The bed Shakla, comprising an average area of 75.0 ha is located in the northeastern
region (Brahmanbaria district) of Bangladesh. The study was carried out to assess the
ecological aspects of bed ecosystem. Surface run-off and increase inflow of rain water
from the upper stretch during monsoon cause inundation and resumption of connection
between beel and parent rivers. The range of dissolved oxygen (DO) content ( 4.5-8.9
mg/L) was found congenial for aquatic life. pH was in the alkaline range (7.3-8.5) and
free C02 was reletavely high. Lower values of total hardness and total alkalinity indicated
less nutrients in the beel water. A wide variation (1.4-27.2 x 103 ceHs/L) in the standing
crop of total plankton was recorded during study period of which phytoplankton alone
contributed about 90%. Phytoplankton diversity in the beel represented by three groups
viz. Chlorophyceae, Myxophyceae and Bacillariophyceae in order of abundance. A total
of 52 fish species belonging to 36 genera, 20 families and 1 species of prawn were
identified so far from the beel. About l3 types of fishing method were found in
operation. Seine nets (moshari berja, ghono berjal) and gill net (current jal) were
identified as detrimental gear killing juveniles of different species during post spawning
period. Kua fishing was also found harmful due to dewatering nature. A total of 11
species belonging to 11 genera and 10 families of aquatic weeds were identified from the
beet The eggs of Macrobrachium Jamarrei were identified into the Najas najas vegetation
during April-September
