On October 14, in Hefei, China, a significant discovery regarding lithium reserves in China’s largest saline lake, Qinghai Lake, was reported. Experts estimate that the lake’s lithium reserves are expected to stabilize within 1,200 years, with lithium isotope values anticipated to continually rise, ultimately reaching 0.045% in about 6,000 years.

This groundbreaking research was conducted by Professor Xiao Yilin’s team from the University of Science and Technology of China, in collaboration with various institutions, including the Qinghai Lake Scenic Area Protection and Utilization Management Bureau, the Qinghai Institute of Salt Lakes at the Chinese Academy of Sciences, the University of Pennsylvania, and Nanning Normal University. Their findings, which detail the lithium cycling process and isotope fractionation mechanisms in the lake, were recently published in the journal “Applied Geochemistry.”

Qinghai Lake is situated at the intersection of arid, high-altitude, and monsoon regions, making it particularly sensitive to global climate change. With minimal human intervention from population and agricultural activities, the lake serves as a pristine record of paleoclimate information for the Tibetan Plateau.

Lithium isotopes are considered effective indicators of ancient climatic changes. However, to utilize these isotopes for tracing purposes, researchers needed to unravel the mechanisms behind lithium isotope fractionation and elemental cycling in the lake’s water and sediment systems.

The study revealed that the lithium concentration in Qinghai Lake exhibits slight fluctuations, primarily influenced by adsorption processes involving iron oxides or suspended particles, while lithium isotopes display remarkable uniformity. By analyzing the incoming river water, the team was able to construct a lithium cycling model for the lake.

The model indicates that Qinghai Lake is currently in a non-steady-state condition, with lithium input slightly exceeding output. Assuming current climatic conditions remain unchanged, the lake’s lithium reserves are projected to gradually increase and stabilize within 1,200 years, during which the lithium isotope values will also rise until reaching 0.045% over the next 6,000 years.

Researchers noted that, given the striking similarities between Qinghai Lake and marine systems, this study may provide valuable insights into the evolution of marine lithium isotopes, deepening our understanding of the global lithium cycle.