當年今日﹕World Wetlands Day
【明報專訊】Between the lush grasslands and oceans that sparkle in the sun, nature has bestowed on us the richness and diversity of wetlands. Today is World Wetlands Day, which marks the adoption of the Ramsar Convention (《拉姆薩爾公約》).
1. What are wetlands?
As defined in the Ramsar Convention, wetlands are "areas of marsh, fen, peatland or water, whether natural or artificial, permanent or temporary, with water that is static (靜止的) or flowing, fresh, brackish (鹹的) or salt (含鹽的), including areas of marine water the depth of which at low tide does not exceed six metres".
Examples of wetlands include marshes (沼澤) and ponds, the edge of a lake or ocean, the delta (三角洲) at the mouth of a river and low-lying areas that frequently flood. They are found on every continent except Antarctica. Wetlands vary widely because of differences in soils, topography(地形), climate, hydrology (水文學), water chemistry, vegetation and other factors. Wetlands may be filled mostly with trees, grasses, shrubs (灌木叢) or moss (苔蘚).
2. Value of wetlands
Wetlands are of great ecological (生態的) value as they are considered the most biologically diverse of all ecosystems (生態系統). They serve as home to a wide range of plants and animals. They are the habitats of, as well as nurseries for, a melange (大雜燴) of species including mammals, birds, fishes and invertebrates (無脊椎動物). Wetlands also support the cultivation of rice.
Wetlands are also important for their functions of water filtration (by virtue of which they are also known as "kidneys for other ecosystems"), storm protection, flood control and recreation.
3. Threat to wetlands
Owing to their abundance (充裕) of fish, fuel and water, wetlands are vulnerable to over-exploitation (過度開發), and are targeted for drainage or conversion when they are viewed as unproductive or marginal lands. This gives rise to the need to protect wetlands through international cooperation.
4. The Ramsar Convention
Adopted on 2 February 1971, in an Iranian city Ramsar, the Ramsar Convention "provides the framework for national action and international cooperation for the conservation and wise use of wetlands and their resources". The List of Wetlands of International Importance (also called the Ramsar List), a key component of the treaty, has so far designated more than 2,000 sites, which altogether encompass more than 200 million hectares. These sites are recognised because they are of significant value not only to the country or the countries in which they are located but also to humanity as a whole.
So far the Ramsar Convention has protected more than 476,000 acres of wetland, saving them and their services for future generations.
5. Hong Kong Wetland Park
Hong Kong Wetland Park, our city's answer to the international effort to protect wetlands, is a conservation, education and tourism facility in the northern part of Tin Shui Wai. It opened to the public on 20 May 2006, and now comprises a 10,000-square-metre visitor centre, Wetland Interactive World, and a 60-hectare Wetland Reserve. The park has attracted more than 460,000 visitors, including over 63,000 tourists from other parts of the world.
