香港的生物多样性及其保育工作

The present status and conservation of the biodiversity in Hon g Kong

香港位于热带，属海洋性气候。地势崎岖多山，山地约占全港总面积的3/4。城市发展多集中在沿海平坦地带。目前香港的城市和乡镇面积约占总面积的20%，农地约占5%(当中大部份已遭荒废)，余下的均为郊野地区，这包括天然林和人工林(约占14%)、灌丛(约占36%)及草地(约占17%)。由于良好的气候和地理条件，形成了众多不同的生态环境，使总面积仅1090 km2的弹丸之地孕育出种类多样的动植物，生物多样性十分丰富。香港约有2500种原生植物，包括被子植物约1900种，裸子植物7种，蕨类植物220多种及苔藓植物300多种。动物方面，已记录的野生哺乳类动物有40多种，鸟类超过459种，两栖类23种，爬行类70多种。昆虫种类繁多，其中蜻蜓目100多种，鳞翅目2200多种(蝴蝶200多种，蛾类2000多种)。有很多是国家保护物种和特有种。植物方面属国家一级保护的有1种——刺桫椤(Alsophila spinulosa)；国家二级保护的有6种，如四药门花(Tetrathryrium subcordatum)；国家三级保护的有8种，如穗花杉(Amentotaxus argotaenia)。此外，香港特有种有16种，例如紫萁科(Osmundaceae)的粤紫萁(Osmunda mildei)、马兜铃科(Aristolochiaceae)的香港细辛(Asarum hongkongense)和兰科(Orchidaceae)的谢氏卷瓣兰(Bulbophyllum

The Hong Kong Special Administrative Region lies within the tropics and experien ces a maritime climate. As a part of the Guangdong coastal massif, it is charac terized by a hilly terrain. The highest peak is Damaoshan Mountain(957 m) and h illy areas (altitudes above 150 m) account for three quarters of the total land area. Due to the general lack of flat land, urban development is concentrated a long coastal areas. The developed areas (including urban areas and rural towns ) account for about 20% of the total land area, agricultural land about 5% (most of which is abandoned), and the rest is countryside including native woodlands and plantations (15%), shrublands (36%) and grasslands (17%). The favourable climate and geographical conditions bring about a large variety o f ecological environments, which in turn support an exuberant variety of both pl ants and animals making Hong Kong, such a small place of 1090 km2, very rich i n biological diversity. There are about 2500 species of native plants, includin g 1900 species of angiosperms, seven species of gymnosperms, around 220 species of ferns and about 300 species of bryophytes. For wild fauna, so far about 40 s pecies of wild mammals, more than 459 species of birds, 23 species of amphibians , around 70 species of reptiles, about 100 species of dragonflies, about 220 spe cies of butterflies and 2000 species of moths have been recorded. As well as ha ving a huge variety, some of these species are protected by China's government a nd others are endemic. For plants, there is one species (Spiny Tree Fern, Alsophila spinulosa) listed in Category I of the State Protection List, three species (e.g. Tetrathryrium subcordatum ) in Category II and eight species (e.g. Amentotaxus argotaenia) in Category III. Moreover, there are 16 endemic plant species in Hong Kong. Examp les are Osmunda mildei (Osmundaceae), Asarum hongkongense (Aristolochiac eae) and Bulbophyllum tseanum (Orchidaceae). For animals, there are n ine species listed in Category I of the State Protection List (e.g. the Chinese White Dolphin, Sousa chinensis), and 79 species in Category II. Endemic animals include Romer's Tree Frog (Philautus romeri), Bogadek's Leg less Lizard (Dibamus bogadeki) and many insects. To protect the varieties of wild animals, plants and their habitats, the Hong Ko ng SAR Government has formulated some ordinances and launched quite a few conser vation measures. For instance, there are 21 country parks and 14 special areas, covering about 38% of the total land area of Hong Kong. There are also two spe cial restricted zones, three marine parks, and one marine reserve. The governme nt has also set up 59 'Site of Special Scientific Interest' (SSSI) so as to cons erve and study various species of plants and animals, ecosystem, special geology and landscapes in Hong Kong. Having a population of over six million in such a small territory, Hong Kong is one of the most populated places in the world. Its biological treasure has bee n threatened by human activities for centuries. Drastic population growth in re cent years has led to more developments in the countryside, which has destroyed natural habitats and brought more severe pollution problems. Many wild plants h ave been overexploited for their medicinal, ornamental or other values. All t he above has seriously harmed wild plants, animals and their habitats, some of w hich are now close to extinction. It is high time to conserve biodiversity and develop a comprehensive strategy. The Department of Ecology and Biodiversity of the University of Hong Kong commenced a 3year 'Hong Kong Biodiversity Study' in 1996. Its aim is to increase our understanding of the current status of native flora and fauna, and to suggest proposals to conserve the rare and endangered sp ecies and restore the deteriorating natural environment and to lay a foundation to devise long_term conservation strategies for Hong Kong SAR.