THE ENVIRONMENT
and monitoring of the environment and in the enforcement of pollution control and environmental protection legislation. In 2000, a total of 308 430 tests on various. environmental matrices were conducted for monitoring the quality of the environment, representing a 10.3 per cent increase over that of the previous year. In addition, 1 606 tests were conducted for litigation purposes.
Technical support has been given to the Hong Kong Observatory's Environmental Radiation Monitoring Programme, to the Daya Bay Contingency Plan and to departments overseeing environmental impact assessment projects. The Laboratory also provided 24-hour on-site investigatory and advisory support services for the handling of emergencies involving spillage of chemicals or suspected emission of noxious and irritating gases.
The Laboratory continued to extend its analytical capabilities in the field of environmental analysis. This included the determination of ultra-trace levels of dioxins and related compounds using isotope dilution mass spectrometric techniques in various environmental matrices. Development work using non-destructive X-ray fluorescence techniques for elemental analysis was also undertaken to complement other adopted instrumental techniques involving the digestion or destruction of portions of samples.
Following the ISO14001 certification of the three environmental sections in 1999, the Laboratory has continued to implement the environmental management system so as to minimise the impact of its operation on the environment. Efforts were made to extend the certification to other sections in the Laboratory.
Flora
Hong Kong is near the northern limit of the distribution of tropical Asian flora and has an estimated 2900 species of vascular plants, both native and introduced. Various conservation measures have transformed the formerly bare hillsides and slopes into areas with trees of local and introduced species. Besides greening and beautifying the countryside, woodlands are important habitats for wildlife and are essential in protecting water catchments from soil erosion and in providing recreational opportunities for the public.
Remnants of the original forest cover, either scrub forest or well-developed woodlands, are still found in steep ravines. They have survived the destructive influences of man and hill fires through their location in precipitous topography and the moist winter micro-climate.
Terrestrial Fauna
Hong Kong's physical and climatic environment provides woody and grassy habitats for a wide variety of animals and plants. Under the pressures of urbanisation, larger animal species are rarely seen, but reptiles, amphibians, birds and insects are still
common.
The Mai Po Marshes form one of the most important wildlife conservation sites in Hong Kong. Together with the Inner Deep Bay area, the Mai Po Marshes were listed as a 'Wetland of International Importance Especially as Waterfowl Habitat' under the Ramsar Convention in September 1995. About 1 500 hectares of mudflats, fish ponds, marshes and dwarf mangroves provide a rich habitat for migratory and resident birds, particularly ducks and waders. Some 300 species of birds have
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