GQ 1: What are Tropical Rainforests?

Characteristics of Tropical Rainforests
1. Diversity of Plant Species
  1. Variety of plants and animals. Large Biodiversity. 0.01 km contains about 300 different species of animals
2. Structure of the tropical rainforest
  1. Emergent Layer
    1. From 50m to 80m. Trees rise above the canopy layer
    2. Formed by the crown of trees. Very tall and straight with smooth trunks
    3. Examples: Tualang Tree and Kapok Tree
  2. Canopy Layer
    1. 20m to 50m. Crowns of trees grow in a continuous canopy layer like and umbrella blocking 90% of sunlight
    2. Lianas and Epiphytes can be found in this layer. They grow to get as much sunlight as it can.
  3. Undergrowth Layer
    1. 20m and below. It is generally darker because sun's rays are blocked by the canopy. Plants have larger leaves to capture sunlight
    2. Plants widely spaced and sparse due to lack on sunlight. Forest floor hot and wet encouraging decomposition leaving layer of leaf litter
3. Adaptation of Plants
  1. Bark and Branches
    1. Tall and straight trunks with branches near top of trees. Helps trees get most sunlight
    2. Smooth bark allows rainwater to flow easily from crown to roots of trees
  2. Leaves
    1. Broad leaves to capture sunlight
    2. Waxy, Hairy and leathery surface to minimise loss of moisture through transpiration
    3. Drip tips to allow water to run off easily. This is to prevent fungal growth on leaves
  3. Fruits and Flowers
    1. Fruits and flowers are bright and colourful and strong smelling. This attracts insects and other animals for dispersal of seeds or pollination
  4. Roots
    1. Buttress roots: Large roots that grow 1 to 5 m above ground. This is to support the heavy weight of trees which are very tall
    2. Roots are shallow as nutrients are mostly in the top layer of soil
    3. Water available throughout the year, so no need for deep roots
Uses of Tropical Rainforests
1. Water Catchment
  1. Refers to an area drained by a river and the smaller rivers that flow into it
  2. Water drips from trees and seeps into the ground. This is stored as groundwater
  3. Impurities in the water is trapped by the soil before it flows into the reservoir
  4. Example: Central Catchment Nature Reserve Singapore
2. Green Lungs of the Earth
  1. Trees in the forests absorb carbon dioxide from atmosphere and release oxygen through the process of photosynthesis
  2. Trees also act as the earth's natural air purifier as they absorb tonnes of CO2 every year
  3. Dense vegetation also keeps the earth cool!
3. Habitat to Flora and Fauna
  1. Home to more than 2 million species which represents over half of the world's species of flora and fauna
  2. Ample sunlight allows plants to convert it into energy and food. Animals will in turn eat the food provided.
  3. Canopy is a habitat where other plants can grow and animals can live.
  4. Examples: Trilobite Beetle, Macaque
4. Habitat to Indigenous people
  1. Many indigenous people live in Rainforests for thousands of years. It provides them with basic necessities such as food and water
  2. Known as hunter gatherers, they gather and grow food that is only just enough for their needs
  3. Shifting cultivators grow their own plants and medicine by burning vegetation to provide nutrients for soil.
  4. Example - Penan of Sarawak
5. Source of timber
  1. Forests trees can be cut down as timber. This can be made into furniture and other uses
  2. Examples: Meranti, Teak wood, Mahogany
6. Medical Application
  1. Rainforests contain plants that can contain medicinal properties and cures for diseases. 3000 plants have been identified in the Amazon Rainforest
  2. Example: Cinchona Tree used to treat malaria. Madagascar Periwinkle trests childhood leukemia

Next up

GQ 1: What are Tropical Rainforests?

Description

Resource summary

Similar

	Created by Wak Fairus about 10 years ago