Hydrochemical patterns indicating hydrological processes with the background of changing climatic and environmental conditions in China: a review.

Abstract

In the background of global climate and environmental change, the hydrochemical characteristics of water bodies present significant instability to all regions, including humid, arid, and alpine ones. There are two main reasons for this: (1) climate change has altered the temporal and spatial distribution of precipitation, and climate warming intensified the mutual transformation of water bodies. The temperature in China increased by 0.29°C/10a from 1951 to 2018. For different regions, whether the alpine region (0.37°C/10a, P < 0.05), the arid region (0.278°C/10a, P < 0.05), or the humid region (0.168°C/10a, P < 0.05), there was a significant increasing trend (P < 0.05) from 1951 to 2018. Thus, the characteristics of water recharge sources and the hydrological processes and hydrochemical characteristics of water bodies are affected. Increase in precipitation increases the input sources for water transformation, intensifying the transformation of water bodies. (2) In the context of climate and environmental change, human activities and the local environment are seriously affecting the transformation of various water bodies and hydrochemical ion sources. The comprehensive effects of various physical and geographical conditions, geological structure, lithology and transformation, and recharge of various water bodies affect the hydrochemical characteristics of water bodies in China. The differences in the type of water bodies showed that the hydrochemical process of water bodies was more complex, although there was a hydraulic connection between precipitation, river water, lake water, and groundwater. This provides a new idea for the future study of hydrochemical characteristics and hydrology.