Isotopic Effect and the Deuterium Excess Parameter Evolution in Ice and Snow Melting Process:A Case Study of Isotopes in the Water Body of Daocheng,Sichuan Province

The variation of water isotope composition is actually an integrated reaction depending on the change of environment. The ice and snow melt of different seasons in high mountains can obviously affect the variation in isotope composition and deuterium excess parameters of surface flow and shallow groundwater. The knowledge of the isotopic fractionation caused by this special natural background and the exploration of its formation and evolution are extremely important in estimating the relationship between the environment,climate and water resources in a certain area. With the isotope composition of surface flow and shallow groundwater in Daocheng of Sichuan as an example,this paper deals mainly with the variation regularity of the isotope composition and the deuterium excess parameters of surface flow and hot-spring under the condition of ice and snow melt in high mountains during different seasons. The isotope effect and the deuterium excess parameter evolution in the process of ice and snow melting are also discussed in detail.