Acid deposition poses a significant threat to stone sculptures in urban environments, accelerating erosion and chemical weathering. To safeguard these cultural treasures, implementing proactive protection strategies is essential.

1. Regular Cleaning: Gently wash sculptures with pH-neutral water to remove acidic pollutants before they cause irreversible damage. Avoid abrasive techniques that could scratch the surface.

2. Protective Coatings: Apply breathable, water-repellent coatings like siloxane or fluoropolymer-based products. These create a protective barrier while allowing the stone to "breathe," preventing moisture buildup.

3. Shelter Solutions: Where possible, install protective canopies or relocate vulnerable sculptures to sheltered areas. This reduces direct exposure to acid rain and airborne pollutants.

4. Material Selection: For new installations, choose acid-resistant stones like granite or quartzite in high-pollution areas. These naturally withstand acidic conditions better than limestone or marble.

5. Environmental Monitoring: Install sensors to track air quality and moisture levels near sculptures. This data helps determine when protective measures should be intensified.

6. Professional Maintenance: Schedule annual inspections by conservation specialists who can identify early signs of acid damage and recommend appropriate treatments.

7. Urban Planning: Advocate for green buffers around sculpture sites. Vegetation helps filter pollutants and reduces acid deposition impact.

By combining these approaches, urban planners and conservators can significantly extend the lifespan of stone sculptures while maintaining their aesthetic and historical value in challenging environments. Regular maintenance and adaptive strategies remain key to combating the persistent threat of acid deposition.