Salt lakes are important in global hydrological and biogeochemical cycles, accounting for approximately 44% of the total lake water volume worldwide. Water salinity serves as the key variable regulating physical, ecological, and chemical processes in these systems, playing a decisive role in regional ecological security and the sustainability of water resources.

However, both climate change and intensifying human activities are altering the water salinity of these vital ecosystems, according to a comprehensive new study published in Earth-Science Reviews.

Led by researcher Prof. SONG Chunqiao from the Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, the study presents an interdisciplinary review of the spatiotemporal dynamics, monitoring technologies, and socio-environmental consequences of salt lake salinity.

The research team synthesized global records to analyze the evolution of monitoring methods. They noted a significant transformation from traditional point sampling to large-scale, long-term dynamic monitoring systems centered on satellite remote sensing and machine learning. The study reveals a highly heterogeneous spatial pattern of water salinity changes globally. While global salt lakes are predominantly distributed across arid and semi-arid zones, they are currently experiencing strongly divergent evolutionary trajectories.

The researchers found that salt lakes in arid regions are frequently undergoing aggravated salinization, primarily driven by agricultural irrigation and increased aridity. Conversely, high-altitude salt lakes, particularly those on the Tibetan Plateau, exhibit significant desalination due to increased water volumes and glacial melt associated with a warming and wetting climate.

These dynamic shifts in salinity exert cascading impacts across socio-ecological systems. The study details how altered salinity dynamically reshapes food web structures, regulates physical stratification and elemental cycling, and ultimately exerts severe impacts on soil salinization, drinking water safety, and critical infrastructure across watersheds.

“These findings underscore the profound vulnerability of salt lake ecosystems to global environmental changes and local human interventions, emphasizing the need to move beyond mere monitoring toward predictive modeling of future salinity changes.” said by Prof. Song.