Abstract
Uma Oya, which has the highest watershed of the Upper Mahaweli discharges into Rantambe reservoir. Uma Oya may have been polluted as it drains a large portion of agricultural lands. A preliminary study was conducted from April to October, 2007 sampling six randomly selected sites to determine the status of water quality of Uma Oya as baseline data. pH, water temperature, dissolved oxygen, electrical conductivity and turbidity were measured in situ, whereas the processed water samples were brought to the laboratory to determine using standard methods, nitrate-N, nitrite-N, ammoniacal-N, ortho-phosphate, total suspended solids and chlorophyll-a content. Many water quality parameters were within the tolerance limits for fish and other aquatic life. However, the Chlorophyll-a (19.93±10.4 µg/L) was slightly higher than the standard guidelines perhaps due to epilithic algae washed off from bed rocks under high water flow. Total suspended solids (17.87±17.96 mg/l) and turbidity (37.84±59.88) were higher than the standard limits for fish and aquatic life, indicating high suspended solids transported by Uma Oya water. Further studies are required in relation to the cultivation pattern of the water shed to get a clear picture about Uma Oya.
Highlights
The riverine habitats are among the major economically important and biologically rich ecosystems in Sri Lanka
Mean total suspended solids (17.87±17.96 mg/l) and turbidity (37.84±59.88) were higher than the standard limits for fish and aquatic life, indicating high suspended solids are transported by Uma Oya water
Results revealed that the mean value of pH, dissolved oxygen, electrical conductivity and nitrate-N were within the limit of proposed ambient water quality standards for inland waters of Sri Lanka (CEA 2001) for all sampling locations
Summary
The riverine habitats are among the major economically important and biologically rich ecosystems in Sri Lanka. Many riverine habitats of Sri Lanka rapidly altering through many anthropogenic activities such as improper use of agrochemicals, damming, discharging various waste materials, industrial effluents and deforestation (UNEP 2001). The report further stated that pollution, 32 K.A.W.S. Weerasekara et al./Sri Lanka J. Sci. 20 (2) (2015): 31-38 sedimentation, eutrophication, degradation of the ecosystem and excessive growth of aquatic weeds can be considered as the main threats to aquatic ecosystems in Sri Lanka. Recent studies suggested that many waters are deteriorating rapidly in Sri Lanka (Azmy et al 2010; Gunawardena et al 2010; Hewawasam 2010; Watawala et al 2010)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
