Geochemical analyses of bottom sediment from rivers flowing through Orissa State, India indicated... more Geochemical analyses of bottom sediment from rivers flowing through Orissa State, India indicated that trace element concentrations were extremely variable, and commonly higher than crustal abundance. The highest elemental concentrations were associated with the Brahmani River, followed by the Baitarani and Mahanadi Rivers. Although all three rivers drain similar geology, the Brahmani River catchment is heavily industrialized, and sediment collected downstream from industry confirms that anthropogenic activity influenced its chemical composition. A similar pattern was observed in sediments collected downstream from towns in the Mahanadi and Baitarani catchments. In both examples, the clay size fraction was shown to be the most highly reactive component of the sediments. Comparisons between metal concentrations from the upper to lower stretches of the three river systems indicated no net accumulation downstream. Apparently, trace elements discharged into the river system tend to be short-lived in the water column, rapidly settling out or becoming adsorbed into the bottom sediment. Although for much of the year, the trace metals may remain locally incorporated as bottom sediment, during monsoonal episodes, where bedload transport can be significant, the effects of pollution may expand over regional distances.
Geochemical analyses of surface waters from rivers flowing through Orissa State, India, indicated... more Geochemical analyses of surface waters from rivers flowing through Orissa State, India, indicated that trace element concentrations were extremely variable and consistently higher than world river average. The Brahmani River was the most solute-rich river studied, followed by the Baitarani and Mahanadi Rivers. Although all three rivers drain similar geology, the Brahmani River catchment is heavily industrialized, and water samples collected upstream and downstream from industries indicated that anthropogenic activity directly influenced its chemical composition. Samples collected from several towns, in all three river systems, did not invariably show similar patterns, with various elements having higher dissolved concentrations upstream. Because the concentration of total solids increased downstream, this implied that some components of the sewage had effectively sequestered available elements from solution and converted them to particulate material. Although the impact of pollution is clearly recognizable in water samples collected in proximity to the anthropogenic source, there are only slight elemental accumulations in the lower reaches of the Mahanadi River, with no accumulation in the Brahmani River. Apparently for these large rivers, discharged effluent becomes rapidly diluted, while complexation and sedimentation further removes trace elements from the water column. However, in the less voluminous Baitarani River, elementar enrichment near the river's mouth suggests that in this secondary Fig. 1 Location of study areas and sample sites river, where dilution effects are less, the concerns over regional water quality may be more prevalent.
Geochemical and geoelectrical investigations were carried out around a hot spring near village Si... more Geochemical and geoelectrical investigations were carried out around a hot spring near village Singhpur, Nayagarh District of Orissa to delineate the extent of fluoride contamination in groundwater. Fluoride concentration is observed to be very high in both hot spring and groundwater of Singhpur village compared with surrounding ones. Vertical electrical sounding (VES) studies in the area reveal the presence of two to four prominent litho units. The weathered and fractured litho units constitute the main aquifer system. Spatial distribution of apparent resistivities at different electrode spacing indicates the presence of a low apparent resistivity zone encompassing the hot spring and the villages with fluoride contamination such as Singhpur and Sagaragan. Fluoride concentrations of groundwater and hot spring water show an inverse relation with the apparent resistivity of the formation at different electrode spacing. The results of geoelectric soundings, coupled with the geochemical studies and a well inventory, confirm that the fluoride contamination of groundwater is mainly due to venting of thermal water into the regional aquifer system through the fractured and weathered rocks.
The study has investigated the levels of metal contamination in groundwater due to particulate ma... more The study has investigated the levels of metal contamination in groundwater due to particulate matter fallout and leaching from ash pond and assigned contamination indices for the adjacent localities around an ash disposal site with application of geographic information systems (GIS). Fe, Ba, Cu, Mn, S, Pb, V, and Zn were found to be the major contaminants in groundwater. Enrichment factors (EF) of these elements with respect to the United States Environmental Protection Agency (USEPA) maximum contaminant levels show high values for Mn, Fe, and Pb in groundwater. The zone of attenuation for Ba, Fe, Cu, Mn, S, and Zn in groundwater is about 600-900 m from the ash pond, while Pb did not show any significant attenuation even at a distance of 1200 m. Tube wells around Rankasingha and Kukurhanga villages are most contaminated whereas open wells of Lachhmanpur, Kaniapada, and Kurudul villages showed higher degrees of contamination.
Communications in Soil Science and Plant Analysis, 2003
Effect of addition of municipal solid waste compost (MSWC) on cobalt (Co) and nickel (Ni) content... more Effect of addition of municipal solid waste compost (MSWC) on cobalt (Co) and nickel (Ni) contents of submerged rice paddies were studied. A sequential extraction method was used to determine the metal (Co and Ni) fractions in MSWC and cow dung manure (CDM). Both metals were significantly bound to the organic matter and Fe and Mn oxides in MSWC and
The importance of the use of potassium in agriculture is increasing in South Asia for making most... more The importance of the use of potassium in agriculture is increasing in South Asia for making most productive use of the nutrient in terms of economic returns. Nutrient supply traditionally by cattle manure is constrained by its insufficient availability. Municipal waste compost may be an alternative source of nutrient supplements. Field experiments were conducted at the Experimental Farm of Calcutta University, West Bengal, India during the wet seasons of 1997, 1998 and 1999 on flooded lowland rice. Potassium fractions in municipal waste compost and cattle manure were determined by sequential extraction and also the potassium uptake by rice to compare the effectiveness of municipal waste compost with traditional manure. Potassium was significantly bound to the organic matter in municipal waste compost. Potassium uptake by rice grain and straw increased significantly with the combined application of organics and fertilizers and it was higher in grain than in straw. Water-soluble and non-exchangeable potassium contents of municipal waste compost and cattle manure were highly correlated with the uptake of potassium by straw and grain. Exchangeable and residual potassium were also significantly correlated with the uptake of potassium by straw and grain of rice. Much higher uptake of K in rice straw and rain resulted from applying the manures in conjunction with fertilizers than when applied singly.
The influence of metals, Cd, Cr, Cu, Ni, Pb and Zn, on the microbial biomass and enzyme activitie... more The influence of metals, Cd, Cr, Cu, Ni, Pb and Zn, on the microbial biomass and enzyme activities of an amended acid lateritic soil were investigated under field conditions receiving a onetime application of 52 t ha)1 of sludge, coal ash and their mixtures at 1:3, 1:1 and 3:1 proportions, and including control and chemical fertilizer treatment at crop-specific recommended doses. Paddies and peanuts were grown in the experimental plots and soil was sampled twice after 6 months and 1 year after amendment application. The heavy metals in the soil were fractionated using sequential extraction and the increments in their concentrations in amended soil with respect to the control were determined. Concentrations of Cd, Ni and Zn were determined to have increased in their mobile fractions and were more pronounced in soil collected during the second sampling, which was associated with a decrease in soil organic carbon. The size of the microbial biomass carbon and the soil enzyme activities increased with the addition of an amendment and was highest at equal proportions of coal ash and sludge. Further increase in the proportion of sludge resulted in a significant decrease in biomass carbon. Simple correlation revealed significant and strong negative relations of mobile fractions of Cd and Ni with the ratio between microbial biomass C and organic carbon in soil, while the organic carbon content and the pH were positively correlated. The microbial activities were determined to be sensitive to the concentrations of some heavy metals in mobile fractions and therefore indicated possibilities of being useful as indicators for evaluation of toxic effects of sludge-borne metals on soil organisms.
Laboratory batch experiments were carried out to study the competitive sorption behavior of metal... more Laboratory batch experiments were carried out to study the competitive sorption behavior of metals in three types of Indian soils, differing in their physicochemical properties: acid laterite (SL1), red alfisol (SL2) and black vertisol (SL3) treated with different proportions of ...
Geochemical analyses of bottom sediment from rivers flowing through Orissa State, India indicated... more Geochemical analyses of bottom sediment from rivers flowing through Orissa State, India indicated that trace element concentrations were extremely variable, and commonly higher than crustal abundance. The highest elemental concentrations were associated with the Brahmani River, followed by the Baitarani and Mahanadi Rivers. Although all three rivers drain similar geology, the Brahmani River catchment is heavily industrialized, and sediment collected downstream from industry confirms that anthropogenic activity influenced its chemical composition. A similar pattern was observed in sediments collected downstream from towns in the Mahanadi and Baitarani catchments. In both examples, the clay size fraction was shown to be the most highly reactive component of the sediments. Comparisons between metal concentrations from the upper to lower stretches of the three river systems indicated no net accumulation downstream. Apparently, trace elements discharged into the river system tend to be short-lived in the water column, rapidly settling out or becoming adsorbed into the bottom sediment. Although for much of the year, the trace metals may remain locally incorporated as bottom sediment, during monsoonal episodes, where bedload transport can be significant, the effects of pollution may expand over regional distances.
Geochemical analyses of surface waters from rivers flowing through Orissa State, India, indicated... more Geochemical analyses of surface waters from rivers flowing through Orissa State, India, indicated that trace element concentrations were extremely variable and consistently higher than world river average. The Brahmani River was the most solute-rich river studied, followed by the Baitarani and Mahanadi Rivers. Although all three rivers drain similar geology, the Brahmani River catchment is heavily industrialized, and water samples collected upstream and downstream from industries indicated that anthropogenic activity directly influenced its chemical composition. Samples collected from several towns, in all three river systems, did not invariably show similar patterns, with various elements having higher dissolved concentrations upstream. Because the concentration of total solids increased downstream, this implied that some components of the sewage had effectively sequestered available elements from solution and converted them to particulate material. Although the impact of pollution is clearly recognizable in water samples collected in proximity to the anthropogenic source, there are only slight elemental accumulations in the lower reaches of the Mahanadi River, with no accumulation in the Brahmani River. Apparently for these large rivers, discharged effluent becomes rapidly diluted, while complexation and sedimentation further removes trace elements from the water column. However, in the less voluminous Baitarani River, elementar enrichment near the river's mouth suggests that in this secondary Fig. 1 Location of study areas and sample sites river, where dilution effects are less, the concerns over regional water quality may be more prevalent.
Geochemical and geoelectrical investigations were carried out around a hot spring near village Si... more Geochemical and geoelectrical investigations were carried out around a hot spring near village Singhpur, Nayagarh District of Orissa to delineate the extent of fluoride contamination in groundwater. Fluoride concentration is observed to be very high in both hot spring and groundwater of Singhpur village compared with surrounding ones. Vertical electrical sounding (VES) studies in the area reveal the presence of two to four prominent litho units. The weathered and fractured litho units constitute the main aquifer system. Spatial distribution of apparent resistivities at different electrode spacing indicates the presence of a low apparent resistivity zone encompassing the hot spring and the villages with fluoride contamination such as Singhpur and Sagaragan. Fluoride concentrations of groundwater and hot spring water show an inverse relation with the apparent resistivity of the formation at different electrode spacing. The results of geoelectric soundings, coupled with the geochemical studies and a well inventory, confirm that the fluoride contamination of groundwater is mainly due to venting of thermal water into the regional aquifer system through the fractured and weathered rocks.
The study has investigated the levels of metal contamination in groundwater due to particulate ma... more The study has investigated the levels of metal contamination in groundwater due to particulate matter fallout and leaching from ash pond and assigned contamination indices for the adjacent localities around an ash disposal site with application of geographic information systems (GIS). Fe, Ba, Cu, Mn, S, Pb, V, and Zn were found to be the major contaminants in groundwater. Enrichment factors (EF) of these elements with respect to the United States Environmental Protection Agency (USEPA) maximum contaminant levels show high values for Mn, Fe, and Pb in groundwater. The zone of attenuation for Ba, Fe, Cu, Mn, S, and Zn in groundwater is about 600-900 m from the ash pond, while Pb did not show any significant attenuation even at a distance of 1200 m. Tube wells around Rankasingha and Kukurhanga villages are most contaminated whereas open wells of Lachhmanpur, Kaniapada, and Kurudul villages showed higher degrees of contamination.
Communications in Soil Science and Plant Analysis, 2003
Effect of addition of municipal solid waste compost (MSWC) on cobalt (Co) and nickel (Ni) content... more Effect of addition of municipal solid waste compost (MSWC) on cobalt (Co) and nickel (Ni) contents of submerged rice paddies were studied. A sequential extraction method was used to determine the metal (Co and Ni) fractions in MSWC and cow dung manure (CDM). Both metals were significantly bound to the organic matter and Fe and Mn oxides in MSWC and
The importance of the use of potassium in agriculture is increasing in South Asia for making most... more The importance of the use of potassium in agriculture is increasing in South Asia for making most productive use of the nutrient in terms of economic returns. Nutrient supply traditionally by cattle manure is constrained by its insufficient availability. Municipal waste compost may be an alternative source of nutrient supplements. Field experiments were conducted at the Experimental Farm of Calcutta University, West Bengal, India during the wet seasons of 1997, 1998 and 1999 on flooded lowland rice. Potassium fractions in municipal waste compost and cattle manure were determined by sequential extraction and also the potassium uptake by rice to compare the effectiveness of municipal waste compost with traditional manure. Potassium was significantly bound to the organic matter in municipal waste compost. Potassium uptake by rice grain and straw increased significantly with the combined application of organics and fertilizers and it was higher in grain than in straw. Water-soluble and non-exchangeable potassium contents of municipal waste compost and cattle manure were highly correlated with the uptake of potassium by straw and grain. Exchangeable and residual potassium were also significantly correlated with the uptake of potassium by straw and grain of rice. Much higher uptake of K in rice straw and rain resulted from applying the manures in conjunction with fertilizers than when applied singly.
The influence of metals, Cd, Cr, Cu, Ni, Pb and Zn, on the microbial biomass and enzyme activitie... more The influence of metals, Cd, Cr, Cu, Ni, Pb and Zn, on the microbial biomass and enzyme activities of an amended acid lateritic soil were investigated under field conditions receiving a onetime application of 52 t ha)1 of sludge, coal ash and their mixtures at 1:3, 1:1 and 3:1 proportions, and including control and chemical fertilizer treatment at crop-specific recommended doses. Paddies and peanuts were grown in the experimental plots and soil was sampled twice after 6 months and 1 year after amendment application. The heavy metals in the soil were fractionated using sequential extraction and the increments in their concentrations in amended soil with respect to the control were determined. Concentrations of Cd, Ni and Zn were determined to have increased in their mobile fractions and were more pronounced in soil collected during the second sampling, which was associated with a decrease in soil organic carbon. The size of the microbial biomass carbon and the soil enzyme activities increased with the addition of an amendment and was highest at equal proportions of coal ash and sludge. Further increase in the proportion of sludge resulted in a significant decrease in biomass carbon. Simple correlation revealed significant and strong negative relations of mobile fractions of Cd and Ni with the ratio between microbial biomass C and organic carbon in soil, while the organic carbon content and the pH were positively correlated. The microbial activities were determined to be sensitive to the concentrations of some heavy metals in mobile fractions and therefore indicated possibilities of being useful as indicators for evaluation of toxic effects of sludge-borne metals on soil organisms.
Laboratory batch experiments were carried out to study the competitive sorption behavior of metal... more Laboratory batch experiments were carried out to study the competitive sorption behavior of metals in three types of Indian soils, differing in their physicochemical properties: acid laterite (SL1), red alfisol (SL2) and black vertisol (SL3) treated with different proportions of ...
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