Microenvironments and anomalous benthic foraminiferal distribution within the neritic regime of the Dabhol-Vengurla sector (Arabian Sea)

Abstract

An anomalous distribution of benthic Foraminifera within the neritic regime at a few stations indicates the existence of microenvironments. The vertical distribution is marked by the restricted occurrence of @iCibicides@@ group at only one station (15) at 51 m and Miliolid group in station 18 at 25 m depth. The lateral distribution is characterised by a low total species number (TSN) but high total foraminiferal number (TFN) wherein at stations 6, 1, 12 and 26 @iTrochammina inflata@@; @iT. inflata@@ and @iT. pacifica@@ and @iAmmonia beccarii@@ and @iAmmobaculites agglutinans@@ are predominantly monospecific while other associated species are impoverished. The microisolation of these species is accounted to edaphic condition (for @iCibicides@@ group) at sta. 15, of organic matter percentages in the sediment (for Miliolid group) at sta. 18, @iTrochammina inflata@@ (at sta. 6); @iT. inflata@@, and @iT. pacifica@@ group (at sta. 1); @iAmmonia beccarii@@ (at sta. 12); @iT. pacifica@@ and @iAmmobaculites agglutinans@@ (at sta. 26) are characterised by low salinity (31.1 to 32.1 ppt) and estuarine condition and high organic matter content in the sediment