Textural characteristics and ecology of near shore benthic foraminifera from Kottaipattinam to Kodiyakarai, Palk Strait, Southeast Coast of India

Abstract

The present study aims to understand the distribution of benthic foraminifera in surface sediments collected from Kottaipattinam to Kodiyakarai, Palk Strait southeast coast of India. The analysis reveals the presence of 79 species belonging to 42 genera, 24 families, 12 super-families, 19 sub-families, 5 sub-orders and, 5 orders have been reported and illustrated. Out of the total population count of 11,719 specimens, 705 were observed to be Rose Bengal-stained, and are considered to be living at the time of sample collection. Environmental parameters such as water depth, pH, bottom water temperature, dissolved oxygen, salinity, CaCO3, organic matter, sand, silt, and clay contents were determined to adopt standard methodology. Ammonia beccarii (Linnaeus) is the most abundant counterpart in the study area; followed by Asterorotalia trispinosa (Thalmann) and Ammonia tepida (Cushman). Besides that, Spiroloculina corrugata, Spiroloculina angulata, Quinqueloculina bicostata, Quinqueloculina echinata, Pyrgo depressa, Pyrgo laevis, Pseudotriloculina rotunda, Parrina brady, Cancris oblonga, Elphidium hispidulum, Elphidium norvangi, these species were not previously observed in this study site. The textural analysis reveals that the sediments are chiefly composed of sand with less clay and silt. The organic matter content shows a high loading factor in the study site followed by CaCO3. Further, the statistical analysis shows organic matter is major controlling factors in the study site and benthic foraminiferal assemblages are definitely bound to be influenced by the high volume of freshwater influx in the study site.