Anthropogenic impact on Andaman coast monitoring with benthic foraminifera, Andaman Sea, India

Abstract

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).

The distribution of benthic foraminiferal assemblages in the north-west coastal region of Malacca Straits, Malaysia

“…Hallock [32] explained that in normal marine salinities, abundant food source with intermittent hypoxia can create a favourable environment for Ammonia. Similar distribution of Ammonia was reported by Jayaraju et al in the Andaman Sea [35] . This suggests that Ammonia is a stress-tolerant taxon and could dominate highly stressed environments in the coastal waters of the Malacca Straits [34][35][36] .…”

“…Similar distribution of Ammonia was reported by Jayaraju et al in the Andaman Sea [35] . This suggests that Ammonia is a stress-tolerant taxon and could dominate highly stressed environments in the coastal waters of the Malacca Straits [34][35][36] . Likewise, this could explain why Elphidium was not highly abundant, as Elphidium spp.…”

“…This could explain why agglutinated genera were most abundant in Pantai Acheh, which was characterized by low salinity compared to other sampled sites. Therefore, it is possible that the distribution patterns of agglutinated foraminiferal assemblages in this study were influenced by sediment grain sizes and salinity [37,35,38] , similar to findings by Mohamed et al [39] which showed the significant influence of salinity and sediment grain-size on the distribution of agglutinated foraminiferal assemblages in the Sedili Besar River and its offshore area (SE Malaysia).…”

Anthropogenic Impact on Benthic Foraminifera, Abu-Qir Bay, Alexandria, Egypt

“…Significant percentages of abnormal tests in foraminiferal assemblages has been attributed to environmental stress caused by large fluctuations in, or extreme levels of environmental parameters such as salinity, DO, temperature, pH, sedimentation, pollution, and hydrodynamics (Geslin andothers, 1998, 2000;Bergin and others, 2006;Nigam and others, 2006;Jayaraju andothers, 2008, 2010;Coccioni and others, 2009). In Abu-Qir Bay, We attribute the highest percentages of foraminiferal test deformations that occur at sites S1-S3 to high pollution levels and, also at S1, to the turbulence associated with harbor activities.…”

Organic matter from benthic foraminifera (Ammonia beccarii) shells by FT-IR spectroscopy: A study on Tupilipalem, South east coast of India

“…The fossil foraminiferal studies help to assess the palaeo-depth, palaeosalinity and palaeo-environment and are useful in palaeogeographic reconstruction and ecological studies [3]. Foraminifera are valuable indicators of past environmental change [4]. Their sensitivity to pollutants may be expressed by modification in test form or assemblage composition [5], [6].…”