Author(s): M Mehedi Iqbal, M Shafiqul Islam and Md. Nurul Haider

Abstract: This study was carried out in the Rezukhal Estuary, Ukhia, Cox’s Bazar of Bangladesh from January 2013 to November 2013 at three different stations and sampling were done in the winter (January 2013), pre-monsoon (April 2013), and post-monsoon (November 2013). The abundance of zooplankton varied between 39.85 and 48.85 ind. m-3 during winter, 25.38 and 29.30 ind. m-3 during pre-monsoon and 33.31 and 38.38 ind. m-3 during post monsoon in the three stations. Copepods comprised the bulk of total zooplankton fauna in all three seasons; the highest 65.77% recorded at the station 3 during winter and the lowest 34.09% at the station 1 during pre-monsoon. The Shannon-Weiner Diversity Index (H') varied between 1.387 and 2.035, Evenness Index (J) between 0.5408 and 0.8981 and Species Richness (d) between 1.743 and 2.047 during the study period. Spearman rank correlation (BIO-ENV, PRIMER V.6) showed that water pH is the most important influencing factor having the highest correlation (r=0.856) with the zooplankton community. Total dissolved solid, water phosphate-phosphorus (PO4-P) and dissolved oxygen were identified as the best environmental variables and they influenced the zooplankton assemblage at different range of rank correlations (r=0.775 to 0.823). Salinity and total dissolved solid (TDS) negatively influenced the abundance of the most dominant zooplankton group, Copepods, at a 5% and 1% level of significance respectively. Chaetognatha, fish larva and Molluscs larva was positively influenced by water pH at a 1% level of significance while crab zoea by water temperature at a 5% level of significance.

Pages: 275-282  |  1474 Views  137 Downloads

Download Full Article: Click Here