Environmental significance of snowpit chemistry in the typical monsoonal temperate glacier region,Baishui glacier no. 1, Mt Yulong,China

Samples were collected from two snowpits in Baishui glacier no. 1, Mt Yulong, China, in May 2006. Snowpit chemistry was studied, using ion tracer techniques, HYSPLIT model, factor analysis, correlation and trend analysis. It indicated that total cation concentration is higher in 4,900-m snowpit than in 4,750-m snowpit, whereas total anion concentration is higher in 4,750-m snowpit. Cations, especially Ca²⁺, dominate ionic concentrations in Baishui glacier no. 1. According to correlation analysis and factor analysis, ions can be categorized as follows: Cl⁻ and NO₃ ⁻ as Group 1, SO₄ ²⁻ as Group 2, Mg²⁺ and Ca²⁺ as Group 3, Na⁺ as Group 4, K⁺ as Group 5. Contribution made by terrestrial dust to ionic concentration accounts for 52.27, 100, 99.36, 98.91, 96.16 and 99.97% of Cl⁻, NO₃ ⁻, SO₄ ²⁻, K⁺, Mg²⁺ and Ca²⁺, respectively, in 4,900-m snowpit, and for 64.00, 100, 99.57, 98.63, 96.25 and 99.97% in 4,750-m snowpit. Local dust is the principal source of snowpit chemical components. Pollutants brought from industrial areas of South Asia, Southeast Asia and South China by monsoonal circulation also makes some contribution to anion concentrations, but pollution associated with human activities makes a very slight contribution in study area. The chemical characteristics of two snowpits are different owing to the difference of deposition mechanism and local environment in different altitudes.