Listen to the South China Morning Post's podcast Speak Your Mind. This week our guest speakers are harbour and environmental activist Paul Zimmerman and student Carmen Chan. The stories on this page will help you stay ahead of the issues HOT ISSUES: Worsening air quality Public satisfaction with Hong Kong's environmental performance has fallen significantly because of concerns over air quality, according to poll results. This 'sadly telling' fact emerged during preparation of a 'sustainable development' index, in which respondents were asked to rate 10 aspects of life in the city. While the overall index declined only slightly, satisfaction with environmental protection fell from fifth place to ninth in interviews with 2,067 people aged 18 and over between October last year and February this year. The index, compiled by City University and the Canadian Chamber of Commerce, was 102.5, compared to 102.8 a year earlier and the 100 of the base year of 2003, reflecting a view that only little progress has been made on sustainable development. 'What's interesting and sadly telling, [is that] environmental protection has decreased in terms of people's happiness on how well the city performed,' said Anne Copeland Chiu, who was in charge of the study. About half the respondents believed clean air was the most important factor for higher satisfaction on the environment, followed by responsible waste management. More people also placed greater emphasis on reducing climate change, compared with last year. Former chief secretary Anson Chan Fang On-sang, the 'ambassador' of the index, said the government, business and public should work together to improve the environment. 'It is clear from this year's index that the area of greatest public disappointment is our worsening air quality,' she said. 'This is adversely affecting Hong Kong's attractiveness as a place in which to live and do business.' Cheung Chi-fai, South China Morning Post, June 17 Mainland initiative Guangdong factories may have to bid for 'rights to pollute' from the central government under an initiative to encourage polluters to minimise emission and effluent, mainland officials said. The plan, expected to be introduced gradually this year, will pave the way for trading on air emissions and waste-water discharges. The Guangdong provincial finance bureau's deputy chief, Zheng Zhiquan, said the move was aimed at reflecting the environmental costs in production. 'The government will transfer emission rights to polluters at a price through tender, auction or other means,' Mr Zheng said. 'Big polluters will be given fixed emission quotas and those having surplus quotas can sell them to those in deficit.' Earlier, the State Council assigned emission and effluent quotas to individual provinces. Guangdong has to lower its sulfur dioxide emission from 1.29 million tonnes last year to 1.1 million tonnes by 2010, when it also has to meet targets agreed with Hong Kong. Leu Siew Ying and Cheung Chi-fai, the Post, June 16 Cutting vehicle emissions The environment minister is studying the possibility of expediting the phasing out of vehicles with outdated emission standards in an attempt to reduce air pollution. The measure is among several options being reviewed by the Council for Sustainable Development. Another possibility would see a switch to cleaner fuel for local ferries, and for industrial and construction purposes. Secretary for the Environment, Transport and Works Sarah Liao Sau-tung said officials were studying the cost and benefits of phasing out old vehicles. Although Hong Kong is closely following the European Union's new vehicle and emission standards, such as the adoption of the Euro IV standard this year, thousands of vehicles of lower standards remain on the streets as Euro IV only applies to new cars. 'We are studying how many old vehicles there are and what we can do to accelerate the rate of phasing them out,' Dr Liao said. 'We'll look at how much effect they will bring, say if we turn all the cars into Euro IV. What if we have to pay several billion dollars only to achieve a 0.1 per cent reduction. Is that worth doing?' Dr Liao said that if the government did decide to dispose of old vehicles, it was not likely to pay the full cost of each replacement. Instead, financial subsidies might be considered. Dr Liao agreed Hong Kong had to deal with its own pollution, on top of any regional efforts to tackle the smog. However, she said it was never easy to strike a balance between better air quality and the cost to society. As an example, she cited stricter ferry and cross-border truck emission controls that might lead to fare rises and increases in operating costs. Cheung Chi-fai, the Post, June 5 SPEAK YOUR MIND GUESTS Paul Zimmerman convenor of the group Designing Hong Kong Harbour District Carmen Chan, 13 Year 8 student at South Island school. She is passionate about the environment, and is willing to do what she can to protect it. She has sent two letters, one personal and one on behalf of her class, to Chief Executive Donald Tsang Yam-kuen, urging him to do what he can to clean up Hong Kong's polluted air SPEAK YOUR MIND HOSTS Luisa Tam Opinion Pages editor Alex Lo columnist