Jaipur, June 5 -- Rampant illegal mining and encroachments have caused Rajasthan's Sambhar Lake to shrink by about 90% in five decades, a study by the Central University of Rajasthan has revealed. The research carried out by professor Laxmi Kant Sharma and his team at the Environment Sciences Department shows that the wetland area of Sambhar Lake declined from 159.6 square km in 1972 to 17.4 square km in 2019, representing an 89% reduction in wetland extent. The lake itself could lose its wetland character by 2059 if rampant illegal encroachment and construction in the lake bed continues, the study projects. Published in 2021 in PLOS ONE, the study used historical CORONA satellite imagery, field observations and predictive modelling to track changes in the lake ecosystem from 1963 and project future trends to 2059. The analysis found that as the wetland area declined dramatically, saline soils, barren land, illegal salt pans and human settlements expanded across the lake basin. Prof. Sharma said, "The greatest threat to the lake is illegal encroachment in the core area. Many illegal tubewells have been drilled and long pumps have been used to extract ground water." Sambhar Lake is the largest inland saline wetland of India. It was designated a Ramsar site on March 23, 1990 and as a Key Biodiversity Area in 2004. The wetland is a vital wintering habitat for thousands of migratory flamingos and waterfowl that travel thousands of kilometres. The lake has significant economic value, with government and private operators producing about 210,000 metric tonnes of salt annually, across government and private sectors. A 2025 study by Sharma's team, published in Science of the Total Environment, highlighted the role of inland wetlands such as Sambhar Lake as carbon sinks. The study describes carbon stored in freshwater and saline wetlands as "teal carbon", a concept referring to the carbon sequestration potential of inland wetland ecosystems. The National Green Tribunal (NGT) has issued multiple directives to the state government to protect the fragile ecology of Sambhar Lake. Through its orders, the NGT has directed cancellation of illegal salt pans in the designated wetland area, regulation of tourism activities that could disrupt migratory birds, and strict ecological monitoring. But the wetland continues to face threats. Illegal salt pans and deep tube wells have encroached upon the lake bed, depleting brine reserves, altering salinity and reducing water availability before the winter migration season. Om Prakash Sharma of Gram Chetna Kendra, an NGO based in Sambhar said illegal salt extraction continues despite regulatory efforts. He added that salt workers often suffer from skin ailments, fluoride-related health problems and seasonal livelihood insecurity. Increasing infrastructure developments such as solar power plants, a railway line, and unregulated tourism activity also threaten the fragile ecosystem. Untreated water from Sambhar town flows into the lake, further causing pollution. Deputy conservator of forests, Jaipur, Ketan Kumar said the state wetland authority has issued directions to district authorities to crackdown on illegal activities. "We hold regular meetings with Jaipur, Nagaur and Ajmer district authorities and with the revenue department, police, electricity department and district collectors. The lake comes under the revenue department and the departments and local authorities have been asked to take steps to stop illegal mining activities," he said....