Assessment of shoreline changes over the Northern Tamil Nadu Coast,South India using WebGIS techniques

Coastal zone is often vulnerable to natural hazards such as cyclones, storm surges, tsunamis, erosion, accretion, and coastal flooding; and man-made hazards like ports, jetties, seawalls, breakwaters, and groins. These disasters are frequently affecting the shorelines, beaches, and headlands that lead to loss of human life, properties, and natural ecosystems. To prevent further loss in the coastal zone and to conserve the existing natural resources, it is important to map and monitor vulnerable shorelines at frequent time intervals. The current study, conducted over the Northern TN (Tamil Nadu) coast of India, is highly dynamic due to its nature of coast and shoreline changes. The temporal remote sensing data and Survey of India (SOI) topographic maps over the period of 40 years (i.e., 1976–2016) were used to capture shorelines and then the erosion and accretion from the shorelines were assessed by performing the overlay analysis. These geospatial datasets of shorelines were incorporated into WebGIS platform, which was developed and demonstrated using open source software. This latest WebGIS technology allows users to store a large volume of geospatial datasets in the server and access through internet with a web browser that lead to manipulation, visualization, interaction, and dissemination. The results revealed that there were 61 layers, which include district-wise shorelines, erosion, and accretion for Tiruvallur, Chennai, and Kanchipuram. These geospatial datasets in WebGIS showed that the dynamism on the morphological structure of the shorelines, over the Northern TN lost 1,925 ha and gained 1,578 ha due to erosion and accretion, respectively. It is reported that in this study spatial reduction in the coastline may be attributed to natural and anthropogenic activities. However, this research will be useful for various stakeholders, including coastal management authorities to formulate policies and to regulate the coastal development activities.     

Occurrence and seasonal variation of bacterial indicators of faecal pollution along Thoothukudi Coast, Tamil Nadu

Theprevalence and seasonal variation of bacterial indicators of faecal pollution such as total coliform bacteria, faecal coliform bacteria, Escherichia coli and faecal streptococci were investigated in samples of water and beach sand from the four fish landing centres of Thoothukudi. Further the samples were screened for Salmonella to study the reliability of faecal indicator bacteria as an index of human pathogenic bacteria. Total coliform bacteria, faecal coliform bacteria and Escherichia coli were isolated from all four landing centres from undetectable to the maximum detectable level of over Most Probable Number 140 throughout the year with no obvious seasonal variation. Faecal streptococci were also detected in most samples. There was no discernable relationship between faecal indicators and physical parameters. The relationship between faecal indicators and Salmonella was not significant (p > 0.05). The results showed that the coastal waters along Thoothukudi is polluted and presents a potential risk to public for recreational and fishing activities.     

Total and methyl mercury in small marine biota caught off the Coast of Chennai,India

Abstract

This study reports the concentrations of total mercury and methyl mercury in sixteen families of marine biota caught off the coast of Kasimedu in Chennai, India, an important but understudied fish landing region. These included the commonly caught croakers, carangids, rays, goat fish, anchovies, crabs, and prawns. There was no correlation between total mercury or methyl mercury with fish length or mass. All concentrations were lower than the Food Safety and Standards Authority of India limits (total mercury = 500?μg/kg; methyl mercury = 250?μg/kg). Some values were above screening levels (total mercury >40?μg/kg wet weight) when considering possible adverse effects in predatory fish that consume the analyzed biota.

Abbreviations: dw: dry weight; MeHg: methyl mercury; THg: total mercury; ww: wet weight     

Diversity and community structure of butterfly of Arignar Anna Zoological Park, Chennai, Tamil Nadu

Investigation was carried out on the diversity of butterfly fauna in selected localities of conservation and breeding center of Arignar Anna Zoological Park (AAZP), Chennai, Tamil Nadu. Atotal of 56 species were recorded, 15 of them belonged to Pieridae, 12 Nymphalidae, 9 Satyridae, 8 Papilionidae, 7 Danaidae, 3 Lycaenidae and 1 species each belonged to the families Acraeidae and Hesperidae. Qualitatively and quantitatively Pieridae family were comparatively dominant than that of other families. The notable addition to the 25 more species listed during this observation were compared to previous field survey. Comparison of butterfly species distribution between the different localities revealed that butterfly species richness was higher at mountain region with 52 species and lowest of 25 species at public visiting areas. Visitor's activities may be that reason for effects on butterfly distribution and lack of vegetation. Each five endemic and protected species (i.e. endangered) listed under the Wildlife (Protection)Act were highlighted greater conservation importances of the AAZP. It is suggest that butterfly species diversity generally increase with increase in vegetation and declines with the increase in disturbance.     

Organochlorine residues in the avifauna of Tamil Nadu (Southeast coast of India)

Pollution due to persistent pesticides is not a regional but a global problem. Organochlorine pesticides are persistent chemicals, stored and accumulated in the tissues of a wide variety of invertebrates and vertebrates including marine species. In the present study the organochlorine residues HCHs, DDTs and PCBs were measured in different trophic groups of birds (scavengers, inland piscivores, coastal piscivores, insectivores, granivores and omnivores) collected from Tamil Nadu Coast, India. The residue accumulation as a function of sex did not depict distinct variation. However, females had lower residue levels than males in terms of their mean weight and feeding habits. A continuous monitoring programme is recommended to establish the studied organisms as indicator species.     

Heavy metal accumulation in lichens growing in north side of Lucknow city, India

Accumulation of Pb, Fe, Cr, Zn, Cd, Ni, Cu and Hg metals in six common lichen species growing on Mangifera indica trees in mango orchard surrounding the north side of the Lucknow city, were analyzed. The study revealed the higher concentration of Pb (3.3 - 15.6 microgg(-1)), Cr (25.6 - 137.5 microgg(-1)), Zn (49.4 - 219.7 microgg(-1)), Cu (10.2 - 66.6 microgg(-1)) and Fe (1748 - 19374 microgg(-1)).     

Organochlorine residues in the avifauna of Tamil Nadu (Southeast coast of India)

Pollution due to persistent pesticides is not a regional but a global problem. Organochlorine pesticides are persistent chemicals, stored and accumulated in the tissues of a wide variety of invertebrates and vertebrates including marine species. In the present study the organochlorine residues HCHs, DDTs and PCBs were measured in different trophic groups of birds (scavengers, inland piscivores, coastal piscivores, insectivores, granivores and omnivores) collected from Tamil Nadu Coast, India. The residue accumulation as a function of sex did not depict distinct variation. However, females had lower residue levels than males in terms of their mean weight and feeding habits. A continuous monitoring programme is recommended to establish the studied organisms as indicator species.     

A study of Malaiyur village ecosystem of Madurai district, Tamil Nadu (India)

The interaction between man and environment in Malaiyur, a hilly village of Madurai District (Tamil Nadu) was studied during the year 1998. The village is sustained on agriculture labour and hence occupies the lowest hierarchy with traditional occupation and the people may be categorised as 'ecosystem people'. The study suggests that the people has to be changed as 'Biosphere people' to protect the environmental degradation due to human activities.     

Coastal community resilience: analysis of resilient elements in 3 districts of Tamil Nadu State, India

India has a long coastline of about 7,517 km. with 20% occupying the coastal area. Due to increase in population; people have been exploring the possibility of developmental opportunities in the coastal areas. Tsunami in 2004 was another unexpected natural catastrophe which badly affected many South Indian coastal states especially the state of Tamil Nadu. Coastal communities here are increasingly at risk from many chronic and episodic coastal hazards which threaten the health and stability of coastal ecosystems and communities. The degradation of the coastal environment from chronic human-induced actions threaten food security, livelihoods, the overall economic development and well being of coastal communities. Disasters big or small affecting the coastal communities are reminders that, coastal communities are not resilient to normally recurring hazards. This fact has raised the question of developing community resilience since the most effective approach to reducing the long-term impact of coastal hazards would be to enhance capacities of coastal communities through initiatives which are aimed at ensuring a sustainable recovery in the aftermath of a disaster as well as reducing people’s vulnerability to these disasters. Eight elements of resilience i.e., Governance, Coastal Resource Management, Land Use and Structural Design, Society and Economy, Risk Knowledge, Warning and Evacuation, Emergency Response and Disaster Recovery have been identified which are considered essential to reduce risk from coastal hazards, accelerate recovery from disaster events, and adapt to changing conditions by the affected community. In this paper, all the eight resilience elements have been examined with respect to vulnerability and capacity assessment in selected Tsunami (2004) affected districts in the state of Tamil Nadu, India in order to identify the extent of resilience.     

Heavy metal contamination in the sediment and plants of the Sundarbans,India

Heavy metals are one of the hazardous contaminants in the total environment. The present study shows that the Sundarbans soil is contaminated with sludge and moderately contaminated with Cd and Co according to Contamination factor (CF), Enrichment factor (EF), Index of geo-accumulation (Igeo), and Ecological risk factor (ERF). The correlation, principle component analysis and factor analysis showed that Mn and Fe might have lithogenic origin whereas Cu, Pb, Co and Cd have anthropogenic inputs. The screening quick reference table (SQuiRT) shows that Cu and Cd may exert a possible toxic effect on the sediment dwelling biota. The phytoremediation study revealed that the endangered Heritiera fomes leaves can accumulate 80% of cadmium from the soil, which is highest based on this study as compared to other mangroves. The study also indicated that threatened date palm Phoenix paludosa leaves can accumulate 74% and 73% of Cu and Fe, respectively, from the soil. Now a day, there has been a spurt in mangrove plantations worldwide for the conservation of mangrove ecosystem using ecological engineering approaches. The present study is very much useful to choose a proper plant to decontaminate the soil from various heavy metal pollutants for effective management of mangrove wetlands.     

Kinetic measurements of metal accumulation in two marine macroalgae

 We measured the uptake kinetics of four metals (Cd, Cr, Se and Zn) in two marine macroalgae (the green alga Ulva lactuca and the red alga Gracilaria blodgettii). Metal uptake generally displayed a linear pattern with increasing exposure time. With the exception of Cr, which exhibited comparable uptake rate constants at different concentrations, uptake rate constants of Cd, Se and Zn decreased with increasing metal concentration, indicating that the seaweeds had a higher relative uptake at lower metal concentration. Uptake of Cd and Zn was higher in U. lactuca than in G. blodgettii, whereas uptake of Cr and Se was comparable between the two species. Only Cd and Zn uptake in U. lactuca was significantly inhibited by dark exposure. A decrease in salinity from 28 to 10‰ enhanced the uptake of Cd, Cr, Se and Zn in U. lactuca 1.9-, 3.0-, 3.6-, and 1.9-fold, respectively. In G. blodgettii, Cd uptake increased twofold when salinity was decreased from 28 to 10‰, whereas uptake of Cr and Zn was not significantly affected by salinity change. The calculated depuration rate constants of metals in U. lactuca were 0.01 d⁻¹ for Cd, 0.05 to 0.08 d⁻¹ for Cr, 0.14 to 0.16 d⁻¹ for Se, and 0.12 to 0.15 d⁻¹ for Zn, and were relatively independent of the metal body burden in the algae. The predicted bioconcentration factor was 3 × 10⁴ for Cd, 2 × 10³ for Cr, 40 to 150 for Se, and 1 to 2 × 10⁴ for Zn in U. lactuca. Our kinetic study suggested that U. lactuca would be a good biomonitor of Cr and Zn contamination in coastal waters. Received: 14 September 1998 / Accepted: 29 May 1999     

Heavy metal selection of phosphoglucose isomerase allozymes in marine gastropods

The effects of zinc and copper pollution on the allozymic variation of phosphoglucose isomerase (Pgi) genotypes were tested in the Mediterranean marine gastropods Monodonta turbinata and M. turbiformis in 26 laboratory tests involving 2 081 adult individuals, with 545 survivors. Our results indicate differential survivorship of electrophoretical Pgi allozyme genotypes for both pollutants. Zinc pollution selected against the allozyme genotype SS in M. turbinata, whereas no differential survivorship was observed in M. turbiformis which lacks this allozyme. Copper pollution selected against the MM genotype in both species. These results are inconsistent with the neutral theory of allozyme polymorphisms and appear to reflect the adaptive nature of some Pgi genotypes in these marine gastropods.     

Integrated approach of assessing sedimentary characteristics of onshore sand deposits on the Velankanni coast, Tamil Nadu, India: sheds light on extreme wave event signatures

The refraction of the 2004 Indian Ocean tsunami waves caused drastic devastation along East coast of India, mainly in the area of investigation. Here, we appraise and integrate the sedimentary characteristics and microfossil studies of the area. The gigantic tsunami waves caused the landward fining of sediments that were carried as suspended load. Tsunami sediments have distinctive characteristics, like fine-to-medium grained sand, moderately to poorly sorted sediments which indicating sudden winnowing followed by tranquil flood. Positively skewed grain size distribution indicating unidirectional transport, and mesokurtic to platykurtic character implying poorly sorted single source origin. The species of benthonic foraminifers and ostracods reside in marine environment indicating shallow water origin of sediments. The onshore deposits are vertically divided into three depositional units interpreted from Ground Penetrating Radar (GPR) signatures—Unit 1 is a relatively continuous parallel layer indicative of calm environment; Unit 2 has paleochannels and burial scarps, seen as oblique reflections that might be indicative of an intense erosional environment; Unit 3 is interpreted as 2004 tsunami layer, has three subunits. Each main units have been separated by Heavy Mineral Concentrated (HMC) layers, deposited by continuous wave action (~?20 cm) and by the tsunami (>?30 cm) activity, evidenced by low magnetic susceptibility values at the bottom compared to the top of the HMC layers. GPR has been effectively utilized in this paper as subsurface imaging tool for the interpretation and reconstruction of stratigraphy, and also helped to unearth the erosional and depositional environments.     

Lithological and hydrochemical controls on distribution and speciation of uranium in groundwaters of hard-rock granitic aquifers of Madurai District,Tamil Nadu (India)

Uranium is a radioactive element normally present in hexavalent form as U(VI) in solution and elevated levels in drinking water cause health hazards. Representative groundwater samples were collected from different litho-units in this region and were analyzed for total U and major and minor ions. Results indicate that the highest U concentration (113 µg l^?1) was found in granitic terrains of this region and about 10 % of the samples exceed the permissible limit for drinking water. Among different species of U in aqueous media, carbonate complexes [UO₂(CO₃) ₂ ^2? ] are found to be dominant. Groundwater with higher U has higher pCO₂ values, indicating weathering by bicarbonate ions resulting in preferential mobilization of U in groundwater. The major minerals uraninite and coffinite were found to be supersaturated and are likely to control the distribution of U in the study area. Nature of U in groundwater, the effects of lithology on hydrochemistry and factors controlling its distribution in hard rock aquifers of Madurai district are highlighted in this paper.     

Heavy metal accumulation in water, sediments and fishes of Nallihan Bird Paradise, Turkey

The accumulation of some heavy metals such as Pb, Cd, Cu and Ni was determined in water sediment and fish samples (Albumus escherichii, Cyprinus carpio and Silurus glanis) collected from Nallihan Bird Paradise (NBP) and its vicinity (Sariyar Dam). The results showed that these metals are found widespread throughout the study area, but metal concentrations in the water samples are below the detection limits (BDL). Pb, Cd, Cu and Ni contamination were determined in sediments and in fish tissues (muscle and liver) and it was seen that they were accumulated and biologically magnified in lish tissues. Metal concentration levels in sediment samples were higher than that of water and fish tissues. The highest amount of metal concentrations in sediment samples among seven stations were determined in Usakbuku (Pb: 0.49 ppm), Sakarya River (Cu: 1.12 ppm) and Sariyar (Ni: 0.77 ppm). Unlikely to the other stations, no metal residues were determined in the sediment samples ofAladag Creek Station.     

Heavy metal and nutrient contamination of marine sediments in Hong Kong

A monitoring programme was performed to use marine sediments as an indicator of marine contamination in Hong Kong. A total of 51 samples were collected from eight marine sites and analysed for pH, redox potential, salinity, total‐N, total‐P, total organic carbon, and total Cu, Zn Pb, Cr and Cd. Sites with high industrial or aquacultural activities contained high total organic carbon contents, total‐N and total‐P contents. Sediments from sites with high industrial activities also enriched with heavy metals. Metal speciation results indicate that Cu and Cr existed mainly in the organic fraction, Pb and Zn were distributed approximately equally in both the organic and residual fractions while Cd mainly occurred in the residual fraction. The Cu, Cr and Zn contents were highly correlated with total organic carbon contents. All samples were classified as non‐acid forming according to the net acid generation test and only samples from the industrial site released a high concentration of heavy metals under a complete oxidising condition. The present study reveals that organic and heavy metal pollution is serious in the marine sediments of Hong Kong, and industrial and aquacultural activities are probably the major sources of contamination.     

Heavy metal accumulation in algae and sediments of the Black Sea coast of Turkey

The paper reports heavy metal accumulation in algae collected at four stations and in sediments at three stations on the Black Sea coast of Turkey. The metals analysed are Cd, Co, Cr, Cu, Fe, Pb, Sb and Zn. The metal content of algae increased generally (with some exceptions) from 1991 till 1993 in ?ile and Sinop. In the sediments Sb in ?ile, As in Riva, Fe, Zn in Sinop are high. According to these findings the metal pollution increased in Turkish area of the Black Sea during the years investigated.     

Distribution of chlorophyll,carotenoids and phytoplankton in relation to certain environmental factors along the central west coast of India

Distribution of chlorophyll pigments, carotenoids and abundance of phytoplankton in relation to certain environmental factors of the nearshore waters off the central west coast of India (latitudes 15°30 to 18°30N) were studied monthly at 7 stations during 1970/1971. Changes in the hydrographical factors and the biological processes occurring in the region during different months appear to be influenced by the pattern of upwelling along the northern and southern parts of the west coast of India. The pigment concentration shows a marked decrease in October, but is followed by a slow but steady rise, which reaches its maximum in April/May. A slightly smaller maximum is noticed in December/January. The composition of various chlorophyll pigments and carotenoids indicated the physiological state of phytoplankton populations during different months in the region investigated. Abundance of specific phytoplanktonic elements, consisting mainly of diatoms, in space and time, characterises the waters of the central west coast of India, indicating a clear succession of species.     

Heavy metal speciation,leaching and toxicity status of a tropical rain-fed river Damodar,India

Speciations of metals were assessed in a tropical rain-fed river, flowing through the highly economically important part of the India. The pattern of distribution of heavy metals (Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn) were evaluated in water and sediment along with mineralogical characterization, changes with different water quality parameters and their respective health hazard to the local population along the Damodar River basin during pre-monsoon and post-monsoon seasons. The outcome of the speciation analysis using MINTEQ indicated that free metal ions, carbonate, chloride and sulfate ions were predominantly in anionic inorganic fractions, while in cationic inorganic fractions metal loads were negligible. Metals loads were higher in sediment phase than in the aqueous phase. The estimated values of I_geo in river sediment during both the seasons showed that most of the metals were found in the I_geo class 0–1 which represents unpolluted to moderately polluted sediment status. The result of partition coefficient indicated the strong retention capability of Cr, Pb, Co and Mn, while Cd, Zn, Cu and Ni have resilient mobility capacity. The mineralogical analysis of sediment samples indicated that in Damodar River, quartz, kaolinite and calcite minerals were dominantly present. The hazard index values of Cd, Co and Cr were >?1 in river water, which suggested potential health risk for the children. A combination of pragmatic, computational and statistical relationship between ionic species and fractions of metals represented a strong persuasion for identifying the alikeness among the different sites of the river.     

Levels of tin in core sediments along the Alexandria Coast, Egypt

Tin concentrations were determined in surface and core sediments from three hot spots along the Alexandria coast, namely: Abu-Qir Bay, Eastern Harbour, and Western Harbour. The mean concentrations in surface sediment were 2.434, 3.212, and 5.572 μg/g dry weight for Abu-Qir Bay, Eastern Harbour, and Western Harbour, respectively. A sharp decrease in tin level in core sediments with depth was observed in almost all locations except for core 4 in Abu-Qir Bay and core 17 in the Eastern Harbour, where the sub-sample at the 5 cm level recorded the highest tin concentrations.