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Indian coastal waters are subjected to considerable pressure from sewage and industrial wastes, which are responsible for
the contamination of the coastal sediments with consequent loss in biosphere. The present investigation attempts to study
the significance of coarse material (Sand fraction) in the distribution of metals in polluted marine sediments. The study
revealed that coarse Sand component contains a relatively significant proportion of the anthropogenic metals (Cd, Cu, Pb and
Zn) and therefore it cannot be neglected in metal pollution studies of coastal sediments. Further, the distribution of anthropogenic
metals in both Silt + Clay and Sand fraction follow the same suit indicating similar pollution sources. From the total sediment
type (Silt + Clay and Sand fraction) all anthropogenic metals had a noticeable amount (>50%) in the acid extractable (and
potentially bio-available) fraction. This article stresses the importance of coarse fraction in metal pollution studies in
Indian coastal system. 相似文献
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The concept of anthropogenic impact is extremely important to be considered while analysing the ecology of coast and shelf
zones. For centuries, these zones have been the epicentres for various human activities, including urbanisation, construction
of sea ports and harbours, development of natural reservoirs (including oil production and fishing), marine aquaculture, shipping,
recreation and many others. Many of the activities in progress on both sides of the shoreline provide 50% or more of the gross
State/UT (Union Tertiary) product for surrounding states. The data shows that land-based and atmospheric sources account for
about two-thirds of the total contamination found in the marine environment, constituting 44 and 33%, respectively. The greatest
anthropogenic pollution pressure undoubtedly falls on the shelf zones and coastal areas. To prove this theory, a total of
25 bottom sediment samples were collected within the depth zone of 5 fathoms from the South Andaman coastal fringe for sediment
geochemistry studies and foraminiferal analysis. The samples were further analysed for heavy metal pollutants like Co, Cu,
Mn, Pb and Zn. The study yielded 20 benthic foraminiferal species. Of these, five benthic species were living including Ammonia beccarii, Calcarine calcar, Elphidium crispum, Operculina complanata and Nonion deppresula. The presence of deformed specimens and the domination of Ammonia spp. are indications of a polluted environment. Sampled coral reefs had high abundances of Operculina spp. The highest counts of benthic microbiota were found in finer sediment. Species diversity is very limited along the coastal
fringe of South Andaman Island in comparison with fauna from the coast of India. This first report of benthic foraminifera
from South Andaman Island will allow us to assess future impacts of marine pollution because foraminiferal deformations are
positively correlated to the concentrations of heavy metals (Cr, Cu, Mn, Pb and Zn). 相似文献
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The Tungabhadra River is one of the sacred rivers in south India. Industrial and mining operations on its banks generate enormous amounts of effluent that have led to substantial metal and nutrient contamination of the aquatic system. In the present investigation an attempt has been made to assess variation in the physico-chemical characteristics and speciation of zinc in the water and sediment of the Tungabhadra River. Most of the metal ions in the collected samples were in high concentrations compared to the applicable standards. The Individual Contamination Factor (ICF) of Zn was found to be more at Site-B compared to sites A and C. Zinc-bearing particles were characterized by the different morphologies measuring from large colloidal to small particles which were associated with biological structures or may be present in amorphous nature which were observed by Transition electron microscopy (TEM) with X-EDS (Energy dispersive spectrometry). In conclusion, the level of Zn contamination in the Tungabhadra River is increasing at an alarming rate due to industrial activities. 相似文献
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Sreenivasulu Ganugapenta Jayaraju Nadimikeri Sundara Raja Reddy Balam Chinnapolla Lakshmanna Ballari Rajasekhar Madiga Nirmala K Lakshmi Prasad Tella 《国际泥沙研究》2018,33(3):294-302
Sediment from twelve stations was sampled from the Tupilipalem Coast, southeast coast of India, and the presence of a set of heavy metals was established including iron (Fe), manganese (Mn), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), zinc (Zn) and cadmium (Cd). The heavy metals were assessed by factor analysis, the results of which showed positive and/or negative correlations among Fe, Mn, Cr, Cu, Ni, Pb, Zn, and Cd. Factor analysis also indicated that heavy metals in the sediments of the study area have different natural and anthropogenic sources. Similarly, a sediment pollution assessment was done using the Geoaccumulation Index (Igeo), Enrichment Factor (EF), and Pollution Load Index (PLI). The Geoaccumulation Index indicated that the surface sediment of the Tupilipalem Coast was extremely contaminated with Fe, Mn, Cr, Cu, Ni, Pb, and Zn. The calculation of enrichment factors showed a significant enrichment with respect to Pb, Zn, and Cd and a moderate enrichment with Cr, Cu, and Ni. The falling trend of average contents’ enrichment factors is Cd> Pb> Zn> Cu> Cr> Ni> Mn> Fe. The PLI values of the Cd show higher (>1) values due to the influence of distinct external sources like agricultural runoff, industrial activities, and other anthropogenic inputs. Ninety two percent of heavy metals under study showed the highest concentrations at station TP-5 where the Buckingham Canal and other agricultural and aquacultural effluents connect with the Bay of Bengal. This location is the second inlet which is periodically closed and it seemed that these parts of the study area are heavily affected by anthropogenic pollution. 相似文献
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