(260324) -- ST. PETERSBURG, March 24, 2026 (Xinhua) -- A model of a vessel designed to handle oil spills is exhibited at the "Ecology of a Big City" international environmental forum in St. Petersburg, Russia, March 24, 2026. The forum kicked off here on Tuesday, attracting more than 6,000 participants. (Photo by Guo Feizhou/Xinhua)