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Senapathi VENKATRAMANAN Sang-yong CHUNG Thirunavukkarasu RAMKUMAR Gopalakrishnan GNANACHANDRASAMY Tae Hyung KIM 《国际泥沙研究》2015,(1):28-38
The purpose of this study was to assess the chemical partitioning of selected heavy metals(Fe,Mn,Cu,Zn,Pb,Cr,Co and Ni) in 10 surface sediments at Tirumalairajan River Estuary in the southeastern coast of India.A five-step sequential extraction technique was used to assess the environmental status of heavy metals.Most of metals were considered to be immobile due to the high availability in the residual fraction of heavy metals.The sediments of Tirumalairajan River estuary had not been polluted by heavy metals,and they didn’t pose any high ecological risk.The seasonal variations of heavy metals were slightly higher in summer than in monsoon season.Factor analysis was also carned out to understand the associations of metals in different fractions with sand,silt,clay,organic matter,pH,salinity and other metals.The relationship between the Q-mode and R-mode cluster analyses was useful for identifying the pollution levels in both seasons.It was proved that the enrichment of heavy metals was related with geogenic and anthropogenic sources.The information on total metal concentrations in sediments was not sufficient for assessing the metal behavior in the environment,but the sequential extraction technique was more effective in estimating the environmental impact of contaminated sediments. 相似文献
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Sang Yong Chung Venkatramanan Senapathi Kye Hyun Park Joo Hyeong Son Selvam Sekar 《Arabian Journal of Geosciences》2018,11(24):769
Ulsan mine produced the iron ore minerals of magnetite, arsenopyrite, and scheelite in 1992, and serpentine was developed from 1977 to 2002. The soils of the mine were contaminated by heavy metals such as As, Zn, Ni, and Cd. Heavy metals of Ni and Zn came mostly from serpentinite, and As was derived mainly from arsenopyrite in the scan-type iron ore body. As, Zn, and Ni were major contaminants, but Cd was a minor contaminant on a basis of Korean standard. The heavy metals in the deep depth (>?5 m) came from the host rocks, and those in the shallow depth (<?5 m) were derived from the organic–mineral complexation soil. The remediation plan was a soil washing for highly contaminated soils and the containment of clay materials for less contaminated soils. Even though the remediation methods were successful, the continuous monitoring and the analysis of monitoring data are still necessary for the conservation of soil and groundwater around the study area. 相似文献
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Thirunavukkarasu Ramkumar Senapathi Venkatramanan Irudhayanathan Anithamary Sheik Mohamed Syed Ibrahim 《Arabian Journal of Geosciences》2013,6(1):101-108
A study was conducted to evaluate the water quality of Kottur block, Thiruvarur district, Tamilnadu. Groundwater samples from hand pumps and tube wells of 16 stations were analyzed during postmonsoon and premonsoon (2008) with the help of standard methods of APHA (1995). Dominance of cations are in the following order Na>Ca>K>Mg and Cl>SO4>HCO3>NO3 by anions in both the seasons. The analytical results shows higher concentration of total dissolved solids, electrical conductivity, sodium, chloride, and sulfate which indicate signs of deterioration but values of pH, calcium, magnesium, and nitrate are within permissible limit as per World Health Organization standards. From the Piper trilinear diagram, it is observed that the majority of groundwater samples are Na-Cl and Ca-Mg-SO4 facies clearly indicates seawater incursion. In Wilcox diagram, most of the samples fall in low to very high sodium hazard and low to very high salinity hazard indicates moderately suitable for agricultural activities. Kelly’s ratio and magnesium ratio indicates most of the samples fall in suitable for irrigation purpose. 相似文献
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Senapathi VENKATRAMANAN Thirunavukkarasu RAMKUMAR Irudhayanathan ANITHAMARY Govindaraj RAMESH 《国际泥沙研究》2011,(4):460-470
The distribution of grain size parameters along 11 km stretch of the beach sediments between Karikal and Nagore,reveals that the mean grain size exhibits a marked decreasing trend on either side of the mouth of the Tirumalairajanar River which flow from west to east.The sediments are mainly of medium to coarse grained,moderately sorted,near-symmetrical skewed to fine skewed and leptokurtic to mesokurtic in nature.Interrelationship of various parameters shows bimodal nature of sediments having dominance of medium to coarse sand.The major part of the sediment fall in a coarse to fine grained category(sand and silt).Based on the CM(Coarser one percentile value in micron) pattern,the sediment fall in rolling and suspension field.These factors includes the sediments discharged from the river mixes with offshore sediments and with the sediments eroded from a source rock.The effect of wave sorting, and the northward drifting of sediments by littoral current are understandable.Results indicate that the Tirumalairajanar River is the most important source for modern sediments in the study area.The agitation by waves is an important sorting mechanism in the study area,and the net sediment transport in the study area is northward.The findings are based on the grain sizes and also corroborated by shortterm observations of the beach sediment dynamics and transport during the monsoon and summer seasons between Karaikal and Nagore region. 相似文献
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Senapathi Venkatramanan Thirunavukkarasu Ramkumar Irudhayanathan Anithamary Poovalinga Ganesh 《Arabian Journal of Geosciences》2013,6(6):1871-1881
Morphological mapping plays an essential role in understanding river processes. Evaluation of the morphological parameters requires preparation of basin, upstream and downstream, stream link, stream network, stream order, flow direction, flow accumulation, and digital elevation model, which help to understand the nature of the river. Assessments of morphological digital maps provide upstream and downstream flow rates, slope variation, sedimentation, and specific stream erosive power in river systems. The river patterns of the study area mainly controlled by geological nature. Therefore, this paper discusses conceptual foundations and illustrates how mapping approaches can be used to produce morphological information of Tirumalairajan river systems. 相似文献
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Senapathi Venkatramanan Thirunavukkarasu Ramkumar Irudhayanathan Anithamary 《Arabian Journal of Geosciences》2013,6(5):1371-1380
The aim of this study is to understand the various sources and factors controlling the abundance and distribution of clay minerals, sand, silt, clay and organic matter of the surface sediments of Tirumalairajanar Estuary in two different seasons. The study was undertaken for two seasons, based on ten selected stations all along the estuary, mouth and freshwater zone. Furthermore, along the estuary region, clay and silt were observed and also at few stations in the upstream end. Organic matters in the sediments appeared to be the main mechanisms for the distribution of clay minerals in estuary indicated that the distributions of clay minerals were comparatively higher during postmonsoon than in premonsoon season. The clay mineral assemblage consists mainly of chlorite, kaolinite, montmorillonite, illite and very scarce gibbsite. The clay from the sediments has been separated and studied for mineral identification using X-ray diffraction analysis. The present study also reveals that sediment texture is one of the main controlling factors for the distribution of organic matter. 相似文献
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Sang Yong Chung Venkatramanan Senapathi Selvam Sekar Tae Hyung Kim 《Hydrogeology Journal》2018,26(6):1875-1885
Monitoring and time-series analysis of the hydrological parameters electrical conductivity (EC), water pressure, precipitation and tide were carried out, to understand the characteristics of the parameter variations and their correlations at a coastal area in Busan, South Korea. The monitoring data were collected at a sharp interface between freshwater and saline water at the depth of 25 m below ground. Two well-logging profiles showed that seawater intrusion has largely expanded (progressed inland), and has greatly affected the groundwater quality in a coastal aquifer of tuffaceous sedimentary rock over a 9-year period. According to the time series analyses, the periodograms of the hydrological parameters present very similar trends to the power spectral densities (PSD) of the hydrological parameters. Autocorrelation functions (ACF) and partial autocorrelation functions (PACF) of the hydrological parameters were produced to evaluate their self-correlations. The ACFs of all hydrologic parameters showed very good correlation over the entire time lag, but the PACF revealed that the correlations were good only at time lag 1. Crosscorrelation functions (CCF) were used to evaluate the correlations between the hydrological parameters and the characteristics of seawater intrusion in the coastal aquifer system. The CCFs showed that EC had a close relationship with water pressure and precipitation rather than tide. The CCFs of water pressure with tide and precipitation were in inverse proportion, and the CCF of water pressure with precipitation was larger than that with tide. 相似文献
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