South America is home to some of the largest and richest ecosystems on Earth. From the dense Amazon rainforest to the flooded Pantanal wetlands, these ecosystems are vital for global climate balance, biodiversity conservation, and indigenous communities.

---

🌎 7.1 Amazon Rainforest

• Location: Brazil (60%), Peru, Colombia, Venezuela, Ecuador, Bolivia, Guyana, Suriname, French Guiana.
• Size: ~5.5 million sq. km → largest tropical rainforest in the world.
• River Basin: Amazon River system.
• Biodiversity:
  • 10% of world’s species.
  • Jaguars, anacondas, pink dolphins, toucans.
  • Rich plant life – many with medicinal value.
• Importance:
  • Called the “Lungs of the Earth” → produces ~20% of world’s oxygen.
  • Huge carbon sink → absorbs CO₂.
  • Home to hundreds of indigenous tribes.
• Threats:
  • Deforestation (logging, soy farming, cattle ranching).
  • Fires, climate change.

---

🌎 7.2 Atlantic Forest (Mata Atlântica)

• Location: Coastal Brazil (São Paulo, Rio de Janeiro).
• Size: Once covered 1.3 million sq. km → now reduced to <10% of original size.
• Biodiversity:
  • One of the world’s most endangered biodiversity hotspots.
  • Golden lion tamarin, endemic birds.
• Threats: Urbanization, agriculture, deforestation.

---

🌎 7.3 Valdivian Temperate Rainforest

• Location: Chile & Argentina (between Andes & Pacific).
• Climate: Temperate, high rainfall.
• Vegetation: Evergreen trees, ferns, mosses.
• Unique Species: Southern pudú (world’s smallest deer).
• Importance: Rare temperate rainforest biome in the Southern Hemisphere.

---

🌎 7.4 Pantanal Wetlands

• Location: Brazil (mostly), Bolivia, Paraguay.
• Size: ~195,000 sq. km → largest tropical wetland in the world.
• Biodiversity:
  • Jaguars, capybaras, giant otters, caimans, 650+ bird species.
• Importance:
  • Critical for water regulation & fisheries.
  • Key ecotourism region.
• Threats: Deforestation, water diversion, fires.

---

🌎 7.5 Other Forests & Wetlands

• Gran Chaco (Argentina, Paraguay, Bolivia): Dry forest-savanna mix, cattle ranching.
• Llanos Wetlands (Orinoco Basin): Flooded savanna, cattle grazing.
• Iguaçu Falls (Brazil–Argentina border): Surrounded by subtropical rainforest.

---

📌 UPSC Key Pointers

1. Amazon Rainforest → Largest tropical forest; carbon sink; “Lungs of the Earth.”
2. Atlantic Forest → Highly endangered, <10% left.
3. Valdivian Rainforest → Rare temperate rainforest in Southern Hemisphere.
4. Pantanal Wetlands → Largest tropical wetland; Ramsar significance.
5. Gran Chaco → Semi-arid dry forest, agriculture expansion.
6. Deforestation, El Niño, and climate change → major threats to ecosystems.