Deep-Sea Benthic Foraminiferal Distribution in South West Indian Ocean: Implications to Paleoecology

Nadimikeri Jayaraju, Balam Chinnapolla Sundara Raja Reddy, Kambham Reddeppa Reddy, Addula Nallappa Reddy

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DOI: 10.4236/ijg.2010.12011                

Abstract

Five grab samples from the southwestern part of the Indian ocean were collected by ORV Sagar Kanya during the third expedition to the southern Indian ocean in June 2009. The sediment samples have been analyzed and recorded 36 benthic foraminiferal species belonging to 21 genera and 3 suborders. All the species were taxonomically identified, SEM photographed and illustrated. Deep sea-benthic foraminiferal species at different locations of South of West India Ocean (3150-4125 m water depth) is examined in terms of number of species (n) and diversity (d). The observed depth ranges of benthic foraminifera have been documented to recognize their bathymetric distribution. The valves of these parameters reached their maximum at 3190 m water depth. Productivity continued in the Indo-Pacific Ocean (the biogenic boom) and the Oxygen minimum zone (OMZ) intensified over large parts of Indian Ocean continually. The diversity values show more abrupt trend as depth increases. Species like Epistominella exigua and Pullenia bulloides occur at both 3150 m & 3465 m depths indicating depth persistence. Further, Oridorsalis umbonatus and Melonis sphaeroides occur at both 3150 m & 3465 m depths. Species like Gyroidina sp an indicate of low oxygen environment and Uvigerina hispida-costata indicative of high organic carbon are found to occur at 3150 m & 3740 m respectively. Factor analysis and Pearson correlation matrix was performed on foraminiferal census data of 10 highest ranked species which are present in at least one sample. 3 factors were obtained accounting for 72.81% of the total variance. Thus the study suggests that fluctuations in species diversity at the locations of the present study were related to changes in productivity during the geological past. Further, the faunal data do indicate the early Holocene Indian Ocean was influenced by increased ventilation perhaps by North Atlantic deep water and or circumpolar deep waters.

Keywords

Paleoecology, Benthicforaminifera, Holocene, Indian Ocean

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	D. Kroon, T. N. F. Steens and S. R. Froelstra, “Onset of Monsoonal Related Upwelling in the Western Arabian Sea as Revealed by Plantonic Foraminifera,” In: W. L. Prell, N. Niitsuma, et al., Eds., Proceedings of the Ocean Drilling Program, Scientific Results, College Station, Texas, Vol. 117, 1991, pp. 257-264.
[2]	A. K. Gupta, D. M. Anderson and T. J. Overpeck, “Ab-rupt Changes in the Asian South West Monsoon during the Holocene and their Links to the North Atlantic Ocean,” Nature, Vol. 421, No. 6921, 2003, pp. 354-356.
[3]	A. K. Gupta and E. Thomas, “Latest Miocene through Pleistocene Paleoceanography, Evolution of the NW In-dian Ocean (DSDP Site 21); Global and Regional Factors,” Paleooceanography, Vol. 14, No. 1, 1999, pp. 111-124.
[4]	B. H. Corliss, “Recent Deep-Sea Benthic Foraminiferal Distribution in the South Eastern Indian Ocean: Inferred Bottom Water Recites and Ecological Implications,” Ma-rine Geology, Vol. 31, No. 1-2, 1979, pp. 115-138.
[5]	A. J. Gooday, “Ephifaunal and Shallow Infaunal Forami-niferal Communities at Three Abyssal NE Atlantic Sites Subject to Differing Phytodetritus Input Regimes,” Deep-Sea Research, Vol. 43, No. 9, 1996, pp. 1395-1421.
[6]	J. Zachos, M. Pagni, L. Sloan, E. Thomas and K. Bilheps, “Trends, Rhythms and Abbreviations in Global Climate 65 Ma to Present,” Science, Vol. 292, No. 5517, 2001, pp. 686-693.
[7]	G. H. Hang and R. Tidemanm, “Effect of the Formation of the Isthmus of Panama on Atlantic Ocean Therohaline Circulation,” Nature, Vol. 393, No. 6686, 1998, pp. 673-676.
[8]	A. K. Gupta, R. K. Singh, S. Joseph and E. Thomas, “In-dian Ocean High Productivity Event (10-8 Ma): Linked to a Global Cooling or to the Incitation of the Indian Monsoons?” Geology, Vol. 32, No. 9, 2004, pp. 753-756.
[9]	C. S. Hernoylion and R. M. Owen, “Late Miocene-Early Pliocene Biogenic Bloom: Evidence from Low-Produc- tivity Regions of the Indian and Atlantic Oceans,” Pa-leogeography, Vol. 16, No. 1, 2001, pp. 95-100.
[10]	E. Thomas and A. J. Gooday, “Cenozoic Deep-Sea Ben-thic Foraminifers: Tracers for Changes in Oceanic Prod-uctivity,” Geology, Vol. 24, No. 4, 1996, pp. 355-358.
[11]	A. K. Gupta, M. Sundar Raj, K. Mohan and D. Soma, “A Major Change in Monsoon – Driven Productivity in the Tropical Indian Ocean during Ca 1.2-0.9 Mys: Fora- mi-niferal Faunal and Stable Isotope Data,” Paleogeo- graphy, Paleoclimatology, Paleoecology, Vol. 261, No. 3-4, 2008, pp. 234-245.
[12]	C. W. Smart, E. Thomas and A. T. S. Ramsay, “Mid-dle-Late Miocene Benthic Foraminifera in a Western Equatorial Indian Ocean Depth Transect: Paleooceno-graphic Implications,” Paleogeography, Paleoclimatology, Paleoecology, Vol. 247, No. 3-4, 2007, pp. 402-420.
[13]	F. J. Jorissen, H. C. Destigter and J. Widemark, “A Con-ceptual Model Explaining Benthic Foraminiferal Micro-habitats,” Marine Micropaleontology, Vol. 26, No. 1, 1995, pp. 3-15.
[14]	G. Schmiedl and A. Mackensen, “Multi Species Stable Isotopes of Benthic Foraminifers Revels Past Changes of Organic Matter Decomposition and Deep Water Oxy- genation in the Arabian Sea,” Paleooceangraphy, Vol. 21. 2006, p. 11.
[15]	A. R. Loeblich and H. Tappan, “Foraminiferal Genera and their Classification,” Van Nostrand Rinhold Camp, New York, 1987.
[16]	T. G. Gibson and W. M. Walker, “Floatation Methods for Obtaining the Foraminifera from Sediment Samples,” Jour au Paléo, Vol. 41. No. 5. 1967, pp. 1294-1297.
[17]	N. Jayaraju, B. C. Sudara Raja Reddy and K. R. Reddy, “Anthropogenic Impact on Andaman Coast Monitoring with Benthic Foraminifera, Andaman Sea, India,” Envi-ronmental Earth Science, Vol. 183, 2010, pp. 1049-1052.
[18]	R. K. Singh, and A. K. Gupta, “Systematic Decline in Benthic Foraminiferal Species Diversity Linked to Prod-uctivity Increases over the Last 26 MA in the Indian Ocean,” Journal of Foraminiferal Research, Vol. 35, No. 3, 2005, pp. 219-229.
[19]	K. R. Ajay and M. S. Srinivasan, “Pleistocene Oceano-graphic Changes Indicated by Deep-Sea Benthic Forami-nifera in the Northern Indian Ocean,” Proceedings of In-dian Academic Sciences, Vol. 103, No. 4, 1995, pp. 499-517.
[20]	G. Schmiedl and D. C. Lenschrer, “Oxygenation Changes in the Deep Western Arabian Sea during the Last 190,000 Years: Productivity versus Deep-Water Circulation,” Pa-leoocenography, Vol. 20, No. 2, 2005, pp. 1-14.
[21]	N. T. Jannik, W. J. Zachariasse and G. J. Van Deer Zwaan, “Living (Rose Bengal Stained) Benthic Foraminifera from the Pakistan Continental Margin (Northern Arabian Sea),” Deep-Sea Research, Vol. 45, No. 9, 1998, pp. 1483-1513.
[22]	B. H. Corliss, “Recent Deep-Sea Benthic Foraminiferal Distribution in the South Eastern Indian Ocean: Inferred Bottom Water Recites and Ecological Implications,” Ma-rine Geology, Vol. 31, No. 1-2, 1979, pp. 115-138.
[23]	S. S. Streeter and N. J. Shackleton, “Paleocirculation of the Deep North Atlantic: 150,000 Year Record of Benthic Foraminifera and Oxygen-18,” Science, Vol. 203, No. 4376, 1979, pp. 168-171.
[24]	T. Uchio, “Biological Results of the Japanese Antarctic Expedition, Benthonic Foraminifera of the Antarctic Ocean,” Special Publication, Walkayama, Vol. 12, 1960, pp. 21.
[25]	A. Mackensen, G. Schimiedl, J. Harlogg and M. Giese, “Deep-Sea Foraminifera in the South Atlantic Ocean: Ecology and Assemblage Generation,” Micropaleontology, Vol. 41, No. 4, 1995, pp. 342-358.
[26]	R. K. Singh and A. K. Gupta, “Systematic Decline in Benthic Foraminiferal Species Diversity Linked to Prod-uctivity Increases over the Last 26 MA in the Indian Ocean,” Journal of Foraminiferal Research, Vol. 35, No. 3, 2005, pp. 219-229.
[27]	Q. Miao and R. C. Thunell, “Recent Deep-Sea Benthic Foraminiferal Distribution in the South China and Sulu Seas,” Marine Micropaleontology, Vol. 22, 1993, pp. 1-32.
[28]	A. K. Gupta, “Taxonomy and Bathymetric Distribution of Holocene Deep-Sea Benthic Foraminifera in the Indian Ocean and Red Sea,” Micropaleontology, Vol. 40, No. 4, 1994, pp. 351-367.
[29]	M. Den Dulk, G. J. Reichart, S. Van Heyst, W. J. Zacha-riasse and G. J. Vander Zewaan, “Benthic Foraminifera as Proxies of Organic Mater Flux and Bottom Water Oxygenation? A Case History from the Northern Arabian Sea,” Paleogeography, Paleoclimatology, Paleoecology, Vol. 161, No. 3, 2000, pp. 337-359.
[30]	J. O. R. Hermelin and G. B. Shimmield, “The Importance of the Oxygen Minimum Zone and Sediment Geochemi-stry on the Distribution of Recent Benthic Foraminiferal from the Northwestern Indian Ocean,” Marine Geology, Vol. 91, No. 1-2, 1990, pp. 1-29.
[31]	A. K. Gupta, S. Joseph and E. Thomas, “Species Diversity of Miocene Deep-Sea Benthic Foraminifera and Waters mass Stratification in the North Eastern Indian Ocean,” Micropaleontology, Vol. 47, No. 2, 2001, pp. 111-124.
[32]	E. Thomas and A. J. Gooday, “Cenozoic Deep-Sea Ben-thic Foraminifers: Tracers for Changes in Oceanic Prod-uctivity?” Geology, Vol. 24, No. 4, 1996, pp. 355-358.