Agricultural Research Management Information System

Home
Research Summary
Search
About Us
- ARMIS
- Brochure
Contact Us
Report
User Request
Data Input
Help
- Operation Manual
  - PDF
  - Video
- Program Area & Commodity
We have reached 37600 number of research entries at this moment.

- Logout

Research Detail

Home
Research
Detail

Diversity, Distribution and Density of Estuarine Phytoplankton in the Sundarban Mangrove Forests, Bangladesh

ABDUL AZIZ
Department of Botany, University of Dhaka, Dhaka

MASHRURA RAHMAN
Department of Botany, University of Dhaka, Dhaka

ASHFAQUE AHMED
Department of Botany, University of Dhaka, Dhaka

Abstract/ Executive Summary:

Diversity, distribution and density of estuarine phytoplankton from nine sites under four Ranges of the Sundarban Mangrove Forests (SMF), Bangladesh have been studied. The phytoplankton communities represented by 36 species which belonged to Chlorophyceae (3), Euglenophyceae (2), Bacillariophyceae (30) and Xanthophyceae (1). Occurrence of taxa and their densities were highest near the confluence of Hangsha River (R) with the river Murdat at Patcosta. Shannon-Wiener diversity index was also highest (H = 3.494) in this area. Lowest density of phytoplankton and diversity indices (H = 1.661) were found in Bal R., Bisandri Khal and Kalabogi R. Oocystis pusilla, Coscinodiscus excentricus, C. lineatus and Navicula brekkeansis occurred abundantly, while Cyclotella comta, Thalassionema nitzschioides and Lioloma delicatula were common. Coscinodiscus lineatus was distributed in all the nine sites including high and low tides indicating its high capacity to tolerate habitat fluctuations. Chaetoceros socialis was found only in Passur R. with low salinity, conductivity and total dissolved solids. The total numbers of phytoplankton individuals per liter were generally higher during low tide than those of high one. Principal Component Analysis (PCA) showed the relationship between pH and some species of phytoplankton.

Keywords: Phytoplankton, Mangrove, Estuarine algae, Centrales, Pennales

Location:

Start Date:

End Date:

Program Area: Resource Development and Management

Commodity:

Objectives:

The present research was undertaken to study the diversity, distribution and the density of phytoplankton in relation to the water chemistry in the estuary of different ranges of the SMF.

Methodology:

A total of 65 phytoplankton samples from nine sites (five samples from each site and at some sites samples from high and low tide conditions) were collected between 25 and 29 March, 2010 covering four Ranges of the SMF. Details of the study sites have been provided in Aziz et al. (2011). For each sample, 22 liter water was passed through plankton net of 40 μm mesh aperture and the concentrates were preserved in 4% formalin. pH (HANNA HI 98127), conductivity (Aqualitic CD 22), salinity (Hand Refractometer, VEEGEE STX-3), and TDS (HANNA HI 9034) of water were determined in the field immediately with the help of respective instruments. Alkalinity was determined following Wetzel and Likens (1979) Identification of phytoplankton taxa were made following Cupp (1943), Subrahmanyan (1946), Islam and Begum (1970), Islam and Aziz (1975, 1977, 1979), Germain (1981), Aziz and Ara (2000), Aziz and Tanbir (2003), Islam and Akhter (2004) and Ahmed et al. (2008, 2009). Shannon-Wiener Diversity indices were calculated following Ruggiero and Marchant (1979). Principal Component Analysis (PCA) was done using MINITAB 14 program.

Source of Information: Bangladesh J. Bot. 41(1): 87-95, 2012 (June)

Article Link (Online Journal):

Funding Source:

Total Budget (Tk.) :

Achievement/Findings:

Based on the highest number of individuals per liter found in the samples, the following phytoplankton were selected for Principal Component Analysis (PCA), e.g Coscinodiscus lineatus, C. excentricus, Lioloma delicatula, Cyclotella comta, Ocystis pusilla, Navicula brekkaensis and Thalassionema nitzschioides. The PCA analysis showed that all variables except pH have positive correlation with C. lineatus, C. excentricus, L. delicatula, Cyclotella comta, O. pusilla. On the other hand, these variables have negative correlation with N. brekkaensis and T. nitzschioides. These two diatom species have positive correlation with pH. Using PCA, Out of 36 species reported from SMF, a couple of centric and pinnate diatoms and Oocystis pusilla (a green alga) were dominant. Coscindiscus lineatus was distributed in all the nine sites including high and low tides, indicated its capacity to tolerate high fluctuations of water chemistry. This was followed by C. excentricus. Chaetoceros socialis was found only in Passur R. between Nalianala and Chandpai Ranges, a zone of low salinity, conductivity and total dissolved solids.

Knowledge Management: Journal