岩溶水水化学特征的主成分分析和因子分析

【目的】为了解岩溶区地下水水化学特征以及地下水成分的来源。【方法】以广西果化镇地下水为研究对象,于2017年7月共采集地下水样品21件,运用Gw_chart软件制作水化学Piper三线图,结合R软件进行相关性分析、主成分分析法、因子分析法等对数据进行处理。【结果】研究区岩溶地下水水化学类型主要为重碳酸-钙型水,Ca2+和Mg2+为地下水中主要阳离子,HCO-3和SO2-4为地下水中主要阴离子。HCO-3与Ca2+,Na++K+与Cl-,SO2-4与Mg+2、Ca2+,相关性较强,它们经历了相似的化学反应过程。通过主成分分析法提取了3个主成分,共解释了91%的方差,可以很好地代表原始数据;通过因子分析提取出3个公共因子,共解释了86%的方差。【结论】自然因素水-岩作用为水化学元素特征与来源主导因素,人类活动也起到了重要作用。

Principal Component Analysis and Factor Analysis of Chemical Characteristics of Karst Water

Objective] In order to understand the chemical characteristics of groundwater and the source of groundwater components in karst areas, the groundwater samples from Guohua town of Guangxi Province were taken as research objects. In July 2017, a total of 21 groundwater samples were collected.Methods] The Gw_chart software was used to make the three-line diagram of the water chemistry Piper, and the R software was used to process the data by correlation analysis, principal component analysis and factor analysis.Results] The study found that the karst groundwater hydrochemical type in the study area was mainly bicarbonate-calcium water, Ca²⁺ and Mg²⁺ were the main cations in groundwater, and HCO₃^- and SO₄^2- were the main anions in groundwater. HCO₃^- is highly correlated with Ca²⁺, Na⁺ +K⁺ and Cl^-, SO₄^2- and Mg²⁺, Ca²⁺, and they undergo a similar chemical reaction process. Three principal components were extracted by principal component analysis, which explained 91% of the variance and represented the original data well. The three common factors extracted by factor analysis explained 86% of the variance.Conclusion] Natural factors water-rock action is the dominant factor of water chemical element characteristics and source, and human activities also play an important role.