Informatics Publishing Limited

P. Kasinatha Pandian ¹, K. Dharanirajan ²

Affiliations
1 Institute of Remote Sensing, Anna university, Chennai 600 025, IN
2 Institute for Ocean Management, Anna University, IN

Abstract

Baseline information on the beach morphology along the Ennore coast, an industrial hotspot region in the East coast of Bay of Bengal, is presented. In order to assess the effect of human interference on the coastal zone, a baseline survey of the coastline is considered important. Such information enables to predict the future coastal morphology and settings. Based on the baseline data created, this study predicts that the accretion noticed in the southern side of the Ennore port will affect the port entrance channel in the future course. Therefore it warrants for immediate mitigation measures to curtail such accretion and also recommends for keeping the Ennore creek mouth open permanently. Ennore creek also serves as the coolant source for the two thermal power plant units. The study also put forward certain other mitigation measures which are relevant in the present event of developments. Adjacent to Pulicat Lake, the erosion is continuously taking place at an alarming rate making vulnerable for a striking storm to wash away the villages under the sea. It may also lead to the merger of the Pulicat Lake into the Bay of Bengal, thereby the brackish water ecosystem of the lake may altogether disappear causing several ecological and social problems. The study concludes that a long-term integrated coastal monitoring is the need of the hour.

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E. Yuvaraj ¹, K. Dharanirajan ¹, Saravanan ¹, G. Narshimulu ¹

Affiliations
1 Department of Disaster Management, Pondicherry University, Port Blair 744 112, IN

Abstract

Disasters are the events which devastate human lives, properties and natural ecosystems; cyclones are frequent events in tropical countries which have adverse impacts on coastal areas. The present study evaluates the impact of cyclone Lehar post-disaster in the South Andaman Island using geographic information system (GIS) and remote sensing techniques. Cyclone Lehar originated in the Andaman Sea and had a major impact on the South Andaman Island. Digital elevation model was used to create elevation and slope maps of the study area. These maps were used to study the impacts of floods, landslides, storm surges and runoff. Land-use and land-cover features were mapped and overlaid with this model for preparing the vulnerability map for various outcomes of the cyclone. Preliminary impact assessments were made in these identified vulnerable areas and also throughout the study area. Finally the results were interpreted with vulnerability map prepared using the GIS technique which shows that most of the affected areas are correlated with the vulnerability map. Cyclone Lehar had adverse impacts on natural ecosystems such as forests, mangroves and sandy beaches. It also damaged manmade features such as settlements, infrastructure, agricultural fields and plantations. This study proves spatial technologies are the indispensible tools for post-disaster planning and impact assessment.

Keywords

Cyclones, Impact Assessment, Post-Disaster Planning, Spatial Technologies.

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M. Suresh ¹, B. Gurugnanam ¹, S. Vasudevan ², K. Dharanirajan ³, N. Jawahar Raj ⁴

Affiliations
1 Department of Earth Sciences, Annamalai University, Annamalai Nagar - 608 002, IN
2 CGIT, School of Geosiences, Bharathidasan University, Tiruchirappalli - 620 024, IN
3 Department of Ocean Sciences and Marine Geology, Pondicherry University, Andaman, IN
4 Department of Geology, National College, Trichy, Tiruchirappalli - 620 001, IN

Abstract

In the present study, the chemical characteristics of groundwater with respect to drinking and Irrigation water quality in upper Thirumanimuthar sub-basin, Cauvery River, have been studied. 51 groundwater samples were collected and analysed for pH, conductance, total dissolved solids, total hardness, calcium, magnesium, carbonate, bicarbonate, total alkalinity, chloride, sodium, potassium, sulphate etc. The values analyzed were evaluated in detail and compared with WHO water quality standards. It is observed that, for most of the groundwater quality parameters, the values are not potable for drinking and irrigational use. To understand the spatial distribution of unsuitable zones, ArcGIS was employed. Attributes were linked and spatial interpolation mapping was done. Inverse distance weighted interpolation technique was followed for raster and vector mapping. Finally the overlay analyses were also carried out to locate the worst quality zone.

Keywords

SAR, Sodium Percentage, GIS, Spatial Distribution Map, Overlay Analysis, Cauvery River, Tamil Nadu.

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M. Suresh ¹, B. Gurugnanam ¹, S. Vasudevan ², B. Rajeshkanna ², K. Dharanirajan ³, N. Prabhakaran ¹

Affiliations
1 Geographic Information Technology Lab, Department of Earth Sciences, Annamalai University, Annamalai Nagar, Tamil Nadu, IN
2 Centre for Geographic Information Technologies, Bharathidasan University, Trichy, Tamil Nadu, IN
3 Department of Ocean Studies, Pondicherry University, Andaman, IN

Abstract

In the present paper deals with the study of hydrogeochemistry of groundwater by multivariate statistical techniques such as factor and cluster analyses. The upper Thirumanimuthar sub-basin, Cauvery River, hard rock terrain in Salem District covering an area of about 346.40 km2 has been selected for the study. Fifty one samples were collected during premonsoon season 2007 and analysed for various water quality parameters like pH, EC, TDS, Ca, Mg, Na, K, HCO₃, CO₃, SO₄, Cl and TH. Hydrogeochemical data of 51 groundwater samples were subjected to Q- and R- mode factor and cluster analysis. R-mode analysis reveals the interrelations among the variables studied and the Q-mode analysis reveals the interrelations among the samples studied. The R-mode factor analysis shows that Na and CI with HCO₃ account for most of the electrical conductivity and total dissolved solids of the groundwater. The 'single dominance' nature of the majority of the factors in the R-mode analysis indicates non-mixing or partial mixing of different types of groundwaters. Both Q-mode factor and R-mode cluster analyses show that there is an exchange between the river water and adjacent groundwater. Cluster classification map reveals that 97.79% of the study area comes under cluster I classification.

Keywords

Groundwater, Hydrogeochemical Studies, Multivariate Statistical Analysis, Factor Analysis, Cluster Analysis.

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B. Gurugnanam ¹, M. Suganya ¹, M. Suresh ¹, K. Dharanirajan ²

Affiliations
1 Department of Earth Sciences, Annamalai University, Annamalai Nagar-608 002, T.N., IN
2 Institute for Ocean Management, Anna University, Chennai, T.N., IN

Abstract

Geochemical analysis of groundwater is employed to evaluate the postmonsoon 2005 water quality of upper Thirumanimuthar subbasin. Thirty two representative groundwater samples were collected from dug and bore wells. The samples were analysed to monitor the water chemistry of major ions. The results were evaluated in detailed and compared with WHO water quality standards. An overall assessment of the water samples indicated that all parameters are within the permissible limit except in some locations. According to the USSL diagram most of the samples falls in C₃-S₁ class, which indicates its suitable nature. Piper trilinear diagram interpretations were made to know the chemical type of the groundwater. It reveals that the subsurface water is alkaline earth (Ca+Mg) exceeds alkalies (Na+K) type.

Keywords

Groundwater, Geochemical Studies, Piper Trilinear Diagram, Kalley’s Ratio, Sodium adsorption ratio, Magnesium Hazards, Sodium Percentage.

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