@article {saravanan_reconstructing_2024,
	title = {Reconstructing hypoxia on the eastern Arabian sea continental shelf during the past \~{}7400 years: A multi-proxy approach},
	journal = {Quaternary International},
	year = {2024},
	abstract = {Shallow-sea environmental variations in the eastern Arabian Sea (EAS) have been related to monsoon variability, poorly ventilated intermediate water, and primary productivity changes. To understand these conditions, benthic foraminiferal assemblages, oxygen isotope ratios, and total organic carbon content have been examined in sediment Core SK291/GC13 from the EAS. We aim to retrieve decadal to centennial time-scale changes in past oxygenation and paleoproductivity during the last 7400 calibrated years before the present (cal yr BP). Our proxy data suggest that the oxic benthic foraminifera species were dominant during \~{}7400{\textendash}6000~cal~yr BP. The change from oxic to dysoxic occurred during ca. 6000{\textendash}3500~cal~yr BP, and transition from dysoxic to suboxic environmental conditions happened at ca. \~{}3500~cal~yr BP. These changes are contemporaneous with weakening of the Indian summer monsoon beginning at \~{}5500~cal~yr BP which culminated into a major arid phase so-called ca 4.2 ka event in the Indian subcontinent. The EAS experienced low productivity during the early phase of our studied interval (\~{}7400{\textendash}6000~cal~yr BP) and higher productivity in the middle Holocene (6000{\textendash}3000~cal~yr BP), as revealed by the total organic carbon and benthic assemblages. Furthermore, productivity increased in the warm period and decreased in the Little Ice Age on a decadal scale. The spectral analysis of total organic content and suboxic species indicates a 23-year Hale (solar) cycle during the last millennium, indicating a close relationship between solar activity and monsoon variability. The strengthening of the El Nino-Southern Oscillation perhaps amplified due to increased solar activity in the last millennium, which influenced the climate of the EAS. The study highlights paleo-oxygenation shifts based on benthic foraminiferal assemblages, which are crucial for understanding changes in the oxygen minimum zones (OMZs) and their potential impacts on marine ecosystems.},
	keywords = {Benthic assemblages, Goa coast, Hale cycle, Little ice age, Oxygen minimum zone, Suboxic environment},
	issn = {1040-6182},
	doi = {10.1016/j.quaint.2024.05.007},
	url = {https://www.sciencedirect.com/science/article/pii/S1040618224001630},
	author = {Saravanan, Ponnusamy and Gupta, Anil K. and Li, Xiangzhong and Zheng, Hongbo and Panigrahi, Mruganka K.}
}
@article { ISI:000268272100013,
	title = {Fish scales in sediments from off Callao, central Peru},
	journal = {DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY},
	volume = {56},
	number = {{16}},
	year = {2009},
	month = {JUL 15},
	pages = {1113-1124},
	type = {Article},
	abstract = {We study fish scales as a proxy of fish abundance and preservation biases together with phosphorus from fish remains (P(fish)) in a sediment core retrieved off Callao, Peru (12 degrees 1{\textquoteright}S, 77 degrees 42{\textquoteright}W; water depth = 179 m; core length = 52 cm). We interpret our results as a function of changing redox conditions based on ratios of redox-sensitive trace elements (Cu/Al, Mo/Al, Ni/Al, Zn/Al, V/Al), terrigenous indicators (Fe in clays, Ti, Al), and biogenic proxies (CaCO(3), biogenic opal, total nitrogen, organic carbon, barite Ba). The core covers roughly 700 years of deposition, based on (210)Pb activities extrapolated downcore and (14)C dating at selected intervals. Our fish-scale record is dominated by anchovy (Engraulis ringens) scales followed by hake (Merluccius gayii) scales. The core presented an abrupt lithological change at 17 cm (corresponding to the early 19th century). Above that depth, it was laminated and was more organic-rich (10-15\% organic carbon) than below, where the core was partly laminated and less organic-rich (< 10\%). The lithological shift coincides with abrupt changes in dry bulk density and in the contents of terrigenous and redox-sensitive trace elements, biogenic proxies, and fish scales. The remarkable increase in redox-sensitive trace elements in the upper 17 cm of the core suggests more reducing conditions when compared with deeper and older horizons, and is interpreted as an intensification of the oxygen minimum zone off Peru beginning in the early 19th century. Higher fish-scale contents and higher P(fish)/P(total) ratios were also observed within the upper 17 cm of the core. The behavior of biogenic proxies and redox-sensitive trace elements was similar; more reduced conditions corresponded to higher contents of CaCO(3), C(org), total nitrogen and fish scales, suggesting that these proxies might convey an important preservation signal. (C) 2008 Elsevier Ltd. All rights reserved.},
	keywords = {Callao, Clupeoid fish, Molybdenum, Oxygen minimum zone, Peru, Redox-sensitive trace elements},
	issn = {0967-0645},
	doi = {10.1016/j.dsr2.2008.09.015},
	author = {Diaz-Ochoa, J. A. and Lange, C. B. and Pantoja, S. and De lange, G. J. and Gutierrez, D. and Munoz, P. and Salamanca, M.}
}
@article {1842,
	title = {Late Quaternary benthic foraminifera from Ocean Drilling Program Hole 716A, Maldives Ridge, southeastern Arabian Sea},
	journal = {Micropaleontology},
	volume = {55},
	year = {2009},
	note = {424cdTimes Cited:5
Cited References Count:47
},
	month = {2009},
	pages = {23-48},
	abstract = {A study on deep-sea benthic foraminifera from the interval similar to 445 ka BP to the Present of the Ocean Drilling Program (ODP) Hole 716A (4 degrees 56.0{\textquoteright}N, 73 degrees 17.0{\textquoteright}E; preser t water depth 533.3m), Maldives Ridge. southeastern Arabian Sea, documented 201 species belonging to 105 genera. These taxa were examined under scanning electron microscope (SEM) to illustrate their interspecific morphological variations. Several of these species are dominant showing significant down core fluctuations in their abundances whereas some are rare and sporadic.},
	keywords = {benthonic foraminifera, equatorial indian-ocean, Holocene, late neogene, monsoon, Oxygen minimum zone, productivity, red-sea, south atlantic-ocean, Water masses},
	isbn = {0026-2803},
	author = {Sarkar, S. and De, S. and Gupta, A. K.}
}
