Hatha, A A M; Jesmi, Y; Mujeeb Rahiman, K M; Lal, Deepu; Jyothi, S(National Environmental Health Association, 2013)
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Abstract:
Water quality of rooftop-collected rainwater is an
issue of increased interest particularly in developing countries where the
collected water is used as a source of drinking water. Bacteriological and
chemical parameters of 25 samples of rooftop-harvested rainwater stored
in ferrocement tanks were analyzed in the study described in this article.
Except for the pH and lower dissolved oxygen levels, all other physicochemical
parameters were within World Health Organization guidelines. Bacteriological
results revealed that the rooftop-harvested rainwater stored in
tanks does not often meet the bacteriological quality standards prescribed
for drinking water. Fifty percent of samples of harvested rainwater for rural
and urban community use and 20% of the samples for individual household
use showed the presence of E. coli. Fecal coliform/fecal streptococci ratios
revealed nonhuman animal sources of fecal pollution. Risk assessment of
bacterial isolates from the harvested rainwater showed high resistance to
ampicillin, erythromycin, penicillin, and vancomycin. Multiple antibiotic
resistance (MAR) indexing of the isolates and elucidation of the resistance
patterns revealed that 73% of the isolates exhibited MAR
The water quality and primary productivity of Valanthakad backwater (9° 55 10. 24 N latitude and 76° 20 01. 23 E
longitude) was monitored from June to November 2007. Significant spatial and temporal variations in temperature,
transparency, salinity, pH, dissolved oxygen, sulphides, carbon dioxide, alkalinity, biochemical oxygen demand, phosphatephosphorus,
nitrate-nitrogen, nitrite-nitrogen as well as primary productivity could be observed from the study. Transparency
was low (53.75 cm to 159 cm) during the active monsoon months when the intensity of solar radiation was minimum, which
together with the run off from the land resulted in turbid waters in the study sites. The salinity in both the stations was low (0.10
‰ to 4.69 ‰) except in August and November 2007. The presence of total sulphide (0.08 mg/ l to 1.84 mg/ l) and higher
carbon dioxide (3 mg/ l to 17 mg/ l) could be due to hospital discharges and decaying slaughter house wastes in Station 1 and
also from the mangrove vegetation in Station 2. Nitrate-nitrogen and phosphate-phosphorus depicted higher values and
pronounced variations in the monsoon season. Maximum net primary production was seen in November (0.87 gC/ m3/ day) and
was reported nil in September. The chlorophyll pigments showed higher values in July, August and November with a negative
correlation with phosphate-phosphorus and nitrite-nitrogen. The study indicated that the water quality and productivity of
Valanthakad backwater is impacted and is the first report from the region
Description:
Indian Journal of Marine Sciences
Vol. 39(1), March 2010, pp. 105-113