Mazharul Islam Sajeeb

Abundance of phytoplankton in the Halda river was studied during monsoon (July) & post monsoon (February). Samples were collected from three sampling stations- Station 01 (Moduna Ghat), Station 02 (Sattar Ghat), Station 03 (Najirbat). Total 20 species were identified. The highest number were recorded for Coscinodiscus Sp (600 cells/ liter) during post monsoon at station 03.

The average number of phytoplankton in station 01, station 02 and station 03 were found 2985 cells/liter, 3470 cells/liter,3870 cells/liter. The most abundance of phytoplankton was found in post monsoon.

The physio chemical parameter varied from as, temperature 27°to 29° during monsoon , 25°to 28° during post monsoon, PH 5.5 to 6 during monsoon and 5.5 to 5.9 during post monsoon, dissolve oxygen 4.285 mg/l to 5mg/l during monsoon, 4.285mg/l to 5.71 mg/l during post monsoon and transparency 26.5 to 32 cm during monsoon, 27 to 31 cm during post monsoon. The Shannon diversity index was ranged between 2.345 to 2.6 during monsoon and 2.59 to 2.62 during post monsoon. The richness of study areas ranges between 2 to 2.3 during monsoon and 1.99 to 2.28 during post monsoon. The evenness was found in range of 0.81 to 0.92 during monsoon and 0.87 to 0.92 during post monsoon.

Keywords: Phytoplankton, Monsoon, Post Monsoon, Biotic, pH Dissolved Oxygen, Biodiversity Index

View PDF