Response of sedimentary nucleic acids to benthic disturbance in the Central Indian Basin

Abstract

Information on the response of nucleic acids (i.e., DNA and RNA) to simulated benthic disturbance was obtained from samples collected from eight sediment cores (0-10 cm) located in the Central Indian Basin (CIB). In general the total sedimentary DNA (DNA) increased with depth (from 380.09 to 408.99 mu g g sup(-1)), while total sedimentary RNA (RNA) decreased (from 878.13 to 484.16 mu g g sup(-1)). Following the simulated benthic disturbance brought about by the benthic hydraulic disturber, DNA decreased by 10% along the disturbed track while the RNA increased by around 75%. The RNA=DNA ratio decreased nearly 10%. However, the ratio doubled along the disturbed track suggesting that the activity was stimulated at molecular level following artificial disturbance. The nucleic acid ratio thus shows that the CIB sediments are metabolically active, and with disturbance the activity tends to increase further.