Dissolved and Sediment Load Characteristics of Kafni Glacier Meltwater, Pindar Valley, Kumaon Himalaya

An analytical study on major cations (Ca, Mg, Na, K) and anions (HCO₃, SO₄, Cl) in the meltwaters draining from Kafni glacier, Pindar valley, were carried out in the present study. The analysis was directed towards the deciphering, of the major ion chemistry, the diurnal variation in solute and suspended sediment concentrations and to trace the source and mechanism controlling water chemistry of Kafni meltwaters. Distinct diurnal variation has been observed by major ionic species and suspended sediment concentration in the meltwater, reflecting varying proportions of meltwater transferred to the channel through different routes. Among cations Ca is the most dominant ion (69%) followed by Mg (19%), Na (8%) and K (4%). Bicarbonate is the dominant anion, constituting 85% of the total anions and 61% of TDS. The hjgh concentration of bicarbonate and its good correlation with Ca indicates their common source, from the dissolution of carbonate rocks. The high (Ca+Mg)/(Na+K) ratio i.e. 8, the high contribution of (Ca+Mg) to the total cations (Ca+Mg/TZ⁺ = 0.9) and low ratio of (Na+K)TZ⁺ = 0.11 also suggests that the carbonate weathering could be the primary source of major ions in these waters. The suspended sediment concentration negatively correlated with IDS and the increasing TSM/TDS ratio with the discharge indicate prominence of physical weathering over chemical weathering in the afternoon time.