Hydrochemical Characteristics and Controlling Factors of Typical Dolomite Karst Basin in Humid Subtropical Zone

A unique hydrochemical profile distinguishes dolomite karst basins in humid subtropical zones, marked by HCO3-Ca·Mg type water, unlike the HCO3-Ca type found in limestone or shale areas. A study of 215 water samples from the Shanmuhe and Huangzhouhe Basins within China's Shibing Dolomite Karst World Natural Heritage Site revealed that ion concentrations like EC, Ca²⁺, Mg²⁺, HCO3⁻, and their ratios increase as water transitions from allogenic upstream regions to dolomite karst areas downstream. Seasonal variations show minimal fluctuation in ion concentration, with slight dilution during rainy seasons, while rainfall import remains low, indicating limited human impact on hydrochemistry. The research highlights that geological factors, particularly lithology, primarily control water chemistry through rock weathering and water-rock interactions.

Xiao, S., Zeng, C., Lan, J., Di, Y., He, J., Xiao, H., & Wang, J. (2021). Hydrochemical Characteristics and Controlling Factors of Typical Dolomite Karst Basin in Humid Subtropical Zone. Geofluids, 2021, 1–14. https://doi.org/10.1155/2021/8816097