330 mg/l after storage. The non-uniformity of each of the tested parameters among the samples indicated that each vessel had a different degree of impact on water quality during storage. The irrigation parameter and domestic use assessment showed some level of the potential risk to crops and humans mostly indicated by the MAR of calabash and Cd concentration respectively. The significant decrease in Cl- after storage suggests Cl decay, this enhances quality deterioration as microbial growth can be accelerated. The research conclusively noted that water quality deterioration is not an isotropic result of storage vessel influence but an integral impact of storage culture and geogenic factors’ influence on the water before and during storage and varying environmental constraints.

Large scale occurrence of aluminium-rich shallow groundwater in the Pearl River Delta after the rapid urbanization: Co-effects of anthropogenic and geogenic factors

Aluminium(Al)-rich (> 0.2 mg/L) groundwater has received more concerns because of its harmful to human beings. Origins of large-scale occurrence on Al-rich groundwater in urbanized areas such as the Pearl River Delta (PRD) are still little known. The current work was conducted to investigate spatial distribution of Al-rich groundwater in the PRD, and to discuss its origins in various aquifers. For that, 265 groundwater samples and 15 river water samples were collected, and 21 hydrochemical parameters including Al were analyzed by using conventional analytical procedures. The results showed that groundwater Al concentrations were up to 22.64 mg/L, and Al-rich groundwater occurred in 15% of the area occupied by the PRD. Al-rich groundwater in the coastal-alluvial aquifer was about 2 times those in alluvial-proluvial and fissured aquifers, whereas the karst aquifer was absent. In the coastal-alluvial aquifer, Al-rich groundwater in the peri-urban area was 2 or more times those in urbanized and agricultural areas, whereas the remaining area was absent. By contrast, in the alluvial-proluvial aquifer, Al-rich groundwater in the remaining area was 1.5–3.5 times that in other areas; in the fissured aquifer, the distribution of Al-rich groundwater was independent of land-use types. The infiltration of wastewater from township enterprises was main anthropogenic source for Al-rich groundwater in urbanized and peri-urban areas, whereas irrigation of Al-rich river water was the main one in the agricultural area. Naturally dissolution of Al-rich minerals in soils/rocks, triggered by both of pH decrease resulted from nitrification of contaminated ammonium (e.g., sewage leakage, the use of nitrogen fertilizer) and acid deposition, was the main geogenic source for Al-rich groundwater in the PRD. The contribution of anthropogenic sources to Al-rich groundwater in the coastal-alluvial aquifer was more than that in alluvial-proluvial and fissured aquifers, whereas the contribution of geogenic sources was opposite. In conclusion, the discharge of township enterprises wastewater and ammonium-rich sewage, the emission of nitrogen-containing gas, and the use of nitrogen fertilizer should be preferentially limited to decrease the occurrence of Al-rich groundwater in urbanized areas such as the PRD.

Pedodiversity of Subboreal Ecosystems under Contrasting Geogenic Factors (Case Study of Samarskaya Luka, Middle Volga Region, Russia)

The soils of uplands and partially isolated landforms located in the central Volga region were investigated in terms morphology, diversity and geogenic factor specificity. The Samarskaya Luka area is characterized by extreme spatial inhomogeneity and contrast of geogenic (lithological and topographic) conditions, and at the same time is located on the ecotone-transitional border of several natural zones. This territory is a part of two federal protected areas because of its peculiar nature. It is established that the diversity of geogenic (geological and topographic) conditions leads to the differentiation of the soil cover. Key soil types are presented by Leptosols, Cambisols, Retisols, Chernozems, Fluvisols and Technosols. By the example of the recognized upland macrolandscape, it is shown that the usual gradual course of soil zonation significantly changes due to the transformation of the soil-forming potential of the environment. The obtained data can be used for further regional verification of soil taxonomy. In addition, since the role of parent materials increases as they move from the west to the east of the East European Plain, parameterization of the role of this process becomes particularly important. Information about the diversity of chemical parameters and the granulometric composition of the key soil types of the studied area is also given.

Geochemical Assessment of Mineral Resource Potential in a Hg-Sb-Pb-Zn Mining Area: The Almadén and Guadalmez Synclines (South-Central Spain)

The geochemical data from surface soils are often neglected or questioned when prospecting for ore deposits within active mining districts due to the “background noise” produced by anthropogenic pollution derived from mining activity. Large datasets on a national and international scale offer interesting possibilities to discover prospective zones. In the present work, data from the Geochemical Atlas of Castilla–La Mancha were treated in an area with an intense history of mining Hg, Pb, Zn, and Sb: the Almadén and Guadalmez synclines and the Alcudia Valley. The sampling grid was densified to adapt it to the scale of the main geological formations, and a cluster analysis was carried out to establish the relationships between the variables and a factor analysis to distinguish between geogenic and metallogenic factors. The results showed very high concentrations of some elements of prospective interest in local background areas: Hg (51 mg kg−1), Pb (1190 mg kg−1), and Sb (45 mg kg−1), with high variation coefficients. Cluster analysis unveiled a relationship between most of the local ore-forming metals (As, Sb, Hg, Pb, and Ag) with a clear correlation between Hg and organic matter, suggesting a notable contribution of Hg in soil. The factor analysis highlighted five factors, three geogenic and two ore-forming elements. Despite Hg being the main candidate to form a separate factor, its aerial deposition and a large number of outliers in the Almadén syncline contributed to integrating the element into a geogenic factor. Instead, factors F4 (Pb and Zn) and F5 (As and Sb) delimited the prospective areas in both synclines far from the known and the exploited mines. Some of these areas coincided with discovered mineralized zones, specifically in the area SE of a derelict Sb mine, confirming the usefulness of these datasets and statistical tools in areas with recent mining activity.

Geochemical and health risk assessment of potentially toxic trace elements and nitrate via groundwater in agro-ecosystem of alluvial plain Punjab, India

Sporadic rainfall and limited surface water sources have increased dependency on groundwater in semi-arid region of Punjab. The present paper is comprehensive study carried out in an intensive agricultural region of southwest Punjab to examine the quality and extent of contamination due to trace elements and nitrate in the aquifer system. Total 15 toxic elements are analyzed in groundwater samples (N = 129) covering both the shallow (<60 m) and deeper aquifers (>60 m). Elements such as As, B, Cd, Li, Mn, Pb, Sr, and Se exceed the prescribed limits. Overall, 68 and 13% of samples exceed the NO3 − permissible limit (45 ppm) in shallow and deep aquifers, respectively. Contaminants concentration increases toward groundwater flow direction, that is, from northeast to southwest possibly due to arid climatic conditions. Relatively, shallow aquifer is more contaminated than deeper aquifer due to fertilizers input and irrigation return flow. Drinking water quality indices (DWQI) reveal that groundwater is unfit for drinking at most locations. Further, health risk indicate that comparatively, children are at higher risk in terms of non-carcinogenic risk posed by nitrate, and higher carcinogenic risk for As, Cr, and Cd is seen in all age groups. Multivariate analysis reveals the influence of anthropogenic activities on NO3 −, Mn, Ni, and Zn levels, while geogenic factors control the, As and Mo concentrations. Present findings suggest regular monitoring of wells to lower the public health risk.

Surface water quality and geogenic process in the quillcayhuanca and shallap streams, huaraz-Peru

This research developed because, given the evidence of previous studies, it is necessary to determine the chemical quality of the water in the Quillcayhuanca and Shallap streams, which surround the city of Huaraz on its way to the Santa River, on the western slope of the Cordillera Blanca in Peru. In this sense, the investigated area is located at altitudes between 3524 m.a.s.l. and 4174 m.a.s.l. Twenty-four surface water samples were collected and analyzed for anions, metal, and total cations at the INGEMMET laboratory, Geological, Mining, and Metallurgical Institute of Peru. Likewise, geological mapping was carried out to identify the mineralized and chemically altered areas, evidencing the significant presence of sulfides (pyrite). The waters of the streams have been characterized as magnesium calcium sulfate, with SO4= anion contents of up to 181.10 mg/L in the Quillcayhuanca stream and 78.8 mg/L in the Shallap stream. Likewise, for both streams, an oxidized acid environment has been determined. The oldest stratigraphic unit corresponds to shales and sandstones of the Upper Jurassic Chicama Formation. The igneous rocks are made up mostly of granodiorites and tonalites corresponding to the Batholith of the Cordillera Blanca from the Neogene-Miocene. The Quaternary is represented by glacial, glacial fluvial, morainic and fluvial deposits. Regarding the chemical quality of the water, some elements exceed the environmental quality standards (ECA) for "Surface water intended for the production of drinking water" such as Al, Fe, and Mn. These elements are due to geogenic factors, given the presence of sulfides in the exposed rocks in the upper parts of the ravine plus the alteration of aluminosilicates in the exposed rocks.