Two Decadal Changes in the Major Ions Chemistry of Melt Water Draining from Dokriani Glacier, central Himalaya, India

• Published in: Journal of the Geological Society of India Vol. 97; no. 3; pp. 308 - 314
• Main Authors: Sundriyal, Shipika, Bhan, Uday, Selvakumar, S., Singh, Rajesh, Dobhal, D. P.
• Format: Journal Article
• Language: English
• Published: New Delhi Geological Society of India 01-03-2021; Springer Nature B.V
• Subjects: Anions; Anthropogenic factors; Atmospheric precipitations; Bicarbonates; Calcium; Calcium ions; Carbonates; Cations; Drainage; Earth and Environmental Science; Earth Sciences; Geology; Glaciers; Hydrogeology; Ion concentration; Magnesium; Meltwater; Precipitation; Rivers; Silicates; Sodium; Water chemistry; Weathering; India
• ISSN: 0016-7622; 0974-6889
• DOI: 10.1007/s12594-021-1682-6

Present study aims to understand the hydrochemical changes in proglacial meltwater stream emerging from the termini of Dokriani Glacier, central Himalaya, India. The major ion concentration of melt water between the years 1994–2015 has been reassessed to infer the glacial/subglacial weathering induced ionic release from Dokriani glacier system. The results from meltwater data collected during post-monsoon period (October 2015) shows that Ca
2+
is more dominant cation followed by Mg
2+
, K
+
, Na
+
and SO
4
2−
is most dominant anion followed by HCO
3
−
and Cl
−
. Scatter plot between Ca
2+
+ Mg
2+
vs total cations shows the overall dominance of carbonate weathering whereas Na
+
+K
+
vs total anions shows high positive relation suggesting domination of both carbonate and silicate weathering. By comparison, the ionic concentration for the year 2015 suggests a significant increase since 1994; however, the discharge weighted concentrations could provide more detailed estimates. An increasing trend in major cations viz. calcium (Ca
2+
) and magnesium (Mg
2+
) while the bicarbonate (HCO
3
−
), sulphate (SO
4
2−
) and nitrogen (NO
3
−
) has been observed as major anion. Further, the source of Cl
−
, NH
4
+
, and NO
3
−
in the meltwater stream is mainly derived from the atmospheric precipitation, anthropogenic, and weathering process. The process of carbonate weathering and dissolution of rock is ascertained as the one which regulates the melt water chemistry.