Executive Summary : | The proposed study is aimed to evaluate the urban pollution in the marginal marine sediments of Chennai city on the basis of the study of trace metal concentration in sediments (heavy metals pollution) and its impact on the benthic foraminifera tests and its shell chemistry. For this investigation the most sensitive unicellular organism, foraminifera will be used as a bio-indicator. This project is aimed to assess the urban pollution in the sediments of marginal marine systems and distinguish the influences of pollutants and environmental parameters (e.g., salinity, temperature, depth and pH) on the foraminiferal distribution and test morphology. The mineralized shells of foraminifera preserve a record of the ocean and marginal marine chemical and physical properties that can be utilized for evolutionary, paleobiological, and geochemical analyses of global environmental and climatic changes (P.G. Mortyn,et.al., 2007, Fabrizio Frontalini,et.al., 2009). Analysis of the rainfall in the megacities in India during the last 50 years shows that there is no significant trend in the annual rainfall, but the seasonality and intensity are changing. Increasing seasonality creates changing pattern in sediment supply into the marginal marine systems, increasing pollutant accumulation in the sediment stratum. To address these problems in the marginal marine microenvironments in Urban Chennai, three locations are identified on basis of the pollutant discharge into the water bodies and density of anthropogenic activities. Sediment samples will be collected in surface and subsurface stratum in these localities and sedimentology, trace element chemistry of the sediments and shell chemistry of the dominant foraminifera tests will be carried out. The seasonal studies will yield the results of the present environmental condition of the marginal system and subsurface sediment results will provide the past environmental nature of the study area. Shell chemistry of the dominant species will yield the geochemical evolution in the sediment stratum and also reveal the climatic variation. The evolution of metal enrichment into the sediment stratum due to urban pollution and its impact on the microfauna will be addressed. References: P. G. Mortyn and M.A. Martínez-Botí, ‘Planktonic foraminifera and their proxies for the reconstruction of surface-ocean climate parameters’ Contributions To Science, 3 (3): 371–383 (2007) Institut d’Estudis Catalans, Barcelona DOI: 10.2436/20.7010.01.14 ISSN: 1575-6343 Fabrizio Frontalini, Carla Buosi , Stefania DaPelob, Rodolfo Coccionia, Antonietta Cherchib, Carla Bucci, 'Benthic foraminifera as bio-indicators of trace element pollution in the heavily contaminated Santa Gilla lagoon (Cagliari, Italy)', Marine Pollution Bulletin, Volume 58, Issue 6, June 2009, Pages 858-877 |