Geog 1B

• Ecosystem 


  A system in which organisms interact with each other and their environment
• Abiotic 


  Non-living eg. air, water, heat, rocks
• Biotic 


  Living eg. plants, insects, animals etc
• Nutrient cycle

  Plants take in nutrients to build into new organic matter, which animals take in when eating plants. They are returned to the soil when animals die and the body is broken down by decomposers.
• Biomass


  The total mass of living organisms per unit area
• Biome 


  A large area of distinctive plant and animal groups which are adapted to that environment
• Tropical rainforest

  Along the equator

  Hot all year (25-30°C)

  High rainfall (over 200mm a year)
• Tropical rainforests are home to over half the worlds plants and animals
• Interdependence 


  Where plants and animals depend on each other for survival
• Rainforest Layers

  Emergent - Highest (reach 50m)

  Canopy - Most life is found (80%), 70% of sunlight

  Under Canopy - Trees that are 20m

  Forest Floor - Lowest layer w/ small trees adapted to shade
• Amazon : Location

  60% of the Amazon is in Brazil, an NEE in South America. Worlds largest tropical rainforest.
• UK Ecosystem : Hookstone Woods, Harrogate

  Lowland deciduous woodland (trees lose leaves)
• Why are there high rates of biodiversity?

  Warm + wet climate encourages a wide range of vegetation

  Fast recycling of nutrients

  Most of it is untouched
• Causes of deforestation: logging

  Timber harvested for commercial items eg. paper or furniture
• Causes of deforestation: agriculture

  Commercial farming accounts for 65-70% of deforestation Large scale ’slash and burn’ for ranches - increases carbon emission

  Soil erosion due to more exposed land
• Causes of deforestation: mineral extraction

  Precious metals found in rainforest

  Mined areas can experience soil and water contamination

  Displaces indigenous people for roads to transport products
• Causes of deforestation: tourism

  Mass tourism = building hotels in vulnerable areas = negative relationship between government + indigenous tribes

  Exposed animals to human diseases
• Causes of deforestation: energy

  High rainfall= ideal for hydro-electric power (HEP)

  HEP is the largest energy development in the Amazon, huge dams + reservoirs are built and forest is flooded
• Causes of deforestation: roads

  Roads built to provide access to mining areas, settlements and energy projects
• Impacts of deforestation: economic development

  + Mining, farming and logging= employment and tax

  + Products like meat provide income

  — Loss of biodiversity = reduced tourism
• Impacts of deforestation: soil erosion

  — when land is exposed from deforestation, soil is vulnerable to rain and with no roots to bind it, soil washes away
• Impacts of deforestation: climate change

  — Drier climate

  — Trees are carbon sinks and less of them means more greenhouse emissions in the atmosphere

  — Burning trees releases carbon dioxide
• Sustainable rainforest strategies

  Agro- forestry : growing trees + crops at the same time, prevents soil erosion and crops benefit from nutrients

  Selective logging : only trees of a certain height are cut

  Education : people understand consequences of deforestation

  Afforestation : if trees are cut, they’re replaced

  Forest reserves : areas that are protected from exploitation

  Eco tourism : tourism that promotes the environment and conservation
• Thar Desert : location

  Located on the border of India and Pakistan