Modelling the Future of India's Keystone Desert Shrub

Haloxylon salicornicum might not be a household name, but this hardy shrub is the unsung hero of the Indian arid zone. Valued for stabilising sand dunes and providing livestock fodder, it is crucial for ecosystem restoration. However, its resilience in a warming world has remained poorly understood until now. A new study employs a sophisticated framework known as Ensemble Species Distribution Modelling (ESDM) to map the plant's future. By integrating seven machine learning algorithms with real-world occurrence records, researchers have created the first predictive map for this species.

To ensure the model reflected ecological reality, the team applied an Analytic Hierarchy Process. This method weighs non-climatic factors—such as soil type (edaphic factors) and urbanisation—alongside temperature and rainfall. Currently, the shrub thrives in about 12 to 15 per cent of the arid zone, particularly around Jaisalmer and Bikaner, favouring sandy soils and specific temperature bands.

The forecast for 2070 presents a stark divergent path. Under a high-emission scenario (RCP 8.5), the shrub’s climatically suitable habitat is projected to contract by 40 to 50 per cent. Conversely, a moderate scenario (RCP 4.5) suggests relative stability. The study reveals that while climate dictates where the shrub can grow, soil properties and human activity determine where it actually establishes. These findings identify persistent refugia in western Rajasthan as vital priority zones for future conservation efforts.