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2026 Vol.31, Issue 2 Preview Page

Research Article

Integrated PCA-cluster Framework for Classifying Groundwater Level Variation Types in Rural Area

PCA-군집분석 통합 기법을 이용한 농촌지역 지하수위 변동 유형 분류

Sung-Ho Song1*
,
Ga-Young Hwang2
,
Hwan-Ho Yong2
송 성호1*
,
황 가영2
,
용 환호2
1Groundwater and Environment Engineering
2Rural Research Institute, Korea Rural Community Corporation
1㈜지엔이이엔지
2한국농어촌공사 농어촌연구원
*Corresponding Author
30 April 2026. pp. 16-26
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Abstract

This study classified groundwater level variation types in rural areas by analyzing long-term groundwater level time series and hydrogeological variables from 157 monitoring wells. Groundwater level trends and variability were quantified using the Mann-Kendall test and Sen’s slope estimator, and a multivariate dataset including hydraulic conductivity, elevation, depth, hydrogeological unit (HGU), and pumping rates was used to perform hierarchical cluster analysis and principal component analysis (PCA). The cluster analysis identified four distinct groundwater level variation types-persistent decline, stable increase, low variability, and high variability in highly permeable aquifers-reflecting differences in groundwater response to geological, topographic, climatic, and anthropogenic factors. PCA showed that PC1 was dominated by hydraulic conductivity, while PC2 was primarily governed by groundwater level trend with secondary hydrogeologic influences. These components effectively summarized major groundwater variation patterns. Visualization of the four clusters in the PC1-PC2 space showed clear separation among groups, demonstrating that PCA provides a concise and robust framework for distinguishing groundwater level variation patterns in rural monitoring networks.

Keywords
Principal component analysis (PCA)
Hierarchical cluster analysis
Groundwater level variation type
Groundwater monitoring wells
Hydrogeological unit (HGU)
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Information
  • Publisher :The Korean Society of Soil and Groundwater Environment
  • Publisher(Ko) :한국지하수토양환경학회
  • Journal Title :Journal of Soil and Groundwater Environment
  • Journal Title(Ko) :지하수토양환경
  • Volume : 31
  • No :2
  • Pages :16-26
  • Received Date : 2026-03-26
  • Revised Date : 2026-04-06
  • Accepted Date : 2026-04-21
  • DOI :https://doi.org/10.7857/JSGE.2026.31.2.016
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