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

Bacterial Load in Relation to Physicochemical Parameters and Phytoplankton Abundance of an Urban Pond

MD ABDUL KARIM
Department of Botany, University of Dhaka, Dhaka

ZN TAHMIDA BEGUM
Department of Botany, University of Dhaka, Dhaka

MD SARIFUL ISLAM
Department of Botany, University of Dhaka, Dhaka

Abstract/ Executive Summary:

Abundance of bacteria and phytoplankton was studied in different months of an urban pond of Dhaka Metropolis from May 2009 to February 2010. Interrelationships among bacteria, phytoplankton densities and the physiochemical properties were also determined. The abundance of bacteria ranged from 5.9×103 to 1.5 ×107 cfu/100 ml and showed high densities between May and July, while the density of phytoplankton varied from 6.7×104 to 7.5×106 cells/l. Bacterial abundance showed a significant positive correlation with air and water temperature, while phytoplankton showed a significant negative correlation with both of them. Furthermore, bacteria showed a significant positive correlation with conductivity, TDS and alkalinity. Among the physicochemical variables water temperature was significantly correlated with air temperature, pH and alkalinity. Conductivity correlated significantly with TDS and alkalinity. With few exceptions there was inverse relationship between phytoplankton and bacterial abundance in the pond.

Keywords: Bacteria, Physicochemical parameters, Phytoplankton, Pond

Location: Dhaka

Start Date: 01-05-2009

End Date: 20-02-2010

Program Area: Resource Development and Management

Commodity:

Objectives:

The present study was undertaken to investigate the relationships among bacteria and phytoplankton density together with other physicochemical parameters in a pond of Dhaka Metropolis.

Methodology:

The study was carried out from May, 2009 to February, 2010 in Jahurul Haque Hall pond of Dhaka University Campus, which is situated within 23°43′41″ to 23°43′45″N and 90°23′18″ to 90°23′23″E. The pond is perennial and more or less rectangular in shape. The area of the pond is about 1.05 ha having water depth 8 - 10 m with steep slopes. It has no out let or inlet and presently it is used for fish culture. Sampling was done in five different locations of the pond and the data were pooled to mean values for plotting. Air and water temperature were measured at the time of sampling by a mercury thermometer, while, pH, conductivity, TDS, alkalinity and DO were measured with the methodologies followed by Karim et al. (2010). Dilution plate and spread plate techniques were used for the enumeration and isolation of bacteria from the water sample in nutrient agar medium at pH 7.2. Inoculated plates were incubated at 37°C. After 24 hr of incubation, the plates having well discrete colonies grown on agar plates were selected for counting and the data were expressed as colony forming unit (cfu). Collection, preservation, qualitative and quantitative assessment of phytoplankton was done following the method of Sultana et al. (1999). During the investigation a total of 20 measurements were carried out for each parameter and the data were used for Pearson’s Correlation analysis to find the interrelationships among the variables.

Source of Information: Bangladesh J. Bot. 41(1): 15-20, 2012 (June)

Article Link (Online Journal):

Funding Source:

Total Budget (Tk.) :

Achievement/Findings:

The highest count of total phytoplankton was recorded in late February. This was due to the predominance of dinoflagellate group of phytoplankton from late November to late February i.e., in winter season. With a few exceptions the bacterial abundance was inversely related to the phytoplankton abundance. Observation of lower count of total phytoplankton in June was more or less similar to the results reported earlier in a pond at Bakerganj, Bangladesh. The matrix of product moment correlation among nine different variables. Bacteria (cfu) showed a significant positive correlation with air temperature, water temperature, conductivity, TDS and alkalinity. But, phytoplankton showed a significant negative correlation with air temperature and water temperature and a significant positive correlation with pH with few exceptions. Among the physicochemical variables water temperature was significantly correlated with air temperature, pH and alkalinity. Conductivity correlated significantly with TDS and alkalinity. The result of correlation study shows that the bacterial abundance increases with an increase in air and water temperature, conductivity, TDS and alkalinity. However, phytoplankton abundance decreases with an increase in air and water temperature. The load of aerobic heterotrophic bacteria clearly shows a significant level of microbial pollution in the pond. In this study, the inverse relationship between bacterial and phytoplankton could be explained in a way that the excretion of organic compounds from the phytoplankton primary production stimulated the growth of bacteria. In the whole system, the dilution caused by rainwater and the incoming pollutants from the nearby sources also affected the water quality of the pond.

Knowledge Management: Journal