Tropical Rainforests

• where are tropical rainforests found?

  between the Tropics in Central and South America and South East Asia.
• what is the climate of tropical rainforests?

  high rainfall of over 200mm. constant temperatures of 27C. a 6 month period of intense rainfall from October-May.
• what is soil like in tropical rainforests?

  infertile with high iron content and nutrient cycling.
• what plants and animals are there ?

  they have huge biodiversity. birds leave in the canopies, mammals like monkeys live in the trees, deers and rodents live on the forest floor.
• how have plants adapted?


  there are la
• what is leaching?

  heavy rainfall which dissolves and carries nutrients leaving behind red latosol.
• what are the layers in the rainforest?

  emergent

  top canopy (30-60m)

  canopy (15-30m)

  lower canopy (5-15m)

  shrub layer/ground layer (5m)

  soil
• what happens in the top canopy/emergents?

  fast growing trees compete for sunlight. leaves are flexible and turn to the sun. drip tips are here as well.
• what happens in the middle canopy?

  epiphytes
• what is in the lower canopy?

  Lianas
• what happens in the shrub layer/ground layer ?

  there is thin smooth bark with buttress roots
• what are drip tips?

  excess water allows the water to run off the leaves.
• what is an example of an emergent?

  Capoc trees.
• what are epiphytes?

  plants growing on branches high in the company to seek sunlight and obtain nutrients from the water and air.
• what is thin smooth bark?

  the water flows down easily to the soil.
• what are leaves with flexible bases?

  they turn to the sun.
• what are buttress roots?

  massive ridges support the base of tall trees and transport water. increases carbon/oxygen gas exchange as they increase surface area.
• what are lianas?

  woody climbing vines that have roots in the soil but are carried by trees into the canopy.
• what are animal adaptations ?

  1) animals have developed poison

  
  

  2) snakes and frogs can paralyse and kill other animals when threatened.

  
  

  3) living in trees helps find food.

  
  

  4) the spider monkey has long limbs to help it swing.

  
  

  5) animals can camouflage such as leaf tailed geckos.

  
  

  6) jaguars in tropical rainforests are smaller so they can move through dense vegetation.
• explain the interdependence in the rainforest.

  intense rainfall -> more leaching -> they grow shallow roots to optimize nutrients uptake
• what is deforestation?

  the action of clearing a wide area of trees.
• what are the causes of deforestation?

  subsistence and commercial farming, logging, road building, mineral extraction, energy development, settlement, population growth
• what is the rate of deforestation?

  since 2004 it has fallen by 80% in Brazil due to consumer pressure and environmental targets.
• what are the impacts of deforestation?

  Economic development, soil erosion and contribution to climate change
• why are tropical rainforests important?

  provide natural resources and around 25% of medicines. absorbs 5% of global CO2 emissions with huge biodiversity and provides fresh water from the Amazon Basin.
• how can rainforests be sustainably managed?

  selective logging, replanting, ecotourism, international hardwood agreements, education, reducing debt, conservation
• what is the difference betwen subsistence and commercial farming?

  subsistence only benefits the farmer but commercial is for profit. land is burnt to make space for cattle ranching for beef.
• how does road building cause deforestation?

  Trees are cleared to provide access to more areas and to bring machinery for mining/construction, the BR163 is an example for Brazil. Animals are killed and chemicals damage the environment.
• how does mineral extraction cause deforestation?

  drilling and mining for tin and gold leaves vast areas barrren for hundreds of years.
• how does population growth cause deforestation?

  people from overpopulated areas moved into rainforests. many plantations were set up to provide job opportunities. they were not educated on sustainability so the area was cleared harshly.
• what is the impact of deforestation on economic development?

  lose resources but gain enegy in the form of hydroelectric power, as dams are built but this completely destroys habitats.
• what is the impact of deforestation on soil erosion?

  removal of the topsoil which is the most fertile part is being eroded faster than it is replaced due to activity from humans/animals and also natural activity from the water/wind. Barren land leaves it more exposed.
• what is the impact of deforestation on climate change?

  carbon sinks are lost so more greenhouse gas is released.
• what is the difference between logging and selective logging and replanting?

  cuting down trees and transporting the logs to sawmills. clear cutting is when all the trees in an area are cut down. selective logging is when only mature trees are cut down. and they are cut to fall away from other trees. replanting prevents soil erosion and promotes CO2 intake.
• what is conservation and education?

  legally enforces protection. national parks and nature reserves are undisturbed. educating companies and consumers of products produced in rainforests reduces the demand and encourages sustainable practices.
• what is ecotourism?

  sustainable tourism which supports conservation. as more people want to visit the rainforest, ecotourism becomes more popular. it includes approaching activities in a sustainable way. Ecotourism helps indigenous people.
• how are international agreements useful?

  debt for nature swaps, a country cancels debt owed if the country conserves and protects their environment. the 2006 International Tropical Timber Agreement, develops sustainable hardwood for trade.
• how is the use of tropical hardwood sustainable?

  tropical hardwood is in high demand so international agreements promotes sustainable supply for hardwood.
• how is debt reduction useuful?

  debt is paid by richer countries and is offered to less developed countries. the developing country has to conserve parts of their environment in return.