Abstract
Studies on the impact of distillery and agricultural pollution on physico-chemical and biological features of three
natural reservoirs (beel) of Rangpur in Bangladesh were conducted from January 2004 to December 2005 under
three treatments: Treatment-I in the distillery polluted Nandinar beel, Treatment-II in the agricultural runoff
polluted Chapundaha beel and Treatment-III in the minimal polluted Dariar beel. Samples were collected from
three locations of each of the beels monthly except heavy metals and soil quality parameters, which were collected
quarterly. Water quality assessment indicates that Nandinar beel water was badly polluted with distillery effluent
and characterized by low dissolved oxygen (0.10-7.50 mg/L), very low nitrate nitrogen (0-0.02 mg/L), high level
of ammonia (0.13-8.45 mg/L), very high chemical oxygen demand (43.64-939.13 mg/L) and high total alkalinity
(24-660 mg/L) with frequent fish kill, while that of Chapundaha beel showed moderately bad water quality having
occasional fish kill and that of Dariar beel had good water quality with no fish kill. The highest organic carbon
(4.46-7.44%), the highest NH4-N (12-41 mg/100 g), the highest NO3-N (2.4-4.45 mg/100 g), with considerable
available phosphorus (0.74-1.27 mg/100 g) and available sulphur (2.2-2.92 mg/100 g) in the Chapundaha beel soil
indicated its higher organic load and productivity than that of Nandinar beel with moderate values of the same and
that of Dariar beel with lower values. Though the Dariar beel was comparatively poor in terms of soil quality yet it
was productive than the Nandinar beel, which might be because of adverse effect of distillery effluent in the
Nandinar beel. The highest concentration of As (6.59-12.71 ppb), Cd (0.003-0.019 ppm) and Zn (0.042-0.357
ppm), and moderate concentration of PЬ (0.009-0.109 ppm), Mn (0.030-0.769 ppm) and Cu (0.004-0.098 ppm) in
the Chapundaha beel might be resulted from the runoff of beel catchments, while that of Dariar beel had the lowest
concentration of As (5.16-10.88 ppb), Pb (0.003-0.049 ppm), Cd (0.001-0.013 ppm), Cu (0.008-0.051 ppm) and
Zn (0.021-0.163 ppm) while a little bit higher concentration of Mn (0.033-0.878 ppm) than that of Nandinar beel
where moderate level of heavy metal concentrations were found. Similarly the concentration of soil As (1000-
6300 ppb), Cd (0.1-0.95 ppm), Cu (25.85-76.30 ppm), Zn (49.25-264.95) except Pb (0.60-17.9 ppm) and Mn
(42.55-334.45 ppm) were the highest in the Chapundaha beel while the Dariar beel had the lowest concentration of
As (mean 1413.46 ppb), Pb (mean 5.98 ppm), Cd (mean 0.26 ppm), Cu (mean 27.64 ppm) and Zn (mean 69.94
ppm) and the Nandinar beel had the moderate concentration of soil heavy metals. Heavy metal concentration was
found to vary more or less proportionately with the beel catchment areas. The highest and diverse (H=1.03)
abundance of phytoplankton (8-37.4X104 cells/L) as well as total plankton (8.2-37.4X104 cells/L) with moderate
zooplankton density (0-2.85X101 cells/L) as recorded in the Chapundaha beel was an indication of eutrophication,
while the Dariar beel was with moderate phytoplankton abundance (5.3-29.4X104 cells/L) and the Nandinar beel
with poor abundance of phytoplankton (2.6-26.85X10 cells/L) as well as total plankton (2.6—27.5X104 cells/L)
with the lowest species diversity (H=0.93) might be the consequences of degraded habitat due to distillery effluent
deposition. Higher abundance of chironomids (79.02%) with absence of some other insect larvae
(ceratopogonidae, odoneta, ephemeroptera) along with lower species diversity (H=0.75) and species richness (9) in
the Nandinar beel indicated its poorest environmental condition while presence of considerable number of insect
larvae with more or less diverse other benthic fauna (H=1.05) in the Dariar beel was an indication of better
environmental condition and that of Chapundaha beel which was moderate in terms of macrobenthic organism.
The presence of numerous fungal granuloma and necrotic lessions in muscles were indicative of epizootic
ulcerative syndrome led histological alterations of different organs in the investigated fishes of Chapundaha beel
while degenerative changes without fungal granuloma in the fishes of Nandinar beel were probably due to the
consequences of distillery effluents and no degenerative changes in the fishes of Dariar beel round the year
signified its suitable environmental condition. Socio-economic status of the fishermen of Nandinar beel
characterized by low annual income (Tk.17,921.74), the lowest land ownership (0.21 acre), poor housing, poor
health and sanitary facility with low fish consumption (35.2 g/capita/day) while that of Chapundaha beel
fishermen was better and that of Dariar beel was moderate to higher in terms of high fish consumption (50.5
g/capita/day), higher annual income (Tk.23,175.00), liteacy, etc. Distillery effluent deteriorated physico-chemical
characteristics of water and soil; exerted deleterious effect on plankton, benthos and fishes remarkably with severe
oxygen depletion and fish kill. Very mild pollution due to only agricultural runoff from the adjacent areas of the
beel paves the way of eutrophication resulting in higher productivity with occasional risk of oxygen depletion,
disease and fish kill. Unpolluted fish habitat, leads moderate productivity generally with no risks of fish kill and
diseases along with diversified aquatic flora and fauna. Distillery effluents along with other pollutants had also
adverse impact on aquatic birds, vegetation and socio-economic condition of the community. However, further
research in wider areas for a longer period may strengthen the present findin