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The Environment

extraordinary composition, the columns are considered unique for their size, with an average diameter of 1.2 metres, and the large area they cover, of more than 100 sq km.

The Hong Kong Geological Survey under the Civil Engineering and Development Department produces a series of fifteen 1:20,000-scale geological maps and six accompanying geological memoirs. It also publishes two summary memoirs and a set of 1:100,000-scale geological and thematic maps in Chinese and English, synthesising and giving a popular account of local geology. The department provides geological information on its website.

Flora

Hong Kong is situated near the northern boundary of the distribution of tropical Southeast Asian flora, sharing similar species and structure with the flora of Guangdong. Despite its small size, Hong Kong has a rich flora with about 3,300 species of vascular plants, of which 2,100 are native to the territory.

The major types of vegetation cover comprise woodland, shrubland and grassland. Remnants of the original forest cover can still be found in steep ravines or behind traditional villages in rural areas. They have survived as a result of their location in precipitous topography and the moist micro-climate, or because they are protected for cultural reasons.

Continual afforestation efforts coupled with conservation measures have transformed formerly bare hillsides and slopes into impressive woodlands. Besides greening and beautifying the countryside, woodlands are important habitats for wildlife and are essential to protect water catchments from soil erosion.

Fauna

Terrestrial

The climate and physical environment provide a wide range of habitats and support for a rich and varied fauna that includes over 540 species of birds, 57 species of terrestrial mammals, 24 species of amphibians, 86 species of reptiles, 198 species of freshwater fish, 236 species of butterflies and 123 species of dragonflies.

Besides the rich terrestrial fauna biodiversity, a number of species are endemic to Hong Kong, including the Romer's Tree Frog, Bogadek's Burrowing Lizard, Hong Kong Tusktail and Hong Kong Clubtail. Newly recorded species are discovered from time to time. Globally endangered or threatened species, such as the Three-banded Box Turtle, Yellow-breasted Bunting, Short- legged Toad, Green Turtle and Chinese Pangolin, can also be found.

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 area is listed as a 'Wetland of International Importance' under the Ramsar Convention. About 1,500 hectares of inter-tidal mudflats, fish ponds, marshes, reedbeds and mangroves provide a rich habitat for migratory and resident birds, particularly waterbirds. More than 390 species of birds have been observed in this area. Forty-nine species are considered globally threatened, including the Black-faced Spoonbill, Baer's Pochard, Nordmann's Greenshank and Spoon-billed Sandpiper. The Agriculture,

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