重庆金佛山地区岩溶泉水遍布,但是各个泉点的水质却有较大差异.利用地下水的化学性质,如pH,电导率γ,HCO3-、Ca2+、Mg2+、Na+、K+、SO42-、NO3-和Cl-等的质量浓度进行因子分析可以分辨出自然过程和人类因素对地下水的影响.2009年1月在重庆金佛山地区采集36个岩溶泉水样,分析结果表明:金佛山岩溶泉的水化学成分具有较大的空间变异.利用SPSS中因子分析方法,得到基于水中离子和地球化学过程解释的地下水水质特征及其形成的4个因子:水-岩作用是地下水中SO42-、F-、K+、Sr2+和Ca2+形成的共同因素,Mg2+、HCO3-主要受土壤等因子影响,Na+、Cl-主要来源于大气降水,人类活动主要影响水中的NO3-.以上4种因子可以解释金佛山岩溶地下水水质形成的87.58%,其中水-岩作用可以解释55.56%,是影响金佛山地区岩溶水水质的最重要因素.
Epikarst springs which show large variations in water quality abound in the Jinfo Mountain, Chongqing. In order to find out the influence factors, an attempt was made to distinguish the natural and anthropogenie processes and factors responsible for groundwater quality. R-mode factor analysis was applied for the sets of chemical data, i.e. pH, 7, p(HC03- ), P(ca2+ ), p(Mg2+ ), P(Na+ ), P(K+ ), p(S042- ), p(N03- ) and p( C1- ) in the karst springs at Jinfo Mountain. Groundwater samples were collected at 36 sites in January, 2009. Analytical results of these groundwater samples show the springs at Jinfo Mountain had variable chemical composi- tions. By applying the R-mode factor analysis of SPSS, four factors were obtained, which could help to explain the characteristics of groundwater quality and to identify the formation of hydroehemistry based on the performance of ions and their geochemical processes. The water-rock interaction in karst area is the common influence factor for S042- , F- , K+ , Sr2+ and Ca2. in groundwater. Concentrations of Mga+ and HC03- are highly related to soil. Precipitation should be responsible for concentrations of Na* and C1-. Anthropogenic activities contribute to elevation of NO3 in groundwater. The four factors can explain for 87.58% of the formation of karst groundwater. The naturalprocesses are the most important influence factors for the formation of groundwater quality in the springs of Jinto Mountain, including 55.56% attributed to the processes of water-rock interaction. It means that factor analysis is useful in analysing water quality and illustrating its influence factors as well as in evaluation of water quality.