Chief Executive Donald Tsang Yam-kuen should address the tough issues in resolving air pollution rather than just shopping for the easiest means to tackle the problems, the Conservancy Association said yesterday. Releasing its 10 recommendations to improve air quality, which the association wants Mr Tsang to incorporate in next Wednesday's policy address, the group said it was time for Mr Tsang to show strong governance. If the government had the political will and was really strong in governance it would face no hurdles, association chairwoman Betty Ho Siu-fong said. Ms Ho said the most difficult of their recommendations were those that might involve the mainland, as these were beyond Hong Kong's control. She added that solutions that required the public or businesses to pay could be justified by their benefits. The group suggested legally requiring local industries to switch to using ultra-low sulfur diesel fuel and urging bus companies to gradually replace their fleets with the latest environmentally-friendly vehicles. It also called for the government to turn its fleet of saloon cars into hybrid cars within five years and for a plastic bags tax to be introduced immediately.