Spatiotemporal Characteristics and Source Apportionment of Hydrochemical Ions in the Main Stream of the Luohe River

Key Points

• The research aims to assess the spatiotemporal distribution and sources of hydrochemical ions in the Luohe River.
• Conducted field surveys and sampling at 11 points along the river in March, June, September, and December 2024.
• Analyzed hydrochemical compositions and their spatial and temporal distribution characteristics.
• Employed PCA-APCS-MLR model for quantitative analysis of ion sources.
• Total nitrogen concentration averaged 2.48 mg·L⁻¹, exceeding water quality standards.
• Concentrations of nitrate and ammonium nitrogen were 2.10 mg·L⁻¹ and 0.47 mg·L⁻¹, respectively.
• Identified three spatial zones of ion concentration with an overall increasing trend; seasonal variation showed lower levels in summer and higher levels in winter.
• Source analysis revealed contributions from mixed, rock weathering, and anthropogenic activities at 23.29%, 31.43%, and 13.83%, respectively.

Abstract