Zooplankton community distribution along offshore transects of some Indian estuaries of east coast: A taxonomic investigation during a summer cruise

Abstract

1781-1791<span style="font-size:9.0pt;line-height: 115%;font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" mso-bidi-font-family:"times="" roman";mso-ansi-language:en-us;mso-fareast-language:="" en-us;mso-bidi-language:ar-sa"="" lang="EN-US">Zooplankton abundance and composition were studied by selecting offshore transects of seven estuaries <i style="mso-bidi-font-style: normal">viz. Pennar, Krishna, Godavari, Gosthani, Rushikulya, Devi and Mahanadi along east coast of India during April, 2011. During the study period, sea surface temperature (SST) varied from 27.9°C to 28.3°C with an average of 28.1°C. Salinity varied from 33.0 to 35.0 PSU with an average of 34.5 PSU.  Different zooplankton groups belonging to 13 phyla were recorded from seven transects. Copepods dominated the community with 50.5 to 96.8%. Calanoids, namely Paracalanus parvus, P. aculeatus, Temora turbinata were common in all the transects studied. <span style="font-size:9.0pt;line-height:115%; font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" mso-bidi-font-family:"times="" roman";mso-ansi-language:en-gb;mso-fareast-language:="" en-us;mso-bidi-language:ar-sa;mso-bidi-font-weight:bold"="" lang="EN-GB">The Shannon’s diversity index (H´) was found highest in Pennar (2.666) and lowest in Godavari transect (1.785). From cluster analysis and non-parametric multidimensional scaling (nMDS), it is observed that the species composition was changing from north to south of the study area. </span