Spatial characterization of dissolved trace elements and heavy metals in the upper Han River (China) using...

Area of Science:

• Environmental Science
• Geochemistry
• Water Quality Assessment

Background:

• The upper Han River's water quality is crucial due to its ecological and potential human impact.
• Understanding the spatial distribution of trace elements and heavy metals is vital for effective environmental management.

Purpose of the Study:

• To spatially characterize dissolved trace elements and heavy metals in the upper Han River.
• To identify primary pollution sources (anthropogenic vs. geogenic) affecting water quality.

Main Methods:

• Utilized multivariate statistical techniques: cluster analysis, principal component analysis (PCA), factor analysis (FA), correlation analysis, and analysis of variance.
• Analyzed a dataset of 4032 observations from 42 sampling sites over a 2-year period (2005-2006).

Main Results:

• Identified Al, As, Cd, Pb, Sb, and Se as primary pollutants; Ba, Cr, Hg, Mn, and Ni as potential pollutants.
• Spatial analysis indicated concentrated pollution in Danjiang, Danjiangkou Reservoir catchment, and Hanzhong Plain, with Hanzhong Plain being the most contaminated.
• Cluster analysis grouped sites into four quality regions: headwaters (very high pollution), Danjiang (moderate pollution), lower catchment (moderate pollution), and upper catchment (low pollution).

Conclusions:

• Trace metals like Al, Cd, Mn, Ni, Fe, Si, and Sr are primarily from natural sources.
• Other identified metals are mainly influenced by human activities, although natural sources also contribute.
• The study provides a detailed spatial assessment of heavy metal pollution in the upper Han River.