Mai Po Logo: Pied Kingfisher |
|
 |
A combination of historical records and a recent systematic vascular plant survey at Mai Po show around 250 species to be distributed across the Reserve. These are classified into 6 main groups: ferns, herbs, grass and sedges, climbers, shrubs and trees. Around 30% of them are exotic species.
| |
.jpg)
© Maja Willis |
|
Ferns are a group of primitive non-flowering vascular plants which reproduce only by spores. Twelve native species are known from Mai Po and are found in shady humid environments typically beside footpaths or underneath trees. The Mangrove Fern Acrostichum aureum, as its name suggests, is a specialist of mangrove areas and is commonly seen inside the Mai Po gei wai and intertidal mangrove forest.
Herbs are the largest vascular plant group at Mai Po. Over sixty-five species have been recorded. Terrestrial species occupy bund and path areas, but the margins and centralized areas of gei wai/pond are home to the both aquatic and semi-aquatic species. Generally only a few herbs grow in the intertidal areas due to the unstable substratum, moving water and salinity levels. Flowering herbs attract insects which in turn are food for birds and other wildlife. Several herbs are also directly consumed by waterbirds, for example, Lesser Duck-weed Lemna minor is fodder for wintering ducks.
Around 45 species of grasses and sedges occur in Mai Po with 80% of them being native. They are a gregarious plant group found growing extensively on dry land, in water depths up to 1m and in both freshwater and brackish water areas. A variety of wildlife depends upon them for food and for roosting inside. A good example is the large stands of Reed Grass Phragmites australis in Mai Po which support more than 400 invertebrate species and over 40 species of birds.
There are over 55 species of shrubs, over 45 species of trees and 20 climber species in Mai Po. Among the shrub and tree species in Mai Po, the most extensive is mangrove; a group of plants highly adapted to inter-tidal conditions. Seven of the 8 Hong Kong true mangrove species occur at Mai Po with most growing inside the 115ha mangrove stand in the inter-tidal zone. This is the largest stand in Hong Kong. If left unmanaged climbers are a threat to the health of many mangrove stands because they block sunlight, but they do produce nectar for insects. Other species of shrubs and trees grow naturally on the gei wai bunds including Elephant’s Ear Macaranga tanarius and Cuban Bast Hibiscus tiliaceus, but some are deliberately planted to either provide food and nectar for wildlife or act as barriers to reduce human disturbance to birds. |
