THE ENVIRONMENT
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streams, and
and open
hillsides. Some 20 freshwater reservoirs of various sizes nestle among the hills, giving additional charm to the scenery.
About 75 per cent of Hong Kong's land area consists of hills and the vegetation on them includes grass, scrub, and some 125 square kilometres of woodland - much of it the result of afforestation programmes. The woodlands not only make the countryside more beautiful but are important in the management of water catchments.
The Agriculture and Fisheries Department is the principal government agency responsible for conserving the territory's countryside. The Country Parks Ordinance, which came into effect in early 1976, provides for the designation, control and management of the most important areas of countryside as country parks, and enables them to be developed for recreational purposes. It also gives particular protection to vegetation and wildlife. There are now 21 country parks throughout Hong Kong, covering about, 40 per cent of the land area.
Within these country parks, recreational amenities include picnic and barbecue places, waymarked walks, shelters, toilets, and information and educational services. Road access is also being improved to enable park staff to deal more effectively with fires and litter - the most serious problems created by visitors.
The department also has the responsibility for protecting the flora and fauna throughout the whole of Hong Kong. The Forests and Countryside Ordinance provides for the general protection and management of vegetation, and special protection is given to certain plants including native camelias, magnolias, orchids, azaleas and the Chinese New Year Flower. The Wild Animals Protection Ordinance prohibits hunting of wild animals and restricts the entry of unauthorised members of the public into two important wildlife habitats, the Mai Po Marshes and the Yim Tso Ha Egretry.
Overall enforcement of the ordinances is carried out by park rangers, park wardens and nature wardens. These officers also provide information at visitor centres and at ranger posts and escort groups on guided visits.
In addition to general conservation of the countryside, Hong Kong has now adopted the concept of identifying and conserving sites of special scientific interest to ecologists, such as a site where a rare tree or a rare species of butterfly can be found. More than 40 sites have been identified for future conservation action.
Topography and Geology
Hong Kong is part of an ancient Cathaysian landmass that some 1 000 million years ago extended from Shandong (Shantung) in northern China to the Gulf of Hainan. Following intensive folding of its metamorphic and crystalline rocks, intense mountain-building occurred with granitic and volcanic intrusions during the Mesozoic period, about 250 million years ago. From the beginning of the Quaternary period, between two to three million years ago, the lower-lying areas were alternately flooded or exposed as masses of water were locked up or released from ice sheets. The last marine incursion was about 10 000 years ago; since that time there have been sporadic depositions of sedimentary material eroded from the hills.
This erosion of the hills and deposition in the valleys increased rapidly following the widespread colonisation of the Hong Kong area during the Song Dynasty (960–1279).
Large volumes of sedimentary material are brought regularly to Hong Kong by the Zhu Jiang (Pearl) River, but this process has been accelerated in recent years by extensive reclamation projects along the coastline. Hong Kong's granitic and volcanic rocks are deeply weathered and are prone to landslides if disturbed, but they can be excavated quite