The dual crisis of saline lakes: when too little – or too much- water threatens survival

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By Egor Zadereev, President, International Society for Salt Lake Research; Member, IUCN Commission on Education and Communication; Research Scientist, Krasnoyarsk Research Center, and Faith Coleman, Board Member, International Society for Salt Lake Research; Co-Founder, Coorong Environmental Trust

Saline lakes are facing a double threat: while some are shrinking due to overuse, others are expanding from excess inflows—both with damaging effects on ecosystems and communities. In this blog, Egor Zadereev and Faith Coleman of the International Society for Salt Lake Research call for urgent, nature-positive solutions. They invite you to join the conversation at the IUCN World Conservation Congress 2025, where challenges like these will take centre stage. 

Unsplash, Carlett Badenhorst

While much of the conversation around saline lakes focuses on their decline and disappearance, there’s another side to the story: some saline lakes are expanding. This might sound like good news, but it’s not. Whether a saline lake is shrinking or growing, the underlying issue remains the same - human activities and climate change are disrupting these ecosystems in ways that threaten their ecological integrity and the communities that depend on them. 

 

The Shrinking Lakes: A Familiar Crisis 

Figure 1: Lake Urmia, December 1984 (left) and December 2020 (right). Source Google Earth.          Figure 1: Lake Urmia, December 1984 (left) and December 2020 (right). Source Google Earth.

Figure 1: Lake Urmia, December 1984 (left) and December 2020 (right). Source Google Earth.

 

The decline of saline lakes is a well-documented environmental tragedy. Iconic lakes like the Aral Sea, the Dead Sea, Urmia Lake and Utah’s Great Salt Lake are shrinking at alarming rates due to over-extraction of water for agriculture, industry, and urban use. As water levels drop, salinity increases, creating inhospitable conditions for many species. Exposed lakebeds become sources of toxic dust storms, harming human health and degrading surrounding landscapes.

 

The Expanding Lakes: A Lesser-Known Threat

While shrinking lakes dominate the headlines, some saline lakes are experiencing the opposite problem: rising water levels. For example, climate change can lead to more intense rainfall in certain regions, causing lakes to expand. Similarly, the melting of glaciers due to global warming can increase freshwater inflow into saline lakes. 

 

Figure 2: Tuosu Lake, December 1984 (left) and December 2020 (right). Source Google Earth.          Figure 2: Tuosu Lake, December 1984 (left) and December 2020 (right). Source Google Earth.

Figure 2: Tuosu Lake, December 1984 (left) and December 2020 (right). Source Google Earth. 

 

At first glance, rising water levels might seem beneficial, especially in the context of widespread drought and water scarcity. However, for saline lakes, this can be just as problematic as shrinking. Here’s why:

  • Decline in Salinity: Saline lakes are defined by their high salt content, which creates a unique habitat for specially adapted species. When water levels rise, the salt concentration decreases, disrupting the delicate balance of these ecosystems. Species that thrive in high-salinity environments may struggle to survive, leading to a loss of biodiversity.
  • Change in wetted period: Increased water inputs often arrive outside the season water would have naturally arrived and result in the lake having a shorter dry or hypersaline period than it naturally would have. Many of their unique plants and animals have special adaptations to the natural hydroperiod, which gives them a competitive advantage over invasive species.  
  • Flooding and Habitat Loss: Expanding lakes can flood surrounding areas, destroying terrestrial habitats and displacing wildlife. Here, Nature-based Solutions approaches like wetland restoration and the creation of buffer zones can be crucial for reducing flooding, protecting habitats, and enhancing biodiversity.
  • Altered Ecosystem Functions: Saline lakes play a critical role in nutrient cycling, carbon storage, and supporting migratory bird populations. Changes in water levels and salinity can disrupt these functions, with cascading effects on regional and global ecosystems.
  • Economic and Social Impacts: Many communities rely on saline lakes for tourism, fishing, and mineral extraction. Expanding lakes can disrupt these activities, leading to economic losses and social challenges. 

 

Toward Sustainable Solutions       

To protect saline lakes - whether shrinking or expanding - we must adopt holistic, nature-positive strategies. At the IUCN World Conservation Congress 2025, we’ll gather to explore and share the transformative power of Nature-based Solutions. Key steps include:

  • Integrated Water Management: Develop water management plans that balance human needs with ecosystem health.  
  • Climate Adaptation: Invest in climate resilience strategies to help ecosystems and communities adapt to changing water levels.  
  • Monitoring and Research: Improve monitoring of saline lakes to track changes in water levels, salinity, and biodiversity. Research can help us better understand the drivers of these changes and inform effective management strategies.
  • Community Involvement: Engage local communities in conservation efforts, ensuring that their knowledge and needs are incorporated into decision-making processes.
  • Global Cooperation: Many saline lakes span national borders, making international collaboration essential. Transboundary agreements and shared research initiatives can help address these challenges on a larger scale. 

 

A Call to Action

Join us at the International Society for Salt Lake Research proposed session at the IUCN World Conservation Congress 2025 in Abu Dhabi to discuss the conservation challenges of saline lakes and explore solutions for a sustainable, resilient future.  

The time to act is now. Share this message, engage in the conversation, and help protect our saline lakes—together, we can make a lasting difference.