Hong Kong forests Flashcards
Woodland accounts for how many % of Hong Kong area?
24.9%
Vegetated area covers about how many % of Hong Kong land area?
78.7%
What is ecological succession?
Process of change in species that make up an ecological community over time
What is primary succession?
Begins in new habitats and uninfluenced by pre-existing communities
What is secondary succession?
Succession follows by disturbance of pre-existing community
What are the causes of ecological succession?
Natural forest fires, pests, natural hazards, human disturbances (clear-cutting, fire, roads)
What are grassland?
Vegetation principally make up of grass and graminoid (類禾本植物) with less than 1% of shrub per unit area
What are the two types of grassland in Hong Kong?
Hill Grassland, old field grassland
What is the characteristics of old-field grassland?
Hard soil, presence of hardpan retards secondary succession (shrubs are hard to grow)
Where can we find the hill grassland?
Exposed steep site above 300m, e.g. Tai Mo Shan, Ma On Shan
What is a plagioclimax community?
habitat in which the influences of the humans have prevented the ecosystem from reaching the climax community
Why grasses can survive in harsh environment?
Extensive root system requires shallow soils to ancourage; growth tissues are protected under soil (geophytes/ hemi cryptophytes)
How long does it take to turn grassland to shrubland w/o human disturbances ?
10-15 years
What are the characteristics of shrubland?
Few grasses; Evergreen shrubs, presence of birds and smalls mammals
What are the characteristics of forest?
> 3m and thick canopy
