He Stable Hydrogen And Oxygen Isotope Analysis Of Heilongtan Karstic Spring In Kunming

Water is the source of life, is the basic condition for human survival and development, is the important and active factor in natural environment and social environment, is the foundational natural resource and strategic resources to maintain the earth ecosystem function and support the development of social economy system which can not be replaced by. As we know, China, because of its huge population, has less than a quarter of the world’s average per capita water capacity. Karst water is an important part of the groundwater resources, and it accounts for a quarter of the amount of groundwater resources.In karst regions, karst water is a very important source for the domestic and industrial water use.In karst regions, the groundwater often discharges to the surface in the form of spring.But because of the complexity and anisotropy of the karst aquifer, the limitations of traditional research methods always make it hard to figure out the groundwater hydrologic system.This study using hydrogen and oxygen stable isotope method, periodic sampling analysis of atmospheric precipitation and spring water(including Xiaoshuitan,Qingshuitan and Hunshuitan) let me get a lot of first-hand basic data.These data is very helpful for the research of the characteristics and change rule of the groundwater hydrologic system in the study area.In addition, this three karst springs are located at the the edge of the basin-rifted in plateau, there is little research on it at home and abroad.The study of its hydrological characteristics lays a solid foundation for the future study, is of important theoretical and practical significance.Here we present the results of the first systematic analysis of the hydrogen and oxygen stable isotope composition of the karst hydrological systems in the Heilongtan.And the main conclusions are as follows:1.Analysing the relationship of δ18O and δD in atmospheric precipitation and setting up the local meteoric water line.The analysis of the hydrogen and oxygen stable isotope composition of atmospheric precipitation and spring indicates that the groundwater is from the atmospheric precipitation.Specifically,the hydrogen and oxygen stable isotope composition of spring indicates that summer precipitation is dominated in the aquifer recharge.2.Gaussian mixture modelling applied using the hydrogen and oxygen stable isotope compositions of the karst groundwater. And it revealed that the aquifer of recharge area for the Qingshuitan and Hunshuitan is of duality significantly, contains fissure-porous aquifer and karstic channels.Accordingly, they have a high degree of karst development.in addition, they have some common properties in base flow,so we infer that they have the same source or same recharge elevation.The hydrological system of Xiaoshuitan is relatively single, karst development level is low.3.The lumped parameter model is applied to simulate the groundwater transit and calculate the transit time which is1.8、5.8、5.4weeks for Qingshuitan,Hunshuitan and Xiaoshuitan.Using a variety of mathematical statistical models for the analysis of the hydrogen and oxygen stable isotopic compositions, we almost get the same conclusion.So it is reliable. And we hope that this work will provide new insight into the hydrogeological characteristics of the study area.