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Heavy metals in sediments of the Yamura River (a tributary of the Ganges), India
Abstract
Yamuna River sediments are more enriched in metals than those of the Ganges and average Indian river sediments. Variation of metals in suspended, bed and core sediment are due to the varying proportions of grain size and mineral content.Iron, Mn and Pb show a preference for the oxide fraction, whereas Cu and Zn are predominant in organic and carbonate fractions of sediments. Of the total elemental content, 80% Mn, 78% Fe, 69% Pb, 67% Cu and 55% Zn are available in chemically mobile phases of the sediments. The high partition coefficient of metals with respect to Mn suggests similar chemical mobility and preferences for solid phases. River sediments in the vicinity of Delhi show an increase in sorption of metals downstream, consequently metals are retained in sediments.The high correlation coefficient and significant regression relation among the metals indicate their similar behaviour during transport. At Allahabad, the contribution of the Yamuna to the Ganges is 3200 t Pb year−1, 12 100 t Zn year−1 and 8500 t Cu year−1 in particulate form.
... The various categories of pollution as per Nemerow pollution index are: PI n ≤ 0.7 is unpolluted; 0.7 < PI n ≤ 1.0 is marginally polluted; 1.0 < PI n ≤ 2.0 is slightly polluted; 2.0 < PI n ≤ 3.0 is moderately polluted and PI n > 3.0 is severely polluted (Nemerow, 1991). The background concentrations of PTEs for calculating sediment indices were taken from Jha et al. (1990) for Fe, Cr, Ni, Cu, Zn and Pb, and from Ajmal et al. (1985) for Co and Cd. PTE concentration in deepest layers of cores (40-50 cm) collected in 1984 from Baghpat (Haryana) by Jha et al. (1990) along River Yamuna were considered, since, it was mostly unaffected by industrial pollution in 1980s. ...
... The background concentrations of PTEs for calculating sediment indices were taken from Jha et al. (1990) for Fe, Cr, Ni, Cu, Zn and Pb, and from Ajmal et al. (1985) for Co and Cd. PTE concentration in deepest layers of cores (40-50 cm) collected in 1984 from Baghpat (Haryana) by Jha et al. (1990) along River Yamuna were considered, since, it was mostly unaffected by industrial pollution in 1980s. For Co and Cd, the lowest reported value by Ajmal et al. (1985) in Yamuna sediments within Delhi were considered, since these are the earliest concentrations reported in the region. ...
... The average concentrations from lowest layers of cores collected in present study were not considered as background values since, rate of sedimentation in Yamuna floodplains of Delhi is ~2.6 cm y − 1 (average of rates calculated using 210 Pb and 137 Cs techniques by Saxena et al., 2002). Therefore, 45 to 50 cm depth in present cores corresponds to approximately 1998-99, which is ~15 years after sample collected by Ajmal et al. (1985) and ~ 8 years after Jha et al. (1990), and most probably show higher anthropogenic disturbances. ...
Environmental pollution of potentially toxic elements (PTEs) in urban wetlands is a serious concern due to their toxic, persisting nature and potential to bioaccumulate in aquatic food chain. A total of 34 samples (23 surface water, 8 surface sediment and 3 sediment cores) were analyzed for PTE concentrations in Okhla Bird Sanctuary. The surface waters are alkaline with pH ranging from 7.2 to 8.5, electrical conductivity ranging from 454 to 1557 μS cm−1. Hydrogeochemically, these are Na+-SO42− type in summer and Ca2+-Mg2+- SO42− type in winter season as per Piper classification. These show low compliance with recommended quality guidelines for Pb in winter (33%), and no compliance for Cd and Pb in summer season. As per heavy metal pollution index (HPI), high pollution in winter and critical pollution in summer season is observed. A sharp seasonal decline in the water quality indicates concentration of pollution load in summer. The surface sediments of Okhla Bird Sanctuary show severe PTE pollution as per nemerow pollution index (NPI). As per geoaccumulation index (Igeo), sediments are moderately to strongly contaminated for Pb. As per enrichment factor (EF), the sediments show moderately severe enrichment for Pb. On an average, the sediments show low-medium toxicity as per mean ERM quotient (MERM-Q) and moderate ecological risk as per potential ecological risk index (RI). As per hazard index (HI), in winter season, waters from the riverine and middle part show toxicity, whereas in summer, all the waters show toxicity for adults and children. Similarly, the surface sediments also show non-carcinogenic toxicity for children.
... The sediment composition and heavy metal concentrations found in the sediments of the exploratory well in Mathura are compared to the WHO limits for agricultural soils (Kinuthia et al. 2020;WHO 1993WHO , 2011, to the limits for pollution of well-head protection zones defined by the senate-department for urban development of Berlin (SVfS 2005) (which are widely applied in Germany) and to data from an aquifer sediment study at the RBF site Torgau by the river Elbe, Germany (Grischek et al. 1993) (Table 3.1). Further, Table 3.1 also includes a comparison of these concentrations to heavy metal concentrations determined for the Yamuna riverbed/bank sediments up to depths of 35-50 cm as reported in Ajmal et al. (1985) and Jha et al. (1990). A perusal of data in Table 3.1 indicates that the heavy metal concentrations in the sediments from the exploratory well are substantially lower compared to corresponding metal concentrations in the riverbed/bank sediment reported in previous studies (Ajmal et al. 1985;Jha et al. 1990). ...
... Further, Table 3.1 also includes a comparison of these concentrations to heavy metal concentrations determined for the Yamuna riverbed/bank sediments up to depths of 35-50 cm as reported in Ajmal et al. (1985) and Jha et al. (1990). A perusal of data in Table 3.1 indicates that the heavy metal concentrations in the sediments from the exploratory well are substantially lower compared to corresponding metal concentrations in the riverbed/bank sediment reported in previous studies (Ajmal et al. 1985;Jha et al. 1990). The upper 0-5 cm of sediment is relatively more abundant in heavy metal concentrations compared to the deeper sediment, with a general decrease of concentrations observed with increasing depth (Jha et al. 1990). ...
... A perusal of data in Table 3.1 indicates that the heavy metal concentrations in the sediments from the exploratory well are substantially lower compared to corresponding metal concentrations in the riverbed/bank sediment reported in previous studies (Ajmal et al. 1985;Jha et al. 1990). The upper 0-5 cm of sediment is relatively more abundant in heavy metal concentrations compared to the deeper sediment, with a general decrease of concentrations observed with increasing depth (Jha et al. 1990). It is not possible to observe a natural cycle of sedimentation because of cultivation within the dry river bed and excavation of riverbed sediments for construction in the non-monsoon season and redistribution of reworked sediments during monsoon floods (Jha et al. 1990). ...
Heavy metal contamination of sediments is often observed as a result of the expansion of industrial sectors and agro-economic systems, especially in developing regions. The high pollution of the river Yamuna in India, especially the substantial heavy metal contamination not only to the river but also increasingly to groundwater in Mathura and Agra regions is of concern for the production of drinking water. Consequently, this study focused on a prognosis of the risk of heavy metal contamination during the investigations for a new riverbank filtration (RBF) site in the cities of Mathura and Agra. Twenty sediment samples were taken at each site during the drilling of an exploratory well for RBF up to a depth of 30 m. The heavy metals As, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn were analysed in soil and aquifer sediments and water from the exploratory wells. Principal component analysis (PCA) was subsequently performed for the heavy metal concentrations in the soil and sediment samples. In general, the heavy metal concentrations found in the aquifer sediments were significantly lower compared to concentrations in riverbed material reported in literature, lower than WHO limits for agricultural soils (except Cd and Pb in Agra) and lower than values in other literature sources. While the heavy metal concentrations found in the exploratory well water in Mathura were generally found to be within the WHO drinking water guideline limits, the mean concentrations of Cd and Pb in the exploratory well in Agra significantly exceeded the WHO guideline values. The study concluded that the risk of leaching of heavy metals and consequent contamination to groundwater by the vertical movement of irrigation water is expected to be significantly greater compared to the movement of infiltrated river water through the riverbed during the RBF. Consequently, caution should be exercised when selecting flood-plain areas for new RBF sites that have been irrigated in the past with surface water impacted by heavy metals. The major sources of heavy metals identified by PCA were mainly natural and to a certain extent anthropogenic, especially in the upper layers of the soil/aquifer and is also indicative of a lesser risk of heavy metal contamination during RBF. Nevertheless, for RBF to be effective at new sites impacted by extreme environmental conditions, well-head and source-protection zones have to be implemented to avoid contamination of the aquifer from above ground anthropogenic activities. Furthermore, frequent water quality monitoring for not only heavy metals, but also other parameters in the RBF well(s), river and ambient (landward side) groundwater is important.
KeywordsHeavy metalsSedimentsRiverbank filtrationPrincipal component analysisDrinking water
... Sediments are important sinks for various pollutants like heavy metals and also play a significant role in the remobilization of contaminants in aquatic systems under favourable conditions and in interactions between water and sediment river sediments, therefore, are important sources for the assessment of man-made contamination in rivers. Several studies on the distribution of heavy metals in sediments of the river Ganges and its tributaries have been carried out different types of pollution (Ajmal et al., 1983;Subramanian et al., 1987;Saikia et al., 1988;Jha et al., 1990;Ansari et al., 2000;Dutta and Subramanian, 1998;Ramesh et al., 2000;, Singh et al. 2002 [3,77,65,41,7,22,63,66,68] have also reported that highly polluted sediments are adversely affecting the ecological functioning of rivers due to heavy metal mobilization from urban areas into biosphere. Therefore, in the present study, the distribution of heavy metals in both sediment and water of the river Gomti in different seasons at different sites in the Lucknow region have been investigated to initiate remedial measures to assess the pollution load. ...
... Sediments are important sinks for various pollutants like heavy metals and also play a significant role in the remobilization of contaminants in aquatic systems under favourable conditions and in interactions between water and sediment river sediments, therefore, are important sources for the assessment of man-made contamination in rivers. Several studies on the distribution of heavy metals in sediments of the river Ganges and its tributaries have been carried out different types of pollution (Ajmal et al., 1983;Subramanian et al., 1987;Saikia et al., 1988;Jha et al., 1990;Ansari et al., 2000;Dutta and Subramanian, 1998;Ramesh et al., 2000;, Singh et al. 2002 [3,77,65,41,7,22,63,66,68] have also reported that highly polluted sediments are adversely affecting the ecological functioning of rivers due to heavy metal mobilization from urban areas into biosphere. Therefore, in the present study, the distribution of heavy metals in both sediment and water of the river Gomti in different seasons at different sites in the Lucknow region have been investigated to initiate remedial measures to assess the pollution load. ...
The present study the selected heavy metals such as cadmium (Cd), chromium (Cr), lead (Pb), Manganese (Mn) and cooper (Cu) were determined in water, sediment and gill, liver, muscle of fish H. fossilis, the concentration of Cd, Cr, Pb, Cu Mn and Zn was observed 0.009, 0.056, 0.056, 0.058, 0.049, 0.883, 0.36 mg/l in river water and 3.38, 20.11, 81.53, 258.48, 258.48, 3.40 µg/g in sediment respectively. The heavy metals concentrations in the tissue of fish H. fossilis (µg/g dry weight), Cd 30.89, Cr 20.59, Pb 15.28, Cu 30.66 and Zn 26.67 µg/g in muscle, and the Cd 30.89, Pb 15.28, Cr 20.59, Cu 30.66 and Zn 32.42 in gills and Cd 34.44, Cr 18.00, Pb 17.34, Cu31.18 and Zn 58.44 µg/g in liver. The results showed that the liver appeared to the main heavy metals storage tissues, while the muscle of fish was lover accumulator compare than gill and liver. All the metals concentration exceeded the detection limits except than Mn. The results indicated that the selected fish does not feed directly without proper treatment of riverin ecosystem.
... On the basis of hydrological and ecological conditions, Yamuna has been classified into five segments that are Himalayan segment, Upper segment, Delhi segment, Eutrophicated segment and Diluted segment (Mishra, 2010). Several studies revealed that Yamuna is highly polluted river of India (Jha et al. 1990 Bhargava, 2006 Agarwal, 2009; Mishra, 2010). In Himachal Pradesh the disposal of untreated domestic and industrial wastes around Pontasahib, situated on the bank of Yamuna river, is aggravating the pollution problem. ...
... Yamuna in Haryana and Delhi states of India have indicated that river water possessed heavy metals. Textile, engineering, chemical, electrical and electronic industries contribute to metals deposition in river water. Several metals present in industrial effluents and municipal sewage around Haryana find their way into river Yamuna (Agarwal, 2009). Jha et al. (1990) Conclusion: The concentrations of dissolved metals (Cr, Cu, As, Cd, Ni, Pb, Mn, Zn and Fe) and non-metals (Mg, Ca and NO 3 ) in surface water of river Yamuna at different locations showed significant spatial variations. Irrespective of year and location of sampling, elemental concentrations differed from each other. When compared with t ...
The Yamuna river flows through Sirmour district in Himachal Pradesh (India) and receives domestic and industrial effluents from different villages and Ponta-sahib industrial hub situated on its bank. Ninety six surface water samples were collected from eight sites from the river during 2014 and 2015. Water quality with respect to 9 heavy metals (Cr, Cu, As, Cd, Ni, Pb, Mn, Zn & Fe) and 3 non-metals (NO 3 , Mg & Ca) was assessed for their variations, source apportionment and pollution indexing. Principal component analysis (PCA) outcome of different factors indicated natural and anthropogenic activities as contributing factors for metals profusion in the river. During 2014, three principal components were identified to be responsible for river water deterioration and accounted for 94.73% of overall total variance. PCA 1 in 2014 accounted for 70.16% of total variance and was characterized by high loading for Cr, Cu, NO 3 , As, Mn, Zn, Fe, Mg and Ca. River stretch during 2015 showed high pollution load and two principal components were identified responsible for the impairment of river water which accounted for 88.67% of the overall total variance. PCA 1 in 2015 accounted for 75.74% total variance and registered high loading for Cr, Cu, As, Ni, Mn, Zn, Fe, Mg and Ca. Based on pooled pollution index, in river water Cr, As and Zn were seriously (24.74), moderately (0.616) and slightly (0.380) polluting metals, respectively. Although river quality does not pose any serious threat to human health still various activities domiciled at downstream need to be discontinued to restore water quality.
... e attempts have been made to estimate the average chemical composition and heavy metal content of river sediments from the Indian Ž . sub-continent Subramanian et al., 1985aSubramanian et al., , 1987a . Recent geochemical studies on some river basins ŽBiksham and Ramesh et al., 1988Ramesh et al., , 1989Ramesh et al., , 1990Subramanian et al., 1988;Jha et . al., 1990 have yielded information which improve and update our knowledge of the elemental contribution of Indian rivers to the ocean. However, relative to their global importance, not enough research has been undertaken on the sediment chemistry of most of the Indian river basins. ...
... With regard to the sedimentation rates and vertical distribution of elements in the Indian river sediments, only a few studies have been Ž reported Sarin et al., 1979;Kalesha et al., 1980;Subramanian et al., 1985a;Ramesh et al., 1988Ramesh et al., , . Ž 1989Jha et al., 1990 . Only one of them Ramesh . ...
Suspended matter, surface and core sediments from the Cauvery River and core sediments from the Brahmaputra River, India were analysed (15 elements) by the energy-dispersive X-ray fluorescence technique. The Cauvery River load indicates a relative predominance of solute vs. suspended transport. Cauvery River suspended matter is depleted in Al and Si, and enriched in Ca, Mn, Cr, Ni, Cu, Zn and Sr relative to the world's average river suspended matter. As the sampling web covered mainly the Cauvery Delta, the enhanced heavy metal concentrations in the suspended matter are explainable in terms of chemical–physical processes in the zone of mixing. Flocculation of the dissolved metal species causes their transformation in suspended state. Consequently, deltaic suspended matter is one–two orders of magnitude richer in heavy metals than the main river course background. Cauvery surface sediments reflect the average Indian river sediment composition. They have a homogenous composition along the river course and a heavy metal content lower than that of the Cauvery suspended matter. Sedimentation rates in the Cauvery and Brahmaputra are comparable with those published for other Indian rivers. Sediment flux to the Brahmaputra bed is higher than for the Cauvery. Mass accumulation rates for heavy metals in the sediments were determined. It is supposed that the large and synchronous fluctuations in the temporal distribution of the heavy metal mass accumulation rates have been caused by cyclic climatic changes over the Indian sub-continent. An additional supply of transition elements, due to urbanisation and industrial activities, could be assumed to cause the enrichment in the uppermost core layers.
... Trace metal concentrations of YRS sediments show very weak correlation with Fe, Mn and P (except Zn which correlates positively with Fe, r = 0.52; and Co which shows a weak positive correlation with P, r = 0.36,Table 4). Phosphorous is known to be associated with ferric oxides/hydroxides and organic matter in river sediments (Berner and Rao, 1994). Jha et al. (1990) observed a significant co-variation between organic C and P in the Yamuna river sediments. In the present study, covariation of heavy metals with Al and absence of the same with P, Fe and Mn suggest that these metals are mainly associated with clay fractions and that their abundances are not significantly influenced by the presence of o ...
... The role of particle transport and sorting is also evident from comparison of chemical composition of surface sediments with those of suspended particulates of the Yamuna river. The heavy metal (Cr, Cu, Ni, Zn and Pb) concentrations of the Yamuna river sediments (Table 2 ) are lower than those reported for total suspended matter of the river at Baghapat (the most upstream point of sampling in Jha et al., 1990). Suspended particles are finer in size and have higher abundances of Al and clay minerals . ...
Bed sediments of the Yamuna River and its tributaries in the Himalaya (Yamuna River System, YRS) have been analyzed for major elements and trace metals (Sr, Ba, Ni, Cu, Co, Zn, Pb and Cr). These results have been used to charac-terize chemical weathering and transport in the Himalaya, to assess relative mobility of elements during weathering and to understand heavy metal association. Concentrations of major and trace elements of YRS sediments vary between 20 and 50%. In general, elemental variability reduces when data are analyzed individually for the major rivers, suggesting that tributaries draining diverse lithology contribute significant variations. Comparison of sediment chemistry with composi-tion of source rocks and average Upper Continental Crust (UCC) suggests significant loss of Na, K, Ca and Mg from source rocks during weathering, the degree of loss being more for Ca and Na. Chemical index of alteration (CIA) for YRS sediments averages at 59, indicating that weathering in the basin is of moderate intensity. This inference is also supported by major ion chemistry of YRS waters and is attributed to steep gradient and enhanced physical erosion in the basin. Available results seem to indicate that Na and Sr are effectively more mobile than Ba, which is thought to be a combined effect of higher solubility of Na and Sr, and the affinity of Ba to be adsorbed onto solid phase. Heavy metals show significant positive correlation with Al and weak correlation with Fe, Mn and P. These observations suggest that metal concentrations are controlled mainly by clay mineral abundances, and that Fe-Mn oxides and organic matter may be playing less significant role. Heavy metal concentrations of YRS sediments are lower than those of suspended particulates of the Yamuna river, presumably due to higher clay mineral abundances in the latter. Strong association of metals with Al, and lower metal concentrations in bed sediments compared to suspended matter underscores the importance of sediment transport and mineral sorting in influencing the YRS sediment chemistry. Enrichment factor and geo-accumulation index calculated for heavy metals in YRS sediments suggest that they are mainly of natural origin and that anthropogenic activi-ties exert little influence on their abundances. ing the Himalaya (Krishnaswami et al., 1992; Sarin et al., 1992; Pande et al., 1994; Galy and France-Lanord, 1999; Dalai et al., 2002a, 2002b, 2002c, 2003). These studies are based mainly on isotopic and major ion com-position of dissolved load of rivers. Available geochemical studies of river sediments in the Indian Himalaya include reconnaissance survey of the Ganga and the Yamuna (Subramanian, 1987; Jha et al., 1990; Chakrapani and Subramanian, 1996; Subramanian and Ramanathan, 1996; Ramesh et al., 2000) and the Indus (Ahmad et al., 1998). Geochemical studies of sediments in the headwaters of rivers in the Himalaya are limited. The river Yamuna, draining the southern slopes of the Himalaya in its upper reaches, is the largest tributary of the Ganga (Negi, 1991). At the confluence, water dis-charge of the Yamuna is one and half times that of the Ganga (Rao, 1975). The Yamuna and its major tributaries in the Himalaya constitute the Yamuna River System
... This is possibly because of its great complexity, particularly in the monsoon period, for organic matter. A significant amount of Cu is also observed to be affiliated with the residual fraction [42,43]. In different seasons, high percentages of Cd are found in exchangeable (F1) and carbonate (F2) fractions. ...
Behaviour of heavy metals in the environment is widely acknowledged to be assessed by different physicochemical forms of presence rather than their overall concentration. In this study, Tessier 5-step sequential extraction technique was used to measure the trace metal (Mn, Cu, Zn, Fe, Pb, Co, Cd) fractions in surficial sediments in different seasons, in turn, analyse the risk posed by different fractions to the aquatic ecosystem. The findings reveal that residual fraction (F5) is in highest proportion (~44%) among the trace metals analysed. However, the proportion of carbonate and exchangeable fractions was comparatively higher (~24%), posing amajor risk to the aquatic ecosystem. Particle size v/s metal fraction scatter-plots showed that in the case of Cu, Fe and Mn, there is some form of both anthropogenic and natural pollution during the studied period, whereas, in rest of the metals, pollution is due to natural sources. Principal component analysis (PCA) led to the generation of 2 principal components (PCs), which accounted for approximately 80% of the total variance. PC1 and PC2 accounted for 45% and 35% of the total variance, respectively, which helped identify the pollution source as anthropogenic. Then, risk assessment code (RAC) revealed, Zn (41%), Mn (35%), Cu (35%), and Pb (27%) posed ahigher threat in drier months. In contrast, Co (40%) and Cd (48%) pose a higher threat with monsoon onset, showing variation of mobility of different metals in different seasons. Fe is the least mobile among the metals analysed, posing very little to the aquatic environment. Then, comparison with sediment quality guidelines (SQGs) reveals, although their potential hazard is high, they never surpass the SQGs. Thus, trace metal sediment contamination does not pose any risk to the river’s aquatic environment in the present study but calls for stringent measures employment in river pollution abatement.
... Sediments are ecologically important components of the aquatic habitat which play a significant role in maintaining the trophic status of any water body [5] Thus, study of sediment helps in the understanding of pollution effect as the residence time of pollutants in sediment of impacted area is long. Distribution of heavy metals in sediments of the river Ganga and its tributaries have been carried out by several workers [6][7][8]. ...
... Further, the urban discharge also leads to an accumulation of antibiotics in the receiving drains that merges into the Yamuna River [11][12][13][14][15]. Antibiotics such as Ampicillin, Ciprofloxacin, Gatifloxacin, Sparfloxacin, and Cepuroxime have been detected in the Yamuna river at different sites in the New Delhi region [15]. The detection of antibiotics and discharge of a large number of sewage drains into the river hints towards the presence of a pool of resistome residing in the Yamuna [16]. However, only a little is known about the prevalence of ARGs in the river, which is a major source of water for a large population in India. ...
Background
Yamuna, a major tributary of Ganga, which flows through the national capital region of Delhi, is among the major polluted rivers in India. The accumulation of various effluents, toxic chemicals, heavy metals, and increased organic load in the Yamuna directly affects the organisms that thrive inside or around this river. It also makes it an ideal site for studying the impact of pollution on the river microflora, which are sentinels of the water quality.
Results
In this study, the microbial community structure and functional diversity of the Yamuna river water was assessed from the New Delhi region. The community structure of Yamuna during pre-monsoon (June) was found to be significantly different from the post-monsoon (November) time, with Acinetobacter being the most abundant genus during June, and Aeromonas during November. The functional characterization revealed the higher abundance of Methyl-accepting chemotaxis protein in the river water, which could be important for the microbial chemosensory adaptation in the environment. A higher abundance of genes related to nitrogen and sulfur metabolism, metal tolerance, and xenobiotic degradation, and complete degradation pathways of aromatic compounds such as toluene, xylene, benzene and phenol were identified. Further, the results showed the presence of a pool of antibiotic resistance genes in the bacterial microbiome in the Yamuna alongside a large number of broad-spectrum antibiotics, such as carbapenemases and metallo-β-lactamases. Efflux mechanism of resistance was found to dominate among these microbes conferring multi-drug resistance. The Principal Coordinate Analysis of the taxonomic composition of the Yamuna River water with publicly available freshwater and sewage datasets revealed significant differences in the two Yamuna samples and a greater resemblance of pre-monsoon Yamuna sample to sewage sample owing to the higher pollution levels in Yamuna in the pre-monsoon time.
Conclusion
The metagenomic study of the Yamuna river provides the first insights on the bacterial microbiome composition of this large polluted river, and also helps to understand the dynamics in the community structure and functions due to seasonal variations. The presence of antibiotic resistance genes and functional insights on the metabolic potential of a polluted river microbiome are likely to have several applications in health, biotechnology and bioremediation.
... The mobility of metal ions is dependent upon their sorption by sediments and their redistribution with deposition at the sediment-water interface. Further, both mobility and persistence are controlled by the nature of the metal bonding, sediment type and water chemistry (Jha et al. 1990). The mobility of metals is also regulated by the chemically mobile fraction of the sediments. ...
Rivers are the mostly vulnerable water bodies due to carrying off and assimilating pollutants from both point sources and non-point sources. This study deals with the metal pollution in sediments of the Cooum River, Chennai, India. Eleven sampling stations were selected along the 18 km stretch of the Cooum River, which lies in the urban part of the Chennai City and the concentration of metals such as As, Zn, Mn, Ni, Co, Cr, Cu, Pb, Cd, and Hg in the sediments were determined. The study reveals a progressive increase in the concentration of metals in the downstream due to increase in domestic and industrial drainage (out falls) into the river. Spatial distribution of sediment particle size indicated the dominance of smaller particles ranging from 425 to 75 µm. The concentration of metals in the Cooum River sediments was in the following order: As > Zn > Cr > Cu > Pb > Cd > Hg. Significant positive correlations exist between Cd and Zn, Cu and Pb, Cd and Hg, and Cr and Hg. Ecological risk indices denote predominant levels (> 70%) of cadmium throughout the sampling points as indicated from contamination factor. Potential ecological risk assessment specified the alarming levels of cadmium and mercury above the standard limits in the sediments assessed. Based on the observations, it is evident that the Cooum River is highly polluted and it becomes essential that the urban effluents should not be overlooked before their discharge into the river.
... This grouping informs about a potential urban and hydrocarbon spillage process. In this sense, metals Cu and Zn are concentrated in the organic fraction of the sediments as supported for previous studies [22]. The vertical distribution of Zn and Pb in the different layers of the profiles from the Hügli Estuary was previously observed [19] and attributed to river input sediment properties and dredging [23]. ...
The Ganges River receives inputs from highly populated cities of India (New Delhi, Calcutta, among others) and a strong influence of anthropogenic activities until reaching the Bay of Bengal. It is a seasonal river with 80% of discharges occurring between July and October during monsoon. The land-based activities next to the shore lead to discharges of untreated domestic and industrial effluents, inputs of agricultural chemicals, discharges of organic matter (cremations), and discharges of chemicals from aquaculture farms. In spite of the UNESCO declaring Human Patrimony the National Park Sundarbans, located in the delta, contamination has increased over time and it dramatically intensifies during the monsoon period due to the flooding of the drainage basin. Vertical element distribution (Cd, Co, Hg, Ni, Pb, and Zn) was studied in sediments collected in different stations towards the Hügli Estuary. Results determined no vertical gradient associated with the analyzed sediment samples, which informs about severe sediment dynamic in the area that probably relates to tidal hydrodynamics and seasonal variation floods. The multivariate analysis results showed different associations among metals and in some cases between some of them (Co, Zn, Pb, and Cu) and the organic carbon. These allow the identification of different geochemical processes in the area and their relationship with the sources of contamination such as discharge of domestic and industrial effluents and diffuse sources enhanced by the monsoons. Also, an environmental risk value was given to the studied area by comparing the analyzed concentrations to quality guidelines adopted in other countries. It showed an estimated risk associated with the concentration of the metal Cu measured in the area of Kadwip.
... The sequential extraction provides information on digenetic transformation, distribution, bioavailability, mobilization, and transport of the metals in an environment (Kabala and Singh 2001). Despite this fact, only a few studies have reported the metal speciation in Indian rivers (Jha et al. 1990;Jain 2004). ...
We investigated the distribution of different fractions of eight heavy metals (Zn, Cr, Cu, Pb, Cd, Ni, Fe, and Mn) in the bed sediment of the Ganga River. The study was conducted during summer low flow (March to June 2017) considering a 285-km middle stretch of the Ganga River between the Allahabad upstream and the Varanasi downstream. To assess the metal levels from a toxicological perspective, we tested the relationships between metals and sediment microbial/extracellular enzyme activities. Most of the metals showed a large fraction in residual form. However, Zn, Pb, and Cd showed about 20–30% share in the exchangeable form. The total metal concentration poorly reflected the toxicity but the exchangeable fractions did show strong negative correlations (r = − 0.83 to − 0.63; p < 0.01) with microbial/enzyme activities. Also, the nutrients and organic carbon showed strong positive correlations (r = 0.62 to 0.89; p < 0.001) with microbial/enzyme activity. The phosphate showed a strong negative correlation (r = −0.82; p < 0.001) with alkaline phosphatase. The principal component analysis (PCA) and the indices such as contamination factor (CF), enrichment factor (EF), pollution load index (PLI), geoaccumulation index (Igeo), and risk assessment code (RAC) revealed moderate to severe contamination with strong anthropogenic influence. As per the United States Environmental Protection Agency, the metal concentrations at many locations were in the highly toxic range. The study has relevance from a toxicological perspective and for the management of the Ganga River.
... Sediments have been widely used as environmental indicators since they can easily be used to trace contamination sources and to monitor pollutants. They play an important role in the assessment of metal contamination in natural waters (Borovec, 1996, Duzzin et al., 1988, Gonçalves and Boaventura, 1991Huang et al., 1994;Jha et al., 1990;Lietz and Galling, 1989;Pardo et al., 1990;Wardas et al., 1996). Indeed, sediments reveal a high propensity to accumulate, register and eventually integrate through time trace element presence in water. ...
... The reducible fraction contained most of the Pb, with mean values of 61.8, 68.6, and 55.2 % of total Pb in the residential, mixed, and agricultural areas, respectively (Fig. 2-Pb), indicating relatively higher mobility and bioavailability under reducing conditions (Passos et al. 2010). These results were in agreement with the Pb concentrations observed in sediment from the Yamuna River by Jha et al. (1990) and Jain (2004). No more than 4 and 9 % of total Pb was found in the acidsoluble and oxidizable fractions, respectively. ...
Concentrations of heavy metals (Cd, Cr, Cu, Ni, Pb, and Zn) were measured in water, sediments, Ceratophyllum (hornwort), and Bellamya sp. (edible snail) from residential, mixed (industrial and commercial), and agricultural areas with rural rivers in the Taihu Lake region, China. Zn concentrations were the highest, whereas Cd concentrations were the lowest among the six metals in water, sediments, and aquatic organisms. Cd was mainly present in the acid-soluble fraction, Cr in the residual fraction, and Pb in the reducible fraction of sediments. Heavy metal concentrations in water, sediments, and aquatic organisms in the three areas followed the order of the mixed area > residential area > agricultural area. Heavy metal concentrations in aquatic organisms were not only related to total metal concentrations in water and sediments but also to metal speciation concentrations in sediments. In addition, the bio-concentration factor (BCF) values of Cr, Cu, Pb, and Zn for Bellamya sp. were higher than those for Ceratophyllum, whereas the BCF values of Cd and Ni for Bellamya sp. were lower than those for Ceratophyllum. An ecological risk assessment of heavy metals in sediments showed that Cd posed the highest ecological risk to the environment. A health risk assessment showed that consuming Bellamya sp. from the mixed area could cause a potential health risk.
... The patterns of metal speciation are different from each other in sediments of the three areas. There are higher proportions of Cd in the acid-soluble fraction, Cr in the residual fraction, Pb in the reducible fraction in the three areas, which were similar to Cd described by Yang et al. (2009) in sediments from the Yangtze River catchment, Cr found by Nemati et al. (2011) in sediments from Sungai Buloh, and Pb in sediment from River Yamuna by Jha et al. (1990) and Jain (2004). Less of the oxidizable fraction was found in the sediment samples than in the rest of fractions, which was opposite to the studies, the highest contents (greater than 30%) of Cd, Cu, Ni, and Pb in the oxidizable fraction, conducted by Passos Downloaded by [Nanjing Institute of Soil Science] at 21:31 23 October 2014 et al. (2010) in sediments from the Poxim River (Brazil). ...
... The patterns of metal speciation are different from each other in sediments of the three areas. There are higher proportions of Cd in the acid-soluble fraction, Cr in the residual fraction, Pb in the reducible fraction in the three areas, which were similar to Cd described by Yang et al. (2009) in sediments from the Yangtze River catchment, Cr found by Nemati et al. (2011) in sediments from Sungai Buloh, and Pb in sediment from River Yamuna by Jha et al. (1990) and Jain (2004). Less of the oxidizable fraction was found in the sediment samples than in the rest of fractions, which was opposite to the studies, the highest contents (greater than 30%) of Cd, Cu, Ni, and Pb in the oxidizable fraction, conducted by Passos Downloaded by [Nanjing Institute of Soil Science] at 21:31 23 October 2014 et al. (2010) in sediments from the Poxim River (Brazil). ...
Heavy metal speciation and the associated ecological risks were investigated, using a European Community Bureau of Reference sequential extraction procedure, in sediments from the residential, mixed (residential and industrial), and agricultural areas of rural rivers in southern Jiangsu Province, China. Compared with the background values in Jiangsu Province soils, Cd was the metal with the highest contamination level, especially in the mixed area, followed by Cu and Zn. In the sediment samples from the agricultural area, the heavy metal concentrations were no more than two times greater than the background values. There were higher proportions of Cd in the acid-soluble fraction, Cr in the residual fraction, and Pb in the reducible fraction in the three areas. The heavy metal mobility was mainly controlled by the acid-soluble and reducible fractions. Cd could pose extremely high risks to the environment. In addition, the risks of heavy metal to the environment in the three areas followed the order: mixed area > residential area > agricultural area. Furthermore, a risk assessment code analysis showed that most of the sediment samples were classified as being of high to very high risk in the residential and mixed areas because of their Cd, Ni, and Zn concentrations. Heavy metal pollution in the residential and mixed areas is generally serious, and immediate remediation measures need to be taken.
... It consists mainly of grey-coloured fluviatile medium sand deposits interbedded with calciferous gravel-sized concretions, locally known as kankar. The mineral assemblage consists in order of decreasing proportion of quartz, mica (illit) and chlorite, accessory kaolinite, montmorillonite, feldspar and calcite (Jha et al. 1989). The upper aquifer extends down to 12 m below ground level (bgl) at the river and increasing thickness to the east (up to 30-40 mbgl). ...
Hydrogeochemical and hydrodynamic surface/groundwater interactions were investigated at the urban floodplain aquifer in Delhi, India. The heavily polluted Yamuna River is in hydraulic contact to the groundwater and river seepage results in a contamination plume. A conceptual redox zonation was developed based on the occurrence or absence of terminal electron acceptors. The redox zonation shows an inverted zonation from sulphate-reducing conditions close to the river over manganese- and iron-reducing conditions to a mixed oxic/suboxic zone. This study shows that the occurrence of problematic substances such as ammonium and arsenic in the groundwater is a consequence of the high load of untreated sewage in the river in combination with losing river conditions. Sequential extraction of aquifer material was performed to obtain information on geochemical availability of arsenic associated with different mineral phases and binding forms. Geogenic and anthropogenic arsenic sources contribute to overall arsenic concentration, and arsenic is found to be attributed mainly to amorphous iron oxide and sulphidic phases in the sediment. The contamination plume at the urban floodplain aquifer makes the groundwater unfit for drinking water purposes.
... River sediments, therefore, are important sources for the assessment of man-made contamination in rivers. Several studies on the distribution of heavy metals in sediments of the river Ganges and its tributaries have been carried out (Ajmal et al., 1983;Subramanian et al., 1987;Saikia et al., 1988;Jha et al., 1990;Ansari et al., 2000;Dutta and Subramanian, 1998;Ramesh et al., 2000;Singh, 2001). Singh et al. (2002) also reported that highly polluted sediments are adversely affecting the ecological functioning of rivers due to heavy metal mobilization from urban areas into biosphere. ...
Gomti river receives industrial as well as domestic wastes from various drains of Lucknow city. In the process the water and sediment of the river Gomti get contaminated with heavy metals and other pollutants. In the present study, impacts of domestic/industrial wastes on the water and sediment chemistry of river Gomti with special reference to heavy metals have been investigated in different seasons (summer, winter and rainy). For this, seven sampling sites: Gaughat, Mohan Meakin, Martyr's Memorial, Hanuman Setu, Nishatganj bridge, Pipraghat and Malhaur, in the river Gomti in Lucknow region were identified and samples of water and sediments were collected in all the three seasons. In the collected water and sediment samples, six metals (Cd, Cr, Cu, Ni, Pb, and Zn) were analyzed on ICP-AES (Inductively coupled plasma emission spectroscopy) Labtam Plasmalab 8440. High concentrations of all the metals were noticed in water and sediment in rainy season compared to summer and winter. Because in rainy season runoff from open contaminated sites, agricultural field and industries, directly comes into the river without any treatment. In both the cases, the concentration of zinc was maximum (0.091 µg/ml in water and 182.13 µg/g in sediment) and the concentration of cadmium (0.001 µg/ml in water and 17.26 µg/g in sediment) was minimum. Higher concentration of metal in water and sediment during rainy season could be due to the industrial/agricultural/domestic runoff coming into the river.
... This indicates that changes in Eh and pH could lead to some mobilization of Cu. Large proportions of Cu in residual and OM-bound forms have also been observed in aquatic sediments (Singh et al., 1999;Jha et al., 1990;Pardo et al., 1990;Huang et al., 2007). Lead and Zn, which were present at relatively high concentrations but without exceeding the RSCTL in the original dataset, are present in significant amounts in all but the water extractable forms (Figure 39, Figure 40, Table 12). ...
... suggests that a major portion of lead is bound to the Fe – Mn oxide fraction with a moderate amount associated with organic and residual fractions. Our findings are in agreement with earlier studies (Salomons and Forstner, 1980; Tessier et al., 1980; Rauret et al., 1988; Pardo, 1989; Jardo and Hickless, 1989; Gadh et al., 1993; Ryan et al., 2002). Jha et al. (1990) also reported that lead is mostly present in the Fe – Mn oxide fraction in Yamuna sediments at Delhi. High amounts of Pb released during hydroxylamine hydrochloride (HA – HCl) extraction imply that Pb is contained in easily-to-moderately reducible oxide or hydroxide phases (Ryan et al., 2002). However, we cannot rule out the possibility ...
The speciation patterns of heavy metals were assessed with a view to providing information on the bioavailability of metals in the sediment matrix. The results indicate that cadmium is speciated into residual and readily exchangeable forms, while copper speciated into organic bound, residual and Fe-Mn oxide fractions: lead into Fe-Mn oxide, organic and residual fractions; chromium into Fe-Mn oxide, organic and residual fractions; nickel into residual and organic bound fraction; zinc into residual Fe-Mn oxide and carbonate fractions; iron and manganese into Fe-Mn oxide, residual and easily exchangeable fractions. The speciation pattern gave a general picture that the majority of the metals exist either in the organic, or Fe-Mn oxide and residual fractions except for cadmium. It implies that metals that are predominantly in the Fe-Mn oxide and organic fractions can only be remobilised under conditions that change the redox potential of the sediment. There are significant spatial and temporal variations in the speciation patterns of heavy metals in river sediment.
... Sediments have been widely used as environmental indicators and their ability to trace contamination sources is well documented (Bermejo et al. 2003; Camusso et al. 2002; Soares et al. 1999; Ramses et al. 1999; Forstner and Muller 1973). The sediment at the bottom of the water column plays a major role in identifying the pollution scheme of the river systems by heavy metals (Duzzin et al. 1988; Lietz and Galling 1989; Jha et al. 1990; Pardo et al. 1989; Huang et al. 1994; Lapaquellerie et al. 1995; Borovec 1996; Wardas et al. 1996). They may reflect both the current and the past discharges to the water system and can be used to detect the presence of contamination. ...
Heavy metal distribution patterns in river sediments aid in understanding the exogenic cycling of elements as well as in assessing the effect of anthropogenic influences. In India, the Subernarekha river flows over the Precambrian terrain of the Singhbhum craton in eastern India. The rocks are of an iron ore series and the primary rock types are schist and quartzite. One main tributary, the Kharkhai, flows through granite rocks and subsequently flows through the schist and quartzite layers. The Subernarekha flows through the East Singhbhum district, which is one of India’s industrialised areas known for ore mining, steel production, power generation, cement production and other related activities. Freshly deposited river sediments were collected upstream and downstream the industrial zone. Samples were collected from four locations and analysed in <63-μm sediment fraction for heavy metals including Zn, Pb, Cd and Cu by anodic stripping voltammetry. Enrichment of these elements over and above the local natural concentration level has been calculated and reported. Sediments of the present study are classified by Muller’s geo-accumulation index (I
geo) and vary from element to element and with climatic seasons. During pre-monsoon period the maximum I
geo value for Zn is moderately to highly polluted and for Cu and Pb is moderately polluted, respectively, based on the Muller’s standard. Anthropogenic, lithogenic or cumulative effects of both components are the main reasons for such variations in I
geo values. The basic igneous rock layer through which the river flows or a seasonal rivulet that joins with the main river may be the primary source for lithogenic components.
... Akcay et al. (2003) studied heavy metal pollution and speciation in Buyak Menderes and Gediz river sediments. Only a few studies have been reported on the speciation of metals in Indian rivers (Jha et al., 1990;Singh et al., 2000;Jain, 2004). Recently, Jain (2004) in a metal fractionation study of bed sediments of the river Yamuna, India, discussed the Risk Assessment Code (RAC), and found that 30-50% of lead at most of the sites existed in the exchangeable fraction while 30-50% of cadmium at almost all the sites was either exchangeable or carbonate bound and therefore a high risk. ...
A hydrochemical study on a 630 km stretch of river Gomti, a tributary of the river Ganges examined the distribution of heavy metals in sediments and the partitioning of their chemical species between five geochemical phases (exchangeable fraction, carbonate fraction, Fe/Mn oxide fraction, and organic fraction) using Tessier's analytical sequential extraction technique. Most fractions in the sediments associated with the carbonate and the exchangeable fractions were between 11 and 30% except in a few cases where it was more than 50%. According to the Risk Assessment Code (RAC), the sediments having 11–30% carbonate and exchangeable fractions are at medium risk. The concentrations of cadmium and lead at mid Lucknow, Pipraghat, Sultanpur U/S and Sulthanpur D/S are between 31 and 50%. They thus pose a high risk to the environment. Since the concentrations of cadmium and lead at Neemsar (Cd 56.79%; Pb 51%) are higher than 50%, the RAC as very high. In most cases, the average metal concentrations were lower than the standard shale values. Various physicochemical parameters such as pH, total solids, total dissolved solids, total suspended solids, COD, BOD, DO, conductivity, chloride, sulphate, phosphate, fluoride, total alkalinity, total hardness, etc. were also reported.
... The organic matter content detected in station 10 was very high. The partition profiles were very similar to the profile found in the Yamuna River in New Delhi by Jha et al. (1990), where this author observed that copper was mainly associated with the Fe/Mn oxyhydroxides phases, differently from some works that reported the intense association of copper with the organic matter in fluvial sediments (Kuang-Chung et al. 2001, ATSDR 1994. However, a previous work carried out in the surface sediments of the Estrela River by Souza (1986) also observed that copper was mainly associated with the organic phase, different from the present work. ...
In this study, the geochemical analysis of ten sediment samples collected along the fluvial system of the Estrela River, which flows into the northern portion of Guanabara Bay, shows the presence of anthropogenic impacts in this area. Concentrations of Fe, Mn, Zn, Cu, Pb, Cr and Ni obtained were slightly higher, when compared with values found in natural environments. The particle size and organic matter content in most of the analyzed stations showed features not conducive to the accumulation of pollutants due to the low organic matter content and the strong presence of sand fraction. There was also the fractionation of heavy metals in sediments and it was found the prominence of residual and reducible phase, besides the significant occurrence of organic fractions in some analyzed stations. These factors, thus, highlight the potential risks of contamination, where the metals associated with the organic phase can become bioavailable in processes of dissolution, provided by physico-chemical changes that can occur in this aquatic environment.
... As reported earlier [3] , that highly polluted sediments are adversely affecting the ecological functioning of rivers due to heavy metal mobilization from urban areas into biosphere. Distribution of heavy metals in sediments of the river Ganga and its tributaries have been carried out by several workers [4][5][6][7][8][9][10][11] . Monitoring of Ganga River from Rishikesh to Varanasi indicated that Kannauj to Kanpur and Varanasi are the most polluted stretches of the river Ganga [12][13] . ...
The objective of this study was the sediment quality assessment of Ganga River at Kanpur city where effluents from tannery industries are discharged. Sediment samples from upstream and downstream area were collected and analyzed for trace metals and toxicity bioassay. Among various trace metals examined Cr in downstream sediment was 30-fold higher than in upstream sediment and its concentration was above the probable effect level. In general trace metals in the downstream sediment were found higher compared to reported earlier. Seed germination bioassay revealed negligible effect on the growth of root but the shoot growth was stunted in seeds exposed to downstream sediments. Trace metals determined in sediment elutriate showed poor elution of metals in aqueous phase but elutriates exerted toxic effects on both root and shoot growth, suggesting presence of other bioavailable toxic factor associated with sediment. The study revealed that seed germination bioassay may be used to differentiate contaminated and uncontaminated sediment.
... & Schn.) collected from two distinct sites of the river Yamuna. A limnological study (Rai, 1974) and some water analysis parameters studies (Jha et al., 1990;Jhingaran and Joshi, 1989) clearly demonstrate the deteriorating condition of water quality of river Yamuna. To assess the pollution load in Yamuna resulting from myriad of anthropogenic activities suitable biomarkers for biomonitoring have therefore been made to develop. ...
Various oxidative stress biomarkers in gill, kidney and liver tissues in the Indian freshwater fish Wallago attu (Bl. & Schn.) were investigated. Fish were collected from two sites along the river Yamuna, which differ in their extent and type of pollution load. A comparison was made between the biomarker responses and general water chemistry at the two sites. The oxidative stress biomarkers that were analyzed included superoxide dismutase (SOD), catalase (CAT), xanthine oxidase (XOD) and glutathione redox cycle enzymes viz., glutathione peroxidase (GPx), glutathione reductase (GR) and glucose 6-phosphate dehydrogenase (G6PD). Levels of reduced glutathione (GSH) and lipid peroxidation (LPO) were also evaluated. All biomarkers; SOD (P<0.001 in liver, kidney and gill), XOD (P<0.01 in kidney and P<0.001 in liver and gill), GR (P<0.01 in liver, P>0.05 in kidney and P<0.001 in gill), G6PD (P<0.001 in liver, P>0.05 in kidney and P<0.01 in gill), GSH (P<0.001 in liver, kidney and gill) and LPO (P>0.05 in liver, kidney and gill) were found to be substantially higher in the fish collected from Panipat when compared with values in tissues of fish collected from Agra site. GPx and CAT showed a varied response. GPx activity was higher (P<0.001) in gills and kidney of the fish collected at Panipat site. However, liver showed significant low values (P<0.01) when compared with Agra site values. CAT activity was found to be significantly low, in both liver (P<0.01) and kidney (P<0.001) whereas in gills non-significant (P>0.05) low values were observed. Water chemistry data at two sites indicated that Panipat site with higher biochemical oxygen demand, chemical oxygen demand, pH and low dissolved oxygen was comparatively more polluted than Agra site. Industrial activity profile of both the sites also indicates that Panipat has vigorous industrial activity coupled with intensive use of chemicals in agricultural practices in Haryana state. The findings of the present investigation provide a rational use of oxidative stress biomarkers in aquatic ecosystem pollution biomonitoring. This is also the first such attempt reported from India.
... Owing to the need for validation of extraction schemes, the EC Measurement and Testing Programme (formerly BCR) has organized a project for improving the quality of determinations of extractable trace metals, where development and validation of extraction procedures has been discussed [11] [12]. Although the importance of metal speciation and fractionation has been realized in developed countries, the subject has not really taken off in our country and only few references are available on the speciation of metals in Indian rivers [13] [14] [15] [16]. The River Yamuna is one of the major rivers of the country and traverses a distance of 1376 km from its source in the Himalayas to its confluence with River Ganga at Allahabad. ...
The pollution of aquatic ecosystem by heavy metals has assumed serious proportions due to their toxicity and accumulative behavior. The toxicity and fate of the water borne metal is dependent on its chemical form and therefore quantification of the different forms of metal is more meaningful than the estimation of its total metal concentrations. In this study fractionation of metal ions on bed sediments of River Yamuna has been studied to determine the eco-toxic potential of metal ions. The investigations suggest that copper have a tendency to remain associated with residual, reducible and carbonate fractions. The Risk Assessment Code reveal that about 30-50% of lead at most of the sites exist in exchangeable fraction while 30-50% of cadmium at almost all the sites is either exchangeable or carbonate bound and therefore comes under the high risk category and can easily enter the food chain. Most of the copper is in immobile fraction at Delhi while at other sites, a sizable portion (10-30%) is found in carbonate fraction thus posing medium risk for the aquatic environment. Fractionation pattern of zinc shows low to medium risk to aquatic environment.
Quantitative indices are classically employed to evaluate the contamination status of metals with reference to the baseline concentrations. The baselines vary considerably across different geographical zones. It is imperative to determine the local geochemical baseline to evaluate the contamination status. No study has been done to establish the background concentrations in tropical rivers of this region. This paper reports the background concentrations of metals in water and sediment of the Baleh River, Sarawak, derived based on the statistical methods where the areas possibly disturbed are distinguished from the undisturbed area. The baseline levels of six elements in water determined were Al (0.34 mg/L), Fe (0.51 mg/L), Mn (0.12 mg/L), Cu (0.01 mg/L), Pb (0.03 mg/L), and Zn (0.05 mg/L). Arsenic and selenium were below the detection limit. For sediment, the background values were established according to statistical methods including (mean + 2σ), iterative 2σ, cumulative distribution frequency, interquartile, and calculation distribution function. The background values derived using the iterative 2σ algorithm and calculated distribution function were relatively lower. The baseline levels calculated were within the range reported in the literatures mainly from tropical and sub-tropical regions. The upper limits proposed for nine elements in sediment were Al (100,879 mg/kg), Cr (75.45 mg/kg), Cu (34.59 mg/kg), Fe (37,823 mg/kg), Mn (793 mg/kg), Ni (22.88 mg/kg), Pb (27.26 mg/kg), Zn (70.64 mg/kg), and Hg (0.33 mg/kg). Quantitative indices calculated suggest low risk of contamination at the Baleh River.
p class="Default">The aim of this work was speciation of heavy metals on the level of the geochemical background; in bottom sediments of the Bagmati River in Kathmandu valley. The distribution and accumulation of heavy metals in the sediments of the Bagmati River were investigated. Sediment samples from six locations were collected and characterized for metals content (cadmium, lead, copper and zinc). The determination of extractable heavy metals such as, Cd, Pb, Cu and Zn, in the sediment samples was carried out by atomic absorption spectrometry. The study has been conducted using five steps sequential extraction procedure described by tessier. Apart from total concentration, the distribution of the above metals into five fractions: exchangeable, bound to carbonates, bound to Fe-Mn oxides, bound to organic matter, and residual, was studied by means of an analytical procedure involving sequential chemical extraction. The result obtained showed total metal concentration to be in the range of Cd 0.89-2.29 mg/kg; Pb 57.58-221mg/kg; Cu 52.2 -198.17 mg/kg and 78.23-362.90 mg/kg in all the areas studied. The fractionated toxic metals like Cd, and Pb were observed to be in the range of 15-36%, and 11- 29%, respectively, in mobile or bio-available fractions of sediments. This potentially mobile fraction could pose a serious threat, with respect to contamination of waterways and aquatic environment.
Journal of Hydrology and Meteorology, Vol. 9(1) 2015, p.119-128</p
The toxicity and availability of heavy metals in soil are determined by modes of occurrence of metals. Therefore, the quantification of associations of heavy metals is more significant than the assessment of their total concentrations. Thirty soil samples that were collected from coal mining areas with different mining durations in Huainan Coalfield were employed to determine the modes of occurrence and potential environmental implications of heavy metals. Sequential chemical extraction procedure was carried out to determine the fractionation profiles of heavy metals. The elevated concentrations of heavy metals in the mining activities areas indicated that the mining activities (mining, transportation, utilization and waste disposal) might be one of the sources for the heavy metal pollution in soil. The fractionation characterizations are various among different heavy metals. According to the international sediment quality guidelines (SQGs) calculations, the adverse biological effects caused by Cd, Cr, Pb and Zn are expected to be negligible. For As and Cu, the occasional adverse biological effects are predicted. The risk assessment code reveals that these heavy metals could pose a medium risk to the ecosystem. Consequently, environmental issues involved in heavy metals in the studied coal mining area soil deserve urgent concern.
The present study endeavors to identify the groundwater contamination problems in Baddi-Barotiwala Industrial belt of District Solan, Himachal Pradesh, India. The dense unplanned industrial establishments have negatively affected the groundwater quality in the study area. Groundwater samples from 44 different locations and sources were collected and subjected to standard analytical techniques for physico-chemical analysis. The results obtained were compared with the Bureau of Indian Standards (BIS: IS: 10500, 2003) guidelines for drinking water suitability in relation to possible health hazards. From the heavy metal analysis it can be inferred that high concentrations of Fe, Cu, Pb and Mn has rendered the groundwater unsuitable for drinking purposes. The disposal of untreated effluents from various industrial units may be the source of groundwater contamination in the area of concern. It is indicative that the quality of groundwater is deteriorating with the ever increasing menace of industrialization in this solace of heavenly abode.
The concentrations of Cr and Ni and other heavy metals (Cd, Cu, Pb, Zn) have been determined in stream sediments collected into the Cecina River basin (Tuscany, Italy) in order to evaluate Cr and Ni levels and their spatial distribution and origin. An aqua regia digestion coupled to ICP-MS analysis has been performed on the samples. The distribution of Cr and Ni concentration as a function of grain size was also investigated, comparing finer samples (< 63 μm) and coarse samples (< 2000 μm). In Possera Creek samples, a left tributary of the Cecina River, another sieve fraction (< 125 μm) was sampled. The high lev- els of Cr and Ni in the stream sediments often exceed the thresholds of the Italian law currently in force (Legislative Decree No. 152/2006). Multivariate data analysis techniques (Hierarchical Clustering Analysis, HCA) were used to obtain information about the potential sources of heavy metals. The results indicate an Cr and Ni enrichment in stream sediments due to the presence of some extensive outcrops of serpentinized ultramafic rocks (ophiolites). The enrichment is major in the < 2000 μm fraction compared to the < 63 μm fraction.
Bed, suspended and core sediments collected from the entire region of the basin were analysed to determine the elemental chemistry of the sediments of the Damodar river basin. The analytical results show that bulk sediment chemistry consists mostly (>75%) of five elements. Si, Al, K, Fe and Na. Mean composition has indicated that the Damodar sediments are depleted in Ca, Mg and heavy metals and enriched in Si and K as compared to the other Indian river basins. The concentrations of heavy metals in the suspended sediments are significantly higher than the bed sediments. In general, heavy metal concentration increases towards the finer size fractions. The depth variation of heavy metals in the core sediments shows no specific trend. Speciation studies show that the lithogcnic phase is the major sink for heavy metals. Fc-Mn oxide and organic fractions are the major nonlithogenic phases and Zn is the major constituent of the nonlithogenic phase. Gcoaccumulation indices calculated for Fe, Mn, Cu and Zn indicate that Damodar sediments are not polluted with respect to these metals.
The Yamuna river is the largest tributary of the Ganges river system. It originates in the Himalayas and flows through a varied geological terrain encompassing a large basin area. Metals Fe, Mn, Pb, Zn, Cu in different chemical fractions of suspended sediments such as exchangeable, carbonates, Fe-Mn oxides, organics and residual fractions were studied. Phosphorus associated with different chemical forms are discussed. The metals are mostly associated with residual fractions in the sediments followed by organics, Fe-Mn oxides, exhangeable and carbonates. Intensive use of chemical fertilizers and pesticides in agriculture in the basin affects the high inorganic phosphorus content in sediments.
A sequential technique for extraction of metals from sediments (modified Tessier method) – was used to determine the distribution of the metals Fe, Mn, Pb, Cd, Cu, and Zn in the major sedimentary phases (available, reducible, oxidisable, and residual) in marine sediment samples from six Red Sea Islands. The total metal content was also determined. The oxidizable fraction showed strong association of the metals with organic matter and sulfides. Overall, the total trace metal concentrations in the sediment samples were lower than in previous studies, except for Cd, Pb, and Zn, caused by increasing human activities and landfilling operations on the Red Sea coast. Descriptive data analysis was performed by using statistical method.
The ability of aquatic plants to absorb, translocate and concentrate metal has led to the development of various plant based treatment system. Eichornea crassipes is employed for the removal of toxic metals from waste water. The metal bioaccumulation capacity of a common anchored hydrophyte, Eichornea crassipes was reported that the plant could absorb significant amount of heavy metals like chromium, cadmium, zinc, lead. The experimental results are concluded by taking results from the water sample of metals can also be enhanced by chemical treatment. Indian water hyacinth used for phytoextraction of heavy metals in combination with EDTA. This paper presents the results of phytoextraction of heavy metals from the waste water using chelating agents EDTA.
Sequential chemical extraction was used to assess trace metal speciation and availability in sediments from Abalagada-Aboh catchments in the Niger Delta that have received significant impact of crude oil spillage. The proportions of trace metals in the various geochemical fractions were variable. The result of speciation among the five geochemical fractions indicates that Cd was associated with easily exchangeable/adsorbed and carbonate fractions, Cu and Cr predominantly to organic and residual fraction, Pb was associated with Fe-Mn oxides and carbonate fractions, Ni to residual and Fe-Mn oxides, Mn was associated with Fe-Mn oxides and residual and Zn was associated with carbonate and Fe-Mn oxide fractions. The data revealed that Cd, Pb, Zn and Ni have high mobility indices and are thus relatively labile and bioavailable to aquatic flora and fauna.
Fractionation of the metals Cd, Cr, Cu, Ni, Pb and Zn in sediments was performed for samples collected from eight locations in the Poxim river estuary of Sergipe State, northeast Brazil, using the 3-stage sequential extraction procedure proposed by the European Community Bureau of Reference (BCR). The extraction method was found to be satisfactory for analysis of certified reference material BCR-701, with recovery values ranging from 85% (Cu) to 117% (Cr). The detection limits obtained were 0.001 to 0.305 µg g− 1. Zn exhibited greatest mobility and bioavailability, indicative of anthropogenic sources, while Cr was mainly found in the residual fraction and could be used as an indicator for the contribution from natural sources. Cd, Cu, Ni and Pb were associated with the oxidizable fraction, and Pb, Cr and Ni with the reducible fraction. Principal component analysis (PCA) clearly separated the metals into three groups: I (Zn); II (Pb); III (Cd, Cu, Cr and Ni). These groupings were mainly due to different distributions of the metals in the various fractions, in sediments from the different locations. Risk assessment code (RAC) analysis indicated that although the metals presented a moderate overall risk to the aquatic environment, nickel showed a low risk (RAC < 10%) at three sites, while zinc presented a high risk (RAC > 30%) at four other sites.
Almost the entire suspended load of Yamuna River is transported during the monsoon period; quartz and illite are the dominant minerals of these suspended sediments. Basin lithology, tributary contributions, and sediment grain size seem to control mineral distribution in the sediments. Trace metal concentrations of Yamuna core sediments reflect their mineralogical composition. Illite is the chief clay mineral of the Himalayan river sediments. The mineralogical characteristics of the Himalayan river sediments differ significantly from the Peninsular Indian rivers, which chiefly carry montmorillonite.
Heavy metal transport in Cauvery river chiefly takes place in the particulate form. Tributaries Hemevathi and Kabini draining highly mineralized areas contribute significantly to the heavy metal load of the Cauvery river. Particulate metal transport is influenced by the presence of major dams built across the river. Factor analysis of the elemental data identifies two major group of heavy metals, (a) Fe, Mn, Cr, V and Ti and (b) Cu, Pb and Zn in the suspended sediments of Cauvery river. Heavy metals in surface sediments show wide variations in their concentrations due to the non-uniform grain size distribution of the sediments. The elements Fe, Mn, Pb, Cu, Zn, Ni, Co and As are dominantly present in the m fraction of the river sediments. Speciation studies show that Fe-Mn oxide phase held the largest share of heavy metals in the sediments. The depth variation of heavy metals in the core sediments suggest their similar mobility during diagenesis. Geoaccumulation indices calculated suggest that Cd, Zn, Cr, Pb, Cu and Ni are enriched in sediments several times over background values.
A total of 121 bed sediment samples were collected from a 5.8-km stretch of Manoa Stream, Hawaii. Samples were physically
partitioned into two grain-size fractions, <63 μm and 63–125 μm, acid digested and analyzed by ICP-AES and FAAS. Non-parametric
matched-pair statistical testing and correlation analysis were used to assess differences and strengths of association between
the two fractions for Al, Ba, Cu, Fe, Mn, Ni, Pb, Ti and Zn. Results indicated statistically significant differences between
fractions for all elements except Mn. Concentrations were significantly greater in the <63 μm fraction for Al, Cu, Pb, Ti
and Zn, while Ba, Fe and Ni were higher in the 63–125 μm fraction. Though some elements had statistically significant differences
between fractions (Al, Ba, Fe and Zn) percentage differences were in the range of analytical precision of the instrument and
thus differences were not practically significant. Correlation analysis indicated strong positive associations for all elements
between the two fractions (p<0.0001). Three contamination indices indicated similar degrees of pollution for each size fraction
for four elements having an anthropogenic signal (Ba, Cu, Pb and Zn). The environmental information obtained from the 63–125 μm
fraction was essentially equivalent to that from the <63 μm fraction. In this system it is clear that both bed sediment fractions
indicate anthropogenic enrichment of trace metals, especially Pb, and further supports previous research that has found that
aquatic sediments are critical median for tracing sources of pollution.
Freshly deposited stream sediments from six urban centres of the Ganga Plain were collected and analysed for heavy metals
to obtain a general scenery of sediment quality. The concentrations of heavy metals varied within a wide range for Cr (115–817),
Mn (440–1 750), Fe (28 700–61 100), Co (11.7–29.0), Ni (35–538), Cu (33–1 204), Zn (90–1 974), Pb (14–856) and Cd (0.14–114.8)
in mg kg-1. Metal enrichment factors for the stream sediments were <1.5 for Mn, Fe and Co; 1.5–4.1 for Cr, Ni, Cu, Zn and Pb; and 34
for Cd. The anthropogenic source in metals concentrations contributes to 59% Cr, 49% Cu, 52% Zn, 51% Pb and 77% Cd. High positive
correlation between concentrations of Cr/Ni, Cr/Cu, Cr/Zn, Ni/Zn, Ni/Cu, Cu/Zn, Cu/Cd, Cu/Pb, Fe/Co, Mn/Co, Zn/Cd, Zn/Pb and
Cd/Pb indicate either their common urban origin or their common sink in the stream sediments. The binding capacity of selected
metals to sediment carbon and sulphur decreases in order of Zn > Cu > Cr > Ni and Cu > Zn > Cr > Ni, respectively. Stream
sediments from Lucknow, Kanpur, Delhi and Agra urban centres have been classified by the proposed Sediment Pollution Index
as highly polluted to dangerous sediments. Heavy metal analysis in the <20-μm-fraction of stream sediments appears to be an
adequate method for the environmental assessment of urbanisation activities on alluvial rivers. The present study reveals
that urban centres act as sources of Cr, Ni, Cu, Zn, Pb and Cd and cause metallic sediment pollution in rivers of the Ganga
Plain.
Heavy metals distribution in core sediments, different size fractions of bed sediments (>212 urn, 90-212 jam, 63–90 urn, 53–63 urn, < 53="" urn),="" and="" suspended="" sediments="" (="">30 urn, 20–30 m, 10–20 urn, 2–10 urn, m) have been discussed. Pb, Zn, and Cr have been accumulating in recent years in the sediments. Si, Al, Fe, Ca, and Mg dominate the bed and suspended sediment composition. Metals show increasing concentrations in finer sediments. Applying multivariate analysis to sediment composition, metals have been grouped into different factors depending upon their source of origin. Chemical fractionation studies on suspended and bed sediments show Fe, Zn, Cu, and Pb are associated with the residual fraction and Mn with the exchangeable fraction.
Sediments have been used to detect sources of contamination in a catchment of the Port Jackson (Sydney Harbour) estuary and
to evaluate the effects of different land-use practices on the fluvial environment. Mean enrichment (mean concentrations over
pre-anthropogenic background) of size-normalized (<62.5 μm) aquatic sediment is 10 × for Cu, 20× for Pb and 90× for Zn adjacent
to industrialized areas and 2×, 7× and 7×, respectively for these metals in highly urbanized subcatchments. Diffuse sources
contribute minor metals to fluvial sediment even in the most underdeveloped subcatchment (2×, 3× and 3× for Cu, Pb and Zn
respectively). Organochlorine pesticide residue concentrations parallel heavy-metal trends due to a common mixed industrial
base. Effects-based sediment criteria suggest that some adverse biological impacts are probably occurring in streams flowing
through the industrial areas. This interpretation is supported by sequential extraction data which show that a moderate proportion
of total heavy metals, especially Zn, is associated with the more bioavailable exchangeable/adsorbed phases in these aquatic
sediments. High total suspended solid loads in water downstream of one of the industrial centers, and high particle-bound
Cu and Pb concentrations, suggest that most contaminants exiting the catchment do so in association with the solid phase.
The abundances of several major (Na, Ca, Mg, K, Al, Ti, Fe) and minor elements (Sr, Ba, Mn, P, V, Cr, Ni, Cu and Zn) have been measured in twenty-eight sediment samples from seventeen rivers belonging to the Krishna headwaters and west flowing Western Ghat rivers, all of which drain the Deccan Trap basalts. These results, particularly those of Na, Ca, Mg and Sr coupled with those reported for these elements in the dissolved phase of the same rivers, provide an assessment of their relative mobility and insight into the nature of chemical weathering of Deccan basalts. The sediments are heavily depleted in Na, Ca, Mg and Sr relative to parent basalts (by ∼ 60%). The abundance ratios of these elements in sediments are roughly the same as those in basalts and in dissolved phases of these rivers [Das, A., Krishnaswami S., Sarin M. M., Pande K., 2005a. Chemical weathering in the Krishna basin and the Western Ghats of the Deccan Traps: Rates of basalt weathering and their controls. Geochim. Cosmochim. Acta 69, 2067–2084.], suggesting their near congruent release from basalts to water during chemical weathering, both at present and over the residence time of particles in the basin. K and Ba show limited mobility relative to the above four elements. The abundances of K and Ba are strongly correlated, most likely due to their association in rock forming minerals. Al, Fe and Ti, are generally enriched in the sediments, resulting from the loss of more mobile elements from basalts and their association with secondary minerals formed during weathering. The data also provide evidence for the fractionation of Fe and Al during chemical weathering and erosion. Fe and Ti exhibit significant correlation, attributable either to their co-occurrence in weathering resistant minerals and/or due to scavenging of Ti by Fe oxy-hydroxides formed during weathering of basalts. The abundance of minor elements (Mn, P, V, Cr, Ni, Cu and Zn) and their ratios with Al show significant scatter, by and large bracketing the range reported for Deccan basalts. The wide and overlapping ranges in the concentration of these elements and their ratios relative to Al, between sediments and basalts place severe constraints in assessing their mobility during weathering and erosion, and in judging the role of anthropogenic sources in contributing to their abundances. Among the minor elements, there is a hint that Zn concentration may have been influenced by anthropogenic inputs. Mn, V and Ni, analogous to Ti, show significant correlation with Fe, either due to their association with Fe–Ti minerals or their sequestration by Fe oxy-hydroxides. The mobility of elements during weathering and erosion of Deccan basalts follows the trend (Na ≈ Ca ≥ Mg ≈ Sr) > (K ≥ Ba) > (Al ≥ Fe ≈ Ti).There is considerable spatial variability in the intensity of chemical weathering of Deccan basalts. The CIA (Chemical Index of Alteration) values for the sediment range between 42 and 92, compared to ∼ 37 for the Deccan basalts. The lower CIA values are in sediments richer in CaCO3. This may be a result of semi-arid climate of the region which facilitate CaCO3 precipitation and restrict chemical weathering/erosion. Higher CIA values are generally associated with sediments from basins with higher runoff. Modeling the major element composition of sediment and water yields estimates of particulate abundances in water. These estimates agree with the measured values within a factor of ∼ 2 for some of the rivers whereas in some others they differ by more than a factor of 3–4. The use of sediment composition instead of that of the suspended matter, spatial and temporal variations in sediment flux and non-steady state erosion all can contribute to this discrepancy. These factors also seem to be contributing to difference in CO2 consumption estimated from sediment composition and that reported based on dissolved phase data.
The distribution of trace metals (Cu, Zn, Fe, Mn, Cd, Cr, Pb, and Ni) in water, suspended and bed sediments of the River Hindon, a highly polluted river in western Uttar Pradesh (India) has been studied. The river is polluted by municipal, industrial and agricultural effluents, and flows through the city of Saharanpur, Muzaffarnagar and Ghaziabad districts. The heavy metal concentrations in water were observed to depend largely on the amount of flowing water and are negatively correlated with flow. Sediment analysis indicates that the large amount of heavy metals is associated with organic matter, the fine-grained sediment fraction and Fe/Mn hydrous oxides. A high positive correlation of most of the metal ions in sediments with iron, manganese and organic matter indicate that these constituents play a major role in transport of metal ions. The heavy metal concentrations generally increased with the decreasing particle size of the sediments. Lower metal concentrations in bed sediments during post-monsoon season established that monsoon had a slight effect on status of metals in sediments by causing renewal and mobilization of metals from the sediments.
The search for a better understanding of heavy metal distribution in large river sediments is a major concern in the exogenic cycling of elements through fluvial processes and in assessing the effects of anthropogenic influences. From the Asian continent, the Ganges River contributes a significant amount of sediments to the world's ocean. Freshly deposited sediments of the Ganges River were analyzed from 27 locations along the 1700-km-long channel length by atomic absorption spectrophotometry to determine heavy metal concentration. Total metal concentration in the <20-μm-sediment fraction varies in the range of Cr 121–200 mg/kg, Mn 1150–3070 mg/kg, Fe 34,100–46,200 mg/kg, Co 14.7–25.3 mg/kg, Ni 35–63 mg/kg, Cu 44–69 mg/kg, Zn 87–181 mg/kg, Cd 0.41–1.31 mg/kg and Pb 18–35 mg/kg. Baseline concentration of the river sediments was established for Cr 147 mg/kg, Mn 1764 mg/kg, Fe 40,346 mg/kg, Co 19.2 mg/kg, Ni 47 mg/kg, Cu 55 mg/kg, Zn 105 mg/kg, Cd 0.58 mg/kg and Pb 22 mg/kg. Higher concentration of lithophile elements (Cr and Mn) than the world average indicates that the Ganges River basin receives contribution from basic rocks in crystalline zone of the Himalayan region. In the upper 700-km-long Ganges River segments (UGR), heavy metal profiles (except for Mn) show distinct downstream decreasing trend due to physical sorting of river sediments. River sediments of the northern Indian craton are enriched in Cr, Fe, Co, Ni and Cu. In comparison to high sediment influx by the Himalayan rivers, the northern Indian craton rivers play insignificant role in controlling heavy metal distribution at regional level in 1000-km-long segment of the lower Ganges River (LGR). Metal concentration increased in the clay size fraction by a factor of 1.5–2.5 as compared to the established baseline concentration in the <20-μm-sediment fraction. The Ganges River sediments of the present study can be classified by Müller's geo-accumulation index as basically unpolluted with respect to these heavy metals. The concentration of Cr, Ni and Cu was reported above the lowest effect level (LEL) that may have adverse effect on the biogeochemistry of the river's environment. The Ganges River transports 109×103 tons Cr; 1313×103 tons Mn; 30,020×103 tons Fe; 14×103 tons Co; 35×103 tons Ni; 41×103 tons Cu; 78×103 tons Zn; 0.43×103 tons Cd and 16.4×103 tons Pb annually to the Bay of Bengal. The extensive physical weathering of the Himalayas and monsoon-controlled fluvial process results in the strong homogenization in heavy metal distribution in the river sediments.
The chemical forms of Lead, Zinc, Chromium, Cobalt, Nickel and Copper have been determined using the fractionation scheme of Tessier et al. (1979) and Chao (1972) in the bed sediments of Jhanji River, Assam, India. Almost a similar trend throughout the stretch with no significant spatial variation has been observed in the present study. Significant association with the residual fraction (F5) and a scavenging action by the Fe-Mn oxide fraction (F3b) of the sediments were observed. Except copper, no significant association of other metals with the organic fraction (F4) was observed. Thus, they cannot be easily leached out and may pose less environmental risk. The sediment characteristics played a significant role in defining the chemical forms of the metals present in the sediments.
The chemical forms of cadmium, copper, lead and zinc have been determined using the fractionation scheme of Tessier et al. in the bed sediments of River Yamuna. Sediment characteristics do not show any significant variations except that carbonate content is consistently higher in the post-monsoon season. Silicon and aluminium are the most abundant elements followed by K, Na, Ca, Fe, Mg and Mn in that order, the essential minerals being quartz and biotite. The speciation profiles for a particular metal show a similar trend throughout the stretch with no significant spatial variations. Cadmium is mostly associated with carbonate content and thus has a possibility of becoming readily bioavailable. Major fraction of copper is bound to organic matter while that of zinc to FeMn oxide. Thus they cannot be easily leached out and may pose less environmental risk. Major percentage of lead is found in the FeMn oxide fraction; moderate contributions being made by carbonate and residual fractions. The total lead in the sediments is higher, therefore even a small fraction of lead bound to carbonate content can pose problems to the ecosystem. There are good correlations between the different constituents and the major metal fractions associated with it.
This study aims to investigate the pollution rate of heavy metals on the western seaboard of Bandarabbas in southeast Iran using a new pollution index. The bulk of the analysis was conducted on sediments, followed by selection of a few samples to perform experiments on chemical partitioning studies as well as biological accessibility. On this basis, the proportions of natural and anthropogenic elements were calculated. Finally, with regard to chemical separation results, the pollution rate was calculated based on Muller's geo-chemical index, enrichment factor, pollution index, and a new "Risk" index. Chemical separation showed the anthropogenic origin of elements are as follows: Ni(27.5%) > Zn(6.5%) > Pb(2%) > Al (0.2%). The newly developed pollution index is indicative of "low environmental pollution "for Ni.
The chemical forms of FE, Mn, Zn, Cu, Cr, Pb and Cd in the Yellow River sediment have been studied and the comparison with the Yamaska and Rhine River sediments has been made. The average contents of metals are below their respectdive contents in the average shale. Fe, Cr and Pb show inhomogeneous distribution in the association fractions presenting contrast to Mn distribution. Large percentages of Cu and Zn are found in the organic fraction. The distribution ratios of metals between the easiliy and moderately reducible fractions seem to show a difference of the accumulation tendency of metals in the case of unpolluted and polluted river sediments.
Suspended and bed sediments collected from the entire region of the Krishna River and its major tributaries were analyzed for heavy metals (V, Cr, Mn, Fe, Co, Ni, Cu, Zn, and Pb) by the thin-film energy dispersive x-ray fluorescence technique. There is considerable variation in the concentration of elements towards downstream, which may be due to the variation in the subbasin geology and various degrees of human impact. Suspended particles are enriched in heavy metals throughout the basin relative to bed sediments. The heavy metals are enriched in coarse size fractions (10–90 m) throughout the Krishna River except its tributary Bhima, where finer fractions (2 m) dominate. Transition elements correlate very well with each other. There is a striking similarity between the bed sediments of Krishna River and the Indian average. When the annual heavy metal flux carried by the Krishna River was estimated, and viewed in relation to the other major riverine transport, the Krishna is seen to be a minor contributor of heavy metals to the Bay of Bengal.
The sediment load carried by the Uhlas river comprises lithogenic metals from chemical weathering of basaltic rocks and heavy metals deriving from the industrial effluent along one section of the river. Sewage disposal also contributes to the water pollution. Describes analysis of water and sediment samples (polluted and non-polluted sites), over a period of three years. Water samples were monitored for pH, dissolved/suspended solids, heavy metals, nitrate and phosphate. Sediments were analysed for particle size and heavy metal content. Adjacent soils were analysed and their capacity to contain the heavy metal pollutants estimated by adsorption/desorption/resorption tests. Discusses possible application of the polluted water for land irrigation. (C.J.U.)
Energy-dispersive x-ray fluorescence is advantageous for trace analysis of soils present as thin films. A target thickness of about 2 mg cm-2 provides a compromise between optimal sensitivity and minimal absorption effect or optimal accuracy. Sample preparation involves only suspending the finely ground soil in water and drying this suspension on a thin mylar foil glued on a ring that fits into the x.r.f. spectrometer. The “effective sample weight” present in the exciting beam area is computed from the scatter peaks, a method that cancels out target heterogeneity problems. High accuracy is demonstrated for many elements in reference soil and rock materials; a precision around 5% and a detection limit around 10 ppm can be achieved. As an illustration, results for 16 trace elements and preliminary interpretation are given for a series of pedologically important soil samples from Brasil.
Maximum mass transfer, in the Yamuna River takes place during the monsoon season. The sediment load constitutes 58–86% of the total load carried by the river depending upon the sites. Tributaries are chemically more active than the mainstream. The total load of the river seems to be controlled by lithology. At Allahabad, the Yamuna carries 42 × 106t dissolved chemical load and 64 × 106t sediment load to the Ganges river.The TSM/TDS ratio shows that upstream physical weathering is more dominant than chemical weathering. The negative relation between basin area and total erosion rate and the positive relation between the chemical and sediment erosion in the Yamuna basin is in agreement with the global trend. The average chemical erosion rate (165 t km−2yr−1) of the Yamuna is much higher than that of the Ganges and the Indian average. The total erosion rate (973 t km−2yr−1) is 1.7 times greater than that of the Ganges. Upstream the Yamuna removes 1.04 mm yr−1 of the basin surface; the removal rate decreases downstream to 0.19 mm yr−1 at Allahabad, the point of confluence with the Ganges.
Aquatic chemistry is becoming both a rewarding and substantial area of inquiry and is drawing many prominent scientists to its fold. Its literature has changed from a compilation of compositional tables to studies of the chemical reactions occurring within the aquatic environments. But more than this is the recognition that human society in part is determining the nature of aquatic systems. Since rivers deliver to the world ocean most of its dissolved and particulate components, the interactions of these two sets of waters determine the vitality of our coastal waters. This significant vol ume provides not only an introduction to the dynamics of aquatic chem istries but also identifies those materials that jeopardize the resources of both the marine and fluvial domains. Its very title provides its emphasis but clearly not its breadth in considering natural processes. The book will be of great value to those environmental scientists who are dedicated to keeping the resources of the hydrosphere renewable. As the size of the world population becomes larger in the near future and as the uses of materials and energy show parallel increases, the rivers and oceans must be considered as a resource to accept some of the wastes of society. The ability of these waters and the sediments below them to accommodate wastes must be assessed continually. The key questions relate to the capacities of aqueous systems to carry one or more pollutants.
The behavior of heavy metals in a natural aqueous system is attracting researchers because of environmental issues. Man's activities have increased the quantity and distribution of heavy metals in the atmosphere, on the land, and in rivers, lakes, and seas. The extent of this widespread contamination has caused concern about its possible effects on plants, animals and human beings. One of the first steps in any systematic study of the aquatic chemistry of a potential contaminant is an elucidation of the principal modes of transport and sinks for the contaminant. It appears that a large proportion of the metallic substances discharged into water bodies is ultimately incorporated into sediments. (Warren, L. J., and others). The sediment is a complex mixture with three main components: clays, organic matter, and oxides of iron and manganese. While the role of clays and biota in affecting the transport of heavy metals is commonly recognized, the significance of Fe and Mn among the factors that are involved is frequently overlooked. It has been shown by Goldberg and later by Subramanian that the amounts of trace metals in seawater sediments are proportional to the iron or manganese content of the sediments. The observations by Mortimer, Hutchinson and others that oxidized sediments have much greater adsorptive powers than the reduced sediments led support to the idea that Fe and Mn play a significant role in influencing the distribution and the transport of a variety of metal ions of both the naturally occurring and polluted kinds. The ability of the metallic hydroxide coatings to act as sinks for various heavy metals is well known (Turekian and Scott,”; Martin et al.,Carpenter et al., Robinson, G. D. and many others); these sinks are comparable to the ferro‐manganese nodules in marine environment. These hydroxides and oxides readily sorb or coprecipitate cations and anions; even a low percentage of Fe (OH)3 and MnO2 has a controlling influence on the heavy metal distribution in aquatic system. That, Fe and Mn hydrons oxides are efficient scavengors of heavy metals, is shown by Goldberg; Jenne;Gibbs; Filipek et al.; Harrison et al. and others. Experimental studies on sorption/coprecipitation of heavy metals on/with hydrons iron and/or manganese oxides have been reported by many researchers (Morgam and Stumm;Posselt et al.; Guy et al.; Longanathan et al.; Davis and Leckie; Irone and Munemori, Singh and Subramanian; Oakley et al. 1981; and others). This incorporation of heavy metals into hydrons iron and manganese‐oxide can be due to adsorption (Specific or electrostatic), ion‐exchange or coprecipitation. Loganathan and Burean (1973), Subramanian (1976) and Burns (1976) proposed that the heavy metal ions are structurally bound in bydrous oxides of iron and manganese. The sorption of heavy metals by hydrous iron and manganese oxides is dependent on pH, ionic strength, metal concentrations etc. Benjamin and Leckie (1981) proposed an adsorption model for metals according to which adsorption mode is highly pH‐dependent, the complex species dominates metal adsorption at low pH and the free metal is dominant at high pH. The low solubility of hydrous Fe and Mn oxides together with their Iavege surface area approximately 300 m/g, i.e., small grain size (of the order of 100 A) and favorable surface change in the pH range generally found in natural aquatic systems make these hydrous oxides an efficient scavenger of heavy metals. Practical application of the sorption ability of hydrous metal oxides has been made in water and wastewater treatment, particularly by the use of iron and aluminium salts for the removal of phosphorous compounds, organic contaminants and heavy metals. Coagulation as practiced in water treatment is brought about by metal ion hydrolysis species and not by free multivalent metal ions (Matijevic et al., 1961). Once the metal reaches the sediment it is not necessarily thereby fixed for all time, but may be recycled via biological and chemical agents, both within the sedimentary compartment and also back into the water column. The extent of recycling or remobilization has an important bearing on the environmental significance of heavy metals in sediments.
Samples representing yearly averages of material transported by the Amazon and Yukon Rivers were analyzed to separate the transition metals (Cr, Mn, Fe, Co, Ni, and Cu) into the following transport phases: (1) crystalline particles, (2) metal hydroxide coatings, (3) solid organic material, (4) sorbed material, and (5) those in solution. The major transport phases are crystalline particles and metal hydroxide coatings, which, combined, carry 65% to 92% of the transition metals transported. Solid organic material, the next most important phase, transports between 5% and 19% of the total transported. Material carried in solution transports 0.6% to 17% of the total transported. Sorbed transition metals account for between 0.02% and 8% of the total transported. Metal hydroxide coatings represent the major transporting mechanism potentially available to organisms, since, for the Amazon and Yukon Rivers, respectively, 87% and 78% of the Fe, 69% and 73% of the Mn, and 71% and 69% of the Ni are transported in this form. Comparing the concentrations of transition metals carried to the oceans with the concentrations on the continents, a high Cu ratio (5 to 7) indicates continental depletion or river output enrichment; a moderate ratio (1.1 to 1.7) for Ni, Co, and Cr indicates intermediate depletion or enrichment, and a near-unity ratio for Fe and Mn indicates little depletion or enrichment. The sediments transport >97% of the total mass of transition metals to the world's oceans.
Suspended sediments collected from some major rivers of India — Ganges, Brahmaputra, Mahanadi, Godavari, Krishna, Cauvery, Narmada and Tapti — were studied to ascertain the nature of the particulate input of the Bay of Bengal and the Arabian Sea. Earlier reports on the mineralogy of bed sediments in these two bordering seas broadly agree with the present observations on continental input. Any discrepancy may be due to lack of data on particulates in these oceans. A combination of longshore dispersal and grain-size-controlled differential settling are suggested as possible mechanisms of distribution of continental input into these oceans.
Bulk chemistry of the Godavari river sediments consists mostly (75%) by four elements, Al, Si, Ca and Fe, which range from a factor (max./min. ratio) of 3 (Al, Si) to 172 (Ca). During the monsoon season, enrichment of Mg, Al, Si, Pb, Th and U and depletion of K and Mg are noticed at most of the locations. Mean composition indicated that Al, Si and Fe are depleted and Mg is enriched towards the river mouth, while Ti and Mn are almost constant. Sediments from the tributaries draining through Tertiary volcanics are relatively high in Fe, Mn, Cr, Ni, Cu and Zn and low in Al, Ca and Mg, whereas Si is high in sediments of the granitic terrain. Compared to the Indian mean value, the Godavari sediments are enriched in heavy metals and depleted in Al and K. Annual sediment transport, 170·106 tonnes (555 t km−2), consists mostly (99.5%) of Si, Ca, Al, Fe, Mg, Ti and K, with transport rates of 261, 93, 57, 33, 16, 8 and 5 t km−2, respectively. Such temporal and spatial variations in sediment chemistry over intermediate-size basin emphasize the need for re-evaluation of global means.
Two hundred twenty-seven stream sediment samples from a sixty-five square mile area of native copper occurrences near South Mountain, Pennsylvania, were collected and analyzed spectrometrically for copper content as part of a regional prospecting program.To enhance the recognition of meaningful anomalies, i.e., those likely to reflect the geographical locations of ore bodies, a technique for selectively simulating the effects of certain interfering factors was developed and applied to the trace metal data.Quantitative models were constructed to estimate the expression of 1. cultural features, 2. known faults, 3. metabasaltic rocks, and 4. existing prospects and workings in the regional copper distribution. The simulated influences of these factors were then removed from the original data to increase the relevance of residual copper anomalies to prospective metal sources.It was observed that the cultural features model removed a number of the original anomalies from the copper geochemical landscape. It was also noted that the effects of metabasalt were more strongly reflected in the stream sediment copper concentrations than those of faults, although previous authors have proposed fault control as an explanation for the local native copper occurrences.The procedure, which is described in detail, provides an "a priori" method for dealing objectively with the effects of specified factors on regional trace metal patterns.By increasing the likelihood of association between the geochemical data and the potential locations of mineral deposits, its utility as a prospecting tool is improved.
An estimate of average river particulate matter (RPM) composition was bàsed on analyses of more than 40 elements in the Amazon, Congo, Ganges, Magdalena, Mekong, Parana and Orinoco rivers, to which were added literature data for 13 other major world rivers, covering the whole spectrum of morphoclimatic features. Geographic variations of major elements in RPM are mostly linked to weathering types and to the balance between weathering rate and river transport. As a result of chemical erosion, Al, Fe and Ti are enriched in RPM with respect to the average parent rock, while Na, Ca, Mg and Sr are strongly depleted. These figures are directly related to the relative importance of dissolved and particulate transport in rivers; this has been computed for each of 40 elements. In order to study weathering on a global scale, the total observed elemental fluxes (dissolved + particulate) have been computed and compared to theoretical ones. The latter were derived from the elemental content in the average parent rock and the total quantity of weathered material, computed from the Al ratio in RPM and in parent rock. Observed and theoretical fluxes are balanced for the less mobilized elements (rare earths, Co, Cr, Cs, Fe, Mn, Rb, Si, Th, Ti, U and V) for which no enrichment relative to Al is noted in RPM, and for B, Ba, Ca, K, Mg, Na, Sr which are relatively depleted in RPM due to their high dissolved transport. Additional fluxes have been found for Br, Sb, Pb, Cu, Mo, Zn and are possible also for Ni and P. This is reflected by marked enrichments in RPM relative to Al for the poorly or moderately dissolved transports (Pb, Cu, Zn). Several hypotheses involving either the natural origin (volcanic dust, marine aerosols, geochemical fractionation) or the artificial origin (worldwide pollution) are discussed to explain these discrepancies, assuming river transport and weathering either to be in a steady state on a global scale or not. However, none of them can fully account for these additional fluxes. It is most likely that these excesses have multiple origins, anthropogenic or natural or both. The comparison between RPM and deep-sea clay compositions emphasizes the prime influence of river input on oceanic sedimentation of Si, Al, Fe, Ti, lanthanides, Sc, Rb, V, etc. A few elements such as Zn, Sb, occur in excess in RPM as compared to deep-sea clays; in order to balance this excess, a remobilization of these elements out of the sediment can be considered. Finally, the enrichment of Co, Cu, Mn and Ni in deep-sea clays compared to RPM is discussed and attributed to several sources and processes.
A procedure is developed to determine the mass absorption corrections in energy-dispersive X-ray fluorescence of samples with widely varying matrix composition and thickness, using the incoherently and coherently scattered radiation peaks in the recorded spectrum. For low atomic number elements both the coherent-to-incoherent scatter ratio and the absorption coefficient (e.g., at 2.956 keV, the Ar Kα energy) vary similarly with Z. After experimental calibration with known targets the scatter intensity ratio (corrected for the high-Z elements contribution via their characteristic X-ray peaks) allows evaluation of μ(2.956 keV) for the low-Z matrix fraction. For other energies, an interpolation is made between the in μ-in E curves of two adjacent low-Z elements whose μ(2.956 keV) values encompass the experimental value. The high-Z element absorption contribution is then added, in proportion to their characteristic peak intensity, to construct the complete absorption curve. A computer routine has been developed to carry out this procedure. Also the target thickness can straightforwardly be calculated through the information contained in the scatter peaks. Hence the total absorption correction can be obtained for samples of various and even somewhat heterogeneous thickness. A precision of 5% or better Is typically achieved for determinations of μ(2.956 keV) for sample thicknesses above 1.5 mg cm-2.
Sediments of the Wabigoon River, Ontario, are polluted with Hg from an industrial source at Dryden. Downstream from Dryden the river flows first through Clay Lake and then through Ball Lake. Hg, Cu, Zn, Cd and Fe concentrations in sediments of both lakes are correlated with organic C, but Hg content per unit concentration of organic C is higher, and increases more steeply with Organic C, in Clay Lake than in Ball Lake; in contrast, the Cu, Zn, Cd, and Fe concentrations per unit concentration of organic C are nearly the same in both lakes. These results substantiate the conclusion that the Hg originated at a point upstream from the lakes and tended to accumulate in Clay Lake on its way downstream, whereas the other metals were leached into the two lakes from diffuse sources in the surrounding terrain. Accumulation of river-borne organic pollutants in Clay Lake was also demonstrated. Application of the methods employed to the general problem of recognising and locating element anomalies is discussed.
Bed sediments were collected from the entire region of the Ganges basin and some parts of the Brahmaputra. In addition, selected
stations were sampled for suspended sediments as well. The samples were analysed for a number of heavy metals (Fe, Mn, Ni,
Cr, Cu, and Zn) by the thin-film energy dispersive X-ray fluorescence technique. There are pronounced temporal and spatial
variations in the heavy metals distributions. Suspended sediments are 5–10 times richer than the bed sediments. None of the
tributaries contribute significant heavy metal load, but around urban areas in Yamuna (tributary of Ganges), very high levels
due to the distribution from the drainage network are observed. Compared to the Brahmaputra, the distribution and fractionation
of heavy metals in the Ganges sediments are more erratic and highly variable. All the metals considered show high correlation
among themselves. Given the high flux of suspended sediments from the Himalayan rivers (nearly 20% of the global flux), the
worldwide budget for heavy metal transport may need to be suitably revised.
The scanning nuclear microprobe analytical facility of the IRMM was used to determine with PIXE major, minor and trace elements in individual giant marine aerosol particles, collected above the North Sea (particle size > 5 m ). The instrumentation is briefly described, and the experimental parameters chosen for these analyses are discussed. Elements with atomic numbers Z > 15 could be determined. Detection limits observed under the prevailing experimental conditions reached down to 50 fg in the case of Ti, V or Cr, corresponding to a mass content of 10 g/g in particles of 15 m size. Quantitative evaluation of the acquired spectra revealed basically three aerosol types in these samples: sea salt particles, sea salt combined with high contents of S, K and Ca, and particles rich in heavier elements (Ti, Cr, Fe, Ni). The agglomeration of several large particles forming a giant one could be visualised directly through the heterogeneity found in the elemental maps of such a particle.
Factors that govern heavy metal concentration in sediments were examined by a combined analytical, geochemical, and geological approach. The constrains encountered in the determination of the anthropogenic influence are exposed. The region examined was the Krka River estuary located in the typical karst region of the eastern Adriatic, Yugoslavia.
Sedimentological research revealed that: the Krka River (main water supplier) is almost free of suspended terrigenous material; the main supplier of suspended terrigenous matter of flysch origin is a small torrent-type Guduča Creek, and that this fine grained terrigenous material is sedimented mostly in the central enlarged part of the estuary, the Prokljan “Lake.”
Three different groups of heavy metals were identified in recent sediments. Increased concentrations of nickel and zinc were found in estuarine sediments due to strongnatural enrichment in source rocks. Manganese and chromium were found to benaturally enriched and depleted in surface layer respectively, due to the different postdepositional geochemical behavior. Lead and copper concentrations were found to be increased in surface sediments in the central part of the estuary, apparently from anthropogenic source.
Experimental data for sorption of Hg, Cd, Cu, and Pb by sand, silt, and organic-rich sediments from the Ottawa River, Canada
show significant conformity to Langmuir's equation. Values of the bonding energy constant and the sorption maximum correlate
directly with organic content and mean grain size (φ). Desorption experiments indicate that the heavy metals form stable complexes
in nitrilotriacetate (NTA) and NaCl Solutions, with the following desorption ratios: Hg, 1:1 (Cl−:NTA); Pb, 1:10; Cd, 1:2. Serial and batch desorption studies under various conditions show that the cation-exchange order
in the sediments is Hg>Pb>Cu>Cd. For a given heavy metal the partition coefficient between sediment and solution is not greatly
changed by the presence of another cation, provided the latter has the same order of concentration. If, the concentration
of one cation exceeds another by more than 10, however, significant desorption of the less concentrated ion takes place on
a mass action basis.
Tabulations are given for total dissolved trace metal concentrations in the Var and the Roya, two rivers containing relatively little pollution, which enter the North Mediterranean. Means and standard deviations were as follows. For the Var Cu was 240 140 ng L–1, Zn 122 16 ng L–1, Cd 30.7 4.9 ng L–1, and Pb 111 68 ng L–1. For the Roya corresponding values were Cu 284 98 ng L–1, Zn 87 14 ng L–1, Cd 74 57 ng L–1, and Pb 80 48 ng L–1, These values are lower than expected from stuidies reported in the literature, but probably are explained by the limestone environment. Values are also tabulated for the content in the suspended matter and sediments. The Var and the Roya differed in the amount of complexed metals, the percentage being much higher for the Roya. These regional background results are important for assessment of possible pollution in future.
Selective chemical attack has been used to separate recent surface marine sediments into organic, non-detrital and detrital components, and the concentrations of iron, manganese, copper and zinc in each fraction determined. The non-detrital fraction controlled the overall elemental concentrations and relationships apparent in the bulk sediment, particularly in the cases of copper, manganese and zinc. Copper was found associated with the organic fraction. The predominant processes of primary deposition are precipitation of hydrated ferric oxide and adsorption of copper and zinc onto this material.
Based on preliminary investigations, over the period of two years, the chemical quality of the Ganges, Indus, Brahmaputra, Narmada, Tapti, Mahanadi, Godavari, Krishna, Tungabadra and Cauvery rivers have been evaluated. The discharge-weighted composition for Indian rivers has been calculated and compared to the world average river water. The Indian rivers are alkaline and about 25% more concentrated in dissolved salts than the world average. Discharge and downstream variations in the water chemistry for a few selected stations are briefly explained. The range of values for suspended sediments transported by the rivers are shown together with limited seasonal, discharge and downstream variations. Chemical, sediment and total load have been calculated for Indian rivers and erosion rates are compared to data for some major world rivers.The chemical data of river waters have been used to predict theoretically the mineral assemblages in carbonate and silicate systems. Preliminary studies, using X-ray diffraction, have been made on the suspended sediments and the results are compared to theoretical predictions based on water chemistry.
The origins, nature and degree of contamination of freshwater and marine sediments by lead, zinc and cadmium are discussed. Consideration is given to what is known about the formation and composition of natural sediments and the pathways by which heavy metals are eventually incorporated into such sediments. The effects of the additional flux of heavy metals resulting from man's activities are then assessed.
River sediments from all of the major drainage basins (except the Indus) in the Indian sub-continent were collected and analysed by thin-film X-ray fluorescence technique (XRF) to determine their chemical composition.On the basis of analysis of more than 120 samples, average chemical compositions of river-borne sediments from the Indian sub-continent have been calculated. Also, average concentration values for sediments from each of the river basins, and the sub-continent average and the inter-basin differences are discussed in relation to weathering processes in the drainage basins. Comparisons have been made with the chemistry of sediments from the Bay of Bengal (which receives the bulk of sediments delivered by Indian rivers). Our observations are discussed in the light of average chemical composition of world-river sediments and the world surface rock exposed for continental weathering.
A multivariate statistical evaluation technique, non-linear mapping, is proposed to extract information from a multielement microbeam proton-induced X-ray emission data set. Individual aerosol particles, collected in the North Sea troposphere, were classified according to their composition. Several groups of particles were identified and suggestions were made for their sources.
For any time period, total basin sediment yield can be used to make reliable estimates of upland erosion rates only when no significant change in sediment storage is in progress. In the case of Coon Creek, almost 50 percent of human-induced sediment has historically gone into floodplain storage and less than 7 percent has left the basin. However, some of the stored sediment is becoming mobile, and the present yield per unit area may actually be increasing downstream with the augmentation coming from the storage loss.
Geochemistry of the Ganga River basin
- Abbas
Abbas, N., 1985. Geochemistry of the Ganga River basin. Ph.D thesis, Jawaharlal Nehru University, New Delhi, 184 pp.
Potential for metal mobilization by synthetic organic chelating agents — a case study
- Allan
Allan, H.E., 1983. Potential for metal mobilization by synthetic organic chelating agents --a case study. In: Proc, Int. Conf. Heavy Metals in the Environment, Heidelberg. CEP Consultants Ltd, Edinburgh, Vol.
Soils of Uttar Pradesh
- Mehrotra
Mehrotra, C.L., 1972. Soils of Uttar Pradesh. In: T.M. Alexender (Ed.), Soils of India. The Fertilizer Association of India, pp. 278-296.
A study on water quality in the River Yamuna around Delhi
- V Subramanian
- R Sitasawad
Subramanian, V. and R. Sitasawad, 1984. A study on water quality in the River Yamuna around Delhi, India. Water Qual. Bull., 9: 219-222.
Analytical studies of Mussoorie phos-phorite
- M N Mehrotra
- R K Yadav
- B N Mehrotra
Mehrotra, M.N., R.K. Yadav and B.N. Mehrotra, 1981. Analytical studies of Mussoorie phos-phorite. Neues Jahrb. Mineral., Abh., 142: 139-148.
Nature of Chemical and Sediment load in the Yamuna River Basin
- Jha
Jha, P.K., 1986. Nature of Chemical and Sediment load in the Yamuna River Basin. Ph.D thesis. Jawaharlal Nehru University, New Delhi, 207 pp.
Description and analyses of eight new USGS rock standards
- Flanagan
Flanagan, F.J., 1976. Description and analyses of eight new USGS rock standards. U.S., Geol. Surv., Prof. Pap., 840: 192-220.
Coster Dantas and H. Silveria Dantas, 1979. Thin film and X-ray fluorescence technique
- Van Grieken
- L Van
- C Dack
Van Grieken, R., L. Van't Dack., C. Coster Dantas and H. Silveria Dantas, 1979. Thin film and X-ray fluorescence technique. Anal. Chim. Acta, 108: 93-101.
The Yamuna sub-basin Central Board for the Prevention and Control of Water Pollution
- ~1 Cbcwp
CBCWP, 1980~1. The Yamuna sub-basin (April 1977-December 1978). Central Board for the Prevention and Control of Water Pollution, New Delhi, 114 pp.
Physiographic and anthropogenic controls of global and regional ionic runoff
- Aurada
Aurada, K.D., 1983. Physiographic and anthropogenic controls of global and regional ionic runoff.
Dissolved Loads of Rivers and Surface Water Quantity/Quality Relation-ship Elemental composition of Godavari sediments (central and southern Indian subcontinent) Composition of Narmada and Tapti estuarine particles
- G Biksham
- V Subramanian
In: B.W. Webb (Ed.), Dissolved Loads of Rivers and Surface Water Quantity/Quality Relation-ship. Proc. Syrup., Hamburg, IAHS Publ. No. 141. pp. 31-39. Biksham, G. and V. Subramanian, 1988. Elemental composition of Godavari sediments (central and southern Indian subcontinent). Chem. Geol., 70: 270~286. Borole, D.V., M.M. Sarin and M. Somayajulu, 1982. Composition of Narmada and Tapti estuarine particles. Indian J. Mar. Sci., 11: 51-62.
Enrichment of metals in a fresh water reservoir acidified by geochemical loading
- Aulio
Aulio, K., 1987. Enrichment of metals in a fresh water reservoir acidified by geochemical loading.