玉龙雪山浅冰芯pH值对冰川作用区降水量变化的响应

玉龙雪山10.10 m浅冰芯的pH和电导率(EC)变化分析以及与Ca2 、 Mg2 、 K 和Na 浓度的对比表明, 玉龙雪山主要受局地碱性陆源物质的控制.与丽江气象台站的降雨量资料比较发现, 在海洋性冰川区浅冰芯pH和电导率的变化与降雨量和周围地表可溶性离子的输入量关系密切, 并与降雨量呈显著的负相关关系.结合玉龙雪山主要由局地来源补给的特征, 引入TSP(总悬浮颗粒物)作为局地可溶盐补给能力的代用指标分析玉龙浅冰芯pH值对降水量年际变化的响应.在相对湿润年, pH值较低, 若TSP值较高, 则pH值相对较高, TSP值较低, 则pH值较低.在相对干旱年, pH值较高, 若TSP值较高, pH值较高, 若TSP值较低, 则pH值相对较低;在海洋性冰川区, 浅冰芯pH和电导率的变化, 并结合TSP能够有效的反映出冰川作用区干湿的年际变化, 是大气环境状况的敏感指示器.

The Response of pH Value in Ice Core to Precipitation in the Mt. Yulong

Based on an analysis of pH and electrical conductivity(EC) recorded in a 10.10 m ice core from Mt. Yulong, compared with major ion concentrations and observation of TSP and precipitation at Lijiang Station, it is concluded that snow chemistry over the Yulong Glacier is controlled by the local land-based alkaliscent sources. Variations of pH and electrical conductivity in ice core record mainly depend on precipitation and the input of dissolved species. In fact, it is due to the displacement reaction of hydrogen ions and electropositive cation. Taking precipitation as an indicator of the dry and wet year and TSP as an indicator of the sources of dissolved salts, the following conclusions can be drawn: In wet years, high pH value corresponds with high TSP, and vice versa. However, in dry years, low pH values correspond with low TSP. Most important of all, the Yulong Glacier is mainly supplied by the local resources. Thus, the wet and dry history for the temperate glacier environment can be reconstructed. Therefore, pH value and EC, not only in continental glaciers but also in temperate glaciers, are always good indicators of atmospheric environment when TSP is considered.