Groundwater contamination by heavy metals (HMs) released by weathering and mineral dissolution of granite, gneisses, ultramafic, and basaltic rock composition causes human health concerns worldwide. This paper evaluated the heavy metals (HMs) concentrations and physicochemical variables of groundwater around enriched chromite mines of Malakand, Pakistan, with particular emphasis on water quality, hydro-geochemistry, spatial distribution, geochemical speciation, and human health impacts. To better understand the groundwater hydrogeochemical profile and HMs enrichment, groundwater samples were collected from the mining region (n = 35), non-mining region (n = 20), and chromite mines water (n = 5) and then analyzed using ICPMS (Agilent 7500 ICPMS). The ranges of concentrations in the mining, non-mining, and chromite mines water were 0.02–4.5, 0.02–2.3, and 5.8–6.0 mg/L for CR, 0.4–3.8, 0.05–3.6, and 3.2–5.8 mg/L for Ni, and 0.05–0.8, 0.05–0.8, and 0.6–1.2 mg/L for Mn. Geochemical speciation of groundwater variables such as OH⁻, H⁺, Cr⁺², Cr⁺³, Cr⁺⁶, Ni⁺², Mn⁺², and Mn⁺³ was assessed by atomic fluorescence spectrometry (AFS). Geochemical speciation determined the mobilization, reactivity, and toxicity of HMs in complex groundwater systems. Groundwater facies showed 45% CaHCO₃, 30% NaHCO₃, 23.4% NaCl, and 1.6% Ca-Mg-Cl water types. The noncarcinogenic and carcinogenic risk of HMs outlined via hazard quotient (HQ) and total hazard indices (THI) showed the following order: Ni > Cr > Mn. Thus, the HHRA model suggested that children are more vulnerable to HMs toxicity than adults. Hierarchical agglomerative cluster analysis (HACA) showed three distinct clusters, namely the least, moderately, and severely polluted clusters, which determined the severity of HMs contamination to be 66.67% overall. The PCAMLR and PMF receptor model suggested geogenic (minerals prospects), anthropogenic (industrial waste and chromite mining practices), and mixed (geogenic and anthropogenic) sources for groundwater contamination. The mineral phases of groundwater suggested saturation and undersaturation. Nemerow’s pollution index (NPI) values determined the unsuitability of groundwater for domestic purposes. The EC, turbidity, PO₄⁻³, Na⁺, Mg⁺², Ca⁺², Cr, Ni, and Mn exceeded the guidelines suggested by the World Health Organization (WHO). The HMs contamination and carcinogenic and non-carcinogenic health impacts of HMs showed that the groundwater is extremely unfit for drinking, agriculture, and domestic demands. Therefore, groundwater wells around the mining region need remedial measures. Thus, to overcome the enrichment of HMs in groundwater sources, sustainable management plans are needed to reduce health risks and ensure health safety.

Rainwater harvesting is an important step towards maximizing the water availability and land productivity in arid and semi-arid areas. The present study shows that the area of Ghazi Tehsil within Khyber Pakhtunkhwa Province, Pakistan, has great potential for rainwater harvesting due to its feasible climatic and topographic conditions. This area of 348 km² normally receives high rainfall annually, but, due to hilly terrain, the bulk of rainwater is lost in the runoff process. In order to enhance agricultural output for such a large area, the practice of rainwater harvesting is a sustainable and decisive approach. However, the selection of appropriate sites for rainwater harvesting on a large scale presents a critical challenge. In such areas, geospatial technology has proved very decisive in the identification of potential sites. In this study, we have used the HEC-GeoHMS tool (ArcGIS 9.3) to compute a curve number to represent the effects of rainfall against the hydrological soil group and landcover. Subsequently, the curve number was used as an input parameter in the soil conservation service runoff-curve number (SCS-CN) method to estimate surface runoff potential for different combinations of landcover and hydrological soil groups. It was observed that runoff was higher in mountainous areas and relatively low in plain areas. Finally, to identify the potential sites for rainwater harvesting, weighted overlay analysis-based related thematic map layers were further reclassified, and weights were assigned according to the technical guidelines of suggested international standards and under consideration of the study area’s topographic, hydrological, and climatic factors. As a result, about 20% of the area was found suitable, 52% less suitable, and 29% as not suitable. Furthermore, relative suitability was assigned to the results of suitable sites as an input for the identification of potential sites for different rainwater harvesting storage structures. These results show that 10% of the area was suitable for farm ponds, 5.74% for check dams, 21.5% for Nigarims, and 8.9% was found to be suitable for gully plugs. The comparison of our GIS-derived and field-based results spatially affirms that the analyzed results were agreeably overlaid in the context of spatial results for check dams, gully plugs, and Nigarims.

Soil pollution with heavy metals is continuously expanding with the rapid development of industrialisation and agriculture. The current study was aimed to determine the skewed nature and spatial distribution of soil heavy metals pollution in southern areas of Khyber Pakhtunkhawa. Fifty four soil samples were collected from the selected sites in southern districts and analysed for various soil physico-chemical and elemental concentrations. Various metals content, i.e. (Pb, Cd, Ni, Cr) was determined after acid digested through atomic absorption spectrophotometry. Results of the metals content in soil samples showed maximum values Pb (46.38), Cd(6.74), Ni(45.58), Cr(58.08) mg/kg, bluk density 1.46 g/cm³ and lowest pH value 6.53 for Lakki cement factory (LCF) site. Other parameters like soil electrical conductivity, total dissolved solids, percent porosity and soil urease activity also indicated higher values, i.e. 504 µs/cm, 250 mg/lit, 66% and 440.50 respectively. Positive Pearson correlation was found between metals concentration and soil physico-chemical properties except percent porosity and bulk density exhibited negative correlation. The multivariate statistical analysis of the data formed principal component that accounted for a total variance of 71.1%, on the basis of which metal contamination is traced to both geogenic and anthropogenic sources. Spatial distribution of the metals concentration showed higher concentration of Cd, Cr, Ni in Lakki cement factory (LCF) soil except Pb content that was observed maximum in Indus highway Karak (IHK) soil samples. Geoamccumulation index (I_geo) of the samples sites showed moderate contamination for studied metals with some uncontaminated sites showing a value of I_geo> 0. The study concludes a baseline data for metals concentration in the area, which can be used as a beacon for various strategic plannings regarding soil resource management in order to address the metals related health issues and environmental pollution.

Coronavirus disease (COVID-19) is a novel pandemic disease and was first identified in Wuhan, China, at the end of 2019. It has affected the whole world in a short period of time and declared as a sixth global health emergency as it disturbed routine of human being and all life activities. This study presents a review focusing on ongoing pandemic as a disaster that provided a way of opportunity for change towards potentially positive and negative impacts on the environment. The observed positive aspect for environment in the context of short time impacts are improvement in air quality due to reduction in greenhouse gas emission, noise, nitrogen dioxide, and particulate matter < = 2.5 μm experienced in countries including India, Pakistan, China, USA, Italy, France, Spain, and other European countries. The observed negative impacts include organic waste generation and its mismanagement due to lockdown, non-functioning of waste recycling plants, municipal activities, and medical waste of materials used for personnel care protection. The study is explored through image data available from European Space Agency and National Aeronautical Space Agency to assess positive and negative impacts on environment. With available environmental observations, this review aims to assess impacts of current pandemic on environment focusing on some major Asian, European countries and USA. The present approach enabled determining changes with positive and negative effects on the environment. The observed assessments provide spatiotemporal based support for theoretical perspective that pandemic disasters can provide a way of opportunity for positive change in environment with slight negative environmental change.