Search

Selected heavy metals (Cr, Co, Ni, Cu, Zn, As, and Pb) in sediments from Periyakalapattu to Parangipettai of east coast of Tamil Nadu were determined to assess the contamination status and potential ecological risk. The pollution indices such as enrichment factor (EF), contamination factor (CF), geoaccumulation index (Igeo), and pollution load index (PLI) were calculated to determine the contamination level and enrichment of metals in sediments. EF analysis suggested that anthropogenic influence on the environment has been significant in case of Cr. The values of CF indicate that the sediments are not contaminated with these heavy metals. Igeo results reveal that the study area is not contaminated with respect to Cr, Co, Ni, Cu, Zn, As, and Pb. This results of Igeo are in good agreement with PLI. Based on the sediment quality guidelines, it is observed that Cr and Ni would be a concern for the ecotoxicological risk in study area. [ABSTRACT FROM AUTHOR]

The present study area extends to 150 km from Mandapam to Tuticorin, Gulf of Mannar, Tamil Nadu. Before the commencement of sample collection, a base map in the scale 1: 50,000 was prepared using the toposheet nos. 58L/13, 58L/1 and 58M/16. The fieldwork was done during the month of March, 2006. A total of 74 sediment samples were collected from beach (6), offshore (46) and estuarine (22) in the study region. The offshore samples were collected at six transects keeping the stations at Mandapam (5 nos.), Valinokkam (5 nos.), Vaippar (5 nos.), Vembar (5 nos.), Kallar (5 nos.), Tuticorin (5 nos.), off Tamiraparani (10 nos.) and Punnaikayal (6 nos.). [ABSTRACT FROM AUTHOR]

Groundwater is an important source of water supply throughout the world. It is very essential for irrigation industries and domestic purposes. It is a good source of freshwater available on the earth. It is an important renewable resource having several inherent advantages over surface water. Its wide distribution, negligible evaporation loss and low risk of contamination are considered as important qualities. Fifty-seven groundwater samples were collected from the Singipuram river basin of Salem district from shallow bore wells and open wells to maintain uniformity, to asses the quality and its suitability for domestic and irrigation purposes. Geologically, charnockites and gneisses constitute the country rocks of the study area. The weathering of host rocks and agricultural activities play an important role in modifying the chemistry of groundwater. The quality of the groundwater in the southern part of the area is far from satisfactory and needs careful management. Five broad types have been identified, which are Ca-Cl, Ca-Na-Cl, Ca-Na-HCO3, Ca-Na-HCO3-Cl and Na-HCO3-Cl. The salinity of Sodium Absorption Ratio (SAR), Residual Sodium Carbonate (RSC) and permeability index indicate that most of the groundwater samples are suitable for irrigation. [ABSTRACT FROM AUTHOR]

In order to identify the nature of sediment character, mode of deposition in river, estuary and marine regions of Tamiraparani and adjoining coastal areas, grain size and ecological parameter studies for both the monsoons were carried out. The sampling sites were determined with a grid overlain on a Survey of India 1:50,000 scale base map of Tamiraparani estuary and adjoining coastal area. Ninety sediment samples were collected in two seasons using Van Veen grab sampler. The Organic Matter (OM) in the estuarine environment ranged from 0.3% to 4.7%. Calcium carbonate content in the surface sediments was generally low. A strong positive association was found with fine sediments and organic matter (R2 = 0.0602) in pre-monsoon and (R2 = 0.0889) post-monsoon respectively. Tamiraparani river samples indicated a unimodal and bimodal distribution in pre-monsoon. In Tuticorin, marine samples were also bimodal in nature with medium and fine sand where sediment was additionally deposited by the Tamiraparani river. Based on the sediment texture and ecological studies, it was clearly observed that in pre-monsoon, the erosional activities were predominant than in post-monsoon. In both the monsoons, sediments were transported from river and estuary towards the beach and marine. In pre-monsoon, whatever sediment deposited was transported and shifted due to longshore current action. But in the post-monsoon, depositional environment, where the sediments deposited due to multisource like riverine and marine influence, was observed. [ABSTRACT FROM AUTHOR]

In this data, the heavy metal concentration and magnetic susceptibility in coastal sediment samples collected from Periyakalapet to Parangaipettai of East Coast of Tamilnadu using Energy Dispersive X-ray Fluorescence (EDXRF) technique and dual frequency susceptibility meter. We aimed to (i) determine the heavy metal concentration in the sediments from Periyakalapet to Parangaipettai of East Coast of Tamilnadu (ii) assess the magnetic mineral property of sediments (iii) study the correlation between heavy metal and magnetic susceptibility. The determined heavy metal concentration found in the order of Mn> Ba > V > Cr > Zn > La > Ni >Pb> Co > As > Cd > Cu > Al > Fe >Ca> Ti > K > Mg. The magnetic susceptibility (χ lf ) measurements show that they vary from 5.92×10 -8  m 3  kg -1 to 29.06×10 -8  m 3  kg -1 with an average of 20.39×10 -8  m 3  kg -1 . Analysed data confirmed that magnetic susceptibility has the potential tool to indicate the heavy metal pollution sources.