UNIT 5 — Land & Water Use

Agriculture

Green Revolution

• High-yield crops
  
  

• Fertilizers
  
  

• Irrigation
  
  

• Pesticides
  
  Pros: more food
  
  Cons: pollution, soil degradation
  
  

Irrigation

• Problems
  
  

  • salinization
    
    

  • waterlogging
    
    

  • groundwater depletion
    
    

• Best method: Drip irrigation
  
  

Fertilizers & Eutrophication

• Nitrogen + Phosphorus runoff
  
  

• Algae bloom
  
  

• Blocks sunlight
  
  

• Plants die
  
  

• Decomposition uses oxygen
  
  

• Creates hypoxic dead zone
  
  

Pesticides

• Can cause resistance
  
  

• Bioaccumulation
  
  

• Biomagnification
  
  

• IPM (Integrated Pest Management) = BEST SOLUTION
  
  

  • biological control
    
    

  • minimal chemical use
    
    

  • crop rotation
    
    

Food Production Types

• CAFOs
  
  

  • cheap meat
    
    

  • pollution
    
    

  • disease risk
    
    

• Free-range
  
  

  • better ethically/environmentally
    
    

  • costs more
    
    

Forestry

• Clear cutting = worst
  
  

• Selective cutting = better
  
  

• Deforestation → erosion + climate change
  
  

Mining

• Surface mining destroys land
  
  

• Acid mine drainage pollutes water
  
  

Urbanization

• Habitat loss
  
  

• Heat Island Effect
  
  

• More runoff + flooding
  
  

Sustainability

• Ecological footprint: measures environmental impact
  
  

• Sustainable agriculture
  
  

• Conservation
  
  

• Reforestation
  
  

• Efficient water use