Groundwater Quality Monitoring in Shallow and Deep Aquifers in Saidabad Tahsil Area, Mathura District, India

Water availability in arid regions is both sporadic and highly variable in quantity. If the water quality shows large variations of salinity and concentration of other chemical constituents with depth and time span, it has considerable effect on the entire hydrological set up of the area. In the Saidabad tahsil area, the deep aquifers that supply water to borewells in the alluvial plain of the Mathura region, Uttar Pradesh, have higher salinity than those of the dugwells from the shallow aquifers. The excessive drilling of tubewells and high yield tubewells are resulting in deterioration of water quality of the shallow aquifers. On the contrary, the chemical constituents such as, Na⁺, K ⁺, Cl ^-, andHCO ₃ ^- show higher concentration in shallow aquifers than deep aquifers. A study carried out to monitor water quality in this region reveals that the groundwater quality varies with depth and time span in shallow and deep aquifers. Factors controlling variations in salinity and concentration of chemical constituents of the water in the two types of aquifers are discussed. The relative merits of the shallow water for potability are pointed out with respect to salinity concentrations and public health.     

Bio-concentration of chromium—an <Emphasis Type="Italic">in situ</Emphasis> phytoremediation study at South Kaliapani chromite mining area of Orissa,India

Mine waste water at South Kaliapani usually contains toxic levels of hexavalent Cr(VI). The present in situ study was conducted at South Kaliapani chromite mine area in Orissa state, India, to assess the phytoremediation ability of three plants, namely, rice (Oryza sativa L.), paragrass (Brachiaria mutica), and an aquatic weed (Eichhornia crassipes), in attenuating Cr(VI) from mine waste water and to correlate the bio-concentration factors (BCF) of Cr. Water hyacinth (E. crassipes) showed 24% to 54% reduction whereas paragrass (B. mutica) was able to reduce 18% to 33% of Cr(VI) from mine water. This reduction was studied over a period of 100 days of plant growth. The reduction was observed through a passage of a sum total of 2,000 sq. ft. cultivated plots and ponds separately. Reduction in Cr(VI) content in mine water varies with plant age as well as with the distance of passage. Cr accumulation and BCF values increased with high soil Cr levels as well as the age of plants. High BCF and transportation index (Ti) values, i.e., 10,924 and 32.09, respectively, were noted for water hyacinth. The Ti values indicated that the root-to-shoot translocation of Cr was very high after 100 days of growth. The total accumulation rate was maximum (8.29 mg Cr kg dry biomass^− 1 day ^− 1) in paragrass. The BCF values for roots were noted to be higher than those of leaves, stems, and grains of the 125-day-old plants. Hence, paragrass and water hyacinth may be used as tools of phytoremediation to combat the problem of in situ Cr contamination.     

Hydrogeochemical processes controlling the high fluoride concentration in groundwater: a case study at the Boden block area,Orissa, India

The present investigation reports the assessment of hydrochemical/geochemical processes controlling the concentration of fluoride in groundwater of a village in India (Boden block, Orissa). Boden block is one of the severely affected fluoride-contaminated areas in the state of Orissa (India). The sampling and subsequent analysis of water samples of the study area was carried out following standard prescribed methods. The results of the analysis indicate that 36.60% groundwater F⁻ concentration exceeds the limit prescribed by the World Health Organization for drinking water. The rock interaction with groundwater containing high concentration of HCO₃⁻ and Na⁺ at a higher pH value of the medium could be one of the important reasons for the release of F⁻ from the aquatic matrix into groundwater. Geochemical classification of groundwater based on Chadha rectangular diagram shows that most of the groundwater samples having fluoride concentration more than 1.5 mg L⁻¹ belongs to the Na-K-HCO₃ type. The saturation index values evaluated for the groundwater of the study area indicated that it is oversaturated with respect to calcite, whereas the same is undersaturated with respect to fluorite content. The deficiency of calcium ion concentration in the groundwater from calcite precipitation favors fluorite dissolution leading to excess of fluoride concentration. The risk index was calculated as a function of fluoride level in drinking water and morbidity of fluorosis categorizes high risk for villages of Amera and Karlakote panchayat of Boden block.     

Physico-chemical assessment of paper mill effluent and its heavy metal remediation using aquatic macrophytes—a case study at JK Paper mill, Rayagada, India

The present investigation aims to assess the phytoremediation potential of six aquatic macrophytes, viz. Eichhornia crassipes, Hydrilla verticillata, Jussiaea repens, Lemna minor, Pistia stratiotes and Trapa natans grown in paper mill effluent of JK Paper mill of Rayagada, Orissa, for remediation of heavy metals. The experiment was designed in pot culture experiments. Assessment of physico-chemical parameters of paper mill effluent showed significant decrease in pH, conductivity, total dissolved solids, total suspended solids, chlorine, sulphur, biological and chemical oxygen demand after growth of macrophytes for 20 days. Phytoremediation ability of these aquatic macrophytic species for copper (Cu) and mercury (Hg) was indicated by assessing the decrease in the levels of heavy metals from effluent water. Maximum reduction (66.5 %) in Hg content of untreated paper mill effluent was observed using L. minor followed by T. natans (64.8 %). L. minor showed highest reduction (71.4 %) of Cu content from effluent water followed by E. crassipes (63.6 %). Phytoextraction potential of L. minor was remarkable for Hg and Cu, and bioaccumulation was evident from bioconcentration factor values, i.e. 0.59 and 0.70, respectively. The present phytoremediation approach was considered more effective than conventional chemical treatment method for removing toxic contaminants from paper mill effluent.     

Concentrations of heavy metals and aquatic macrophytes of Govind Ballabh Pant Sagar an anthropogenic lake affected by coal mining effluent

Five heavy metals Cu, Cd, Mn, Pb and Hg were found in high concentration from three sampling sites located in Asia’s largest anthropogenic lake Govind Ballabh Pant GBP Sagar. Concentrations of these heavy metals were measured in Water, bottom sediment and in different parts of the aquatic macrophytes collected from the reservoir. Plants collected from the lake were Eichhornia crassipes, Azolla pinnata, Lemna minor, Spirodela polyrrhiza, Potamogeton pectinatus, Marsilea quadrifolia, Pistia stratiotes, Ipomea aquqtica, Potamogeton crispus, Hydrilla verticillata and Aponogeton natans. These plants have shown the high concentrations of Cu, Cd, Mn, Pb and Hg in their different parts due to bioaccumulation. In general plant roots exhibited higher concentrations of heavy metals than corresponding sediments. A comparison between different morphological tissues of the sampled plants reveled the metal concentration in following order roots > leaves. Analyses of bottom sediment indicated the higher concentrations of Cd, Mn, Cu and Pb. Strong positive correlations were obtained between the metals in water and in plants as well as between metal in sediment and in plants. Indicating the potential of these plants for pollution monitoring of these metals.     

Climate change and the Western Himalayan community: Exploring the local perspective through food choices

The local belief systems are crucial for climate change adaptation. Even climate experts are unanimous about the fundamental association between local beliefs and climate change adaptation strategies. However, the local perspective is missing from the significant policy dialog platforms. The local beliefs can potentially serve as both objective and psychological refuge for local societies during climate-related emergencies. Similarly, only limited studies have acknowledged the significance of local food choices, providing a model for global responses to climate change. The objective of the study is (i) to explore the local community’s insights and awareness of climate change and (ii) to assess the impact on local food choices affecting their food security in the face of climate change in the Western Himalayan Region, India. The study is based on 210 in-depth household interviews and surveys in 10 villages of Uttarakhand, India. The exploratory factor and thematic analysis results highlight the significance of local perception of climatic variabilities, food choices, and beliefs in climate change adaptation policies. Hence, the current study’s outcomes emphasize on the integration and promotion of both scientific methods and local knowledge for inclusive climate change adaptation and food security policies in the Himalayan Region.     

Microwave synthesis,characterization, and bio-efficacy of novel halogenated Schiff bases

A new series of halogenated Schiff bases was synthesized by the condensation of 5-fluoro-2-hydroxy acetophenone and 3,5-dichloro-2-hydroxy acetophenone with different alkyl amines, namely propyl, pentyl, hexyl, heptyl, octyl, nonyl, dodecyl, tetradecyl, hexadecyl, and octadecyl amines, under microwave irradiation. Newly formed molecules were characterized by Infrared and nuclear magnetic resonance (¹H NMR and ¹³C NMR) spectroscopic techniques. Further, the Schiff bases were screened for antifungal bioassay, and the results showed potential fungicidal activity against two very important plant infecting fungi, viz. Rhizoctonia solani and Sclerotium rolfsii. Among the screened compounds, 2,4-dichloro-2-[1-(propylimino)ethyl]phenol was found to be the most active compound against both R. solani (ED₅₀ 8.02 mg L^?1) and S. rolfsii (ED₅₀ 21.51 mg L^?1) followed by 2,4-dichloro-2-[1-(pentylimino) ethyl]phenol (ED₅₀ 13.02 and 29.57 mg L^?1, respectively). The synthesized compounds were also screened for antioxidant activity by 2,2-diphenyl-1-picrylhydrazyl (DPPH)-free radical scavenging technique. All the compounds showed very low to moderate activity as compared with Gallic acid.     

Altitude distribution of aerosols over Southeast Arabian Sea coast during pre-monsoon season: Elevated layers,long-range transport and atmospheric radiative heating

Every year, during the pre-monsoon period (March–May), a pronounced increase in aerosol optical depth (AOD) is observed over the eastern Arabian Sea, which is attributed to the transport of continental aerosols. This paper presents the altitude distribution of tropospheric aerosols, characteristics of elevated aerosol layers and aerosol radiative heating of the atmosphere during the pre-monsoon season over Trivandrum (8.5°N, 77°E), a station located at the southwest coast of Indian peninsula which is covered by the eastern Arabian Sea plume. Altitude profiles of aerosol backscatter coefficient (β_a) and linear depolarization ratio (LDR) reveal two distinct aerosol layers persisting between 0–2 km and 2–4 km. The layer at 2–4 km, which contributes about 25% of the AOD during polluted conditions, contains significant amount of non-spherical aerosols. This layer is prominent only when the advection of dry airmass occurs from the northern parts of the Indian subcontinent and northern Arabian Sea. Role of long-range transport in the development of this aerosol layer is further confirmed using latitude–altitude cross-section of β_a observed by CALIPSO. Aerosol content in the layer below 2 km is large when advection of air occurs from the north and east Arabian Sea and is significantly small when it occurs from the southwest Arabian Sea or Indian Ocean. During the highly polluted conditions, aerosols tend to increase the diurnal mean atmospheric radiative heating rate by ～0.8 K day^?1 at 500 m and 0.3 K day^?1 at 3 km, which are about 80% and 30% of the respective radiative heating in the aerosol-free atmosphere.     

Cytotoxic effect of plant extract-based nanoparticles on cancerous cells: a review

Environmental Chemistry Letters - Cancer is one of the most fatal diseases causing deaths of millions of people worldwide. Since actual cancer treatments are rarely efficient and often toxic, there...