Srimanta Gupta

Metal accumulation and its effects in relation to biochemical response of vegetables irrigated with metal contaminated water and wastewater.

Agricultural application of metal contaminated water resulted in elevated concentrations of metals in irrigated soil and vegetables. Metal enrichment in irrigated soil is in the sequence of Cr>Fe>Pb>Mn>Zn>Cu>Cd. High metal translocation was observed from soil to plants with varied accumulation pattern in different species. Fe, Mn, Cu, Zn, Cr showed higher translocation to the aerial parts, while Cd, Pb exhibits their restricted mobility and concentrated in roots and stems. Hyperaccumulation of metals in vegetative parts resulted significant decrease (p<0.05) in total chlorophyll and soluble sugars, with elevated (p<0.05) protein and proline content in cultivated vegetables. Oxidative stress due to high metal concentrations significantly induced (p<0.05) the antioxidant-enzyme activity. Peroxidase (52-206%) and catalase (40-106%) activity was noticeably higher in all the examined species, while enhanced activity of ascorbate peroxidase (70-78%) was observed in pea and spinach.

Impact of industrial waste effluents on river Damodar adjacent to Durgapur industrial complex, West Bengal, India.

The present study deals with the characterization of industrial effluents released from various industries and distribution of heavy metals in effluent discharge channel and its impact on the river Damodar. The effluent of tamlanala, a natural storm water channel, is extensively used for irrigation for growing vegetables in and around the study area. The heavy metals in water of the study area are in the order of Fe > Mn > Pb > Cd and sediments follow similar trends too. The enrichment of heavy metals in the sediments are in the order of Cd (39.904) > Pb (33.156) > Mn (0.164) > Fe (0.013). The geoaccumulation index values reveal effluent channel is subjected to moderate to high pollution with respect to Cd (4.733) and Pb (4.466). The analyzed data for enrichment factors and the pollution load index (1.305) show that effluent channels have suffered from significant heavy metal contamination following industrialization and urbanization. Compared to baseline values, the surface sediment layers show high enrichment across the channel and at its discharge point. The factor analysis reveals three factors—industrial sources, surface runoff inputs, and background lithogenic factors which clarify the observed variance of the environmental variables. Metal pollution assessment of sediments suggests that pollution from the heavy metals observed is high in the tamlanala which in turn affects the downstream of the river system.

Effects of metal stress on biochemical response of some aquatic macrophytes growing along an industrial waste discharge channel

Abstract The present research work focused on the metal translocation in the soil-plant system and subsequent metal stress on biochemical response of aquatic macrophytes growing along an industrial waste discharge channel. The bottom sediment of the effluent channel is highly contaminated with metals. High transfer factor (TF) for most of the metals indicated higher metal uptake by aquatic macrophytes of which Typha sp. was found to be the most suitable. Average TF was in the order of Fe (4.82) > Mn (3.91) > Cu (3.59) > Cd (2.29) > Zn (2.22) > Cr (1.83) > Pb (1.80). Hyper accumulation of metals within plants resulted in significant reductions in total chlorophyll, soluble sugar with an increase in protein and proline content. The investigation also demonstrated that exposure to high concentrations on metals resulted in enhanced activity of catalase (61.82–90.91%) and peroxidase (37.08–70.23%) in all examined macrophytes with a reduced (27.58–43.4%) or unchanged ascorbate peroxidase activity depending on plant species.

Temporal changes and depth wise variations in pit pond hydrochemistry contaminated with industrial effluents with special emphasis on metal distribution in water-sediment system.

The investigation showed pronounced temporal and vertical variations of pit lake-water chemistry contaminated with industrial effluents. An intermixing layer of few meters at a depth of 5-8 m usually separates an upper oxic epilimnion with alkaline pH from deeper sub-oxic/anoxic zone with relatively lower pH. Metal concentrations were in higher magnitude at anoxic zone in comparison to surface layer. Most of the parameters including metals showed higher concentrations during summer, while least concentrations were observed during monsoon. In shallow sediments, metals were mainly in insoluble-residual form, while redox metals were fractionated as oxihydroxide-reducible form. Geoaccumulation of metals in bottom sediments were Fe>Cr>Pb>Cu>Cd>Mn>Zn. Toxicity assessment showed that pit pond water is highly contaminated (C(d)=7.52) and moderate pollution load (PLI=2.272) in shallow sediments, with metal evaluation index (HEI) value of 11.08 and 15.91 respectively.

Application of geospatial technologies for multi-hazard mapping and characterization of associated risk at local scale

ABSTRACT In this study multi-hazard risk assessment is carried out in Arithang ward, one of the major wards within Gangtok Municipal Corporation, with the objectives of (a) landslide and earthquake hazard mapping of Gangtok city with analytical hierarchy process (b) vulnerability mapping in Arithang ward and (c) semiquantitative and semiqualitative risk analysis. Landslide hazard zonation (LHZ) depicts that very high and high hazard zone occupies 6% and 17% of the Gangtok city whereas 60% and 18% of area falls under medium and low hazard category respectively. With respect to seismic hazard susceptibility 13% and 22% of area falls under very high and high category respectively. Semiquantitative risk analysis reveals that majority of the residential buildings are concentrated in low earthquake and landslide hazard zone followed by 39% and 35% within medium class. Only 0.6% and 7% of residential buildings are found in high earthquake and landslide hazard zones. Bamboo and wood made buildings are found to cluster within very high class of landslide hazard. About 61% of multistoried buildings are placed within low zone of LHZ. Risk analysis reveals that buildings at the eastern and western part of Arithang ward come under high risk with respect to earthquake and landslide.

Comparative evaluation of various approaches for landslide hazard zoning: a critical review in Indian perspectives

The progress of geospatial technique can help to minimise the losses as it emerges as a powerful technique for mapping landslide hazard zonation. Different researchers use different methods for landslide hazard assessment. But, there is not a single method which has been universally accepted for effective assessment of landslide hazard. In Indian subcontinent, 12.6% of land area is susceptible to landslide hazard and the estimated total economic damage due to landslide hazard is 4,500,000US

Study of particulate matters, heavy metals and gaseous pollutants at Gopalpur (23°29ʹ52.67ʺ N, 87°23ʹ46.08ʺE), a tropical industrial site in eastern India

. This review article represents the temporal development of different methodologies towards landslide hazard zonation up to a recent year and their advantages and disadvantages. The review indicates that mostly three methods i.e., knowledge driven, data driven and physical based method are followed among which, knowledge driven and bivariate analysis are mostly used during last decade but from the twenty-first century onwards multivariate statistical modelling is mostly popularised as it gives the most accurate result of landslide hazard zonation in comparison to other methods. Geospatial modelling of landslide susceptibility is useful for monitoring, mapping and formulating proper management plans that will be helpful for future landslide mitigation measures.

Comparative evaluation of water quality zonation within Dwarka River Basin, India

Air pollution has become an environmental problem of public concern worldwide. In the present study, the concentration of Particulate Matter (PM10), Oxides of Sulphur (SOx), Oxides of Nitrogen (NOx) and Ozone(O3) have been monitored from February 2013 to May 2013 over Gopalpur village in Durgapur situated at 23°29ʹ52.67ʺ N and 87°23ʹ46.08ʺE. Meteorological parameters like temperature, humidity, wind speed and wind direction were also simultaneously recorded over the chosen site.Various statistical tools have been used for the analysis of the obtained result. The data obtained from the field work have been compared with the secondary data obtained from Durgapur Station of Central Pollution Control Board (CPCB). The temporal variations of the concentrations of PM10, SOX, NOX and O3 have been explored and their relationships with different meteorological parameters have been identified. Concentration of PM10 ranged from 53.803 to 271.325μg/m 3 , with a mean value of 136.689± 54.873 μg/m 3 ,80% of the monitored data exceeded the National Ambient Air Quality Standards (NAAQS) for PM10 in the ambient atmosphere. The concentration of SOX over the site is found to lie between 14.219μg/m 3 to 390.041μg/m 3 , with a mean value of 104.601±103.860 μg/m 3 and 45 % of the total data exceeded the NAAQS for the concentration of SOX in the ambient air. The recorded concentration of NOX lies between 32.50 μg/m 3 112.79 μg/m 3 , with a mean value of 66.99± 21.63 μg/m 3 and 20% of the monitored data is found to exceed the NAAQS for NOX in the atmosphere. Record of eight hour (08:00:00 – 16:00:00 h, Indian Standard Time) ground level ozone concentration shows that O3 concentration gradually increases after sunrise (08:00:00 h) and reaches a high value during the noon (14:00:00 h – 15:00:00h). Detailed study shows that ozone has high positive correlation with temperature and high negative correlation with humidity. Atmospheric concentration of selected heavy metals including Lead (Pb), Copper (Cu), Manganese(Mn) and Cadmium (Cd) were also measured followed by the analysis of their probable sources. Wind rose has been constructed using WindRose PRO (Version 3.1.x). Industrial emission (Sponge Iron industries, Steel industries etc.), vehicular exhausts, open biomass burning, mining etc have been identified as the probable sources of the pollutants in the ambient atmosphere of Gopalpur.

Spatio-Temporal Variation and Futuristic Emission Scenario of Ambient Nitrogen Dioxide over an Urban Area of Eastern India Using GIS and Coupled AERMOD–WRF Model

ABSTRACT This study evaluates the thematic representation of drinking water quality of 211 habitations along the Dwarka River Basin (DRB), West Bengal, India. The dominant water type is Ca–Mg–HCO3. Statistical analysis of the spatial dataset indicates a clustering pattern (with a nearest-neighbour ratio of 0.368 and Z score of 29.774). Two different techniques, spatial interpolation of water quality index (WQI) and composite water quality index (WQIC) of physico-chemical constituents, were implemented to compare their performance. The WQIC indicates approximately 11.68% of the total study area is at non-permissible levels, whereas the normal WQI technique predicts about 1.64% of the area is in non-permissible zones. Spatial water quality zonation by means of the overlay technique was superior to the conventional WQI technique in precisely distinguishing the characteristics of the permissible area with respect to even a single WHO recommended water quality parameter.

CHAPTER 7:Fluoride Accumulation in Crops and Vegetables: Indian Perspectives

The present study focuses on the spatio-temporal variation of nitrogen dioxide (NO2) during June 2013 to May 2015 and its futuristic emission scenario over an urban area (Durgapur) of eastern India. The concentration of ambient NO2 shows seasonal as well as site specific characteristics. The site with high vehicular density (Muchipara) shows highest NO2 concentration followed by industrial site (DVC- DTPS Colony) and the residential site (B Zone), respectively. The seasonal variation of ambient NO2 over the study area is portrayed by means of Geographical Information System based Digital Elevation Model. Out of the total urban area under consideration (114.982 km2), the concentration of NO2 exceeded the National Ambient Air Quality Standard (NAAQS) permissible limit over an area of 5.000 km2, 0.786 km2 and 0.653 km2 in post monsoon, winter and pre monsoon, respectively. Wind rose diagrams, correlation and regression analyses show that meteorology plays a crucial role in dilution and dispersion of NO2 near the earth’s surface. Principal component analysis identifies vehicular source as the major source of NO2 in all the seasons over the urban region. Coupled AMS/EPA Regulatory Model (AERMOD)–Weather Research and Forecasting (WRF) model is used for predicting the concentration of NO2. Comparison of the observed and simulated data shows that the model overestimates the concentration of NO2 in all the seasons (except winter). The results show that coupled AERMOD–WRF model can overcome the unavailability of hourly surface as well as upper air meteorological data required for predicting the pollutant concentration, but improvement of emission inventory along with better understanding of the sinks and sources of ambient NO2 is essential for capturing the more realistic scenario.