によって Wang ShiMei 12年前.
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Chapter 3, Natural vegetation
Natural vegetation comprises diverse ecosystems, such as coniferous forests, mangrove forests, and tropical rainforests, each with unique characteristics. Coniferous forests, featuring species like pine and spruce, typically have needle-like evergreen leaves and thrive in cold climates, particularly in regions like Alaska and Northern Canada.
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Chapter 3, Natural vegetation Coniferous Forests Roots Shallow spreading roots Branches slope downwards Thick bark Male cones produce pollens Female cones produce seeds Needle-like Not dense Pure stands of single species such as pine and spruce Uniform in height 300mm to 635mm in rainfall As low as -40degree in winter, about 21degree in the summer Mainly located in Alaska, Northern Canada. Areas of high altitudes where the climate is cold Between 60N and 70N of the equator Tropical Monsoon Forests Deep tap roots Branches are around the middle Thick and coarse bark Flowering and fruiting during the dry season Waxy with drip tips Decidous Dense undergrowth Dense during wet season, sparse during dry season High biodiversity but fewer than tropical rainforests 3 vertical layers (Canopy layer, Understorey layer, Undergrowth) Over 1500mm, with wet and dry seasons About 26degree Southeast Asia, Southern China and Northern Australia Between 10 and 25 N and S of the equator Mangrove Forests Aerial, Prop and Kneed roots Bark and Branches No adaptation to climate or environment Buoyant fruits with sharp tips Broad, leathery with drip tips Dense canopy 4 main species: Avicennia, Sonneratia, Rhizophora, Bruguiera 3 horizontal zones (coastal zone, middle zone, inland zone) Climate (temperature and rainfall) 1000mm to 2000mm in rainfall 20 to 30degree Can be found in especially along sheltered coastal regions and places where rivers constantly deposit clay and silt. Between 23.5N and S of the equator Tropical Rainforests Roots Shallow buttress roots Bark and branches Smooth and thin bark Branches are high up on the trunk Flowers and fruits Colourful flowers Flowering and fruiting all year round Leaves Broad, waxy and drip tips Evergreen Density Sparse undergrowth Dense emergent and canopy layers Diversity of plants High biodiversity Structure 5 vertical layers(Emergent layer, Canopy layer, Understorey layer, Shrub layer, Undergrowth layer) Climate(temperature and rainfall) Over 1500mm in rainfall About 27degree Distribution Eg. Amazon Basin in South America and Congo Basin in Africa Between 10N and S of the equator