Distribution of living coccolithophores in eastern Indian Ocean during spring intermonsoon

Authors:
Open Access
Publisher website
Google Scholar
Abstract
We studied the biodiversity of autotrophic calcareous coccolithophore assemblages at 30 locations in the Eastern Equatorial Indian Ocean (EEIO) (80°–94°E, 6°N–5°S) and evaluated the importance of regional hydrology. We documented 26 species based on the identification of coccospheres and coccoliths, respectively. The coccolithophore community was dominated byGephyrocapsa oceanica,Emiliania huxleyi,Florisphaera profunda,Umbilicosphaera sibogae, andHelicosphaera carteri. The abundance of coccoliths and coccospheres ranged from 0.2 × 103to 160 × 103coccoliths l−1and 0.2 × 103to 68 × 103cells l−1, averaged 23 × 103coccoliths l−1and 9.4 × 103cells l−1, respectively. Biogenic PIC, POC, and rain ratio mean values were 0.50 μgC l−1, 1.047 μgC l−1, and 0.10 respectively. High abundances of both coccoliths and coccospheres in the surface ocean layer occurred on the north of the equator. Vertically, the great majority of coccoliths and coccospheres were concentrated in water taken from depths of <75 m. The ratios between the number of coccospheres and free coccoliths indicated that coccoliths experience different levels of dissolution when transported to deep water. Abundant coccolithophores mainly occurred at the west of 90°E, which is in accordance with the presence of Wyrtki jets. Patterns of coccolithosphores and of coccoliths have been reflected in hydrological processes.
Funding Information
  • National Natural Science Foundation of China (41676112, 41306119)
  • National Basic Research Program of China

This publication has 77 references indexed in Scilit: