In the heart of China’s Yunnan Province, a region known for its mountainous terrain and abundant water resources, a comprehensive study has shed new light on the dynamics of groundwater resources. Led by Yu Gao from the Yunnan Key Laboratory of Geohazard Forecast and Geoecological Restoration in Plateau Mountainous Area, the research provides a detailed evaluation of groundwater resources, offering valuable insights for regional water management and planning.
Yunnan Province, situated in the eastern region of the Qinghai-Tibet Plateau and the western area of the Yunnan-Guizhou Plateau, is characterized by its mountainous plateau topography. The province is rich in water resources, with groundwater holding significant potential for development and utilization. However, the uneven spatial distribution of these resources poses a critical challenge.
The study, published in *Carsologica Sinica* (which translates to “Karst Science in China”), systematically evaluates groundwater resources by dividing the province into 21 four-level basin systems and 41 five-level units. Utilizing long-term rainfall data from 2000 to 2020, along with hydrogeological surveys conducted since 1960, the research provides a comprehensive assessment of groundwater recharge and runoff resources.
“Our findings indicate that the average annual recharge of groundwater resources from 2000 to 2020 was 85.466 billion cubic meters per year,” explains Yu Gao. “The average annual groundwater runoff resources amounted to 62.916 billion cubic meters per year, accounting for 73.62% of the groundwater resource supply.”
The study highlights significant fluctuations in groundwater resource supply across different basins. The Yangtze River Basin, the river basins of Southwest China, and the Pearl River Basin all exhibited varying levels of groundwater resource supply, with the lowest supply recorded in 2011. The highest supplies were recorded in 2016 for the Yangtze River Basin, 2015 for the Pearl River Basin, and 2008 for the river basins of Southwest China.
Beyond quantity, the research also delves into the quality of groundwater. Monitoring data from 223 water quality points in 2021 revealed that most of the groundwater fell into Class IV and Class V categories, indicating varying degrees of pollution. The primary pollutants included NH4+, F−, Fe, Mn, volatile phenols, Hg, and COD. The study identified economically developed and densely populated cities such as Kunming, Qujing, Yuxi, Kaiyuan, Chuxiong, and Dali as the main areas of pollution.
“This research not only highlights the disparities in groundwater resources across various basins in Yunnan Province but also serves as a crucial foundation for regional water resource management and planning,” says Yu Gao. “It underscores the need for stricter environmental protection policies, stronger monitoring and control of pollution sources, promotion of water-saving technologies, and raising public awareness of environmental protection.”
The implications of this research are far-reaching, particularly for the energy sector. Accurate evaluation of groundwater resources is essential for sustainable development, ensuring that water resources are managed effectively to support industrial and agricultural activities. The findings can guide policymakers and industry stakeholders in making informed decisions about water usage and conservation.
As Yunnan Province continues to develop, the sustainable utilization of groundwater resources will be paramount. This study provides a critical stepping stone towards achieving that goal, offering a roadmap for future research and practical applications in water resource management.