Macrobenthic community structure of coastal Arabian Sea during the Fall intermonsoon

Abstract

<span style="font-size:9.0pt;font-family: " times="" new="" roman","serif";mso-fareast-font-family:"times="" roman";mso-ansi-language:="" en-gb;mso-fareast-language:en-us;mso-bidi-language:hi"="" lang="EN-GB">In the Arabian Sea, organic matter produced during the upwelling period reaches the seafloor by the end of the monsoon and during the fall intermonsoon period (FIM). Studies on the benthic community is lacking during this period. Therefore, we predict that the FIM period is critical in structuring the coastal benthic community. Results indicated <i style="mso-bidi-font-style:normal">Coscinodiscus </i>sp. and <i style="mso-bidi-font-style:normal">Thalassiosira</i> sp. were dominant in the phytoplankton and the microphytobenthos community. Zooplankton was dominated by small sized calanoid copepods followed by larval forms of polychaete and fish. Macrofauna was dominated by the juveniles of interface feeding polychaete, <i style="mso-bidi-font-style:normal">Paraprionospio pinnata</i>. The quality of food from the surface flux supported the macrofaunal community and explained the successful recruitment of dominant <i style="mso-bidi-font-style:normal">P. pinnata</i>. Therefore, species composition and dominance of juveniles among the macrofaunal community suggest that macrobenthic recruitment coincides with the timing of organic matter flux so that the benthic community benefits from the sinking detritus.</span>