典型岩溶泉主要化学成分来源及地球化学敏感性研究

Study on sources of chemical elements and geochemical susceptibility of a typical karst spring

为定量研究岩溶区突出的地球化学敏感性和脆弱性,引入地球化学敏感指数概念,以重庆金佛山水房泉为例,利用2016年1月至12月观测的水化学数据,对水房泉的主要化学成分来源及地球化学敏感性进行研究。结果表明,水房泉水化学类型为Ca-HCO_3型和Ca-HCO_3·Cl型;岩溶作用与人类活动综合影响下,HCO_3^-、Cl^-和Ca^(2+)成为研究区主要阴阳离子,Cl^-主要来源于人类旅游活动造成的污染物,SO_4^(2-)主要来源于硫酸型酸雨沉降;岩溶作用的季节变化使得HCO_3^-、Ca^(2+)成为敏感指数最高的阴阳离子;水房泉的宏量元素地球化学敏感性指数在旅游活动影响下,除NO_3^-外均有不同程度的升高,其敏感性指数依次为HCO_3^->Ca^(2+)>Na^+>SO_4^(2-)>Cl^->NO_3^-=K^+>Mg^(2+)。受人类活动影响,岩溶泉水化学表现的更为敏感,减少并净化人类活动污染物、增强游客环保意识等措施对岩溶泉的保护至关重要。

To quantitatively study the prominent geochemical susceptivity and vulnerability of a karst spring in typical karst areas,the geochemical susceptibility and sources of chemical elements in Shuifang Spring,Jinfo Mountain in Chongqing was analyzed by using hydrochemical data from January 2016 to December 2016.The results show that chemical types of Shuifang Spring were Ca-HCO3 and Ca-HCO3·Cl.Under the combined influence of karst processes and human activities,the major anions and cation were HCO^-3,Cl^-and Ca^2+.Cl^-mainly come from human pollutants caused by tourism activity,and SO^2-4 mainly comes from the effects of sulfuric acid rain.Due to seasonal change of karst processes,HCO3^-and Ca^2+became the most sensitive ions.Under the influence of tourism activities,the geochemical susceptivity for major elements except for NO^-3 in Shuifang Spring has increased in the order of HCO-^3 >Ca^2+ >Na+ >SO^2-4 >Cl^- >NO^-3=K+ >Mg^2+.The chemical features of karst spring are more sensitive because of human activities.Measures such as reducing and purifying the pollutants of human activities,improving the awareness of environmental protection of tourists and other related measures are strongly suggested for the protection of karst spring.