Seasonal Composition and Diversity of Zooplankton in Pichavaram Mangrove Forest, Southeast Coast of India

In the present study, the zooplankton diversity and distribution was studied in relation to seasonal variation of environmental parameters in the Pichavaram mangrove forest. Samples were seasonally collected (i.e., post-monsoon: January-2018 and monsoon: December-2018) from seven stations. A total of 48 zooplankton species belonging to two groups macro-zooplankton and micro-zooplankton were recorded during this study. A total of 48 species of zooplankton belonging to different groups were identified. Copepod was found to be the most dominant group and it contributed more than 50% of the total zooplankton collected in this study. The maximum number of zooplankton species (35) and diversity value (H’) 3.867 was recorded in the stations near coastal zone (P-7) during summer and minimum species number (24) and maximum species richness (d) 7.652 was recorded in stations near to freshwater zone (P-2) during monsoon. The species evenness (J') 0.866 was also recorded maximum at stations near river mouth (P-7). BIO-ENV (Biota-Environmental matching) and CCA results confirmed that the environmental parameters such as Temperature, Salinity, Dissolved Oxygen, Silicate, Chlorophyll, Primary Productivity, Total Biomass and Phaeopigments as the most influencing environmental parameters, which regulates zooplankton assemblage. The results of present study help to develop an understanding on the zooplankton distribution in mangrove forests, which will form a reliable tool in bio-monitoring studies</jats:p

Multivariate approach to determine the ecological preferences of phytoplankton in Uppanar estuary, southeast coast of India

In the present study, the phytoplankton diversity and distribution was studied in relation seasonal variation of environmental parameters in the Uppanar estuary. Samples were seasonally collected (i.e., pre-monsoon: July-2018 and summer: June-2019) from six stations. A total of 62 phytoplankton species belonging to three classes, 20 orders, 26 families and 36 genera were and among the three phytoplankton taxa, diatoms topped the list with 41 species followed by Dinoflagellates (17 species) and blue green algae (4 species). The maximum number of phytoplankton species (36) and diversity value (H’) 3.976 was recorded in the stations near river mouth (UE-6) during summer and minimum species number (21) and maximum species richness (d) 6.923 was recorded in stations close to industrialr zone (UE-1) during monsoon. The maximum species evenness (J') 0.928 was recorded at stations near river mouth (UE-6). BIO-ENV (Biota-Environmental matching) and CCA results confirmed that the environmental parameters such as Dissolved oxygen, Turbidity, Salinity, Water pH, Chlorophyll, Silicate, TN and TP as best match (ρω = 0.968) in determining phytoplankton distributions. The results of present study helps to develop an understanding on the phytoplankton distribution based on physico-chemical parameters, which will form a reliable tool in bio-monitoring studies.</jats:p