title: Factors affecting the spatial pattern of nitrate contamination in shallow groundwater.
abstract: The elevated level of nitrate in groundwater is a serious problem in Korean agricultural areas. To control and manage groundwater quality, the characterization of groundwater contamination and identification of the factors affecting the nitrate concentration of groundwater are significant. The characterization of groundwater contamination at a hydrologically complex agricultural site in Yupori, Chuncheon (Korea) was undertaken by analyzing the hydrochemical data of groundwater within a statistical framework. Multivariate statistical tools such as cluster analyses and Tobit regression were applied to investigate the spatial variation of nitrate contamination and to analyze the factors affecting the NO3-N concentration in a shallow groundwater system. The groundwater groups from the cluster analysis were consistent with the land use pattern of the study area. The clustered group of a gentle-slope area with lower elevations showed higher NO3-N contamination of groundwater than groups on a hillside with higher elevations. Tobit regression results indicated that the agricultural activity in the vegetable fields and barns were the major factors affecting the elevated NO3-N concentration while the land slopes and elevations were negatively correlated with the NO3-N concentration. This shows that topographic characteristics such as land slopes and elevations should be considered to evaluate the land use impact on shallow groundwater quality.
authors.affiliation: School of Earth and Environmental Sciences (BK21 SEES), Seoul National University, Seoul 151-747, Korea.
authors.forename: Dugin
authors.initials: D
authors.lastname: Kaown
authors.forename: Yunjung
authors.initials: Y
authors.lastname: Hyun
authors.forename: Gwang-Ok
authors.initials: GO
authors.lastname: Bae
authors.forename: Kang-Kun
authors.initials: KK
authors.lastname: Lee
mesh_terms: D016000:Cluster Analysis; D004784:Environmental Monitoring; D009566:Nitrates / Q000032:analysis*; D009584:Nitrogen / Q000032:analysis; D012044:Regression Analysis; D012987:Soil / Q000032:analysis; D014872:Water Movements; D014873:Water Pollutants / Q000032:analysis*; D014876:Water Pollution / Q000706:statistics & numerical data
chemical_list: D009566:Nitrates; D012987:Soil; D014873:Water Pollutants; D009584:Nitrogen