251. Hydrogeochemical Analysis of Phewa Lake: A Lesser Himalayan Lake in the Pokhara Valley, Nepal
- Author
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Udhab Raj Khadka and AL. Ramanathan
- Subjects
eutrophication ,lake characteristics ,major ion ,trophic status ,weathering ,Environmental technology. Sanitary engineering ,TD1-1066 ,Environmental sciences ,GE1-350 - Abstract
Phewa Lake in Nepal is a lake of international importance providing crucial ecological and economic services. However, increased urbanization, population growth and anthropogenic activities have resulted in degradation of the lake. Thus, understanding the lake hydro-geochemistry is crucial for identifying sources of elements. Preceding studies have mostly covered limnological and physico-chemical assessments which are not sufficient to explain the lake catchment characteristics. This study has assessed the major ions in relation to their hydro-geochemical processes in the catchment. To evaluate monsoonal impact, the rainwater was also analyzed. The major ions were determined by using standard methods. The results revealed significant seasonal variations in temperature, pH, TDS, EC, and most of the major ions. There was domination of the total anions (Tz-) over the total cations (Tz+) indicating possible ionic contribution through decomposition of organic compounds. The domination of Ca2+, Mg2+ and HCO3- elucidates influence of carbonate weathering. The high (>1) equivalent ratio for (Ca2++Mg2+)/(Na++K+), and (Ca2++Mg2+)/(Tz+) ratio ≈1 also suggest abundance of (Ca2++Mg2+) and prevalence of carbonate weathering. The low (
- Published
- 2021
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