Changes in surface productivity and subsurface denitrification during the holocene: a multiproxy study from the eastern Arabian sea

• Main Authors: Agnihotri, Rajesh, Bhattacharya, S. K., Sarin, M. M., Somayajulu, B. L. K.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Sage Publications 2003
• Subjects: QE Geology; North Atlantic
• Online Access: http://repository.ias.ac.in/52747/; http://hol.sagepub.com/content/13/5/701.short

Spatial and temporal variations in the intensity of subsurface denitrification in the water-column of the eastem Arabian Sea have been investigated using chemical and isotopic proxies. The data show a steady increase in the denitrification intensity from ~10 ka to ~2 ka BP, probably caused by changes in surface productivity fuelled by strengthening of upwelling (monsoonal intensity). In addition, changes in redox conditions and detrital material input are assessed using abundances of a suite of major and trace elements. The temporal variations in some of the monsoonal proxies are characterized by periodicities of ~1400 and ~700 years, similar to those reported in the South Asian (Chinese) monsoon and high-latitude climate (north Atlantic region).